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-rw-r--r--arch/arm/kernel/arch_timer.c504
1 files changed, 20 insertions, 484 deletions
diff --git a/arch/arm/kernel/arch_timer.c b/arch/arm/kernel/arch_timer.c
index c8ef207..36ebcf4 100644
--- a/arch/arm/kernel/arch_timer.c
+++ b/arch/arm/kernel/arch_timer.c
@@ -9,516 +9,52 @@
* 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/cputype.h>
#include <asm/delay.h>
-#include <asm/localtimer.h>
-#include <asm/arch_timer.h>
-#include <asm/system_info.h>
#include <asm/sched_clock.h>
-static unsigned long 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.
- */
-
-#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_FREQ 1
-#define ARCH_TIMER_REG_TVAL 2
-
-#define ARCH_TIMER_PHYS_ACCESS 0
-#define ARCH_TIMER_VIRT_ACCESS 1
-
-/*
- * These register accessors are marked inline so the compiler can
- * nicely work out which register we want, and chuck away the rest of
- * the code. At least it does so with a recent GCC (4.6.3).
- */
-static inline void arch_timer_reg_write(const int access, const int reg, u32 val)
-{
- if (access == ARCH_TIMER_PHYS_ACCESS) {
- switch (reg) {
- case ARCH_TIMER_REG_CTRL:
- asm volatile("mcr p15, 0, %0, c14, c2, 1" : : "r" (val));
- break;
- case ARCH_TIMER_REG_TVAL:
- asm volatile("mcr p15, 0, %0, c14, c2, 0" : : "r" (val));
- break;
- }
- }
-
- if (access == ARCH_TIMER_VIRT_ACCESS) {
- switch (reg) {
- case ARCH_TIMER_REG_CTRL:
- asm volatile("mcr p15, 0, %0, c14, c3, 1" : : "r" (val));
- break;
- case ARCH_TIMER_REG_TVAL:
- asm volatile("mcr p15, 0, %0, c14, c3, 0" : : "r" (val));
- break;
- }
- }
-
- isb();
-}
-
-static inline u32 arch_timer_reg_read(const int access, const int reg)
-{
- u32 val = 0;
-
- if (access == ARCH_TIMER_PHYS_ACCESS) {
- switch (reg) {
- case ARCH_TIMER_REG_CTRL:
- asm volatile("mrc p15, 0, %0, c14, c2, 1" : "=r" (val));
- break;
- case ARCH_TIMER_REG_TVAL:
- asm volatile("mrc p15, 0, %0, c14, c2, 0" : "=r" (val));
- break;
- case ARCH_TIMER_REG_FREQ:
- asm volatile("mrc p15, 0, %0, c14, c0, 0" : "=r" (val));
- break;
- }
- }
-
- if (access == ARCH_TIMER_VIRT_ACCESS) {
- switch (reg) {
- case ARCH_TIMER_REG_CTRL:
- asm volatile("mrc p15, 0, %0, c14, c3, 1" : "=r" (val));
- break;
- case ARCH_TIMER_REG_TVAL:
- asm volatile("mrc p15, 0, %0, c14, c3, 0" : "=r" (val));
- break;
- }
- }
-
- return val;
-}
-
-static inline cycle_t arch_timer_counter_read(const int access)
-{
- cycle_t cval = 0;
-
- if (access == ARCH_TIMER_PHYS_ACCESS)
- asm volatile("mrrc p15, 0, %Q0, %R0, c14" : "=r" (cval));
-
- if (access == ARCH_TIMER_VIRT_ACCESS)
- asm volatile("mrrc p15, 1, %Q0, %R0, c14" : "=r" (cval));
-
- return cval;
-}
-
-static inline cycle_t arch_counter_get_cntpct(void)
-{
- return arch_timer_counter_read(ARCH_TIMER_PHYS_ACCESS);
-}
-
-static inline cycle_t arch_counter_get_cntvct(void)
-{
- return arch_timer_counter_read(ARCH_TIMER_VIRT_ACCESS);
-}
-
-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 = *(struct clock_event_device **)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 = *(struct clock_event_device **)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->set_mode(CLOCK_EVT_MODE_SHUTDOWN, NULL);
-
- clockevents_config_and_register(clk, arch_timer_rate,
- 0xf, 0x7fffffff);
-
- *__this_cpu_ptr(arch_timer_evt) = clk;
-
- 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);
- }
-
- return 0;
-}
-
-/* Is the optional system timer available? */
-static int local_timer_is_architected(void)
-{
- return (cpu_architecture() >= CPU_ARCH_ARMv7) &&
- ((read_cpuid_ext(CPUID_EXT_PFR1) >> 16) & 0xf) == 1;
-}
-
-static int arch_timer_available(void)
-{
- unsigned long freq;
-
- if (!local_timer_is_architected())
- return -ENXIO;
-
- if (arch_timer_rate == 0) {
- freq = arch_timer_reg_read(ARCH_TIMER_PHYS_ACCESS,
- ARCH_TIMER_REG_FREQ);
-
- /* 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",
- arch_timer_rate / 1000000, (arch_timer_rate / 10000) % 100,
- arch_timer_use_virtual ? "virt" : "phys");
- return 0;
-}
-
-static u32 notrace arch_counter_get_cntpct32(void)
-{
- cycle_t cnt = arch_counter_get_cntpct();
-
- /*
- * The sched_clock infrastructure only knows about counters
- * with at most 32bits. Forget about the upper 24 bits for the
- * time being...
- */
- return (u32)cnt;
-}
-
-static u32 notrace arch_counter_get_cntvct32(void)
-{
- cycle_t cnt = arch_counter_get_cntvct();
-
- /*
- * The sched_clock infrastructure only knows about counters
- * with at most 32bits. Forget about the upper 24 bits for the
- * time being...
- */
- return (u32)cnt;
-}
-
-static cycle_t arch_counter_read(struct clocksource *cs)
-{
- /*
- * Always use the physical counter for the clocksource.
- * CNTHCTL.PL1PCTEN must be set to 1.
- */
- return arch_counter_get_cntpct();
-}
-
-static unsigned long arch_timer_read_current_timer(void)
+static unsigned long arch_timer_read_counter_long(void)
{
- return arch_counter_get_cntpct();
+ return arch_timer_read_counter();
}
-static cycle_t arch_counter_read_cc(const struct cyclecounter *cc)
+static u32 arch_timer_read_counter_u32(void)
{
- /*
- * Always use the physical counter for the clocksource.
- * CNTHCTL.PL1PCTEN must be set to 1.
- */
- return arch_counter_get_cntpct();
+ 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 struct local_timer_ops arch_timer_ops __cpuinitdata = {
- .setup = arch_timer_setup,
- .stop = arch_timer_stop,
-};
-
-static struct clock_event_device arch_timer_global_evt;
+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 = local_timer_register(&arch_timer_ops);
- if (err) {
- /*
- * We couldn't register as a local timer (could be
- * because we're on a UP platform, or because some
- * other local timer is already present...). Try as a
- * global timer instead.
- */
- arch_timer_global_evt.cpumask = cpumask_of(0);
- err = arch_timer_setup(&arch_timer_global_evt);
- }
- if (err)
- goto out_free_irq;
-
/* 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;
- }
-
- /* 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);
+ int ret;
- /*
- * 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;
+ ret = arch_timer_init();
+ if (ret)
+ return ret;
- 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;
- }
- }
+ arch_timer_delay_timer_register();
- return arch_timer_register();
+ return 0;
}
int __init arch_timer_sched_clock_init(void)
{
- u32 (*cnt32)(void);
- int err;
-
- err = arch_timer_available();
- if (err)
- return err;
-
- if (arch_timer_use_virtual)
- cnt32 = arch_counter_get_cntvct32;
- else
- cnt32 = arch_counter_get_cntpct32;
+ if (arch_timer_get_rate() == 0)
+ return -ENXIO;
- setup_sched_clock(cnt32, 32, arch_timer_rate);
+ setup_sched_clock(arch_timer_read_counter_u32,
+ 32, arch_timer_get_rate());
return 0;
}