ARM: 6391/1: ux500: add CPU hotplug support (9d704c04) · Commits · e / devices / android_kernel_xiaomi_markw

arch/arm/mach-ux500/Makefile

+1 −0

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		@@ -8,4 +8,5 @@ obj-$(CONFIG_UX500_SOC_DB8500) += cpu-db8500.o devices-db8500.o prcmu.o
		obj-$(CONFIG_MACH_U8500_MOP) += board-mop500.o board-mop500-sdi.o
		obj-$(CONFIG_MACH_U5500) += board-u5500.o
		obj-$(CONFIG_SMP) += platsmp.o headsmp.o
		obj-$(CONFIG_HOTPLUG_CPU) += hotplug.o
		obj-$(CONFIG_LOCAL_TIMERS) += localtimer.o

0 → 100644

+75 −0

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		/*
		* Copyright (C) STMicroelectronics 2009
		* Copyright (C) ST-Ericsson SA 2010
		*
		* License Terms: GNU General Public License v2
		* Based on ARM realview platform
		*
		* Author: Sundar Iyer <sundar.iyer@stericsson.com>
		*
		*/
		#include <linux/kernel.h>
		#include <linux/errno.h>
		#include <linux/smp.h>
		#include <linux/completion.h>

		#include <asm/cacheflush.h>

		extern volatile int pen_release;

		static DECLARE_COMPLETION(cpu_killed);

		static inline void platform_do_lowpower(unsigned int cpu)
		{
		flush_cache_all();

		/* we put the platform to just WFI */
		for (;;) {
		__asm__ __volatile__("dsb\n\t" "wfi\n\t"
		: : : "memory");
		if (pen_release == cpu) {
		/*
		* OK, proper wakeup, we're done
		*/
		break;
		}
		}
		}

		int platform_cpu_kill(unsigned int cpu)
		{
		return wait_for_completion_timeout(&cpu_killed, 5000);
		}

		/*
		* platform-specific code to shutdown a CPU
		*
		* Called with IRQs disabled
		*/
		void platform_cpu_die(unsigned int cpu)
		{
		#ifdef DEBUG
		unsigned int this_cpu = hard_smp_processor_id();

		if (cpu != this_cpu) {
		printk(KERN_CRIT "Eek! platform_cpu_die running on %u, should be %u\n",
		this_cpu, cpu);
		BUG();
		}
		#endif

		printk(KERN_NOTICE "CPU%u: shutdown\n", cpu);
		complete(&cpu_killed);

		/* directly enter low power state, skipping secure registers */
		platform_do_lowpower(cpu);
		}

		int platform_cpu_disable(unsigned int cpu)
		{
		/*
		* we don't allow CPU 0 to be shutdown (it is still too special
		* e.g. clock tick interrupts)
		*/
		return cpu == 0 ? -EPERM : 0;
		}

+2 −0

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		@@ -78,6 +78,8 @@ int __cpuinit boot_secondary(unsigned int cpu, struct task_struct *idle)
		__cpuc_flush_dcache_area((void *)&pen_release, sizeof(pen_release));
		outer_clean_range(__pa(&pen_release), __pa(&pen_release) + 1);

		smp_cross_call(cpumask_of(cpu));

		timeout = jiffies + (1 * HZ);
		while (time_before(jiffies, timeout)) {
		if (pen_release == -1)