soc/mediatek/common: Add halt() after triggering wdt reset

It's more reasonable to halt when we trigger watchdog reset because
the whole system should be reset afterwards.

BUG=b:222217317
TEST=build pass

Signed-off-by: Rex-BC Chen <rex-bc.chen@mediatek.com>
Change-Id: I726ba1599841f63b37062f9ce2e04840e4f250bb
Reviewed-on: https://review.coreboot.org/c/coreboot/+/62752
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Yu-Ping Wu <yupingso@google.com>

1 files changed, 21 insertions, 11 deletions

diff --git a/src/soc/mediatek/common/wdt.c b/src/soc/mediatek/common/wdt.c
index 4f8eff282e..108648f80f 100644
--- a/src/soc/mediatek/common/wdt.c
+++ b/src/soc/mediatek/common/wdt.c
@@ -3,11 +3,31 @@
 #include <arch/cache.h>
 #include <device/mmio.h>
 #include <console/console.h>
+#include <halt.h>
 #include <soc/wdt.h>
 #include <vendorcode/google/chromeos/chromeos.h>
 
 __weak void mtk_wdt_clr_status(void) { /* do nothing */ }
 
+static inline void mtk_wdt_swreset(void)
+{
+	/*
+	 * We trigger a secondary reset by triggering WDT hardware to send the
+	 * signal to EC.
+	 * We do not use do_board_reset() to send the signal to EC which is
+	 * controlled by software driver.
+	 * Before triggering the secondary reset, clean the data cache so the
+	 * logs in cbmem console (either in SRAM or DRAM) can be flushed.
+	 */
+	printk(BIOS_INFO, "%s() called!\n", __func__);
+
+	dcache_clean_all();
+	setbits32(&mtk_wdt->wdt_mode, MTK_WDT_MODE_EXTEN | MTK_WDT_MODE_KEY);
+	write32(&mtk_wdt->wdt_swrst, MTK_WDT_SWRST_KEY);
+
+	halt();
+}
+
 int mtk_wdt_init(void)
 {
 	uint32_t wdt_sta;
@@ -23,17 +43,7 @@ int mtk_wdt_init(void)
 	if (wdt_sta & MTK_WDT_STA_HW_RST) {
 		printk(BIOS_INFO, "hardware watchdog\n");
 		mark_watchdog_tombstone();
-
-		/*
-		 * We trigger secondary reset by triggering WDT hardware to send signal to EC.
-		 * We do not use do_board_reset() to send signal to EC
-		 * which is controlled by software driver.
-		 * Before triggering secondary reset, clean the data cache so the logs in cbmem
-		 * console (either in SRAM or DRAM) can be flushed.
-		 */
-		dcache_clean_all();
-		setbits32(&mtk_wdt->wdt_mode, MTK_WDT_MODE_EXTEN | MTK_WDT_MODE_KEY);
-		write32(&mtk_wdt->wdt_swrst, MTK_WDT_SWRST_KEY);
+		mtk_wdt_swreset();
 	} else if (wdt_sta & MTK_WDT_STA_SW_RST)
 		printk(BIOS_INFO, "normal software reboot\n");
 	else if (wdt_sta & MTK_WDT_STA_SPM_RST)