1 files changed, 31 insertions, 14 deletions

diff --git a/arch/mips/kernel/cevt-r4k.c b/arch/mips/kernel/cevt-r4k.c
index ae2984fff580..bab935a3d74b 100644
--- a/arch/mips/kernel/cevt-r4k.c
+++ b/arch/mips/kernel/cevt-r4k.c
@@ -28,7 +28,7 @@ static int mips_next_event(unsigned long delta,
         cnt = read_c0_count();
         cnt += delta;
         write_c0_compare(cnt);
-        res = ((long)(read_c0_count() - cnt ) > 0) ? -ETIME : 0;
+        res = ((int)(read_c0_count() - cnt) > 0) ? -ETIME : 0;
 #ifdef CONFIG_MIPS_MT_SMTC
         evpe(vpflags);
         local_irq_restore(flags);
@@ -179,7 +179,7 @@ static int c0_compare_int_pending(void)
 
 static int c0_compare_int_usable(void)
 {
-        const unsigned int delta = 0x300000;
+        unsigned int delta;
         unsigned int cnt;
 
         /*
@@ -192,11 +192,17 @@ static int c0_compare_int_usable(void)
                         return 0;
         }
 
-        cnt = read_c0_count();
-        cnt += delta;
-        write_c0_compare(cnt);
+        for (delta = 0x10; delta <= 0x400000; delta <<= 1) {
+                cnt = read_c0_count();
+                cnt += delta;
+                write_c0_compare(cnt);
+                irq_disable_hazard();
+                if ((int)(read_c0_count() - cnt) < 0)
+                    break;
+                /* increase delta if the timer was already expired */
+        }
 
-        while ((long)(read_c0_count() - cnt) <= 0)
+        while ((int)(read_c0_count() - cnt) <= 0)
                 ;       /* Wait for expiry  */
 
         if (!c0_compare_int_pending())
@@ -218,9 +224,9 @@ void __cpuinit mips_clockevent_init(void)
         uint64_t mips_freq = mips_hpt_frequency;
         unsigned int cpu = smp_processor_id();
         struct clock_event_device *cd;
-        unsigned int irq = MIPS_CPU_IRQ_BASE + 7;
+        unsigned int irq;
 
-        if (!cpu_has_counter)
+        if (!cpu_has_counter || !mips_hpt_frequency)
                 return;
 
 #ifdef CONFIG_MIPS_MT_SMTC
@@ -237,6 +243,15 @@ void __cpuinit mips_clockevent_init(void)
         if (!c0_compare_int_usable())
                 return;
 
+        /*
+         * With vectored interrupts things are getting platform specific.
+         * get_c0_compare_int is a hook to allow a platform to return the
+         * interrupt number of it's liking.
+         */
+        irq = MIPS_CPU_IRQ_BASE + cp0_compare_irq;
+        if (get_c0_compare_int)
+                irq = get_c0_compare_int();
+
         cd = &per_cpu(mips_clockevent_device, cpu);
 
         cd->name                = "MIPS";
@@ -261,13 +276,15 @@ void __cpuinit mips_clockevent_init(void)
 
         clockevents_register_device(cd);
 
-        if (!cp0_timer_irq_installed) {
+        if (!cp0_timer_irq_installed)
+                return;
+
+        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);
+        setup_irq_smtc(irq, &c0_compare_irqaction, CPUCTR_IMASKBIT);
 #else
-                setup_irq(irq, &c0_compare_irqaction);
-#endif /* CONFIG_MIPS_MT_SMTC */
-                cp0_timer_irq_installed = 1;
-        }
+        setup_irq(irq, &c0_compare_irqaction);
+#endif
 }