Google/Snow: Enable suspend/resume.

Add the suspend/resume feature into bootblock and romstage.

Note, resuming with X and touchpad driver may be still unstable.

Verified by building and booting successfully on Google/Snow, and then executing
the "suspend_stress_test" in text mode ("stop ui; suspend_stress_test") in
Chromium OS, passed at least 20 iterations.

Change-Id: I65681c42eeef2736e55bb906595f42a5b1dfdf11
Signed-off-by: Hung-Te Lin <hungte@chromium.org>
Reviewed-on: http://review.coreboot.org/3102
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>

src/mainboard/google/snow/bootblock.c

@@ -25,16 +25,24 @@
 #include <console/console.h>
 #include <cpu/samsung/exynos5250/periph.h>
 #include <cpu/samsung/exynos5250/pinmux.h>
+#include "mainboard.h"
 
 void bootblock_mainboard_init(void);
 void bootblock_mainboard_init(void)
 {
-	/* kick off the microsecond timer. We want to do this as early
-	 * as we can.
+	switch (snow_get_wakeup_state()) {
+		case SNOW_WAKEUP_DIRECT:
+			snow_wakeup();
+			break;
+
+		case SNOW_IS_NOT_WAKEUP:
+			/* kick off the microsecond timer.
+			 * We want to do this as early as we can.
 			 */
 			timer_start();
-
 			exynos_pinmux_config(PERIPH_ID_SPI1, PINMUX_FLAG_NONE);
+			break;
+	}
 #if CONFIG_EARLY_CONSOLE
 	exynos_pinmux_config(PERIPH_ID_UART3, PINMUX_FLAG_NONE);
 	console_init();

src/mainboard/google/snow/romstage.c

@@ -170,15 +170,22 @@ void main(void)
 {
 	struct mem_timings *mem;
 	void *entry;
+	int is_resume = (snow_get_wakeup_state() != SNOW_IS_NOT_WAKEUP);
 
 	/* Clock must be initialized before console_init, otherwise you may need
 	 * to re-initialize serial console drivers again. */
 	mem = snow_setup_clock();
 
+	if (!is_resume) {
 		console_init();
 		snow_setup_power();
+	}
 
-	snow_setup_memory(mem, 0);
+	snow_setup_memory(mem, is_resume);
+
+	if (is_resume) {
+		snow_wakeup();
+	}
 
 	snow_setup_storage();
 	snow_setup_gpio();