2005-11-10 22:26:51 +08:00
|
|
|
/*
|
2006-10-04 05:01:26 +08:00
|
|
|
* arch/arm/mach-omap2/serial.c
|
2005-11-10 22:26:51 +08:00
|
|
|
*
|
|
|
|
|
* OMAP2 serial support.
|
|
|
|
|
*
|
2008-10-06 20:49:15 +08:00
|
|
|
* Copyright (C) 2005-2008 Nokia Corporation
|
2005-11-10 22:26:51 +08:00
|
|
|
* Author: Paul Mundt <paul.mundt@nokia.com>
|
|
|
|
|
*
|
OMAP3: PM: UART: disable clocks when idle and off-mode support
This patch allows the UART clocks to be disabled when the OMAP UARTs
are inactive, thus permitting the chip to hit retention in idle.
After the expiration of an activity timer, each UART is allowed to
disable its clocks so the system can enter retention. The activity
timer is (re)activated on any UART interrupt, UART wake event or any
IO pad wakeup. The actual disable of the UART clocks is done in the
'prepare_idle' hook called from the OMAP idle loop.
While the activity timer is active, the smart-idle mode of the UART is
also disabled. This is due to a "feature" of the UART module that
after a UART wakeup, the smart-idle mode may be entered before the
UART has communicated the interrupt, or upon TX, an idle mode may be
entered before the TX FIFOs are emptied.
Upon suspend, the 'prepare_suspend' hook cancels any pending activity
timers and allows the clocks to be disabled immediately.
In addition, upon disabling clocks the UART state is saved in case
of an off-mode transition while clocks are off.
Special thanks to Tero Kristo for the initial ideas and first versions
of UART idle support, and to Jouni Hogander for extra testing and
bugfixes.
Tested on OMAP3 (Beagle, RX51, SDP, EVM) and OMAP2 (n810)
Cc: Tero Kristo <tero.kristo@nokia.com>
Cc: Jouni Hogander <jouni.hogander@nokia.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-02-05 02:51:40 +08:00
|
|
|
* Major rework for PM support by Kevin Hilman
|
|
|
|
|
*
|
2005-11-10 22:26:51 +08:00
|
|
|
* Based off of arch/arm/mach-omap/omap1/serial.c
|
|
|
|
|
*
|
2009-05-29 05:16:04 +08:00
|
|
|
* Copyright (C) 2009 Texas Instruments
|
|
|
|
|
* Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com
|
|
|
|
|
*
|
2005-11-10 22:26:51 +08:00
|
|
|
* This file is subject to the terms and conditions of the GNU General Public
|
|
|
|
|
* License. See the file "COPYING" in the main directory of this archive
|
|
|
|
|
* for more details.
|
|
|
|
|
*/
|
|
|
|
|
#include <linux/kernel.h>
|
|
|
|
|
#include <linux/init.h>
|
2006-01-08 00:15:52 +08:00
|
|
|
#include <linux/clk.h>
|
2008-09-06 19:10:45 +08:00
|
|
|
#include <linux/io.h>
|
2010-02-18 16:59:06 +08:00
|
|
|
#include <linux/delay.h>
|
2010-09-27 22:49:38 +08:00
|
|
|
#include <linux/platform_device.h>
|
|
|
|
|
#include <linux/slab.h>
|
2010-09-27 22:49:53 +08:00
|
|
|
#include <linux/pm_runtime.h>
|
OMAP2+: PM/serial: hold console semaphore while OMAP UARTs are disabled
The console semaphore must be held while the OMAP UART devices are
disabled, lest a console write cause an ARM abort (and a kernel crash)
when the underlying console device is inaccessible. These crashes
only occur when the console is on one of the OMAP internal serial
ports.
While this problem has been latent in the PM idle loop for some time,
the crash was not triggerable with an unmodified kernel until commit
6f251e9db1093c187addc309b5f2f7fe3efd2995 ("OMAP: UART: omap_device
conversions, remove implicit 8520 assumptions"). After this patch, a
console write often occurs after the console UART has been disabled in
the idle loop, crashing the system. Several users have encountered
this bug:
http://www.mail-archive.com/linux-omap@vger.kernel.org/msg38396.html
http://www.mail-archive.com/linux-omap@vger.kernel.org/msg36602.html
The same commit also introduced new code that disabled the UARTs
during init, in omap_serial_init_port(). The kernel will also crash
in this code when earlyconsole and extra debugging is enabled:
http://www.mail-archive.com/linux-omap@vger.kernel.org/msg36411.html
The minimal fix for the -rc series is to hold the console semaphore
while the OMAP UARTs are disabled. This is a somewhat overbroad fix,
since the console may not be located on an OMAP UART, as is the case
with the GPMC UART on Zoom3. While it is technically possible to
determine which devices the console or earlyconsole is actually
running on, it is not a trivial problem to solve, and the code to do
so is not really appropriate for the -rc series.
The right long-term fix is to ensure that no code outside of the OMAP
serial driver can disable an OMAP UART. As I understand it, code to
implement this is under development by TI.
This patch is a collaboration between Paul Walmsley <paul@pwsan.com>
and Tony Lindgren <tony@atomide.com>. Thanks to Ming Lei
<tom.leiming@gmail.com> and Pramod <pramod.gurav@ti.com> for their
feedback on earlier versions of this patch.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Acked-by: Kevin Hilman <khilman@deeprootsystems.com>
Cc: Ming Lei <tom.leiming@gmail.com>
Cc: Pramod <pramod.gurav@ti.com>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Jean Pihet <jean.pihet@newoldbits.com>
Cc: Govindraj.R <govindraj.raja@ti.com>
2010-11-25 07:49:05 +08:00
|
|
|
#include <linux/console.h>
|
2012-12-01 00:41:50 +08:00
|
|
|
#include <linux/omap-dma.h>
|
2012-12-15 01:09:11 +08:00
|
|
|
#include <linux/platform_data/serial-omap.h>
|
OMAP3: PM: UART: disable clocks when idle and off-mode support
This patch allows the UART clocks to be disabled when the OMAP UARTs
are inactive, thus permitting the chip to hit retention in idle.
After the expiration of an activity timer, each UART is allowed to
disable its clocks so the system can enter retention. The activity
timer is (re)activated on any UART interrupt, UART wake event or any
IO pad wakeup. The actual disable of the UART clocks is done in the
'prepare_idle' hook called from the OMAP idle loop.
While the activity timer is active, the smart-idle mode of the UART is
also disabled. This is due to a "feature" of the UART module that
after a UART wakeup, the smart-idle mode may be entered before the
UART has communicated the interrupt, or upon TX, an idle mode may be
entered before the TX FIFOs are emptied.
Upon suspend, the 'prepare_suspend' hook cancels any pending activity
timers and allows the clocks to be disabled immediately.
In addition, upon disabling clocks the UART state is saved in case
of an off-mode transition while clocks are off.
Special thanks to Tero Kristo for the initial ideas and first versions
of UART idle support, and to Jouni Hogander for extra testing and
bugfixes.
Tested on OMAP3 (Beagle, RX51, SDP, EVM) and OMAP2 (n810)
Cc: Tero Kristo <tero.kristo@nokia.com>
Cc: Jouni Hogander <jouni.hogander@nokia.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-02-05 02:51:40 +08:00
|
|
|
|
2012-10-03 08:41:35 +08:00
|
|
|
#include "common.h"
|
|
|
|
|
#include "omap_hwmod.h"
|
|
|
|
|
#include "omap_device.h"
|
2012-10-04 07:36:40 +08:00
|
|
|
#include "omap-pm.h"
|
2012-10-06 04:25:59 +08:00
|
|
|
#include "soc.h"
|
2010-12-22 06:30:55 +08:00
|
|
|
#include "prm2xxx_3xxx.h"
|
OMAP3: PM: UART: disable clocks when idle and off-mode support
This patch allows the UART clocks to be disabled when the OMAP UARTs
are inactive, thus permitting the chip to hit retention in idle.
After the expiration of an activity timer, each UART is allowed to
disable its clocks so the system can enter retention. The activity
timer is (re)activated on any UART interrupt, UART wake event or any
IO pad wakeup. The actual disable of the UART clocks is done in the
'prepare_idle' hook called from the OMAP idle loop.
While the activity timer is active, the smart-idle mode of the UART is
also disabled. This is due to a "feature" of the UART module that
after a UART wakeup, the smart-idle mode may be entered before the
UART has communicated the interrupt, or upon TX, an idle mode may be
entered before the TX FIFOs are emptied.
Upon suspend, the 'prepare_suspend' hook cancels any pending activity
timers and allows the clocks to be disabled immediately.
In addition, upon disabling clocks the UART state is saved in case
of an off-mode transition while clocks are off.
Special thanks to Tero Kristo for the initial ideas and first versions
of UART idle support, and to Jouni Hogander for extra testing and
bugfixes.
Tested on OMAP3 (Beagle, RX51, SDP, EVM) and OMAP2 (n810)
Cc: Tero Kristo <tero.kristo@nokia.com>
Cc: Jouni Hogander <jouni.hogander@nokia.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-02-05 02:51:40 +08:00
|
|
|
#include "pm.h"
|
2010-12-22 06:30:55 +08:00
|
|
|
#include "cm2xxx_3xxx.h"
|
OMAP3: PM: UART: disable clocks when idle and off-mode support
This patch allows the UART clocks to be disabled when the OMAP UARTs
are inactive, thus permitting the chip to hit retention in idle.
After the expiration of an activity timer, each UART is allowed to
disable its clocks so the system can enter retention. The activity
timer is (re)activated on any UART interrupt, UART wake event or any
IO pad wakeup. The actual disable of the UART clocks is done in the
'prepare_idle' hook called from the OMAP idle loop.
While the activity timer is active, the smart-idle mode of the UART is
also disabled. This is due to a "feature" of the UART module that
after a UART wakeup, the smart-idle mode may be entered before the
UART has communicated the interrupt, or upon TX, an idle mode may be
entered before the TX FIFOs are emptied.
Upon suspend, the 'prepare_suspend' hook cancels any pending activity
timers and allows the clocks to be disabled immediately.
In addition, upon disabling clocks the UART state is saved in case
of an off-mode transition while clocks are off.
Special thanks to Tero Kristo for the initial ideas and first versions
of UART idle support, and to Jouni Hogander for extra testing and
bugfixes.
Tested on OMAP3 (Beagle, RX51, SDP, EVM) and OMAP2 (n810)
Cc: Tero Kristo <tero.kristo@nokia.com>
Cc: Jouni Hogander <jouni.hogander@nokia.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-02-05 02:51:40 +08:00
|
|
|
#include "prm-regbits-34xx.h"
|
2010-10-09 01:40:20 +08:00
|
|
|
#include "control.h"
|
2010-12-23 10:42:35 +08:00
|
|
|
#include "mux.h"
|
2012-10-16 03:50:46 +08:00
|
|
|
#include "serial.h"
|
OMAP3: PM: UART: disable clocks when idle and off-mode support
This patch allows the UART clocks to be disabled when the OMAP UARTs
are inactive, thus permitting the chip to hit retention in idle.
After the expiration of an activity timer, each UART is allowed to
disable its clocks so the system can enter retention. The activity
timer is (re)activated on any UART interrupt, UART wake event or any
IO pad wakeup. The actual disable of the UART clocks is done in the
'prepare_idle' hook called from the OMAP idle loop.
While the activity timer is active, the smart-idle mode of the UART is
also disabled. This is due to a "feature" of the UART module that
after a UART wakeup, the smart-idle mode may be entered before the
UART has communicated the interrupt, or upon TX, an idle mode may be
entered before the TX FIFOs are emptied.
Upon suspend, the 'prepare_suspend' hook cancels any pending activity
timers and allows the clocks to be disabled immediately.
In addition, upon disabling clocks the UART state is saved in case
of an off-mode transition while clocks are off.
Special thanks to Tero Kristo for the initial ideas and first versions
of UART idle support, and to Jouni Hogander for extra testing and
bugfixes.
Tested on OMAP3 (Beagle, RX51, SDP, EVM) and OMAP2 (n810)
Cc: Tero Kristo <tero.kristo@nokia.com>
Cc: Jouni Hogander <jouni.hogander@nokia.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-02-05 02:51:40 +08:00
|
|
|
|
2010-02-02 04:34:31 +08:00
|
|
|
/*
|
2011-11-09 20:03:38 +08:00
|
|
|
* NOTE: By default the serial auto_suspend timeout is disabled as it causes
|
|
|
|
|
* lost characters over the serial ports. This means that the UART clocks will
|
|
|
|
|
* stay on until power/autosuspend_delay is set for the uart from sysfs.
|
|
|
|
|
* This also causes that any deeper omap sleep states are blocked.
|
2010-02-02 04:34:31 +08:00
|
|
|
*/
|
2011-11-09 20:03:38 +08:00
|
|
|
#define DEFAULT_AUTOSUSPEND_DELAY -1
|
OMAP3: PM: UART: disable clocks when idle and off-mode support
This patch allows the UART clocks to be disabled when the OMAP UARTs
are inactive, thus permitting the chip to hit retention in idle.
After the expiration of an activity timer, each UART is allowed to
disable its clocks so the system can enter retention. The activity
timer is (re)activated on any UART interrupt, UART wake event or any
IO pad wakeup. The actual disable of the UART clocks is done in the
'prepare_idle' hook called from the OMAP idle loop.
While the activity timer is active, the smart-idle mode of the UART is
also disabled. This is due to a "feature" of the UART module that
after a UART wakeup, the smart-idle mode may be entered before the
UART has communicated the interrupt, or upon TX, an idle mode may be
entered before the TX FIFOs are emptied.
Upon suspend, the 'prepare_suspend' hook cancels any pending activity
timers and allows the clocks to be disabled immediately.
In addition, upon disabling clocks the UART state is saved in case
of an off-mode transition while clocks are off.
Special thanks to Tero Kristo for the initial ideas and first versions
of UART idle support, and to Jouni Hogander for extra testing and
bugfixes.
Tested on OMAP3 (Beagle, RX51, SDP, EVM) and OMAP2 (n810)
Cc: Tero Kristo <tero.kristo@nokia.com>
Cc: Jouni Hogander <jouni.hogander@nokia.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-02-05 02:51:40 +08:00
|
|
|
|
2010-09-27 22:49:38 +08:00
|
|
|
#define MAX_UART_HWMOD_NAME_LEN 16
|
|
|
|
|
|
OMAP3: PM: UART: disable clocks when idle and off-mode support
This patch allows the UART clocks to be disabled when the OMAP UARTs
are inactive, thus permitting the chip to hit retention in idle.
After the expiration of an activity timer, each UART is allowed to
disable its clocks so the system can enter retention. The activity
timer is (re)activated on any UART interrupt, UART wake event or any
IO pad wakeup. The actual disable of the UART clocks is done in the
'prepare_idle' hook called from the OMAP idle loop.
While the activity timer is active, the smart-idle mode of the UART is
also disabled. This is due to a "feature" of the UART module that
after a UART wakeup, the smart-idle mode may be entered before the
UART has communicated the interrupt, or upon TX, an idle mode may be
entered before the TX FIFOs are emptied.
Upon suspend, the 'prepare_suspend' hook cancels any pending activity
timers and allows the clocks to be disabled immediately.
In addition, upon disabling clocks the UART state is saved in case
of an off-mode transition while clocks are off.
Special thanks to Tero Kristo for the initial ideas and first versions
of UART idle support, and to Jouni Hogander for extra testing and
bugfixes.
Tested on OMAP3 (Beagle, RX51, SDP, EVM) and OMAP2 (n810)
Cc: Tero Kristo <tero.kristo@nokia.com>
Cc: Jouni Hogander <jouni.hogander@nokia.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-02-05 02:51:40 +08:00
|
|
|
struct omap_uart_state {
|
|
|
|
|
int num;
|
|
|
|
|
|
|
|
|
|
struct list_head node;
|
2010-09-27 22:49:38 +08:00
|
|
|
struct omap_hwmod *oh;
|
2012-06-05 19:04:11 +08:00
|
|
|
struct omap_device_pad default_omap_uart_pads[2];
|
OMAP3: PM: UART: disable clocks when idle and off-mode support
This patch allows the UART clocks to be disabled when the OMAP UARTs
are inactive, thus permitting the chip to hit retention in idle.
After the expiration of an activity timer, each UART is allowed to
disable its clocks so the system can enter retention. The activity
timer is (re)activated on any UART interrupt, UART wake event or any
IO pad wakeup. The actual disable of the UART clocks is done in the
'prepare_idle' hook called from the OMAP idle loop.
While the activity timer is active, the smart-idle mode of the UART is
also disabled. This is due to a "feature" of the UART module that
after a UART wakeup, the smart-idle mode may be entered before the
UART has communicated the interrupt, or upon TX, an idle mode may be
entered before the TX FIFOs are emptied.
Upon suspend, the 'prepare_suspend' hook cancels any pending activity
timers and allows the clocks to be disabled immediately.
In addition, upon disabling clocks the UART state is saved in case
of an off-mode transition while clocks are off.
Special thanks to Tero Kristo for the initial ideas and first versions
of UART idle support, and to Jouni Hogander for extra testing and
bugfixes.
Tested on OMAP3 (Beagle, RX51, SDP, EVM) and OMAP2 (n810)
Cc: Tero Kristo <tero.kristo@nokia.com>
Cc: Jouni Hogander <jouni.hogander@nokia.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-02-05 02:51:40 +08:00
|
|
|
};
|
|
|
|
|
|
|
|
|
|
static LIST_HEAD(uart_list);
|
2010-09-27 22:49:38 +08:00
|
|
|
static u8 num_uarts;
|
2011-11-07 21:35:44 +08:00
|
|
|
static u8 console_uart_id = -1;
|
2011-09-21 19:24:12 +08:00
|
|
|
static u8 uart_debug;
|
2005-11-10 22:26:51 +08:00
|
|
|
|
2011-11-09 20:04:49 +08:00
|
|
|
#define DEFAULT_RXDMA_POLLRATE 1 /* RX DMA polling rate (us) */
|
2011-11-09 20:03:38 +08:00
|
|
|
#define DEFAULT_RXDMA_BUFSIZE 4096 /* RX DMA buffer size */
|
2011-11-09 20:04:49 +08:00
|
|
|
#define DEFAULT_RXDMA_TIMEOUT (3 * HZ)/* RX DMA timeout (jiffies) */
|
2011-11-09 20:03:38 +08:00
|
|
|
|
|
|
|
|
static struct omap_uart_port_info omap_serial_default_info[] __initdata = {
|
|
|
|
|
{
|
|
|
|
|
.dma_enabled = false,
|
|
|
|
|
.dma_rx_buf_size = DEFAULT_RXDMA_BUFSIZE,
|
2011-11-09 20:04:49 +08:00
|
|
|
.dma_rx_poll_rate = DEFAULT_RXDMA_POLLRATE,
|
2011-11-09 20:03:38 +08:00
|
|
|
.dma_rx_timeout = DEFAULT_RXDMA_TIMEOUT,
|
|
|
|
|
.autosuspend_timeout = DEFAULT_AUTOSUSPEND_DELAY,
|
|
|
|
|
},
|
|
|
|
|
};
|
|
|
|
|
|
OMAP3: PM: UART: disable clocks when idle and off-mode support
This patch allows the UART clocks to be disabled when the OMAP UARTs
are inactive, thus permitting the chip to hit retention in idle.
After the expiration of an activity timer, each UART is allowed to
disable its clocks so the system can enter retention. The activity
timer is (re)activated on any UART interrupt, UART wake event or any
IO pad wakeup. The actual disable of the UART clocks is done in the
'prepare_idle' hook called from the OMAP idle loop.
While the activity timer is active, the smart-idle mode of the UART is
also disabled. This is due to a "feature" of the UART module that
after a UART wakeup, the smart-idle mode may be entered before the
UART has communicated the interrupt, or upon TX, an idle mode may be
entered before the TX FIFOs are emptied.
Upon suspend, the 'prepare_suspend' hook cancels any pending activity
timers and allows the clocks to be disabled immediately.
In addition, upon disabling clocks the UART state is saved in case
of an off-mode transition while clocks are off.
Special thanks to Tero Kristo for the initial ideas and first versions
of UART idle support, and to Jouni Hogander for extra testing and
bugfixes.
Tested on OMAP3 (Beagle, RX51, SDP, EVM) and OMAP2 (n810)
Cc: Tero Kristo <tero.kristo@nokia.com>
Cc: Jouni Hogander <jouni.hogander@nokia.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-02-05 02:51:40 +08:00
|
|
|
#ifdef CONFIG_PM
|
2012-09-06 20:45:20 +08:00
|
|
|
static void omap_uart_enable_wakeup(struct device *dev, bool enable)
|
OMAP3: PM: UART: disable clocks when idle and off-mode support
This patch allows the UART clocks to be disabled when the OMAP UARTs
are inactive, thus permitting the chip to hit retention in idle.
After the expiration of an activity timer, each UART is allowed to
disable its clocks so the system can enter retention. The activity
timer is (re)activated on any UART interrupt, UART wake event or any
IO pad wakeup. The actual disable of the UART clocks is done in the
'prepare_idle' hook called from the OMAP idle loop.
While the activity timer is active, the smart-idle mode of the UART is
also disabled. This is due to a "feature" of the UART module that
after a UART wakeup, the smart-idle mode may be entered before the
UART has communicated the interrupt, or upon TX, an idle mode may be
entered before the TX FIFOs are emptied.
Upon suspend, the 'prepare_suspend' hook cancels any pending activity
timers and allows the clocks to be disabled immediately.
In addition, upon disabling clocks the UART state is saved in case
of an off-mode transition while clocks are off.
Special thanks to Tero Kristo for the initial ideas and first versions
of UART idle support, and to Jouni Hogander for extra testing and
bugfixes.
Tested on OMAP3 (Beagle, RX51, SDP, EVM) and OMAP2 (n810)
Cc: Tero Kristo <tero.kristo@nokia.com>
Cc: Jouni Hogander <jouni.hogander@nokia.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-02-05 02:51:40 +08:00
|
|
|
{
|
2012-09-06 20:45:20 +08:00
|
|
|
struct platform_device *pdev = to_platform_device(dev);
|
2011-10-13 16:41:09 +08:00
|
|
|
struct omap_device *od = to_omap_device(pdev);
|
OMAP3: PM: UART: disable clocks when idle and off-mode support
This patch allows the UART clocks to be disabled when the OMAP UARTs
are inactive, thus permitting the chip to hit retention in idle.
After the expiration of an activity timer, each UART is allowed to
disable its clocks so the system can enter retention. The activity
timer is (re)activated on any UART interrupt, UART wake event or any
IO pad wakeup. The actual disable of the UART clocks is done in the
'prepare_idle' hook called from the OMAP idle loop.
While the activity timer is active, the smart-idle mode of the UART is
also disabled. This is due to a "feature" of the UART module that
after a UART wakeup, the smart-idle mode may be entered before the
UART has communicated the interrupt, or upon TX, an idle mode may be
entered before the TX FIFOs are emptied.
Upon suspend, the 'prepare_suspend' hook cancels any pending activity
timers and allows the clocks to be disabled immediately.
In addition, upon disabling clocks the UART state is saved in case
of an off-mode transition while clocks are off.
Special thanks to Tero Kristo for the initial ideas and first versions
of UART idle support, and to Jouni Hogander for extra testing and
bugfixes.
Tested on OMAP3 (Beagle, RX51, SDP, EVM) and OMAP2 (n810)
Cc: Tero Kristo <tero.kristo@nokia.com>
Cc: Jouni Hogander <jouni.hogander@nokia.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-02-05 02:51:40 +08:00
|
|
|
|
2011-10-13 16:41:09 +08:00
|
|
|
if (!od)
|
|
|
|
|
return;
|
OMAP3: PM: UART: disable clocks when idle and off-mode support
This patch allows the UART clocks to be disabled when the OMAP UARTs
are inactive, thus permitting the chip to hit retention in idle.
After the expiration of an activity timer, each UART is allowed to
disable its clocks so the system can enter retention. The activity
timer is (re)activated on any UART interrupt, UART wake event or any
IO pad wakeup. The actual disable of the UART clocks is done in the
'prepare_idle' hook called from the OMAP idle loop.
While the activity timer is active, the smart-idle mode of the UART is
also disabled. This is due to a "feature" of the UART module that
after a UART wakeup, the smart-idle mode may be entered before the
UART has communicated the interrupt, or upon TX, an idle mode may be
entered before the TX FIFOs are emptied.
Upon suspend, the 'prepare_suspend' hook cancels any pending activity
timers and allows the clocks to be disabled immediately.
In addition, upon disabling clocks the UART state is saved in case
of an off-mode transition while clocks are off.
Special thanks to Tero Kristo for the initial ideas and first versions
of UART idle support, and to Jouni Hogander for extra testing and
bugfixes.
Tested on OMAP3 (Beagle, RX51, SDP, EVM) and OMAP2 (n810)
Cc: Tero Kristo <tero.kristo@nokia.com>
Cc: Jouni Hogander <jouni.hogander@nokia.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-02-05 02:51:40 +08:00
|
|
|
|
2011-10-13 16:41:09 +08:00
|
|
|
if (enable)
|
|
|
|
|
omap_hwmod_enable_wakeup(od->hwmods[0]);
|
|
|
|
|
else
|
|
|
|
|
omap_hwmod_disable_wakeup(od->hwmods[0]);
|
2008-12-09 19:36:50 +08:00
|
|
|
}
|
|
|
|
|
|
OMAP3: PM: UART: disable clocks when idle and off-mode support
This patch allows the UART clocks to be disabled when the OMAP UARTs
are inactive, thus permitting the chip to hit retention in idle.
After the expiration of an activity timer, each UART is allowed to
disable its clocks so the system can enter retention. The activity
timer is (re)activated on any UART interrupt, UART wake event or any
IO pad wakeup. The actual disable of the UART clocks is done in the
'prepare_idle' hook called from the OMAP idle loop.
While the activity timer is active, the smart-idle mode of the UART is
also disabled. This is due to a "feature" of the UART module that
after a UART wakeup, the smart-idle mode may be entered before the
UART has communicated the interrupt, or upon TX, an idle mode may be
entered before the TX FIFOs are emptied.
Upon suspend, the 'prepare_suspend' hook cancels any pending activity
timers and allows the clocks to be disabled immediately.
In addition, upon disabling clocks the UART state is saved in case
of an off-mode transition while clocks are off.
Special thanks to Tero Kristo for the initial ideas and first versions
of UART idle support, and to Jouni Hogander for extra testing and
bugfixes.
Tested on OMAP3 (Beagle, RX51, SDP, EVM) and OMAP2 (n810)
Cc: Tero Kristo <tero.kristo@nokia.com>
Cc: Jouni Hogander <jouni.hogander@nokia.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-02-05 02:51:40 +08:00
|
|
|
#else
|
2012-09-06 20:45:20 +08:00
|
|
|
static void omap_uart_enable_wakeup(struct device *dev, bool enable)
|
2011-10-13 16:41:09 +08:00
|
|
|
{}
|
OMAP3: PM: UART: disable clocks when idle and off-mode support
This patch allows the UART clocks to be disabled when the OMAP UARTs
are inactive, thus permitting the chip to hit retention in idle.
After the expiration of an activity timer, each UART is allowed to
disable its clocks so the system can enter retention. The activity
timer is (re)activated on any UART interrupt, UART wake event or any
IO pad wakeup. The actual disable of the UART clocks is done in the
'prepare_idle' hook called from the OMAP idle loop.
While the activity timer is active, the smart-idle mode of the UART is
also disabled. This is due to a "feature" of the UART module that
after a UART wakeup, the smart-idle mode may be entered before the
UART has communicated the interrupt, or upon TX, an idle mode may be
entered before the TX FIFOs are emptied.
Upon suspend, the 'prepare_suspend' hook cancels any pending activity
timers and allows the clocks to be disabled immediately.
In addition, upon disabling clocks the UART state is saved in case
of an off-mode transition while clocks are off.
Special thanks to Tero Kristo for the initial ideas and first versions
of UART idle support, and to Jouni Hogander for extra testing and
bugfixes.
Tested on OMAP3 (Beagle, RX51, SDP, EVM) and OMAP2 (n810)
Cc: Tero Kristo <tero.kristo@nokia.com>
Cc: Jouni Hogander <jouni.hogander@nokia.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-02-05 02:51:40 +08:00
|
|
|
#endif /* CONFIG_PM */
|
|
|
|
|
|
2011-11-07 21:25:05 +08:00
|
|
|
#ifdef CONFIG_OMAP_MUX
|
2012-06-05 19:04:11 +08:00
|
|
|
|
|
|
|
|
#define OMAP_UART_DEFAULT_PAD_NAME_LEN 28
|
|
|
|
|
static char rx_pad_name[OMAP_UART_DEFAULT_PAD_NAME_LEN],
|
|
|
|
|
tx_pad_name[OMAP_UART_DEFAULT_PAD_NAME_LEN] __initdata;
|
|
|
|
|
|
|
|
|
|
static void __init
|
|
|
|
|
omap_serial_fill_uart_tx_rx_pads(struct omap_board_data *bdata,
|
|
|
|
|
struct omap_uart_state *uart)
|
|
|
|
|
{
|
|
|
|
|
uart->default_omap_uart_pads[0].name = rx_pad_name;
|
|
|
|
|
uart->default_omap_uart_pads[0].flags = OMAP_DEVICE_PAD_REMUX |
|
|
|
|
|
OMAP_DEVICE_PAD_WAKEUP;
|
|
|
|
|
uart->default_omap_uart_pads[0].enable = OMAP_PIN_INPUT |
|
|
|
|
|
OMAP_MUX_MODE0;
|
|
|
|
|
uart->default_omap_uart_pads[0].idle = OMAP_PIN_INPUT | OMAP_MUX_MODE0;
|
|
|
|
|
uart->default_omap_uart_pads[1].name = tx_pad_name;
|
|
|
|
|
uart->default_omap_uart_pads[1].enable = OMAP_PIN_OUTPUT |
|
|
|
|
|
OMAP_MUX_MODE0;
|
|
|
|
|
bdata->pads = uart->default_omap_uart_pads;
|
|
|
|
|
bdata->pads_cnt = ARRAY_SIZE(uart->default_omap_uart_pads);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static void __init omap_serial_check_wakeup(struct omap_board_data *bdata,
|
|
|
|
|
struct omap_uart_state *uart)
|
2011-11-07 21:25:05 +08:00
|
|
|
{
|
2012-06-05 19:04:11 +08:00
|
|
|
struct omap_mux_partition *tx_partition = NULL, *rx_partition = NULL;
|
|
|
|
|
struct omap_mux *rx_mux = NULL, *tx_mux = NULL;
|
|
|
|
|
char *rx_fmt, *tx_fmt;
|
|
|
|
|
int uart_nr = bdata->id + 1;
|
|
|
|
|
|
|
|
|
|
if (bdata->id != 2) {
|
|
|
|
|
rx_fmt = "uart%d_rx.uart%d_rx";
|
|
|
|
|
tx_fmt = "uart%d_tx.uart%d_tx";
|
|
|
|
|
} else {
|
|
|
|
|
rx_fmt = "uart%d_rx_irrx.uart%d_rx_irrx";
|
|
|
|
|
tx_fmt = "uart%d_tx_irtx.uart%d_tx_irtx";
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
snprintf(rx_pad_name, OMAP_UART_DEFAULT_PAD_NAME_LEN, rx_fmt,
|
|
|
|
|
uart_nr, uart_nr);
|
|
|
|
|
snprintf(tx_pad_name, OMAP_UART_DEFAULT_PAD_NAME_LEN, tx_fmt,
|
|
|
|
|
uart_nr, uart_nr);
|
|
|
|
|
|
|
|
|
|
if (omap_mux_get_by_name(rx_pad_name, &rx_partition, &rx_mux) >= 0 &&
|
|
|
|
|
omap_mux_get_by_name
|
|
|
|
|
(tx_pad_name, &tx_partition, &tx_mux) >= 0) {
|
|
|
|
|
u16 tx_mode, rx_mode;
|
|
|
|
|
|
|
|
|
|
tx_mode = omap_mux_read(tx_partition, tx_mux->reg_offset);
|
|
|
|
|
rx_mode = omap_mux_read(rx_partition, rx_mux->reg_offset);
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* Check if uart is used in default tx/rx mode i.e. in mux mode0
|
|
|
|
|
* if yes then configure rx pin for wake up capability
|
|
|
|
|
*/
|
|
|
|
|
if (OMAP_MODE_UART(rx_mode) && OMAP_MODE_UART(tx_mode))
|
|
|
|
|
omap_serial_fill_uart_tx_rx_pads(bdata, uart);
|
|
|
|
|
}
|
2011-11-07 21:25:05 +08:00
|
|
|
}
|
|
|
|
|
#else
|
2012-06-05 19:04:11 +08:00
|
|
|
static void __init omap_serial_check_wakeup(struct omap_board_data *bdata,
|
|
|
|
|
struct omap_uart_state *uart)
|
|
|
|
|
{
|
|
|
|
|
}
|
2011-11-07 21:25:05 +08:00
|
|
|
#endif
|
|
|
|
|
|
2012-04-13 20:34:26 +08:00
|
|
|
static char *cmdline_find_option(char *str)
|
2011-11-07 21:35:44 +08:00
|
|
|
{
|
|
|
|
|
extern char *saved_command_line;
|
|
|
|
|
|
|
|
|
|
return strstr(saved_command_line, str);
|
|
|
|
|
}
|
|
|
|
|
|
2011-02-15 07:40:20 +08:00
|
|
|
static int __init omap_serial_early_init(void)
|
2005-11-10 22:26:51 +08:00
|
|
|
{
|
2013-06-08 05:55:04 +08:00
|
|
|
if (of_have_populated_dt())
|
|
|
|
|
return -ENODEV;
|
|
|
|
|
|
2010-09-27 22:49:38 +08:00
|
|
|
do {
|
|
|
|
|
char oh_name[MAX_UART_HWMOD_NAME_LEN];
|
|
|
|
|
struct omap_hwmod *oh;
|
|
|
|
|
struct omap_uart_state *uart;
|
2011-11-07 21:35:44 +08:00
|
|
|
char uart_name[MAX_UART_HWMOD_NAME_LEN];
|
2010-02-25 17:40:19 +08:00
|
|
|
|
2010-09-27 22:49:38 +08:00
|
|
|
snprintf(oh_name, MAX_UART_HWMOD_NAME_LEN,
|
2011-10-18 19:02:14 +08:00
|
|
|
"uart%d", num_uarts + 1);
|
2010-09-27 22:49:38 +08:00
|
|
|
oh = omap_hwmod_lookup(oh_name);
|
|
|
|
|
if (!oh)
|
|
|
|
|
break;
|
|
|
|
|
|
|
|
|
|
uart = kzalloc(sizeof(struct omap_uart_state), GFP_KERNEL);
|
|
|
|
|
if (WARN_ON(!uart))
|
2011-02-15 07:40:20 +08:00
|
|
|
return -ENODEV;
|
2005-11-10 22:26:51 +08:00
|
|
|
|
2010-09-27 22:49:38 +08:00
|
|
|
uart->oh = oh;
|
2011-10-18 19:02:14 +08:00
|
|
|
uart->num = num_uarts++;
|
2010-09-27 22:49:38 +08:00
|
|
|
list_add_tail(&uart->node, &uart_list);
|
2011-11-07 21:35:44 +08:00
|
|
|
snprintf(uart_name, MAX_UART_HWMOD_NAME_LEN,
|
|
|
|
|
"%s%d", OMAP_SERIAL_NAME, uart->num);
|
|
|
|
|
|
|
|
|
|
if (cmdline_find_option(uart_name)) {
|
|
|
|
|
console_uart_id = uart->num;
|
2011-10-18 19:39:10 +08:00
|
|
|
|
2011-09-21 19:24:12 +08:00
|
|
|
if (console_loglevel >= 10) {
|
|
|
|
|
uart_debug = true;
|
2012-07-26 14:54:26 +08:00
|
|
|
pr_info("%s used as console in debug mode: uart%d clocks will not be gated",
|
|
|
|
|
uart_name, uart->num);
|
2011-09-21 19:24:12 +08:00
|
|
|
}
|
2011-11-07 21:35:44 +08:00
|
|
|
}
|
2010-09-27 22:49:38 +08:00
|
|
|
} while (1);
|
2011-02-15 07:40:20 +08:00
|
|
|
|
|
|
|
|
return 0;
|
2009-09-04 01:14:02 +08:00
|
|
|
}
|
2013-01-12 03:24:18 +08:00
|
|
|
omap_core_initcall(omap_serial_early_init);
|
2009-09-04 01:14:02 +08:00
|
|
|
|
2009-12-12 08:16:35 +08:00
|
|
|
/**
|
|
|
|
|
* omap_serial_init_port() - initialize single serial port
|
2010-12-23 10:42:35 +08:00
|
|
|
* @bdata: port specific board data pointer
|
2011-11-09 20:03:38 +08:00
|
|
|
* @info: platform specific data pointer
|
2009-12-12 08:16:35 +08:00
|
|
|
*
|
2010-12-23 10:42:35 +08:00
|
|
|
* This function initialies serial driver for given port only.
|
2009-12-12 08:16:35 +08:00
|
|
|
* Platforms can call this function instead of omap_serial_init()
|
|
|
|
|
* if they don't plan to use all available UARTs as serial ports.
|
|
|
|
|
*
|
|
|
|
|
* Don't mix calls to omap_serial_init_port() and omap_serial_init(),
|
|
|
|
|
* use only one of the two.
|
|
|
|
|
*/
|
2011-11-09 20:03:38 +08:00
|
|
|
void __init omap_serial_init_port(struct omap_board_data *bdata,
|
|
|
|
|
struct omap_uart_port_info *info)
|
2009-09-04 01:14:02 +08:00
|
|
|
{
|
2009-12-12 08:16:35 +08:00
|
|
|
struct omap_uart_state *uart;
|
2010-09-27 22:49:38 +08:00
|
|
|
struct omap_hwmod *oh;
|
2011-07-22 04:48:45 +08:00
|
|
|
struct platform_device *pdev;
|
2010-09-27 22:49:38 +08:00
|
|
|
void *pdata = NULL;
|
|
|
|
|
u32 pdata_size = 0;
|
|
|
|
|
char *name;
|
|
|
|
|
struct omap_uart_port_info omap_up;
|
2009-05-29 06:44:54 +08:00
|
|
|
|
2010-12-23 10:42:35 +08:00
|
|
|
if (WARN_ON(!bdata))
|
2010-09-27 22:49:38 +08:00
|
|
|
return;
|
2010-12-23 10:42:35 +08:00
|
|
|
if (WARN_ON(bdata->id < 0))
|
|
|
|
|
return;
|
|
|
|
|
if (WARN_ON(bdata->id >= num_uarts))
|
2010-02-28 04:13:43 +08:00
|
|
|
return;
|
2009-12-12 08:16:35 +08:00
|
|
|
|
2010-09-27 22:49:38 +08:00
|
|
|
list_for_each_entry(uart, &uart_list, node)
|
2010-12-23 10:42:35 +08:00
|
|
|
if (bdata->id == uart->num)
|
2010-09-27 22:49:38 +08:00
|
|
|
break;
|
2011-11-09 20:03:38 +08:00
|
|
|
if (!info)
|
|
|
|
|
info = omap_serial_default_info;
|
2009-12-14 21:59:18 +08:00
|
|
|
|
2010-09-27 22:49:38 +08:00
|
|
|
oh = uart->oh;
|
|
|
|
|
name = DRIVER_NAME;
|
|
|
|
|
|
2011-11-09 20:03:38 +08:00
|
|
|
omap_up.dma_enabled = info->dma_enabled;
|
2010-09-27 22:49:38 +08:00
|
|
|
omap_up.uartclk = OMAP24XX_BASE_BAUD * 16;
|
2011-09-13 16:31:01 +08:00
|
|
|
omap_up.flags = UPF_BOOT_AUTOCONF;
|
2011-10-11 21:41:27 +08:00
|
|
|
omap_up.get_context_loss_count = omap_pm_get_dev_context_loss_count;
|
2011-10-13 16:41:09 +08:00
|
|
|
omap_up.enable_wakeup = omap_uart_enable_wakeup;
|
2011-11-09 20:03:38 +08:00
|
|
|
omap_up.dma_rx_buf_size = info->dma_rx_buf_size;
|
|
|
|
|
omap_up.dma_rx_timeout = info->dma_rx_timeout;
|
2011-11-09 20:04:49 +08:00
|
|
|
omap_up.dma_rx_poll_rate = info->dma_rx_poll_rate;
|
2011-11-09 20:03:38 +08:00
|
|
|
omap_up.autosuspend_timeout = info->autosuspend_timeout;
|
2011-11-07 21:30:33 +08:00
|
|
|
|
2010-09-27 22:49:38 +08:00
|
|
|
pdata = &omap_up;
|
|
|
|
|
pdata_size = sizeof(struct omap_uart_port_info);
|
|
|
|
|
|
|
|
|
|
if (WARN_ON(!oh))
|
|
|
|
|
return;
|
|
|
|
|
|
2013-01-26 15:48:53 +08:00
|
|
|
pdev = omap_device_build(name, uart->num, oh, pdata, pdata_size);
|
2012-08-03 23:21:10 +08:00
|
|
|
if (IS_ERR(pdev)) {
|
|
|
|
|
WARN(1, "Could not build omap_device for %s: %s.\n", name,
|
|
|
|
|
oh->name);
|
|
|
|
|
return;
|
|
|
|
|
}
|
2010-09-27 22:49:38 +08:00
|
|
|
|
2010-12-23 10:42:35 +08:00
|
|
|
oh->mux = omap_hwmod_mux_init(bdata->pads, bdata->pads_cnt);
|
|
|
|
|
|
ARM: OMAP2: UART: fix console UART mismatched runtime PM status
The runtime PM framework assumes that the hardware state of devices
when initialized is disabled. For all omap_devices, we idle/disable
device by default. However, the console uart uses a "no idle" option
during omap_device init in order to allow earlyprintk usage to work
seamlessly during boot.
Because the hardware is left partially enabled after init (whatever
the bootloader settings were), the omap_device should later be fully
initialized (including mux) and the runtime PM framework should be
told that the device is active, and not disabled so that the hardware
state is in sync with runtime PM state.
To fix, after the device has been created/registered, call
omap_device_enable() to finialize init and use pm_runtime_set_active()
to tell the runtime PM core the device is enabled.
Tested on 2420/n810, 3530/Overo, 3530/Beagle, 3730/OveroSTORM,
3730/Beagle-xM, 4460/PandaES.
Suggested-by: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Sourav Poddar <sourav.poddar@ti.com>
Signed-off-by: Kevin Hilman <khilman@ti.com>
2012-10-16 06:19:34 +08:00
|
|
|
if (console_uart_id == bdata->id) {
|
|
|
|
|
omap_device_enable(pdev);
|
|
|
|
|
pm_runtime_set_active(&pdev->dev);
|
|
|
|
|
}
|
|
|
|
|
|
2010-09-27 22:49:38 +08:00
|
|
|
oh->dev_attr = uart;
|
|
|
|
|
|
2011-09-21 19:24:12 +08:00
|
|
|
if (((cpu_is_omap34xx() || cpu_is_omap44xx()) && bdata->pads)
|
|
|
|
|
&& !uart_debug)
|
2011-07-22 04:48:45 +08:00
|
|
|
device_init_wakeup(&pdev->dev, true);
|
2009-12-12 08:16:35 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/**
|
2011-11-09 20:03:38 +08:00
|
|
|
* omap_serial_board_init() - initialize all supported serial ports
|
|
|
|
|
* @info: platform specific data pointer
|
2009-12-12 08:16:35 +08:00
|
|
|
*
|
|
|
|
|
* Initializes all available UARTs as serial ports. Platforms
|
|
|
|
|
* can call this function when they want to have default behaviour
|
|
|
|
|
* for serial ports (e.g initialize them all as serial ports).
|
|
|
|
|
*/
|
2011-11-09 20:03:38 +08:00
|
|
|
void __init omap_serial_board_init(struct omap_uart_port_info *info)
|
2009-12-12 08:16:35 +08:00
|
|
|
{
|
2010-09-27 22:49:38 +08:00
|
|
|
struct omap_uart_state *uart;
|
2010-12-23 10:42:35 +08:00
|
|
|
struct omap_board_data bdata;
|
2009-12-12 08:16:35 +08:00
|
|
|
|
2010-12-23 10:42:35 +08:00
|
|
|
list_for_each_entry(uart, &uart_list, node) {
|
|
|
|
|
bdata.id = uart->num;
|
|
|
|
|
bdata.flags = 0;
|
|
|
|
|
bdata.pads = NULL;
|
|
|
|
|
bdata.pads_cnt = 0;
|
2011-11-07 21:25:05 +08:00
|
|
|
|
2012-06-05 19:04:11 +08:00
|
|
|
omap_serial_check_wakeup(&bdata, uart);
|
2011-11-07 21:25:05 +08:00
|
|
|
|
2011-11-09 20:03:38 +08:00
|
|
|
if (!info)
|
|
|
|
|
omap_serial_init_port(&bdata, NULL);
|
|
|
|
|
else
|
|
|
|
|
omap_serial_init_port(&bdata, &info[uart->num]);
|
2010-12-23 10:42:35 +08:00
|
|
|
}
|
2005-11-10 22:26:51 +08:00
|
|
|
}
|
2011-11-09 20:03:38 +08:00
|
|
|
|
|
|
|
|
/**
|
|
|
|
|
* omap_serial_init() - initialize all supported serial ports
|
|
|
|
|
*
|
|
|
|
|
* Initializes all available UARTs.
|
|
|
|
|
* Platforms can call this function when they want to have default behaviour
|
|
|
|
|
* for serial ports (e.g initialize them all as serial ports).
|
|
|
|
|
*/
|
|
|
|
|
void __init omap_serial_init(void)
|
|
|
|
|
{
|
|
|
|
|
omap_serial_board_init(NULL);
|
|
|
|
|
}
|