mediatek: Separate WDT reset function from WDT driver

Separate WDT reset function from WDT driver, then we can use the common
WDT driver and have a board-specific reset function on different boards.

In Kukui, we plan to use GPIO HW reset, instead of WDT reset. Add config
"MISSING_BOARD_RESET" in Kukui to pass the build for now.

BUG=b:80501386
BRANCH=none
TEST=emerge-elm coreboot; emerge-kukui coreboot;

Change-Id: Ica07fe3a027cd7e9eb6d10202c3ef3ed7bea00c2
Signed-off-by: Tristan Shieh <tristan.shieh@mediatek.com>
Reviewed-on: https://review.coreboot.org/c/31121
Reviewed-by: Julius Werner <jwerner@chromium.org>
Reviewed-by: Hung-Te Lin <hungte@chromium.org>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/mainboard/google/kukui/Kconfig

@@ -37,6 +37,7 @@ config BOARD_SPECIFIC_OPTIONS
 	select EC_GOOGLE_CHROMEEC_SPI
 	select MAINBOARD_HAS_SPI_TPM_CR50 if VBOOT
 	select MAINBOARD_HAS_TPM2 if VBOOT
+	select MISSING_BOARD_RESET
 
 config MAINBOARD_DIR
 	string

src/soc/mediatek/common/include/soc/wdt.h

@@ -17,6 +17,7 @@
 #define SOC_MEDIATEK_COMMON_WDT_H
 
 #include <stdint.h>
+#include <soc/addressmap.h>
 
 struct mtk_wdt_regs {
 	u32 wdt_mode;
@@ -48,6 +49,8 @@ enum {
 	MTK_WDT_STA_HW_RST	= 1 << 31
 };
 
+static struct mtk_wdt_regs *const mtk_wdt = (void *)RGU_BASE;
+
 int mtk_wdt_init(void);
 
 #endif /* SOC_MEDIATEK_COMMON_WDT_H */

src/soc/mediatek/common/reset.c

@@ -0,0 +1,23 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright 2019 MediaTek Inc.
+ *
+ * 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.
+ */
+
+#include <arch/io.h>
+#include <reset.h>
+#include <soc/wdt.h>
+
+void do_board_reset(void)
+{
+	write32(&mtk_wdt->wdt_swrst, MTK_WDT_SWRST_KEY);
+}

src/soc/mediatek/common/wdt.c

@@ -15,13 +15,9 @@
 
 #include <arch/io.h>
 #include <console/console.h>
-#include <reset.h>
-#include <soc/addressmap.h>
 #include <soc/wdt.h>
 #include <vendorcode/google/chromeos/chromeos.h>
 
-static struct mtk_wdt_regs *const mtk_wdt = (void *)RGU_BASE;
-
 int mtk_wdt_init(void)
 {
 	uint32_t wdt_sta;
@@ -56,8 +52,3 @@ int mtk_wdt_init(void)
 
 	return wdt_sta;
 }
-
-void do_board_reset(void)
-{
-	write32(&mtk_wdt->wdt_swrst, MTK_WDT_SWRST_KEY);
-}

src/soc/mediatek/mt8173/Makefile.inc

@@ -27,7 +27,7 @@ bootblock-y += ../common/uart.c
 
 bootblock-y += ../common/gpio.c gpio.c gpio_init.c
 bootblock-y +=  ../common/pmic_wrap.c pmic_wrap.c mt6391.c
-bootblock-y += ../common/wdt.c
+bootblock-y += ../common/wdt.c ../common/reset.c
 bootblock-y += ../common/mmu_operations.c mmu_operations.c
 
 ################################################################################
@@ -39,7 +39,7 @@ verstage-y += ../common/uart.c
 
 verstage-y += ../common/timer.c
 verstage-y += timer.c
-verstage-y += ../common/wdt.c
+verstage-y += ../common/wdt.c ../common/reset.c
 verstage-$(CONFIG_SPI_FLASH) += flash_controller.c
 verstage-y += ../common/gpio.c gpio.c
 
@@ -75,7 +75,7 @@ ramstage-y += ../common/pmic_wrap.c pmic_wrap.c mt6391.c i2c.c
 ramstage-y += mt6311.c
 ramstage-y += da9212.c
 ramstage-y += ../common/gpio.c gpio.c
-ramstage-y += ../common/wdt.c
+ramstage-y += ../common/wdt.c ../common/reset.c
 ramstage-y += ../common/pll.c pll.c
 ramstage-y += rtc.c