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-rw-r--r--arch/arm/mach-omap2/serial.c465
1 files changed, 428 insertions, 37 deletions
diff --git a/arch/arm/mach-omap2/serial.c b/arch/arm/mach-omap2/serial.c
index 4dcf39c285b9..b094c15bfe47 100644
--- a/arch/arm/mach-omap2/serial.c
+++ b/arch/arm/mach-omap2/serial.c
@@ -6,8 +6,13 @@
* 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.
@@ -21,9 +26,50 @@
#include <mach/common.h>
#include <mach/board.h>
+#include <mach/clock.h>
+#include <mach/control.h>
+
+#include "prm.h"
+#include "pm.h"
+#include "prm-regbits-34xx.h"
+
+#define UART_OMAP_WER 0x17 /* Wake-up enable register */
+
+#define DEFAULT_TIMEOUT (5 * HZ)
-static struct clk *uart_ick[OMAP_MAX_NR_PORTS];
-static struct clk *uart_fck[OMAP_MAX_NR_PORTS];
+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;
+
+#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 struct omap_uart_state omap_uart[OMAP_MAX_NR_PORTS];
+static LIST_HEAD(uart_list);
static struct plat_serial8250_port serial_platform_data[] = {
{
@@ -74,33 +120,369 @@ static inline void serial_write_reg(struct plat_serial8250_port *p, int offset,
* 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_serial_reset(struct plat_serial8250_port *p)
+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));
}
-void omap_serial_enable_clocks(int enable)
+#if defined(CONFIG_PM) && defined(CONFIG_ARCH_OMAP3)
+
+static int enable_off_mode; /* to be removed by full off-mode patches */
+
+static void omap_uart_save_context(struct omap_uart_state *uart)
{
- int i;
- for (i = 0; i < OMAP_MAX_NR_PORTS; i++) {
- if (uart_ick[i] && uart_fck[i]) {
- if (enable) {
- clk_enable(uart_ick[i]);
- clk_enable(uart_fck[i]);
- } else {
- clk_disable(uart_ick[i]);
- clk_disable(uart_fck[i]);
+ 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_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 (!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 u32 sleep_timeout = DEFAULT_TIMEOUT;
+
+static void omap_uart_idle_init(struct omap_uart_state *uart)
+{
+ u32 v;
+ struct plat_serial8250_port *p = uart->p;
+ int ret;
+
+ uart->can_sleep = 0;
+ uart->timeout = sleep_timeout;
+ setup_timer(&uart->timer, omap_uart_idle_timer,
+ (unsigned long) uart);
+ 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;
+ }
+
+ /* Set wake-enable bit */
+ if (uart->wk_en && uart->wk_mask) {
+ 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;
+
+ v = omap_ctrl_readw(uart->padconf);
+ v |= OMAP3_PADCONF_WAKEUPENABLE0;
+ omap_ctrl_writew(v, uart->padconf);
+ }
+
+ p->flags |= UPF_SHARE_IRQ;
+ ret = request_irq(p->irq, omap_uart_interrupt, IRQF_SHARED,
+ "serial idle", (void *)uart);
+ WARN_ON(ret);
+}
+
+static ssize_t sleep_timeout_show(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ char *buf)
+{
+ return sprintf(buf, "%u\n", sleep_timeout / HZ);
+}
+
+static ssize_t sleep_timeout_store(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ const char *buf, size_t n)
+{
+ struct omap_uart_state *uart;
+ unsigned int value;
+
+ if (sscanf(buf, "%u", &value) != 1) {
+ printk(KERN_ERR "sleep_timeout_store: Invalid value\n");
+ return -EINVAL;
+ }
+ sleep_timeout = value * HZ;
+ list_for_each_entry(uart, &uart_list, node) {
+ uart->timeout = sleep_timeout;
+ 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;
+}
+
+static struct kobj_attribute sleep_timeout_attr =
+ __ATTR(sleep_timeout, 0644, sleep_timeout_show, sleep_timeout_store);
+
+#else
+static inline void omap_uart_idle_init(struct omap_uart_state *uart) {}
+#endif /* CONFIG_PM */
+
+static struct platform_device serial_device = {
+ .name = "serial8250",
+ .id = PLAT8250_DEV_PLATFORM,
+ .dev = {
+ .platform_data = serial_platform_data,
+ },
+};
+
void __init omap_serial_init(void)
{
- int i;
+ int i, err;
const struct omap_uart_config *info;
char name[16];
@@ -114,9 +496,14 @@ void __init omap_serial_init(void)
if (info == NULL)
return;
+ if (cpu_is_omap44xx()) {
+ for (i = 0; i < OMAP_MAX_NR_PORTS; i++)
+ serial_platform_data[i].irq += 32;
+ }
for (i = 0; i < OMAP_MAX_NR_PORTS; i++) {
struct plat_serial8250_port *p = serial_platform_data + i;
+ struct omap_uart_state *uart = &omap_uart[i];
if (!(info->enabled_uarts & (1 << i))) {
p->membase = NULL;
@@ -125,35 +512,39 @@ void __init omap_serial_init(void)
}
sprintf(name, "uart%d_ick", i+1);
- uart_ick[i] = clk_get(NULL, name);
- if (IS_ERR(uart_ick[i])) {
+ 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[i] = NULL;
- } else
- clk_enable(uart_ick[i]);
+ uart->ick = NULL;
+ }
sprintf(name, "uart%d_fck", i+1);
- uart_fck[i] = clk_get(NULL, name);
- if (IS_ERR(uart_fck[i])) {
+ 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[i] = NULL;
- } else
- clk_enable(uart_fck[i]);
+ uart->fck = NULL;
+ }
- omap_serial_reset(p);
+ if (!uart->ick || !uart->fck)
+ continue;
+
+ uart->num = i;
+ p->private_data = uart;
+ uart->p = p;
+ list_add(&uart->node, &uart_list);
+
+ omap_uart_enable_clocks(uart);
+ omap_uart_reset(uart);
+ omap_uart_idle_init(uart);
}
-}
-static struct platform_device serial_device = {
- .name = "serial8250",
- .id = PLAT8250_DEV_PLATFORM,
- .dev = {
- .platform_data = serial_platform_data,
- },
-};
+ err = platform_device_register(&serial_device);
+
+#ifdef CONFIG_PM
+ if (!err)
+ err = sysfs_create_file(&serial_device.dev.kobj,
+ &sleep_timeout_attr.attr);
+#endif
-static int __init omap_init(void)
-{
- return platform_device_register(&serial_device);
}
-arch_initcall(omap_init);
+