[S] Change in coreboot[main]: mb/google/rex/var/rex0: Toggle NVMe PWR pin to reset SSD

[Subrata Banik (Code Review)]

Subrata Banik has submitted this change. ( https://review.coreboot.org/c/coreboot/+/71221?usp=email )

Change subject: mb/google/rex/var/rex0: Toggle NVMe PWR pin to reset SSD
......................................................................

mb/google/rex/var/rex0: Toggle NVMe PWR pin to reset SSD

During warm reboot, NVMe is not detected with non-serial image
sometimes while there is no issue with serial image. This change
toggles NVMe PWR pin as soon as in early stage to make NVMe ready
sooner.

BUG=b:260547988
BRANCH=None
TEST= Build rex0 and try warm reboot from OS console. Check if
the platform with Micron SSD boots to OS again without an issue.

Signed-off-by: Wonkyu Kim 
Change-Id: I2f34e3f49e7fc388198ff85c8e119cb3f242a60e
Reviewed-on: https://review.coreboot.org/c/coreboot/+/71221
Tested-by: build bot (Jenkins) 
Reviewed-by: Subrata Banik 
---
M src/mainboard/google/rex/variants/rex0/gpio.c
1 file changed, 8 insertions(+), 3 deletions(-)

Approvals:
  Subrata Banik: Looks good to me, approved
  build bot (Jenkins): Verified

diff --git a/src/mainboard/google/rex/variants/rex0/gpio.c b/src/mainboard/google/rex/variants/rex0/gpio.c
index 6cd24b7..184c4d2 100644
--- a/src/mainboard/google/rex/variants/rex0/gpio.c
+++ b/src/mainboard/google/rex/variants/rex0/gpio.c
@@ -376,6 +376,11 @@

/* Early pad configuration in bootblock */
 static const struct pad_config early_gpio_table[] = {
+	/* GPP_A19 : [] ==> EN_PP3300_SSD */
+	PAD_CFG_GPO(GPP_A19, 0, DEEP),
+	/* GPP_A20 : [] ==> SSD_PERST_L */
+	PAD_CFG_GPO(GPP_A20, 1, DEEP),
+
    /* GPP_B16 : [] ==> SOC_HDMI_HPD_L */
    PAD_CFG_NF(GPP_B16, NONE, DEEP, NF2),
    /* GPP_B17 : [] ==> EN_WWAN_PWR */
@@ -410,14 +415,14 @@
    /* GPP_E13 :  [] ==> MEM_CH_SEL */
    PAD_CFG_GPI(GPP_E13, NONE, DEEP),

-	/* GPP_A20 : [] ==> SSD_PERST_L */
-	PAD_CFG_GPO(GPP_A20, 0, DEEP),
-
    /* GPP_H10 : [] ==> SOC_WP_OD */
    PAD_CFG_GPI_GPIO_DRIVER_LOCK(GPP_H10, NONE, LOCK_CONFIG),
 };

static const struct pad_config romstage_gpio_table[] = {
+	/* GPP_A19 : [] ==> EN_PP3300_SSD */
+	PAD_CFG_GPO(GPP_A19, 1, DEEP),
+
    /* GPP_B11 : [] ==> EN_FP_PWR */
    PAD_CFG_GPO(GPP_B11, 0, DEEP),
    /* A20 : [] ==> SSD_PERST_L */