qemu-devel.nongnu.org archive mirror
 help / color / mirror / Atom feed
From: Peter Maydell <peter.maydell@linaro.org>
To: qemu-devel@nongnu.org
Subject: [Qemu-devel] [PULL 24/32] timer: a9gtimer: remove loop to auto-increment comparator
Date: Mon, 24 Oct 2016 18:25:20 +0100	[thread overview]
Message-ID: <1477329928-26414-25-git-send-email-peter.maydell@linaro.org> (raw)
In-Reply-To: <1477329928-26414-1-git-send-email-peter.maydell@linaro.org>

From: Prasad J Pandit <pjp@fedoraproject.org>

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>
---
 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

  parent reply	other threads:[~2016-10-24 17:25 UTC|newest]

Thread overview: 35+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-10-24 17:24 [Qemu-devel] [PULL 00/32] target-arm queue Peter Maydell
2016-10-24 17:24 ` [Qemu-devel] [PULL 01/32] migration: Remove static allocation of xzblre cache buffer Peter Maydell
2016-10-24 17:24 ` [Qemu-devel] [PULL 02/32] exec.c: Remove static allocation of sub_section of sub_page Peter Maydell
2016-10-24 17:24 ` [Qemu-devel] [PULL 03/32] translate-all.c: Compute L1 page table properties at runtime Peter Maydell
2016-10-24 17:25 ` [Qemu-devel] [PULL 04/32] cpu: Support a target CPU having a variable page size Peter Maydell
2016-10-24 17:25 ` [Qemu-devel] [PULL 05/32] migration/savevm.c: migrate non-default " Peter Maydell
2016-10-24 17:25 ` [Qemu-devel] [PULL 06/32] target-arm: Make page size a runtime setting Peter Maydell
2016-10-24 17:25 ` [Qemu-devel] [PULL 07/32] hw/arm/virt: Set minimum_page_bits to 12 Peter Maydell
2016-10-24 17:25 ` [Qemu-devel] [PULL 08/32] hw/ptimer: Add "wraparound after one period" policy Peter Maydell
2016-10-24 17:25 ` [Qemu-devel] [PULL 09/32] tests: ptimer: Add tests for " Peter Maydell
2016-10-24 17:25 ` [Qemu-devel] [PULL 10/32] hw/ptimer: Add "continuous trigger" policy Peter Maydell
2016-10-24 17:25 ` [Qemu-devel] [PULL 11/32] tests: ptimer: Add tests for " Peter Maydell
2016-10-24 17:25 ` [Qemu-devel] [PULL 12/32] hw/ptimer: Add "no immediate " Peter Maydell
2016-10-24 17:25 ` [Qemu-devel] [PULL 13/32] tests: ptimer: Add tests for " Peter Maydell
2016-10-24 17:25 ` [Qemu-devel] [PULL 14/32] hw/ptimer: Add "no immediate reload" policy Peter Maydell
2016-10-24 17:25 ` [Qemu-devel] [PULL 15/32] tests: ptimer: Add tests for " Peter Maydell
2016-10-24 17:25 ` [Qemu-devel] [PULL 16/32] hw/ptimer: Add "no counter round down" policy Peter Maydell
2016-10-24 17:25 ` [Qemu-devel] [PULL 17/32] tests: ptimer: Add tests for " Peter Maydell
2016-10-24 17:25 ` [Qemu-devel] [PULL 18/32] tests: ptimer: Change the copyright comment Peter Maydell
2016-10-24 17:25 ` [Qemu-devel] [PULL 19/32] tests: ptimer: Replace 10000 with 1 Peter Maydell
2016-10-24 17:25 ` [Qemu-devel] [PULL 20/32] arm_mptimer: Convert to use ptimer Peter Maydell
2016-10-24 17:25 ` [Qemu-devel] [PULL 21/32] tests: Add tests for the ARM MPTimer Peter Maydell
2016-10-24 17:25 ` [Qemu-devel] [PULL 22/32] ACPI: Add IORT Structure definition Peter Maydell
2016-10-24 17:25 ` [Qemu-devel] [PULL 23/32] ARM: Virt: ACPI: Build an IORT table with RC and ITS nodes Peter Maydell
2016-10-24 17:25 ` Peter Maydell [this message]
2016-10-24 17:25 ` [Qemu-devel] [PULL 25/32] i2c: Fix SMBus read transactions to avoid double events Peter Maydell
2016-10-24 17:25 ` [Qemu-devel] [PULL 26/32] timer: stm32f2xx_timer: add check for prescaler value Peter Maydell
2016-10-24 17:25 ` [Qemu-devel] [PULL 27/32] hw/arm: QOM'ify musicpal.c Peter Maydell
2016-10-24 17:25 ` [Qemu-devel] [PULL 28/32] hw/arm: QOM'ify pxa2xx_gpio.c Peter Maydell
2016-10-24 17:25 ` [Qemu-devel] [PULL 29/32] hw/arm: QOM'ify strongarm.c Peter Maydell
2016-10-24 17:25 ` [Qemu-devel] [PULL 30/32] hw/display: QOM'ify pl110.c Peter Maydell
2016-10-24 17:25 ` [Qemu-devel] [PULL 31/32] target-arm: Implement new HLT trap for semihosting Peter Maydell
2016-10-24 17:25 ` [Qemu-devel] [PULL 32/32] i2c: Add asserts for second smbus i2c_start_transfer() Peter Maydell
2016-10-24 19:11 ` [Qemu-devel] [PULL 00/32] target-arm queue no-reply
2016-10-25  9:17 ` Peter Maydell

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1477329928-26414-25-git-send-email-peter.maydell@linaro.org \
    --to=peter.maydell@linaro.org \
    --cc=qemu-devel@nongnu.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).