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-rw-r--r--arch/mips/mips-boards/generic/time.c57
1 files changed, 36 insertions, 21 deletions
diff --git a/arch/mips/mips-boards/generic/time.c b/arch/mips/mips-boards/generic/time.c
index 557bf961f36a..de5798e1e015 100644
--- a/arch/mips/mips-boards/generic/time.c
+++ b/arch/mips/mips-boards/generic/time.c
@@ -92,10 +92,9 @@ extern int (*perf_irq)(struct pt_regs *regs);
irqreturn_t mips_timer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
{
int cpu = smp_processor_id();
- int r2 = cpu_has_mips_r2;
#ifdef CONFIG_MIPS_MT_SMTC
- /*
+ /*
* In an SMTC system, one Count/Compare set exists per VPE.
* Which TC within a VPE gets the interrupt is essentially
* random - we only know that it shouldn't be one with
@@ -108,29 +107,46 @@ irqreturn_t mips_timer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
* the general MIPS timer_interrupt routine.
*/
+ int vpflags;
+
/*
- * DVPE is necessary so long as cross-VPE interrupts
- * are done via read-modify-write of Cause register.
+ * We could be here due to timer interrupt,
+ * perf counter overflow, or both.
*/
- int vpflags = dvpe();
- write_c0_compare (read_c0_count() - 1);
- clear_c0_cause(CPUCTR_IMASKBIT);
- evpe(vpflags);
-
- if (cpu_data[cpu].vpe_id == 0) {
- timer_interrupt(irq, dev_id, regs);
- scroll_display_message();
- } else
- write_c0_compare (read_c0_count() + ( mips_hpt_frequency/HZ));
- smtc_timer_broadcast(cpu_data[cpu].vpe_id);
+ if (read_c0_cause() & (1 << 26))
+ perf_irq(regs);
- if (cpu != 0)
+ if (read_c0_cause() & (1 << 30)) {
+ /* If timer interrupt, make it de-assert */
+ write_c0_compare (read_c0_count() - 1);
/*
- * Other CPUs should do profiling and process accounting
+ * DVPE is necessary so long as cross-VPE interrupts
+ * are done via read-modify-write of Cause register.
*/
- local_timer_interrupt(irq, dev_id, regs);
-
+ vpflags = dvpe();
+ clear_c0_cause(CPUCTR_IMASKBIT);
+ evpe(vpflags);
+ /*
+ * There are things we only want to do once per tick
+ * in an "MP" system. One TC of each VPE will take
+ * the actual timer interrupt. The others will get
+ * timer broadcast IPIs. We use whoever it is that takes
+ * the tick on VPE 0 to run the full timer_interrupt().
+ */
+ if (cpu_data[cpu].vpe_id == 0) {
+ timer_interrupt(irq, NULL, regs);
+ smtc_timer_broadcast(cpu_data[cpu].vpe_id);
+ scroll_display_message();
+ } else {
+ write_c0_compare(read_c0_count() +
+ (mips_hpt_frequency/HZ));
+ local_timer_interrupt(irq, dev_id, regs);
+ smtc_timer_broadcast(cpu_data[cpu].vpe_id);
+ }
+ }
#else /* CONFIG_MIPS_MT_SMTC */
+ int r2 = cpu_has_mips_r2;
+
if (cpu == 0) {
/*
* CPU 0 handles the global timer interrupt job and process
@@ -161,9 +177,8 @@ irqreturn_t mips_timer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
*/
local_timer_interrupt(irq, dev_id, regs);
}
-#endif /* CONFIG_MIPS_MT_SMTC */
-
out:
+#endif /* CONFIG_MIPS_MT_SMTC */
return IRQ_HANDLED;
}