hatch: Fix FPMCU pwr/rst gpio handling

1. No gpio control in bootblock
2. Disable power and assert reset in ramstage gpio
3. Power on and then deassert reset at the end of ramstage gpio
4. Disable power and assert reset when entering S5

On "reboot", the amount of time the power is disabled for is
equivalent to the amount of time between triggering #4 and wrapping
around to #3, which is about 400ms on Kohaku.

Since #2 forces power off for FPMCU, S3 resume will still
not work properly.

Additionally, we must ensure that GPP_A12 is reconfigured as an output
before going to any sleep state, since user space could have configured
it to use its native3 function.
See https://review.coreboot.org/c/coreboot/+/32111 for more detail.

The control signals have been validated on a Kohaku in
the following scenarios:
1. Cold startup
2. Issuing a "reboot" command
3. Issuing a "halt -p" and powering back on within 10 seconds
4. Issuing a "halt -p" and powering back on after 10 seconds
5. Entering and leaving S3 (does not work properly)
6. Entering and leaving S0iX

BRANCH=hatch
BUG=b/142751685
TEST=Verify all signals as mentioned above
TEST=reboot
     flash_fp_mcu /opt/google/biod/fw/dartmonkey_v2.0.2417-af88cc91a.bin
TEST=halt -p
     # power back on within 10 seconds
     flash_fp_mcu /opt/google/biod/fw/dartmonkey_v2.0.2417-af88cc91a.bin
TEST=halt -p
     # power back on after 10 seconds
     flash_fp_mcu /opt/google/biod/fw/dartmonkey_v2.0.2417-af88cc91a.bin

Change-Id: I2e3ff42715611d519677a4256bdd172ec98687f9
Signed-off-by: Craig Hesling <hesling@chromium.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/37459
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Furquan Shaikh <furquan@google.com>

2 files changed, 12 insertions, 6 deletions

diff --git a/src/mainboard/google/hatch/variants/baseboard/gpio.c b/src/mainboard/google/hatch/variants/baseboard/gpio.c
index 598600bda3..94cb2e53a2 100644
--- a/src/mainboard/google/hatch/variants/baseboard/gpio.c
+++ b/src/mainboard/google/hatch/variants/baseboard/gpio.c
@@ -38,7 +38,7 @@ static const struct pad_config gpio_table[] = {
 	/* A11 : PCH_SPI_FPMCU_CS_L */
 	PAD_CFG_NF(GPP_A11, NONE, DEEP, NF2),
 	/* A12 : FPMCU_RST_ODL */
-	PAD_CFG_GPO(GPP_A12, 1, DEEP),
+	PAD_CFG_GPO(GPP_A12, 0, DEEP),
 	/* A13 : SUSWARN_L */
 	PAD_CFG_NF(GPP_A13, NONE, DEEP, NF1),
 	/* A14 : ESPI_RST_L */
@@ -133,7 +133,7 @@ static const struct pad_config gpio_table[] = {
 	/* C10 : GPP_10 ==> GPP_C10_TP */
 	PAD_NC(GPP_C10, NONE),
 	/* C11 : GPP_11 ==> EN_FP_RAILS */
-	PAD_CFG_GPO(GPP_C11, 1, DEEP),
+	PAD_CFG_GPO(GPP_C11, 0, DEEP),
 	/* C12 : GPP_C12 ==> NC */
 	PAD_NC(GPP_C12, NONE),
 	/* C13 : EC_PCH_INT_L */
@@ -398,8 +398,10 @@ const struct pad_config *base_gpio_table(size_t *num)
 }
 
 /*
- * Default GPIO settings before entering sleep. Configure A12: FPMCU_RST_ODL
- * as GPO before entering sleep.
+ * Default GPIO settings before entering non-S5 sleep states.
+ * Configure A12: FPMCU_RST_ODL as GPO before entering sleep.
+ * This guarantees that A12's native3 function is disabled.
+ * See https://review.coreboot.org/c/coreboot/+/32111 .
  */
 static const struct pad_config default_sleep_gpio_table[] = {
 	PAD_CFG_GPO(GPP_A12, 1, DEEP), /* FPMCU_RST_ODL */
@@ -408,10 +410,11 @@ static const struct pad_config default_sleep_gpio_table[] = {
 /*
  * GPIO settings before entering S5, which are same as
  * default_sleep_gpio_table but also,
- * turn off EN_PP3300_WWAN.
+ * turn off EN_PP3300_WWAN and FPMCU.
  */
 static const struct pad_config s5_sleep_gpio_table[] = {
-	PAD_CFG_GPO(GPP_A12, 1, DEEP), /* FPMCU_RST_ODL */
+	PAD_CFG_GPO(GPP_A12, 0, DEEP), /* FPMCU_RST_ODL */
+	PAD_CFG_GPO(GPP_C11, 0, DEEP), /* PCH_FP_PWR_EN */
 	PAD_CFG_GPO(GPP_A18, 0, DEEP), /* EN_PP3300_WWAN */
 };
 
diff --git a/src/mainboard/google/hatch/variants/baseboard/include/baseboard/variants.h b/src/mainboard/google/hatch/variants/baseboard/include/baseboard/variants.h
index 920e428484..1542d9bc54 100644
--- a/src/mainboard/google/hatch/variants/baseboard/include/baseboard/variants.h
+++ b/src/mainboard/google/hatch/variants/baseboard/include/baseboard/variants.h
@@ -50,4 +50,7 @@ uint32_t get_board_sku(void);
 /* Modify devictree settings during ramstage. */
 void variant_devtree_update(void);
 
+/* Perform variant specific initialization early on in ramstage. */
+void variant_ramstage_init(void);
+
 #endif /* BASEBOARD_VARIANTS_H */