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Diffstat (limited to 'arch/mips/kernel/cevt-r4k.c')
-rw-r--r--arch/mips/kernel/cevt-r4k.c202
1 files changed, 60 insertions, 142 deletions
diff --git a/arch/mips/kernel/cevt-r4k.c b/arch/mips/kernel/cevt-r4k.c
index 24a2d907aa0..bc127e22fda 100644
--- a/arch/mips/kernel/cevt-r4k.c
+++ b/arch/mips/kernel/cevt-r4k.c
@@ -9,70 +9,36 @@
#include <linux/clockchips.h>
#include <linux/interrupt.h>
#include <linux/percpu.h>
+#include <linux/smp.h>
+#include <linux/irq.h>
-#include <asm/smtc_ipi.h>
#include <asm/time.h>
+#include <asm/cevt-r4k.h>
+#include <asm/gic.h>
static int mips_next_event(unsigned long delta,
- struct clock_event_device *evt)
+ struct clock_event_device *evt)
{
unsigned int cnt;
int res;
-#ifdef CONFIG_MIPS_MT_SMTC
- {
- unsigned long flags, vpflags;
- local_irq_save(flags);
- vpflags = dvpe();
-#endif
cnt = read_c0_count();
cnt += delta;
write_c0_compare(cnt);
- res = ((int)(read_c0_count() - cnt) > 0) ? -ETIME : 0;
-#ifdef CONFIG_MIPS_MT_SMTC
- evpe(vpflags);
- local_irq_restore(flags);
- }
-#endif
+ res = ((int)(read_c0_count() - cnt) >= 0) ? -ETIME : 0;
return res;
}
-static void mips_set_mode(enum clock_event_mode mode,
- struct clock_event_device *evt)
+void mips_set_clock_mode(enum clock_event_mode mode,
+ struct clock_event_device *evt)
{
/* Nothing to do ... */
}
-static DEFINE_PER_CPU(struct clock_event_device, mips_clockevent_device);
-static int cp0_timer_irq_installed;
-
-/*
- * Timer ack for an R4k-compatible timer of a known frequency.
- */
-static void c0_timer_ack(void)
-{
- write_c0_compare(read_c0_compare());
-}
-
-/*
- * Possibly handle a performance counter interrupt.
- * Return true if the timer interrupt should not be checked
- */
-static inline int handle_perf_irq(int r2)
-{
- /*
- * The performance counter overflow interrupt may be shared with the
- * timer interrupt (cp0_perfcount_irq < 0). If it is and a
- * performance counter has overflowed (perf_irq() == IRQ_HANDLED)
- * and we can't reliably determine if a counter interrupt has also
- * happened (!r2) then don't check for a timer interrupt.
- */
- return (cp0_perfcount_irq < 0) &&
- perf_irq() == IRQ_HANDLED &&
- !r2;
-}
+DEFINE_PER_CPU(struct clock_event_device, mips_clockevent_device);
+int cp0_timer_irq_installed;
-static irqreturn_t c0_compare_interrupt(int irq, void *dev_id)
+irqreturn_t c0_compare_interrupt(int irq, void *dev_id)
{
const int r2 = cpu_has_mips_r2;
struct clock_event_device *cd;
@@ -88,17 +54,13 @@ static irqreturn_t c0_compare_interrupt(int irq, void *dev_id)
goto out;
/*
- * The same applies to performance counter interrupts. But with the
+ * The same applies to performance counter interrupts. But with the
* above we now know that the reason we got here must be a timer
* interrupt. Being the paranoiacs we are we check anyway.
*/
if (!r2 || (read_c0_cause() & (1 << 30))) {
- c0_timer_ack();
-#ifdef CONFIG_MIPS_MT_SMTC
- if (cpu_data[cpu].vpe_id)
- goto out;
- cpu = 0;
-#endif
+ /* Clear Count/Compare Interrupt */
+ write_c0_compare(read_c0_compare());
cd = &per_cpu(mips_clockevent_device, cpu);
cd->event_handler(cd);
}
@@ -107,65 +69,14 @@ out:
return IRQ_HANDLED;
}
-static struct irqaction c0_compare_irqaction = {
+struct irqaction c0_compare_irqaction = {
.handler = c0_compare_interrupt,
-#ifdef CONFIG_MIPS_MT_SMTC
- .flags = IRQF_DISABLED,
-#else
- .flags = IRQF_DISABLED | IRQF_PERCPU,
-#endif
+ .flags = IRQF_PERCPU | IRQF_TIMER,
.name = "timer",
};
-#ifdef CONFIG_MIPS_MT_SMTC
-DEFINE_PER_CPU(struct clock_event_device, smtc_dummy_clockevent_device);
-
-static void smtc_set_mode(enum clock_event_mode mode,
- struct clock_event_device *evt)
-{
-}
-static void mips_broadcast(cpumask_t mask)
-{
- unsigned int cpu;
-
- for_each_cpu_mask(cpu, mask)
- smtc_send_ipi(cpu, SMTC_CLOCK_TICK, 0);
-}
-
-static void setup_smtc_dummy_clockevent_device(void)
-{
- //uint64_t mips_freq = mips_hpt_^frequency;
- unsigned int cpu = smp_processor_id();
- struct clock_event_device *cd;
-
- cd = &per_cpu(smtc_dummy_clockevent_device, cpu);
-
- cd->name = "SMTC";
- cd->features = CLOCK_EVT_FEAT_DUMMY;
-
- /* Calculate the min / max delta */
- cd->mult = 0; //div_sc((unsigned long) mips_freq, NSEC_PER_SEC, 32);
- cd->shift = 0; //32;
- cd->max_delta_ns = 0; //clockevent_delta2ns(0x7fffffff, cd);
- cd->min_delta_ns = 0; //clockevent_delta2ns(0x30, cd);
-
- cd->rating = 200;
- cd->irq = 17; //-1;
-// if (cpu)
-// cd->cpumask = CPU_MASK_ALL; // cpumask_of_cpu(cpu);
-// else
- cd->cpumask = cpumask_of_cpu(cpu);
-
- cd->set_mode = smtc_set_mode;
-
- cd->broadcast = mips_broadcast;
-
- clockevents_register_device(cd);
-}
-#endif
-
-static void mips_event_handler(struct clock_event_device *dev)
+void mips_event_handler(struct clock_event_device *dev)
{
}
@@ -174,20 +85,39 @@ static void mips_event_handler(struct clock_event_device *dev)
*/
static int c0_compare_int_pending(void)
{
- return (read_c0_cause() >> cp0_compare_irq) & 0x100;
+#ifdef CONFIG_IRQ_GIC
+ if (cpu_has_veic)
+ return gic_get_timer_pending();
+#endif
+ return (read_c0_cause() >> cp0_compare_irq_shift) & (1ul << CAUSEB_IP);
}
-static int c0_compare_int_usable(void)
+/*
+ * Compare interrupt can be routed and latched outside the core,
+ * so wait up to worst case number of cycle counter ticks for timer interrupt
+ * changes to propagate to the cause register.
+ */
+#define COMPARE_INT_SEEN_TICKS 50
+
+int c0_compare_int_usable(void)
{
unsigned int delta;
unsigned int cnt;
+#ifdef CONFIG_KVM_GUEST
+ return 1;
+#endif
+
/*
- * IP7 already pending? Try to clear it by acking the timer.
+ * IP7 already pending? Try to clear it by acking the timer.
*/
if (c0_compare_int_pending()) {
- write_c0_compare(read_c0_count());
- irq_disable_hazard();
+ cnt = read_c0_count();
+ write_c0_compare(cnt);
+ back_to_back_c0_hazard();
+ while (read_c0_count() < (cnt + COMPARE_INT_SEEN_TICKS))
+ if (!c0_compare_int_pending())
+ break;
if (c0_compare_int_pending())
return 0;
}
@@ -196,7 +126,7 @@ static int c0_compare_int_usable(void)
cnt = read_c0_count();
cnt += delta;
write_c0_compare(cnt);
- irq_disable_hazard();
+ back_to_back_c0_hazard();
if ((int)(read_c0_count() - cnt) < 0)
break;
/* increase delta if the timer was already expired */
@@ -205,11 +135,17 @@ static int c0_compare_int_usable(void)
while ((int)(read_c0_count() - cnt) <= 0)
; /* Wait for expiry */
+ while (read_c0_count() < (cnt + COMPARE_INT_SEEN_TICKS))
+ if (c0_compare_int_pending())
+ break;
if (!c0_compare_int_pending())
return 0;
-
- write_c0_compare(read_c0_count());
- irq_disable_hazard();
+ cnt = read_c0_count();
+ write_c0_compare(cnt);
+ back_to_back_c0_hazard();
+ while (read_c0_count() < (cnt + COMPARE_INT_SEEN_TICKS))
+ if (!c0_compare_int_pending())
+ break;
if (c0_compare_int_pending())
return 0;
@@ -219,9 +155,8 @@ static int c0_compare_int_usable(void)
return 1;
}
-int __cpuinit mips_clockevent_init(void)
+int r4k_clockevent_init(void)
{
- uint64_t mips_freq = mips_hpt_frequency;
unsigned int cpu = smp_processor_id();
struct clock_event_device *cd;
unsigned int irq;
@@ -229,17 +164,6 @@ int __cpuinit mips_clockevent_init(void)
if (!cpu_has_counter || !mips_hpt_frequency)
return -ENXIO;
-#ifdef CONFIG_MIPS_MT_SMTC
- setup_smtc_dummy_clockevent_device();
-
- /*
- * On SMTC we only register VPE0's compare interrupt as clockevent
- * device.
- */
- if (cpu)
- return 0;
-#endif
-
if (!c0_compare_int_usable())
return -ENXIO;
@@ -255,23 +179,21 @@ int __cpuinit mips_clockevent_init(void)
cd = &per_cpu(mips_clockevent_device, cpu);
cd->name = "MIPS";
- cd->features = CLOCK_EVT_FEAT_ONESHOT;
+ cd->features = CLOCK_EVT_FEAT_ONESHOT |
+ CLOCK_EVT_FEAT_C3STOP |
+ CLOCK_EVT_FEAT_PERCPU;
+
+ clockevent_set_clock(cd, mips_hpt_frequency);
/* Calculate the min / max delta */
- cd->mult = div_sc((unsigned long) mips_freq, NSEC_PER_SEC, 32);
- cd->shift = 32;
cd->max_delta_ns = clockevent_delta2ns(0x7fffffff, cd);
cd->min_delta_ns = clockevent_delta2ns(0x300, cd);
cd->rating = 300;
cd->irq = irq;
-#ifdef CONFIG_MIPS_MT_SMTC
- cd->cpumask = CPU_MASK_ALL;
-#else
- cd->cpumask = cpumask_of_cpu(cpu);
-#endif
+ cd->cpumask = cpumask_of(cpu);
cd->set_next_event = mips_next_event;
- cd->set_mode = mips_set_mode;
+ cd->set_mode = mips_set_clock_mode;
cd->event_handler = mips_event_handler;
clockevents_register_device(cd);
@@ -281,12 +203,8 @@ int __cpuinit mips_clockevent_init(void)
cp0_timer_irq_installed = 1;
-#ifdef CONFIG_MIPS_MT_SMTC
-#define CPUCTR_IMASKBIT (0x100 << cp0_compare_irq)
- setup_irq_smtc(irq, &c0_compare_irqaction, CPUCTR_IMASKBIT);
-#else
setup_irq(irq, &c0_compare_irqaction);
-#endif
return 0;
}
+