diff options
author | Arjan van de Ven <arjan@linux.intel.com> | 2008-10-17 09:20:26 -0700 |
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committer | Arjan van de Ven <arjan@linux.intel.com> | 2008-10-17 09:20:26 -0700 |
commit | 651dab4264e4ba0e563f5ff56f748127246e9065 (patch) | |
tree | 016630974bdcb00fe529b673f96d389e0fd6dc94 /arch/mips/kernel/cevt-r4k.c | |
parent | 40b8606253552109815786e5d4b0de98782d31f5 (diff) | |
parent | 2e532d68a2b3e2aa6b19731501222069735c741c (diff) |
Merge commit 'linus/master' into merge-linus
Conflicts:
arch/x86/kvm/i8254.c
Diffstat (limited to 'arch/mips/kernel/cevt-r4k.c')
-rw-r--r-- | arch/mips/kernel/cevt-r4k.c | 173 |
1 files changed, 48 insertions, 125 deletions
diff --git a/arch/mips/kernel/cevt-r4k.c b/arch/mips/kernel/cevt-r4k.c index 24a2d907aa0..4a4c59f2737 100644 --- a/arch/mips/kernel/cevt-r4k.c +++ b/arch/mips/kernel/cevt-r4k.c @@ -12,6 +12,14 @@ #include <asm/smtc_ipi.h> #include <asm/time.h> +#include <asm/cevt-r4k.h> + +/* + * The SMTC Kernel for the 34K, 1004K, et. al. replaces several + * of these routines with SMTC-specific variants. + */ + +#ifndef CONFIG_MIPS_MT_SMTC static int mips_next_event(unsigned long delta, struct clock_event_device *evt) @@ -19,60 +27,27 @@ static int mips_next_event(unsigned long delta, 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 return res; } -static void mips_set_mode(enum clock_event_mode mode, - struct clock_event_device *evt) +#endif /* CONFIG_MIPS_MT_SMTC */ + +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; +DEFINE_PER_CPU(struct clock_event_device, mips_clockevent_device); +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()); -} +#ifndef CONFIG_MIPS_MT_SMTC -/* - * 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; -} - -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; @@ -93,12 +68,8 @@ static irqreturn_t c0_compare_interrupt(int irq, void *dev_id) * 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 +78,16 @@ out: return IRQ_HANDLED; } -static struct irqaction c0_compare_irqaction = { +#endif /* Not CONFIG_MIPS_MT_SMTC */ + +struct irqaction c0_compare_irqaction = { .handler = c0_compare_interrupt, -#ifdef CONFIG_MIPS_MT_SMTC - .flags = IRQF_DISABLED, -#else .flags = IRQF_DISABLED | IRQF_PERCPU, -#endif .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) { } @@ -177,7 +99,23 @@ static int c0_compare_int_pending(void) return (read_c0_cause() >> cp0_compare_irq) & 0x100; } -static int c0_compare_int_usable(void) +/* + * Compare interrupt can be routed and latched outside the core, + * so a single execution hazard barrier may not be enough to give + * it time to clear as seen in the Cause register. 4 time the + * pipeline depth seems reasonably conservative, and empirically + * works better in configurations with high CPU/bus clock ratios. + */ + +#define compare_change_hazard() \ + do { \ + irq_disable_hazard(); \ + irq_disable_hazard(); \ + irq_disable_hazard(); \ + irq_disable_hazard(); \ + } while (0) + +int c0_compare_int_usable(void) { unsigned int delta; unsigned int cnt; @@ -187,7 +125,7 @@ static int c0_compare_int_usable(void) */ if (c0_compare_int_pending()) { write_c0_compare(read_c0_count()); - irq_disable_hazard(); + compare_change_hazard(); if (c0_compare_int_pending()) return 0; } @@ -196,7 +134,7 @@ static int c0_compare_int_usable(void) cnt = read_c0_count(); cnt += delta; write_c0_compare(cnt); - irq_disable_hazard(); + compare_change_hazard(); if ((int)(read_c0_count() - cnt) < 0) break; /* increase delta if the timer was already expired */ @@ -205,11 +143,12 @@ static int c0_compare_int_usable(void) while ((int)(read_c0_count() - cnt) <= 0) ; /* Wait for expiry */ + compare_change_hazard(); if (!c0_compare_int_pending()) return 0; write_c0_compare(read_c0_count()); - irq_disable_hazard(); + compare_change_hazard(); if (c0_compare_int_pending()) return 0; @@ -219,6 +158,8 @@ static int c0_compare_int_usable(void) return 1; } +#ifndef CONFIG_MIPS_MT_SMTC + int __cpuinit mips_clockevent_init(void) { uint64_t mips_freq = mips_hpt_frequency; @@ -229,17 +170,6 @@ 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; @@ -265,13 +195,9 @@ int __cpuinit mips_clockevent_init(void) 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->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 +207,9 @@ 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; } + +#endif /* Not CONFIG_MIPS_MT_SMTC */ |