[coreboot-gerrit] Change in ...coreboot[master]: mb/google/hatch: Re-configure GPP_A12 as GPO before entering sleep

[Patrick Georgi (Code Review)]

Patrick Georgi has submitted this change and it was merged. ( https://review.coreboot.org/c/coreboot/+/32111 )

Change subject: mb/google/hatch: Re-configure GPP_A12 as GPO before entering sleep
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mb/google/hatch: Re-configure GPP_A12 as GPO before entering sleep

GPP_A12 has a Native3 (SX_EXIT_HOLDOFF#) mode, which allows to delay
resuming to S0. If this pad is not locked and platform was not initially
designed for this functionality, malware could reconfigure this pads
setting under OS (switch to Native3), which would make platform not able
to resume until G3 is applied. To prevent misuse of this pad,
re-configure this pad before entering S3 and S5 to guarantee that the
pad configuration is correct.

BUG=b:128686027

Change-Id: I1e7979baa491acf2c56d223afb4618f0f6429e37
Signed-off-by: Krishna Prasad Bhat 
Reviewed-on: https://review.coreboot.org/c/coreboot/+/32111
Tested-by: build bot (Jenkins) 
Reviewed-by: Furquan Shaikh 
---
M src/mainboard/google/hatch/variants/baseboard/gpio.c
1 file changed, 6 insertions(+), 1 deletion(-)

Approvals:
  build bot (Jenkins): Verified
  Furquan Shaikh: Looks good to me, approved

diff --git a/src/mainboard/google/hatch/variants/baseboard/gpio.c b/src/mainboard/google/hatch/variants/baseboard/gpio.c
index b974e49..8529d5916 100644
--- a/src/mainboard/google/hatch/variants/baseboard/gpio.c
+++ b/src/mainboard/google/hatch/variants/baseboard/gpio.c
@@ -411,8 +411,12 @@
    return gpio_table;
 }

-/* Default GPIO settings before entering sleep. */
+/*
+ * Default GPIO settings before entering sleep. Configure A12: FPMCU_RST_ODL
+ * as GPO before entering sleep.
+ */
 static const struct pad_config default_sleep_gpio_table[] = {
+	PAD_CFG_GPO(GPP_A12, 1, DEEP), /* FPMCU_RST_ODL */
 };

/*
@@ -421,6 +425,7 @@
  * turn off EN_PP3300_WWAN.
  */
 static const struct pad_config s5_sleep_gpio_table[] = {
+	PAD_CFG_GPO(GPP_A12, 1, DEEP), /* FPMCU_RST_ODL */
    PAD_CFG_GPO(GPP_A18, 0, DEEP), /* EN_PP3300_WWAN */
 };