Cleanup a little the SMP/hotplug code for Exynos by: 1. Moving completely all functions from hotplug.c into the platsmp.c; 2. Deleting the hotplug.c file. After recent cleanups (e.g. 75ad2ab28f0f "ARM: EXYNOS: use v7_exit_coherency_flush macro for cache disabling") there was only CPU power down related code in hotplug.c file. Rationale behind the code movement and benefits: 1. The file platsmp.c is the only user of code located in hotplug.c. Keeping code in hotplug.c required declaring exynos_cpu_die() in common.h. Such dependencies and mentioned exynos_cpu_die() declaration can be removed. 2. In next patches exynos_set_delayed_reset_assertion() will be introduced. This function will be called by: - cpu_leave_power (hotplug.c), - platform_do_lowpower (hotplug.c), - exynos_boot_secondary (platsmp.c). Merging hotplug.c into platsmp.c leads to simpler and cleaner code with less dependencies between files. The commit only moves code around with one additional observable change: the hotplug.c was compiled with custom CFLAGS (-march=armv7-a). These CFLAGS are not necessary any more. Signed-off-by: Krzysztof Kozlowski <k.kozlowski@xxxxxxxxxxx> Reviewed-by: Tomasz Figa <t.figa@xxxxxxxxxxx> --- Changes since v4: 1. Rebase on linux-next-20140804. 2. Add Reviewed-by Tomasz Figa. --- arch/arm/mach-exynos/Makefile | 3 -- arch/arm/mach-exynos/common.h | 2 - arch/arm/mach-exynos/hotplug.c | 91 ------------------------------------------ arch/arm/mach-exynos/platsmp.c | 74 ++++++++++++++++++++++++++++++++++ 4 files changed, 74 insertions(+), 96 deletions(-) delete mode 100644 arch/arm/mach-exynos/hotplug.c diff --git a/arch/arm/mach-exynos/Makefile b/arch/arm/mach-exynos/Makefile index 788f26d21141..0095de99d703 100644 --- a/arch/arm/mach-exynos/Makefile +++ b/arch/arm/mach-exynos/Makefile @@ -21,9 +21,6 @@ obj-$(CONFIG_PM_GENERIC_DOMAINS) += pm_domains.o obj-$(CONFIG_SMP) += platsmp.o headsmp.o -obj-$(CONFIG_HOTPLUG_CPU) += hotplug.o -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) diff --git a/arch/arm/mach-exynos/common.h b/arch/arm/mach-exynos/common.h index 47b904b3b973..3d3e6af9d015 100644 --- a/arch/arm/mach-exynos/common.h +++ b/arch/arm/mach-exynos/common.h @@ -130,8 +130,6 @@ extern void exynos_cpu_resume(void); extern struct smp_operations exynos_smp_ops; -extern void exynos_cpu_die(unsigned int cpu); - /* PMU(Power Management Unit) support */ #define PMU_TABLE_END (-1U) diff --git a/arch/arm/mach-exynos/hotplug.c b/arch/arm/mach-exynos/hotplug.c deleted file mode 100644 index 4d86961a7957..000000000000 --- a/arch/arm/mach-exynos/hotplug.c +++ /dev/null @@ -1,91 +0,0 @@ -/* - * Cloned from linux/arch/arm/mach-realview/hotplug.c - * - * Copyright (C) 2002 ARM Ltd. - * All Rights Reserved - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. -*/ - -#include <linux/kernel.h> -#include <linux/errno.h> -#include <linux/smp.h> -#include <linux/io.h> - -#include <asm/cacheflush.h> -#include <asm/cp15.h> -#include <asm/smp_plat.h> - -#include "common.h" -#include "regs-pmu.h" - -static inline void cpu_leave_lowpower(void) -{ - unsigned int v; - - asm volatile( - "mrc p15, 0, %0, c1, c0, 0\n" - " orr %0, %0, %1\n" - " mcr p15, 0, %0, c1, c0, 0\n" - " mrc p15, 0, %0, c1, c0, 1\n" - " orr %0, %0, %2\n" - " mcr p15, 0, %0, c1, c0, 1\n" - : "=&r" (v) - : "Ir" (CR_C), "Ir" (0x40) - : "cc"); -} - -static inline void platform_do_lowpower(unsigned int cpu, int *spurious) -{ - u32 mpidr = cpu_logical_map(cpu); - u32 core_id = MPIDR_AFFINITY_LEVEL(mpidr, 0); - - for (;;) { - - /* Turn the CPU off on next WFI instruction. */ - exynos_cpu_power_down(core_id); - - wfi(); - - if (pen_release == core_id) { - /* - * OK, proper wakeup, we're done - */ - break; - } - - /* - * Getting here, means that we have come out of WFI without - * having been woken up - this shouldn't happen - * - * Just note it happening - when we're woken, we can report - * its occurrence. - */ - (*spurious)++; - } -} - -/* - * platform-specific code to shutdown a CPU - * - * Called with IRQs disabled - */ -void __ref exynos_cpu_die(unsigned int cpu) -{ - int spurious = 0; - - v7_exit_coherency_flush(louis); - - platform_do_lowpower(cpu, &spurious); - - /* - * bring this CPU back into the world of cache - * coherency, and then restore interrupts - */ - cpu_leave_lowpower(); - - if (spurious) - pr_warn("CPU%u: %u spurious wakeup calls\n", cpu, spurious); -} diff --git a/arch/arm/mach-exynos/platsmp.c b/arch/arm/mach-exynos/platsmp.c index a9f1cf759949..a809f76c8160 100644 --- a/arch/arm/mach-exynos/platsmp.c +++ b/arch/arm/mach-exynos/platsmp.c @@ -22,6 +22,7 @@ #include <linux/of_address.h> #include <asm/cacheflush.h> +#include <asm/cp15.h> #include <asm/smp_plat.h> #include <asm/smp_scu.h> #include <asm/firmware.h> @@ -33,6 +34,54 @@ extern void exynos4_secondary_startup(void); +#ifdef CONFIG_HOTPLUG_CPU +static inline void cpu_leave_lowpower(void) +{ + unsigned int v; + + asm volatile( + "mrc p15, 0, %0, c1, c0, 0\n" + " orr %0, %0, %1\n" + " mcr p15, 0, %0, c1, c0, 0\n" + " mrc p15, 0, %0, c1, c0, 1\n" + " orr %0, %0, %2\n" + " mcr p15, 0, %0, c1, c0, 1\n" + : "=&r" (v) + : "Ir" (CR_C), "Ir" (0x40) + : "cc"); +} + +static inline void platform_do_lowpower(unsigned int cpu, int *spurious) +{ + u32 mpidr = cpu_logical_map(cpu); + u32 core_id = MPIDR_AFFINITY_LEVEL(mpidr, 0); + + for (;;) { + + /* Turn the CPU off on next WFI instruction. */ + exynos_cpu_power_down(core_id); + + wfi(); + + if (pen_release == core_id) { + /* + * OK, proper wakeup, we're done + */ + break; + } + + /* + * Getting here, means that we have come out of WFI without + * having been woken up - this shouldn't happen + * + * Just note it happening - when we're woken, we can report + * its occurrence. + */ + (*spurious)++; + } +} +#endif /* CONFIG_HOTPLUG_CPU */ + /** * exynos_core_power_down : power down the specified cpu * @cpu : the cpu to power down @@ -318,6 +367,31 @@ static void __init exynos_smp_prepare_cpus(unsigned int max_cpus) } } +#ifdef CONFIG_HOTPLUG_CPU +/* + * platform-specific code to shutdown a CPU + * + * Called with IRQs disabled + */ +static void __ref exynos_cpu_die(unsigned int cpu) +{ + int spurious = 0; + + v7_exit_coherency_flush(louis); + + platform_do_lowpower(cpu, &spurious); + + /* + * bring this CPU back into the world of cache + * coherency, and then restore interrupts + */ + cpu_leave_lowpower(); + + if (spurious) + pr_warn("CPU%u: %u spurious wakeup calls\n", cpu, spurious); +} +#endif /* CONFIG_HOTPLUG_CPU */ + struct smp_operations exynos_smp_ops __initdata = { .smp_init_cpus = exynos_smp_init_cpus, .smp_prepare_cpus = exynos_smp_prepare_cpus, -- 1.9.1 -- 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