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path: root/target/linux/ramips/patches-2.6.30/002-mips-clocksource-init-war.patch
blob: 03a66ff1330c1b5566ad0819e2e76c646fe0f3be (plain)
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--- a/arch/mips/kernel/cevt-r4k.c
+++ b/arch/mips/kernel/cevt-r4k.c
@@ -15,6 +15,22 @@
 #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.
  */
@@ -30,6 +46,7 @@ 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;
 }
@@ -99,22 +116,6 @@ static int c0_compare_int_pending(void)
 	return (read_c0_cause() >> cp0_compare_irq) & 0x100;
 }
 
-/*
- * 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;