google/snow: Add "wakeup" module for suspend/resume.

The "wakeup" procedure will be shared by bootblock and romstage for different
types of resume processes.

Note, this commit does not include changes in romstage/bootblock to enable
suspend/resume feature. Simply adding functions to handle suspend/resume.

Verified by successfully building and booting Google/Snow firmware image.

Change-Id: I17a256afb99f2f8b5e0eac3393cdf6959b239341
Signed-off-by: Hung-Te Lin <hungte@chromium.org>
Reviewed-on: http://review.coreboot.org/3129
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>

src/cpu/samsung/exynos5250/Makefile.inc

@@ -3,7 +3,7 @@
 # image outside of CBFS
 #INTERMEDIATE += exynos5250_add_bl1
 
-bootblock-y += pinmux.c mct.c
+bootblock-y += pinmux.c mct.c power.c
 # Clock is required for UART
 bootblock-$(CONFIG_EARLY_CONSOLE) += clock_init.c
 bootblock-$(CONFIG_EARLY_CONSOLE) += clock.c

src/mainboard/google/snow/Makefile.inc

@@ -17,9 +17,12 @@
 ## Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
 ##
 
+bootblock-y += wakeup.c
+
 romstage-y += mainboard.c
 romstage-y += memory.c
 romstage-y += romstage.c
+romstage-y += wakeup.c
 
 # ramstage-y += ec.c
 ramstage-y += ramstage.c

src/mainboard/google/snow/mainboard.h

@@ -35,4 +35,15 @@ enum snow_board_config {
 
 int board_get_config(void);
 
+enum {
+	BOARD_IS_NOT_WAKEUP,  // A normal boot (not suspend/resume).
+	BOARD_WAKEUP_DIRECT,  // A wake up event that can be resumed any time.
+	BOARD_WAKEUP_NEED_CLOCK_RESET,  // A wake up event that must be resumed
+					// only after clock and memory
+					// controllers are re-initialized.
+};
+
+int board_get_wakeup_state(void);
+void board_wakeup(void);
+
 #endif	/* MAINBOARD_H */

src/mainboard/google/snow/romstage.c

@@ -46,19 +46,6 @@
 #define PMIC_BUS	0
 #define MMC0_GPIO_PIN	(58)
 
-#if 0
-static int board_wakeup_permitted(void)
-{
-	const int gpio = GPIO_Y10;
-	int is_bad_wake;
-
-	/* We're a bad wakeup if the gpio was defined and was high */
-	is_bad_wake = ((gpio != -1) && gpio_get_value(gpio));
-
-	return !is_bad_wake;
-}
-#endif
-
 static int setup_pmic(void)
 {
 	int error = 0;

src/mainboard/google/snow/wakeup.c

@@ -0,0 +1,62 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2013 Google, Inc.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <arch/gpio.h>
+#include <arch/hlt.h>
+#include <console/console.h>
+#include <cpu/samsung/exynos5250/gpio.h>
+#include <cpu/samsung/exynos5250/power.h>
+#include <cpu/samsung/exynos5-common/exynos5-common.h>
+
+#include "mainboard.h"
+
+static int wakeup_need_reset(void)
+{
+	/* The "wake up" event is not reliable (known as "bad wakeup") and needs
+	 * reset if GPIO value is high. */
+	return gpio_get_value(GPIO_Y10);
+}
+
+void board_wakeup(void)
+{
+	if (wakeup_need_reset())
+		power_reset();
+
+	power_init();  /* Ensure ps_hold_setup() for early wakeup. */
+	power_exit_wakeup();
+	/* Should never return. */
+	die("Failed to wake up.\n");
+}
+
+int board_get_wakeup_state()
+{
+	uint32_t status = power_read_reset_status();
+
+	/* DIDLE/LPA can be resumed without clock reset (ex, bootblock),
+	 * and SLEEP requires resetting clock (should be done in ROM stage).
+	 */
+
+	if (status == S5P_CHECK_DIDLE || status == S5P_CHECK_LPA)
+		return BOARD_WAKEUP_DIRECT;
+
+	if (status == S5P_CHECK_SLEEP)
+		return BOARD_WAKEUP_NEED_CLOCK_RESET;
+
+	return BOARD_IS_NOT_WAKEUP;
+}