ARM: S3C64XX: Implement basic power domain support

The S3C64xx SoCs contain a set of gateable power domains which can be
enabled and disabled at runtime in order to save power.  Use the generic
power domain code to implement support for these in software, enabling
runtime control of most domains:

 - ETM (not supported in mainline).
 - Domain G: 3D acceleration (no mainline support).
 - Domain V: MFC (no mainline support).
 - Domain I: JPEG and camera interface (no mainline support).
 - Domain P: 2D acceleration, TV encoder and scaler (no mainline support)
 - Domain S: Security (no mainline support).
 - Domain F: LCD (driver already uses runtime PM), post processing and
   rotation (no mainline support).

The IROM domain is marked as always enabled as we should arrange for it
to be enabled when we suspend which will need a bit more work.

Due to all the conditional device registration that the platform does
wrap s3c_pm_init() with s3c64xx_pm_init() which actually puts the device
into the power domain after the machines have registered, looking for
platform data to tell if the device was registered. Since currently only
Cragganmore actually sets up PM that is the only machine updated.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

arch/arm/mach-s3c64xx/Kconfig

@@ -8,6 +8,7 @@ config PLAT_S3C64XX
 	bool
 	depends on ARCH_S3C64XX
 	select SAMSUNG_WAKEMASK
+	select PM_GENERIC_DOMAINS
 	default y
 	help
 	  Base platform code for any Samsung S3C64XX device

arch/arm/mach-s3c64xx/mach-crag6410.c

@@ -704,7 +704,7 @@ static void __init crag6410_machine_init(void)
 
 	regulator_has_full_constraints();
 
-	s3c_pm_init();
+	s3c64xx_pm_init();
 }
 
 MACHINE_START(WLF_CRAGG_6410, "Wolfson Cragganmore 6410")

arch/arm/mach-s3c64xx/pm.c

@@ -17,10 +17,12 @@
 #include <linux/serial_core.h>
 #include <linux/io.h>
 #include <linux/gpio.h>
+#include <linux/pm_domain.h>
 
 #include <mach/map.h>
 #include <mach/irqs.h>
 
+#include <plat/devs.h>
 #include <plat/pm.h>
 #include <plat/wakeup-mask.h>
 
@@ -31,6 +33,148 @@
 #include <mach/regs-gpio-memport.h>
 #include <mach/regs-modem.h>
 
+struct s3c64xx_pm_domain {
+	char *const name;
+	u32 ena;
+	u32 pwr_stat;
+	struct generic_pm_domain pd;
+};
+
+static int s3c64xx_pd_off(struct generic_pm_domain *domain)
+{
+	struct s3c64xx_pm_domain *pd;
+	u32 val;
+
+	pd = container_of(domain, struct s3c64xx_pm_domain, pd);
+
+	val = __raw_readl(S3C64XX_NORMAL_CFG);
+	val &= ~(pd->ena);
+	__raw_writel(val, S3C64XX_NORMAL_CFG);
+
+	return 0;
+}
+
+static int s3c64xx_pd_on(struct generic_pm_domain *domain)
+{
+	struct s3c64xx_pm_domain *pd;
+	u32 val;
+	long retry = 1000000L;
+
+	pd = container_of(domain, struct s3c64xx_pm_domain, pd);
+
+	val = __raw_readl(S3C64XX_NORMAL_CFG);
+	val |= pd->ena;
+	__raw_writel(val, S3C64XX_NORMAL_CFG);
+
+	/* Not all domains provide power status readback */
+	if (pd->pwr_stat) {
+		do {
+			cpu_relax();
+			if (__raw_readl(S3C64XX_BLK_PWR_STAT) & pd->pwr_stat)
+				break;
+		} while (retry--);
+
+		if (!retry) {
+			pr_err("Failed to start domain %s\n", pd->name);
+			return -EBUSY;
+		}
+	}
+
+	return 0;
+}
+
+static struct s3c64xx_pm_domain s3c64xx_pm_irom = {
+	.name = "IROM",
+	.ena = S3C64XX_NORMALCFG_IROM_ON,
+	.pd = {
+		.power_off = s3c64xx_pd_off,
+		.power_on = s3c64xx_pd_on,
+	},
+};
+
+static struct s3c64xx_pm_domain s3c64xx_pm_etm = {
+	.name = "ETM",
+	.ena = S3C64XX_NORMALCFG_DOMAIN_ETM_ON,
+	.pwr_stat = S3C64XX_BLKPWRSTAT_ETM,
+	.pd = {
+		.power_off = s3c64xx_pd_off,
+		.power_on = s3c64xx_pd_on,
+	},
+};
+
+static struct s3c64xx_pm_domain s3c64xx_pm_s = {
+	.name = "S",
+	.ena = S3C64XX_NORMALCFG_DOMAIN_S_ON,
+	.pwr_stat = S3C64XX_BLKPWRSTAT_S,
+	.pd = {
+		.power_off = s3c64xx_pd_off,
+		.power_on = s3c64xx_pd_on,
+	},
+};
+
+static struct s3c64xx_pm_domain s3c64xx_pm_f = {
+	.name = "F",
+	.ena = S3C64XX_NORMALCFG_DOMAIN_F_ON,
+	.pwr_stat = S3C64XX_BLKPWRSTAT_F,
+	.pd = {
+		.power_off = s3c64xx_pd_off,
+		.power_on = s3c64xx_pd_on,
+	},
+};
+
+static struct s3c64xx_pm_domain s3c64xx_pm_p = {
+	.name = "P",
+	.ena = S3C64XX_NORMALCFG_DOMAIN_P_ON,
+	.pwr_stat = S3C64XX_BLKPWRSTAT_P,
+	.pd = {
+		.power_off = s3c64xx_pd_off,
+		.power_on = s3c64xx_pd_on,
+	},
+};
+
+static struct s3c64xx_pm_domain s3c64xx_pm_i = {
+	.name = "I",
+	.ena = S3C64XX_NORMALCFG_DOMAIN_I_ON,
+	.pwr_stat = S3C64XX_BLKPWRSTAT_I,
+	.pd = {
+		.power_off = s3c64xx_pd_off,
+		.power_on = s3c64xx_pd_on,
+	},
+};
+
+static struct s3c64xx_pm_domain s3c64xx_pm_g = {
+	.name = "G",
+	.ena = S3C64XX_NORMALCFG_DOMAIN_G_ON,
+	.pd = {
+		.power_off = s3c64xx_pd_off,
+		.power_on = s3c64xx_pd_on,
+	},
+};
+
+static struct s3c64xx_pm_domain s3c64xx_pm_v = {
+	.name = "V",
+	.ena = S3C64XX_NORMALCFG_DOMAIN_V_ON,
+	.pwr_stat = S3C64XX_BLKPWRSTAT_V,
+	.pd = {
+		.power_off = s3c64xx_pd_off,
+		.power_on = s3c64xx_pd_on,
+	},
+};
+
+static struct s3c64xx_pm_domain *s3c64xx_always_on_pm_domains[] = {
+	&s3c64xx_pm_irom,
+};
+
+static struct s3c64xx_pm_domain *s3c64xx_pm_domains[] = {
+	&s3c64xx_pm_etm,
+	&s3c64xx_pm_g,
+	&s3c64xx_pm_v,
+	&s3c64xx_pm_i,
+	&s3c64xx_pm_p,
+	&s3c64xx_pm_s,
+	&s3c64xx_pm_f,
+};
+
 #ifdef CONFIG_S3C_PM_DEBUG_LED_SMDK
 void s3c_pm_debug_smdkled(u32 set, u32 clear)
 {
@@ -89,6 +233,8 @@ static struct sleep_save misc_save[] = {
 
 	SAVE_ITEM(S3C64XX_SDMA_SEL),
 	SAVE_ITEM(S3C64XX_MODEM_MIFPCON),
+
+	SAVE_ITEM(S3C64XX_NORMAL_CFG),
 };
 
 void s3c_pm_configure_extint(void)
@@ -179,7 +325,26 @@ static void s3c64xx_pm_prepare(void)
 	__raw_writel(__raw_readl(S3C64XX_WAKEUP_STAT), S3C64XX_WAKEUP_STAT);
 }
 
-static int s3c64xx_pm_init(void)
+int __init s3c64xx_pm_init(void)
+{
+	int i;
+
+	s3c_pm_init();
+
+	for (i = 0; i < ARRAY_SIZE(s3c64xx_always_on_pm_domains); i++)
+		pm_genpd_init(&s3c64xx_always_on_pm_domains[i]->pd,
+			      &pm_domain_always_on_gov, false);
+
+	for (i = 0; i < ARRAY_SIZE(s3c64xx_pm_domains); i++)
+		pm_genpd_init(&s3c64xx_pm_domains[i]->pd, NULL, false);
+
+	if (dev_get_platdata(&s3c_device_fb.dev))
+		pm_genpd_add_device(&s3c64xx_pm_f.pd, &s3c_device_fb.dev);
+
+	return 0;
+}
+
+static __init int s3c64xx_pm_initcall(void)
 {
 	pm_cpu_prep = s3c64xx_pm_prepare;
 	pm_cpu_sleep = s3c64xx_cpu_suspend;
@@ -198,5 +363,12 @@ static int s3c64xx_pm_init(void)
 
 	return 0;
 }
+arch_initcall(s3c64xx_pm_initcall);
+
+static __init int s3c64xx_pm_late_initcall(void)
+{
+	pm_genpd_poweroff_unused();
 
-arch_initcall(s3c64xx_pm_init);
+	return 0;
+}
+late_initcall(s3c64xx_pm_late_initcall);

arch/arm/plat-samsung/include/plat/pm.h

@@ -22,6 +22,7 @@ struct sys_device;
 #ifdef CONFIG_PM
 
 extern __init int s3c_pm_init(void);
+extern __init int s3c64xx_pm_init(void);
 
 #else
 
@@ -29,6 +30,11 @@ static inline int s3c_pm_init(void)
 {
 	return 0;
 }
+
+static inline int s3c64xx_pm_init(void)
+{
+	return 0;
+}
 #endif
 
 /* configuration for the IRQ mask over sleep */