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authorPrasad J Pandit <pjp@fedoraproject.org>2016-10-24 16:26:54 +0100
committerPeter Maydell <peter.maydell@linaro.org>2016-10-24 16:26:54 +0100
commit6be8f5e2626e102433e569d9cece2120baf0c879 (patch)
tree2a876f7388e2e8181bd06749f369a8f312f4bd1e /hw
parente78f12221447af1af47a8ebbdabd35ff37e6d1dd (diff)
downloadqemu-6be8f5e2626e102433e569d9cece2120baf0c879.tar.gz
timer: a9gtimer: remove loop to auto-increment comparator
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 <liqiang6-s@360.cn> Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org> Message-id: 1476733226-11635-1-git-send-email-ppandit@redhat.com Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Diffstat (limited to 'hw')
-rw-r--r--hw/timer/a9gtimer.c14
1 files changed, 7 insertions, 7 deletions
diff --git a/hw/timer/a9gtimer.c b/hw/timer/a9gtimer.c
index 772f85f5fd..ce1dc63911 100644
--- a/hw/timer/a9gtimer.c
+++ b/hw/timer/a9gtimer.c
@@ -82,15 +82,15 @@ 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) {
+ uint64_t inc =
+ QEMU_ALIGN_UP(update.new - gtb->compare, 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;