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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. 75ad2ab28f "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@samsung.com>
Reviewed-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
This commit is contained in:
Krzysztof Kozlowski 2014-09-14 02:49:31 +09:00 committed by Kukjin Kim
parent f114040e3e
commit 6f0b7c0c6f
4 changed files with 74 additions and 96 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
arch/arm/mach-exynos/Makefile
View File

@ -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)

2
arch/arm/mach-exynos/common.h
View File

@ -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)

91
arch/arm/mach-exynos/hotplug.c
View File

@ -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);
}

74
arch/arm/mach-exynos/platsmp.c
View File

@ -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,