chromeos: Provide common watchdog reboot support

Many ChromeOS devices use a GPIO to reset the system, in order to
guarantee that the TPM cannot be reset without also resetting the CPU.
Often chipset/SoC hardware watchdogs trigger some kind of built-in
CPU reset, bypassing this GPIO and thus leaving the TPM locked. These
ChromeOS devices need to detect that condition in their bootblock and
trigger a second (proper) reboot.

This patch adds some code to generalize this previously
mainboard-specific functionality and uses it on Veyron boards. It also
provides some code to add the proper eventlog entry for a watchdog
reset. Since the second reboot has to happen before firmware
verification and the eventlog is usually only initialized afterwards, we
provide the functionality to place a tombstone in a memlayout-defined
location (which could be SRAM or some MMIO register that is preserved
across reboots).

[pg: Integrates
 'mips: Temporarily work around build error caused by <arch/io.h> mismatch]

BRANCH=veyron
BUG=chrome-os-partner:35705
TEST=Run 'mem w 0xff800000 0x9' on a Jerry, watch how a "Hardware
watchdog reset" event appears in the eventlog after the reboot.

Change-Id: I0a33820b236c9328b2f9b20905b69cb934326f2a
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Original-Commit-Id: fffc484bb89f5129d62739dcb44d08d7f5b30b33
Original-Change-Id: I7ee1d02676e9159794d29e033d71c09fdf4620fd
Original-Signed-off-by: Julius Werner <jwerner@chromium.org>
Original-Reviewed-on: https://chromium-review.googlesource.com/242404
Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Original-Commit-Id: c919c72ddc9d2e1e18858c0bf49c0ce79f2bc506
Original-Change-Id: I509c842d3393bd810e89ebdf0dc745275c120c1d
Original-Signed-off-by: Julius Werner <jwerner@chromium.org>
Original-Reviewed-on: https://chromium-review.googlesource.com/242504
Original-Reviewed-by: David Hendricks <dhendrix@chromium.org>
Reviewed-on: http://review.coreboot.org/9749
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>

2 files changed, 3 insertions, 4 deletions

diff --git a/src/mainboard/google/veyron_mighty/bootblock.c b/src/mainboard/google/veyron_mighty/bootblock.c
index 90ad744980..acf81bc0cb 100644
--- a/src/mainboard/google/veyron_mighty/bootblock.c
+++ b/src/mainboard/google/veyron_mighty/bootblock.c
@@ -58,10 +58,8 @@ void bootblock_mainboard_init(void)
 	udelay(100);/* Must wait for voltage to stabilize,2mV/us */
 	rkclk_configure_cpu();
 
-	if (rkclk_was_watchdog_reset()) {
-		printk(BIOS_INFO, "Last reset was watchdog... rebooting via GPIO!\n");
-		hard_reset();
-	}
+	if (rkclk_was_watchdog_reset())
+		reboot_from_watchdog();
 
 	/* i2c1 for tpm */
 	writel(IOMUX_I2C1, &rk3288_grf->iomux_i2c1);
diff --git a/src/mainboard/google/veyron_mighty/mainboard.c b/src/mainboard/google/veyron_mighty/mainboard.c
index 540b23dc34..fb1d8fa69e 100644
--- a/src/mainboard/google/veyron_mighty/mainboard.c
+++ b/src/mainboard/google/veyron_mighty/mainboard.c
@@ -123,6 +123,7 @@ static void mainboard_init(device_t dev)
 	configure_vop();
 
 	elog_init();
+	elog_add_watchdog_reset();
 	elog_add_boot_reason();
 }