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> --- 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. This has been tested both on an SMDK5420 and Peach Pit Chromebook on next-20140704. Nicolas' boot cluster CCI enablement patches are in linux-next now. Here are the dependencies (some of these patches did not apply cleanly): 1) Cleanup patches for mach-exynos http://comments.gmane.org/gmane.linux.kernel.samsung-soc/33772 2) PMU cleanup and refactoring for using DT https://www.mail-archive.com/linux-kernel@xxxxxxxxxxxxxxx/msg671625.html 3) Exynos5420 PMU/S2R Series http://comments.gmane.org/gmane.linux.kernel.samsung-soc/33898 4) Exynos5420 CPUIdle Series which populates MCPM suspend/powered_up call-backs. www.gossamer-threads.com/lists/linux/kernel/1945347 https://patchwork.kernel.org/patch/4357461/ 5) Exynos5420 MCPM cluster power down support http://www.spinics.net/lists/arm-kernel/msg339988.html 6) TPM reset mask patch http://www.spinics.net/lists/arm-kernel/msg341884.html arch/arm/mach-exynos/mcpm-exynos.c | 32 +++++++++++++++------- arch/arm/mach-exynos/pm.c | 54 ++++++++++++++++++++++++++++++++++++-- 2 files changed, 74 insertions(+), 12 deletions(-) diff --git a/arch/arm/mach-exynos/mcpm-exynos.c b/arch/arm/mach-exynos/mcpm-exynos.c index 2dd51cc..74ad772 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 @@ -319,10 +322,26 @@ 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; @@ -389,16 +408,9 @@ static int __init exynos_mcpm_init(void) __raw_writel(value, pmu_base_addr + 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/pm.c b/arch/arm/mach-exynos/pm.c index 69cf678..e2ba1e5 100644 --- a/arch/arm/mach-exynos/pm.c +++ b/arch/arm/mach-exynos/pm.c @@ -24,6 +24,7 @@ #include <asm/cacheflush.h> #include <asm/hardware/cache-l2x0.h> +#include <asm/mcpm.h> #include <asm/smp_scu.h> #include <asm/suspend.h> @@ -123,6 +124,17 @@ static int exynos_irq_set_wake(struct irq_data *data, unsigned int state) */ void exynos_cpu_power_down(int cpu) { + if (soc_is_exynos5420() && cpu == 0) { + /* + * Bypass power down for CPU0 during suspend. Check for + * the SYS_PWR_REG value to decide if we are suspending + * the system. + */ + int val = __raw_readl(pmu_base_addr + + EXYNOS5_ARM_CORE0_SYS_PWR_REG); + if (!(val & S5P_CORE_LOCAL_PWR_EN)) + return; + } pmu_raw_writel(0, EXYNOS_ARM_CORE_CONFIGURATION(cpu)); } @@ -318,7 +330,10 @@ static void exynos_pm_prepare(void) /* ensure at least INFORM0 has the resume address */ - pmu_raw_writel(virt_to_phys(exynos_cpu_resume), S5P_INFORM0); + if (soc_is_exynos5420() && IS_ENABLED(CONFIG_MCPM)) + pmu_raw_writel(virt_to_phys(mcpm_entry_point), S5P_INFORM0); + else + pmu_raw_writel(virt_to_phys(exynos_cpu_resume), S5P_INFORM0); if (soc_is_exynos5420()) { tmp = __raw_readl(pmu_base_addr + EXYNOS5_ARM_L2_OPTION); @@ -408,6 +423,12 @@ static void exynos_pm_resume(void) unsigned int tmp; if (soc_is_exynos5420()) { + /* Restore the CPU0 low power state register */ + tmp = __raw_readl(pmu_base_addr + + 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); @@ -490,6 +511,28 @@ static struct syscore_ops exynos_pm_syscore_ops = { .resume = exynos_pm_resume, }; +static int notrace exynos_mcpm_cpu_suspend(unsigned long arg) +{ + /* 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); + + 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); + + /* return value != 0 means failure */ + return 1; +} + /* * Suspend Ops */ @@ -517,10 +560,17 @@ static int exynos_suspend_enter(suspend_state_t state) flush_cache_all(); s3c_pm_check_store(); - ret = cpu_suspend(0, exynos_cpu_suspend); + /* Use the MCPM layer to suspend 5420 which is a multi-cluster SoC */ + if (soc_is_exynos5420() && IS_ENABLED(CONFIG_MCPM)) + ret = cpu_suspend(0, exynos_mcpm_cpu_suspend); + else + ret = cpu_suspend(0, exynos_cpu_suspend); if (ret) return ret; + if (soc_is_exynos5420() && IS_ENABLED(CONFIG_MCPM)) + mcpm_cpu_powered_up(); + s3c_pm_restore_uarts(); S3C_PMDBG("%s: wakeup stat: %08x\n", __func__, -- 2.0.0 -- 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
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