ARM: EXYNOS: Add support for firmware-assisted suspend/resume

This patch adds firmware ops related to system suspend/resume that
allows suspend/resume of systems with secure firmware.

Signed-off-by: Tomasz Figa <t.figa@samsung.com>

diff --git a/arch/arm/include/asm/firmware.h b/arch/arm/include/asm/firmware.h
index 1563130..f459d25 100644 (file)
--- a/arch/arm/include/asm/firmware.h
+++ b/arch/arm/include/asm/firmware.h
@@ -37,6 +37,18 @@ struct firmware_ops {
         * Initializes L2 cache
         */
        int (*l2x0_init)(void);
+       /*
+        * Suspends the system
+        */
+       int (*suspend)(unsigned long resume_addr);
+       /*
+        * Acknowledges system resume
+        */
+       int (*resume)(void);
+       /*
+        * Restores coprocessor 15 registers
+        */
+       int (*c15resume)(u32 *regs);
 };
 
 /* Global pointer for current firmware_ops structure, can't be NULL. */

diff --git a/arch/arm/mach-exynos/firmware.c b/arch/arm/mach-exynos/firmware.c
index da5fb26..3f98bf7 100644 (file)
--- a/arch/arm/mach-exynos/firmware.c
+++ b/arch/arm/mach-exynos/firmware.c
@@ -20,6 +20,8 @@
 
 #include "smc.h"
 
+#define EXYNOS_SLEEP_MAGIC     0x00000BAD
+
 static int exynos_do_idle(void)
 {
        exynos_smc(SMC_CMD_SLEEP, 0, 0, 0);
@@ -47,11 +49,37 @@ static int exynos_l2x0_init(void)
        return 0;
 }
 
+static int exynos_suspend(unsigned long resume_addr)
+{
+       writel(EXYNOS_SLEEP_MAGIC, S5P_VA_SYSRAM_NS + 0xC);
+       writel(resume_addr, S5P_VA_SYSRAM_NS + 0x8);
+       exynos_smc(SMC_CMD_SLEEP, 0, 0, 0);
+
+       return 0;
+}
+
+static int exynos_resume(void)
+{
+       writel(0, S5P_VA_SYSRAM_NS + 0xC);
+
+       return 0;
+}
+
+static int exynos_c15resume(u32 *regs)
+{
+       exynos_smc(SMC_CMD_C15RESUME, regs[0], regs[1], 0);
+
+       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,
        .l2x0_init      = exynos_l2x0_init,
+       .suspend        = exynos_suspend,
+       .resume         = exynos_resume,
+       .c15resume      = exynos_c15resume,
 };
 
 void __init exynos_firmware_init(void)

diff --git a/arch/arm/mach-exynos/pm.c b/arch/arm/mach-exynos/pm.c
index 83c4999..e195e3e 100644 (file)
--- a/arch/arm/mach-exynos/pm.c
+++ b/arch/arm/mach-exynos/pm.c
@@ -36,6 +36,7 @@
 #include <mach/pm-core.h>
 
 #include "common.h"
+#include "smc.h"
 
 static struct sleep_save exynos4_set_clksrc[] = {
        { .reg = EXYNOS4_CLKSRC_MASK_TOP                , .val = 0x00000001, },
@@ -88,7 +89,8 @@ static int exynos_cpu_suspend(unsigned long arg)
 #endif
 
        /* issue the standby signal into the pm unit. */
-       cpu_do_idle();
+       if (call_firmware_op(suspend, virt_to_phys(s3c_cpu_resume)) == -ENOSYS)
+               cpu_do_idle();
 
        pr_info("Failed to suspend the system\n");
        return 1; /* Aborting suspend */
@@ -286,7 +288,9 @@ static void exynos_pm_resume(void)
                /* No need to perform below restore code */
                goto early_wakeup;
        }
-       if (!soc_is_exynos5250()) {
+       if (!soc_is_exynos5250()
+           && call_firmware_op(c15resume, save_arm_register) == -ENOSYS)
+       {
                /* Restore Power control register */
                tmp = save_arm_register[0];
                asm volatile ("mcr p15, 0, %0, c15, c0, 0"
@@ -328,6 +332,7 @@ early_wakeup:
 
        /* Clear SLEEP mode set in INFORM1 */
        __raw_writel(0x0, S5P_INFORM1);
+       call_firmware_op(resume);
 
        return;
 }