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* Dynamic idle support for UART
@ 2008-05-29 14:55 Tero Kristo
  2008-05-29 14:55 ` [PATCH 1/1] Added sleep support to UART Tero Kristo
  0 siblings, 1 reply; 9+ messages in thread
From: Tero Kristo @ 2008-05-29 14:55 UTC (permalink / raw)
  To: linux-omap

This hack will most importantly allow serial console usage when dynamic
idle is enabled.

Note! Functionality under 24xx configuration has not been verified!
      There may be some problems with CONFIG_PM_DEBUG flag enabled,
      most likely during the PM debug information dumps after / before
      sleep. Without this debugging flag this patch should not affect 24xx
      devices. Todo: Someone to check functionality under 24xx
      configuration and to enable functionality by default on that
      platform also.



^ permalink raw reply	[flat|nested] 9+ messages in thread
* [PATCH 1/1] Added sleep support to UART
@ 2008-06-03 10:47 Tero Kristo
  2008-06-10  5:11 ` Tony Lindgren
  0 siblings, 1 reply; 9+ messages in thread
From: Tero Kristo @ 2008-06-03 10:47 UTC (permalink / raw)
  To: linux-omap

UART usage (e.g. serial console) now denies sleep for 5 seconds. This
makes it possible to use serial console when dynamic idle is enabled.

Also moved code from pm-debug.c to serial.c, and made pm24xx.c use this
new implementation.

Signed-off-by: Tero Kristo <tero.kristo@nokia.com>
---
 arch/arm/mach-omap2/pm-debug.c     |  132 ------------------------------------
 arch/arm/mach-omap2/pm.h           |    8 --
 arch/arm/mach-omap2/pm24xx.c       |   53 ++++++++++-----
 arch/arm/mach-omap2/pm34xx.c       |    5 ++
 arch/arm/mach-omap2/serial.c       |  118 ++++++++++++++++++++++++++++++++
 include/asm-arm/arch-omap/common.h |    3 +
 6 files changed, 162 insertions(+), 157 deletions(-)

diff --git a/arch/arm/mach-omap2/pm-debug.c b/arch/arm/mach-omap2/pm-debug.c
index 8a9f3c4..c20fa3b 100644
--- a/arch/arm/mach-omap2/pm-debug.c
+++ b/arch/arm/mach-omap2/pm-debug.c
@@ -34,138 +34,6 @@
 #ifdef CONFIG_PM_DEBUG
 int omap2_pm_debug = 0;
 
-static int serial_console_clock_disabled;
-static int serial_console_uart;
-static unsigned int serial_console_next_disable;
-
-static struct clk *console_iclk, *console_fclk;
-
-static void serial_console_kick(void)
-{
-	serial_console_next_disable = omap2_read_32k_sync_counter();
-	/* Keep the clocks on for 4 secs */
-	serial_console_next_disable += 4 * 32768;
-}
-
-static void serial_wait_tx(void)
-{
-	static const unsigned long uart_bases[3] = {
-		0x4806a000, 0x4806c000, 0x4806e000
-	};
-	unsigned long lsr_reg;
-	int looped = 0;
-
-	/* Wait for TX FIFO and THR to get empty */
-	lsr_reg = IO_ADDRESS(uart_bases[serial_console_uart - 1] + (5 << 2));
-	while ((__raw_readb(lsr_reg) & 0x60) != 0x60)
-		looped = 1;
-	if (looped)
-		serial_console_kick();
-}
-
-u32 omap2_read_32k_sync_counter(void)
-{
-        return omap_readl(OMAP2_32KSYNCT_BASE + 0x0010);
-}
-
-void serial_console_fclk_mask(u32 *f1, u32 *f2)
-{
-	switch (serial_console_uart)  {
-	case 1:
-		*f1 &= ~(1 << 21);
-		break;
-	case 2:
-		*f1 &= ~(1 << 22);
-		break;
-	case 3:
-		*f2 &= ~(1 << 2);
-		break;
-	}
-}
-
-void serial_console_sleep(int enable)
-{
-	if (console_iclk == NULL || console_fclk == NULL)
-		return;
-
-	if (enable) {
-		BUG_ON(serial_console_clock_disabled);
-		if (clk_get_usecount(console_fclk) == 0)
-			return;
-		if ((int) serial_console_next_disable - (int) omap2_read_32k_sync_counter() >= 0)
-			return;
-		serial_wait_tx();
-		clk_disable(console_iclk);
-		clk_disable(console_fclk);
-		serial_console_clock_disabled = 1;
-	} else {
-		int serial_wakeup = 0;
-		u32 l;
-
-		switch (serial_console_uart)  {
-		case 1:
-			l = prm_read_mod_reg(CORE_MOD, PM_WKST1);
-			if (l & OMAP24XX_ST_UART1)
-				serial_wakeup = 1;
-			break;
-		case 2:
-			l = prm_read_mod_reg(CORE_MOD, PM_WKST1);
-			if (l & OMAP24XX_ST_UART2)
-				serial_wakeup = 1;
-			break;
-		case 3:
-			l = prm_read_mod_reg(CORE_MOD, OMAP24XX_PM_WKST2);
-			if (l & OMAP24XX_ST_UART3)
-				serial_wakeup = 1;
-			break;
-		}
-		if (serial_wakeup)
-			serial_console_kick();
-		if (!serial_console_clock_disabled)
-			return;
-		clk_enable(console_iclk);
-		clk_enable(console_fclk);
-		serial_console_clock_disabled = 0;
-	}
-}
-
-void pm_init_serial_console(void)
-{
-	const struct omap_serial_console_config *conf;
-	char name[16];
-
-	conf = omap_get_config(OMAP_TAG_SERIAL_CONSOLE,
-			       struct omap_serial_console_config);
-	if (conf == NULL)
-		return;
-	if (conf->console_uart > 3 || conf->console_uart < 1)
-		return;
-	serial_console_uart = conf->console_uart;
-	sprintf(name, "uart%d_fck", conf->console_uart);
-	console_fclk = clk_get(NULL, name);
-	if (IS_ERR(console_fclk))
-		console_fclk = NULL;
-	name[6] = 'i';
-	console_iclk = clk_get(NULL, name);
-	if (IS_ERR(console_fclk))
-		console_iclk = NULL;
-	if (console_fclk == NULL || console_iclk == NULL) {
-		serial_console_uart = 0;
-		return;
-	}
-	switch (serial_console_uart) {
-	case 1:
-		prm_set_mod_reg_bits(OMAP24XX_ST_UART1, CORE_MOD, PM_WKEN1);
-		break;
-	case 2:
-		prm_set_mod_reg_bits(OMAP24XX_ST_UART2, CORE_MOD, PM_WKEN1);
-		break;
-	case 3:
-		prm_set_mod_reg_bits(OMAP24XX_ST_UART3, CORE_MOD, OMAP24XX_PM_WKEN2);
-		break;
-	}
-}
-
 #define DUMP_PRM_MOD_REG(mod, reg)    \
 	regs[reg_count].name = #mod "." #reg; \
 	regs[reg_count++].val = prm_read_mod_reg(mod, reg)
diff --git a/arch/arm/mach-omap2/pm.h b/arch/arm/mach-omap2/pm.h
index 351456e..a1a35ea 100644
--- a/arch/arm/mach-omap2/pm.h
+++ b/arch/arm/mach-omap2/pm.h
@@ -20,18 +20,10 @@ extern unsigned short enable_dyn_sleep;
 extern atomic_t sleep_block;
 
 #ifdef CONFIG_PM_DEBUG
-extern u32 omap2_read_32k_sync_counter(void);
 extern void omap2_pm_dump(int mode, int resume, unsigned int us);
-extern void serial_console_fclk_mask(u32 *f1, u32 *f2);
-extern void pm_init_serial_console(void);
-extern void serial_console_sleep(int enable);
 extern int omap2_pm_debug;
 #else
-#define omap2_read_32k_sync_counter() 0;
-#define serial_console_sleep(enable) do; while(0)
-#define pm_init_serial_console() do; while(0)
 #define omap2_pm_dump(mode,resume,us) do; while(0)
-#define serial_console_fclk_mask(f1,f2)  do; while(0)
 #define omap2_pm_debug 0
 #endif /* CONFIG_PM_DEBUG */
 #endif
diff --git a/arch/arm/mach-omap2/pm24xx.c b/arch/arm/mach-omap2/pm24xx.c
index bcf3afe..b65c0bb 100644
--- a/arch/arm/mach-omap2/pm24xx.c
+++ b/arch/arm/mach-omap2/pm24xx.c
@@ -44,6 +44,7 @@
 #include <asm/arch/mux.h>
 #include <asm/arch/dma.h>
 #include <asm/arch/board.h>
+#include <asm/arch/common.h>
 
 #include "prm.h"
 #include "prm-regbits-24xx.h"
@@ -73,7 +74,9 @@ 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);
-	serial_console_fclk_mask(&f1, &f2);
+#ifdef CONFIG_PM_DEBUG
+	omap_serial_fclk_mask(&f1, &f2);
+#endif
 	if (f1 | f2)
 		return 1;
 	return 0;
@@ -81,7 +84,8 @@ static int omap2_fclks_active(void)
 
 static void omap2_enter_full_retention(void)
 {
-	u32 l, sleep_time = 0;
+	u32 l = 0;
+	s64 sleep_time = 0;
 
 	/* There is 1 reference hold for all children of the oscillator
 	 * clock, the following will remove it. If no one else uses the
@@ -110,29 +114,38 @@ static void omap2_enter_full_retention(void)
 	omap2_gpio_prepare_for_retention();
 
 	if (omap2_pm_debug) {
+		struct timespec t;
 		omap2_pm_dump(0, 0, 0);
-		sleep_time = omap2_read_32k_sync_counter();
+		getnstimeofday(&t);
+		sleep_time = timespec_to_ns(&t);
 	}
 
+#ifdef CONFIG_PM_DEBUG
+	omap_serial_enable_clocks(0);
+#endif
+
 	/* One last check for pending IRQs to avoid extra latency due
 	 * to sleeping unnecessarily. */
 	if (omap_irq_pending())
 		goto no_sleep;
 
-	serial_console_sleep(1);
 	/* Jump to SRAM suspend code */
 	omap2_sram_suspend(OMAP_SDRC_REGADDR(SDRC_DLLA_CTRL));
 no_sleep:
-	serial_console_sleep(0);
+#ifdef CONFIG_PM_DEBUG
+	omap_serial_check_wakeup();
+	omap_serial_enable_clocks(1);
+#endif
 
 	if (omap2_pm_debug) {
 		unsigned long long tmp;
-		u32 resume_time;
+		s64 resume_time;
+		struct timespec t;
 
-		resume_time = omap2_read_32k_sync_counter();
+		getnstimeofday(&t);
+		resume_time = timespec_to_ns(&t);
 		tmp = resume_time - sleep_time;
-		tmp *= 1000000;
-		omap2_pm_dump(0, 1, tmp / 32768);
+		omap2_pm_dump(0, 1, tmp / 1000);
 	}
 	omap2_gpio_resume_after_retention();
 
@@ -193,7 +206,7 @@ static int omap2_allow_mpu_retention(void)
 
 static void omap2_enter_mpu_retention(void)
 {
-	u32 sleep_time = 0;
+	s64 sleep_time = 0;
 	int only_idle = 0;
 
 	/* Putting MPU into the WFI state while a transfer is active
@@ -221,20 +234,24 @@ static void omap2_enter_mpu_retention(void)
 	}
 
 	if (omap2_pm_debug) {
+		struct timespec t;
+
 		omap2_pm_dump(only_idle ? 2 : 1, 0, 0);
-		sleep_time = omap2_read_32k_sync_counter();
+		getnstimeofday(&t);
+		sleep_time = timespec_to_ns(&t);
 	}
 
 	omap2_sram_idle();
 
 	if (omap2_pm_debug) {
 		unsigned long long tmp;
-		u32 resume_time;
+		s64 resume_time;
+		struct timespec t;
 
-		resume_time = omap2_read_32k_sync_counter();
+		getnstimeofday(&t);
+		resume_time = timespec_to_ns(&t);
 		tmp = resume_time - sleep_time;
-		tmp *= 1000000;
-		omap2_pm_dump(only_idle ? 2 : 1, 1, tmp / 32768);
+		omap2_pm_dump(only_idle ? 2 : 1, 1, tmp / 1000);
 	}
 }
 
@@ -250,6 +267,10 @@ static int omap2_can_sleep(void)
 		return 0;
 	if (omap_dma_running())
 		return 0;
+#ifdef CONFIG_PM_DEBUG
+	if (!omap_serial_can_sleep())
+		return 0;
+#endif
 
 	return 1;
 }
@@ -517,8 +538,6 @@ int __init omap2_pm_init(void)
 
 	prcm_setup_regs();
 
-	pm_init_serial_console();
-
 	/* Hack to prevent MPU retention when STI console is enabled. */
 	{
 		const struct omap_sti_console_config *sti;
diff --git a/arch/arm/mach-omap2/pm34xx.c b/arch/arm/mach-omap2/pm34xx.c
index 7e775cc..b047d47 100644
--- a/arch/arm/mach-omap2/pm34xx.c
+++ b/arch/arm/mach-omap2/pm34xx.c
@@ -58,6 +58,9 @@ static irqreturn_t prcm_interrupt_handler (int irq, void *dev_id)
 	u32 wkst, irqstatus_mpu;
 	u32 fclk, iclk;
 
+	/* Check if we woke up to serial console activity */
+	omap_serial_check_wakeup();
+
 	/* WKUP */
 	wkst = prm_read_mod_reg(WKUP_MOD, PM_WKST);
 	if (wkst) {
@@ -176,6 +179,8 @@ static int omap3_can_sleep(void)
 		return 0;
 	if (atomic_read(&sleep_block) > 0)
 		return 0;
+	if (!omap_serial_can_sleep())
+		return 0;
 	return 1;
 }
 
diff --git a/arch/arm/mach-omap2/serial.c b/arch/arm/mach-omap2/serial.c
index b0fa582..65571f9 100644
--- a/arch/arm/mach-omap2/serial.c
+++ b/arch/arm/mach-omap2/serial.c
@@ -23,8 +23,47 @@
 #include <asm/arch/common.h>
 #include <asm/arch/board.h>
 
+#include "prm.h"
+#include "pm.h"
+
+#define SERIAL_AWAKE_TIME 5
+
 static struct clk *uart_ick[OMAP_MAX_NR_PORTS];
 static struct clk *uart_fck[OMAP_MAX_NR_PORTS];
+static s64 omap_serial_next_sleep;
+
+static const u32 omap2_uart_wk_st[OMAP_MAX_NR_PORTS] = {
+	PM_WKST1, PM_WKST1, OMAP24XX_PM_WKST2
+};
+static const u32 omap2_uart_wk_en[OMAP_MAX_NR_PORTS] = {
+	PM_WKEN1, PM_WKEN1, OMAP24XX_PM_WKEN2
+};
+const u32 omap2_uart_wk_bit[OMAP_MAX_NR_PORTS] = {
+	OMAP24XX_ST_UART1, OMAP24XX_ST_UART2, OMAP24XX_ST_UART3
+};
+
+#if defined(CONFIG_ARCH_OMAP2)
+static const u32 omap_uart_fclk_mask[OMAP_MAX_NR_PORTS] = {
+	OMAP24XX_EN_UART1, OMAP24XX_EN_UART2, OMAP24XX_EN_UART3
+};
+#endif
+
+#if defined(CONFIG_ARCH_OMAP3)
+static const u32 omap_uart_fclk_mask[OMAP_MAX_NR_PORTS] = {
+	OMAP3430_EN_UART1, OMAP3430_EN_UART2, OMAP3430_EN_UART3
+};
+
+/* UART padconfig registers, these may differ if non-default padconfig
+   is used */
+#define CONTROL_PADCONF_UART1_RX 0x48002182
+#define CONTROL_PADCONF_UART2_RX 0x4800217A
+#define CONTROL_PADCONF_UART3_RX 0x4800219E
+#define PADCONF_WAKEUP_ST 0x8000
+
+static const u32 omap_uart_padconf[OMAP_MAX_NR_PORTS] = {
+	CONTROL_PADCONF_UART1_RX, CONTROL_PADCONF_UART2_RX, CONTROL_PADCONF_UART3_RX
+};
+#endif
 
 static struct plat_serial8250_port serial_platform_data[] = {
 	{
@@ -83,6 +122,15 @@ static inline void __init omap_serial_reset(struct plat_serial8250_port *p)
 	serial_write_reg(p, UART_OMAP_SYSC, (0x02 << 3) | (1 << 2) | (1 << 0));
 }
 
+static void omap_serial_kick(void)
+{
+	struct timespec t;
+
+	getnstimeofday(&t);
+	omap_serial_next_sleep = timespec_to_ns(&t) +
+		(s64)SERIAL_AWAKE_TIME * (s64)1000000000;
+}
+
 void omap_serial_enable_clocks(int enable)
 {
 	int i;
@@ -99,6 +147,71 @@ void omap_serial_enable_clocks(int enable)
 	}
 }
 
+void omap_serial_fclk_mask(u32 *f1, u32 *f2)
+{
+	if (uart_ick[0])
+		*f1 &= ~omap_uart_fclk_mask[0];
+	if (uart_ick[1])
+		*f1 &= ~omap_uart_fclk_mask[1];
+	if (uart_ick[2])
+		*f2 &= ~omap_uart_fclk_mask[2];
+}
+
+void omap_serial_check_wakeup(void)
+{
+	int i;
+
+	if (cpu_is_omap34xx())
+		for (i = 0; i < OMAP_MAX_NR_PORTS; i++) {
+			if (!uart_ick[i])
+				continue;
+			if (omap_readw(omap_uart_padconf[i]) & PADCONF_WAKEUP_ST)
+				omap_serial_kick();
+				return;
+		}
+
+	if (cpu_is_omap24xx()) {
+		u32 l;
+
+		for (i = 0; i < OMAP_MAX_NR_PORTS; i++) {
+			if (!uart_ick[i])
+				continue;
+			l = prm_read_mod_reg(CORE_MOD, omap2_uart_wk_st[i]);
+			if (l & omap2_uart_wk_bit[i])
+				omap_serial_kick();
+				return;
+		}
+	}
+}
+
+int omap_serial_can_sleep(void)
+{
+	s64 cnt;
+	int i;
+	struct timespec t;
+
+	struct plat_serial8250_port *p = serial_platform_data;
+
+	getnstimeofday(&t);
+	cnt = timespec_to_ns(&t);
+
+	for (i = 0; i < OMAP_MAX_NR_PORTS; i++) {
+		if (!uart_ick[i])
+			continue;
+		/* Check if we have data in the transmit buffer */
+		if ((serial_read_reg(p + i, UART_LSR) & (UART_LSR_TEMT|UART_LSR_THRE))
+			!= (UART_LSR_TEMT|UART_LSR_THRE)) {
+				omap_serial_kick();
+				return 0;
+		}
+	}
+
+	if (omap_serial_next_sleep - cnt >= 0)
+		return 0;
+
+	return 1;
+}
+
 void __init omap_serial_init(void)
 {
 	int i;
@@ -142,7 +255,12 @@ void __init omap_serial_init(void)
 			clk_enable(uart_fck[i]);
 
 		omap_serial_reset(p);
+
+		if (cpu_is_omap24xx())
+			prm_set_mod_reg_bits(omap2_uart_wk_bit[i], CORE_MOD, omap2_uart_wk_en[i]);
 	}
+
+	omap_serial_kick();
 }
 
 static struct platform_device serial_device = {
diff --git a/include/asm-arm/arch-omap/common.h b/include/asm-arm/arch-omap/common.h
index 7a48fc9..5d2033b 100644
--- a/include/asm-arm/arch-omap/common.h
+++ b/include/asm-arm/arch-omap/common.h
@@ -35,6 +35,9 @@ extern void omap_map_common_io(void);
 extern struct sys_timer omap_timer;
 extern void omap_serial_init(void);
 extern void omap_serial_enable_clocks(int enable);
+extern int omap_serial_can_sleep(void);
+extern void omap_serial_fclk_mask(u32 *f1, u32 *f2);
+void omap_serial_check_wakeup(void);
 #ifdef CONFIG_I2C_OMAP
 extern int omap_register_i2c_bus(int bus_id, u32 clkrate,
 				 struct i2c_board_info const *info,
-- 
1.5.4.3


^ permalink raw reply related	[flat|nested] 9+ messages in thread
end of thread, other threads:[~2008-06-10 14:09 UTC | newest]

Thread overview: 9+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2008-05-29 14:55 Dynamic idle support for UART Tero Kristo
2008-05-29 14:55 ` [PATCH 1/1] Added sleep support to UART Tero Kristo
2008-05-30 23:01   ` Tony Lindgren
2008-06-02  8:09     ` Tero.Kristo
2008-06-02 16:29       ` Tony Lindgren
  -- strict thread matches above, loose matches on Subject: below --
2008-06-03 10:47 Tero Kristo
2008-06-10  5:11 ` Tony Lindgren
2008-06-10  6:06   ` Tony Lindgren
2008-06-10 14:07     ` Tero.Kristo

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