From e2e54362d9c8c1e8d52ff576a4e0f6e61f569356 Mon Sep 17 00:00:00 2001 From: Chander Kashyap Date: Sat, 5 Jul 2014 06:24:34 +0900 Subject: [PATCH 1/6] cpuidle: big.LITTLE: add of_device_id structure This driver will be used by many big.Little Soc's. As of now it does string matching of hardcoded compatible string to init the driver. This comparison list will keep on growing with addition of new SoC's. Hence add of_device_id structure to collect the compatible strings of SoC's using this driver. Signed-off-by: Chander Kashyap Reviewed-by: Tomasz Figa Acked-by: Daniel Lezcano Signed-off-by: Kukjin Kim --- drivers/cpuidle/cpuidle-big_little.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/drivers/cpuidle/cpuidle-big_little.c b/drivers/cpuidle/cpuidle-big_little.c index b45fc6249041b..4cd02bd2e3ba8 100644 --- a/drivers/cpuidle/cpuidle-big_little.c +++ b/drivers/cpuidle/cpuidle-big_little.c @@ -163,14 +163,23 @@ static int __init bl_idle_driver_init(struct cpuidle_driver *drv, int cpu_id) return 0; } +static const struct of_device_id compatible_machine_match[] = { + { .compatible = "arm,vexpress,v2p-ca15_a7" }, + {}, +}; + static int __init bl_idle_init(void) { int ret; + struct device_node *root = of_find_node_by_path("/"); + + if (!root) + return -ENODEV; /* * Initialize the driver just for a compliant set of machines */ - if (!of_machine_is_compatible("arm,vexpress,v2p-ca15_a7")) + if (!of_match_node(compatible_machine_match, root)) return -ENODEV; /* * For now the differentiation between little and big cores From 6ec4f8d0d91f2067870ce948fcd505620d0d2987 Mon Sep 17 00:00:00 2001 From: Chander Kashyap Date: Sat, 5 Jul 2014 06:24:35 +0900 Subject: [PATCH 2/6] ARM: EXYNOS: add generic function to calculate cpu number The address of cpu power registers in pmu is based on cpu number offsets. This function calculate the same. This is essentially required in case of multi-cluster SoC's e.g Exynos5420. Signed-off-by: Chander Kashyap Reviewed-by: Tomasz Figa Signed-off-by: Kukjin Kim --- arch/arm/mach-exynos/regs-pmu.h | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/arch/arm/mach-exynos/regs-pmu.h b/arch/arm/mach-exynos/regs-pmu.h index 1d13b08708f00..aff23bd395e69 100644 --- a/arch/arm/mach-exynos/regs-pmu.h +++ b/arch/arm/mach-exynos/regs-pmu.h @@ -323,4 +323,13 @@ #define EXYNOS5420_SWRESET_KFC_SEL 0x3 +#include +#define MAX_CPUS_IN_CLUSTER 4 + +static inline unsigned int exynos_pmu_cpunr(unsigned int mpidr) +{ + return ((MPIDR_AFFINITY_LEVEL(mpidr, 1) * MAX_CPUS_IN_CLUSTER) + + MPIDR_AFFINITY_LEVEL(mpidr, 0)); +} + #endif /* __ASM_ARCH_REGS_PMU_H */ From 2aaafcdb68830cb849a08e0ff57f7ca1cffde57d Mon Sep 17 00:00:00 2001 From: Chander Kashyap Date: Sat, 5 Jul 2014 06:24:35 +0900 Subject: [PATCH 3/6] cpuidle: big.LITTLE: Add ARCH_EXYNOS entry in config Add support to select generic big-little cpuidle driver for Samsung Exynos series SoC's. This is required for Exynos big-llittle SoC's eg, Exynos5420. Signed-off-by: Chander Kashyap Reviewed-by: Tomasz Figa Acked-by: Daniel Lezcano Signed-off-by: Kukjin Kim --- drivers/cpuidle/Kconfig.arm | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/cpuidle/Kconfig.arm b/drivers/cpuidle/Kconfig.arm index b6d69e899f5de..2f6b33ea6e089 100644 --- a/drivers/cpuidle/Kconfig.arm +++ b/drivers/cpuidle/Kconfig.arm @@ -9,7 +9,7 @@ config ARM_ARMADA_370_XP_CPUIDLE config ARM_BIG_LITTLE_CPUIDLE bool "Support for ARM big.LITTLE processors" - depends on ARCH_VEXPRESS_TC2_PM + depends on ARCH_VEXPRESS_TC2_PM || ARCH_EXYNOS select ARM_CPU_SUSPEND select CPU_IDLE_MULTIPLE_DRIVERS help From 64a3c4caa91c72a00ba2e464a0b2a0a5ce7a312b Mon Sep 17 00:00:00 2001 From: Chander Kashyap Date: Sat, 5 Jul 2014 06:24:35 +0900 Subject: [PATCH 4/6] cpuidle: big.LITTLE: init driver for exynos5420 Add "samsung,exynos5420" compatible string to initialize generic big-little cpuidle driver for Exynos5420. Signed-off-by: Chander Kashyap Reviewed-by: Tomasz Figa Acked-by: Daniel Lezcano Signed-off-by: Kukjin Kim --- drivers/cpuidle/cpuidle-big_little.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/cpuidle/cpuidle-big_little.c b/drivers/cpuidle/cpuidle-big_little.c index 4cd02bd2e3ba8..344d79fa34078 100644 --- a/drivers/cpuidle/cpuidle-big_little.c +++ b/drivers/cpuidle/cpuidle-big_little.c @@ -165,6 +165,7 @@ static int __init bl_idle_driver_init(struct cpuidle_driver *drv, int cpu_id) static const struct of_device_id compatible_machine_match[] = { { .compatible = "arm,vexpress,v2p-ca15_a7" }, + { .compatible = "samsung,exynos5420" }, {}, }; From b5a296cdf43e86e189c17537b85c6c0168aae750 Mon Sep 17 00:00:00 2001 From: Chander Kashyap Date: Sat, 5 Jul 2014 06:24:35 +0900 Subject: [PATCH 5/6] ARM: EXYNOS: do not allow cpuidle registration for exynos5420 Exynos5420 is big.Little Soc. It uses cpuidle-big-litle generic cpuidle driver. Hence do not allow exynos cpuidle driver registration for Exynos5420. Signed-off-by: Chander Kashyap Reviewed-by: Tomasz Figa Acked-by: Daniel Lezcano Signed-off-by: Kukjin Kim --- arch/arm/mach-exynos/exynos.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/arch/arm/mach-exynos/exynos.c b/arch/arm/mach-exynos/exynos.c index 46d893fcbe853..c7d960aa95a8f 100644 --- a/arch/arm/mach-exynos/exynos.c +++ b/arch/arm/mach-exynos/exynos.c @@ -298,7 +298,9 @@ static void __init exynos_dt_machine_init(void) if (!IS_ENABLED(CONFIG_SMP)) exynos_sysram_init(); - exynos_cpuidle_init(); + if (!of_machine_is_compatible("samsung,exynos5420")) + exynos_cpuidle_init(); + exynos_cpufreq_init(); of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL); From fc2cac41ebbfb16da8b036cba6ec6714ab780a6d Mon Sep 17 00:00:00 2001 From: Chander Kashyap Date: Sat, 5 Jul 2014 06:24:35 +0900 Subject: [PATCH 6/6] ARM: EXYNOS: populate suspend and powered_up callbacks for mcpm In order to support cpuidle through mcpm, suspend and powered-up callbacks are required in mcpm platform code. Hence populate the same callbacks. Signed-off-by: Chander Kashyap Signed-off-by: Chander Kashyap Reviewed-by: Tomasz Figa Signed-off-by: Kukjin Kim --- arch/arm/mach-exynos/mcpm-exynos.c | 36 ++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+) diff --git a/arch/arm/mach-exynos/mcpm-exynos.c b/arch/arm/mach-exynos/mcpm-exynos.c index ace0ed617476e..13a210865c6f0 100644 --- a/arch/arm/mach-exynos/mcpm-exynos.c +++ b/arch/arm/mach-exynos/mcpm-exynos.c @@ -257,10 +257,46 @@ static int exynos_wait_for_powerdown(unsigned int cpu, unsigned int cluster) return -ETIMEDOUT; /* timeout */ } +static void exynos_powered_up(void) +{ + unsigned int mpidr, cpu, cluster; + + mpidr = read_cpuid_mpidr(); + cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0); + cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1); + + arch_spin_lock(&exynos_mcpm_lock); + if (cpu_use_count[cpu][cluster] == 0) + cpu_use_count[cpu][cluster] = 1; + arch_spin_unlock(&exynos_mcpm_lock); +} + +static void exynos_suspend(u64 residency) +{ + unsigned int mpidr, cpunr; + + exynos_power_down(); + + /* + * Execution reaches here only if cpu did not power down. + * Hence roll back the changes done in exynos_power_down function. + * + * CAUTION: "This function requires the stack data to be visible through + * power down and can only be executed on processors like A15 and A7 + * that hit the cache with the C bit clear in the SCTLR register." + */ + mpidr = read_cpuid_mpidr(); + cpunr = exynos_pmu_cpunr(mpidr); + + exynos_cpu_power_up(cpunr); +} + static const struct mcpm_platform_ops exynos_power_ops = { .power_up = exynos_power_up, .power_down = exynos_power_down, .wait_for_powerdown = exynos_wait_for_powerdown, + .suspend = exynos_suspend, + .powered_up = exynos_powered_up, }; static void __init exynos_mcpm_usage_count_init(void)