-/*
- * Redeclare until I get around mopping the timer code insanity on MIPS.
- */
-extern int null_perf_irq(void);
-
-extern int (*perf_irq)(void);
-
-/*
- * 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;
-}
-
-irqreturn_t mips_timer_interrupt(int irq, void *dev_id)
-{
- int cpu = smp_processor_id();
-
-#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
- * IXMT set. Whichever TC gets the interrupt needs to
- * send special interprocessor interrupts to the other
- * TCs to make sure that they schedule, etc.
- *
- * That code is specific to the SMTC kernel, not to
- * the a particular platform, so it's invoked from
- * the general MIPS timer_interrupt routine.
- */
-
- /*
- * We could be here due to timer interrupt,
- * perf counter overflow, or both.
- */
- (void) handle_perf_irq(1);
-
- if (read_c0_cause() & (1 << 30)) {
- /*
- * 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);
- } else {
- write_c0_compare(read_c0_count() +
- (mips_hpt_frequency/HZ));
- local_timer_interrupt(irq, dev_id);
- }
- smtc_timer_broadcast();
- }
-#else /* CONFIG_MIPS_MT_SMTC */
- int r2 = cpu_has_mips_r2;
-
- if (handle_perf_irq(r2))
- goto out;
-
- if (r2 && ((read_c0_cause() & (1 << 30)) == 0))
- goto out;
-
- if (cpu == 0) {
- /*
- * CPU 0 handles the global timer interrupt job and process
- * accounting resets count/compare registers to trigger next
- * timer int.
- */
- timer_interrupt(irq, NULL);
- } else {
- /* Everyone else needs to reset the timer int here as
- ll_local_timer_interrupt doesn't */
- /*
- * FIXME: need to cope with counter underflow.
- * More support needs to be added to kernel/time for
- * counter/timer interrupts on multiple CPU's
- */
- write_c0_compare(read_c0_count() + (mips_hpt_frequency/HZ));
-
- /*
- * Other CPUs should do profiling and process accounting
- */
- local_timer_interrupt(irq, dev_id);
- }
-out:
-#endif /* CONFIG_MIPS_MT_SMTC */
- return IRQ_HANDLED;
-}
-