3 files changed, 396 insertions, 25 deletions

diff --git a/arch/arm/mach-omap2/pm24xx.c b/arch/arm/mach-omap2/pm24xx.c
index d38f3121dde9..db1025562fb0 100644
--- a/arch/arm/mach-omap2/pm24xx.c
+++ b/arch/arm/mach-omap2/pm24xx.c
@@ -71,6 +71,11 @@ static int omap2_fclks_active(void)
 
 	f1 = cm_read_mod_reg(CORE_MOD, CM_FCLKEN1);
 	f2 = cm_read_mod_reg(CORE_MOD, OMAP24XX_CM_FCLKEN2);
+
+	/* Ignore UART clocks.  These are handled by UART core (serial.c) */
+	f1 &= ~(OMAP24XX_EN_UART1 | OMAP24XX_EN_UART2);
+	f2 &= ~OMAP24XX_EN_UART3;
+
 	if (f1 | f2)
 		return 1;
 	return 0;
@@ -117,12 +122,20 @@ static void omap2_enter_full_retention(void)
 	if (omap_irq_pending())
 		goto no_sleep;
 
+	omap_uart_prepare_idle(0);
+	omap_uart_prepare_idle(1);
+	omap_uart_prepare_idle(2);
+
 	/* Jump to SRAM suspend code */
 	omap2_sram_suspend(sdrc_read_reg(SDRC_DLLA_CTRL),
 			   OMAP_SDRC_REGADDR(SDRC_DLLA_CTRL),
 			   OMAP_SDRC_REGADDR(SDRC_POWER));
-no_sleep:
 
+	omap_uart_resume_idle(2);
+	omap_uart_resume_idle(1);
+	omap_uart_resume_idle(0);
+
+no_sleep:
 	if (omap2_pm_debug) {
 		unsigned long long tmp;
 
@@ -283,6 +296,7 @@ static int omap2_pm_suspend(void)
 	mir1 = omap_readl(0x480fe0a4);
 	omap_writel(1 << 5, 0x480fe0ac);
 
+	omap_uart_prepare_suspend();
 	omap2_enter_full_retention();
 
 	omap_writel(mir1, 0x480fe0a4);
diff --git a/arch/arm/mach-omap2/pm34xx.c b/arch/arm/mach-omap2/pm34xx.c
index b2a8730771e9..54876aca2d45 100644
--- a/arch/arm/mach-omap2/pm34xx.c
+++ b/arch/arm/mach-omap2/pm34xx.c
@@ -27,6 +27,7 @@
 #include <mach/clockdomain.h>
 #include <mach/powerdomain.h>
 #include <mach/control.h>
+#include <mach/serial.h>
 
 #include "cm.h"
 #include "cm-regbits-34xx.h"
@@ -168,10 +169,16 @@ static void omap_sram_idle(void)
 		return;
 	}
 	omap2_gpio_prepare_for_retention();
+	omap_uart_prepare_idle(0);
+	omap_uart_prepare_idle(1);
+	omap_uart_prepare_idle(2);
 
 	_omap_sram_idle(NULL, save_state);
 	cpu_init();
 
+	omap_uart_resume_idle(2);
+	omap_uart_resume_idle(1);
+	omap_uart_resume_idle(0);
 	omap2_gpio_resume_after_retention();
 }
 
@@ -204,6 +211,11 @@ static int omap3_fclks_active(void)
 				  CM_FCLKEN);
 	fck_per = cm_read_mod_reg(OMAP3430_PER_MOD,
 				  CM_FCLKEN);
+
+	/* Ignore UART clocks.  These are handled by UART core (serial.c) */
+	fck_core1 &= ~(OMAP3430_EN_UART1 | OMAP3430_EN_UART2);
+	fck_per &= ~OMAP3430_EN_UART3;
+
 	if (fck_core1 | fck_core3 | fck_sgx | fck_dss |
 	    fck_cam | fck_per | fck_usbhost)
 		return 1;
@@ -212,6 +224,8 @@ static int omap3_fclks_active(void)
 
 static int omap3_can_sleep(void)
 {
+	if (!omap_uart_can_sleep())
+		return 0;
 	if (omap3_fclks_active())
 		return 0;
 	return 1;
@@ -301,6 +315,7 @@ static int omap3_pm_suspend(void)
 			goto restore;
 	}
 
+	omap_uart_prepare_suspend();
 	omap_sram_idle();
 
 restore:
diff --git a/arch/arm/mach-omap2/serial.c b/arch/arm/mach-omap2/serial.c
index 4dcf39c285b9..53cbe0620286 100644
--- a/arch/arm/mach-omap2/serial.c
+++ b/arch/arm/mach-omap2/serial.c
@@ -6,6 +6,8 @@
  * 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
  *
  * This file is subject to the terms and conditions of the GNU General Public
@@ -21,9 +23,50 @@
 
 #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 (2 * HZ)
+
+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;
 
-static struct clk *uart_ick[OMAP_MAX_NR_PORTS];
-static struct clk *uart_fck[OMAP_MAX_NR_PORTS];
+#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[] = {
 	{
@@ -74,30 +117,320 @@ 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;
+	mod_timer(&uart->timer, jiffies + uart->timeout);
+}
+
+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 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 = DEFAULT_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);
+}
+
+#else
+static inline void omap_uart_idle_init(struct omap_uart_state *uart) {}
+#endif /* CONFIG_PM */
+
 void __init omap_serial_init(void)
 {
 	int i;
@@ -117,6 +450,7 @@ void __init omap_serial_init(void)
 
 	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;
@@ -125,22 +459,30 @@ 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;
+		}
+
+		if (!uart->ick || !uart->fck)
+			continue;
+
+		uart->num = i;
+		p->private_data = uart;
+		uart->p = p;
+		list_add(&uart->node, &uart_list);
 
-		omap_serial_reset(p);
+		omap_uart_enable_clocks(uart);
+		omap_uart_reset(uart);
+		omap_uart_idle_init(uart);
 	}
 }