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[Qemu-arm] [PATCH v4] timer: a9gtimer: remove loop to auto-increment com
From: |
P J P |
Subject: |
[Qemu-arm] [PATCH v4] timer: a9gtimer: remove loop to auto-increment comparator |
Date: |
Sat, 8 Oct 2016 10:34:18 +0530 |
From: Prasad J Pandit <address@hidden>
ARM A9MP processor has a peripheral timer with an auto-increment
register, which holds an increment step value. A user could set
this value to zero. When auto-increment control bit is enabled,
it leads to an infinite loop in 'a9_gtimer_update' while
updating comparator value. Remove this loop incrementing the
comparator value.
Reported-by: Li Qiang <address@hidden>
Signed-off-by: Prasad J Pandit <address@hidden>
---
hw/timer/a9gtimer.c | 15 ++++++++-------
1 file changed, 8 insertions(+), 7 deletions(-)
Update per
-> https://lists.gnu.org/archive/html/qemu-devel/2016-10/msg01393.html
diff --git a/hw/timer/a9gtimer.c b/hw/timer/a9gtimer.c
index 772f85f..02092dd 100644
--- a/hw/timer/a9gtimer.c
+++ b/hw/timer/a9gtimer.c
@@ -73,6 +73,7 @@ static void a9_gtimer_update(A9GTimerState *s, bool sync)
A9GTimerUpdate update = a9_gtimer_get_update(s);
int i;
+ uint64_t inc;
int64_t next_cdiff = 0;
for (i = 0; i < s->num_cpu; ++i) {
@@ -82,15 +83,15 @@ static void a9_gtimer_update(A9GTimerState *s, bool sync)
if ((s->control & R_CONTROL_TIMER_ENABLE) &&
(gtb->control & R_CONTROL_COMP_ENABLE)) {
/* R2p0+, where the compare function is >= */
- while (gtb->compare < update.new) {
+ if (gtb->compare < update.new) {
DB_PRINT("Compare event happened for CPU %d\n", i);
gtb->status = 1;
- if (gtb->control & R_CONTROL_AUTO_INCREMENT) {
- DB_PRINT("Auto incrementing timer compare by %" PRId32
"\n",
- gtb->inc);
- gtb->compare += gtb->inc;
- } else {
- break;
+ if (gtb->control & R_CONTROL_AUTO_INCREMENT && gtb->inc) {
+ inc = update.new - gtb->compare - 1;
+ inc = QEMU_ALIGN_DOWN(inc, gtb->inc);
+ DB_PRINT("Auto incrementing timer compare by %"
+ PRId64 "\n", inc);
+ gtb->compare += inc;
}
}
cdiff = (int64_t)gtb->compare - (int64_t)update.new + 1;
--
2.5.5
- [Qemu-arm] [PATCH v4] timer: a9gtimer: remove loop to auto-increment comparator,
P J P <=