rambi: Add low power idle to rambi

Added low power idle functionality to rambi but left it off by default.
To turn it on, define CONFIG_LOW_POWER_IDLE in rambi's board.h file.

BRANCH=none
BUG=chrome-os-partner:23947
TEST=Verified that the EC does not go into deep sleep when in S0, and that
it does go into deep sleep in S3, S5, and G3. Tested to make sure that
flashec works when the EC is in low speed deep sleep. Also verified
that the EC console times out after the timeout period and that it wakes
up on the next command. Did not measure power usage.

Change-Id: I0ab1a2dc7ca7ae4577fe5d0894c1bf82205dfea6
Signed-off-by: Alec Berg <alecaberg@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/176159
Reviewed-by: Todd Broch <tbroch@chromium.org>

3 files changed, 31 insertions, 5 deletions

diff --git a/board/rambi/board.c b/board/rambi/board.c
index 845797139b..d20229ec5c 100644
--- a/board/rambi/board.c
+++ b/board/rambi/board.c
@@ -14,6 +14,7 @@
 #include "gpio.h"
 #include "host_command.h"
 #include "i2c.h"
+#include "jtag.h"
 #include "keyboard_scan.h"
 #include "lid_switch.h"
 #include "peci.h"
@@ -26,20 +27,23 @@
 #include "temp_sensor_chip.h"
 #include "thermal.h"
 #include "timer.h"
+#include "uart.h"
 #include "util.h"
 
 /* GPIO signal list.  Must match order from enum gpio_signal. */
 const struct gpio_info gpio_list[] = {
 	/* Inputs with interrupt handlers are first for efficiency */
-	{"POWER_BUTTON_L",       LM4_GPIO_A, (1<<2), GPIO_INT_BOTH,
+	{"POWER_BUTTON_L",       LM4_GPIO_A, (1<<2), GPIO_INT_BOTH_DSLEEP,
 	 power_button_interrupt},
-	{"LID_OPEN",             LM4_GPIO_A, (1<<3), GPIO_INT_BOTH,
+	{"LID_OPEN",             LM4_GPIO_A, (1<<3), GPIO_INT_BOTH_DSLEEP,
 	 lid_interrupt},
-	{"AC_PRESENT",           LM4_GPIO_H, (1<<3), GPIO_INT_BOTH,
+	{"AC_PRESENT",           LM4_GPIO_H, (1<<3), GPIO_INT_BOTH_DSLEEP,
 	 extpower_interrupt},
-	{"PCH_SLP_S3_L",         LM4_GPIO_G, (1<<7), GPIO_INT_BOTH|GPIO_PULL_UP,
+	{"PCH_SLP_S3_L",         LM4_GPIO_G, (1<<7), GPIO_INT_BOTH_DSLEEP |
+							GPIO_PULL_UP,
 	 x86_interrupt},
-	{"PCH_SLP_S4_L",         LM4_GPIO_H, (1<<1), GPIO_INT_BOTH|GPIO_PULL_UP,
+	{"PCH_SLP_S4_L",         LM4_GPIO_H, (1<<1), GPIO_INT_BOTH_DSLEEP |
+							GPIO_PULL_UP,
 	 x86_interrupt},
 	{"PP1050_PGOOD",         LM4_GPIO_H, (1<<4), GPIO_INT_BOTH,
 	 x86_interrupt},
@@ -53,6 +57,11 @@ const struct gpio_info gpio_list[] = {
 	 x86_interrupt},
 	{"WP_L",                 LM4_GPIO_A, (1<<4), GPIO_INT_BOTH,
 	 switch_interrupt},
+	{"JTAG_TCK",             LM4_GPIO_C, (1<<0), GPIO_DEFAULT,
+	 jtag_interrupt},
+	{"UART0_RX",             LM4_GPIO_A, (1<<0), GPIO_INT_BOTH_DSLEEP |
+							GPIO_PULL_UP,
+	 uart_deepsleep_interrupt},
 
 	/* Other inputs */
 	{"BOARD_VERSION1",       LM4_GPIO_Q, (1<<5), GPIO_INPUT, NULL},
diff --git a/board/rambi/board.h b/board/rambi/board.h
index 8412a5535e..34ed193823 100644
--- a/board/rambi/board.h
+++ b/board/rambi/board.h
@@ -71,6 +71,8 @@ enum gpio_signal {
 	GPIO_S5_PGOOD,             /* Power good on S5 supplies */
 	GPIO_VCORE_PGOOD,          /* Power good on core VR */
 	GPIO_WP_L,                 /* Write protect input */
+	GPIO_JTAG_TCK,             /* JTAG clock input */
+	GPIO_UART0_RX,             /* UART0 RX input */
 
 	/* Other inputs */
 	GPIO_BOARD_VERSION1,       /* Board version stuffing resistor 1 */
diff --git a/power/baytrail.c b/power/baytrail.c
index 9ca1633a2f..3f7f217f24 100644
--- a/power/baytrail.c
+++ b/power/baytrail.c
@@ -113,6 +113,9 @@ enum x86_state x86_chipset_init(void)
 	 */
 	if (system_jumped_to_this_image()) {
 		if ((x86_get_signals() & IN_ALL_S0) == IN_ALL_S0) {
+			/* Disable idle task deep sleep when in S0. */
+			disable_sleep(SLEEP_MASK_AP_RUN);
+
 			CPRINTF("[%T x86 already in S0]\n");
 			return X86_S0;
 		} else {
@@ -266,6 +269,12 @@ enum x86_state x86_handle_state(enum x86_state state)
 		/* Call hooks now that rails are up */
 		hook_notify(HOOK_CHIPSET_RESUME);
 
+		/*
+		 * Disable idle task deep sleep. This means that the low
+		 * power idle task will not go into deep sleep while in S0.
+		 */
+		disable_sleep(SLEEP_MASK_AP_RUN);
+
 		/* Wait 100ms after all voltages good */
 		msleep(100);
 
@@ -298,6 +307,12 @@ enum x86_state x86_handle_state(enum x86_state state)
 		wireless_enable(0);
 
 		/*
+		 * Enable idle task deep sleep. Allow the low power idle task
+		 * to go into deep sleep in S3 or lower.
+		 */
+		enable_sleep(SLEEP_MASK_AP_RUN);
+
+		/*
 		 * Deassert prochot since CPU is off and we're about to drop
 		 * +VCCP.
 		 */