[PATCH 8/8] ARM: smp: Remove local timer API

From: Stephen Boyd
Date: Fri Feb 22 2013 - 02:28:20 EST


There are no more users of this API, remove it.

Cc: Russell King <linux@xxxxxxxxxxxxxxxx>
Signed-off-by: Stephen Boyd <sboyd@xxxxxxxxxxxxxx>
---
arch/arm/Kconfig | 12 +------
arch/arm/include/asm/localtimer.h | 34 --------------------
arch/arm/kernel/smp.c | 67 ++++++---------------------------------
arch/arm/mach-omap2/Kconfig | 1 -
arch/arm/mach-omap2/timer.c | 7 ----
5 files changed, 11 insertions(+), 110 deletions(-)
delete mode 100644 arch/arm/include/asm/localtimer.h

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index dedf02b..7d4338d 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1527,6 +1527,7 @@ config SMP
depends on HAVE_SMP
depends on MMU
select HAVE_ARM_SCU if !ARCH_MSM_SCORPIONMP
+ select HAVE_ARM_TWD if (!ARCH_MSM_SCORPIONMP && !EXYNOS4_MCT)
select USE_GENERIC_SMP_HELPERS
help
This enables support for systems with more than one CPU. If you have
@@ -1646,17 +1647,6 @@ config ARM_PSCI
0022A ("Power State Coordination Interface System Software on
ARM processors").

-config LOCAL_TIMERS
- bool "Use local timer interrupts"
- depends on SMP
- default y
- select HAVE_ARM_TWD if (!ARCH_MSM_SCORPIONMP && !EXYNOS4_MCT)
- help
- Enable support for local timers on SMP platforms, rather then the
- legacy IPI broadcast method. Local timers allows the system
- accounting to be spread across the timer interval, preventing a
- "thundering herd" at every timer tick.
-
config ARCH_NR_GPIO
int
default 1024 if ARCH_SHMOBILE || ARCH_TEGRA
diff --git a/arch/arm/include/asm/localtimer.h b/arch/arm/include/asm/localtimer.h
deleted file mode 100644
index f77ffc1..0000000
--- a/arch/arm/include/asm/localtimer.h
+++ /dev/null
@@ -1,34 +0,0 @@
-/*
- * arch/arm/include/asm/localtimer.h
- *
- * Copyright (C) 2004-2005 ARM Ltd.
- *
- * 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.
- */
-#ifndef __ASM_ARM_LOCALTIMER_H
-#define __ASM_ARM_LOCALTIMER_H
-
-#include <linux/errno.h>
-
-struct clock_event_device;
-
-struct local_timer_ops {
- int (*setup)(struct clock_event_device *);
- void (*stop)(struct clock_event_device *);
-};
-
-#ifdef CONFIG_LOCAL_TIMERS
-/*
- * Register a local timer driver
- */
-int local_timer_register(struct local_timer_ops *);
-#else
-static inline int local_timer_register(struct local_timer_ops *ops)
-{
- return -ENXIO;
-}
-#endif
-
-#endif
diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c
index 2d5197d..f628c79 100644
--- a/arch/arm/kernel/smp.c
+++ b/arch/arm/kernel/smp.c
@@ -41,7 +41,6 @@
#include <asm/sections.h>
#include <asm/tlbflush.h>
#include <asm/ptrace.h>
-#include <asm/localtimer.h>
#include <asm/smp_plat.h>
#include <asm/virt.h>
#include <asm/mach/arch.h>
@@ -133,8 +132,6 @@ int __cpuinit boot_secondary(unsigned int cpu, struct task_struct *idle)
}

#ifdef CONFIG_HOTPLUG_CPU
-static void percpu_timer_stop(void);
-
static int platform_cpu_kill(unsigned int cpu)
{
if (smp_ops.cpu_kill)
@@ -178,11 +175,6 @@ int __cpuinit __cpu_disable(void)
migrate_irqs();

/*
- * Stop the local timer for this CPU.
- */
- percpu_timer_stop();
-
- /*
* Flush user cache and TLB mappings, and then remove this CPU
* from the vm mask set of all processes.
*
@@ -269,7 +261,7 @@ static void __cpuinit smp_store_cpu_info(unsigned int cpuid)
store_cpu_topology(cpuid);
}

-static void percpu_timer_setup(void);
+static void broadcast_timer_setup(void);

/*
* This is the secondary CPU boot entry. We're using this CPUs
@@ -325,9 +317,9 @@ asmlinkage void __cpuinit secondary_start_kernel(void)
complete(&cpu_running);

/*
- * Setup the percpu timer for this CPU.
+ * Setup the dummy broadcast timer for this CPU.
*/
- percpu_timer_setup();
+ broadcast_timer_setup();

local_irq_enable();
local_fiq_enable();
@@ -375,10 +367,10 @@ void __init smp_prepare_cpus(unsigned int max_cpus)
max_cpus = ncores;
if (ncores > 1 && max_cpus) {
/*
- * Enable the local timer or broadcast device for the
+ * Enable the dummy broadcast device for the
* boot CPU, but only if we have more than one CPU.
*/
- percpu_timer_setup();
+ broadcast_timer_setup();

/*
* Initialise the present map, which describes the set of CPUs
@@ -473,8 +465,12 @@ static void broadcast_timer_set_mode(enum clock_event_mode mode,
{
}

-static void __cpuinit broadcast_timer_setup(struct clock_event_device *evt)
+static void __cpuinit broadcast_timer_setup(void)
{
+ unsigned int cpu = smp_processor_id();
+ struct clock_event_device *evt = &per_cpu(percpu_clockevent, cpu);
+
+ evt->cpumask = cpumask_of(cpu);
evt->name = "dummy_timer";
evt->features = CLOCK_EVT_FEAT_ONESHOT |
CLOCK_EVT_FEAT_PERIODIC |
@@ -486,49 +482,6 @@ static void __cpuinit broadcast_timer_setup(struct clock_event_device *evt)
clockevents_register_device(evt);
}

-static struct local_timer_ops *lt_ops;
-
-#ifdef CONFIG_LOCAL_TIMERS
-int local_timer_register(struct local_timer_ops *ops)
-{
- if (!is_smp() || !setup_max_cpus)
- return -ENXIO;
-
- if (lt_ops)
- return -EBUSY;
-
- lt_ops = ops;
- return 0;
-}
-#endif
-
-static void __cpuinit percpu_timer_setup(void)
-{
- unsigned int cpu = smp_processor_id();
- struct clock_event_device *evt = &per_cpu(percpu_clockevent, cpu);
-
- evt->cpumask = cpumask_of(cpu);
-
- if (!lt_ops || lt_ops->setup(evt))
- broadcast_timer_setup(evt);
-}
-
-#ifdef CONFIG_HOTPLUG_CPU
-/*
- * The generic clock events code purposely does not stop the local timer
- * on CPU_DEAD/CPU_DEAD_FROZEN hotplug events, so we have to do it
- * manually here.
- */
-static void percpu_timer_stop(void)
-{
- unsigned int cpu = smp_processor_id();
- struct clock_event_device *evt = &per_cpu(percpu_clockevent, cpu);
-
- if (lt_ops)
- lt_ops->stop(evt);
-}
-#endif
-
static DEFINE_RAW_SPINLOCK(stop_lock);

/*
diff --git a/arch/arm/mach-omap2/Kconfig b/arch/arm/mach-omap2/Kconfig
index 49ac3df..6e1f871 100644
--- a/arch/arm/mach-omap2/Kconfig
+++ b/arch/arm/mach-omap2/Kconfig
@@ -88,7 +88,6 @@ config ARCH_OMAP4
select CACHE_L2X0
select CPU_V7
select HAVE_SMP
- select LOCAL_TIMERS if SMP
select OMAP_INTERCONNECT
select PL310_ERRATA_588369
select PL310_ERRATA_727915
diff --git a/arch/arm/mach-omap2/timer.c b/arch/arm/mach-omap2/timer.c
index 2bdd4cf..c00a8f8 100644
--- a/arch/arm/mach-omap2/timer.c
+++ b/arch/arm/mach-omap2/timer.c
@@ -587,7 +587,6 @@ OMAP_SYS_GP_TIMER_INIT(3_am33xx, 1, OMAP4_MPU_SOURCE, "ti,timer-alwon",
#ifdef CONFIG_ARCH_OMAP4
OMAP_SYS_32K_TIMER_INIT(4, 1, OMAP4_32K_SOURCE, "ti,timer-alwon",
2, OMAP4_MPU_SOURCE);
-#ifdef CONFIG_LOCAL_TIMERS
static DEFINE_TWD_LOCAL_TIMER(twd_local_timer, OMAP44XX_LOCAL_TWD_BASE, 29);
void __init omap4_local_timer_init(void)
{
@@ -606,12 +605,6 @@ void __init omap4_local_timer_init(void)
pr_err("twd_local_timer_register failed %d\n", err);
}
}
-#else /* CONFIG_LOCAL_TIMERS */
-void __init omap4_local_timer_init(void)
-{
- omap4_sync32k_timer_init();
-}
-#endif /* CONFIG_LOCAL_TIMERS */
#endif /* CONFIG_ARCH_OMAP4 */

#ifdef CONFIG_SOC_OMAP5
--
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