[PATCH v2 2/2] ARM: EXYNOS: Add support for firmware-assisted suspend/resume
Tomasz Figa
t.figa at samsung.com
Thu Jul 17 08:56:11 PDT 2014
On a numer of Exynos-based boards Linux kernel is running in non-secure
mode under a secure firmware. This means that certain operations need to
be handled in special way, with firmware assistance. System-wide
suspend/resume is an example of such operations.
This patch adds support for firmware-assisted suspend/resume by
leveraging recently introduced suspend and resume firmware operations
and modifying existing suspend/resume paths to account for presence of
secure firmware.
Signed-off-by: Tomasz Figa <t.figa at samsung.com>
---
arch/arm/mach-exynos/Makefile | 1 +
arch/arm/mach-exynos/common.h | 4 ++++
arch/arm/mach-exynos/firmware.c | 45 +++++++++++++++++++++++++++++++++++++++++
arch/arm/mach-exynos/pm.c | 16 ++++++++++-----
arch/arm/mach-exynos/sleep.S | 28 +++++++++++++++++++++++++
arch/arm/mach-exynos/smc.h | 4 ++++
6 files changed, 93 insertions(+), 5 deletions(-)
diff --git a/arch/arm/mach-exynos/Makefile b/arch/arm/mach-exynos/Makefile
index 788f26d..e7d1774 100644
--- a/arch/arm/mach-exynos/Makefile
+++ b/arch/arm/mach-exynos/Makefile
@@ -26,6 +26,7 @@ CFLAGS_hotplug.o += -march=armv7-a
plus_sec := $(call as-instr,.arch_extension sec,+sec)
AFLAGS_exynos-smc.o :=-Wa,-march=armv7-a$(plus_sec)
+AFLAGS_sleep.o :=-Wa,-march=armv7-a$(plus_sec)
obj-$(CONFIG_EXYNOS5420_MCPM) += mcpm-exynos.o
CFLAGS_mcpm-exynos.o += -march=armv7-a
diff --git a/arch/arm/mach-exynos/common.h b/arch/arm/mach-exynos/common.h
index f8daa9c..a3f3061 100644
--- a/arch/arm/mach-exynos/common.h
+++ b/arch/arm/mach-exynos/common.h
@@ -111,6 +111,9 @@ IS_SAMSUNG_CPU(exynos5800, EXYNOS5800_SOC_ID, EXYNOS5_SOC_MASK)
#define soc_is_exynos5() (soc_is_exynos5250() || soc_is_exynos5410() || \
soc_is_exynos5420() || soc_is_exynos5800())
+extern u32 cp15_save_diag;
+extern u32 cp15_save_power;
+
extern void __iomem *sysram_ns_base_addr;
extern void __iomem *sysram_base_addr;
extern void __iomem *pmu_base_addr;
@@ -127,6 +130,7 @@ static inline void exynos_pm_init(void) {}
#endif
extern void exynos_cpu_resume(void);
+extern void exynos_cpu_resume_ns(void);
extern struct smp_operations exynos_smp_ops;
diff --git a/arch/arm/mach-exynos/firmware.c b/arch/arm/mach-exynos/firmware.c
index e8797bb..f5e626d 100644
--- a/arch/arm/mach-exynos/firmware.c
+++ b/arch/arm/mach-exynos/firmware.c
@@ -14,13 +14,20 @@
#include <linux/of.h>
#include <linux/of_address.h>
+#include <asm/cacheflush.h>
+#include <asm/cputype.h>
#include <asm/firmware.h>
+#include <asm/suspend.h>
#include <mach/map.h>
#include "common.h"
#include "smc.h"
+#define EXYNOS_SLEEP_MAGIC 0x00000bad
+#define EXYNOS_BOOT_ADDR 0x8
+#define EXYNOS_BOOT_FLAG 0xc
+
static int exynos_do_idle(void)
{
exynos_smc(SMC_CMD_SLEEP, 0, 0, 0);
@@ -69,10 +76,48 @@ static int exynos_set_cpu_boot_addr(int cpu, unsigned long boot_addr)
return 0;
}
+static int exynos_cpu_suspend(unsigned long arg)
+{
+ flush_cache_all();
+ outer_flush_all();
+
+ exynos_smc(SMC_CMD_SLEEP, 0, 0, 0);
+
+ pr_info("Failed to suspend the system\n");
+ writel(0, sysram_ns_base_addr + EXYNOS_BOOT_FLAG);
+ return 1;
+}
+
+static int exynos_suspend(void)
+{
+ if (read_cpuid_part() == ARM_CPU_PART_CORTEX_A9) {
+ /* Save Power control and Diagnostic registers */
+ asm ("mrc p15, 0, %0, c15, c0, 0\n"
+ "mrc p15, 0, %1, c15, c0, 1\n"
+ : "=r" (cp15_save_power), "=r" (cp15_save_diag)
+ : : "cc");
+ }
+
+ writel(EXYNOS_SLEEP_MAGIC, sysram_ns_base_addr + EXYNOS_BOOT_FLAG);
+ writel(virt_to_phys(exynos_cpu_resume_ns),
+ sysram_ns_base_addr + EXYNOS_BOOT_ADDR);
+
+ return cpu_suspend(0, exynos_cpu_suspend);
+}
+
+static int exynos_resume(void)
+{
+ writel(0, sysram_ns_base_addr + EXYNOS_BOOT_FLAG);
+
+ return 0;
+}
+
static const struct firmware_ops exynos_firmware_ops = {
.do_idle = exynos_do_idle,
.set_cpu_boot_addr = exynos_set_cpu_boot_addr,
.cpu_boot = exynos_cpu_boot,
+ .suspend = exynos_suspend,
+ .resume = exynos_resume,
};
void __init exynos_firmware_init(void)
diff --git a/arch/arm/mach-exynos/pm.c b/arch/arm/mach-exynos/pm.c
index 63a1d6b..681e894 100644
--- a/arch/arm/mach-exynos/pm.c
+++ b/arch/arm/mach-exynos/pm.c
@@ -23,6 +23,7 @@
#include <linux/clk.h>
#include <asm/cacheflush.h>
+#include <asm/firmware.h>
#include <asm/hardware/cache-l2x0.h>
#include <asm/smp_scu.h>
#include <asm/suspend.h>
@@ -354,12 +355,11 @@ static int exynos_pm_suspend(void)
static void exynos_pm_resume(void)
{
+ u32 cpuid = read_cpuid_part();
+
if (exynos_pm_central_resume())
goto early_wakeup;
- if (read_cpuid_part() == ARM_CPU_PART_CORTEX_A9)
- exynos_cpu_restore_register();
-
/* For release retention */
__raw_writel((1 << 28), S5P_PAD_RET_MAUDIO_OPTION);
@@ -376,9 +376,13 @@ static void exynos_pm_resume(void)
s3c_pm_do_restore_core(exynos_core_save, ARRAY_SIZE(exynos_core_save));
- if (read_cpuid_part() == ARM_CPU_PART_CORTEX_A9)
+ if (cpuid == ARM_CPU_PART_CORTEX_A9)
scu_enable(S5P_VA_SCU);
+ if (call_firmware_op(resume) == -ENOSYS
+ && cpuid == ARM_CPU_PART_CORTEX_A9)
+ exynos_cpu_restore_register();
+
early_wakeup:
/* Clear SLEEP mode set in INFORM1 */
@@ -419,7 +423,9 @@ static int exynos_suspend_enter(suspend_state_t state)
flush_cache_all();
s3c_pm_check_store();
- ret = cpu_suspend(0, exynos_cpu_suspend);
+ ret = call_firmware_op(suspend);
+ if (ret == -ENOSYS)
+ ret = cpu_suspend(0, exynos_cpu_suspend);
if (ret)
return ret;
diff --git a/arch/arm/mach-exynos/sleep.S b/arch/arm/mach-exynos/sleep.S
index 108a45f..e3c3730 100644
--- a/arch/arm/mach-exynos/sleep.S
+++ b/arch/arm/mach-exynos/sleep.S
@@ -16,6 +16,7 @@
*/
#include <linux/linkage.h>
+#include "smc.h"
#define CPU_MASK 0xff0ffff0
#define CPU_CORTEX_A9 0x410fc090
@@ -55,3 +56,30 @@ ENTRY(exynos_cpu_resume)
#endif
b cpu_resume
ENDPROC(exynos_cpu_resume)
+
+ .align
+
+ENTRY(exynos_cpu_resume_ns)
+ mrc p15, 0, r0, c0, c0, 0
+ ldr r1, =CPU_MASK
+ and r0, r0, r1
+ ldr r1, =CPU_CORTEX_A9
+ cmp r0, r1
+ bne skip_cp15
+
+ adr r0, cp15_save_power
+ ldr r1, [r0]
+ adr r0, cp15_save_diag
+ ldr r2, [r0]
+ mov r0, #SMC_CMD_C15RESUME
+ dsb
+ smc #0
+skip_cp15:
+ b cpu_resume
+ENDPROC(exynos_cpu_resume_ns)
+ .globl cp15_save_diag
+cp15_save_diag:
+ .long 0 @ cp15 diagnostic
+ .globl cp15_save_power
+cp15_save_power:
+ .long 0 @ cp15 power control
diff --git a/arch/arm/mach-exynos/smc.h b/arch/arm/mach-exynos/smc.h
index 13a1dc8..f7b82f9 100644
--- a/arch/arm/mach-exynos/smc.h
+++ b/arch/arm/mach-exynos/smc.h
@@ -26,6 +26,10 @@
#define SMC_CMD_L2X0INVALL (-24)
#define SMC_CMD_L2X0DEBUG (-25)
+#ifndef __ASSEMBLY__
+
extern void exynos_smc(u32 cmd, u32 arg1, u32 arg2, u32 arg3);
+#endif /* __ASSEMBLY__ */
+
#endif
--
1.9.3
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