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Commit 6f0b7c0c authored by Krzysztof Kozlowski's avatar Krzysztof Kozlowski Committed by Kukjin Kim
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ARM: EXYNOS: Move code from hotplug.c to platsmp.c 



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. 75ad2ab2 "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: default avatarKrzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: default avatarTomasz Figa <t.figa@samsung.com>
Signed-off-by: default avatarKukjin Kim <kgene.kim@samsung.com>
parent f114040e

arch/arm/mach-exynos/Makefile

+0 −3
Original line number Diff line number Diff line
@@ -16,9 +16,6 @@ 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)

arch/arm/mach-exynos/common.h

+0 −2
Original line number Diff line number Diff line
@@ -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)

arch/arm/mach-exynos/hotplug.c

deleted100644 → 0
+0 −91
Original line number Diff line number Diff line 
/*

 *  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);

}

arch/arm/mach-exynos/platsmp.c

+74 −0
Original line number Diff line number Diff line
@@ -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,