UbiquitousOS
/
OpenCloudOS-Kernel
mirror of https://gitee.com/OpenCloudOS/OpenCloudOS-Kernel.git
11
0
Fork 0
Code Issues Projects Releases Wiki Activity
OpenCloudOS-Kernel/arch/arm/mach-omap2/serial.c

780 lines
18 KiB
C
Raw Blame History

/*
* arch/arm/mach-omap2/serial.c
*
* OMAP2 serial support.
*
* Copyright (C) 2005-2008 Nokia Corporation
* Author: Paul Mundt <paul.mundt@nokia.com>
*
* Major rework for PM support by Kevin Hilman
*
* Based off of arch/arm/mach-omap/omap1/serial.c
*
* Copyright (C) 2009 Texas Instruments
* Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com
*
* 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>
#include <linux/serial_8250.h>
#include <linux/serial_reg.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/delay.h>
#include <plat/common.h>
#include <plat/board.h>
#include <plat/clock.h>
#include <plat/control.h>
#include "prm.h"
#include "pm.h"
#include "prm-regbits-34xx.h"
#define UART_OMAP_NO_EMPTY_FIFO_READ_IP_REV 0x52
#define UART_OMAP_WER 0x17 /* Wake-up enable register */
/*
* NOTE: By default the serial timeout is disabled as it causes lost characters
* over the serial ports. This means that the UART clocks will stay on until
* disabled via sysfs. This also causes that any deeper omap sleep states are
* blocked.
*/
#define DEFAULT_TIMEOUT 0
struct omap_uart_state {
int num;
int can_sleep;
struct timer_list timer;
u32 timeout;
void __iomem *wk_st;
void __iomem *wk_en;
u32 wk_mask;
u32 padconf;
struct clk *ick;
struct clk *fck;
int clocked;
struct plat_serial8250_port *p;
struct list_head node;
struct platform_device pdev;
#if defined(CONFIG_ARCH_OMAP3) && defined(CONFIG_PM)
int context_valid;
/* Registers to be saved/restored for OFF-mode */
u16 dll;
u16 dlh;
u16 ier;
u16 sysc;
u16 scr;
u16 wer;
#endif
};
static LIST_HEAD(uart_list);
static struct plat_serial8250_port serial_platform_data0[] = {
{
.irq = 72,
.flags = UPF_BOOT_AUTOCONF,
.iotype = UPIO_MEM,
.regshift = 2,
.uartclk = OMAP24XX_BASE_BAUD * 16,
}, {
.flags = 0
}
};
static struct plat_serial8250_port serial_platform_data1[] = {
{
.irq = 73,
.flags = UPF_BOOT_AUTOCONF,
.iotype = UPIO_MEM,
.regshift = 2,
.uartclk = OMAP24XX_BASE_BAUD * 16,
}, {
.flags = 0
}
};
static struct plat_serial8250_port serial_platform_data2[] = {
{
.irq = 74,
.flags = UPF_BOOT_AUTOCONF,
.iotype = UPIO_MEM,
.regshift = 2,
.uartclk = OMAP24XX_BASE_BAUD * 16,
}, {
.flags = 0
}
};
#if defined(CONFIG_ARCH_OMAP3) || defined(CONFIG_ARCH_OMAP4)
static struct plat_serial8250_port serial_platform_data3[] = {
{
.irq = 70,
.flags = UPF_BOOT_AUTOCONF,
.iotype = UPIO_MEM,
.regshift = 2,
.uartclk = OMAP24XX_BASE_BAUD * 16,
}, {
.flags = 0
}
};
static inline void omap2_set_globals_uart4(struct omap_globals *omap2_globals)
{
serial_platform_data3[0].mapbase = omap2_globals->uart4_phys;
}
#else
static inline void omap2_set_globals_uart4(struct omap_globals *omap2_globals)
{
}
#endif
void __init omap2_set_globals_uart(struct omap_globals *omap2_globals)
{
serial_platform_data0[0].mapbase = omap2_globals->uart1_phys;
serial_platform_data1[0].mapbase = omap2_globals->uart2_phys;
serial_platform_data2[0].mapbase = omap2_globals->uart3_phys;
if (cpu_is_omap3630() || cpu_is_omap44xx())
omap2_set_globals_uart4(omap2_globals);
}
static inline unsigned int __serial_read_reg(struct uart_port *up,
int offset)
{
offset <<= up->regshift;
return (unsigned int)__raw_readb(up->membase + offset);
}
static inline unsigned int serial_read_reg(struct plat_serial8250_port *up,
int offset)
{
offset <<= up->regshift;
return (unsigned int)__raw_readb(up->membase + offset);
}
static inline void __serial_write_reg(struct uart_port *up, int offset,
int value)
{
offset <<= up->regshift;
__raw_writeb(value, up->membase + offset);
}
static inline void serial_write_reg(struct plat_serial8250_port *p, int offset,
int value)
{
offset <<= p->regshift;
__raw_writeb(value, p->membase + offset);
}
/*
* Internal UARTs need to be initialized for the 8250 autoconfig to work
* properly. Note that the TX watermark initialization may not be needed
* once the 8250.c watermark handling code is merged.
*/
static inline void __init omap_uart_reset(struct omap_uart_state *uart)
{
struct plat_serial8250_port *p = uart->p;
serial_write_reg(p, UART_OMAP_MDR1, 0x07);
serial_write_reg(p, UART_OMAP_SCR, 0x08);
serial_write_reg(p, UART_OMAP_MDR1, 0x00);
serial_write_reg(p, UART_OMAP_SYSC, (0x02 << 3) | (1 << 2) | (1 << 0));
}
#if defined(CONFIG_PM) && defined(CONFIG_ARCH_OMAP3)
static void omap_uart_save_context(struct omap_uart_state *uart)
{
u16 lcr = 0;
struct plat_serial8250_port *p = uart->p;
if (!enable_off_mode)
return;
lcr = serial_read_reg(p, UART_LCR);
serial_write_reg(p, UART_LCR, 0xBF);
uart->dll = serial_read_reg(p, UART_DLL);
uart->dlh = serial_read_reg(p, UART_DLM);
serial_write_reg(p, UART_LCR, lcr);
uart->ier = serial_read_reg(p, UART_IER);
uart->sysc = serial_read_reg(p, UART_OMAP_SYSC);
uart->scr = serial_read_reg(p, UART_OMAP_SCR);
uart->wer = serial_read_reg(p, UART_OMAP_WER);
uart->context_valid = 1;
}
static void omap_uart_restore_context(struct omap_uart_state *uart)
{
u16 efr = 0;
struct plat_serial8250_port *p = uart->p;
if (!enable_off_mode)
return;
if (!uart->context_valid)
return;
uart->context_valid = 0;
serial_write_reg(p, UART_OMAP_MDR1, 0x7);
serial_write_reg(p, UART_LCR, 0xBF); /* Config B mode */
efr = serial_read_reg(p, UART_EFR);
serial_write_reg(p, UART_EFR, UART_EFR_ECB);
serial_write_reg(p, UART_LCR, 0x0); /* Operational mode */
serial_write_reg(p, UART_IER, 0x0);
serial_write_reg(p, UART_LCR, 0xBF); /* Config B mode */
serial_write_reg(p, UART_DLL, uart->dll);
serial_write_reg(p, UART_DLM, uart->dlh);
serial_write_reg(p, UART_LCR, 0x0); /* Operational mode */
serial_write_reg(p, UART_IER, uart->ier);
serial_write_reg(p, UART_FCR, 0xA1);
serial_write_reg(p, UART_LCR, 0xBF); /* Config B mode */
serial_write_reg(p, UART_EFR, efr);
serial_write_reg(p, UART_LCR, UART_LCR_WLEN8);
serial_write_reg(p, UART_OMAP_SCR, uart->scr);
serial_write_reg(p, UART_OMAP_WER, uart->wer);
serial_write_reg(p, UART_OMAP_SYSC, uart->sysc);
serial_write_reg(p, UART_OMAP_MDR1, 0x00); /* UART 16x mode */
}
#else
static inline void omap_uart_save_context(struct omap_uart_state *uart) {}
static inline void omap_uart_restore_context(struct omap_uart_state *uart) {}
#endif /* CONFIG_PM && CONFIG_ARCH_OMAP3 */
static inline void omap_uart_enable_clocks(struct omap_uart_state *uart)
{
if (uart->clocked)
return;
clk_enable(uart->ick);
clk_enable(uart->fck);
uart->clocked = 1;
omap_uart_restore_context(uart);
}
#ifdef CONFIG_PM
static inline void omap_uart_disable_clocks(struct omap_uart_state *uart)
{
if (!uart->clocked)
return;
omap_uart_save_context(uart);
uart->clocked = 0;
clk_disable(uart->ick);
clk_disable(uart->fck);
}
static void omap_uart_enable_wakeup(struct omap_uart_state *uart)
{
/* Set wake-enable bit */
if (uart->wk_en && uart->wk_mask) {
u32 v = __raw_readl(uart->wk_en);
v |= uart->wk_mask;
__raw_writel(v, uart->wk_en);
}
/* Ensure IOPAD wake-enables are set */
if (cpu_is_omap34xx() && uart->padconf) {
u16 v = omap_ctrl_readw(uart->padconf);
v |= OMAP3_PADCONF_WAKEUPENABLE0;
omap_ctrl_writew(v, uart->padconf);
}
}
static void omap_uart_disable_wakeup(struct omap_uart_state *uart)
{
/* Clear wake-enable bit */
if (uart->wk_en && uart->wk_mask) {
u32 v = __raw_readl(uart->wk_en);
v &= ~uart->wk_mask;
__raw_writel(v, uart->wk_en);
}
/* Ensure IOPAD wake-enables are cleared */
if (cpu_is_omap34xx() && uart->padconf) {
u16 v = omap_ctrl_readw(uart->padconf);
v &= ~OMAP3_PADCONF_WAKEUPENABLE0;
omap_ctrl_writew(v, uart->padconf);
}
}
static void omap_uart_smart_idle_enable(struct omap_uart_state *uart,
int enable)
{
struct plat_serial8250_port *p = uart->p;
u16 sysc;
sysc = serial_read_reg(p, UART_OMAP_SYSC) & 0x7;
if (enable)
sysc |= 0x2 << 3;
else
sysc |= 0x1 << 3;
serial_write_reg(p, UART_OMAP_SYSC, sysc);
}
static void omap_uart_block_sleep(struct omap_uart_state *uart)
{
omap_uart_enable_clocks(uart);
omap_uart_smart_idle_enable(uart, 0);
uart->can_sleep = 0;
if (uart->timeout)
mod_timer(&uart->timer, jiffies + uart->timeout);
else
del_timer(&uart->timer);
}
static void omap_uart_allow_sleep(struct omap_uart_state *uart)
{
if (device_may_wakeup(&uart->pdev.dev))
omap_uart_enable_wakeup(uart);
else
omap_uart_disable_wakeup(uart);
if (!uart->clocked)
return;
omap_uart_smart_idle_enable(uart, 1);
uart->can_sleep = 1;
del_timer(&uart->timer);
}
static void omap_uart_idle_timer(unsigned long data)
{
struct omap_uart_state *uart = (struct omap_uart_state *)data;
omap_uart_allow_sleep(uart);
}
void omap_uart_prepare_idle(int num)
{
struct omap_uart_state *uart;
list_for_each_entry(uart, &uart_list, node) {
if (num == uart->num && uart->can_sleep) {
omap_uart_disable_clocks(uart);
return;
}
}
}
void omap_uart_resume_idle(int num)
{
struct omap_uart_state *uart;
list_for_each_entry(uart, &uart_list, node) {
if (num == uart->num) {
omap_uart_enable_clocks(uart);
/* Check for IO pad wakeup */
if (cpu_is_omap34xx() && uart->padconf) {
u16 p = omap_ctrl_readw(uart->padconf);
if (p & OMAP3_PADCONF_WAKEUPEVENT0)
omap_uart_block_sleep(uart);
}
/* Check for normal UART wakeup */
if (__raw_readl(uart->wk_st) & uart->wk_mask)
omap_uart_block_sleep(uart);
return;
}
}
}
void omap_uart_prepare_suspend(void)
{
struct omap_uart_state *uart;
list_for_each_entry(uart, &uart_list, node) {
omap_uart_allow_sleep(uart);
}
}
int omap_uart_can_sleep(void)
{
struct omap_uart_state *uart;
int can_sleep = 1;
list_for_each_entry(uart, &uart_list, node) {
if (!uart->clocked)
continue;
if (!uart->can_sleep) {
can_sleep = 0;
continue;
}
/* This UART can now safely sleep. */
omap_uart_allow_sleep(uart);
}
return can_sleep;
}
/**
* omap_uart_interrupt()
*
* This handler is used only to detect that *any* UART interrupt has
* occurred. It does _nothing_ to handle the interrupt. Rather,
* any UART interrupt will trigger the inactivity timer so the
* UART will not idle or sleep for its timeout period.
*
**/
static irqreturn_t omap_uart_interrupt(int irq, void *dev_id)
{
struct omap_uart_state *uart = dev_id;
omap_uart_block_sleep(uart);
return IRQ_NONE;
}
static void omap_uart_idle_init(struct omap_uart_state *uart)
{
struct plat_serial8250_port *p = uart->p;
int ret;
uart->can_sleep = 0;
uart->timeout = DEFAULT_TIMEOUT;
setup_timer(&uart->timer, omap_uart_idle_timer,
(unsigned long) uart);
if (uart->timeout)
mod_timer(&uart->timer, jiffies + uart->timeout);
omap_uart_smart_idle_enable(uart, 0);
if (cpu_is_omap34xx()) {
u32 mod = (uart->num == 2) ? OMAP3430_PER_MOD : CORE_MOD;
u32 wk_mask = 0;
u32 padconf = 0;
uart->wk_en = OMAP34XX_PRM_REGADDR(mod, PM_WKEN1);
uart->wk_st = OMAP34XX_PRM_REGADDR(mod, PM_WKST1);
switch (uart->num) {
case 0:
wk_mask = OMAP3430_ST_UART1_MASK;
padconf = 0x182;
break;
case 1:
wk_mask = OMAP3430_ST_UART2_MASK;
padconf = 0x17a;
break;
case 2:
wk_mask = OMAP3430_ST_UART3_MASK;
padconf = 0x19e;
break;
}
uart->wk_mask = wk_mask;
uart->padconf = padconf;
} else if (cpu_is_omap24xx()) {
u32 wk_mask = 0;
if (cpu_is_omap2430()) {
uart->wk_en = OMAP2430_PRM_REGADDR(CORE_MOD, PM_WKEN1);
uart->wk_st = OMAP2430_PRM_REGADDR(CORE_MOD, PM_WKST1);
} else if (cpu_is_omap2420()) {
uart->wk_en = OMAP2420_PRM_REGADDR(CORE_MOD, PM_WKEN1);
uart->wk_st = OMAP2420_PRM_REGADDR(CORE_MOD, PM_WKST1);
}
switch (uart->num) {
case 0:
wk_mask = OMAP24XX_ST_UART1_MASK;
break;
case 1:
wk_mask = OMAP24XX_ST_UART2_MASK;
break;
case 2:
wk_mask = OMAP24XX_ST_UART3_MASK;
break;
}
uart->wk_mask = wk_mask;
} else {
uart->wk_en = 0;
uart->wk_st = 0;
uart->wk_mask = 0;
uart->padconf = 0;
}
p->irqflags |= IRQF_SHARED;
ret = request_irq(p->irq, omap_uart_interrupt, IRQF_SHARED,
"serial idle", (void *)uart);
WARN_ON(ret);
}
void omap_uart_enable_irqs(int enable)
{
int ret;
struct omap_uart_state *uart;
list_for_each_entry(uart, &uart_list, node) {
if (enable)
ret = request_irq(uart->p->irq, omap_uart_interrupt,
IRQF_SHARED, "serial idle", (void *)uart);
else
free_irq(uart->p->irq, (void *)uart);
}
}
static ssize_t sleep_timeout_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct platform_device *pdev = container_of(dev,
struct platform_device, dev);
struct omap_uart_state *uart = container_of(pdev,
struct omap_uart_state, pdev);
return sprintf(buf, "%u\n", uart->timeout / HZ);
}
static ssize_t sleep_timeout_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t n)
{
struct platform_device *pdev = container_of(dev,
struct platform_device, dev);
struct omap_uart_state *uart = container_of(pdev,
struct omap_uart_state, pdev);
unsigned int value;
if (sscanf(buf, "%u", &value) != 1) {
printk(KERN_ERR "sleep_timeout_store: Invalid value\n");
return -EINVAL;
}
uart->timeout = value * HZ;
if (uart->timeout)
mod_timer(&uart->timer, jiffies + uart->timeout);
else
/* A zero value means disable timeout feature */
omap_uart_block_sleep(uart);
return n;
}
DEVICE_ATTR(sleep_timeout, 0644, sleep_timeout_show, sleep_timeout_store);
#define DEV_CREATE_FILE(dev, attr) WARN_ON(device_create_file(dev, attr))
#else
static inline void omap_uart_idle_init(struct omap_uart_state *uart) {}
#define DEV_CREATE_FILE(dev, attr)
#endif /* CONFIG_PM */
static struct omap_uart_state omap_uart[] = {
{
.pdev = {
.name = "serial8250",
.id = PLAT8250_DEV_PLATFORM,
.dev = {
.platform_data = serial_platform_data0,
},
},
}, {
.pdev = {
.name = "serial8250",
.id = PLAT8250_DEV_PLATFORM1,
.dev = {
.platform_data = serial_platform_data1,
},
},
}, {
.pdev = {
.name = "serial8250",
.id = PLAT8250_DEV_PLATFORM2,
.dev = {
.platform_data = serial_platform_data2,
},
},
},
#if defined(CONFIG_ARCH_OMAP3) || defined(CONFIG_ARCH_OMAP4)
{
.pdev = {
.name = "serial8250",
.id = 3,
.dev = {
.platform_data = serial_platform_data3,
},
},
},
#endif
};
/*
* Override the default 8250 read handler: mem_serial_in()
* Empty RX fifo read causes an abort on omap3630 and omap4
* This function makes sure that an empty rx fifo is not read on these silicons
* (OMAP1/2/3430 are not affected)
*/
static unsigned int serial_in_override(struct uart_port *up, int offset)
{
if (UART_RX == offset) {
unsigned int lsr;
lsr = __serial_read_reg(up, UART_LSR);
if (!(lsr & UART_LSR_DR))
return -EPERM;
}
return __serial_read_reg(up, offset);
}
static void serial_out_override(struct uart_port *up, int offset, int value)
{
unsigned int status, tmout = 10000;
status = __serial_read_reg(up, UART_LSR);
while (!(status & UART_LSR_THRE)) {
/* Wait up to 10ms for the character(s) to be sent. */
if (--tmout == 0)
break;
udelay(1);
status = __serial_read_reg(up, UART_LSR);
}
__serial_write_reg(up, offset, value);
}
void __init omap_serial_early_init(void)
{
int i, nr_ports;
char name[16];
if (!(cpu_is_omap3630() || cpu_is_omap4430()))
nr_ports = 3;
else
nr_ports = ARRAY_SIZE(omap_uart);
/*
* Make sure the serial ports are muxed on at this point.
* You have to mux them off in device drivers later on
* if not needed.
*/
for (i = 0; i < nr_ports; i++) {
struct omap_uart_state *uart = &omap_uart[i];
struct platform_device *pdev = &uart->pdev;
struct device *dev = &pdev->dev;
struct plat_serial8250_port *p = dev->platform_data;
/*
* Module 4KB + L4 interconnect 4KB
* Static mapping, never released
*/
p->membase = ioremap(p->mapbase, SZ_8K);
if (!p->membase) {
printk(KERN_ERR "ioremap failed for uart%i\n", i + 1);
continue;
}
sprintf(name, "uart%d_ick", i + 1);
uart->ick = clk_get(NULL, name);
if (IS_ERR(uart->ick)) {
printk(KERN_ERR "Could not get uart%d_ick\n", i + 1);
uart->ick = NULL;
}
sprintf(name, "uart%d_fck", i+1);
uart->fck = clk_get(NULL, name);
if (IS_ERR(uart->fck)) {
printk(KERN_ERR "Could not get uart%d_fck\n", i + 1);
uart->fck = NULL;
}
/* FIXME: Remove this once the clkdev is ready */
if (!cpu_is_omap44xx()) {
if (!uart->ick || !uart->fck)
continue;
}
uart->num = i;
p->private_data = uart;
uart->p = p;
if (cpu_is_omap44xx())
p->irq += 32;
}
}
/**
* omap_serial_init_port() - initialize single serial port
* @port: serial port number (0-3)
*
* This function initialies serial driver for given @port only.
* 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.
*/
void __init omap_serial_init_port(int port)
{
struct omap_uart_state *uart;
struct platform_device *pdev;
struct device *dev;
BUG_ON(port < 0);
BUG_ON(port >= ARRAY_SIZE(omap_uart));
uart = &omap_uart[port];
pdev = &uart->pdev;
dev = &pdev->dev;
omap_uart_enable_clocks(uart);
omap_uart_reset(uart);
omap_uart_idle_init(uart);
list_add_tail(&uart->node, &uart_list);
if (WARN_ON(platform_device_register(pdev)))
return;
if ((cpu_is_omap34xx() && uart->padconf) ||
(uart->wk_en && uart->wk_mask)) {
device_init_wakeup(dev, true);
DEV_CREATE_FILE(dev, &dev_attr_sleep_timeout);
}
/*
* omap44xx: Never read empty UART fifo
* omap3xxx: Never read empty UART fifo on UARTs
* with IP rev >=0x52
*/
if (cpu_is_omap44xx()) {
uart->p->serial_in = serial_in_override;
uart->p->serial_out = serial_out_override;
} else if ((serial_read_reg(uart->p, UART_OMAP_MVER) & 0xFF)
>= UART_OMAP_NO_EMPTY_FIFO_READ_IP_REV) {
uart->p->serial_in = serial_in_override;
uart->p->serial_out = serial_out_override;
}
}
/**
* omap_serial_init() - intialize all supported serial ports
*
* 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).
*/
void __init omap_serial_init(void)
{
int i, nr_ports;
if (!(cpu_is_omap3630() || cpu_is_omap4430()))
nr_ports = 3;
else
nr_ports = ARRAY_SIZE(omap_uart);
for (i = 0; i < nr_ports; i++)
omap_serial_init_port(i);
}
Reference in New Issue View Git Blame Copy Permalink