diff options
| author | Daisuke Nojiri <dnojiri@chromium.org> | 2021-10-11 12:50:25 -0700 |
|---|---|---|
| committer | Chromeos LUCI <chromeos-scoped@luci-project-accounts.iam.gserviceaccount.com> | 2022-03-28 18:17:37 +0000 |
| commit | 768322d728e8e9228b8ce46dfbf0c8954b8650c4 (patch) | |
| tree | f1884a61305a8957955756ec35172ffaf51028de | |
| parent | 5822c27c9775e21410e98ab72c64eb4c1b198e84 (diff) | |
| download | chrome-ec-768322d728e8e9228b8ce46dfbf0c8954b8650c4.tar.gz | |
mec1322/timer: Unroll udelay
This patch flattens udelay by unrolling __hw_clock_source_read.
This increases the chance that we record LR of the instruction
near which an infinite loop happened.
BUG=b:218982018,b:200593658
BRANCH=
TEST=buildall
Change-Id: I8127e9a3308c161fd064e78048d82972bb57e464
Signed-off-by: Daisuke Nojiri <dnojiri@chromium.org>
(cherry picked from commit f0a9a2701fee604ec721b6a23173cec12cd8f4f0)
Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/3508423
| -rw-r--r-- | chip/mec1322/hwtimer.c | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/chip/mec1322/hwtimer.c b/chip/mec1322/hwtimer.c index be9ffac1ea..221633d3f4 100644 --- a/chip/mec1322/hwtimer.c +++ b/chip/mec1322/hwtimer.c @@ -107,3 +107,14 @@ int __hw_clock_source_init(uint32_t start_t) return MEC1322_IRQ_TIMER32_1; } + +/* + * Unrolled udelay. It preserves LR, which points to the root cause of WD crash. + */ +__override void udelay(unsigned us) +{ + unsigned t0 = 0xffffffff - MEC1322_TMR32_CNT(0); + + while (0xffffffff - MEC1322_TMR32_CNT(0) - t0 <= us) + ; +} |