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Diffstat (limited to 'arch/sparc/kernel/pcic.c')
-rw-r--r--arch/sparc/kernel/pcic.c48
1 files changed, 26 insertions, 22 deletions
diff --git a/arch/sparc/kernel/pcic.c b/arch/sparc/kernel/pcic.c
index 6edec801e46a..118a3f5806a8 100644
--- a/arch/sparc/kernel/pcic.c
+++ b/arch/sparc/kernel/pcic.c
@@ -703,31 +703,28 @@ static void pcic_clear_clock_irq(void)
pcic_timer_dummy = readl(pcic0.pcic_regs+PCI_SYS_LIMIT);
}
-static irqreturn_t pcic_timer_handler (int irq, void *h)
+/* CPU frequency is 100 MHz, timer increments every 4 CPU clocks */
+#define USECS_PER_JIFFY (1000000 / HZ)
+#define TICK_TIMER_LIMIT ((100 * 1000000 / 4) / HZ)
+
+static unsigned int pcic_cycles_offset(void)
{
- pcic_clear_clock_irq();
- xtime_update(1);
-#ifndef CONFIG_SMP
- update_process_times(user_mode(get_irq_regs()));
-#endif
- return IRQ_HANDLED;
-}
+ u32 value, count;
-#define USECS_PER_JIFFY 10000 /* We have 100HZ "standard" timer for sparc */
-#define TICK_TIMER_LIMIT ((100*1000000/4)/100)
+ value = readl(pcic0.pcic_regs + PCI_SYS_COUNTER);
+ count = value & ~PCI_SYS_COUNTER_OVERFLOW;
-u32 pci_gettimeoffset(void)
-{
+ if (value & PCI_SYS_COUNTER_OVERFLOW)
+ count += TICK_TIMER_LIMIT;
/*
- * We divide all by 100
+ * We divide all by HZ
* to have microsecond resolution and to avoid overflow
*/
- unsigned long count =
- readl(pcic0.pcic_regs+PCI_SYS_COUNTER) & ~PCI_SYS_COUNTER_OVERFLOW;
- count = ((count/100)*USECS_PER_JIFFY) / (TICK_TIMER_LIMIT/100);
- return count * 1000;
-}
+ count = ((count / HZ) * USECS_PER_JIFFY) / (TICK_TIMER_LIMIT / HZ);
+ /* Coordinate with the fact that timer_cs rate is 2MHz */
+ return count * 2;
+}
void __init pci_time_init(void)
{
@@ -736,9 +733,16 @@ void __init pci_time_init(void)
int timer_irq, irq;
int err;
- do_arch_gettimeoffset = pci_gettimeoffset;
-
- btfixup();
+#ifndef CONFIG_SMP
+ /*
+ * It's in SBUS dimension, because timer_cs is in this dimension.
+ * We take into account this in pcic_cycles_offset()
+ */
+ timer_cs_period = SBUS_CLOCK_RATE / HZ;
+ sparc_config.features |= FEAT_L10_CLOCKEVENT;
+#endif
+ sparc_config.features |= FEAT_L10_CLOCKSOURCE;
+ sparc_config.get_cycles_offset = pcic_cycles_offset;
writel (TICK_TIMER_LIMIT, pcic->pcic_regs+PCI_SYS_LIMIT);
/* PROM should set appropriate irq */
@@ -747,7 +751,7 @@ void __init pci_time_init(void)
writel (PCI_COUNTER_IRQ_SET(timer_irq, 0),
pcic->pcic_regs+PCI_COUNTER_IRQ);
irq = pcic_build_device_irq(NULL, timer_irq);
- err = request_irq(irq, pcic_timer_handler,
+ err = request_irq(irq, timer_interrupt,
IRQF_TIMER, "timer", NULL);
if (err) {
prom_printf("time_init: unable to attach IRQ%d\n", timer_irq);
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