Merge with ARM SMP tree (be6eb9b7) · Commits · 戴 / test

arch/arm/Kconfig

+1 −1

Original line number	Diff line number	Diff line
		@@ -358,7 +358,7 @@ config HOTPLUG_CPU

		config LOCAL_TIMERS
		bool "Use local timer interrupts"
		depends on SMP && n
		depends on SMP && REALVIEW_MPCORE
		default y
		help
		Enable support for local timers on SMP platforms, rather then the

arch/arm/mach-realview/Makefile

+2 −0

Original line number	Diff line number	Diff line
		@@ -5,3 +5,5 @@
		obj-y := core.o clock.o
		obj-$(CONFIG_MACH_REALVIEW_EB) += realview_eb.o
		obj-$(CONFIG_SMP) += platsmp.o headsmp.o
		obj-$(CONFIG_HOTPLUG_CPU) += hotplug.o
		obj-$(CONFIG_LOCAL_TIMERS) += localtimer.o

arch/arm/mach-realview/core.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -550,7 +550,7 @@ static irqreturn_t realview_timer_interrupt(int irq, void *dev_id, struct pt_reg

		timer_tick(regs);

		#ifdef CONFIG_SMP
		#if defined(CONFIG_SMP) && !defined(CONFIG_LOCAL_TIMERS)
		smp_send_timer();
		update_process_times(user_mode(regs));
		#endif

arch/arm/mach-realview/hotplug.c

0 → 100644

+138 −0

Original line number	Diff line number	Diff line
		/*
		* 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/completion.h>

		extern volatile int pen_release;

		static DECLARE_COMPLETION(cpu_killed);

		static inline void cpu_enter_lowpower(void)
		{
		unsigned int v;

		asm volatile( "mcr p15, 0, %1, c7, c14, 0\n"
		" mcr p15, 0, %1, c7, c5, 0\n"
		" mcr p15, 0, %1, c7, c10, 4\n"
		/*
		* Turn off coherency
		*/
		" mrc p15, 0, %0, c1, c0, 1\n"
		" bic %0, %0, #0x20\n"
		" mcr p15, 0, %0, c1, c0, 1\n"
		" mrc p15, 0, %0, c1, c0, 0\n"
		" bic %0, %0, #0x04\n"
		" mcr p15, 0, %0, c1, c0, 0\n"
		: "=&r" (v)
		: "r" (0)
		: "cc");
		}

		static inline void cpu_leave_lowpower(void)
		{
		unsigned int v;

		asm volatile( "mrc p15, 0, %0, c1, c0, 0\n"
		" orr %0, %0, #0x04\n"
		" mcr p15, 0, %0, c1, c0, 0\n"
		" mrc p15, 0, %0, c1, c0, 1\n"
		" orr %0, %0, #0x20\n"
		" mcr p15, 0, %0, c1, c0, 1\n"
		: "=&r" (v)
		:
		: "cc");
		}

		static inline void platform_do_lowpower(unsigned int cpu)
		{
		/*
		* there is no power-control hardware on this platform, so all
		* we can do is put the core into WFI; this is safe as the calling
		* code will have already disabled interrupts
		*/
		for (;;) {
		/*
		* here's the WFI
		*/
		asm(".word 0xe320f003\n"
		:
		:
		: "memory", "cc");

		if (pen_release == cpu) {
		/*
		* 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
		*
		* The trouble is, letting people know about this is not really
		* possible, since we are currently running incoherently, and
		* therefore cannot safely call printk() or anything else
		*/
		#ifdef DEBUG
		printk("CPU%u: spurious wakeup call\n", cpu);
		#endif
		}
		}

		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);

		/*
		* we're ready for shutdown now, so do it
		*/
		cpu_enter_lowpower();
		platform_do_lowpower(cpu);

		/*
		* bring this CPU back into the world of cache
		* coherency, and then restore interrupts
		*/
		cpu_leave_lowpower();
		}

		int mach_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;
		}

arch/arm/mach-realview/localtimer.c

0 → 100644

+130 −0

Original line number	Diff line number	Diff line
		/*
		* linux/arch/arm/mach-realview/localtimer.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/init.h>
		#include <linux/kernel.h>
		#include <linux/delay.h>
		#include <linux/device.h>
		#include <linux/smp.h>

		#include <asm/mach/time.h>
		#include <asm/hardware/arm_twd.h>
		#include <asm/hardware/gic.h>
		#include <asm/hardware.h>
		#include <asm/io.h>
		#include <asm/irq.h>

		#include "core.h"

		#define TWD_BASE(cpu) (__io_address(REALVIEW_TWD_BASE) + \
		((cpu) * REALVIEW_TWD_SIZE))

		static unsigned long mpcore_timer_rate;

		/*
		* local_timer_ack: checks for a local timer interrupt.
		*
		* If a local timer interrupt has occured, acknowledge and return 1.
		* Otherwise, return 0.
		*/
		int local_timer_ack(void)
		{
		void __iomem *base = TWD_BASE(smp_processor_id());

		if (__raw_readl(base + TWD_TIMER_INTSTAT)) {
		__raw_writel(1, base + TWD_TIMER_INTSTAT);
		return 1;
		}

		return 0;
		}

		void __cpuinit local_timer_setup(unsigned int cpu)
		{
		void __iomem *base = TWD_BASE(cpu);
		unsigned int load, offset;
		u64 waitjiffies;
		unsigned int count;

		/*
		* If this is the first time round, we need to work out how fast
		* the timer ticks
		*/
		if (mpcore_timer_rate == 0) {
		printk("Calibrating local timer... ");

		/* Wait for a tick to start */
		waitjiffies = get_jiffies_64() + 1;

		while (get_jiffies_64() < waitjiffies)
		udelay(10);

		/* OK, now the tick has started, let's get the timer going */
		waitjiffies += 5;

		/* enable, no interrupt or reload */
		__raw_writel(0x1, base + TWD_TIMER_CONTROL);

		/* maximum value */
		__raw_writel(0xFFFFFFFFU, base + TWD_TIMER_COUNTER);

		while (get_jiffies_64() < waitjiffies)
		udelay(10);

		count = __raw_readl(base + TWD_TIMER_COUNTER);

		mpcore_timer_rate = (0xFFFFFFFFU - count) * (HZ / 5);

		printk("%lu.%02luMHz.\n", mpcore_timer_rate / 1000000,
		(mpcore_timer_rate / 100000) % 100);
		}

		load = mpcore_timer_rate / HZ;

		__raw_writel(load, base + TWD_TIMER_LOAD);
		__raw_writel(0x7, base + TWD_TIMER_CONTROL);

		/*
		* Now maneuver our local tick into the right part of the jiffy.
		* Start by working out where within the tick our local timer
		* interrupt should go.
		*/
		offset = ((mpcore_timer_rate / HZ) / (NR_CPUS + 1)) * (cpu + 1);

		/*
		* gettimeoffset() will return a number of us since the last tick.
		* Convert this number of us to a local timer tick count.
		* Be careful of integer overflow whilst keeping maximum precision.
		*
		* with HZ=100 and 1MHz (fpga) ~ 1GHz processor:
		* load = 1 ~ 10,000
		* mpcore_timer_rate/10000 = 100 ~ 100,000
		*
		* so the multiply value will be less than 10^9 always.
		*/
		load = (system_timer->offset() * (mpcore_timer_rate / 10000)) / 100;

		/* Add on our offset to get the load value */
		load = (load + offset) % (mpcore_timer_rate / HZ);

		__raw_writel(load, base + TWD_TIMER_COUNTER);

		/* Make sure our local interrupt controller has this enabled */
		__raw_writel(1 << IRQ_LOCALTIMER,
		__io_address(REALVIEW_GIC_DIST_BASE) + GIC_DIST_ENABLE_SET);
		}

		/*
		* take a local timer down
		*/
		void __cpuexit local_timer_stop(unsigned int cpu)
		{
		__raw_writel(0, TWD_BASE(cpu) + TWD_TIMER_CONTROL);
		}

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