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| author | Jett Rink <jettrink@chromium.org> | 2019-09-06 11:33:48 -0600 |
|---|---|---|
| committer | Commit Bot <commit-bot@chromium.org> | 2019-09-12 05:04:17 +0000 |
| commit | 031c5d2d62dd891622ded885756c03021e934ef2 (patch) | |
| tree | bddaeeeb33e89134f538795d050d5874649ef90f /chip/npcx/watchdog.c | |
| parent | 8d9ddb34ed3465e5172c6d950a155c83dd6d5aa9 (diff) | |
| download | chrome-ec-031c5d2d62dd891622ded885756c03021e934ef2.tar.gz | |
npcx: ensure we don't unlock watchdog too soon
We cannot unlock the watchdog timer with 3 watch dog ticks of touching
it per the datasheet. This is actually around 100ms so we should protect
against this.
BRANCH=none
BUG=b:140207603
TEST=eliminates cold reset issue.
Change-Id: Iaef59dad9f5640d64d5d430aea87bd16c2efd30d
Signed-off-by: Jett Rink <jettrink@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/1790302
Reviewed-by: Scott Collyer <scollyer@chromium.org>
Reviewed-by: Tim Wawrzynczak <twawrzynczak@chromium.org>
Reviewed-by: ML Chao <mlchao@nuvoton.corp-partner.google.com>
Reviewed-by: Furquan Shaikh <furquan@chromium.org>
Tested-by: Furquan Shaikh <furquan@chromium.org>
Commit-Queue: Furquan Shaikh <furquan@chromium.org>
Diffstat (limited to 'chip/npcx/watchdog.c')
| -rw-r--r-- | chip/npcx/watchdog.c | 28 |
1 files changed, 25 insertions, 3 deletions
diff --git a/chip/npcx/watchdog.c b/chip/npcx/watchdog.c index 44a980326b..233c875643 100644 --- a/chip/npcx/watchdog.c +++ b/chip/npcx/watchdog.c @@ -58,6 +58,27 @@ static uint8_t watchdog_count(void) return cnt; } +static timestamp_t last_watchdog_touch; +void watchdog_stop_and_unlock(void) +{ + /* + * Ensure we have waited at least 3 watchdog ticks since touching WD + * timer. 3 / (32768 / 1024) HZ = 93.75ms + */ + while (time_since32(last_watchdog_touch) < (100 * MSEC)) + continue; + + NPCX_WDSDM = 0x87; + NPCX_WDSDM = 0x61; + NPCX_WDSDM = 0x63; +} + +static void touch_watchdog_count(void) +{ + NPCX_WDSDM = 0x5C; + last_watchdog_touch = get_time(); +} + void __keep watchdog_check(uint32_t excep_lr, uint32_t excep_sp) { int wd_cnt; @@ -75,7 +96,8 @@ void __keep watchdog_check(uint32_t excep_lr, uint32_t excep_sp) * Touch watchdog to let UART have enough time * to print panic info */ - NPCX_WDSDM = 0x5C; + touch_watchdog_count(); + /* Print panic info */ watchdog_trace(excep_lr, excep_sp); cflush(); @@ -112,7 +134,7 @@ void watchdog_reload(void) #if 1 /* mark this for testing watchdog */ /* Touch watchdog & reset software counter */ - NPCX_WDSDM = 0x5C; + touch_watchdog_count(); #endif /* Enable watchdog interrupt */ @@ -125,7 +147,7 @@ int watchdog_init(void) #if SUPPORT_WDG /* Touch watchdog before init if it is already running */ if (IS_BIT_SET(NPCX_T0CSR, NPCX_T0CSR_WD_RUN)) - NPCX_WDSDM = 0x5C; + touch_watchdog_count(); /* Keep prescaler ratio timer0 clock to 1:1024 */ NPCX_TWCP = 0x0A; |