Use the MCPM layer to handle core suspend/resume on Exynos5420. Also, restore the entry address setup code post-resume. Signed-off-by: Abhilash Kesavan <a.kesavan@xxxxxxxxxxx> Acked-by: Nicolas Pitre <nico@xxxxxxxxxx> --- Changes in v2: - Made use of the MCPM suspend/powered_up call-backs Changes in v3: - Used the residency value to indicate the entered state Changes in v4: - Checked if MCPM has been enabled to prevent build error Changes in v5: - Removed the MCPM flags and just used a local flag to indicate that we are suspending. Changes in v6: - Read the SYS_PWR_REG value to decide if we are suspending the system. - Restore the SYS_PWR_REG value post-resume. - Modified the comments to reflect the first change. Changes in v7: - Add the suspend check in exynos_cpu_power_down() rather than the MCPM back-end. - Clean-up unnecessary changes related to earlier versions. Changes in v8: - Rebased on the latest exynos PMU/PM support patches. Changes in v9: - Fixed rebasing issues in v8 - Used pmu_raw_readl instead of __raw_readl This patch is based on kgene's for-next branch. http://git.kernel.org/cgit/linux/kernel/git/kgene/linux-samsung.git/log/?h=for-next Here are the dependencies: 1) Decouple syscon interface from platform devices - v7 http://lkml.org/lkml/2014/9/30/156 2) ARM: Exynos: Convert PMU implementation into a platform driver - v9 https://lkml.org/lkml/2014/10/6/89 3) Exynos5420 PMU/S2R Series - v9 http://www.spinics.net/lists/arm-kernel/msg368207.html arch/arm/mach-exynos/mcpm-exynos.c | 32 +++++++++++++++-------- arch/arm/mach-exynos/platsmp.c | 12 +++++++++ arch/arm/mach-exynos/suspend.c | 49 ++++++++++++++++++++++++++++++++---- 3 files changed, 78 insertions(+), 15 deletions(-) diff --git a/arch/arm/mach-exynos/mcpm-exynos.c b/arch/arm/mach-exynos/mcpm-exynos.c index dc9a764..b0d3c2e 100644 --- a/arch/arm/mach-exynos/mcpm-exynos.c +++ b/arch/arm/mach-exynos/mcpm-exynos.c @@ -15,6 +15,7 @@ #include <linux/delay.h> #include <linux/io.h> #include <linux/of_address.h> +#include <linux/syscore_ops.h> #include <asm/cputype.h> #include <asm/cp15.h> @@ -30,6 +31,8 @@ #define EXYNOS5420_USE_ARM_CORE_DOWN_STATE BIT(29) #define EXYNOS5420_USE_L2_COMMON_UP_STATE BIT(30) +static void __iomem *ns_sram_base_addr; + /* * The common v7_exit_coherency_flush API could not be used because of the * Erratum 799270 workaround. This macro is the same as the common one (in @@ -318,10 +321,26 @@ static const struct of_device_id exynos_dt_mcpm_match[] = { {}, }; +static void exynos_mcpm_setup_entry_point(void) +{ + /* + * U-Boot SPL is hardcoded to jump to the start of ns_sram_base_addr + * as part of secondary_cpu_start(). Let's redirect it to the + * mcpm_entry_point(). This is done during both secondary boot-up as + * well as system resume. + */ + __raw_writel(0xe59f0000, ns_sram_base_addr); /* ldr r0, [pc, #0] */ + __raw_writel(0xe12fff10, ns_sram_base_addr + 4); /* bx r0 */ + __raw_writel(virt_to_phys(mcpm_entry_point), ns_sram_base_addr + 8); +} + +static struct syscore_ops exynos_mcpm_syscore_ops = { + .resume = exynos_mcpm_setup_entry_point, +}; + static int __init exynos_mcpm_init(void) { struct device_node *node; - void __iomem *ns_sram_base_addr; unsigned int value, i; int ret; @@ -387,16 +406,9 @@ static int __init exynos_mcpm_init(void) pmu_raw_writel(value, EXYNOS_COMMON_OPTION(i)); } - /* - * U-Boot SPL is hardcoded to jump to the start of ns_sram_base_addr - * as part of secondary_cpu_start(). Let's redirect it to the - * mcpm_entry_point(). - */ - __raw_writel(0xe59f0000, ns_sram_base_addr); /* ldr r0, [pc, #0] */ - __raw_writel(0xe12fff10, ns_sram_base_addr + 4); /* bx r0 */ - __raw_writel(virt_to_phys(mcpm_entry_point), ns_sram_base_addr + 8); + exynos_mcpm_setup_entry_point(); - iounmap(ns_sram_base_addr); + register_syscore_ops(&exynos_mcpm_syscore_ops); return ret; } diff --git a/arch/arm/mach-exynos/platsmp.c b/arch/arm/mach-exynos/platsmp.c index adb36a8..7a1ebfe 100644 --- a/arch/arm/mach-exynos/platsmp.c +++ b/arch/arm/mach-exynos/platsmp.c @@ -126,6 +126,18 @@ static inline void platform_do_lowpower(unsigned int cpu, int *spurious) */ void exynos_cpu_power_down(int cpu) { + if (cpu == 0 && (of_machine_is_compatible("samsung,exynos5420") || + of_machine_is_compatible("samsung,exynos5800"))) { + /* + * Bypass power down for CPU0 during suspend. Check for + * the SYS_PWR_REG value to decide if we are suspending + * the system. + */ + int val = pmu_raw_readl(EXYNOS5_ARM_CORE0_SYS_PWR_REG); + + if (!(val & S5P_CORE_LOCAL_PWR_EN)) + return; + } pmu_raw_writel(0, EXYNOS_ARM_CORE_CONFIGURATION(cpu)); } diff --git a/arch/arm/mach-exynos/suspend.c b/arch/arm/mach-exynos/suspend.c index 8cef614..cc8d237 100644 --- a/arch/arm/mach-exynos/suspend.c +++ b/arch/arm/mach-exynos/suspend.c @@ -24,6 +24,7 @@ #include <asm/cacheflush.h> #include <asm/hardware/cache-l2x0.h> #include <asm/firmware.h> +#include <asm/mcpm.h> #include <asm/smp_scu.h> #include <asm/suspend.h> @@ -72,6 +73,7 @@ struct exynos_pm_data { unsigned int *release_ret_regs; void (*pm_prepare)(void); + void (*pm_resume_prepare)(void); void (*pm_resume)(void); int (*pm_suspend)(void); int (*cpu_suspend)(unsigned long); @@ -172,9 +174,28 @@ static int exynos_cpu_suspend(unsigned long arg) static int exynos5420_cpu_suspend(unsigned long arg) { - exynos_flush_cache_all(); + /* MCPM works with HW CPU identifiers */ + unsigned int mpidr = read_cpuid_mpidr(); + unsigned int cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1); + unsigned int cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0); + __raw_writel(0x0, sysram_base_addr + EXYNOS5420_CPU_STATE); - return exynos_cpu_do_idle(); + + if (IS_ENABLED(CONFIG_EXYNOS5420_MCPM)) { + mcpm_set_entry_vector(cpu, cluster, exynos_cpu_resume); + + /* + * Residency value passed to mcpm_cpu_suspend back-end + * has to be given clear semantics. Set to 0 as a + * temporary value. + */ + mcpm_cpu_suspend(0); + } + + pr_info("Failed to suspend the system\n"); + + /* return value != 0 means failure */ + return 1; } static void exynos_pm_set_wakeup_mask(void) @@ -189,9 +210,6 @@ static void exynos_pm_enter_sleep_mode(void) /* Set value of power down register for sleep mode */ exynos_sys_powerdown_conf(SYS_SLEEP); pmu_raw_writel(S5P_CHECK_SLEEP, S5P_INFORM1); - - /* ensure at least INFORM0 has the resume address */ - pmu_raw_writel(virt_to_phys(exynos_cpu_resume), S5P_INFORM0); } static void exynos_pm_prepare(void) @@ -206,6 +224,9 @@ static void exynos_pm_prepare(void) pm_data->num_extra_save); exynos_pm_enter_sleep_mode(); + + /* ensure at least INFORM0 has the resume address */ + pmu_raw_writel(virt_to_phys(exynos_cpu_resume), S5P_INFORM0); } static void exynos5420_pm_prepare(void) @@ -230,6 +251,10 @@ static void exynos5420_pm_prepare(void) exynos_pm_enter_sleep_mode(); + /* ensure at least INFORM0 has the resume address */ + if (IS_ENABLED(CONFIG_EXYNOS5420_MCPM)) + pmu_raw_writel(virt_to_phys(mcpm_entry_point), S5P_INFORM0); + tmp = pmu_raw_readl(EXYNOS5_ARM_L2_OPTION); tmp &= ~EXYNOS5_USE_RETENTION; pmu_raw_writel(tmp, EXYNOS5_ARM_L2_OPTION); @@ -318,10 +343,21 @@ early_wakeup: pmu_raw_writel(0x0, S5P_INFORM1); } +static void exynos5420_prepare_pm_resume(void) +{ + if (IS_ENABLED(CONFIG_EXYNOS5420_MCPM)) + WARN_ON(mcpm_cpu_powered_up()); +} + static void exynos5420_pm_resume(void) { unsigned long tmp; + /* Restore the CPU0 low power state register */ + tmp = pmu_raw_readl(EXYNOS5_ARM_CORE0_SYS_PWR_REG); + pmu_raw_writel(tmp | S5P_CORE_LOCAL_PWR_EN, + EXYNOS5_ARM_CORE0_SYS_PWR_REG); + /* Restore the sysram cpu state register */ __raw_writel(exynos5420_cpu_state, sysram_base_addr + EXYNOS5420_CPU_STATE); @@ -391,6 +427,8 @@ static int exynos_suspend_enter(suspend_state_t state) if (ret) return ret; + if (pm_data->pm_resume_prepare) + pm_data->pm_resume_prepare(); s3c_pm_restore_uarts(); S3C_PMDBG("%s: wakeup stat: %08x\n", __func__, @@ -448,6 +486,7 @@ static struct exynos_pm_data exynos5420_pm_data = { .wkup_irq = exynos5250_wkup_irq, .wake_disable_mask = (0x7F << 7) | (0x1F << 1), .release_ret_regs = exynos5420_release_ret_regs, + .pm_resume_prepare = exynos5420_prepare_pm_resume, .pm_resume = exynos5420_pm_resume, .pm_suspend = exynos5420_pm_suspend, .pm_prepare = exynos5420_pm_prepare, -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html