OpenCloudOS-Kernel/drivers/usb/early/ehci-dbgp.c

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USB: ehci-dbgp: stability improvements and external re-init This patch implements several changes: 1) Improve the capability to debug the dbgp driver The dbgp_ehci_status() was added in a number of places to report the critical ehci registers to diagnose the cause of a failure of the ehci-dbgp driver. 2) Capability to survive the host controller initialization The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were added so as to allow the ehci-dbgp to re-initialize after the ehci host controller is reset by the standard host controller driver. This same routine is common for the early startup or re-initialization. This resulted in the need to move some of the initialization code out of the __init section because the ehci driver has the possibility to be loaded later on as a kernel module. 3) Stability improvements for device initialization The device enumeration from 0 to 127 has the possibility to fail the first time after a warm reset on some older EHCI debug controllers. The enumeration will be tried up to 3 times to account for this failure case. The dbg_wait_until_complete() was changed to wait up to 250 ms before failing which only comes into play during device initialization. The maximum delay will never get hit during the course of normal operation of the driver, unless the device got unplugged or there was a ehci controller failure, in which case the dbgp device driver will shut itself down. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: dbrownell@users.sourceforge.net Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-21 04:39:53 +08:00
/*
* Standalone EHCI usb debug driver
*
* Originally written by:
* Eric W. Biederman" <ebiederm@xmission.com> and
* Yinghai Lu <yhlu.kernel@gmail.com>
*
* Changes for early/late printk and HW errata:
* Jason Wessel <jason.wessel@windriver.com>
* Copyright (C) 2009 Wind River Systems, Inc.
*
*/
#include <linux/console.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/pci_regs.h>
#include <linux/pci_ids.h>
#include <linux/usb/ch9.h>
#include <linux/usb/ehci_def.h>
#include <linux/delay.h>
echi-dbgp: Add kernel debugger support for the usb debug port This patch adds the capability to use the usb debug port with the kernel debugger. It is also still possible to use this functionality with or without the earlyprintk=dbgpX. It is possible to use the kgdbwait boot argument to debug very early in the kernel start up code. There are two ways to use this driver extension with a kernel boot argument. 1) kgdbdbgp=# -- Where # is the number of the usb debug controller You must use sysrq-g to break into the kernel debugger on another connection type other than the dbgp. 2) kgdbdbgp=#debugControlNum#,#Seconds# In this mode, the usb debug port is polled every #Seconds# for character input. It is possible to use gdb or press control-c to break into the kernel debugger. From the implementation perspective there are 3 high level changes. 1) Allow variable retries for the the hardware via dbgp_bulk_read(). The amount of retries for the dbgp_bulk_read() needed to be variable instead of fixed. We do not want to poll at all when the kernel is operating in interrupt driven mode. The polling only occurs if the kernel was booted when specifying some number of seconds via the kgdbdbgp boot argument (IE kgdbdbgp=0,1). In this case the loop count is reduced to 1 so as introduce the smallest amount of latency as possible. 2) Save the bulk IN endpoint address for use by the kgdb code. 3) The addition of the kgdb interface code. This consisted of adding in a character read function for the dbgp as well as a polling thread to allow the dbgp to interrupt the kernel execution. The rest is the typical kgdb I/O api. CC: Eric Biederman <ebiederm@xmission.com> CC: Yinghai Lu <yhlu.kernel@gmail.com> CC: linux-usb@vger.kernel.org Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21 10:04:31 +08:00
#include <linux/serial_core.h>
#include <linux/kgdb.h>
#include <linux/kthread.h>
#include <asm/io.h>
#include <asm/pci-direct.h>
#include <asm/fixmap.h>
USB: ehci-dbgp: stability improvements and external re-init This patch implements several changes: 1) Improve the capability to debug the dbgp driver The dbgp_ehci_status() was added in a number of places to report the critical ehci registers to diagnose the cause of a failure of the ehci-dbgp driver. 2) Capability to survive the host controller initialization The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were added so as to allow the ehci-dbgp to re-initialize after the ehci host controller is reset by the standard host controller driver. This same routine is common for the early startup or re-initialization. This resulted in the need to move some of the initialization code out of the __init section because the ehci driver has the possibility to be loaded later on as a kernel module. 3) Stability improvements for device initialization The device enumeration from 0 to 127 has the possibility to fail the first time after a warm reset on some older EHCI debug controllers. The enumeration will be tried up to 3 times to account for this failure case. The dbg_wait_until_complete() was changed to wait up to 250 ms before failing which only comes into play during device initialization. The maximum delay will never get hit during the course of normal operation of the driver, unless the device got unplugged or there was a ehci controller failure, in which case the dbgp device driver will shut itself down. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: dbrownell@users.sourceforge.net Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-21 04:39:53 +08:00
/* The code here is intended to talk directly to the EHCI debug port
* and does not require that you have any kind of USB host controller
* drivers or USB device drivers compiled into the kernel.
*
* If you make a change to anything in here, the following test cases
* need to pass where a USB debug device works in the following
* configurations.
*
* 1. boot args: earlyprintk=dbgp
* o kernel compiled with # CONFIG_USB_EHCI_HCD is not set
* o kernel compiled with CONFIG_USB_EHCI_HCD=y
* 2. boot args: earlyprintk=dbgp,keep
* o kernel compiled with # CONFIG_USB_EHCI_HCD is not set
* o kernel compiled with CONFIG_USB_EHCI_HCD=y
* 3. boot args: earlyprintk=dbgp console=ttyUSB0
* o kernel has CONFIG_USB_EHCI_HCD=y and
* CONFIG_USB_SERIAL_DEBUG=y
* 4. boot args: earlyprintk=vga,dbgp
* o kernel compiled with # CONFIG_USB_EHCI_HCD is not set
* o kernel compiled with CONFIG_USB_EHCI_HCD=y
*
* For the 4th configuration you can turn on or off the DBGP_DEBUG
* such that you can debug the dbgp device's driver code.
*/
static int dbgp_phys_port = 1;
static struct ehci_caps __iomem *ehci_caps;
static struct ehci_regs __iomem *ehci_regs;
static struct ehci_dbg_port __iomem *ehci_debug;
USB: ehci-dbgp: stability improvements and external re-init This patch implements several changes: 1) Improve the capability to debug the dbgp driver The dbgp_ehci_status() was added in a number of places to report the critical ehci registers to diagnose the cause of a failure of the ehci-dbgp driver. 2) Capability to survive the host controller initialization The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were added so as to allow the ehci-dbgp to re-initialize after the ehci host controller is reset by the standard host controller driver. This same routine is common for the early startup or re-initialization. This resulted in the need to move some of the initialization code out of the __init section because the ehci driver has the possibility to be loaded later on as a kernel module. 3) Stability improvements for device initialization The device enumeration from 0 to 127 has the possibility to fail the first time after a warm reset on some older EHCI debug controllers. The enumeration will be tried up to 3 times to account for this failure case. The dbg_wait_until_complete() was changed to wait up to 250 ms before failing which only comes into play during device initialization. The maximum delay will never get hit during the course of normal operation of the driver, unless the device got unplugged or there was a ehci controller failure, in which case the dbgp device driver will shut itself down. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: dbrownell@users.sourceforge.net Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-21 04:39:53 +08:00
static int dbgp_not_safe; /* Cannot use debug device during ehci reset */
static unsigned int dbgp_endpoint_out;
echi-dbgp: Add kernel debugger support for the usb debug port This patch adds the capability to use the usb debug port with the kernel debugger. It is also still possible to use this functionality with or without the earlyprintk=dbgpX. It is possible to use the kgdbwait boot argument to debug very early in the kernel start up code. There are two ways to use this driver extension with a kernel boot argument. 1) kgdbdbgp=# -- Where # is the number of the usb debug controller You must use sysrq-g to break into the kernel debugger on another connection type other than the dbgp. 2) kgdbdbgp=#debugControlNum#,#Seconds# In this mode, the usb debug port is polled every #Seconds# for character input. It is possible to use gdb or press control-c to break into the kernel debugger. From the implementation perspective there are 3 high level changes. 1) Allow variable retries for the the hardware via dbgp_bulk_read(). The amount of retries for the dbgp_bulk_read() needed to be variable instead of fixed. We do not want to poll at all when the kernel is operating in interrupt driven mode. The polling only occurs if the kernel was booted when specifying some number of seconds via the kgdbdbgp boot argument (IE kgdbdbgp=0,1). In this case the loop count is reduced to 1 so as introduce the smallest amount of latency as possible. 2) Save the bulk IN endpoint address for use by the kgdb code. 3) The addition of the kgdb interface code. This consisted of adding in a character read function for the dbgp as well as a polling thread to allow the dbgp to interrupt the kernel execution. The rest is the typical kgdb I/O api. CC: Eric Biederman <ebiederm@xmission.com> CC: Yinghai Lu <yhlu.kernel@gmail.com> CC: linux-usb@vger.kernel.org Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21 10:04:31 +08:00
static unsigned int dbgp_endpoint_in;
struct ehci_dev {
u32 bus;
u32 slot;
u32 func;
};
static struct ehci_dev ehci_dev;
#define USB_DEBUG_DEVNUM 127
USB: ehci-dbgp: stability improvements and external re-init This patch implements several changes: 1) Improve the capability to debug the dbgp driver The dbgp_ehci_status() was added in a number of places to report the critical ehci registers to diagnose the cause of a failure of the ehci-dbgp driver. 2) Capability to survive the host controller initialization The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were added so as to allow the ehci-dbgp to re-initialize after the ehci host controller is reset by the standard host controller driver. This same routine is common for the early startup or re-initialization. This resulted in the need to move some of the initialization code out of the __init section because the ehci driver has the possibility to be loaded later on as a kernel module. 3) Stability improvements for device initialization The device enumeration from 0 to 127 has the possibility to fail the first time after a warm reset on some older EHCI debug controllers. The enumeration will be tried up to 3 times to account for this failure case. The dbg_wait_until_complete() was changed to wait up to 250 ms before failing which only comes into play during device initialization. The maximum delay will never get hit during the course of normal operation of the driver, unless the device got unplugged or there was a ehci controller failure, in which case the dbgp device driver will shut itself down. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: dbrownell@users.sourceforge.net Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-21 04:39:53 +08:00
#ifdef DBGP_DEBUG
#define dbgp_printk printk
static void dbgp_ehci_status(char *str)
{
if (!ehci_debug)
return;
dbgp_printk("dbgp: %s\n", str);
dbgp_printk(" Debug control: %08x", readl(&ehci_debug->control));
dbgp_printk(" ehci cmd : %08x", readl(&ehci_regs->command));
dbgp_printk(" ehci conf flg: %08x\n",
readl(&ehci_regs->configured_flag));
dbgp_printk(" ehci status : %08x", readl(&ehci_regs->status));
dbgp_printk(" ehci portsc : %08x\n",
readl(&ehci_regs->port_status[dbgp_phys_port - 1]));
}
#else
static inline void dbgp_ehci_status(char *str) { }
static inline void dbgp_printk(const char *fmt, ...) { }
#endif
static inline u32 dbgp_len_update(u32 x, u32 len)
{
return (x & ~0x0f) | (len & 0x0f);
}
echi-dbgp: Add kernel debugger support for the usb debug port This patch adds the capability to use the usb debug port with the kernel debugger. It is also still possible to use this functionality with or without the earlyprintk=dbgpX. It is possible to use the kgdbwait boot argument to debug very early in the kernel start up code. There are two ways to use this driver extension with a kernel boot argument. 1) kgdbdbgp=# -- Where # is the number of the usb debug controller You must use sysrq-g to break into the kernel debugger on another connection type other than the dbgp. 2) kgdbdbgp=#debugControlNum#,#Seconds# In this mode, the usb debug port is polled every #Seconds# for character input. It is possible to use gdb or press control-c to break into the kernel debugger. From the implementation perspective there are 3 high level changes. 1) Allow variable retries for the the hardware via dbgp_bulk_read(). The amount of retries for the dbgp_bulk_read() needed to be variable instead of fixed. We do not want to poll at all when the kernel is operating in interrupt driven mode. The polling only occurs if the kernel was booted when specifying some number of seconds via the kgdbdbgp boot argument (IE kgdbdbgp=0,1). In this case the loop count is reduced to 1 so as introduce the smallest amount of latency as possible. 2) Save the bulk IN endpoint address for use by the kgdb code. 3) The addition of the kgdb interface code. This consisted of adding in a character read function for the dbgp as well as a polling thread to allow the dbgp to interrupt the kernel execution. The rest is the typical kgdb I/O api. CC: Eric Biederman <ebiederm@xmission.com> CC: Yinghai Lu <yhlu.kernel@gmail.com> CC: linux-usb@vger.kernel.org Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21 10:04:31 +08:00
#ifdef CONFIG_KGDB
static struct kgdb_io kgdbdbgp_io_ops;
#define dbgp_kgdb_mode (dbg_io_ops == &kgdbdbgp_io_ops)
#else
#define dbgp_kgdb_mode (0)
#endif
/* Local version of HC_LENGTH macro as ehci struct is not available here */
#define EARLY_HC_LENGTH(p) (0x00ff & (p)) /* bits 7 : 0 */
/*
* USB Packet IDs (PIDs)
*/
/* token */
#define USB_PID_OUT 0xe1
#define USB_PID_IN 0x69
#define USB_PID_SOF 0xa5
#define USB_PID_SETUP 0x2d
/* handshake */
#define USB_PID_ACK 0xd2
#define USB_PID_NAK 0x5a
#define USB_PID_STALL 0x1e
#define USB_PID_NYET 0x96
/* data */
#define USB_PID_DATA0 0xc3
#define USB_PID_DATA1 0x4b
#define USB_PID_DATA2 0x87
#define USB_PID_MDATA 0x0f
/* Special */
#define USB_PID_PREAMBLE 0x3c
#define USB_PID_ERR 0x3c
#define USB_PID_SPLIT 0x78
#define USB_PID_PING 0xb4
#define USB_PID_UNDEF_0 0xf0
#define USB_PID_DATA_TOGGLE 0x88
#define DBGP_CLAIM (DBGP_OWNER | DBGP_ENABLED | DBGP_INUSE)
#define PCI_CAP_ID_EHCI_DEBUG 0xa
#define HUB_ROOT_RESET_TIME 50 /* times are in msec */
#define HUB_SHORT_RESET_TIME 10
#define HUB_LONG_RESET_TIME 200
#define HUB_RESET_TIMEOUT 500
#define DBGP_MAX_PACKET 8
USB: ehci-dbgp: stability improvements and external re-init This patch implements several changes: 1) Improve the capability to debug the dbgp driver The dbgp_ehci_status() was added in a number of places to report the critical ehci registers to diagnose the cause of a failure of the ehci-dbgp driver. 2) Capability to survive the host controller initialization The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were added so as to allow the ehci-dbgp to re-initialize after the ehci host controller is reset by the standard host controller driver. This same routine is common for the early startup or re-initialization. This resulted in the need to move some of the initialization code out of the __init section because the ehci driver has the possibility to be loaded later on as a kernel module. 3) Stability improvements for device initialization The device enumeration from 0 to 127 has the possibility to fail the first time after a warm reset on some older EHCI debug controllers. The enumeration will be tried up to 3 times to account for this failure case. The dbg_wait_until_complete() was changed to wait up to 250 ms before failing which only comes into play during device initialization. The maximum delay will never get hit during the course of normal operation of the driver, unless the device got unplugged or there was a ehci controller failure, in which case the dbgp device driver will shut itself down. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: dbrownell@users.sourceforge.net Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-21 04:39:53 +08:00
#define DBGP_TIMEOUT (250 * 1000)
#define DBGP_LOOPS 1000
static inline u32 dbgp_pid_write_update(u32 x, u32 tok)
{
static int data0 = USB_PID_DATA1;
data0 ^= USB_PID_DATA_TOGGLE;
return (x & 0xffff0000) | (data0 << 8) | (tok & 0xff);
}
static inline u32 dbgp_pid_read_update(u32 x, u32 tok)
{
return (x & 0xffff0000) | (USB_PID_DATA0 << 8) | (tok & 0xff);
}
static int dbgp_wait_until_complete(void)
{
u32 ctrl;
USB: ehci-dbgp: stability improvements and external re-init This patch implements several changes: 1) Improve the capability to debug the dbgp driver The dbgp_ehci_status() was added in a number of places to report the critical ehci registers to diagnose the cause of a failure of the ehci-dbgp driver. 2) Capability to survive the host controller initialization The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were added so as to allow the ehci-dbgp to re-initialize after the ehci host controller is reset by the standard host controller driver. This same routine is common for the early startup or re-initialization. This resulted in the need to move some of the initialization code out of the __init section because the ehci driver has the possibility to be loaded later on as a kernel module. 3) Stability improvements for device initialization The device enumeration from 0 to 127 has the possibility to fail the first time after a warm reset on some older EHCI debug controllers. The enumeration will be tried up to 3 times to account for this failure case. The dbg_wait_until_complete() was changed to wait up to 250 ms before failing which only comes into play during device initialization. The maximum delay will never get hit during the course of normal operation of the driver, unless the device got unplugged or there was a ehci controller failure, in which case the dbgp device driver will shut itself down. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: dbrownell@users.sourceforge.net Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-21 04:39:53 +08:00
int loop = DBGP_TIMEOUT;
do {
ctrl = readl(&ehci_debug->control);
/* Stop when the transaction is finished */
if (ctrl & DBGP_DONE)
break;
USB: ehci-dbgp: stability improvements and external re-init This patch implements several changes: 1) Improve the capability to debug the dbgp driver The dbgp_ehci_status() was added in a number of places to report the critical ehci registers to diagnose the cause of a failure of the ehci-dbgp driver. 2) Capability to survive the host controller initialization The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were added so as to allow the ehci-dbgp to re-initialize after the ehci host controller is reset by the standard host controller driver. This same routine is common for the early startup or re-initialization. This resulted in the need to move some of the initialization code out of the __init section because the ehci driver has the possibility to be loaded later on as a kernel module. 3) Stability improvements for device initialization The device enumeration from 0 to 127 has the possibility to fail the first time after a warm reset on some older EHCI debug controllers. The enumeration will be tried up to 3 times to account for this failure case. The dbg_wait_until_complete() was changed to wait up to 250 ms before failing which only comes into play during device initialization. The maximum delay will never get hit during the course of normal operation of the driver, unless the device got unplugged or there was a ehci controller failure, in which case the dbgp device driver will shut itself down. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: dbrownell@users.sourceforge.net Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-21 04:39:53 +08:00
udelay(1);
} while (--loop > 0);
if (!loop)
USB: ehci-dbgp: stability improvements and external re-init This patch implements several changes: 1) Improve the capability to debug the dbgp driver The dbgp_ehci_status() was added in a number of places to report the critical ehci registers to diagnose the cause of a failure of the ehci-dbgp driver. 2) Capability to survive the host controller initialization The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were added so as to allow the ehci-dbgp to re-initialize after the ehci host controller is reset by the standard host controller driver. This same routine is common for the early startup or re-initialization. This resulted in the need to move some of the initialization code out of the __init section because the ehci driver has the possibility to be loaded later on as a kernel module. 3) Stability improvements for device initialization The device enumeration from 0 to 127 has the possibility to fail the first time after a warm reset on some older EHCI debug controllers. The enumeration will be tried up to 3 times to account for this failure case. The dbg_wait_until_complete() was changed to wait up to 250 ms before failing which only comes into play during device initialization. The maximum delay will never get hit during the course of normal operation of the driver, unless the device got unplugged or there was a ehci controller failure, in which case the dbgp device driver will shut itself down. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: dbrownell@users.sourceforge.net Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-21 04:39:53 +08:00
return -DBGP_TIMEOUT;
/*
* Now that we have observed the completed transaction,
* clear the done bit.
*/
writel(ctrl | DBGP_DONE, &ehci_debug->control);
return (ctrl & DBGP_ERROR) ? -DBGP_ERRCODE(ctrl) : DBGP_LEN(ctrl);
}
USB: ehci-dbgp: stability improvements and external re-init This patch implements several changes: 1) Improve the capability to debug the dbgp driver The dbgp_ehci_status() was added in a number of places to report the critical ehci registers to diagnose the cause of a failure of the ehci-dbgp driver. 2) Capability to survive the host controller initialization The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were added so as to allow the ehci-dbgp to re-initialize after the ehci host controller is reset by the standard host controller driver. This same routine is common for the early startup or re-initialization. This resulted in the need to move some of the initialization code out of the __init section because the ehci driver has the possibility to be loaded later on as a kernel module. 3) Stability improvements for device initialization The device enumeration from 0 to 127 has the possibility to fail the first time after a warm reset on some older EHCI debug controllers. The enumeration will be tried up to 3 times to account for this failure case. The dbg_wait_until_complete() was changed to wait up to 250 ms before failing which only comes into play during device initialization. The maximum delay will never get hit during the course of normal operation of the driver, unless the device got unplugged or there was a ehci controller failure, in which case the dbgp device driver will shut itself down. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: dbrownell@users.sourceforge.net Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-21 04:39:53 +08:00
static inline void dbgp_mdelay(int ms)
{
int i;
while (ms--) {
for (i = 0; i < 1000; i++)
outb(0x1, 0x80);
}
}
static void dbgp_breath(void)
{
/* Sleep to give the debug port a chance to breathe */
}
echi-dbgp: Add kernel debugger support for the usb debug port This patch adds the capability to use the usb debug port with the kernel debugger. It is also still possible to use this functionality with or without the earlyprintk=dbgpX. It is possible to use the kgdbwait boot argument to debug very early in the kernel start up code. There are two ways to use this driver extension with a kernel boot argument. 1) kgdbdbgp=# -- Where # is the number of the usb debug controller You must use sysrq-g to break into the kernel debugger on another connection type other than the dbgp. 2) kgdbdbgp=#debugControlNum#,#Seconds# In this mode, the usb debug port is polled every #Seconds# for character input. It is possible to use gdb or press control-c to break into the kernel debugger. From the implementation perspective there are 3 high level changes. 1) Allow variable retries for the the hardware via dbgp_bulk_read(). The amount of retries for the dbgp_bulk_read() needed to be variable instead of fixed. We do not want to poll at all when the kernel is operating in interrupt driven mode. The polling only occurs if the kernel was booted when specifying some number of seconds via the kgdbdbgp boot argument (IE kgdbdbgp=0,1). In this case the loop count is reduced to 1 so as introduce the smallest amount of latency as possible. 2) Save the bulk IN endpoint address for use by the kgdb code. 3) The addition of the kgdb interface code. This consisted of adding in a character read function for the dbgp as well as a polling thread to allow the dbgp to interrupt the kernel execution. The rest is the typical kgdb I/O api. CC: Eric Biederman <ebiederm@xmission.com> CC: Yinghai Lu <yhlu.kernel@gmail.com> CC: linux-usb@vger.kernel.org Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21 10:04:31 +08:00
static int dbgp_wait_until_done(unsigned ctrl, int loop)
{
u32 pids, lpid;
int ret;
retry:
writel(ctrl | DBGP_GO, &ehci_debug->control);
ret = dbgp_wait_until_complete();
pids = readl(&ehci_debug->pids);
lpid = DBGP_PID_GET(pids);
USB: ehci-dbgp: stability improvements and external re-init This patch implements several changes: 1) Improve the capability to debug the dbgp driver The dbgp_ehci_status() was added in a number of places to report the critical ehci registers to diagnose the cause of a failure of the ehci-dbgp driver. 2) Capability to survive the host controller initialization The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were added so as to allow the ehci-dbgp to re-initialize after the ehci host controller is reset by the standard host controller driver. This same routine is common for the early startup or re-initialization. This resulted in the need to move some of the initialization code out of the __init section because the ehci driver has the possibility to be loaded later on as a kernel module. 3) Stability improvements for device initialization The device enumeration from 0 to 127 has the possibility to fail the first time after a warm reset on some older EHCI debug controllers. The enumeration will be tried up to 3 times to account for this failure case. The dbg_wait_until_complete() was changed to wait up to 250 ms before failing which only comes into play during device initialization. The maximum delay will never get hit during the course of normal operation of the driver, unless the device got unplugged or there was a ehci controller failure, in which case the dbgp device driver will shut itself down. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: dbrownell@users.sourceforge.net Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-21 04:39:53 +08:00
if (ret < 0) {
/* A -DBGP_TIMEOUT failure here means the device has
* failed, perhaps because it was unplugged, in which
* case we do not want to hang the system so the dbgp
* will be marked as unsafe to use. EHCI reset is the
* only way to recover if you unplug the dbgp device.
*/
if (ret == -DBGP_TIMEOUT && !dbgp_not_safe)
dbgp_not_safe = 1;
if (ret == -DBGP_ERR_BAD && --loop > 0)
goto retry;
return ret;
USB: ehci-dbgp: stability improvements and external re-init This patch implements several changes: 1) Improve the capability to debug the dbgp driver The dbgp_ehci_status() was added in a number of places to report the critical ehci registers to diagnose the cause of a failure of the ehci-dbgp driver. 2) Capability to survive the host controller initialization The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were added so as to allow the ehci-dbgp to re-initialize after the ehci host controller is reset by the standard host controller driver. This same routine is common for the early startup or re-initialization. This resulted in the need to move some of the initialization code out of the __init section because the ehci driver has the possibility to be loaded later on as a kernel module. 3) Stability improvements for device initialization The device enumeration from 0 to 127 has the possibility to fail the first time after a warm reset on some older EHCI debug controllers. The enumeration will be tried up to 3 times to account for this failure case. The dbg_wait_until_complete() was changed to wait up to 250 ms before failing which only comes into play during device initialization. The maximum delay will never get hit during the course of normal operation of the driver, unless the device got unplugged or there was a ehci controller failure, in which case the dbgp device driver will shut itself down. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: dbrownell@users.sourceforge.net Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-21 04:39:53 +08:00
}
/*
* If the port is getting full or it has dropped data
* start pacing ourselves, not necessary but it's friendly.
*/
if ((lpid == USB_PID_NAK) || (lpid == USB_PID_NYET))
dbgp_breath();
/* If I get a NACK reissue the transmission */
if (lpid == USB_PID_NAK) {
if (--loop > 0)
goto retry;
}
return ret;
}
USB: ehci-dbgp: stability improvements and external re-init This patch implements several changes: 1) Improve the capability to debug the dbgp driver The dbgp_ehci_status() was added in a number of places to report the critical ehci registers to diagnose the cause of a failure of the ehci-dbgp driver. 2) Capability to survive the host controller initialization The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were added so as to allow the ehci-dbgp to re-initialize after the ehci host controller is reset by the standard host controller driver. This same routine is common for the early startup or re-initialization. This resulted in the need to move some of the initialization code out of the __init section because the ehci driver has the possibility to be loaded later on as a kernel module. 3) Stability improvements for device initialization The device enumeration from 0 to 127 has the possibility to fail the first time after a warm reset on some older EHCI debug controllers. The enumeration will be tried up to 3 times to account for this failure case. The dbg_wait_until_complete() was changed to wait up to 250 ms before failing which only comes into play during device initialization. The maximum delay will never get hit during the course of normal operation of the driver, unless the device got unplugged or there was a ehci controller failure, in which case the dbgp device driver will shut itself down. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: dbrownell@users.sourceforge.net Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-21 04:39:53 +08:00
static inline void dbgp_set_data(const void *buf, int size)
{
const unsigned char *bytes = buf;
u32 lo, hi;
int i;
lo = hi = 0;
for (i = 0; i < 4 && i < size; i++)
lo |= bytes[i] << (8*i);
for (; i < 8 && i < size; i++)
hi |= bytes[i] << (8*(i - 4));
writel(lo, &ehci_debug->data03);
writel(hi, &ehci_debug->data47);
}
USB: ehci-dbgp: stability improvements and external re-init This patch implements several changes: 1) Improve the capability to debug the dbgp driver The dbgp_ehci_status() was added in a number of places to report the critical ehci registers to diagnose the cause of a failure of the ehci-dbgp driver. 2) Capability to survive the host controller initialization The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were added so as to allow the ehci-dbgp to re-initialize after the ehci host controller is reset by the standard host controller driver. This same routine is common for the early startup or re-initialization. This resulted in the need to move some of the initialization code out of the __init section because the ehci driver has the possibility to be loaded later on as a kernel module. 3) Stability improvements for device initialization The device enumeration from 0 to 127 has the possibility to fail the first time after a warm reset on some older EHCI debug controllers. The enumeration will be tried up to 3 times to account for this failure case. The dbg_wait_until_complete() was changed to wait up to 250 ms before failing which only comes into play during device initialization. The maximum delay will never get hit during the course of normal operation of the driver, unless the device got unplugged or there was a ehci controller failure, in which case the dbgp device driver will shut itself down. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: dbrownell@users.sourceforge.net Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-21 04:39:53 +08:00
static inline void dbgp_get_data(void *buf, int size)
{
unsigned char *bytes = buf;
u32 lo, hi;
int i;
lo = readl(&ehci_debug->data03);
hi = readl(&ehci_debug->data47);
for (i = 0; i < 4 && i < size; i++)
bytes[i] = (lo >> (8*i)) & 0xff;
for (; i < 8 && i < size; i++)
bytes[i] = (hi >> (8*(i - 4))) & 0xff;
}
static int dbgp_bulk_write(unsigned devnum, unsigned endpoint,
const char *bytes, int size)
{
int ret;
u32 addr;
u32 pids, ctrl;
if (size > DBGP_MAX_PACKET)
return -1;
addr = DBGP_EPADDR(devnum, endpoint);
pids = readl(&ehci_debug->pids);
pids = dbgp_pid_write_update(pids, USB_PID_OUT);
ctrl = readl(&ehci_debug->control);
ctrl = dbgp_len_update(ctrl, size);
ctrl |= DBGP_OUT;
ctrl |= DBGP_GO;
dbgp_set_data(bytes, size);
writel(addr, &ehci_debug->address);
writel(pids, &ehci_debug->pids);
echi-dbgp: Add kernel debugger support for the usb debug port This patch adds the capability to use the usb debug port with the kernel debugger. It is also still possible to use this functionality with or without the earlyprintk=dbgpX. It is possible to use the kgdbwait boot argument to debug very early in the kernel start up code. There are two ways to use this driver extension with a kernel boot argument. 1) kgdbdbgp=# -- Where # is the number of the usb debug controller You must use sysrq-g to break into the kernel debugger on another connection type other than the dbgp. 2) kgdbdbgp=#debugControlNum#,#Seconds# In this mode, the usb debug port is polled every #Seconds# for character input. It is possible to use gdb or press control-c to break into the kernel debugger. From the implementation perspective there are 3 high level changes. 1) Allow variable retries for the the hardware via dbgp_bulk_read(). The amount of retries for the dbgp_bulk_read() needed to be variable instead of fixed. We do not want to poll at all when the kernel is operating in interrupt driven mode. The polling only occurs if the kernel was booted when specifying some number of seconds via the kgdbdbgp boot argument (IE kgdbdbgp=0,1). In this case the loop count is reduced to 1 so as introduce the smallest amount of latency as possible. 2) Save the bulk IN endpoint address for use by the kgdb code. 3) The addition of the kgdb interface code. This consisted of adding in a character read function for the dbgp as well as a polling thread to allow the dbgp to interrupt the kernel execution. The rest is the typical kgdb I/O api. CC: Eric Biederman <ebiederm@xmission.com> CC: Yinghai Lu <yhlu.kernel@gmail.com> CC: linux-usb@vger.kernel.org Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21 10:04:31 +08:00
ret = dbgp_wait_until_done(ctrl, DBGP_LOOPS);
return ret;
}
USB: ehci-dbgp: stability improvements and external re-init This patch implements several changes: 1) Improve the capability to debug the dbgp driver The dbgp_ehci_status() was added in a number of places to report the critical ehci registers to diagnose the cause of a failure of the ehci-dbgp driver. 2) Capability to survive the host controller initialization The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were added so as to allow the ehci-dbgp to re-initialize after the ehci host controller is reset by the standard host controller driver. This same routine is common for the early startup or re-initialization. This resulted in the need to move some of the initialization code out of the __init section because the ehci driver has the possibility to be loaded later on as a kernel module. 3) Stability improvements for device initialization The device enumeration from 0 to 127 has the possibility to fail the first time after a warm reset on some older EHCI debug controllers. The enumeration will be tried up to 3 times to account for this failure case. The dbg_wait_until_complete() was changed to wait up to 250 ms before failing which only comes into play during device initialization. The maximum delay will never get hit during the course of normal operation of the driver, unless the device got unplugged or there was a ehci controller failure, in which case the dbgp device driver will shut itself down. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: dbrownell@users.sourceforge.net Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-21 04:39:53 +08:00
static int dbgp_bulk_read(unsigned devnum, unsigned endpoint, void *data,
echi-dbgp: Add kernel debugger support for the usb debug port This patch adds the capability to use the usb debug port with the kernel debugger. It is also still possible to use this functionality with or without the earlyprintk=dbgpX. It is possible to use the kgdbwait boot argument to debug very early in the kernel start up code. There are two ways to use this driver extension with a kernel boot argument. 1) kgdbdbgp=# -- Where # is the number of the usb debug controller You must use sysrq-g to break into the kernel debugger on another connection type other than the dbgp. 2) kgdbdbgp=#debugControlNum#,#Seconds# In this mode, the usb debug port is polled every #Seconds# for character input. It is possible to use gdb or press control-c to break into the kernel debugger. From the implementation perspective there are 3 high level changes. 1) Allow variable retries for the the hardware via dbgp_bulk_read(). The amount of retries for the dbgp_bulk_read() needed to be variable instead of fixed. We do not want to poll at all when the kernel is operating in interrupt driven mode. The polling only occurs if the kernel was booted when specifying some number of seconds via the kgdbdbgp boot argument (IE kgdbdbgp=0,1). In this case the loop count is reduced to 1 so as introduce the smallest amount of latency as possible. 2) Save the bulk IN endpoint address for use by the kgdb code. 3) The addition of the kgdb interface code. This consisted of adding in a character read function for the dbgp as well as a polling thread to allow the dbgp to interrupt the kernel execution. The rest is the typical kgdb I/O api. CC: Eric Biederman <ebiederm@xmission.com> CC: Yinghai Lu <yhlu.kernel@gmail.com> CC: linux-usb@vger.kernel.org Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21 10:04:31 +08:00
int size, int loops)
{
u32 pids, addr, ctrl;
int ret;
if (size > DBGP_MAX_PACKET)
return -1;
addr = DBGP_EPADDR(devnum, endpoint);
pids = readl(&ehci_debug->pids);
pids = dbgp_pid_read_update(pids, USB_PID_IN);
ctrl = readl(&ehci_debug->control);
ctrl = dbgp_len_update(ctrl, size);
ctrl &= ~DBGP_OUT;
ctrl |= DBGP_GO;
writel(addr, &ehci_debug->address);
writel(pids, &ehci_debug->pids);
echi-dbgp: Add kernel debugger support for the usb debug port This patch adds the capability to use the usb debug port with the kernel debugger. It is also still possible to use this functionality with or without the earlyprintk=dbgpX. It is possible to use the kgdbwait boot argument to debug very early in the kernel start up code. There are two ways to use this driver extension with a kernel boot argument. 1) kgdbdbgp=# -- Where # is the number of the usb debug controller You must use sysrq-g to break into the kernel debugger on another connection type other than the dbgp. 2) kgdbdbgp=#debugControlNum#,#Seconds# In this mode, the usb debug port is polled every #Seconds# for character input. It is possible to use gdb or press control-c to break into the kernel debugger. From the implementation perspective there are 3 high level changes. 1) Allow variable retries for the the hardware via dbgp_bulk_read(). The amount of retries for the dbgp_bulk_read() needed to be variable instead of fixed. We do not want to poll at all when the kernel is operating in interrupt driven mode. The polling only occurs if the kernel was booted when specifying some number of seconds via the kgdbdbgp boot argument (IE kgdbdbgp=0,1). In this case the loop count is reduced to 1 so as introduce the smallest amount of latency as possible. 2) Save the bulk IN endpoint address for use by the kgdb code. 3) The addition of the kgdb interface code. This consisted of adding in a character read function for the dbgp as well as a polling thread to allow the dbgp to interrupt the kernel execution. The rest is the typical kgdb I/O api. CC: Eric Biederman <ebiederm@xmission.com> CC: Yinghai Lu <yhlu.kernel@gmail.com> CC: linux-usb@vger.kernel.org Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21 10:04:31 +08:00
ret = dbgp_wait_until_done(ctrl, loops);
if (ret < 0)
return ret;
if (size > ret)
size = ret;
dbgp_get_data(data, size);
return ret;
}
USB: ehci-dbgp: stability improvements and external re-init This patch implements several changes: 1) Improve the capability to debug the dbgp driver The dbgp_ehci_status() was added in a number of places to report the critical ehci registers to diagnose the cause of a failure of the ehci-dbgp driver. 2) Capability to survive the host controller initialization The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were added so as to allow the ehci-dbgp to re-initialize after the ehci host controller is reset by the standard host controller driver. This same routine is common for the early startup or re-initialization. This resulted in the need to move some of the initialization code out of the __init section because the ehci driver has the possibility to be loaded later on as a kernel module. 3) Stability improvements for device initialization The device enumeration from 0 to 127 has the possibility to fail the first time after a warm reset on some older EHCI debug controllers. The enumeration will be tried up to 3 times to account for this failure case. The dbg_wait_until_complete() was changed to wait up to 250 ms before failing which only comes into play during device initialization. The maximum delay will never get hit during the course of normal operation of the driver, unless the device got unplugged or there was a ehci controller failure, in which case the dbgp device driver will shut itself down. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: dbrownell@users.sourceforge.net Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-21 04:39:53 +08:00
static int dbgp_control_msg(unsigned devnum, int requesttype,
int request, int value, int index, void *data, int size)
{
u32 pids, addr, ctrl;
struct usb_ctrlrequest req;
int read;
int ret;
read = (requesttype & USB_DIR_IN) != 0;
if (size > (read ? DBGP_MAX_PACKET : 0))
return -1;
/* Compute the control message */
req.bRequestType = requesttype;
req.bRequest = request;
req.wValue = cpu_to_le16(value);
req.wIndex = cpu_to_le16(index);
req.wLength = cpu_to_le16(size);
pids = DBGP_PID_SET(USB_PID_DATA0, USB_PID_SETUP);
addr = DBGP_EPADDR(devnum, 0);
ctrl = readl(&ehci_debug->control);
ctrl = dbgp_len_update(ctrl, sizeof(req));
ctrl |= DBGP_OUT;
ctrl |= DBGP_GO;
/* Send the setup message */
dbgp_set_data(&req, sizeof(req));
writel(addr, &ehci_debug->address);
writel(pids, &ehci_debug->pids);
echi-dbgp: Add kernel debugger support for the usb debug port This patch adds the capability to use the usb debug port with the kernel debugger. It is also still possible to use this functionality with or without the earlyprintk=dbgpX. It is possible to use the kgdbwait boot argument to debug very early in the kernel start up code. There are two ways to use this driver extension with a kernel boot argument. 1) kgdbdbgp=# -- Where # is the number of the usb debug controller You must use sysrq-g to break into the kernel debugger on another connection type other than the dbgp. 2) kgdbdbgp=#debugControlNum#,#Seconds# In this mode, the usb debug port is polled every #Seconds# for character input. It is possible to use gdb or press control-c to break into the kernel debugger. From the implementation perspective there are 3 high level changes. 1) Allow variable retries for the the hardware via dbgp_bulk_read(). The amount of retries for the dbgp_bulk_read() needed to be variable instead of fixed. We do not want to poll at all when the kernel is operating in interrupt driven mode. The polling only occurs if the kernel was booted when specifying some number of seconds via the kgdbdbgp boot argument (IE kgdbdbgp=0,1). In this case the loop count is reduced to 1 so as introduce the smallest amount of latency as possible. 2) Save the bulk IN endpoint address for use by the kgdb code. 3) The addition of the kgdb interface code. This consisted of adding in a character read function for the dbgp as well as a polling thread to allow the dbgp to interrupt the kernel execution. The rest is the typical kgdb I/O api. CC: Eric Biederman <ebiederm@xmission.com> CC: Yinghai Lu <yhlu.kernel@gmail.com> CC: linux-usb@vger.kernel.org Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21 10:04:31 +08:00
ret = dbgp_wait_until_done(ctrl, DBGP_LOOPS);
if (ret < 0)
return ret;
/* Read the result */
echi-dbgp: Add kernel debugger support for the usb debug port This patch adds the capability to use the usb debug port with the kernel debugger. It is also still possible to use this functionality with or without the earlyprintk=dbgpX. It is possible to use the kgdbwait boot argument to debug very early in the kernel start up code. There are two ways to use this driver extension with a kernel boot argument. 1) kgdbdbgp=# -- Where # is the number of the usb debug controller You must use sysrq-g to break into the kernel debugger on another connection type other than the dbgp. 2) kgdbdbgp=#debugControlNum#,#Seconds# In this mode, the usb debug port is polled every #Seconds# for character input. It is possible to use gdb or press control-c to break into the kernel debugger. From the implementation perspective there are 3 high level changes. 1) Allow variable retries for the the hardware via dbgp_bulk_read(). The amount of retries for the dbgp_bulk_read() needed to be variable instead of fixed. We do not want to poll at all when the kernel is operating in interrupt driven mode. The polling only occurs if the kernel was booted when specifying some number of seconds via the kgdbdbgp boot argument (IE kgdbdbgp=0,1). In this case the loop count is reduced to 1 so as introduce the smallest amount of latency as possible. 2) Save the bulk IN endpoint address for use by the kgdb code. 3) The addition of the kgdb interface code. This consisted of adding in a character read function for the dbgp as well as a polling thread to allow the dbgp to interrupt the kernel execution. The rest is the typical kgdb I/O api. CC: Eric Biederman <ebiederm@xmission.com> CC: Yinghai Lu <yhlu.kernel@gmail.com> CC: linux-usb@vger.kernel.org Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21 10:04:31 +08:00
return dbgp_bulk_read(devnum, 0, data, size, DBGP_LOOPS);
}
/* Find a PCI capability */
static u32 __init find_cap(u32 num, u32 slot, u32 func, int cap)
{
u8 pos;
int bytes;
if (!(read_pci_config_16(num, slot, func, PCI_STATUS) &
PCI_STATUS_CAP_LIST))
return 0;
pos = read_pci_config_byte(num, slot, func, PCI_CAPABILITY_LIST);
for (bytes = 0; bytes < 48 && pos >= 0x40; bytes++) {
u8 id;
pos &= ~3;
id = read_pci_config_byte(num, slot, func, pos+PCI_CAP_LIST_ID);
if (id == 0xff)
break;
if (id == cap)
return pos;
pos = read_pci_config_byte(num, slot, func,
pos+PCI_CAP_LIST_NEXT);
}
return 0;
}
static u32 __init __find_dbgp(u32 bus, u32 slot, u32 func)
{
u32 class;
class = read_pci_config(bus, slot, func, PCI_CLASS_REVISION);
if ((class >> 8) != PCI_CLASS_SERIAL_USB_EHCI)
return 0;
return find_cap(bus, slot, func, PCI_CAP_ID_EHCI_DEBUG);
}
static u32 __init find_dbgp(int ehci_num, u32 *rbus, u32 *rslot, u32 *rfunc)
{
u32 bus, slot, func;
for (bus = 0; bus < 256; bus++) {
for (slot = 0; slot < 32; slot++) {
for (func = 0; func < 8; func++) {
unsigned cap;
cap = __find_dbgp(bus, slot, func);
if (!cap)
continue;
if (ehci_num-- != 0)
continue;
*rbus = bus;
*rslot = slot;
*rfunc = func;
return cap;
}
}
}
return 0;
}
USB: ehci-dbgp: stability improvements and external re-init This patch implements several changes: 1) Improve the capability to debug the dbgp driver The dbgp_ehci_status() was added in a number of places to report the critical ehci registers to diagnose the cause of a failure of the ehci-dbgp driver. 2) Capability to survive the host controller initialization The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were added so as to allow the ehci-dbgp to re-initialize after the ehci host controller is reset by the standard host controller driver. This same routine is common for the early startup or re-initialization. This resulted in the need to move some of the initialization code out of the __init section because the ehci driver has the possibility to be loaded later on as a kernel module. 3) Stability improvements for device initialization The device enumeration from 0 to 127 has the possibility to fail the first time after a warm reset on some older EHCI debug controllers. The enumeration will be tried up to 3 times to account for this failure case. The dbg_wait_until_complete() was changed to wait up to 250 ms before failing which only comes into play during device initialization. The maximum delay will never get hit during the course of normal operation of the driver, unless the device got unplugged or there was a ehci controller failure, in which case the dbgp device driver will shut itself down. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: dbrownell@users.sourceforge.net Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-21 04:39:53 +08:00
static int dbgp_ehci_startup(void)
{
u32 ctrl, cmd, status;
int loop;
/* Claim ownership, but do not enable yet */
ctrl = readl(&ehci_debug->control);
ctrl |= DBGP_OWNER;
ctrl &= ~(DBGP_ENABLED | DBGP_INUSE);
writel(ctrl, &ehci_debug->control);
udelay(1);
dbgp_ehci_status("EHCI startup");
/* Start the ehci running */
cmd = readl(&ehci_regs->command);
cmd &= ~(CMD_LRESET | CMD_IAAD | CMD_PSE | CMD_ASE | CMD_RESET);
cmd |= CMD_RUN;
writel(cmd, &ehci_regs->command);
/* Ensure everything is routed to the EHCI */
writel(FLAG_CF, &ehci_regs->configured_flag);
/* Wait until the controller is no longer halted */
loop = 1000;
USB: ehci-dbgp: stability improvements and external re-init This patch implements several changes: 1) Improve the capability to debug the dbgp driver The dbgp_ehci_status() was added in a number of places to report the critical ehci registers to diagnose the cause of a failure of the ehci-dbgp driver. 2) Capability to survive the host controller initialization The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were added so as to allow the ehci-dbgp to re-initialize after the ehci host controller is reset by the standard host controller driver. This same routine is common for the early startup or re-initialization. This resulted in the need to move some of the initialization code out of the __init section because the ehci driver has the possibility to be loaded later on as a kernel module. 3) Stability improvements for device initialization The device enumeration from 0 to 127 has the possibility to fail the first time after a warm reset on some older EHCI debug controllers. The enumeration will be tried up to 3 times to account for this failure case. The dbg_wait_until_complete() was changed to wait up to 250 ms before failing which only comes into play during device initialization. The maximum delay will never get hit during the course of normal operation of the driver, unless the device got unplugged or there was a ehci controller failure, in which case the dbgp device driver will shut itself down. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: dbrownell@users.sourceforge.net Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-21 04:39:53 +08:00
do {
status = readl(&ehci_regs->status);
if (!(status & STS_HALT))
break;
udelay(1);
} while (--loop > 0);
if (!loop) {
dbgp_printk("ehci can not be started\n");
return -ENODEV;
}
dbgp_printk("ehci started\n");
return 0;
}
static int dbgp_ehci_controller_reset(void)
{
int loop = 250 * 1000;
u32 cmd;
/* Reset the EHCI controller */
cmd = readl(&ehci_regs->command);
cmd |= CMD_RESET;
writel(cmd, &ehci_regs->command);
do {
cmd = readl(&ehci_regs->command);
} while ((cmd & CMD_RESET) && (--loop > 0));
if (!loop) {
dbgp_printk("can not reset ehci\n");
return -1;
}
dbgp_ehci_status("ehci reset done");
return 0;
}
static int ehci_wait_for_port(int port);
/* Return 0 on success
* Return -ENODEV for any general failure
* Return -EIO if wait for port fails
*/
static int _dbgp_external_startup(void)
USB: ehci-dbgp: stability improvements and external re-init This patch implements several changes: 1) Improve the capability to debug the dbgp driver The dbgp_ehci_status() was added in a number of places to report the critical ehci registers to diagnose the cause of a failure of the ehci-dbgp driver. 2) Capability to survive the host controller initialization The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were added so as to allow the ehci-dbgp to re-initialize after the ehci host controller is reset by the standard host controller driver. This same routine is common for the early startup or re-initialization. This resulted in the need to move some of the initialization code out of the __init section because the ehci driver has the possibility to be loaded later on as a kernel module. 3) Stability improvements for device initialization The device enumeration from 0 to 127 has the possibility to fail the first time after a warm reset on some older EHCI debug controllers. The enumeration will be tried up to 3 times to account for this failure case. The dbg_wait_until_complete() was changed to wait up to 250 ms before failing which only comes into play during device initialization. The maximum delay will never get hit during the course of normal operation of the driver, unless the device got unplugged or there was a ehci controller failure, in which case the dbgp device driver will shut itself down. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: dbrownell@users.sourceforge.net Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-21 04:39:53 +08:00
{
int devnum;
struct usb_debug_descriptor dbgp_desc;
int ret;
u32 ctrl, portsc, cmd;
USB: ehci-dbgp: stability improvements and external re-init This patch implements several changes: 1) Improve the capability to debug the dbgp driver The dbgp_ehci_status() was added in a number of places to report the critical ehci registers to diagnose the cause of a failure of the ehci-dbgp driver. 2) Capability to survive the host controller initialization The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were added so as to allow the ehci-dbgp to re-initialize after the ehci host controller is reset by the standard host controller driver. This same routine is common for the early startup or re-initialization. This resulted in the need to move some of the initialization code out of the __init section because the ehci driver has the possibility to be loaded later on as a kernel module. 3) Stability improvements for device initialization The device enumeration from 0 to 127 has the possibility to fail the first time after a warm reset on some older EHCI debug controllers. The enumeration will be tried up to 3 times to account for this failure case. The dbg_wait_until_complete() was changed to wait up to 250 ms before failing which only comes into play during device initialization. The maximum delay will never get hit during the course of normal operation of the driver, unless the device got unplugged or there was a ehci controller failure, in which case the dbgp device driver will shut itself down. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: dbrownell@users.sourceforge.net Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-21 04:39:53 +08:00
int dbg_port = dbgp_phys_port;
int tries = 3;
int reset_port_tries = 1;
int try_hard_once = 1;
USB: ehci-dbgp: stability improvements and external re-init This patch implements several changes: 1) Improve the capability to debug the dbgp driver The dbgp_ehci_status() was added in a number of places to report the critical ehci registers to diagnose the cause of a failure of the ehci-dbgp driver. 2) Capability to survive the host controller initialization The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were added so as to allow the ehci-dbgp to re-initialize after the ehci host controller is reset by the standard host controller driver. This same routine is common for the early startup or re-initialization. This resulted in the need to move some of the initialization code out of the __init section because the ehci driver has the possibility to be loaded later on as a kernel module. 3) Stability improvements for device initialization The device enumeration from 0 to 127 has the possibility to fail the first time after a warm reset on some older EHCI debug controllers. The enumeration will be tried up to 3 times to account for this failure case. The dbg_wait_until_complete() was changed to wait up to 250 ms before failing which only comes into play during device initialization. The maximum delay will never get hit during the course of normal operation of the driver, unless the device got unplugged or there was a ehci controller failure, in which case the dbgp device driver will shut itself down. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: dbrownell@users.sourceforge.net Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-21 04:39:53 +08:00
try_port_reset_again:
USB: ehci-dbgp: stability improvements and external re-init This patch implements several changes: 1) Improve the capability to debug the dbgp driver The dbgp_ehci_status() was added in a number of places to report the critical ehci registers to diagnose the cause of a failure of the ehci-dbgp driver. 2) Capability to survive the host controller initialization The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were added so as to allow the ehci-dbgp to re-initialize after the ehci host controller is reset by the standard host controller driver. This same routine is common for the early startup or re-initialization. This resulted in the need to move some of the initialization code out of the __init section because the ehci driver has the possibility to be loaded later on as a kernel module. 3) Stability improvements for device initialization The device enumeration from 0 to 127 has the possibility to fail the first time after a warm reset on some older EHCI debug controllers. The enumeration will be tried up to 3 times to account for this failure case. The dbg_wait_until_complete() was changed to wait up to 250 ms before failing which only comes into play during device initialization. The maximum delay will never get hit during the course of normal operation of the driver, unless the device got unplugged or there was a ehci controller failure, in which case the dbgp device driver will shut itself down. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: dbrownell@users.sourceforge.net Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-21 04:39:53 +08:00
ret = dbgp_ehci_startup();
if (ret)
return ret;
/* Wait for a device to show up in the debug port */
ret = ehci_wait_for_port(dbg_port);
if (ret < 0) {
portsc = readl(&ehci_regs->port_status[dbg_port - 1]);
if (!(portsc & PORT_CONNECT) && try_hard_once) {
/* Last ditch effort to try to force enable
* the debug device by using the packet test
* ehci command to try and wake it up. */
try_hard_once = 0;
cmd = readl(&ehci_regs->command);
cmd &= ~CMD_RUN;
writel(cmd, &ehci_regs->command);
portsc = readl(&ehci_regs->port_status[dbg_port - 1]);
portsc |= PORT_TEST_PKT;
writel(portsc, &ehci_regs->port_status[dbg_port - 1]);
dbgp_ehci_status("Trying to force debug port online");
mdelay(50);
dbgp_ehci_controller_reset();
goto try_port_reset_again;
} else if (reset_port_tries--) {
goto try_port_reset_again;
}
USB: ehci-dbgp: stability improvements and external re-init This patch implements several changes: 1) Improve the capability to debug the dbgp driver The dbgp_ehci_status() was added in a number of places to report the critical ehci registers to diagnose the cause of a failure of the ehci-dbgp driver. 2) Capability to survive the host controller initialization The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were added so as to allow the ehci-dbgp to re-initialize after the ehci host controller is reset by the standard host controller driver. This same routine is common for the early startup or re-initialization. This resulted in the need to move some of the initialization code out of the __init section because the ehci driver has the possibility to be loaded later on as a kernel module. 3) Stability improvements for device initialization The device enumeration from 0 to 127 has the possibility to fail the first time after a warm reset on some older EHCI debug controllers. The enumeration will be tried up to 3 times to account for this failure case. The dbg_wait_until_complete() was changed to wait up to 250 ms before failing which only comes into play during device initialization. The maximum delay will never get hit during the course of normal operation of the driver, unless the device got unplugged or there was a ehci controller failure, in which case the dbgp device driver will shut itself down. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: dbrownell@users.sourceforge.net Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-21 04:39:53 +08:00
dbgp_printk("No device found in debug port\n");
return -EIO;
}
dbgp_ehci_status("wait for port done");
/* Enable the debug port */
ctrl = readl(&ehci_debug->control);
ctrl |= DBGP_CLAIM;
writel(ctrl, &ehci_debug->control);
ctrl = readl(&ehci_debug->control);
if ((ctrl & DBGP_CLAIM) != DBGP_CLAIM) {
dbgp_printk("No device in debug port\n");
writel(ctrl & ~DBGP_CLAIM, &ehci_debug->control);
return -ENODEV;
}
dbgp_ehci_status("debug ported enabled");
/* Completely transfer the debug device to the debug controller */
portsc = readl(&ehci_regs->port_status[dbg_port - 1]);
portsc &= ~PORT_PE;
writel(portsc, &ehci_regs->port_status[dbg_port - 1]);
dbgp_mdelay(100);
try_again:
/* Find the debug device and make it device number 127 */
for (devnum = 0; devnum <= 127; devnum++) {
ret = dbgp_control_msg(devnum,
USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
USB_REQ_GET_DESCRIPTOR, (USB_DT_DEBUG << 8), 0,
&dbgp_desc, sizeof(dbgp_desc));
if (ret > 0)
break;
}
if (devnum > 127) {
dbgp_printk("Could not find attached debug device\n");
goto err;
}
dbgp_endpoint_out = dbgp_desc.bDebugOutEndpoint;
echi-dbgp: Add kernel debugger support for the usb debug port This patch adds the capability to use the usb debug port with the kernel debugger. It is also still possible to use this functionality with or without the earlyprintk=dbgpX. It is possible to use the kgdbwait boot argument to debug very early in the kernel start up code. There are two ways to use this driver extension with a kernel boot argument. 1) kgdbdbgp=# -- Where # is the number of the usb debug controller You must use sysrq-g to break into the kernel debugger on another connection type other than the dbgp. 2) kgdbdbgp=#debugControlNum#,#Seconds# In this mode, the usb debug port is polled every #Seconds# for character input. It is possible to use gdb or press control-c to break into the kernel debugger. From the implementation perspective there are 3 high level changes. 1) Allow variable retries for the the hardware via dbgp_bulk_read(). The amount of retries for the dbgp_bulk_read() needed to be variable instead of fixed. We do not want to poll at all when the kernel is operating in interrupt driven mode. The polling only occurs if the kernel was booted when specifying some number of seconds via the kgdbdbgp boot argument (IE kgdbdbgp=0,1). In this case the loop count is reduced to 1 so as introduce the smallest amount of latency as possible. 2) Save the bulk IN endpoint address for use by the kgdb code. 3) The addition of the kgdb interface code. This consisted of adding in a character read function for the dbgp as well as a polling thread to allow the dbgp to interrupt the kernel execution. The rest is the typical kgdb I/O api. CC: Eric Biederman <ebiederm@xmission.com> CC: Yinghai Lu <yhlu.kernel@gmail.com> CC: linux-usb@vger.kernel.org Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21 10:04:31 +08:00
dbgp_endpoint_in = dbgp_desc.bDebugInEndpoint;
USB: ehci-dbgp: stability improvements and external re-init This patch implements several changes: 1) Improve the capability to debug the dbgp driver The dbgp_ehci_status() was added in a number of places to report the critical ehci registers to diagnose the cause of a failure of the ehci-dbgp driver. 2) Capability to survive the host controller initialization The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were added so as to allow the ehci-dbgp to re-initialize after the ehci host controller is reset by the standard host controller driver. This same routine is common for the early startup or re-initialization. This resulted in the need to move some of the initialization code out of the __init section because the ehci driver has the possibility to be loaded later on as a kernel module. 3) Stability improvements for device initialization The device enumeration from 0 to 127 has the possibility to fail the first time after a warm reset on some older EHCI debug controllers. The enumeration will be tried up to 3 times to account for this failure case. The dbg_wait_until_complete() was changed to wait up to 250 ms before failing which only comes into play during device initialization. The maximum delay will never get hit during the course of normal operation of the driver, unless the device got unplugged or there was a ehci controller failure, in which case the dbgp device driver will shut itself down. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: dbrownell@users.sourceforge.net Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-21 04:39:53 +08:00
/* Move the device to 127 if it isn't already there */
if (devnum != USB_DEBUG_DEVNUM) {
ret = dbgp_control_msg(devnum,
USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
USB_REQ_SET_ADDRESS, USB_DEBUG_DEVNUM, 0, NULL, 0);
if (ret < 0) {
dbgp_printk("Could not move attached device to %d\n",
USB_DEBUG_DEVNUM);
goto err;
}
dbgp_printk("debug device renamed to 127\n");
}
/* Enable the debug interface */
ret = dbgp_control_msg(USB_DEBUG_DEVNUM,
USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
USB_REQ_SET_FEATURE, USB_DEVICE_DEBUG_MODE, 0, NULL, 0);
if (ret < 0) {
dbgp_printk(" Could not enable the debug device\n");
goto err;
}
dbgp_printk("debug interface enabled\n");
/* Perform a small write to get the even/odd data state in sync
*/
ret = dbgp_bulk_write(USB_DEBUG_DEVNUM, dbgp_endpoint_out, " ", 1);
if (ret < 0) {
dbgp_printk("dbgp_bulk_write failed: %d\n", ret);
goto err;
}
dbgp_printk("small write done\n");
USB: ehci-dbgp: stability improvements and external re-init This patch implements several changes: 1) Improve the capability to debug the dbgp driver The dbgp_ehci_status() was added in a number of places to report the critical ehci registers to diagnose the cause of a failure of the ehci-dbgp driver. 2) Capability to survive the host controller initialization The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were added so as to allow the ehci-dbgp to re-initialize after the ehci host controller is reset by the standard host controller driver. This same routine is common for the early startup or re-initialization. This resulted in the need to move some of the initialization code out of the __init section because the ehci driver has the possibility to be loaded later on as a kernel module. 3) Stability improvements for device initialization The device enumeration from 0 to 127 has the possibility to fail the first time after a warm reset on some older EHCI debug controllers. The enumeration will be tried up to 3 times to account for this failure case. The dbg_wait_until_complete() was changed to wait up to 250 ms before failing which only comes into play during device initialization. The maximum delay will never get hit during the course of normal operation of the driver, unless the device got unplugged or there was a ehci controller failure, in which case the dbgp device driver will shut itself down. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: dbrownell@users.sourceforge.net Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-21 04:39:53 +08:00
dbgp_not_safe = 0;
return 0;
err:
if (tries--)
goto try_again;
return -ENODEV;
}
static int ehci_reset_port(int port)
{
u32 portsc;
u32 delay_time, delay;
int loop;
USB: ehci-dbgp: stability improvements and external re-init This patch implements several changes: 1) Improve the capability to debug the dbgp driver The dbgp_ehci_status() was added in a number of places to report the critical ehci registers to diagnose the cause of a failure of the ehci-dbgp driver. 2) Capability to survive the host controller initialization The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were added so as to allow the ehci-dbgp to re-initialize after the ehci host controller is reset by the standard host controller driver. This same routine is common for the early startup or re-initialization. This resulted in the need to move some of the initialization code out of the __init section because the ehci driver has the possibility to be loaded later on as a kernel module. 3) Stability improvements for device initialization The device enumeration from 0 to 127 has the possibility to fail the first time after a warm reset on some older EHCI debug controllers. The enumeration will be tried up to 3 times to account for this failure case. The dbg_wait_until_complete() was changed to wait up to 250 ms before failing which only comes into play during device initialization. The maximum delay will never get hit during the course of normal operation of the driver, unless the device got unplugged or there was a ehci controller failure, in which case the dbgp device driver will shut itself down. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: dbrownell@users.sourceforge.net Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-21 04:39:53 +08:00
dbgp_ehci_status("reset port");
/* Reset the usb debug port */
portsc = readl(&ehci_regs->port_status[port - 1]);
portsc &= ~PORT_PE;
portsc |= PORT_RESET;
writel(portsc, &ehci_regs->port_status[port - 1]);
delay = HUB_ROOT_RESET_TIME;
for (delay_time = 0; delay_time < HUB_RESET_TIMEOUT;
delay_time += delay) {
dbgp_mdelay(delay);
portsc = readl(&ehci_regs->port_status[port - 1]);
if (!(portsc & PORT_RESET))
break;
}
if (portsc & PORT_RESET) {
/* force reset to complete */
loop = 100 * 1000;
writel(portsc & ~(PORT_RWC_BITS | PORT_RESET),
&ehci_regs->port_status[port - 1]);
do {
udelay(1);
portsc = readl(&ehci_regs->port_status[port-1]);
} while ((portsc & PORT_RESET) && (--loop > 0));
}
/* Device went away? */
if (!(portsc & PORT_CONNECT))
return -ENOTCONN;
/* bomb out completely if something weird happened */
if ((portsc & PORT_CSC))
return -EINVAL;
/* If we've finished resetting, then break out of the loop */
if (!(portsc & PORT_RESET) && (portsc & PORT_PE))
return 0;
return -EBUSY;
}
USB: ehci-dbgp: stability improvements and external re-init This patch implements several changes: 1) Improve the capability to debug the dbgp driver The dbgp_ehci_status() was added in a number of places to report the critical ehci registers to diagnose the cause of a failure of the ehci-dbgp driver. 2) Capability to survive the host controller initialization The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were added so as to allow the ehci-dbgp to re-initialize after the ehci host controller is reset by the standard host controller driver. This same routine is common for the early startup or re-initialization. This resulted in the need to move some of the initialization code out of the __init section because the ehci driver has the possibility to be loaded later on as a kernel module. 3) Stability improvements for device initialization The device enumeration from 0 to 127 has the possibility to fail the first time after a warm reset on some older EHCI debug controllers. The enumeration will be tried up to 3 times to account for this failure case. The dbg_wait_until_complete() was changed to wait up to 250 ms before failing which only comes into play during device initialization. The maximum delay will never get hit during the course of normal operation of the driver, unless the device got unplugged or there was a ehci controller failure, in which case the dbgp device driver will shut itself down. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: dbrownell@users.sourceforge.net Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-21 04:39:53 +08:00
static int ehci_wait_for_port(int port)
{
u32 status;
int ret, reps;
for (reps = 0; reps < 300; reps++) {
status = readl(&ehci_regs->status);
if (status & STS_PCD)
break;
dbgp_mdelay(1);
}
ret = ehci_reset_port(port);
if (ret == 0)
return 0;
return -ENOTCONN;
}
typedef void (*set_debug_port_t)(int port);
static void __init default_set_debug_port(int port)
{
}
static set_debug_port_t __initdata set_debug_port = default_set_debug_port;
static void __init nvidia_set_debug_port(int port)
{
u32 dword;
dword = read_pci_config(ehci_dev.bus, ehci_dev.slot, ehci_dev.func,
0x74);
dword &= ~(0x0f<<12);
dword |= ((port & 0x0f)<<12);
write_pci_config(ehci_dev.bus, ehci_dev.slot, ehci_dev.func, 0x74,
dword);
dbgp_printk("set debug port to %d\n", port);
}
static void __init detect_set_debug_port(void)
{
u32 vendorid;
vendorid = read_pci_config(ehci_dev.bus, ehci_dev.slot, ehci_dev.func,
0x00);
if ((vendorid & 0xffff) == 0x10de) {
dbgp_printk("using nvidia set_debug_port\n");
set_debug_port = nvidia_set_debug_port;
}
}
/* The code in early_ehci_bios_handoff() is derived from the usb pci
* quirk initialization, but altered so as to use the early PCI
* routines. */
#define EHCI_USBLEGSUP_BIOS (1 << 16) /* BIOS semaphore */
#define EHCI_USBLEGCTLSTS 4 /* legacy control/status */
static void __init early_ehci_bios_handoff(void)
{
u32 hcc_params = readl(&ehci_caps->hcc_params);
int offset = (hcc_params >> 8) & 0xff;
u32 cap;
int msec;
if (!offset)
return;
cap = read_pci_config(ehci_dev.bus, ehci_dev.slot,
ehci_dev.func, offset);
dbgp_printk("dbgp: ehci BIOS state %08x\n", cap);
if ((cap & 0xff) == 1 && (cap & EHCI_USBLEGSUP_BIOS)) {
dbgp_printk("dbgp: BIOS handoff\n");
write_pci_config_byte(ehci_dev.bus, ehci_dev.slot,
ehci_dev.func, offset + 3, 1);
}
/* if boot firmware now owns EHCI, spin till it hands it over. */
msec = 1000;
while ((cap & EHCI_USBLEGSUP_BIOS) && (msec > 0)) {
mdelay(10);
msec -= 10;
cap = read_pci_config(ehci_dev.bus, ehci_dev.slot,
ehci_dev.func, offset);
}
if (cap & EHCI_USBLEGSUP_BIOS) {
/* well, possibly buggy BIOS... try to shut it down,
* and hope nothing goes too wrong */
dbgp_printk("dbgp: BIOS handoff failed: %08x\n", cap);
write_pci_config_byte(ehci_dev.bus, ehci_dev.slot,
ehci_dev.func, offset + 2, 0);
}
/* just in case, always disable EHCI SMIs */
write_pci_config_byte(ehci_dev.bus, ehci_dev.slot, ehci_dev.func,
offset + EHCI_USBLEGCTLSTS, 0);
}
static int __init ehci_setup(void)
{
USB: ehci-dbgp: stability improvements and external re-init This patch implements several changes: 1) Improve the capability to debug the dbgp driver The dbgp_ehci_status() was added in a number of places to report the critical ehci registers to diagnose the cause of a failure of the ehci-dbgp driver. 2) Capability to survive the host controller initialization The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were added so as to allow the ehci-dbgp to re-initialize after the ehci host controller is reset by the standard host controller driver. This same routine is common for the early startup or re-initialization. This resulted in the need to move some of the initialization code out of the __init section because the ehci driver has the possibility to be loaded later on as a kernel module. 3) Stability improvements for device initialization The device enumeration from 0 to 127 has the possibility to fail the first time after a warm reset on some older EHCI debug controllers. The enumeration will be tried up to 3 times to account for this failure case. The dbg_wait_until_complete() was changed to wait up to 250 ms before failing which only comes into play during device initialization. The maximum delay will never get hit during the course of normal operation of the driver, unless the device got unplugged or there was a ehci controller failure, in which case the dbgp device driver will shut itself down. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: dbrownell@users.sourceforge.net Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-21 04:39:53 +08:00
u32 ctrl, portsc, hcs_params;
u32 debug_port, new_debug_port = 0, n_ports;
int ret, i;
int port_map_tried;
int playtimes = 3;
early_ehci_bios_handoff();
try_next_time:
port_map_tried = 0;
try_next_port:
hcs_params = readl(&ehci_caps->hcs_params);
debug_port = HCS_DEBUG_PORT(hcs_params);
USB: ehci-dbgp: stability improvements and external re-init This patch implements several changes: 1) Improve the capability to debug the dbgp driver The dbgp_ehci_status() was added in a number of places to report the critical ehci registers to diagnose the cause of a failure of the ehci-dbgp driver. 2) Capability to survive the host controller initialization The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were added so as to allow the ehci-dbgp to re-initialize after the ehci host controller is reset by the standard host controller driver. This same routine is common for the early startup or re-initialization. This resulted in the need to move some of the initialization code out of the __init section because the ehci driver has the possibility to be loaded later on as a kernel module. 3) Stability improvements for device initialization The device enumeration from 0 to 127 has the possibility to fail the first time after a warm reset on some older EHCI debug controllers. The enumeration will be tried up to 3 times to account for this failure case. The dbg_wait_until_complete() was changed to wait up to 250 ms before failing which only comes into play during device initialization. The maximum delay will never get hit during the course of normal operation of the driver, unless the device got unplugged or there was a ehci controller failure, in which case the dbgp device driver will shut itself down. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: dbrownell@users.sourceforge.net Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-21 04:39:53 +08:00
dbgp_phys_port = debug_port;
n_ports = HCS_N_PORTS(hcs_params);
dbgp_printk("debug_port: %d\n", debug_port);
dbgp_printk("n_ports: %d\n", n_ports);
USB: ehci-dbgp: stability improvements and external re-init This patch implements several changes: 1) Improve the capability to debug the dbgp driver The dbgp_ehci_status() was added in a number of places to report the critical ehci registers to diagnose the cause of a failure of the ehci-dbgp driver. 2) Capability to survive the host controller initialization The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were added so as to allow the ehci-dbgp to re-initialize after the ehci host controller is reset by the standard host controller driver. This same routine is common for the early startup or re-initialization. This resulted in the need to move some of the initialization code out of the __init section because the ehci driver has the possibility to be loaded later on as a kernel module. 3) Stability improvements for device initialization The device enumeration from 0 to 127 has the possibility to fail the first time after a warm reset on some older EHCI debug controllers. The enumeration will be tried up to 3 times to account for this failure case. The dbg_wait_until_complete() was changed to wait up to 250 ms before failing which only comes into play during device initialization. The maximum delay will never get hit during the course of normal operation of the driver, unless the device got unplugged or there was a ehci controller failure, in which case the dbgp device driver will shut itself down. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: dbrownell@users.sourceforge.net Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-21 04:39:53 +08:00
dbgp_ehci_status("");
for (i = 1; i <= n_ports; i++) {
portsc = readl(&ehci_regs->port_status[i-1]);
dbgp_printk("portstatus%d: %08x\n", i, portsc);
}
if (port_map_tried && (new_debug_port != debug_port)) {
if (--playtimes) {
set_debug_port(new_debug_port);
goto try_next_time;
}
return -1;
}
USB: ehci-dbgp: stability improvements and external re-init This patch implements several changes: 1) Improve the capability to debug the dbgp driver The dbgp_ehci_status() was added in a number of places to report the critical ehci registers to diagnose the cause of a failure of the ehci-dbgp driver. 2) Capability to survive the host controller initialization The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were added so as to allow the ehci-dbgp to re-initialize after the ehci host controller is reset by the standard host controller driver. This same routine is common for the early startup or re-initialization. This resulted in the need to move some of the initialization code out of the __init section because the ehci driver has the possibility to be loaded later on as a kernel module. 3) Stability improvements for device initialization The device enumeration from 0 to 127 has the possibility to fail the first time after a warm reset on some older EHCI debug controllers. The enumeration will be tried up to 3 times to account for this failure case. The dbg_wait_until_complete() was changed to wait up to 250 ms before failing which only comes into play during device initialization. The maximum delay will never get hit during the course of normal operation of the driver, unless the device got unplugged or there was a ehci controller failure, in which case the dbgp device driver will shut itself down. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: dbrownell@users.sourceforge.net Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-21 04:39:53 +08:00
/* Only reset the controller if it is not already in the
* configured state */
if (!(readl(&ehci_regs->configured_flag) & FLAG_CF)) {
if (dbgp_ehci_controller_reset() != 0)
return -1;
} else {
dbgp_ehci_status("ehci skip - already configured");
}
ret = _dbgp_external_startup();
USB: ehci-dbgp: stability improvements and external re-init This patch implements several changes: 1) Improve the capability to debug the dbgp driver The dbgp_ehci_status() was added in a number of places to report the critical ehci registers to diagnose the cause of a failure of the ehci-dbgp driver. 2) Capability to survive the host controller initialization The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were added so as to allow the ehci-dbgp to re-initialize after the ehci host controller is reset by the standard host controller driver. This same routine is common for the early startup or re-initialization. This resulted in the need to move some of the initialization code out of the __init section because the ehci driver has the possibility to be loaded later on as a kernel module. 3) Stability improvements for device initialization The device enumeration from 0 to 127 has the possibility to fail the first time after a warm reset on some older EHCI debug controllers. The enumeration will be tried up to 3 times to account for this failure case. The dbg_wait_until_complete() was changed to wait up to 250 ms before failing which only comes into play during device initialization. The maximum delay will never get hit during the course of normal operation of the driver, unless the device got unplugged or there was a ehci controller failure, in which case the dbgp device driver will shut itself down. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: dbrownell@users.sourceforge.net Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-21 04:39:53 +08:00
if (ret == -EIO)
goto next_debug_port;
if (ret < 0) {
USB: ehci-dbgp: stability improvements and external re-init This patch implements several changes: 1) Improve the capability to debug the dbgp driver The dbgp_ehci_status() was added in a number of places to report the critical ehci registers to diagnose the cause of a failure of the ehci-dbgp driver. 2) Capability to survive the host controller initialization The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were added so as to allow the ehci-dbgp to re-initialize after the ehci host controller is reset by the standard host controller driver. This same routine is common for the early startup or re-initialization. This resulted in the need to move some of the initialization code out of the __init section because the ehci driver has the possibility to be loaded later on as a kernel module. 3) Stability improvements for device initialization The device enumeration from 0 to 127 has the possibility to fail the first time after a warm reset on some older EHCI debug controllers. The enumeration will be tried up to 3 times to account for this failure case. The dbg_wait_until_complete() was changed to wait up to 250 ms before failing which only comes into play during device initialization. The maximum delay will never get hit during the course of normal operation of the driver, unless the device got unplugged or there was a ehci controller failure, in which case the dbgp device driver will shut itself down. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: dbrownell@users.sourceforge.net Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-21 04:39:53 +08:00
/* Things didn't work so remove my claim */
ctrl = readl(&ehci_debug->control);
ctrl &= ~(DBGP_CLAIM | DBGP_OUT);
writel(ctrl, &ehci_debug->control);
return -1;
}
return 0;
next_debug_port:
port_map_tried |= (1<<(debug_port - 1));
new_debug_port = ((debug_port-1+1)%n_ports) + 1;
if (port_map_tried != ((1<<n_ports) - 1)) {
set_debug_port(new_debug_port);
goto try_next_port;
}
if (--playtimes) {
set_debug_port(new_debug_port);
goto try_next_time;
}
return -1;
}
int __init early_dbgp_init(char *s)
{
u32 debug_port, bar, offset;
u32 bus, slot, func, cap;
void __iomem *ehci_bar;
u32 dbgp_num;
u32 bar_val;
char *e;
int ret;
u8 byte;
if (!early_pci_allowed())
return -1;
dbgp_num = 0;
if (*s)
dbgp_num = simple_strtoul(s, &e, 10);
dbgp_printk("dbgp_num: %d\n", dbgp_num);
cap = find_dbgp(dbgp_num, &bus, &slot, &func);
if (!cap)
return -1;
dbgp_printk("Found EHCI debug port on %02x:%02x.%1x\n", bus, slot,
func);
debug_port = read_pci_config(bus, slot, func, cap);
bar = (debug_port >> 29) & 0x7;
bar = (bar * 4) + 0xc;
offset = (debug_port >> 16) & 0xfff;
dbgp_printk("bar: %02x offset: %03x\n", bar, offset);
if (bar != PCI_BASE_ADDRESS_0) {
dbgp_printk("only debug ports on bar 1 handled.\n");
return -1;
}
bar_val = read_pci_config(bus, slot, func, PCI_BASE_ADDRESS_0);
dbgp_printk("bar_val: %02x offset: %03x\n", bar_val, offset);
if (bar_val & ~PCI_BASE_ADDRESS_MEM_MASK) {
dbgp_printk("only simple 32bit mmio bars supported\n");
return -1;
}
/* double check if the mem space is enabled */
byte = read_pci_config_byte(bus, slot, func, 0x04);
if (!(byte & 0x2)) {
byte |= 0x02;
write_pci_config_byte(bus, slot, func, 0x04, byte);
dbgp_printk("mmio for ehci enabled\n");
}
/*
* FIXME I don't have the bar size so just guess PAGE_SIZE is more
* than enough. 1K is the biggest I have seen.
*/
set_fixmap_nocache(FIX_DBGP_BASE, bar_val & PAGE_MASK);
ehci_bar = (void __iomem *)__fix_to_virt(FIX_DBGP_BASE);
ehci_bar += bar_val & ~PAGE_MASK;
dbgp_printk("ehci_bar: %p\n", ehci_bar);
ehci_caps = ehci_bar;
ehci_regs = ehci_bar + EARLY_HC_LENGTH(readl(&ehci_caps->hc_capbase));
ehci_debug = ehci_bar + offset;
ehci_dev.bus = bus;
ehci_dev.slot = slot;
ehci_dev.func = func;
detect_set_debug_port();
ret = ehci_setup();
if (ret < 0) {
dbgp_printk("ehci_setup failed\n");
ehci_debug = NULL;
return -1;
}
USB: ehci-dbgp: stability improvements and external re-init This patch implements several changes: 1) Improve the capability to debug the dbgp driver The dbgp_ehci_status() was added in a number of places to report the critical ehci registers to diagnose the cause of a failure of the ehci-dbgp driver. 2) Capability to survive the host controller initialization The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were added so as to allow the ehci-dbgp to re-initialize after the ehci host controller is reset by the standard host controller driver. This same routine is common for the early startup or re-initialization. This resulted in the need to move some of the initialization code out of the __init section because the ehci driver has the possibility to be loaded later on as a kernel module. 3) Stability improvements for device initialization The device enumeration from 0 to 127 has the possibility to fail the first time after a warm reset on some older EHCI debug controllers. The enumeration will be tried up to 3 times to account for this failure case. The dbg_wait_until_complete() was changed to wait up to 250 ms before failing which only comes into play during device initialization. The maximum delay will never get hit during the course of normal operation of the driver, unless the device got unplugged or there was a ehci controller failure, in which case the dbgp device driver will shut itself down. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: dbrownell@users.sourceforge.net Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-21 04:39:53 +08:00
dbgp_ehci_status("early_init_complete");
return 0;
}
static void early_dbgp_write(struct console *con, const char *str, u32 n)
{
int chunk, ret;
char buf[DBGP_MAX_PACKET];
int use_cr = 0;
USB: ehci-dbgp: stability improvements and external re-init This patch implements several changes: 1) Improve the capability to debug the dbgp driver The dbgp_ehci_status() was added in a number of places to report the critical ehci registers to diagnose the cause of a failure of the ehci-dbgp driver. 2) Capability to survive the host controller initialization The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were added so as to allow the ehci-dbgp to re-initialize after the ehci host controller is reset by the standard host controller driver. This same routine is common for the early startup or re-initialization. This resulted in the need to move some of the initialization code out of the __init section because the ehci driver has the possibility to be loaded later on as a kernel module. 3) Stability improvements for device initialization The device enumeration from 0 to 127 has the possibility to fail the first time after a warm reset on some older EHCI debug controllers. The enumeration will be tried up to 3 times to account for this failure case. The dbg_wait_until_complete() was changed to wait up to 250 ms before failing which only comes into play during device initialization. The maximum delay will never get hit during the course of normal operation of the driver, unless the device got unplugged or there was a ehci controller failure, in which case the dbgp device driver will shut itself down. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: dbrownell@users.sourceforge.net Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-21 04:39:53 +08:00
u32 cmd, ctrl;
int reset_run = 0;
USB: ehci-dbgp: stability improvements and external re-init This patch implements several changes: 1) Improve the capability to debug the dbgp driver The dbgp_ehci_status() was added in a number of places to report the critical ehci registers to diagnose the cause of a failure of the ehci-dbgp driver. 2) Capability to survive the host controller initialization The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were added so as to allow the ehci-dbgp to re-initialize after the ehci host controller is reset by the standard host controller driver. This same routine is common for the early startup or re-initialization. This resulted in the need to move some of the initialization code out of the __init section because the ehci driver has the possibility to be loaded later on as a kernel module. 3) Stability improvements for device initialization The device enumeration from 0 to 127 has the possibility to fail the first time after a warm reset on some older EHCI debug controllers. The enumeration will be tried up to 3 times to account for this failure case. The dbg_wait_until_complete() was changed to wait up to 250 ms before failing which only comes into play during device initialization. The maximum delay will never get hit during the course of normal operation of the driver, unless the device got unplugged or there was a ehci controller failure, in which case the dbgp device driver will shut itself down. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: dbrownell@users.sourceforge.net Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-21 04:39:53 +08:00
if (!ehci_debug || dbgp_not_safe)
return;
USB: ehci-dbgp: stability improvements and external re-init This patch implements several changes: 1) Improve the capability to debug the dbgp driver The dbgp_ehci_status() was added in a number of places to report the critical ehci registers to diagnose the cause of a failure of the ehci-dbgp driver. 2) Capability to survive the host controller initialization The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were added so as to allow the ehci-dbgp to re-initialize after the ehci host controller is reset by the standard host controller driver. This same routine is common for the early startup or re-initialization. This resulted in the need to move some of the initialization code out of the __init section because the ehci driver has the possibility to be loaded later on as a kernel module. 3) Stability improvements for device initialization The device enumeration from 0 to 127 has the possibility to fail the first time after a warm reset on some older EHCI debug controllers. The enumeration will be tried up to 3 times to account for this failure case. The dbg_wait_until_complete() was changed to wait up to 250 ms before failing which only comes into play during device initialization. The maximum delay will never get hit during the course of normal operation of the driver, unless the device got unplugged or there was a ehci controller failure, in which case the dbgp device driver will shut itself down. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: dbrownell@users.sourceforge.net Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-21 04:39:53 +08:00
cmd = readl(&ehci_regs->command);
if (unlikely(!(cmd & CMD_RUN))) {
/* If the ehci controller is not in the run state do extended
* checks to see if the acpi or some other initialization also
* reset the ehci debug port */
ctrl = readl(&ehci_debug->control);
if (!(ctrl & DBGP_ENABLED)) {
dbgp_not_safe = 1;
_dbgp_external_startup();
USB: ehci-dbgp: stability improvements and external re-init This patch implements several changes: 1) Improve the capability to debug the dbgp driver The dbgp_ehci_status() was added in a number of places to report the critical ehci registers to diagnose the cause of a failure of the ehci-dbgp driver. 2) Capability to survive the host controller initialization The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were added so as to allow the ehci-dbgp to re-initialize after the ehci host controller is reset by the standard host controller driver. This same routine is common for the early startup or re-initialization. This resulted in the need to move some of the initialization code out of the __init section because the ehci driver has the possibility to be loaded later on as a kernel module. 3) Stability improvements for device initialization The device enumeration from 0 to 127 has the possibility to fail the first time after a warm reset on some older EHCI debug controllers. The enumeration will be tried up to 3 times to account for this failure case. The dbg_wait_until_complete() was changed to wait up to 250 ms before failing which only comes into play during device initialization. The maximum delay will never get hit during the course of normal operation of the driver, unless the device got unplugged or there was a ehci controller failure, in which case the dbgp device driver will shut itself down. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: dbrownell@users.sourceforge.net Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-21 04:39:53 +08:00
} else {
cmd |= CMD_RUN;
writel(cmd, &ehci_regs->command);
reset_run = 1;
}
}
while (n > 0) {
for (chunk = 0; chunk < DBGP_MAX_PACKET && n > 0;
str++, chunk++, n--) {
if (!use_cr && *str == '\n') {
use_cr = 1;
buf[chunk] = '\r';
str--;
n++;
continue;
}
if (use_cr)
use_cr = 0;
buf[chunk] = *str;
}
USB: ehci-dbgp: stability improvements and external re-init This patch implements several changes: 1) Improve the capability to debug the dbgp driver The dbgp_ehci_status() was added in a number of places to report the critical ehci registers to diagnose the cause of a failure of the ehci-dbgp driver. 2) Capability to survive the host controller initialization The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were added so as to allow the ehci-dbgp to re-initialize after the ehci host controller is reset by the standard host controller driver. This same routine is common for the early startup or re-initialization. This resulted in the need to move some of the initialization code out of the __init section because the ehci driver has the possibility to be loaded later on as a kernel module. 3) Stability improvements for device initialization The device enumeration from 0 to 127 has the possibility to fail the first time after a warm reset on some older EHCI debug controllers. The enumeration will be tried up to 3 times to account for this failure case. The dbg_wait_until_complete() was changed to wait up to 250 ms before failing which only comes into play during device initialization. The maximum delay will never get hit during the course of normal operation of the driver, unless the device got unplugged or there was a ehci controller failure, in which case the dbgp device driver will shut itself down. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: dbrownell@users.sourceforge.net Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-21 04:39:53 +08:00
if (chunk > 0) {
ret = dbgp_bulk_write(USB_DEBUG_DEVNUM,
dbgp_endpoint_out, buf, chunk);
}
}
if (unlikely(reset_run)) {
cmd = readl(&ehci_regs->command);
cmd &= ~CMD_RUN;
writel(cmd, &ehci_regs->command);
}
}
struct console early_dbgp_console = {
.name = "earlydbg",
.write = early_dbgp_write,
.flags = CON_PRINTBUFFER,
.index = -1,
};
#if IS_ENABLED(CONFIG_USB)
int dbgp_reset_prep(struct usb_hcd *hcd)
{
int ret = xen_dbgp_reset_prep(hcd);
u32 ctrl;
if (ret)
return ret;
dbgp_not_safe = 1;
if (!ehci_debug)
return 0;
echi-dbgp: Add kernel debugger support for the usb debug port This patch adds the capability to use the usb debug port with the kernel debugger. It is also still possible to use this functionality with or without the earlyprintk=dbgpX. It is possible to use the kgdbwait boot argument to debug very early in the kernel start up code. There are two ways to use this driver extension with a kernel boot argument. 1) kgdbdbgp=# -- Where # is the number of the usb debug controller You must use sysrq-g to break into the kernel debugger on another connection type other than the dbgp. 2) kgdbdbgp=#debugControlNum#,#Seconds# In this mode, the usb debug port is polled every #Seconds# for character input. It is possible to use gdb or press control-c to break into the kernel debugger. From the implementation perspective there are 3 high level changes. 1) Allow variable retries for the the hardware via dbgp_bulk_read(). The amount of retries for the dbgp_bulk_read() needed to be variable instead of fixed. We do not want to poll at all when the kernel is operating in interrupt driven mode. The polling only occurs if the kernel was booted when specifying some number of seconds via the kgdbdbgp boot argument (IE kgdbdbgp=0,1). In this case the loop count is reduced to 1 so as introduce the smallest amount of latency as possible. 2) Save the bulk IN endpoint address for use by the kgdb code. 3) The addition of the kgdb interface code. This consisted of adding in a character read function for the dbgp as well as a polling thread to allow the dbgp to interrupt the kernel execution. The rest is the typical kgdb I/O api. CC: Eric Biederman <ebiederm@xmission.com> CC: Yinghai Lu <yhlu.kernel@gmail.com> CC: linux-usb@vger.kernel.org Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21 10:04:31 +08:00
if ((early_dbgp_console.index != -1 &&
!(early_dbgp_console.flags & CON_BOOT)) ||
dbgp_kgdb_mode)
return 1;
/* This means the console is not initialized, or should get
* shutdown so as to allow for reuse of the usb device, which
* means it is time to shutdown the usb debug port. */
ctrl = readl(&ehci_debug->control);
if (ctrl & DBGP_ENABLED) {
ctrl &= ~(DBGP_CLAIM);
writel(ctrl, &ehci_debug->control);
}
return 0;
}
EXPORT_SYMBOL_GPL(dbgp_reset_prep);
echi-dbgp: Add kernel debugger support for the usb debug port This patch adds the capability to use the usb debug port with the kernel debugger. It is also still possible to use this functionality with or without the earlyprintk=dbgpX. It is possible to use the kgdbwait boot argument to debug very early in the kernel start up code. There are two ways to use this driver extension with a kernel boot argument. 1) kgdbdbgp=# -- Where # is the number of the usb debug controller You must use sysrq-g to break into the kernel debugger on another connection type other than the dbgp. 2) kgdbdbgp=#debugControlNum#,#Seconds# In this mode, the usb debug port is polled every #Seconds# for character input. It is possible to use gdb or press control-c to break into the kernel debugger. From the implementation perspective there are 3 high level changes. 1) Allow variable retries for the the hardware via dbgp_bulk_read(). The amount of retries for the dbgp_bulk_read() needed to be variable instead of fixed. We do not want to poll at all when the kernel is operating in interrupt driven mode. The polling only occurs if the kernel was booted when specifying some number of seconds via the kgdbdbgp boot argument (IE kgdbdbgp=0,1). In this case the loop count is reduced to 1 so as introduce the smallest amount of latency as possible. 2) Save the bulk IN endpoint address for use by the kgdb code. 3) The addition of the kgdb interface code. This consisted of adding in a character read function for the dbgp as well as a polling thread to allow the dbgp to interrupt the kernel execution. The rest is the typical kgdb I/O api. CC: Eric Biederman <ebiederm@xmission.com> CC: Yinghai Lu <yhlu.kernel@gmail.com> CC: linux-usb@vger.kernel.org Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21 10:04:31 +08:00
int dbgp_external_startup(struct usb_hcd *hcd)
{
return xen_dbgp_external_startup(hcd) ?: _dbgp_external_startup();
}
EXPORT_SYMBOL_GPL(dbgp_external_startup);
#endif /* USB */
echi-dbgp: Add kernel debugger support for the usb debug port This patch adds the capability to use the usb debug port with the kernel debugger. It is also still possible to use this functionality with or without the earlyprintk=dbgpX. It is possible to use the kgdbwait boot argument to debug very early in the kernel start up code. There are two ways to use this driver extension with a kernel boot argument. 1) kgdbdbgp=# -- Where # is the number of the usb debug controller You must use sysrq-g to break into the kernel debugger on another connection type other than the dbgp. 2) kgdbdbgp=#debugControlNum#,#Seconds# In this mode, the usb debug port is polled every #Seconds# for character input. It is possible to use gdb or press control-c to break into the kernel debugger. From the implementation perspective there are 3 high level changes. 1) Allow variable retries for the the hardware via dbgp_bulk_read(). The amount of retries for the dbgp_bulk_read() needed to be variable instead of fixed. We do not want to poll at all when the kernel is operating in interrupt driven mode. The polling only occurs if the kernel was booted when specifying some number of seconds via the kgdbdbgp boot argument (IE kgdbdbgp=0,1). In this case the loop count is reduced to 1 so as introduce the smallest amount of latency as possible. 2) Save the bulk IN endpoint address for use by the kgdb code. 3) The addition of the kgdb interface code. This consisted of adding in a character read function for the dbgp as well as a polling thread to allow the dbgp to interrupt the kernel execution. The rest is the typical kgdb I/O api. CC: Eric Biederman <ebiederm@xmission.com> CC: Yinghai Lu <yhlu.kernel@gmail.com> CC: linux-usb@vger.kernel.org Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21 10:04:31 +08:00
#ifdef CONFIG_KGDB
static char kgdbdbgp_buf[DBGP_MAX_PACKET];
static int kgdbdbgp_buf_sz;
static int kgdbdbgp_buf_idx;
static int kgdbdbgp_loop_cnt = DBGP_LOOPS;
static int kgdbdbgp_read_char(void)
{
int ret;
if (kgdbdbgp_buf_idx < kgdbdbgp_buf_sz) {
char ch = kgdbdbgp_buf[kgdbdbgp_buf_idx++];
return ch;
}
ret = dbgp_bulk_read(USB_DEBUG_DEVNUM, dbgp_endpoint_in,
&kgdbdbgp_buf, DBGP_MAX_PACKET,
kgdbdbgp_loop_cnt);
if (ret <= 0)
return NO_POLL_CHAR;
kgdbdbgp_buf_sz = ret;
kgdbdbgp_buf_idx = 1;
return kgdbdbgp_buf[0];
}
static void kgdbdbgp_write_char(u8 chr)
{
early_dbgp_write(NULL, &chr, 1);
}
static struct kgdb_io kgdbdbgp_io_ops = {
.name = "kgdbdbgp",
.read_char = kgdbdbgp_read_char,
.write_char = kgdbdbgp_write_char,
};
static int kgdbdbgp_wait_time;
static int __init kgdbdbgp_parse_config(char *str)
{
char *ptr;
if (!ehci_debug) {
if (early_dbgp_init(str))
return -1;
}
ptr = strchr(str, ',');
if (ptr) {
ptr++;
kgdbdbgp_wait_time = simple_strtoul(ptr, &ptr, 10);
}
kgdb_register_io_module(&kgdbdbgp_io_ops);
kgdbdbgp_io_ops.is_console = early_dbgp_console.index != -1;
return 0;
}
early_param("kgdbdbgp", kgdbdbgp_parse_config);
static int kgdbdbgp_reader_thread(void *ptr)
{
int ret;
while (readl(&ehci_debug->control) & DBGP_ENABLED) {
kgdbdbgp_loop_cnt = 1;
ret = kgdbdbgp_read_char();
kgdbdbgp_loop_cnt = DBGP_LOOPS;
if (ret != NO_POLL_CHAR) {
if (ret == 0x3 || ret == '$') {
if (ret == '$')
kgdbdbgp_buf_idx--;
kgdb_breakpoint();
}
continue;
}
schedule_timeout_interruptible(kgdbdbgp_wait_time * HZ);
}
return 0;
}
static int __init kgdbdbgp_start_thread(void)
{
if (dbgp_kgdb_mode && kgdbdbgp_wait_time)
kthread_run(kgdbdbgp_reader_thread, NULL, "%s", "dbgp");
return 0;
}
device_initcall(kgdbdbgp_start_thread);
echi-dbgp: Add kernel debugger support for the usb debug port This patch adds the capability to use the usb debug port with the kernel debugger. It is also still possible to use this functionality with or without the earlyprintk=dbgpX. It is possible to use the kgdbwait boot argument to debug very early in the kernel start up code. There are two ways to use this driver extension with a kernel boot argument. 1) kgdbdbgp=# -- Where # is the number of the usb debug controller You must use sysrq-g to break into the kernel debugger on another connection type other than the dbgp. 2) kgdbdbgp=#debugControlNum#,#Seconds# In this mode, the usb debug port is polled every #Seconds# for character input. It is possible to use gdb or press control-c to break into the kernel debugger. From the implementation perspective there are 3 high level changes. 1) Allow variable retries for the the hardware via dbgp_bulk_read(). The amount of retries for the dbgp_bulk_read() needed to be variable instead of fixed. We do not want to poll at all when the kernel is operating in interrupt driven mode. The polling only occurs if the kernel was booted when specifying some number of seconds via the kgdbdbgp boot argument (IE kgdbdbgp=0,1). In this case the loop count is reduced to 1 so as introduce the smallest amount of latency as possible. 2) Save the bulk IN endpoint address for use by the kgdb code. 3) The addition of the kgdb interface code. This consisted of adding in a character read function for the dbgp as well as a polling thread to allow the dbgp to interrupt the kernel execution. The rest is the typical kgdb I/O api. CC: Eric Biederman <ebiederm@xmission.com> CC: Yinghai Lu <yhlu.kernel@gmail.com> CC: linux-usb@vger.kernel.org Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21 10:04:31 +08:00
#endif /* CONFIG_KGDB */