From 7df7d8dd4b2d67f336995daeee381a07787d9db3 Mon Sep 17 00:00:00 2001 From: Ruihai Zhou Date: Fri, 10 Jun 2022 15:27:33 +0800 Subject: [PATCH] mb/google/corsola: Fix PS8640 power-on T6 sequence The T6 of PS8640 power on sequence should be larger than 0ms, but it's -0.062ms now. Add 100us delay between VRF12 and VCN33. The PS8640 power-on sequence is described in the "PS8640_DS_V1.4_20200210.docx". BUG=b:235448279 BRANCH=None TEST=The sequence T6 is larger than 0ms when power on. Signed-off-by: Ruihai Zhou Change-Id: I0b8a37d6119dc027a9d1c0a62c087b0a7ef14cac Reviewed-on: https://review.coreboot.org/c/coreboot/+/65084 Tested-by: build bot (Jenkins) Reviewed-by: zanxi chen Reviewed-by: Bo-Chen Chen Reviewed-by: Yidi Lin Reviewed-by: Yu-Ping Wu --- src/mainboard/google/corsola/display.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/src/mainboard/google/corsola/display.c b/src/mainboard/google/corsola/display.c index 2af9fe09b2..5a88cad7b9 100644 --- a/src/mainboard/google/corsola/display.c +++ b/src/mainboard/google/corsola/display.c @@ -22,6 +22,7 @@ static void bridge_ps8640_power_on(void) /* * PS8640 power-on sequence is described in chapter 14, PS8640_DS_V1.4_20200210.docx * - set VDD12 to be 1.2V + * - delay 100us * - set VDD33 to be 3.3V * - pull hign PD# * - pull down RST# @@ -35,6 +36,7 @@ static void bridge_ps8640_power_on(void) /* Set VRF12 to 1.2V and VCN33 to 3.3V */ mainboard_set_regulator_vol(MTK_REGULATOR_VRF12, 1200000); + udelay(100); mainboard_set_regulator_vol(MTK_REGULATOR_VCN33, 3300000); udelay(200);