diff options
| author | Scott Collyer <scollyer@google.com> | 2019-01-10 21:46:26 -0800 |
|---|---|---|
| committer | chrome-bot <chrome-bot@chromium.org> | 2019-02-04 22:49:19 -0800 |
| commit | ce8939ec86a348c25af32a0e07aadd6054f510a8 (patch) | |
| tree | 9bebeacee3638acda9e33e750991151cbf641478 /power/cometlake.c | |
| parent | fe59e6140d7ff8ee90359d3144bffb6fbcf4e053 (diff) | |
| download | chrome-ec-ce8939ec86a348c25af32a0e07aadd6054f510a8.tar.gz | |
cometlake: Guard passing RSMRST_L to PCH by PP5000_A rail
RSMRST_L gets passed along to the AP by EC when it changes state. For
low to high transitions the EC needs to ensure that the PP5000_A rail
is up prior to passing the RSMRST_L transition to the AP.
This CL adds a check to prevent calling
common_intel_x86_handle_rsmrst() when RSMRST_L is high if the PP5000_A
rail is not up. Since PP5000_PG signal will float high when the
regulator is not powered at all, both the enable and power good
signals are used to verify that PP5000_A rail is powered.
BRANCH=none
BUG=b:122631914
TEST=Verified on scope that RSMRST_L to PCH rising edge happens after
PP5000_A rail rising.
Change-Id: Icfd4dabbdfaf6ae76b3cdcbc6f75a5188a21ff51
Signed-off-by: Scott Collyer <scollyer@google.com>
Reviewed-on: https://chromium-review.googlesource.com/1406497
Commit-Ready: Scott Collyer <scollyer@chromium.org>
Tested-by: Scott Collyer <scollyer@chromium.org>
Reviewed-by: Furquan Shaikh <furquan@chromium.org>
Diffstat (limited to 'power/cometlake.c')
| -rw-r--r-- | power/cometlake.c | 16 |
1 files changed, 15 insertions, 1 deletions
diff --git a/power/cometlake.c b/power/cometlake.c index 27b78efa32..bf27b50dab 100644 --- a/power/cometlake.c +++ b/power/cometlake.c @@ -99,7 +99,21 @@ enum power_state power_handle_state(enum power_state state) int all_sys_pwrgd_in; int all_sys_pwrgd_out; - common_intel_x86_handle_rsmrst(state); + /* + * Check if RSMRST_L signal state has changed and if so, pass the new + * value along to the PCH. However, if the new transition of RSMRST_L + * from the Sielgo is from low to high, then gate this transition to the + * AP by the PP5000_A rail. If the new transition is from high to low, + * then pass that through regardless of the PP5000_A value. + * + * The PP5000_A power good signal will float high if the + * regulator is not powered, so checking both that the EN and the PG + * signals are high. + */ + if ((gpio_get_level(GPIO_PP5000_A_PG_OD) && + gpio_get_level(GPIO_EN_PP5000_A)) || + gpio_get_level(GPIO_PCH_RSMRST_L)) + common_intel_x86_handle_rsmrst(state); switch (state) { |