[PATCHv7 04/11] ARM: smp_twd: Divorce smp_twd from local timer API
Stephen Boyd
sboyd at codeaurora.org
Mon Jun 3 16:33:55 EDT 2013
Separate the smp_twd timers from the local timer API. This will
allow us to remove ARM local timer support in the near future and
gets us closer to moving this driver to drivers/clocksource.
Tested-by: Mark Rutland <mark.rutland at arm.com>
Acked-by: Marc Zyngier <marc.zyngier at arm.com>,
Cc: Russell King <linux at arm.linux.org.uk>
Cc: Tony Lindgren <tony at atomide.com>
Signed-off-by: Stephen Boyd <sboyd at codeaurora.org>
---
arch/arm/Kconfig | 2 +-
arch/arm/kernel/smp_twd.c | 64 ++++++++++++++++++++++++++++--------------
arch/arm/mach-highbank/Kconfig | 2 +-
arch/arm/mach-imx/Kconfig | 2 +-
arch/arm/mach-omap2/Kconfig | 2 +-
arch/arm/mach-realview/Kconfig | 8 +++---
arch/arm/mach-spear/Kconfig | 2 +-
arch/arm/mach-tegra/Kconfig | 2 +-
arch/arm/mach-ux500/Kconfig | 2 +-
arch/arm/mach-vexpress/Kconfig | 2 +-
arch/arm/mach-zynq/Kconfig | 2 +-
11 files changed, 56 insertions(+), 34 deletions(-)
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index d423d58..177cb39 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -636,7 +636,7 @@ config ARCH_SHMOBILE
select CLKDEV_LOOKUP
select GENERIC_CLOCKEVENTS
select HAVE_ARM_SCU if SMP
- select HAVE_ARM_TWD if LOCAL_TIMERS
+ select HAVE_ARM_TWD if SMP
select HAVE_CLK
select HAVE_MACH_CLKDEV
select HAVE_SMP
diff --git a/arch/arm/kernel/smp_twd.c b/arch/arm/kernel/smp_twd.c
index 90525d9..aac1495 100644
--- a/arch/arm/kernel/smp_twd.c
+++ b/arch/arm/kernel/smp_twd.c
@@ -11,6 +11,7 @@
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/clk.h>
+#include <linux/cpu.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/err.h>
@@ -24,7 +25,6 @@
#include <asm/smp_plat.h>
#include <asm/smp_twd.h>
-#include <asm/localtimer.h>
/* set up by the platform code */
static void __iomem *twd_base;
@@ -33,7 +33,7 @@ static struct clk *twd_clk;
static unsigned long twd_timer_rate;
static DEFINE_PER_CPU(bool, percpu_setup_called);
-static struct clock_event_device __percpu **twd_evt;
+static struct clock_event_device __percpu *twd_evt;
static int twd_ppi;
static void twd_set_mode(enum clock_event_mode mode,
@@ -90,8 +90,10 @@ static int twd_timer_ack(void)
return 0;
}
-static void twd_timer_stop(struct clock_event_device *clk)
+static void twd_timer_stop(void)
{
+ struct clock_event_device *clk = __this_cpu_ptr(twd_evt);
+
twd_set_mode(CLOCK_EVT_MODE_UNUSED, clk);
disable_percpu_irq(clk->irq);
}
@@ -106,7 +108,7 @@ static void twd_update_frequency(void *new_rate)
{
twd_timer_rate = *((unsigned long *) new_rate);
- clockevents_update_freq(*__this_cpu_ptr(twd_evt), twd_timer_rate);
+ clockevents_update_freq(__this_cpu_ptr(twd_evt), twd_timer_rate);
}
static int twd_rate_change(struct notifier_block *nb,
@@ -132,7 +134,7 @@ static struct notifier_block twd_clk_nb = {
static int twd_clk_init(void)
{
- if (twd_evt && *__this_cpu_ptr(twd_evt) && !IS_ERR(twd_clk))
+ if (twd_evt && __this_cpu_ptr(twd_evt) && !IS_ERR(twd_clk))
return clk_notifier_register(twd_clk, &twd_clk_nb);
return 0;
@@ -151,7 +153,7 @@ static void twd_update_frequency(void *data)
{
twd_timer_rate = clk_get_rate(twd_clk);
- clockevents_update_freq(*__this_cpu_ptr(twd_evt), twd_timer_rate);
+ clockevents_update_freq(__this_cpu_ptr(twd_evt), twd_timer_rate);
}
static int twd_cpufreq_transition(struct notifier_block *nb,
@@ -177,7 +179,7 @@ static struct notifier_block twd_cpufreq_nb = {
static int twd_cpufreq_init(void)
{
- if (twd_evt && *__this_cpu_ptr(twd_evt) && !IS_ERR(twd_clk))
+ if (twd_evt && __this_cpu_ptr(twd_evt) && !IS_ERR(twd_clk))
return cpufreq_register_notifier(&twd_cpufreq_nb,
CPUFREQ_TRANSITION_NOTIFIER);
@@ -228,7 +230,7 @@ static void __cpuinit twd_calibrate_rate(void)
static irqreturn_t twd_handler(int irq, void *dev_id)
{
- struct clock_event_device *evt = *(struct clock_event_device **)dev_id;
+ struct clock_event_device *evt = dev_id;
if (twd_timer_ack()) {
evt->event_handler(evt);
@@ -265,9 +267,9 @@ static void twd_get_clock(struct device_node *np)
/*
* Setup the local clock events for a CPU.
*/
-static int __cpuinit twd_timer_setup(struct clock_event_device *clk)
+static void __cpuinit twd_timer_setup(void)
{
- struct clock_event_device **this_cpu_clk;
+ struct clock_event_device *clk = __this_cpu_ptr(twd_evt);
int cpu = smp_processor_id();
/*
@@ -276,9 +278,9 @@ static int __cpuinit twd_timer_setup(struct clock_event_device *clk)
*/
if (per_cpu(percpu_setup_called, cpu)) {
__raw_writel(0, twd_base + TWD_TIMER_CONTROL);
- clockevents_register_device(*__this_cpu_ptr(twd_evt));
+ clockevents_register_device(clk);
enable_percpu_irq(clk->irq, 0);
- return 0;
+ return;
}
per_cpu(percpu_setup_called, cpu) = true;
@@ -297,27 +299,37 @@ static int __cpuinit twd_timer_setup(struct clock_event_device *clk)
clk->set_mode = twd_set_mode;
clk->set_next_event = twd_set_next_event;
clk->irq = twd_ppi;
-
- this_cpu_clk = __this_cpu_ptr(twd_evt);
- *this_cpu_clk = clk;
+ clk->cpumask = cpumask_of(cpu);
clockevents_config_and_register(clk, twd_timer_rate,
0xf, 0xffffffff);
enable_percpu_irq(clk->irq, 0);
+}
- return 0;
+static int __cpuinit twd_timer_cpu_notify(struct notifier_block *self,
+ unsigned long action, void *hcpu)
+{
+ switch (action & ~CPU_TASKS_FROZEN) {
+ case CPU_STARTING:
+ twd_timer_setup();
+ break;
+ case CPU_DYING:
+ twd_timer_stop();
+ break;
+ }
+
+ return NOTIFY_OK;
}
-static struct local_timer_ops twd_lt_ops __cpuinitdata = {
- .setup = twd_timer_setup,
- .stop = twd_timer_stop,
+static struct notifier_block twd_timer_cpu_nb __cpuinitdata = {
+ .notifier_call = twd_timer_cpu_notify,
};
static int __init twd_local_timer_common_register(struct device_node *np)
{
int err;
- twd_evt = alloc_percpu(struct clock_event_device *);
+ twd_evt = alloc_percpu(struct clock_event_device);
if (!twd_evt) {
err = -ENOMEM;
goto out_free;
@@ -329,12 +341,22 @@ static int __init twd_local_timer_common_register(struct device_node *np)
goto out_free;
}
- err = local_timer_register(&twd_lt_ops);
+ err = register_cpu_notifier(&twd_timer_cpu_nb);
if (err)
goto out_irq;
twd_get_clock(np);
+ /*
+ * Immediately configure the timer on the boot CPU, unless we need
+ * jiffies to be incrementing to calibrate the rate in which case
+ * setup the timer in late_time_init.
+ */
+ if (twd_timer_rate)
+ twd_timer_setup();
+ else
+ late_time_init = twd_timer_setup;
+
return 0;
out_irq:
diff --git a/arch/arm/mach-highbank/Kconfig b/arch/arm/mach-highbank/Kconfig
index cd9fcb1..6acbdab 100644
--- a/arch/arm/mach-highbank/Kconfig
+++ b/arch/arm/mach-highbank/Kconfig
@@ -12,7 +12,7 @@ config ARCH_HIGHBANK
select CPU_V7
select GENERIC_CLOCKEVENTS
select HAVE_ARM_SCU
- select HAVE_ARM_TWD if LOCAL_TIMERS
+ select HAVE_ARM_TWD if SMP
select HAVE_SMP
select MAILBOX
select PL320_MBOX
diff --git a/arch/arm/mach-imx/Kconfig b/arch/arm/mach-imx/Kconfig
index ba44328..c8adc79 100644
--- a/arch/arm/mach-imx/Kconfig
+++ b/arch/arm/mach-imx/Kconfig
@@ -798,7 +798,7 @@ config SOC_IMX6Q
select COMMON_CLK
select CPU_V7
select HAVE_ARM_SCU if SMP
- select HAVE_ARM_TWD if LOCAL_TIMERS
+ select HAVE_ARM_TWD if SMP
select HAVE_CAN_FLEXCAN if CAN
select HAVE_IMX_ANATOP
select HAVE_IMX_GPC
diff --git a/arch/arm/mach-omap2/Kconfig b/arch/arm/mach-omap2/Kconfig
index f49cd51..edb950a 100644
--- a/arch/arm/mach-omap2/Kconfig
+++ b/arch/arm/mach-omap2/Kconfig
@@ -90,7 +90,7 @@ config ARCH_OMAP4
select CACHE_L2X0
select CPU_V7
select HAVE_ARM_SCU if SMP
- select HAVE_ARM_TWD if LOCAL_TIMERS
+ select HAVE_ARM_TWD if SMP
select HAVE_SMP
select LOCAL_TIMERS if SMP
select OMAP_INTERCONNECT
diff --git a/arch/arm/mach-realview/Kconfig b/arch/arm/mach-realview/Kconfig
index d210c0f9..9db2029 100644
--- a/arch/arm/mach-realview/Kconfig
+++ b/arch/arm/mach-realview/Kconfig
@@ -13,7 +13,7 @@ config REALVIEW_EB_A9MP
depends on MACH_REALVIEW_EB
select CPU_V7
select HAVE_ARM_SCU if SMP
- select HAVE_ARM_TWD if LOCAL_TIMERS
+ select HAVE_ARM_TWD if SMP
select HAVE_SMP
select MIGHT_HAVE_CACHE_L2X0
help
@@ -26,7 +26,7 @@ config REALVIEW_EB_ARM11MP
select ARCH_HAS_BARRIERS if SMP
select CPU_V6K
select HAVE_ARM_SCU if SMP
- select HAVE_ARM_TWD if LOCAL_TIMERS
+ select HAVE_ARM_TWD if SMP
select HAVE_SMP
select MIGHT_HAVE_CACHE_L2X0
help
@@ -48,7 +48,7 @@ config MACH_REALVIEW_PB11MP
select ARM_GIC
select CPU_V6K
select HAVE_ARM_SCU if SMP
- select HAVE_ARM_TWD if LOCAL_TIMERS
+ select HAVE_ARM_TWD if SMP
select HAVE_PATA_PLATFORM
select HAVE_SMP
select MIGHT_HAVE_CACHE_L2X0
@@ -92,7 +92,7 @@ config MACH_REALVIEW_PBX
select ARCH_SPARSEMEM_ENABLE if CPU_V7 && !REALVIEW_HIGH_PHYS_OFFSET
select ARM_GIC
select HAVE_ARM_SCU if SMP
- select HAVE_ARM_TWD if LOCAL_TIMERS
+ select HAVE_ARM_TWD if SMP
select HAVE_PATA_PLATFORM
select HAVE_SMP
select MIGHT_HAVE_CACHE_L2X0
diff --git a/arch/arm/mach-spear/Kconfig b/arch/arm/mach-spear/Kconfig
index 442917e..df0d59a 100644
--- a/arch/arm/mach-spear/Kconfig
+++ b/arch/arm/mach-spear/Kconfig
@@ -23,7 +23,7 @@ config ARCH_SPEAR13XX
select CPU_V7
select GPIO_SPEAR_SPICS
select HAVE_ARM_SCU if SMP
- select HAVE_ARM_TWD if LOCAL_TIMERS
+ select HAVE_ARM_TWD if SMP
select HAVE_SMP
select MIGHT_HAVE_CACHE_L2X0
select PINCTRL
diff --git a/arch/arm/mach-tegra/Kconfig b/arch/arm/mach-tegra/Kconfig
index 84d72fc..1f3ea1f 100644
--- a/arch/arm/mach-tegra/Kconfig
+++ b/arch/arm/mach-tegra/Kconfig
@@ -8,7 +8,7 @@ config ARCH_TEGRA
select COMMON_CLK
select GENERIC_CLOCKEVENTS
select HAVE_ARM_SCU if SMP
- select HAVE_ARM_TWD if LOCAL_TIMERS
+ select HAVE_ARM_TWD if SMP
select HAVE_CLK
select HAVE_SMP
select MIGHT_HAVE_CACHE_L2X0
diff --git a/arch/arm/mach-ux500/Kconfig b/arch/arm/mach-ux500/Kconfig
index 6a4387e..0614ee2 100644
--- a/arch/arm/mach-ux500/Kconfig
+++ b/arch/arm/mach-ux500/Kconfig
@@ -8,7 +8,7 @@ config ARCH_U8500
select CPU_V7
select GENERIC_CLOCKEVENTS
select HAVE_ARM_SCU if SMP
- select HAVE_ARM_TWD if LOCAL_TIMERS
+ select HAVE_ARM_TWD if SMP
select HAVE_SMP
select MIGHT_HAVE_CACHE_L2X0
help
diff --git a/arch/arm/mach-vexpress/Kconfig b/arch/arm/mach-vexpress/Kconfig
index 5907e10..5bfdd73 100644
--- a/arch/arm/mach-vexpress/Kconfig
+++ b/arch/arm/mach-vexpress/Kconfig
@@ -10,7 +10,7 @@ config ARCH_VEXPRESS
select CPU_V7
select GENERIC_CLOCKEVENTS
select HAVE_ARM_SCU if SMP
- select HAVE_ARM_TWD if LOCAL_TIMERS
+ select HAVE_ARM_TWD if SMP
select HAVE_CLK
select HAVE_PATA_PLATFORM
select HAVE_SMP
diff --git a/arch/arm/mach-zynq/Kconfig b/arch/arm/mach-zynq/Kconfig
index c1d61f2..04f8a4a 100644
--- a/arch/arm/mach-zynq/Kconfig
+++ b/arch/arm/mach-zynq/Kconfig
@@ -6,7 +6,7 @@ config ARCH_ZYNQ
select CPU_V7
select GENERIC_CLOCKEVENTS
select HAVE_ARM_SCU if SMP
- select HAVE_ARM_TWD if LOCAL_TIMERS
+ select HAVE_ARM_TWD if SMP
select ICST
select MIGHT_HAVE_CACHE_L2X0
select USE_OF
--
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