]> nv-tegra.nvidia Code Review - linux-3.10.git/commitdiff
[MIPS] time: SMP/NUMA-proofing of IP27 HUB RT timer code.
authorRalf Baechle <ralf@linux-mips.org>
Mon, 22 Oct 2007 09:34:13 +0000 (10:34 +0100)
committerRalf Baechle <ralf@linux-mips.org>
Mon, 22 Oct 2007 21:09:00 +0000 (22:09 +0100)
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
arch/mips/sgi-ip27/ip27-init.c
arch/mips/sgi-ip27/ip27-timer.c

index 681b593071cbced9405d9b5cb691405f4b2f1ff6..3305fa9ae66d7bec7b5072e9672c1b9e787f0bf7 100644 (file)
@@ -110,7 +110,7 @@ static void __init per_hub_init(cnodeid_t cnode)
        }
 }
 
-void __init per_cpu_init(void)
+void __cpuinit per_cpu_init(void)
 {
        int cpu = smp_processor_id();
        int slice = LOCAL_HUB_L(PI_CPU_NUM);
index d467bf4f6c3f109be78d5857c007baa55ff57531..f5dccf01da115adb516adfc451c770439262fe54 100644 (file)
@@ -111,8 +111,24 @@ unsigned long read_persistent_clock(void)
         return mktime(year, month, date, hour, min, sec);
 }
 
-static int rt_set_next_event(unsigned long delta,
-               struct clock_event_device *evt)
+static void enable_rt_irq(unsigned int irq)
+{
+}
+
+static void disable_rt_irq(unsigned int irq)
+{
+}
+
+static struct irq_chip rt_irq_type = {
+       .name           = "SN HUB RT timer",
+       .ack            = disable_rt_irq,
+       .mask           = disable_rt_irq,
+       .mask_ack       = disable_rt_irq,
+       .unmask         = enable_rt_irq,
+       .eoi            = enable_rt_irq,
+};
+
+static int rt_next_event(unsigned long delta, struct clock_event_device *evt)
 {
        unsigned int cpu = smp_processor_id();
        int slice = cputoslice(cpu) == 0;
@@ -129,50 +145,24 @@ static void rt_set_mode(enum clock_event_mode mode,
                struct clock_event_device *evt)
 {
        switch (mode) {
-       case CLOCK_EVT_MODE_PERIODIC:
+       case CLOCK_EVT_MODE_ONESHOT:
                /* The only mode supported */
                break;
 
+       case CLOCK_EVT_MODE_PERIODIC:
        case CLOCK_EVT_MODE_UNUSED:
        case CLOCK_EVT_MODE_SHUTDOWN:
-       case CLOCK_EVT_MODE_ONESHOT:
        case CLOCK_EVT_MODE_RESUME:
                /* Nothing to do  */
                break;
        }
 }
 
-struct clock_event_device rt_clock_event_device = {
-       .name           = "HUB-RT",
-       .features       = CLOCK_EVT_FEAT_ONESHOT,
-
-       .rating         = 300,
-       .set_next_event = rt_set_next_event,
-       .set_mode       = rt_set_mode,
-};
-
-static void enable_rt_irq(unsigned int irq)
-{
-}
-
-static void disable_rt_irq(unsigned int irq)
-{
-}
-
-static struct irq_chip rt_irq_type = {
-       .name           = "SN HUB RT timer",
-       .ack            = disable_rt_irq,
-       .mask           = disable_rt_irq,
-       .mask_ack       = disable_rt_irq,
-       .unmask         = enable_rt_irq,
-       .eoi            = enable_rt_irq,
-};
-
 unsigned int rt_timer_irq;
 
-static irqreturn_t ip27_rt_timer_interrupt(int irq, void *dev_id)
+static irqreturn_t hub_rt_counter_handler(int irq, void *dev_id)
 {
-       struct clock_event_device *cd = &rt_clock_event_device;
+       struct clock_event_device *cd = dev_id;
        unsigned int cpu = smp_processor_id();
        int slice = cputoslice(cpu) == 0;
 
@@ -182,11 +172,10 @@ static irqreturn_t ip27_rt_timer_interrupt(int irq, void *dev_id)
        return IRQ_HANDLED;
 }
 
-static struct irqaction rt_irqaction = {
-       .handler        = (irq_handler_t) ip27_rt_timer_interrupt,
-       .flags          = IRQF_DISABLED,
-       .mask           = CPU_MASK_NONE,
-       .name           = "timer"
+struct irqaction hub_rt_irqaction = {
+       .handler        = hub_rt_counter_handler,
+       .flags          = IRQF_DISABLED | IRQF_PERCPU,
+       .name           = "hub-rt",
 };
 
 /*
@@ -200,32 +189,48 @@ static struct irqaction rt_irqaction = {
 #define NSEC_PER_CYCLE         800
 #define CYCLES_PER_SEC         (NSEC_PER_SEC / NSEC_PER_CYCLE)
 
-static void __init ip27_rt_clock_event_init(void)
+static DEFINE_PER_CPU(struct clock_event_device, hub_rt_clockevent);
+static DEFINE_PER_CPU(char [11], hub_rt_name);
+
+static void __cpuinit hub_rt_clock_event_init(void)
 {
-       struct clock_event_device *cd = &rt_clock_event_device;
        unsigned int cpu = smp_processor_id();
-       int irq = allocate_irqno();
-
-       if (irq < 0)
-               panic("Can't allocate interrupt number for timer interrupt");
-
-       rt_timer_irq = irq;
-
+       struct clock_event_device *cd = &per_cpu(hub_rt_clockevent, cpu);
+       unsigned char *name = per_cpu(hub_rt_name, cpu);
+       int irq = rt_timer_irq;
+
+       sprintf(name, "hub-rt %d", cpu);
+       cd->name                = "HUB-RT",
+       cd->features            = CLOCK_EVT_FEAT_ONESHOT,
+       clockevent_set_clock(cd, CYCLES_PER_SEC);
+       cd->max_delta_ns        = clockevent_delta2ns(0xfffffffffffff, cd);
+       cd->min_delta_ns        = clockevent_delta2ns(0x300, cd);
+       cd->rating              = 200,
        cd->irq                 = irq,
        cd->cpumask             = cpumask_of_cpu(cpu),
-
-       /*
-        * Calculate the min / max delta
-        */
-       cd->mult                =
-               div_sc((unsigned long) CYCLES_PER_SEC, 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->set_next_event      = rt_next_event,
+       cd->set_mode            = rt_set_mode,
        clockevents_register_device(cd);
+}
+
+static void __init hub_rt_clock_event_global_init(void)
+{
+       unsigned int irq;
+
+       do {
+               smp_wmb();
+               irq = rt_timer_irq;
+               if (irq)
+                       break;
+
+               irq = allocate_irqno();
+               if (irq < 0)
+                       panic("Allocation of irq number for timer failed");
+       } while (xchg(&rt_timer_irq, irq));
 
        set_irq_chip_and_handler(irq, &rt_irq_type, handle_percpu_irq);
-       setup_irq(irq, &rt_irqaction);
+       setup_irq(irq, &hub_rt_irqaction);
 }
 
 static cycle_t hub_rt_read(void)
@@ -233,27 +238,29 @@ static cycle_t hub_rt_read(void)
        return REMOTE_HUB_L(cputonasid(0), PI_RT_COUNT);
 }
 
-struct clocksource ht_rt_clocksource = {
+struct clocksource hub_rt_clocksource = {
        .name   = "HUB-RT",
        .rating = 200,
        .read   = hub_rt_read,
        .mask   = CLOCKSOURCE_MASK(52),
-       .shift  = 32,
        .flags  = CLOCK_SOURCE_IS_CONTINUOUS,
 };
 
-static void __init ip27_rt_clocksource_init(void)
+static void __init hub_rt_clocksource_init(void)
 {
-       clocksource_register(&ht_rt_clocksource);
+       struct clocksource *cs = &hub_rt_clocksource;
+
+       clocksource_set_clock(cs, CYCLES_PER_SEC);
+       clocksource_register(cs);
 }
 
 void __init plat_time_init(void)
 {
-       ip27_rt_clock_event_init();
-       ip27_rt_clocksource_init();
+       hub_rt_clocksource_init();
+       hub_rt_clock_event_global_init();
 }
 
-void __init cpu_time_init(void)
+void __cpuinit cpu_time_init(void)
 {
        lboard_t *board;
        klcpu_t *cpu;
@@ -271,6 +278,7 @@ void __init cpu_time_init(void)
 
        printk("CPU %d clock is %dMHz.\n", smp_processor_id(), cpu->cpu_speed);
 
+       hub_rt_clock_event_init();
        set_c0_status(SRB_TIMOCLK);
 }