[PATCH 2/2] ARM: OMAP2+: sleep43xx: Add RTC-Mode support
From: Keerthy
Date: Wed Jul 04 2018 - 06:08:04 EST
Add support for RTC mode to low level suspend code. This includes
providing the rtc base address for the assembly code to configuring the
PMIC_PWR_EN line late in suspend to enter RTC+DDR mode.
Signed-off-by: Dave Gerlach <d-gerlach@xxxxxx>
Signed-off-by: Keerthy <j-keerthy@xxxxxx>
---
arch/arm/mach-omap2/pm-asm-offsets.c | 2 ++
arch/arm/mach-omap2/pm33xx-core.c | 10 +++++++
arch/arm/mach-omap2/sleep33xx.S | 8 +++--
arch/arm/mach-omap2/sleep43xx.S | 57 ++++++++++++++++++++++++++++++++++--
drivers/soc/ti/pm33xx.c | 1 +
include/linux/platform_data/pm33xx.h | 3 ++
6 files changed, 77 insertions(+), 4 deletions(-)
diff --git a/arch/arm/mach-omap2/pm-asm-offsets.c b/arch/arm/mach-omap2/pm-asm-offsets.c
index b9846b1..d202306 100644
--- a/arch/arm/mach-omap2/pm-asm-offsets.c
+++ b/arch/arm/mach-omap2/pm-asm-offsets.c
@@ -27,6 +27,8 @@ int main(void)
offsetof(struct am33xx_pm_ro_sram_data, amx3_pm_sram_data_virt));
DEFINE(AMX3_PM_RO_SRAM_DATA_PHYS_OFFSET,
offsetof(struct am33xx_pm_ro_sram_data, amx3_pm_sram_data_phys));
+ DEFINE(AMX3_PM_RTC_BASE_VIRT_OFFSET,
+ offsetof(struct am33xx_pm_ro_sram_data, rtc_base_virt));
DEFINE(AMX3_PM_RO_SRAM_DATA_SIZE,
sizeof(struct am33xx_pm_ro_sram_data));
diff --git a/arch/arm/mach-omap2/pm33xx-core.c b/arch/arm/mach-omap2/pm33xx-core.c
index e363b97..f4971e4 100644
--- a/arch/arm/mach-omap2/pm33xx-core.c
+++ b/arch/arm/mach-omap2/pm33xx-core.c
@@ -26,6 +26,7 @@
static struct powerdomain *cefuse_pwrdm, *gfx_pwrdm, *per_pwrdm, *mpu_pwrdm;
static struct clockdomain *gfx_l4ls_clkdm;
static void __iomem *scu_base;
+static struct omap_hwmod *rtc_oh;
static int __init am43xx_map_scu(void)
{
@@ -153,16 +154,25 @@ static struct am33xx_pm_sram_addr *amx3_get_sram_addrs(void)
return NULL;
}
+void __iomem *am43xx_get_rtc_base_addr(void)
+{
+ rtc_oh = omap_hwmod_lookup("rtc");
+
+ return omap_hwmod_get_mpu_rt_va(rtc_oh);
+}
+
static struct am33xx_pm_platform_data am33xx_ops = {
.init = am33xx_suspend_init,
.soc_suspend = am33xx_suspend,
.get_sram_addrs = amx3_get_sram_addrs,
+ .get_rtc_base_addr = am43xx_get_rtc_base_addr,
};
static struct am33xx_pm_platform_data am43xx_ops = {
.init = am43xx_suspend_init,
.soc_suspend = am43xx_suspend,
.get_sram_addrs = amx3_get_sram_addrs,
+ .get_rtc_base_addr = am43xx_get_rtc_base_addr,
};
static struct am33xx_pm_platform_data *am33xx_pm_get_pdata(void)
diff --git a/arch/arm/mach-omap2/sleep33xx.S b/arch/arm/mach-omap2/sleep33xx.S
index 3ef469f..47a8164 100644
--- a/arch/arm/mach-omap2/sleep33xx.S
+++ b/arch/arm/mach-omap2/sleep33xx.S
@@ -20,6 +20,9 @@
#define AM33XX_CM_CLKCTRL_MODULEMODE_DISABLE 0x0003
#define AM33XX_CM_CLKCTRL_MODULEMODE_ENABLE 0x0002
+/* replicated define because linux/bitops.h cannot be included in assembly */
+#define BIT(nr) (1 << (nr))
+
.arm
.align 3
@@ -225,8 +228,6 @@ ENDPROC(am33xx_resume_from_deep_sleep)
* Local variables
*/
.align
-resume_addr:
- .word cpu_resume - PAGE_OFFSET + 0x80000000
kernel_flush:
.word v7_flush_dcache_all
virt_mpu_clkctrl:
@@ -249,6 +250,9 @@ ENTRY(am33xx_pm_sram)
.word am33xx_emif_sram_table
.word am33xx_pm_ro_sram_data
+resume_addr:
+.word cpu_resume - PAGE_OFFSET + 0x80000000
+
.align 3
ENTRY(am33xx_pm_ro_sram_data)
.space AMX3_PM_RO_SRAM_DATA_SIZE
diff --git a/arch/arm/mach-omap2/sleep43xx.S b/arch/arm/mach-omap2/sleep43xx.S
index 0553adb..5b9343b 100644
--- a/arch/arm/mach-omap2/sleep43xx.S
+++ b/arch/arm/mach-omap2/sleep43xx.S
@@ -22,6 +22,9 @@
#include "prm33xx.h"
#include "prcm43xx.h"
+/* replicated define because linux/bitops.h cannot be included in assembly */
+#define BIT(nr) (1 << (nr))
+
#define AM33XX_CM_CLKCTRL_MODULESTATE_DISABLED 0x00030000
#define AM33XX_CM_CLKCTRL_MODULEMODE_DISABLE 0x0003
#define AM33XX_CM_CLKCTRL_MODULEMODE_ENABLE 0x0002
@@ -45,6 +48,13 @@
AM43XX_CM_PER_EMIF_CLKCTRL_OFFSET)
#define AM43XX_PRM_EMIF_CTRL_OFFSET 0x0030
+#define RTC_SECONDS_REG 0x0
+#define RTC_PMIC_REG 0x98
+#define RTC_PMIC_POWER_EN BIT(16)
+#define RTC_PMIC_EXT_WAKEUP_STS BIT(12)
+#define RTC_PMIC_EXT_WAKEUP_POL BIT(4)
+#define RTC_PMIC_EXT_WAKEUP_EN BIT(0)
+
.arm
.align 3
@@ -144,6 +154,20 @@ sync:
ldr r4, [r2, #AMX3_PM_WFI_FLAGS_OFFSET]
cache_skip_flush:
+ /*
+ * If we are trying to enter RTC+DDR mode we must perform
+ * a read from the rtc address space to ensure translation
+ * presence in the TLB to avoid page table walk after DDR
+ * is unavailable.
+ */
+ tst r4, #WFI_FLAG_RTC_ONLY
+ beq skip_rtc_va_refresh
+
+ adr r3, am43xx_pm_ro_sram_data
+ ldr r1, [r3, #AMX3_PM_RTC_BASE_VIRT_OFFSET]
+ ldr r0, [r1]
+
+skip_rtc_va_refresh:
/* Check if we want self refresh */
tst r4, #WFI_FLAG_SELF_REFRESH
beq emif_skip_enter_sr
@@ -179,6 +203,34 @@ wait_emif_disable:
bne wait_emif_disable
emif_skip_disable:
+ tst r4, #WFI_FLAG_RTC_ONLY
+ beq skip_rtc_only
+
+ adr r3, am43xx_pm_ro_sram_data
+ ldr r1, [r3, #AMX3_PM_RTC_BASE_VIRT_OFFSET]
+
+ ldr r0, [r1, #RTC_PMIC_REG]
+ orr r0, r0, #RTC_PMIC_POWER_EN
+ orr r0, r0, #RTC_PMIC_EXT_WAKEUP_STS
+ orr r0, r0, #RTC_PMIC_EXT_WAKEUP_EN
+ orr r0, r0, #RTC_PMIC_EXT_WAKEUP_POL
+ str r0, [r1, #RTC_PMIC_REG]
+ ldr r0, [r1, #RTC_PMIC_REG]
+ /* Wait for 2 seconds to lose power */
+ mov r3, #2
+ ldr r2, [r1, #RTC_SECONDS_REG]
+rtc_loop:
+ ldr r0, [r1, #RTC_SECONDS_REG]
+ cmp r0, r2
+ beq rtc_loop
+ mov r2, r0
+ subs r3, r3, #1
+ bne rtc_loop
+
+ b re_enable_emif
+
+skip_rtc_only:
+
tst r4, #WFI_FLAG_WAKE_M3
beq wkup_m3_skip
@@ -244,6 +296,7 @@ wkup_m3_skip:
mov r2, #AM33XX_CM_CLKCTRL_MODULEMODE_ENABLE
str r2, [r1]
+re_enable_emif:
/* Re-enable EMIF */
ldr r1, am43xx_virt_emif_clkctrl
mov r2, #AM33XX_CM_CLKCTRL_MODULEMODE_ENABLE
@@ -378,8 +431,6 @@ ENDPROC(am43xx_resume_from_deep_sleep)
* Local variables
*/
.align
-resume_addr:
- .word cpu_resume - PAGE_OFFSET + 0x80000000
kernel_flush:
.word v7_flush_dcache_all
ddr_start:
@@ -426,6 +477,8 @@ ENTRY(am43xx_pm_sram)
.word am43xx_emif_sram_table
.word am43xx_pm_ro_sram_data
+resume_addr:
+ .word cpu_resume - PAGE_OFFSET + 0x80000000
.align 3
ENTRY(am43xx_pm_ro_sram_data)
diff --git a/drivers/soc/ti/pm33xx.c b/drivers/soc/ti/pm33xx.c
index 0011c8f..d0dab32 100644
--- a/drivers/soc/ti/pm33xx.c
+++ b/drivers/soc/ti/pm33xx.c
@@ -229,6 +229,7 @@ static int am33xx_push_sram_idle(void)
ro_sram_data.amx3_pm_sram_data_virt = ocmcram_location_data;
ro_sram_data.amx3_pm_sram_data_phys =
gen_pool_virt_to_phys(sram_pool_data, ocmcram_location_data);
+ ro_sram_data.rtc_base_virt = pm_ops->get_rtc_base_addr();
/* Save physical address to calculate resume offset during pm init */
am33xx_do_wfi_sram_phys = gen_pool_virt_to_phys(sram_pool,
diff --git a/include/linux/platform_data/pm33xx.h b/include/linux/platform_data/pm33xx.h
index d231265..fbf5ed7 100644
--- a/include/linux/platform_data/pm33xx.h
+++ b/include/linux/platform_data/pm33xx.h
@@ -42,6 +42,7 @@ struct am33xx_pm_sram_addr {
unsigned long *resume_offset;
unsigned long *emif_sram_table;
unsigned long *ro_sram_data;
+ unsigned long resume_address;
};
struct am33xx_pm_platform_data {
@@ -49,6 +50,7 @@ struct am33xx_pm_platform_data {
int (*soc_suspend)(unsigned int state, int (*fn)(unsigned long),
unsigned long args);
struct am33xx_pm_sram_addr *(*get_sram_addrs)(void);
+ void __iomem *(*get_rtc_base_addr)(void);
};
struct am33xx_pm_sram_data {
@@ -60,6 +62,7 @@ struct am33xx_pm_sram_data {
struct am33xx_pm_ro_sram_data {
u32 amx3_pm_sram_data_virt;
u32 amx3_pm_sram_data_phys;
+ void __iomem *rtc_base_virt;
} __packed __aligned(8);
#endif /* __ASSEMBLER__ */
--
1.9.1