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--- a/arch/mips/kernel/cevt-r4k.c
+++ b/arch/mips/kernel/cevt-r4k.c
@@ -16,6 +16,22 @@
#include <asm/cevt-r4k.h>
/*
+ * Compare interrupt can be routed and latched outside the core,
+ * so a single execution hazard barrier may not be enough to give
+ * it time to clear as seen in the Cause register. 4 time the
+ * pipeline depth seems reasonably conservative, and empirically
+ * works better in configurations with high CPU/bus clock ratios.
+ */
+
+#define compare_change_hazard() \
+ do { \
+ irq_disable_hazard(); \
+ irq_disable_hazard(); \
+ irq_disable_hazard(); \
+ irq_disable_hazard(); \
+ } while (0)
+
+/*
* The SMTC Kernel for the 34K, 1004K, et. al. replaces several
* of these routines with SMTC-specific variants.
*/
@@ -31,6 +47,7 @@ static int mips_next_event(unsigned long
cnt = read_c0_count();
cnt += delta;
write_c0_compare(cnt);
+ compare_change_hazard();
res = ((int)(read_c0_count() - cnt) > 0) ? -ETIME : 0;
return res;
}
@@ -100,22 +117,6 @@ static int c0_compare_int_pending(void)
return (read_c0_cause() >> cp0_compare_irq_shift) & (1ul << CAUSEB_IP);
}
-/*
- * Compare interrupt can be routed and latched outside the core,
- * so a single execution hazard barrier may not be enough to give
- * it time to clear as seen in the Cause register. 4 time the
- * pipeline depth seems reasonably conservative, and empirically
- * works better in configurations with high CPU/bus clock ratios.
- */
-
-#define compare_change_hazard() \
- do { \
- irq_disable_hazard(); \
- irq_disable_hazard(); \
- irq_disable_hazard(); \
- irq_disable_hazard(); \
- } while (0)
-
int c0_compare_int_usable(void)
{
unsigned int delta;
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