Hello Ralf,
Whereas current implementation works, the modification below can protect
us from problems such as the pipeline hazards in vr41xx cpus without any
added extra code length. Also, I beleive Yoichi posted something similar
a few months ago.
Please apply.
Ricardo
---
Ack the IRQ by writing to c0_compare it's own value rather than the
c0_count value. This prevents issues caused by pipeline hazards, on
vr41xx for example.
Signed-off-by: Ricardo Mendoza <ricmm@xxxxxxxxxx>
---
arch/mips/kernel/cevt-r4k.c | 4 ++--
1 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/mips/kernel/cevt-r4k.c b/arch/mips/kernel/cevt-r4k.c
index 24a2d90..16e079c 100644
--- a/arch/mips/kernel/cevt-r4k.c
+++ b/arch/mips/kernel/cevt-r4k.c
@@ -186,7 +186,7 @@ static int c0_compare_int_usable(void)
* IP7 already pending? Try to clear it by acking the timer.
*/
if (c0_compare_int_pending()) {
- write_c0_compare(read_c0_count());
+ c0_timer_ack();
irq_disable_hazard();
if (c0_compare_int_pending())
return 0;
@@ -208,7 +208,7 @@ static int c0_compare_int_usable(void)
if (!c0_compare_int_pending())
return 0;
- write_c0_compare(read_c0_count());
+ c0_timer_ack();
irq_disable_hazard();
if (c0_compare_int_pending())
return 0;
