From mboxrd@z Thu Jan 1 00:00:00 1970 From: daniel.lezcano@linaro.org (Daniel Lezcano) Date: Tue, 05 Aug 2014 16:46:10 +0200 Subject: [PATCH v5 1/3] ARM: EXYNOS: Move code from hotplug.c to platsmp.c In-Reply-To: <1407235425-13937-1-git-send-email-k.kozlowski@samsung.com> References: <1407235425-13937-1-git-send-email-k.kozlowski@samsung.com> Message-ID: <53E0EE32.7060500@linaro.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 08/05/2014 12:43 PM, Krzysztof Kozlowski wrote: > 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. Keeping this file does not > give any benefits. > > 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. What is the benefit of moving this code around ? Usually the cpu hotplug code is located in hotplug.c for most of the platforms, so why moving pm code inside platsmp ? > Signed-off-by: Krzysztof Kozlowski > Reviewed-by: Tomasz Figa > > --- > 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 > -#include > -#include > -#include > - > -#include > -#include > -#include > - > -#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 > > #include > +#include > #include > #include > #include > @@ -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, > -- Linaro.org ? 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