[PATCH v5 RESEND 1/3] ARM: EXYNOS: Move code from hotplug.c to platsmp.c
Krzysztof Kozlowski
k.kozlowski at samsung.com
Fri Sep 5 05:34:53 PDT 2014
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.
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 at samsung.com>
Reviewed-by: Tomasz Figa <t.figa at samsung.com>
---
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 <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);
-}
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 <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,
--
1.9.1
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