glados: implement x86 power cycle on EC reset

On certain glados boards (board id >= 2) there is a
gpio conntected to the LDO_EN pin of the BD99992 pmic.
This is a requirement for pulling power from the x86
side of the system. Add a check at HOOK_INIT time to
check the current system reset flags. If a watchdog,
hard, or soft reboot occurred the LDO_EN is deasserted
to bring down the DSW and primary rails.

BUG=chrome-os-partner:44527
BRANCH=None
TEST='reboot', 'reboot ap-off', host cmd reboot.

Change-Id: I7e971a03c8894e1cbf20aaad67903db2057aad41
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/295116
Reviewed-by: Shawn N <shawnn@chromium.org>

2 files changed, 41 insertions, 2 deletions

diff --git a/board/glados/board.c b/board/glados/board.c
index 6d8d0c1a00..c70b17b36f 100644
--- a/board/glados/board.c
+++ b/board/glados/board.c
@@ -370,3 +370,38 @@ uint32_t board_get_gpio_hibernate_state(uint32_t port, uint32_t pin)
 	/* Other GPIOs should be put in a low-power state */
 	return GPIO_INPUT | GPIO_PULL_UP;
 }
+
+/* Any glados boards post version 2 should have ROP_LDO_EN stuffed. */
+#define BOARD_MIN_ID_LOD_EN 2
+/* Make the pmic re-sequence the power rails under these conditions. */
+#define PMIC_RESET_FLAGS \
+	(RESET_FLAG_WATCHDOG | RESET_FLAG_SOFT | RESET_FLAG_HARD)
+static void board_handle_reboot(void)
+{
+	int flags;
+	const struct gpio_info *g = &gpio_list[GPIO_BATLOW_L_PMIC_LDO_EN];
+
+	if (system_jumped_to_this_image())
+		return;
+
+	if (system_get_board_version() < BOARD_MIN_ID_LOD_EN)
+		return;
+
+	/* Interrogate current reset flags from previous reboot. */
+	flags = system_get_reset_flags();
+
+	if (!(flags & PMIC_RESET_FLAGS))
+		return;
+
+	/* Preserve AP off request. */
+	if (flags & RESET_FLAG_AP_OFF)
+		chip_save_reset_flags(RESET_FLAG_AP_OFF);
+
+	ccprintf("Restarting system with PMIC.\n");
+	/* Flush console */
+	cflush();
+
+	/* Bring down all rails but RTC rail (including EC power). */
+	gpio_set_flags_by_mask(g->port, g->mask, GPIO_OUT_HIGH);
+}
+DECLARE_HOOK(HOOK_INIT, board_handle_reboot, HOOK_PRIO_FIRST);
diff --git a/board/glados/gpio.inc b/board/glados/gpio.inc
index 59d886fe32..22b225ef9f 100644
--- a/board/glados/gpio.inc
+++ b/board/glados/gpio.inc
@@ -95,8 +95,12 @@ GPIO(SYS_RESET_L,           PIN(121), GPIO_ODR_HIGH)
 GPIO(CHARGE_LED_1,        PIN(155), GPIO_OUT_LOW)
 GPIO(CHARGE_LED_2,        PIN(156), GPIO_OUT_LOW)
 
-/* Inhibit the AP from booting until we can supply enough current */
-GPIO(PCH_BATLOW_L,          PIN(55),  GPIO_ODR_HIGH)
+/*
+ * BATLOW_L and ROP_LDO_EN are stuffing options. Set as input to dynamically
+ * handle the stuffing option based on board id. As both signals have external
+ * pulls setting this pin as input won't harm anything.
+ */
+GPIO(BATLOW_L_PMIC_LDO_EN,  PIN(55),  GPIO_INPUT)
 GPIO(ACCEL4_INT,            PIN(157), GPIO_INPUT)
 GPIO(PP1800_DX_AUDIO_EN,    PIN(141), GPIO_OUT_LOW)
 /* NC / stuffing option */