help
This option enables support for the ARM system coherency unit
-config ARM_ARCH_TIMER
+config HAVE_ARM_ARCH_TIMER
bool "Architected timer support"
depends on CPU_V7
+ select ARM_ARCH_TIMER
help
This option enables support for the ARM architected timer
#include <asm/barrier.h>
#include <asm/errno.h>
#include <linux/clocksource.h>
+#include <linux/init.h>
#include <linux/types.h>
+#include <clocksource/arm_arch_timer.h>
+
#ifdef CONFIG_ARM_ARCH_TIMER
int arch_timer_of_register(void);
int arch_timer_sched_clock_init(void);
-struct timecounter *arch_timer_get_timecounter(void);
-
-#define ARCH_TIMER_CTRL_ENABLE (1 << 0)
-#define ARCH_TIMER_CTRL_IT_MASK (1 << 1)
-#define ARCH_TIMER_CTRL_IT_STAT (1 << 2)
-
-#define ARCH_TIMER_REG_CTRL 0
-#define ARCH_TIMER_REG_TVAL 1
-
-#define ARCH_TIMER_PHYS_ACCESS 0
-#define ARCH_TIMER_VIRT_ACCESS 1
/*
* These register accessors are marked inline so the compiler can
{
return -ENXIO;
}
-
-static inline struct timecounter *arch_timer_get_timecounter(void)
-{
- return NULL;
-}
#endif
#endif
* published by the Free Software Foundation.
*/
#include <linux/init.h>
-#include <linux/kernel.h>
-#include <linux/delay.h>
-#include <linux/device.h>
-#include <linux/smp.h>
-#include <linux/cpu.h>
-#include <linux/jiffies.h>
-#include <linux/clockchips.h>
-#include <linux/interrupt.h>
-#include <linux/of_irq.h>
-#include <linux/io.h>
+#include <linux/types.h>
#include <asm/delay.h>
-#include <asm/arch_timer.h>
#include <asm/sched_clock.h>
-static u32 arch_timer_rate;
+#include <clocksource/arm_arch_timer.h>
-enum ppi_nr {
- PHYS_SECURE_PPI,
- PHYS_NONSECURE_PPI,
- VIRT_PPI,
- HYP_PPI,
- MAX_TIMER_PPI
-};
-
-static int arch_timer_ppi[MAX_TIMER_PPI];
-
-static struct clock_event_device __percpu *arch_timer_evt;
-static struct delay_timer arch_delay_timer;
-
-static bool arch_timer_use_virtual = true;
-
-/*
- * Architected system timer support.
- */
-
-static irqreturn_t inline timer_handler(const int access,
- struct clock_event_device *evt)
-{
- unsigned long ctrl;
- ctrl = arch_timer_reg_read(access, ARCH_TIMER_REG_CTRL);
- if (ctrl & ARCH_TIMER_CTRL_IT_STAT) {
- ctrl |= ARCH_TIMER_CTRL_IT_MASK;
- arch_timer_reg_write(access, ARCH_TIMER_REG_CTRL, ctrl);
- evt->event_handler(evt);
- return IRQ_HANDLED;
- }
-
- return IRQ_NONE;
-}
-
-static irqreturn_t arch_timer_handler_virt(int irq, void *dev_id)
-{
- struct clock_event_device *evt = dev_id;
-
- return timer_handler(ARCH_TIMER_VIRT_ACCESS, evt);
-}
-
-static irqreturn_t arch_timer_handler_phys(int irq, void *dev_id)
-{
- struct clock_event_device *evt = dev_id;
-
- return timer_handler(ARCH_TIMER_PHYS_ACCESS, evt);
-}
-
-static inline void timer_set_mode(const int access, int mode)
-{
- unsigned long ctrl;
- switch (mode) {
- case CLOCK_EVT_MODE_UNUSED:
- case CLOCK_EVT_MODE_SHUTDOWN:
- ctrl = arch_timer_reg_read(access, ARCH_TIMER_REG_CTRL);
- ctrl &= ~ARCH_TIMER_CTRL_ENABLE;
- arch_timer_reg_write(access, ARCH_TIMER_REG_CTRL, ctrl);
- break;
- default:
- break;
- }
-}
-
-static void arch_timer_set_mode_virt(enum clock_event_mode mode,
- struct clock_event_device *clk)
-{
- timer_set_mode(ARCH_TIMER_VIRT_ACCESS, mode);
-}
-
-static void arch_timer_set_mode_phys(enum clock_event_mode mode,
- struct clock_event_device *clk)
-{
- timer_set_mode(ARCH_TIMER_PHYS_ACCESS, mode);
-}
-
-static inline void set_next_event(const int access, unsigned long evt)
-{
- unsigned long ctrl;
- ctrl = arch_timer_reg_read(access, ARCH_TIMER_REG_CTRL);
- ctrl |= ARCH_TIMER_CTRL_ENABLE;
- ctrl &= ~ARCH_TIMER_CTRL_IT_MASK;
- arch_timer_reg_write(access, ARCH_TIMER_REG_TVAL, evt);
- arch_timer_reg_write(access, ARCH_TIMER_REG_CTRL, ctrl);
-}
-
-static int arch_timer_set_next_event_virt(unsigned long evt,
- struct clock_event_device *unused)
-{
- set_next_event(ARCH_TIMER_VIRT_ACCESS, evt);
- return 0;
-}
-
-static int arch_timer_set_next_event_phys(unsigned long evt,
- struct clock_event_device *unused)
-{
- set_next_event(ARCH_TIMER_PHYS_ACCESS, evt);
- return 0;
-}
-
-static int __cpuinit arch_timer_setup(struct clock_event_device *clk)
-{
- clk->features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_C3STOP;
- clk->name = "arch_sys_timer";
- clk->rating = 450;
- if (arch_timer_use_virtual) {
- clk->irq = arch_timer_ppi[VIRT_PPI];
- clk->set_mode = arch_timer_set_mode_virt;
- clk->set_next_event = arch_timer_set_next_event_virt;
- } else {
- clk->irq = arch_timer_ppi[PHYS_SECURE_PPI];
- clk->set_mode = arch_timer_set_mode_phys;
- clk->set_next_event = arch_timer_set_next_event_phys;
- }
-
- clk->cpumask = cpumask_of(smp_processor_id());
-
- clk->set_mode(CLOCK_EVT_MODE_SHUTDOWN, NULL);
-
- clockevents_config_and_register(clk, arch_timer_rate,
- 0xf, 0x7fffffff);
-
- if (arch_timer_use_virtual)
- enable_percpu_irq(arch_timer_ppi[VIRT_PPI], 0);
- else {
- enable_percpu_irq(arch_timer_ppi[PHYS_SECURE_PPI], 0);
- if (arch_timer_ppi[PHYS_NONSECURE_PPI])
- enable_percpu_irq(arch_timer_ppi[PHYS_NONSECURE_PPI], 0);
- }
-
- arch_counter_set_user_access();
-
- return 0;
-}
-
-static int arch_timer_available(void)
-{
- u32 freq;
-
- if (arch_timer_rate == 0) {
- freq = arch_timer_get_cntfrq();
-
- /* Check the timer frequency. */
- if (freq == 0) {
- pr_warn("Architected timer frequency not available\n");
- return -EINVAL;
- }
-
- arch_timer_rate = freq;
- }
-
- pr_info_once("Architected local timer running at %lu.%02luMHz (%s).\n",
- (unsigned long)arch_timer_rate / 1000000,
- (unsigned long)(arch_timer_rate / 10000) % 100,
- arch_timer_use_virtual ? "virt" : "phys");
- return 0;
-}
-
-/*
- * Some external users of arch_timer_read_counter (e.g. sched_clock) may try to
- * call it before it has been initialised. Rather than incur a performance
- * penalty checking for initialisation, provide a default implementation that
- * won't lead to time appearing to jump backwards.
- */
-static u64 arch_timer_read_zero(void)
-{
- return 0;
-}
-
-u64 (*arch_timer_read_counter)(void) = arch_timer_read_zero;
-
-static u32 arch_timer_read_counter32(void)
-{
- return arch_timer_read_counter();
-}
-
-static cycle_t arch_counter_read(struct clocksource *cs)
+static unsigned long arch_timer_read_counter_long(void)
{
return arch_timer_read_counter();
}
-static unsigned long arch_timer_read_current_timer(void)
+static u32 arch_timer_read_counter_u32(void)
{
return arch_timer_read_counter();
}
-static cycle_t arch_counter_read_cc(const struct cyclecounter *cc)
-{
- return arch_timer_read_counter();
-}
-
-static struct clocksource clocksource_counter = {
- .name = "arch_sys_counter",
- .rating = 400,
- .read = arch_counter_read,
- .mask = CLOCKSOURCE_MASK(56),
- .flags = CLOCK_SOURCE_IS_CONTINUOUS,
-};
-
-static struct cyclecounter cyclecounter = {
- .read = arch_counter_read_cc,
- .mask = CLOCKSOURCE_MASK(56),
-};
-
-static struct timecounter timecounter;
-
-struct timecounter *arch_timer_get_timecounter(void)
-{
- return &timecounter;
-}
-
-static void __cpuinit arch_timer_stop(struct clock_event_device *clk)
-{
- pr_debug("arch_timer_teardown disable IRQ%d cpu #%d\n",
- clk->irq, smp_processor_id());
-
- if (arch_timer_use_virtual)
- disable_percpu_irq(arch_timer_ppi[VIRT_PPI]);
- else {
- disable_percpu_irq(arch_timer_ppi[PHYS_SECURE_PPI]);
- if (arch_timer_ppi[PHYS_NONSECURE_PPI])
- disable_percpu_irq(arch_timer_ppi[PHYS_NONSECURE_PPI]);
- }
-
- clk->set_mode(CLOCK_EVT_MODE_UNUSED, clk);
-}
-
-static int __cpuinit arch_timer_cpu_notify(struct notifier_block *self,
- unsigned long action, void *hcpu)
-{
- struct clock_event_device *evt = this_cpu_ptr(arch_timer_evt);
-
- switch (action & ~CPU_TASKS_FROZEN) {
- case CPU_STARTING:
- arch_timer_setup(evt);
- break;
- case CPU_DYING:
- arch_timer_stop(evt);
- break;
- }
-
- return NOTIFY_OK;
-}
-
-static struct notifier_block arch_timer_cpu_nb __cpuinitdata = {
- .notifier_call = arch_timer_cpu_notify,
-};
+static struct delay_timer arch_delay_timer;
-static int __init arch_timer_register(void)
+static void __init arch_timer_delay_timer_register(void)
{
- int err;
- int ppi;
-
- err = arch_timer_available();
- if (err)
- goto out;
-
- arch_timer_evt = alloc_percpu(struct clock_event_device);
- if (!arch_timer_evt) {
- err = -ENOMEM;
- goto out;
- }
-
- clocksource_register_hz(&clocksource_counter, arch_timer_rate);
- cyclecounter.mult = clocksource_counter.mult;
- cyclecounter.shift = clocksource_counter.shift;
- timecounter_init(&timecounter, &cyclecounter,
- arch_counter_get_cntpct());
-
- if (arch_timer_use_virtual) {
- ppi = arch_timer_ppi[VIRT_PPI];
- err = request_percpu_irq(ppi, arch_timer_handler_virt,
- "arch_timer", arch_timer_evt);
- } else {
- ppi = arch_timer_ppi[PHYS_SECURE_PPI];
- err = request_percpu_irq(ppi, arch_timer_handler_phys,
- "arch_timer", arch_timer_evt);
- if (!err && arch_timer_ppi[PHYS_NONSECURE_PPI]) {
- ppi = arch_timer_ppi[PHYS_NONSECURE_PPI];
- err = request_percpu_irq(ppi, arch_timer_handler_phys,
- "arch_timer", arch_timer_evt);
- if (err)
- free_percpu_irq(arch_timer_ppi[PHYS_SECURE_PPI],
- arch_timer_evt);
- }
- }
-
- if (err) {
- pr_err("arch_timer: can't register interrupt %d (%d)\n",
- ppi, err);
- goto out_free;
- }
-
- err = register_cpu_notifier(&arch_timer_cpu_nb);
- if (err)
- goto out_free_irq;
-
- /* Immediately configure the timer on the boot CPU */
- arch_timer_setup(this_cpu_ptr(arch_timer_evt));
-
/* Use the architected timer for the delay loop. */
- arch_delay_timer.read_current_timer = &arch_timer_read_current_timer;
- arch_delay_timer.freq = arch_timer_rate;
+ arch_delay_timer.read_current_timer = arch_timer_read_counter_long;
+ arch_delay_timer.freq = arch_timer_get_rate();
register_current_timer_delay(&arch_delay_timer);
- return 0;
-
-out_free_irq:
- if (arch_timer_use_virtual)
- free_percpu_irq(arch_timer_ppi[VIRT_PPI], arch_timer_evt);
- else {
- free_percpu_irq(arch_timer_ppi[PHYS_SECURE_PPI],
- arch_timer_evt);
- if (arch_timer_ppi[PHYS_NONSECURE_PPI])
- free_percpu_irq(arch_timer_ppi[PHYS_NONSECURE_PPI],
- arch_timer_evt);
- }
-
-out_free:
- free_percpu(arch_timer_evt);
-out:
- return err;
}
-static const struct of_device_id arch_timer_of_match[] __initconst = {
- { .compatible = "arm,armv7-timer", },
- {},
-};
-
int __init arch_timer_of_register(void)
{
- struct device_node *np;
- u32 freq;
- int i;
-
- np = of_find_matching_node(NULL, arch_timer_of_match);
- if (!np) {
- pr_err("arch_timer: can't find DT node\n");
- return -ENODEV;
- }
+ int ret;
- /* Try to determine the frequency from the device tree or CNTFRQ */
- if (!of_property_read_u32(np, "clock-frequency", &freq))
- arch_timer_rate = freq;
+ ret = arch_timer_init();
+ if (ret)
+ return ret;
- for (i = PHYS_SECURE_PPI; i < MAX_TIMER_PPI; i++)
- arch_timer_ppi[i] = irq_of_parse_and_map(np, i);
+ arch_timer_delay_timer_register();
- of_node_put(np);
-
- /*
- * If no interrupt provided for virtual timer, we'll have to
- * stick to the physical timer. It'd better be accessible...
- */
- if (!arch_timer_ppi[VIRT_PPI]) {
- arch_timer_use_virtual = false;
-
- if (!arch_timer_ppi[PHYS_SECURE_PPI] ||
- !arch_timer_ppi[PHYS_NONSECURE_PPI]) {
- pr_warn("arch_timer: No interrupt available, giving up\n");
- return -EINVAL;
- }
- }
-
- if (arch_timer_use_virtual)
- arch_timer_read_counter = arch_counter_get_cntvct;
- else
- arch_timer_read_counter = arch_counter_get_cntpct;
-
- return arch_timer_register();
+ return 0;
}
int __init arch_timer_sched_clock_init(void)
{
- int err;
-
- err = arch_timer_available();
- if (err)
- return err;
+ if (arch_timer_get_rate() == 0)
+ return -ENXIO;
- setup_sched_clock(arch_timer_read_counter32,
- 32, arch_timer_rate);
+ setup_sched_clock(arch_timer_read_counter_u32,
+ 32, arch_timer_get_rate());
return 0;
}
config SOC_OMAP5
bool "TI OMAP5"
- select ARM_ARCH_TIMER
select ARM_CPU_SUSPEND if PM
select ARM_GIC
select CPU_V7
select HAVE_SMP
select COMMON_CLK
+ select HAVE_ARM_ARCH_TIMER
comment "OMAP Core Type"
depends on ARCH_OMAP2
def_bool y if ARM64
help
This option enables support for the ARM generic timer.
+
+config ARM_ARCH_TIMER
+ bool
obj-$(CONFIG_SUNXI_TIMER) += sunxi_timer.o
obj-$(CONFIG_CLKSRC_ARM_GENERIC) += arm_generic.o
+obj-$(CONFIG_ARM_ARCH_TIMER) += arm_arch_timer.o
--- /dev/null
+/*
+ * linux/drivers/clocksource/arm_arch_timer.c
+ *
+ * Copyright (C) 2011 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/init.h>
+#include <linux/kernel.h>
+#include <linux/device.h>
+#include <linux/smp.h>
+#include <linux/cpu.h>
+#include <linux/clockchips.h>
+#include <linux/interrupt.h>
+#include <linux/of_irq.h>
+#include <linux/io.h>
+
+#include <asm/arch_timer.h>
+
+#include <clocksource/arm_arch_timer.h>
+
+static u32 arch_timer_rate;
+
+enum ppi_nr {
+ PHYS_SECURE_PPI,
+ PHYS_NONSECURE_PPI,
+ VIRT_PPI,
+ HYP_PPI,
+ MAX_TIMER_PPI
+};
+
+static int arch_timer_ppi[MAX_TIMER_PPI];
+
+static struct clock_event_device __percpu *arch_timer_evt;
+
+static bool arch_timer_use_virtual = true;
+
+/*
+ * Architected system timer support.
+ */
+
+static inline irqreturn_t timer_handler(const int access,
+ struct clock_event_device *evt)
+{
+ unsigned long ctrl;
+ ctrl = arch_timer_reg_read(access, ARCH_TIMER_REG_CTRL);
+ if (ctrl & ARCH_TIMER_CTRL_IT_STAT) {
+ ctrl |= ARCH_TIMER_CTRL_IT_MASK;
+ arch_timer_reg_write(access, ARCH_TIMER_REG_CTRL, ctrl);
+ evt->event_handler(evt);
+ return IRQ_HANDLED;
+ }
+
+ return IRQ_NONE;
+}
+
+static irqreturn_t arch_timer_handler_virt(int irq, void *dev_id)
+{
+ struct clock_event_device *evt = dev_id;
+
+ return timer_handler(ARCH_TIMER_VIRT_ACCESS, evt);
+}
+
+static irqreturn_t arch_timer_handler_phys(int irq, void *dev_id)
+{
+ struct clock_event_device *evt = dev_id;
+
+ return timer_handler(ARCH_TIMER_PHYS_ACCESS, evt);
+}
+
+static inline void timer_set_mode(const int access, int mode)
+{
+ unsigned long ctrl;
+ switch (mode) {
+ case CLOCK_EVT_MODE_UNUSED:
+ case CLOCK_EVT_MODE_SHUTDOWN:
+ ctrl = arch_timer_reg_read(access, ARCH_TIMER_REG_CTRL);
+ ctrl &= ~ARCH_TIMER_CTRL_ENABLE;
+ arch_timer_reg_write(access, ARCH_TIMER_REG_CTRL, ctrl);
+ break;
+ default:
+ break;
+ }
+}
+
+static void arch_timer_set_mode_virt(enum clock_event_mode mode,
+ struct clock_event_device *clk)
+{
+ timer_set_mode(ARCH_TIMER_VIRT_ACCESS, mode);
+}
+
+static void arch_timer_set_mode_phys(enum clock_event_mode mode,
+ struct clock_event_device *clk)
+{
+ timer_set_mode(ARCH_TIMER_PHYS_ACCESS, mode);
+}
+
+static inline void set_next_event(const int access, unsigned long evt)
+{
+ unsigned long ctrl;
+ ctrl = arch_timer_reg_read(access, ARCH_TIMER_REG_CTRL);
+ ctrl |= ARCH_TIMER_CTRL_ENABLE;
+ ctrl &= ~ARCH_TIMER_CTRL_IT_MASK;
+ arch_timer_reg_write(access, ARCH_TIMER_REG_TVAL, evt);
+ arch_timer_reg_write(access, ARCH_TIMER_REG_CTRL, ctrl);
+}
+
+static int arch_timer_set_next_event_virt(unsigned long evt,
+ struct clock_event_device *unused)
+{
+ set_next_event(ARCH_TIMER_VIRT_ACCESS, evt);
+ return 0;
+}
+
+static int arch_timer_set_next_event_phys(unsigned long evt,
+ struct clock_event_device *unused)
+{
+ set_next_event(ARCH_TIMER_PHYS_ACCESS, evt);
+ return 0;
+}
+
+static int __cpuinit arch_timer_setup(struct clock_event_device *clk)
+{
+ clk->features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_C3STOP;
+ clk->name = "arch_sys_timer";
+ clk->rating = 450;
+ if (arch_timer_use_virtual) {
+ clk->irq = arch_timer_ppi[VIRT_PPI];
+ clk->set_mode = arch_timer_set_mode_virt;
+ clk->set_next_event = arch_timer_set_next_event_virt;
+ } else {
+ clk->irq = arch_timer_ppi[PHYS_SECURE_PPI];
+ clk->set_mode = arch_timer_set_mode_phys;
+ clk->set_next_event = arch_timer_set_next_event_phys;
+ }
+
+ clk->cpumask = cpumask_of(smp_processor_id());
+
+ clk->set_mode(CLOCK_EVT_MODE_SHUTDOWN, NULL);
+
+ clockevents_config_and_register(clk, arch_timer_rate,
+ 0xf, 0x7fffffff);
+
+ if (arch_timer_use_virtual)
+ enable_percpu_irq(arch_timer_ppi[VIRT_PPI], 0);
+ else {
+ enable_percpu_irq(arch_timer_ppi[PHYS_SECURE_PPI], 0);
+ if (arch_timer_ppi[PHYS_NONSECURE_PPI])
+ enable_percpu_irq(arch_timer_ppi[PHYS_NONSECURE_PPI], 0);
+ }
+
+ arch_counter_set_user_access();
+
+ return 0;
+}
+
+static int arch_timer_available(void)
+{
+ u32 freq;
+
+ if (arch_timer_rate == 0) {
+ freq = arch_timer_get_cntfrq();
+
+ /* Check the timer frequency. */
+ if (freq == 0) {
+ pr_warn("Architected timer frequency not available\n");
+ return -EINVAL;
+ }
+
+ arch_timer_rate = freq;
+ }
+
+ pr_info_once("Architected local timer running at %lu.%02luMHz (%s).\n",
+ (unsigned long)arch_timer_rate / 1000000,
+ (unsigned long)(arch_timer_rate / 10000) % 100,
+ arch_timer_use_virtual ? "virt" : "phys");
+ return 0;
+}
+
+u32 arch_timer_get_rate(void)
+{
+ return arch_timer_rate;
+}
+
+/*
+ * Some external users of arch_timer_read_counter (e.g. sched_clock) may try to
+ * call it before it has been initialised. Rather than incur a performance
+ * penalty checking for initialisation, provide a default implementation that
+ * won't lead to time appearing to jump backwards.
+ */
+static u64 arch_timer_read_zero(void)
+{
+ return 0;
+}
+
+u64 (*arch_timer_read_counter)(void) = arch_timer_read_zero;
+
+static cycle_t arch_counter_read(struct clocksource *cs)
+{
+ return arch_timer_read_counter();
+}
+
+static cycle_t arch_counter_read_cc(const struct cyclecounter *cc)
+{
+ return arch_timer_read_counter();
+}
+
+static struct clocksource clocksource_counter = {
+ .name = "arch_sys_counter",
+ .rating = 400,
+ .read = arch_counter_read,
+ .mask = CLOCKSOURCE_MASK(56),
+ .flags = CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+static struct cyclecounter cyclecounter = {
+ .read = arch_counter_read_cc,
+ .mask = CLOCKSOURCE_MASK(56),
+};
+
+static struct timecounter timecounter;
+
+struct timecounter *arch_timer_get_timecounter(void)
+{
+ return &timecounter;
+}
+
+static void __cpuinit arch_timer_stop(struct clock_event_device *clk)
+{
+ pr_debug("arch_timer_teardown disable IRQ%d cpu #%d\n",
+ clk->irq, smp_processor_id());
+
+ if (arch_timer_use_virtual)
+ disable_percpu_irq(arch_timer_ppi[VIRT_PPI]);
+ else {
+ disable_percpu_irq(arch_timer_ppi[PHYS_SECURE_PPI]);
+ if (arch_timer_ppi[PHYS_NONSECURE_PPI])
+ disable_percpu_irq(arch_timer_ppi[PHYS_NONSECURE_PPI]);
+ }
+
+ clk->set_mode(CLOCK_EVT_MODE_UNUSED, clk);
+}
+
+static int __cpuinit arch_timer_cpu_notify(struct notifier_block *self,
+ unsigned long action, void *hcpu)
+{
+ struct clock_event_device *evt = this_cpu_ptr(arch_timer_evt);
+
+ switch (action & ~CPU_TASKS_FROZEN) {
+ case CPU_STARTING:
+ arch_timer_setup(evt);
+ break;
+ case CPU_DYING:
+ arch_timer_stop(evt);
+ break;
+ }
+
+ return NOTIFY_OK;
+}
+
+static struct notifier_block arch_timer_cpu_nb __cpuinitdata = {
+ .notifier_call = arch_timer_cpu_notify,
+};
+
+static int __init arch_timer_register(void)
+{
+ int err;
+ int ppi;
+
+ err = arch_timer_available();
+ if (err)
+ goto out;
+
+ arch_timer_evt = alloc_percpu(struct clock_event_device);
+ if (!arch_timer_evt) {
+ err = -ENOMEM;
+ goto out;
+ }
+
+ clocksource_register_hz(&clocksource_counter, arch_timer_rate);
+ cyclecounter.mult = clocksource_counter.mult;
+ cyclecounter.shift = clocksource_counter.shift;
+ timecounter_init(&timecounter, &cyclecounter,
+ arch_counter_get_cntpct());
+
+ if (arch_timer_use_virtual) {
+ ppi = arch_timer_ppi[VIRT_PPI];
+ err = request_percpu_irq(ppi, arch_timer_handler_virt,
+ "arch_timer", arch_timer_evt);
+ } else {
+ ppi = arch_timer_ppi[PHYS_SECURE_PPI];
+ err = request_percpu_irq(ppi, arch_timer_handler_phys,
+ "arch_timer", arch_timer_evt);
+ if (!err && arch_timer_ppi[PHYS_NONSECURE_PPI]) {
+ ppi = arch_timer_ppi[PHYS_NONSECURE_PPI];
+ err = request_percpu_irq(ppi, arch_timer_handler_phys,
+ "arch_timer", arch_timer_evt);
+ if (err)
+ free_percpu_irq(arch_timer_ppi[PHYS_SECURE_PPI],
+ arch_timer_evt);
+ }
+ }
+
+ if (err) {
+ pr_err("arch_timer: can't register interrupt %d (%d)\n",
+ ppi, err);
+ goto out_free;
+ }
+
+ err = register_cpu_notifier(&arch_timer_cpu_nb);
+ if (err)
+ goto out_free_irq;
+
+ /* Immediately configure the timer on the boot CPU */
+ arch_timer_setup(this_cpu_ptr(arch_timer_evt));
+
+ return 0;
+
+out_free_irq:
+ if (arch_timer_use_virtual)
+ free_percpu_irq(arch_timer_ppi[VIRT_PPI], arch_timer_evt);
+ else {
+ free_percpu_irq(arch_timer_ppi[PHYS_SECURE_PPI],
+ arch_timer_evt);
+ if (arch_timer_ppi[PHYS_NONSECURE_PPI])
+ free_percpu_irq(arch_timer_ppi[PHYS_NONSECURE_PPI],
+ arch_timer_evt);
+ }
+
+out_free:
+ free_percpu(arch_timer_evt);
+out:
+ return err;
+}
+
+static const struct of_device_id arch_timer_of_match[] __initconst = {
+ { .compatible = "arm,armv7-timer", },
+ {},
+};
+
+int __init arch_timer_init(void)
+{
+ struct device_node *np;
+ u32 freq;
+ int i;
+
+ np = of_find_matching_node(NULL, arch_timer_of_match);
+ if (!np) {
+ pr_err("arch_timer: can't find DT node\n");
+ return -ENODEV;
+ }
+
+ /* Try to determine the frequency from the device tree or CNTFRQ */
+ if (!of_property_read_u32(np, "clock-frequency", &freq))
+ arch_timer_rate = freq;
+
+ for (i = PHYS_SECURE_PPI; i < MAX_TIMER_PPI; i++)
+ arch_timer_ppi[i] = irq_of_parse_and_map(np, i);
+
+ of_node_put(np);
+
+ /*
+ * If no interrupt provided for virtual timer, we'll have to
+ * stick to the physical timer. It'd better be accessible...
+ */
+ if (!arch_timer_ppi[VIRT_PPI]) {
+ arch_timer_use_virtual = false;
+
+ if (!arch_timer_ppi[PHYS_SECURE_PPI] ||
+ !arch_timer_ppi[PHYS_NONSECURE_PPI]) {
+ pr_warn("arch_timer: No interrupt available, giving up\n");
+ return -EINVAL;
+ }
+ }
+
+ if (arch_timer_use_virtual)
+ arch_timer_read_counter = arch_counter_get_cntvct;
+ else
+ arch_timer_read_counter = arch_counter_get_cntpct;
+
+ return arch_timer_register();
+}
--- /dev/null
+/*
+ * Copyright (C) 2012 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef __CLKSOURCE_ARM_ARCH_TIMER_H
+#define __CLKSOURCE_ARM_ARCH_TIMER_H
+
+#include <linux/clocksource.h>
+#include <linux/types.h>
+
+#define ARCH_TIMER_CTRL_ENABLE (1 << 0)
+#define ARCH_TIMER_CTRL_IT_MASK (1 << 1)
+#define ARCH_TIMER_CTRL_IT_STAT (1 << 2)
+
+#define ARCH_TIMER_REG_CTRL 0
+#define ARCH_TIMER_REG_TVAL 1
+
+#define ARCH_TIMER_PHYS_ACCESS 0
+#define ARCH_TIMER_VIRT_ACCESS 1
+
+#ifdef CONFIG_ARM_ARCH_TIMER
+
+extern int arch_timer_init(void);
+extern u32 arch_timer_get_rate(void);
+extern u64 (*arch_timer_read_counter)(void);
+extern struct timecounter *arch_timer_get_timecounter(void);
+
+#else
+
+static inline int arch_timer_init(void)
+{
+ return -ENXIO;
+}
+
+static inline u32 arch_timer_get_rate(void)
+{
+ return 0;
+}
+
+static inline u64 arch_timer_read_counter(void)
+{
+ return 0;
+}
+
+static struct timecounter *arch_timer_get_timecounter(void)
+{
+ return NULL;
+}
+
+#endif
+
+#endif
projects / linux-imx.git / commitdiff