From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:35235) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1byj0J-0006RT-DI for qemu-devel@nongnu.org; Mon, 24 Oct 2016 13:25:48 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1byj0H-0007Ru-De for qemu-devel@nongnu.org; Mon, 24 Oct 2016 13:25:43 -0400 Received: from orth.archaic.org.uk ([2001:8b0:1d0::2]:47422) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1byj0H-0007QU-62 for qemu-devel@nongnu.org; Mon, 24 Oct 2016 13:25:41 -0400 Received: from pm215 by orth.archaic.org.uk with local (Exim 4.84_2) (envelope-from ) id 1byj0G-0002Q4-8r for qemu-devel@nongnu.org; Mon, 24 Oct 2016 18:25:40 +0100 From: Peter Maydell Date: Mon, 24 Oct 2016 18:25:20 +0100 Message-Id: <1477329928-26414-25-git-send-email-peter.maydell@linaro.org> In-Reply-To: <1477329928-26414-1-git-send-email-peter.maydell@linaro.org> References: <1477329928-26414-1-git-send-email-peter.maydell@linaro.org> Subject: [Qemu-devel] [PULL 24/32] timer: a9gtimer: remove loop to auto-increment comparator List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org From: Prasad J Pandit 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 Signed-off-by: Prasad J Pandit Message-id: 1476733226-11635-1-git-send-email-ppandit@redhat.com Reviewed-by: Peter Maydell Signed-off-by: Peter Maydell --- hw/timer/a9gtimer.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/hw/timer/a9gtimer.c b/hw/timer/a9gtimer.c index 772f85f..ce1dc63 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; -- 2.7.4