[RFC PATCH 3/3] ARM: gic, local timers: use the request_percpu_irq() interface
Marc Zyngier
marc.zyngier at arm.com
Thu Sep 15 12:52:31 EDT 2011
This patch remove the hardcoded link between local timers and PPIs,
and convert the PPI users (TWD and MSM timers) to the new *_percpu_irq
interface.
PPIs are now useable for more than just the local timers.
Cc: David Brown <davidb at codeaurora.org>
Signed-off-by: Marc Zyngier <marc.zyngier at arm.com>
---
arch/arm/common/gic.c | 52 --------------------------
arch/arm/include/asm/hardware/gic.h | 1 -
arch/arm/include/asm/localtimer.h | 17 ++++-----
arch/arm/include/asm/smp_twd.h | 2 +-
arch/arm/kernel/smp.c | 16 +--------
arch/arm/kernel/smp_twd.c | 47 +++++++++++++++++++++++-
arch/arm/mach-exynos4/mct.c | 5 ---
arch/arm/mach-msm/timer.c | 69 ++++++++++++++++++++---------------
8 files changed, 94 insertions(+), 115 deletions(-)
diff --git a/arch/arm/common/gic.c b/arch/arm/common/gic.c
index 4bbcce8..8e2f0c3 100644
--- a/arch/arm/common/gic.c
+++ b/arch/arm/common/gic.c
@@ -35,7 +35,6 @@
#include <asm/irq.h>
#include <asm/mach/irq.h>
#include <asm/hardware/gic.h>
-#include <asm/localtimer.h>
static DEFINE_SPINLOCK(irq_controller_lock);
@@ -259,32 +258,6 @@ void __init gic_cascade_irq(unsigned int gic_nr, unsigned int irq)
irq_set_chained_handler(irq, gic_handle_cascade_irq);
}
-#ifdef CONFIG_LOCAL_TIMERS
-#define gic_ppi_handler percpu_timer_handler
-#else
-static irqreturn_t gic_ppi_handler(int irq, void *dev_id)
-{
- return IRQ_NONE;
-}
-#endif
-
-#define PPI_IRQACT(nr) \
- { \
- .handler = gic_ppi_handler, \
- .flags = IRQF_PERCPU | IRQF_TIMER, \
- .irq = nr, \
- .name = "PPI-" # nr, \
- }
-
-static struct irqaction ppi_irqaction_template[16] __initdata = {
- PPI_IRQACT(0), PPI_IRQACT(1), PPI_IRQACT(2), PPI_IRQACT(3),
- PPI_IRQACT(4), PPI_IRQACT(5), PPI_IRQACT(6), PPI_IRQACT(7),
- PPI_IRQACT(8), PPI_IRQACT(9), PPI_IRQACT(10), PPI_IRQACT(11),
- PPI_IRQACT(12), PPI_IRQACT(13), PPI_IRQACT(14), PPI_IRQACT(15),
-};
-
-static struct irqaction *ppi_irqaction;
-
static void __init gic_dist_init(struct gic_chip_data *gic,
unsigned int irq_start)
{
@@ -320,16 +293,6 @@ static void __init gic_dist_init(struct gic_chip_data *gic,
if (gic == &gic_data[0]) {
nrppis = 16 - (irq_start & 15);
ppi_base = gic->irq_offset + 32 - nrppis;
-
- ppi_irqaction = kmemdup(&ppi_irqaction_template[16 - nrppis],
- sizeof(*ppi_irqaction) * nrppis,
- GFP_KERNEL);
-
- if (nrppis && !ppi_irqaction) {
- pr_err("GIC: Can't allocate PPI memory");
- nrppis = 0;
- ppi_base = 0;
- }
}
pr_info("Configuring GIC with %d sources (%d PPIs)\n",
@@ -372,17 +335,12 @@ static void __init gic_dist_init(struct gic_chip_data *gic,
*/
for (i = 0; i < nrppis; i++) {
int ppi = i + ppi_base;
- int err;
irq_set_percpu_devid(ppi);
irq_set_chip_and_handler(ppi, &gic_chip,
handle_percpu_devid_irq);
irq_set_chip_data(ppi, gic);
set_irq_flags(ppi, IRQF_VALID | IRQF_NOAUTOEN);
-
- err = setup_percpu_irq(ppi, &ppi_irqaction[i]);
- if (err)
- pr_err("GIC: can't setup PPI%d (%d)\n", ppi, err);
}
for (i = irq_start + nrppis; i < irq_limit; i++) {
@@ -443,16 +401,6 @@ void __cpuinit gic_secondary_init(unsigned int gic_nr)
gic_cpu_init(&gic_data[gic_nr]);
}
-void __cpuinit gic_enable_ppi(unsigned int irq)
-{
- unsigned long flags;
-
- local_irq_save(flags);
- irq_set_status_flags(irq, IRQ_NOPROBE);
- gic_unmask_irq(irq_get_irq_data(irq));
- local_irq_restore(flags);
-}
-
#ifdef CONFIG_SMP
void gic_raise_softirq(const struct cpumask *mask, unsigned int irq)
{
diff --git a/arch/arm/include/asm/hardware/gic.h b/arch/arm/include/asm/hardware/gic.h
index 435d3f8..2dadd50 100644
--- a/arch/arm/include/asm/hardware/gic.h
+++ b/arch/arm/include/asm/hardware/gic.h
@@ -40,7 +40,6 @@ void gic_init(unsigned int, unsigned int, void __iomem *, void __iomem *);
void gic_secondary_init(unsigned int);
void gic_cascade_irq(unsigned int gic_nr, unsigned int irq);
void gic_raise_softirq(const struct cpumask *mask, unsigned int irq);
-void gic_enable_ppi(unsigned int);
struct gic_chip_data {
unsigned int irq_offset;
diff --git a/arch/arm/include/asm/localtimer.h b/arch/arm/include/asm/localtimer.h
index e3663f7..f5e1cec 100644
--- a/arch/arm/include/asm/localtimer.h
+++ b/arch/arm/include/asm/localtimer.h
@@ -19,27 +19,20 @@ struct clock_event_device;
*/
void percpu_timer_setup(void);
-/*
- * Per-cpu timer IRQ handler
- */
-irqreturn_t percpu_timer_handler(int irq, void *dev_id);
-
-
#ifdef CONFIG_LOCAL_TIMERS
#ifdef CONFIG_HAVE_ARM_TWD
#include "smp_twd.h"
-#define local_timer_ack() twd_timer_ack()
+#define local_timer_stop(c) twd_timer_stop((c))
#else
/*
- * Platform provides this to acknowledge a local timer IRQ.
- * Returns true if the local timer IRQ is to be processed.
+ * Stop the local timer
*/
-int local_timer_ack(void);
+void local_timer_stop(struct clock_event_device *);
#endif
@@ -54,6 +47,10 @@ static inline int local_timer_setup(struct clock_event_device *evt)
{
return -ENXIO;
}
+
+static inline void local_timer_stop(struct clock_event_device *evt)
+{
+}
#endif
#endif
diff --git a/arch/arm/include/asm/smp_twd.h b/arch/arm/include/asm/smp_twd.h
index fed9981..ef9ffba 100644
--- a/arch/arm/include/asm/smp_twd.h
+++ b/arch/arm/include/asm/smp_twd.h
@@ -22,7 +22,7 @@ struct clock_event_device;
extern void __iomem *twd_base;
-int twd_timer_ack(void);
void twd_timer_setup(struct clock_event_device *);
+void twd_timer_stop(struct clock_event_device *);
#endif
diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c
index e3dbd99..c206aed 100644
--- a/arch/arm/kernel/smp.c
+++ b/arch/arm/kernel/smp.c
@@ -520,20 +520,6 @@ static void ipi_timer(void)
irq_exit();
}
-#ifdef CONFIG_LOCAL_TIMERS
-irqreturn_t percpu_timer_handler(int irq, void *dev_id)
-{
- struct clock_event_device *evt = &__get_cpu_var(percpu_clockevent);
-
- if (local_timer_ack()) {
- evt->event_handler(evt);
- return IRQ_HANDLED;
- }
-
- return IRQ_NONE;
-}
-#endif
-
#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
static void smp_timer_broadcast(const struct cpumask *mask)
{
@@ -584,7 +570,7 @@ static void percpu_timer_stop(void)
unsigned int cpu = smp_processor_id();
struct clock_event_device *evt = &per_cpu(percpu_clockevent, cpu);
- evt->set_mode(CLOCK_EVT_MODE_UNUSED, evt);
+ local_timer_stop(evt);
}
#endif
diff --git a/arch/arm/kernel/smp_twd.c b/arch/arm/kernel/smp_twd.c
index 01c1862..566c0fe 100644
--- a/arch/arm/kernel/smp_twd.c
+++ b/arch/arm/kernel/smp_twd.c
@@ -19,6 +19,7 @@
#include <linux/io.h>
#include <asm/smp_twd.h>
+#include <asm/localtimer.h>
#include <asm/hardware/gic.h>
/* set up by the platform code */
@@ -26,6 +27,8 @@ void __iomem *twd_base;
static unsigned long twd_timer_rate;
+static struct clock_event_device __percpu **twd_evt;
+
static void twd_set_mode(enum clock_event_mode mode,
struct clock_event_device *clk)
{
@@ -80,6 +83,12 @@ int twd_timer_ack(void)
return 0;
}
+void twd_timer_stop(struct clock_event_device *clk)
+{
+ twd_set_mode(CLOCK_EVT_MODE_UNUSED, clk);
+ disable_percpu_irq(clk->irq);
+}
+
static void __cpuinit twd_calibrate_rate(void)
{
unsigned long count;
@@ -119,11 +128,43 @@ 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;
+
+ if (twd_timer_ack()) {
+ evt->event_handler(evt);
+ return IRQ_HANDLED;
+ }
+
+ return IRQ_NONE;
+}
+
/*
* Setup the local clock events for a CPU.
*/
void __cpuinit twd_timer_setup(struct clock_event_device *clk)
{
+ struct clock_event_device **this_cpu_clk;
+
+ if (!twd_evt) {
+ int err;
+
+ twd_evt = alloc_percpu(struct clock_event_device *);
+ if (!twd_evt) {
+ pr_err("twd: can't allocate memory\n");
+ return;
+ }
+
+ err = request_percpu_irq(clk->irq, twd_handler,
+ "twd", twd_evt);
+ if (err) {
+ pr_err("twd: can't register interrupt %d (%d)\n",
+ clk->irq, err);
+ return;
+ }
+ }
+
twd_calibrate_rate();
clk->name = "local_timer";
@@ -137,8 +178,10 @@ void __cpuinit twd_timer_setup(struct clock_event_device *clk)
clk->max_delta_ns = clockevent_delta2ns(0xffffffff, clk);
clk->min_delta_ns = clockevent_delta2ns(0xf, clk);
+ this_cpu_clk = __this_cpu_ptr(twd_evt);
+ *this_cpu_clk = clk;
+
clockevents_register_device(clk);
- /* Make sure our local interrupt controller has this enabled */
- gic_enable_ppi(clk->irq);
+ enable_percpu_irq(clk->irq);
}
diff --git a/arch/arm/mach-exynos4/mct.c b/arch/arm/mach-exynos4/mct.c
index f3638fa..3a1e4f3 100644
--- a/arch/arm/mach-exynos4/mct.c
+++ b/arch/arm/mach-exynos4/mct.c
@@ -396,11 +396,6 @@ int __cpuinit local_timer_setup(struct clock_event_device *evt)
return 0;
}
-int local_timer_ack(void)
-{
- return 0;
-}
-
#endif /* CONFIG_LOCAL_TIMERS */
static void __init exynos4_timer_resources(void)
diff --git a/arch/arm/mach-msm/timer.c b/arch/arm/mach-msm/timer.c
index 63621f1..701d5e6 100644
--- a/arch/arm/mach-msm/timer.c
+++ b/arch/arm/mach-msm/timer.c
@@ -71,12 +71,16 @@ enum timer_location {
struct msm_clock {
struct clock_event_device clockevent;
struct clocksource clocksource;
- struct irqaction irq;
+ unsigned int irq;
void __iomem *regbase;
uint32_t freq;
uint32_t shift;
void __iomem *global_counter;
void __iomem *local_counter;
+ union {
+ struct clock_event_device *evt;
+ struct clock_event_device __percpu **percpu_evt;
+ };
};
enum {
@@ -87,13 +91,10 @@ enum {
static struct msm_clock msm_clocks[];
-static struct clock_event_device *local_clock_event;
static irqreturn_t msm_timer_interrupt(int irq, void *dev_id)
{
- struct clock_event_device *evt = dev_id;
- if (smp_processor_id() != 0)
- evt = local_clock_event;
+ struct clock_event_device *evt = *(struct clock_event_device **)dev_id;
if (evt->event_handler == NULL)
return IRQ_HANDLED;
evt->event_handler(evt);
@@ -171,13 +172,7 @@ static struct msm_clock msm_clocks[] = {
.mask = CLOCKSOURCE_MASK(32),
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
},
- .irq = {
- .name = "gp_timer",
- .flags = IRQF_DISABLED | IRQF_TIMER | IRQF_TRIGGER_RISING,
- .handler = msm_timer_interrupt,
- .dev_id = &msm_clocks[0].clockevent,
- .irq = INT_GP_TIMER_EXP
- },
+ .irq = INT_GP_TIMER_EXP,
.freq = GPT_HZ,
},
[MSM_CLOCK_DGT] = {
@@ -196,13 +191,7 @@ static struct msm_clock msm_clocks[] = {
.mask = CLOCKSOURCE_MASK((32 - MSM_DGT_SHIFT)),
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
},
- .irq = {
- .name = "dg_timer",
- .flags = IRQF_DISABLED | IRQF_TIMER | IRQF_TRIGGER_RISING,
- .handler = msm_timer_interrupt,
- .dev_id = &msm_clocks[1].clockevent,
- .irq = INT_DEBUG_TIMER_EXP
- },
+ .irq = INT_DEBUG_TIMER_EXP,
.freq = DGT_HZ >> MSM_DGT_SHIFT,
.shift = MSM_DGT_SHIFT,
}
@@ -261,10 +250,30 @@ static void __init msm_timer_init(void)
printk(KERN_ERR "msm_timer_init: clocksource_register "
"failed for %s\n", cs->name);
- res = setup_irq(clock->irq.irq, &clock->irq);
+ ce->irq = clock->irq;
+ if (cpu_is_msm8x60() || cpu_is_msm8960()) {
+ clock->percpu_evt = alloc_percpu(struct clock_event_device *);
+ if (!clock->percpu_evt) {
+ pr_err("msm_timer_init: memory allocation "
+ "failed for %s\n", ce->name);
+ continue;
+ }
+
+ *__this_cpu_ptr(clock->percpu_evt) = ce;
+ res = request_percpu_irq(ce->irq, msm_timer_interrupt,
+ ce->name, clock->percpu_evt);
+ if (!res)
+ enable_percpu_irq(ce->irq);
+ } else {
+ clock->evt = ce;
+ res = request_irq(ce->irq, msm_timer_interrupt,
+ IRQF_TIMER | IRQF_NOBALANCING | IRQF_TRIGGER_RISING,
+ ce->name, &clock->evt);
+ }
+
if (res)
- printk(KERN_ERR "msm_timer_init: setup_irq "
- "failed for %s\n", cs->name);
+ pr_err("msm_timer_init: request_irq failed for %s\n",
+ ce->name);
clockevents_register_device(ce);
}
@@ -273,6 +282,7 @@ static void __init msm_timer_init(void)
#ifdef CONFIG_SMP
int __cpuinit local_timer_setup(struct clock_event_device *evt)
{
+ static bool local_timer_inited;
struct msm_clock *clock = &msm_clocks[MSM_GLOBAL_TIMER];
/* Use existing clock_event for cpu 0 */
@@ -281,12 +291,13 @@ int __cpuinit local_timer_setup(struct clock_event_device *evt)
writel(DGT_CLK_CTL_DIV_4, MSM_TMR_BASE + DGT_CLK_CTL);
- if (!local_clock_event) {
+ if (!local_timer_inited) {
writel(0, clock->regbase + TIMER_ENABLE);
writel(0, clock->regbase + TIMER_CLEAR);
writel(~0, clock->regbase + TIMER_MATCH_VAL);
+ local_timer_inited = true;
}
- evt->irq = clock->irq.irq;
+ evt->irq = clock->irq;
evt->name = "local_timer";
evt->features = CLOCK_EVT_FEAT_ONESHOT;
evt->rating = clock->clockevent.rating;
@@ -298,17 +309,17 @@ int __cpuinit local_timer_setup(struct clock_event_device *evt)
clockevent_delta2ns(0xf0000000 >> clock->shift, evt);
evt->min_delta_ns = clockevent_delta2ns(4, evt);
- local_clock_event = evt;
-
- gic_enable_ppi(clock->irq.irq);
+ *__this_cpu_ptr(clock->percpu_evt) = evt;
+ enable_percpu_irq(evt->irq);
clockevents_register_device(evt);
return 0;
}
-inline int local_timer_ack(void)
+void local_timer_stop(struct clock_event_device *evt)
{
- return 1;
+ evt->set_mode(CLOCK_EVT_MODE_UNUSED, evt);
+ disable_percpu_irq(evt->irq);
}
#endif
--
1.7.0.4
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