mediatek/mt8183: Add RTC support

This patch implements RTC initialization.
1. initialization dcxo
2. rtc clock using dcxo 32k
3. export RTC_32K1V8_0 to SOC, export RTC_32K1V8_1 to WLAN
4. rtc register initialization
5. refactor the driver common part

BUG=b:80501386
BRANCH=none
TEST=Boots correctly on Kukui

Change-Id: Icccb9360a507fcbfd865b107cd3630e71c810d55
Signed-off-by: Ran Bi <ran.bi@mediatek.com>
Reviewed-on: https://review.coreboot.org/c/31046
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Julius Werner <jwerner@chromium.org>

8 files changed, 718 insertions, 256 deletions

diff --git a/src/soc/mediatek/common/include/soc/rtc_common.h b/src/soc/mediatek/common/include/soc/rtc_common.h
new file mode 100644
index 0000000000..41e772e9ed
--- /dev/null
+++ b/src/soc/mediatek/common/include/soc/rtc_common.h
@@ -0,0 +1,105 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright 2018 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.
+ */
+
+#ifndef SOC_MEDIATEK_RTC_COMMON_H
+#define SOC_MEDIATEK_RTC_COMMON_H
+
+#include <assert.h>
+#include <bcd.h>
+#include <console/console.h>
+#include <delay.h>
+#include <rtc.h>
+#include <timer.h>
+
+/*
+ * Default values for RTC initialization
+ * Year (YEA)        : 1970 ~ 2037
+ * Month (MTH)       : 1 ~ 12
+ * Day of Month (DOM): 1 ~ 31
+ */
+
+enum {
+	RTC_DEFAULT_YEA = 2010,
+	RTC_DEFAULT_MTH = 1,
+	RTC_DEFAULT_DOM = 1,
+	RTC_DEFAULT_DOW = 5
+};
+
+enum {
+	RTC_2SEC_REBOOT_ENABLE  = 1,
+	RTC_2SEC_MODE   = 2
+};
+
+enum {
+	RTC_OSC32CON_UNLOCK1 = 0x1A57,
+	RTC_OSC32CON_UNLOCK2 = 0x2B68
+};
+
+enum {
+	RTC_PROT_UNLOCK1 = 0x586A,
+	RTC_PROT_UNLOCK2 = 0x9136
+};
+
+enum {
+	RTC_BBPU_KEY	= 0x43 << 8
+};
+
+enum {
+	RTC_IRQ_STA_AL	= 1U << 0,
+	RTC_IRQ_STA_TC	= 1U << 1,
+	RTC_IRQ_STA_LP	= 1U << 3
+};
+
+enum {
+	RTC_IRQ_EN_AL		= 1U << 0,
+	RTC_IRQ_EN_TC		= 1U << 1,
+	RTC_IRQ_EN_ONESHOT	= 1U << 2,
+	RTC_IRQ_EN_LP		= 1U << 3,
+	RTC_IRQ_EN_ONESHOT_AL	= RTC_IRQ_EN_ONESHOT | RTC_IRQ_EN_AL
+};
+
+enum {
+	RTC_POWERKEY1_KEY	= 0xA357,
+	RTC_POWERKEY2_KEY	= 0x67D2
+};
+
+enum {
+	RTC_SPAR0_32K_LESS	= 1U << 6
+};
+
+enum {
+	RTC_MIN_YEAR	= 1968,
+	RTC_BASE_YEAR	= 1900,
+	RTC_MIN_YEAR_OFFSET = RTC_MIN_YEAR - RTC_BASE_YEAR,
+
+	RTC_NUM_YEARS	= 128
+};
+
+enum {
+	RTC_STATE_REBOOT	= 0,
+	RTC_STATE_RECOVER	= 1,
+	RTC_STATE_INIT		= 2
+};
+
+/* external API */
+int rtc_busy_wait(void);
+int rtc_write_trigger(void);
+int rtc_writeif_unlock(void);
+void rtc_xosc_write(u16 val);
+int rtc_reg_init(void);
+u8 rtc_check_state(void);
+void rtc_boot_common(void);
+
+#endif /* SOC_MEDIATEK_RTC_COMMON_H */
diff --git a/src/soc/mediatek/common/rtc.c b/src/soc/mediatek/common/rtc.c
new file mode 100644
index 0000000000..fd40cb5d1a
--- /dev/null
+++ b/src/soc/mediatek/common/rtc.c
@@ -0,0 +1,194 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright 2018 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 <soc/rtc_common.h>
+#include <soc/rtc.h>
+#include <soc/pmic_wrap.h>
+
+/* ensure rtc write success */
+int rtc_busy_wait(void)
+{
+	struct stopwatch sw;
+	u16 bbpu;
+
+	stopwatch_init_usecs_expire(&sw, RTC_CBUSY_TIMEOUT_US);
+
+	do {
+		pwrap_read(RTC_BBPU, &bbpu);
+		/* Time > 1sec, time out and set recovery mode enable.*/
+		if (stopwatch_expired(&sw)) {
+			printk(BIOS_INFO, "[RTC] BBPU CBUSY time out !!\n");
+			return 0;
+		}
+	} while (bbpu & RTC_BBPU_CBUSY);
+
+	return 1;
+}
+
+int rtc_write_trigger(void)
+{
+	pwrap_write(RTC_WRTGR, 1);
+	return rtc_busy_wait();
+}
+
+/* unlock rtc write interface */
+int rtc_writeif_unlock(void)
+{
+	pwrap_write(RTC_PROT, RTC_PROT_UNLOCK1);
+	if (!rtc_write_trigger())
+		return 0;
+	pwrap_write(RTC_PROT, RTC_PROT_UNLOCK2);
+	if (!rtc_write_trigger())
+		return 0;
+
+	return 1;
+}
+
+/* set rtc time */
+int rtc_set(const struct rtc_time *time)
+{
+	return -1;
+}
+
+/* get rtc time */
+int rtc_get(struct rtc_time *time)
+{
+	u16 value;
+
+	pwrap_read(RTC_TC_SEC, &value);
+	time->sec = value;
+	pwrap_read(RTC_TC_MIN, &value);
+	time->min = value;
+	pwrap_read(RTC_TC_HOU, &value);
+	time->hour = value;
+	pwrap_read(RTC_TC_DOM, &value);
+	time->mday = value;
+	pwrap_read(RTC_TC_MTH, &value);
+	time->mon = value;
+	pwrap_read(RTC_TC_YEA, &value);
+	time->year = (value + RTC_MIN_YEAR_OFFSET) % 100;
+
+	return 0;
+}
+
+/* set rtc xosc setting */
+void rtc_xosc_write(u16 val)
+{
+	u16 bbpu;
+
+	pwrap_write(RTC_OSC32CON, RTC_OSC32CON_UNLOCK1);
+	udelay(200);
+	pwrap_write(RTC_OSC32CON, RTC_OSC32CON_UNLOCK2);
+	udelay(200);
+
+	pwrap_write(RTC_OSC32CON, val);
+	udelay(200);
+
+	pwrap_read(RTC_BBPU, &bbpu);
+	bbpu |= RTC_BBPU_KEY | RTC_BBPU_RELOAD;
+	pwrap_write(RTC_BBPU, bbpu);
+	rtc_write_trigger();
+}
+
+/* initialize rtc related registers */
+int rtc_reg_init(void)
+{
+	u16 irqsta;
+
+	pwrap_write(RTC_IRQ_EN, 0);
+	pwrap_write(RTC_CII_EN, 0);
+	pwrap_write(RTC_AL_MASK, 0);
+	pwrap_write(RTC_AL_YEA, 1970 - RTC_MIN_YEAR);
+	pwrap_write(RTC_AL_MTH, 1);
+	pwrap_write(RTC_AL_DOM, 1);
+	pwrap_write(RTC_AL_DOW, 4);
+	pwrap_write(RTC_AL_HOU, 0);
+	pwrap_write(RTC_AL_MIN, 0);
+	pwrap_write(RTC_AL_SEC, 0);
+
+	pwrap_write(RTC_DIFF, 0);
+	pwrap_write(RTC_CALI, 0);
+	if (!rtc_write_trigger())
+		return 0;
+
+	pwrap_read(RTC_IRQ_STA, &irqsta);  /* read clear */
+
+	/* init time counters after resetting RTC_DIFF and RTC_CALI */
+	pwrap_write(RTC_TC_YEA, RTC_DEFAULT_YEA - RTC_MIN_YEAR);
+	pwrap_write(RTC_TC_MTH, RTC_DEFAULT_MTH);
+	pwrap_write(RTC_TC_DOM, RTC_DEFAULT_DOM);
+	pwrap_write(RTC_TC_DOW, RTC_DEFAULT_DOW);
+	pwrap_write(RTC_TC_HOU, 0);
+	pwrap_write(RTC_TC_MIN, 0);
+	pwrap_write(RTC_TC_SEC, 0);
+
+	return rtc_write_trigger();
+}
+
+u8 rtc_check_state(void)
+{
+	u16 con;
+	u16 pwrky1;
+	u16 pwrky2;
+
+	pwrap_read(RTC_CON, &con);
+	pwrap_read(RTC_POWERKEY1, &pwrky1);
+	pwrap_read(RTC_POWERKEY2, &pwrky2);
+
+	if (con & RTC_CON_LPSTA_RAW)
+		return RTC_STATE_INIT;
+
+	if (!rtc_busy_wait())
+		return RTC_STATE_RECOVER;
+
+	if (!rtc_writeif_unlock())
+		return RTC_STATE_RECOVER;
+
+	if (pwrky1 != RTC_POWERKEY1_KEY || pwrky2 != RTC_POWERKEY2_KEY)
+		return RTC_STATE_INIT;
+	else
+		return RTC_STATE_REBOOT;
+}
+
+void rtc_boot_common(void)
+{
+	u16 bbpu;
+	u16 con;
+	u16 irqsta;
+
+	switch (rtc_check_state()) {
+	case RTC_STATE_REBOOT:
+		pwrap_write_field(RTC_BBPU, RTC_BBPU_KEY | RTC_BBPU_RELOAD,
+				  0xFFFF, 0);
+		rtc_write_trigger();
+		rtc_osc_init();
+		break;
+	case RTC_STATE_RECOVER:
+		rtc_init(1);
+		break;
+	case RTC_STATE_INIT:
+	default:
+		if (!rtc_init(0))
+			rtc_init(1);
+		break;
+	}
+
+	pwrap_read(RTC_IRQ_STA, &irqsta);  /* Read clear */
+	pwrap_read(RTC_BBPU, &bbpu);
+	pwrap_read(RTC_CON, &con);
+
+	printk(BIOS_INFO, "[RTC] irqsta = %x", irqsta);
+	printk(BIOS_INFO, " bbpu = %#x, con = %#x\n", bbpu, con);
+}
diff --git a/src/soc/mediatek/mt8173/Makefile.inc b/src/soc/mediatek/mt8173/Makefile.inc
index 4ccc218e4d..0ffa1965a9 100644
--- a/src/soc/mediatek/mt8173/Makefile.inc
+++ b/src/soc/mediatek/mt8173/Makefile.inc
@@ -60,7 +60,7 @@ romstage-y += memory.c
 romstage-y += emi.c dramc_pi_basic_api.c dramc_pi_calibration_api.c
 romstage-$(CONFIG_MEMORY_TEST) += ../common/memory_test.c
 romstage-y += ../common/mmu_operations.c mmu_operations.c
-romstage-y += rtc.c
+romstage-y += ../common/rtc.c rtc.c
 
 ################################################################################
 
@@ -77,7 +77,7 @@ ramstage-y += da9212.c
 ramstage-y += ../common/gpio.c gpio.c
 ramstage-y += ../common/wdt.c ../common/reset.c
 ramstage-y += ../common/pll.c pll.c
-ramstage-y += rtc.c
+ramstage-y += ../common/rtc.c rtc.c
 
 ramstage-y += ../common/usb.c usb.c
 
diff --git a/src/soc/mediatek/mt8173/include/soc/rtc.h b/src/soc/mediatek/mt8173/include/soc/rtc.h
index dd3546a13c..fe5cbac277 100644
--- a/src/soc/mediatek/mt8173/include/soc/rtc.h
+++ b/src/soc/mediatek/mt8173/include/soc/rtc.h
@@ -16,28 +16,10 @@
 #ifndef SOC_MEDIATEK_MT8173_RTC_H
 #define SOC_MEDIATEK_MT8173_RTC_H
 
+#include <soc/rtc_common.h>
 #include <stdint.h>
 #include "mt6391.h"
 
-/*
- * Default values for RTC initialization
- * Year (YEA)        : 1970 ~ 2037
- * Month (MTH)       : 1 ~ 12
- * Day of Month (DOM): 1 ~ 31
- */
-
-enum {
-	RTC_DEFAULT_YEA = 2010,
-	RTC_DEFAULT_MTH = 1,
-	RTC_DEFAULT_DOM = 1,
-	RTC_DEFAULT_DOW = 5
-};
-
-enum {
-	RTC_2SEC_REBOOT_ENABLE  = 1,
-	RTC_2SEC_MODE   = 2
-};
-
 /* RTC registers */
 enum {
 	RTC_BBPU = 0xE000,
@@ -89,16 +71,6 @@ enum {
 };
 
 enum {
-	RTC_OSC32CON_UNLOCK1 = 0x1A57,
-	RTC_OSC32CON_UNLOCK2 = 0x2B68
-};
-
-enum {
-	RTC_PROT_UNLOCK1 = 0x586A,
-	RTC_PROT_UNLOCK2 = 0x9136
-};
-
-enum {
 	RTC_BBPU_PWREN	= 1U << 0,
 	RTC_BBPU_BBPU	= 1U << 2,
 	RTC_BBPU_AUTO	= 1U << 3,
@@ -110,34 +82,11 @@ enum {
 };
 
 enum {
-	RTC_BBPU_KEY	= 0x43 << 8
-};
-
-enum {
-	RTC_IRQ_STA_AL	= 1U << 0,
-	RTC_IRQ_STA_TC	= 1U << 1,
-	RTC_IRQ_STA_LP	= 1U << 3
-};
-
-enum {
-	RTC_IRQ_EN_AL		= 1U << 0,
-	RTC_IRQ_EN_TC		= 1U << 1,
-	RTC_IRQ_EN_ONESHOT	= 1U << 2,
-	RTC_IRQ_EN_LP		= 1U << 3,
-	RTC_IRQ_EN_ONESHOT_AL	= RTC_IRQ_EN_ONESHOT | RTC_IRQ_EN_AL
-};
-
-enum {
 	RTC_OSC32CON_AMPEN	= 1U << 8,
 	RTC_OSC32CON_LNBUFEN	= 1U << 11
 };
 
 enum {
-	RTC_POWERKEY1_KEY	= 0xa357,
-	RTC_POWERKEY2_KEY	= 0x67d2
-};
-
-enum {
 	RTC_CON_LPEN		= 1U << 2,
 	RTC_CON_LPRST		= 1U << 3,
 	RTC_CON_CDBO		= 1U << 4,
@@ -161,24 +110,9 @@ enum {
 	RTC_CALI_BBPU_2SEC_STAT		= 1U << 11
 };
 
-enum {
-	RTC_SPAR0_32K_LESS	= 1U << 6
-};
-
-enum {
-	RTC_MIN_YEAR	= 1968,
-	RTC_BASE_YEAR	= 1900,
-	RTC_MIN_YEAR_OFFSET = RTC_MIN_YEAR - RTC_BASE_YEAR,
-
-	RTC_NUM_YEARS	= 128
-};
-
-enum {
-	RTC_STATE_REBOOT	= 0,
-	RTC_STATE_RECOVER	= 1,
-	RTC_STATE_INIT		= 2
-};
-
+/* external API */
+void rtc_osc_init(void);
+int rtc_init(u8 recover);
 void rtc_boot(void);
 
 #endif /* SOC_MEDIATEK_MT8173_RTC_H */
diff --git a/src/soc/mediatek/mt8173/rtc.c b/src/soc/mediatek/mt8173/rtc.c
index 153e9b4249..5b7d486d87 100644
--- a/src/soc/mediatek/mt8173/rtc.c
+++ b/src/soc/mediatek/mt8173/rtc.c
@@ -13,133 +13,13 @@
  * GNU General Public License for more details.
  */
 
-#include <assert.h>
-#include <bcd.h>
-#include <console/console.h>
-#include <delay.h>
-#include <rtc.h>
-#include <timer.h>
-
+#include <soc/rtc_common.h>
+#include <soc/rtc.h>
 #include <soc/mt6391.h>
 #include <soc/pmic_wrap.h>
-#include <soc/rtc.h>
 
 #define RTC_GPIO_USER_MASK	  ((1 << 13) - (1 << 8))
 
-/* ensure rtc write success */
-static inline int rtc_busy_wait(void)
-{
-	struct stopwatch sw;
-	u16 bbpu;
-
-	stopwatch_init_usecs_expire(&sw, RTC_CBUSY_TIMEOUT_US);
-
-	do {
-		pwrap_read(RTC_BBPU, &bbpu);
-		/* Time > 1sec, time out and set recovery mode enable.*/
-		if (stopwatch_expired(&sw)) {
-			printk(BIOS_INFO, "[RTC] BBPU CBUSY time out !!\n");
-			return 0;
-		}
-	} while (bbpu & RTC_BBPU_CBUSY);
-
-	return 1;
-}
-
-static int write_trigger(void)
-{
-	pwrap_write(RTC_WRTGR, 1);
-	return rtc_busy_wait();
-}
-
-/* unlock rtc write interface */
-static int writeif_unlock(void)
-{
-	pwrap_write(RTC_PROT, RTC_PROT_UNLOCK1);
-	if (!write_trigger())
-		return 0;
-	pwrap_write(RTC_PROT, RTC_PROT_UNLOCK2);
-	if (!write_trigger())
-		return 0;
-
-	return 1;
-}
-
-/* set rtc time */
-int rtc_set(const struct rtc_time *time)
-{
-	return -1;
-}
-
-/* get rtc time */
-int rtc_get(struct rtc_time *time)
-{
-	u16 value;
-
-	pwrap_read(RTC_TC_SEC, &value);
-	time->sec = value;
-	pwrap_read(RTC_TC_MIN, &value);
-	time->min = value;
-	pwrap_read(RTC_TC_HOU, &value);
-	time->hour = value;
-	pwrap_read(RTC_TC_DOM, &value);
-	time->mday = value;
-	pwrap_read(RTC_TC_MTH, &value);
-	time->mon = value;
-	pwrap_read(RTC_TC_YEA, &value);
-	time->year = (value + RTC_MIN_YEAR_OFFSET) % 100;
-
-	return 0;
-}
-
-/* set rtc xosc setting */
-static void rtc_xosc_write(u16 val)
-{
-	pwrap_write(RTC_OSC32CON, RTC_OSC32CON_UNLOCK1);
-	udelay(200);
-	pwrap_write(RTC_OSC32CON, RTC_OSC32CON_UNLOCK2);
-	udelay(200);
-
-	pwrap_write(RTC_OSC32CON, val);
-	udelay(200);
-	pwrap_write_field(RTC_BBPU, RTC_BBPU_KEY | RTC_BBPU_RELOAD, 0, 0);
-	write_trigger();
-}
-
-/* initialize rtc related registers */
-static int rtc_reg_init(void)
-{
-	u16 irqsta;
-
-	pwrap_write(RTC_IRQ_EN, 0);
-	pwrap_write(RTC_CII_EN, 0);
-	pwrap_write(RTC_AL_MASK, 0);
-	pwrap_write(RTC_AL_YEA, 1970 - RTC_MIN_YEAR);
-	pwrap_write(RTC_AL_MTH, 1);
-	pwrap_write(RTC_AL_DOM, 1);
-	pwrap_write(RTC_AL_DOW, 4);
-	pwrap_write(RTC_AL_HOU, 0);
-	pwrap_write(RTC_AL_MIN, 0);
-	pwrap_write(RTC_AL_SEC, 0);
-
-	pwrap_write(RTC_DIFF, 0);
-	pwrap_write(RTC_CALI, 0);
-	if (!write_trigger())
-		return 0;
-
-	pwrap_read(RTC_IRQ_STA, &irqsta);  /* read clear */
-
-	/* init time counters after resetting RTC_DIFF and RTC_CALI */
-	pwrap_write(RTC_TC_YEA, RTC_DEFAULT_YEA - RTC_MIN_YEAR);
-	pwrap_write(RTC_TC_MTH, RTC_DEFAULT_MTH);
-	pwrap_write(RTC_TC_DOM, RTC_DEFAULT_DOM);
-	pwrap_write(RTC_TC_DOW, RTC_DEFAULT_DOW);
-	pwrap_write(RTC_TC_HOU, 0);
-	pwrap_write(RTC_TC_MIN, 0);
-	pwrap_write(RTC_TC_SEC, 0);
-
-	return write_trigger();
-}
 
 /* initialize rtc related gpio */
 static int rtc_gpio_init(void)
@@ -155,11 +35,11 @@ static int rtc_gpio_init(void)
 	con |= (RTC_CON_GPEN | RTC_CON_GOE);
 	con &= ~(RTC_CON_F32KOB);
 	pwrap_write(RTC_CON, con);
-	return write_trigger();
+	return rtc_write_trigger();
 }
 
 /* set xosc mode */
-static void rtc_osc_init(void)
+void rtc_osc_init(void)
 {
 	u16 con;
 
@@ -176,26 +56,26 @@ static void rtc_osc_init(void)
 static int rtc_lpd_init(void)
 {
 	pwrap_write_field(RTC_CON, RTC_CON_LPEN, RTC_CON_LPRST, 0);
-	if (!write_trigger())
+	if (!rtc_write_trigger())
 		return 0;
 
 	pwrap_write_field(RTC_CON, RTC_CON_LPRST, 0, 0);
-	if (!write_trigger())
+	if (!rtc_write_trigger())
 		return 0;
 
 	pwrap_write_field(RTC_CON, 0, RTC_CON_LPRST, 0);
-	if (!write_trigger())
+	if (!rtc_write_trigger())
 		return 0;
 
 	return 1;
 }
 
 /* rtc init check */
-static int rtc_init(u8 recover)
+int rtc_init(u8 recover)
 {
 	printk(BIOS_INFO, "[RTC] %s recovery: %d\n", __func__, recover);
 
-	if (!writeif_unlock())
+	if (!rtc_writeif_unlock())
 		return 0;
 
 	if (!rtc_gpio_init())
@@ -213,7 +93,7 @@ static int rtc_init(u8 recover)
 	/* write powerkeys */
 	pwrap_write(RTC_POWERKEY1, RTC_POWERKEY1_KEY);
 	pwrap_write(RTC_POWERKEY2, RTC_POWERKEY2_KEY);
-	if (!write_trigger())
+	if (!rtc_write_trigger())
 		return 0;
 
 	if (recover)
@@ -238,8 +118,8 @@ static void rtc_bbpu_power_on(void)
 	/* pull PWRBB high */
 	bbpu = RTC_BBPU_KEY | RTC_BBPU_AUTO | RTC_BBPU_BBPU | RTC_BBPU_PWREN;
 	pwrap_write(RTC_BBPU, bbpu);
-	ret = write_trigger();
-	printk(BIOS_INFO, "[RTC] %s write_trigger=%d\n", __func__, ret);
+	ret = rtc_write_trigger();
+	printk(BIOS_INFO, "[RTC] %s rtc_write_trigger=%d\n", __func__, ret);
 
 	/* enable DCXO to transform external 32KHz clock to 26MHz clock
 	   directly sent to SoC */
@@ -256,63 +136,12 @@ static void rtc_bbpu_power_on(void)
 	pwrap_write_field(PMIC_RG_TOP_CKPDN2, 0x1, 0, 14);
 }
 
-static u8 rtc_check_state(void)
-{
-	u16 con;
-	u16 pwrky1;
-	u16 pwrky2;
-
-	pwrap_read(RTC_CON, &con);
-	pwrap_read(RTC_POWERKEY1, &pwrky1);
-	pwrap_read(RTC_POWERKEY2, &pwrky2);
-
-	if (con & RTC_CON_LPSTA_RAW)
-		return RTC_STATE_INIT;
-
-	if (!rtc_busy_wait())
-		return RTC_STATE_RECOVER;
-
-	if (!writeif_unlock())
-		return RTC_STATE_RECOVER;
-
-	if (pwrky1 != RTC_POWERKEY1_KEY || pwrky2 != RTC_POWERKEY2_KEY)
-		return RTC_STATE_INIT;
-	else
-		return RTC_STATE_REBOOT;
-}
-
 /* the rtc boot flow entry */
 void rtc_boot(void)
 {
-	u16 bbpu;
-	u16 con;
-	u16 irqsta;
-
 	pwrap_write(PMIC_RG_TOP_CKPDN, 0);
 	pwrap_write(PMIC_RG_TOP_CKPDN2, 0);
 
-	switch (rtc_check_state()) {
-	case RTC_STATE_REBOOT:
-		pwrap_write_field(RTC_BBPU, RTC_BBPU_KEY | RTC_BBPU_RELOAD, 0,
-				  0);
-		write_trigger();
-		rtc_osc_init();
-		break;
-	case RTC_STATE_RECOVER:
-		rtc_init(1);
-		break;
-	case RTC_STATE_INIT:
-	default:
-		if (!rtc_init(0))
-			rtc_init(1);
-		break;
-	}
-
-	pwrap_read(RTC_IRQ_STA, &irqsta);  /* Read clear */
-	pwrap_read(RTC_BBPU, &bbpu);
-	pwrap_read(RTC_CON, &con);
-
-	printk(BIOS_INFO, "[RTC] irqsta = %x", irqsta);
-	printk(BIOS_INFO, " bbpu = %#x, con = %#x\n", bbpu, con);
+	rtc_boot_common();
 	rtc_bbpu_power_on();
 }
diff --git a/src/soc/mediatek/mt8183/Makefile.inc b/src/soc/mediatek/mt8183/Makefile.inc
index 5770a83d06..3fce0a81fd 100644
--- a/src/soc/mediatek/mt8183/Makefile.inc
+++ b/src/soc/mediatek/mt8183/Makefile.inc
@@ -33,6 +33,7 @@ romstage-y += mt8183.c
 romstage-y += ../common/gpio.c gpio.c
 romstage-y += ../common/mmu_operations.c mmu_operations.c
 romstage-y += ../common/pmic_wrap.c pmic_wrap.c mt6358.c
+romstage-y += ../common/rtc.c rtc.c
 romstage-$(CONFIG_SPI_FLASH) += ../common/spi.c spi.c
 romstage-y += ../common/timer.c
 romstage-y += ../common/uart.c
diff --git a/src/soc/mediatek/mt8183/include/soc/rtc.h b/src/soc/mediatek/mt8183/include/soc/rtc.h
new file mode 100644
index 0000000000..65604a13c2
--- /dev/null
+++ b/src/soc/mediatek/mt8183/include/soc/rtc.h
@@ -0,0 +1,149 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright 2018 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.
+ */
+
+#ifndef SOC_MEDIATEK_MT8183_RTC_H
+#define SOC_MEDIATEK_MT8183_RTC_H
+
+#include <soc/rtc_common.h>
+#include <halt.h>
+
+/* RTC registers */
+enum {
+	RTC_BBPU = 0x0588,
+	RTC_IRQ_STA = 0x058A,
+	RTC_IRQ_EN = 0x058C,
+	RTC_CII_EN = 0x058E
+};
+
+enum {
+	RTC_TC_SEC = 0x0592,
+	RTC_TC_MIN = 0x0594,
+	RTC_TC_HOU = 0x0596,
+	RTC_TC_DOM = 0x0598,
+	RTC_TC_DOW = 0x059A,
+	RTC_TC_MTH = 0x059C,
+	RTC_TC_YEA = 0x059E
+};
+
+enum {
+	RTC_AL_SEC = 0x05A0,
+	RTC_AL_MIN = 0x05A2,
+	RTC_AL_HOU = 0x05A4,
+	RTC_AL_DOM = 0x05A6,
+	RTC_AL_DOW = 0x05A8,
+	RTC_AL_MTH = 0x05AA,
+	RTC_AL_YEA = 0x05AC,
+	RTC_AL_MASK = 0x0590
+};
+
+enum {
+	RTC_OSC32CON = 0x05AE,
+	RTC_CON = 0x05C4,
+	RTC_WRTGR = 0x05C2
+};
+
+enum {
+	RTC_POWERKEY1 = 0x05B0,
+	RTC_POWERKEY2 = 0x05B2
+};
+
+enum {
+	RTC_PDN1 = 0x05B4,
+	RTC_PDN2 = 0x05B6,
+	RTC_SPAR0 = 0x05B8,
+	RTC_SPAR1 = 0x05BA,
+	RTC_PROT = 0x05BC,
+	RTC_DIFF = 0x05BE,
+	RTC_CALI = 0x05C0
+};
+
+enum {
+	RTC_BBPU_PWREN	= 1U << 0,
+	RTC_BBPU_CLR	= 1U << 1,
+	RTC_BBPU_INIT	= 1U << 2,
+	RTC_BBPU_AUTO	= 1U << 3,
+	RTC_BBPU_CLRPKY	= 1U << 4,
+	RTC_BBPU_RELOAD	= 1U << 5,
+	RTC_BBPU_CBUSY	= 1U << 6,
+
+	RTC_CBUSY_TIMEOUT_US = 800
+};
+
+enum {
+	RTC_CON_VBAT_LPSTA_RAW	= 1U << 0,
+	RTC_CON_EOSC32_LPEN	= 1U << 1,
+	RTC_CON_XOSC32_LPEN	= 1U << 2,
+	RTC_CON_LPRST		= 1U << 3,
+	RTC_CON_CDBO		= 1U << 4,
+	RTC_CON_F32KOB		= 1U << 5,
+	RTC_CON_GPO		= 1U << 6,
+	RTC_CON_GOE		= 1U << 7,
+	RTC_CON_GSR		= 1U << 8,
+	RTC_CON_GSMT		= 1U << 9,
+	RTC_CON_GPEN		= 1U << 10,
+	RTC_CON_GPU		= 1U << 11,
+	RTC_CON_GE4		= 1U << 12,
+	RTC_CON_GE8		= 1U << 13,
+	RTC_CON_GPI		= 1U << 14,
+	RTC_CON_LPSTA_RAW	= 1U << 15
+};
+
+enum {
+	RTC_EMBCK_SRC_SEL	= 1 << 8,
+	RTC_EMBCK_SEL_MODE	= 3 << 6,
+	RTC_XOSC32_ENB		= 1 << 5,
+	RTC_REG_XOSC32_ENB	= 1 << 15
+};
+
+/* PMIC TOP Register Definition */
+enum {
+	PMIC_RG_SCK_TOP_CON0 = 0x050C
+};
+
+/* PMIC TOP Register Definition */
+enum {
+	PMIC_RG_TOP_CKPDN_CON1 = 0x0112,
+	PMIC_RG_TOP_CKPDN_CON1_SET = 0x0114,
+	PMIC_RG_TOP_CKPDN_CON1_CLR = 0x0116,
+	PMIC_RG_TOP_CKSEL_CON0 = 0x0118,
+	PMIC_RG_TOP_CKSEL_CON0_SET = 0x011A,
+	PMIC_RG_TOP_CKSEL_CON0_CLR = 0x011C
+};
+
+/* PMIC DCXO Register Definition */
+enum {
+	PMIC_RG_DCXO_CW00 = 0x0788,
+	PMIC_RG_DCXO_CW02 = 0x0790,
+	PMIC_RG_DCXO_CW07 = 0x079A,
+	PMIC_RG_DCXO_CW09 = 0x079E,
+	PMIC_RG_DCXO_CW11 = 0x07A2,
+	PMIC_RG_DCXO_CW13 = 0x07AA,
+	PMIC_RG_DCXO_CW15 = 0x07AE,
+	PMIC_RG_DCXO_CW16 = 0x07B0,
+	PMIC_RG_DCXO_CW21 = 0x07BA,
+	PMIC_RG_DCXO_ELR0 = 0x07C4
+};
+
+enum {
+	PMIC_RG_TOP_TMA_KEY = 0x03A8
+};
+
+/* external API */
+void rtc_bbpu_power_on(void);
+void rtc_osc_init(void);
+int rtc_init(u8 recover);
+void rtc_boot(void);
+
+#endif /* SOC_MEDIATEK_MT8183_RTC_H */
diff --git a/src/soc/mediatek/mt8183/rtc.c b/src/soc/mediatek/mt8183/rtc.c
new file mode 100644
index 0000000000..64eedfb552
--- /dev/null
+++ b/src/soc/mediatek/mt8183/rtc.c
@@ -0,0 +1,250 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright 2018 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 <soc/rtc_common.h>
+#include <soc/rtc.h>
+#include <soc/mt6358.h>
+#include <soc/pmic_wrap.h>
+
+#define RTC_GPIO_USER_MASK	  ((1 << 13) - (1 << 8))
+
+/* initialize rtc setting of using dcxo clock */
+static void rtc_enable_dcxo(void)
+{
+	u16 bbpu, con, osc32con, sec;
+
+	pwrap_read(RTC_BBPU, &bbpu);
+	pwrap_write(RTC_BBPU, bbpu | RTC_BBPU_KEY | RTC_BBPU_RELOAD);
+	rtc_write_trigger();
+
+	mdelay(1);
+	if (!rtc_writeif_unlock()) /* Unlock for reload */
+		printk(BIOS_INFO,
+			"[RTC] %s rtc_writeif_unlock() fail\n", __func__);
+
+	pwrap_read(RTC_OSC32CON, &osc32con);
+	rtc_xosc_write((osc32con & ~RTC_EMBCK_SRC_SEL)
+			| RTC_XOSC32_ENB | RTC_REG_XOSC32_ENB);
+	pwrap_read(RTC_BBPU, &bbpu);
+	pwrap_write(RTC_BBPU, bbpu | RTC_BBPU_KEY | RTC_BBPU_RELOAD);
+	rtc_write_trigger();
+
+	pwrap_read(RTC_CON, &con);
+	pwrap_read(RTC_OSC32CON, &osc32con);
+	pwrap_read(RTC_AL_SEC, &sec);
+	printk(BIOS_INFO, "[RTC] %s con = 0x%x, osc32con = 0x%x, sec = 0x%x\n",
+		__func__, con, osc32con, sec);
+}
+
+/* initialize rtc related gpio */
+static int rtc_gpio_init(void)
+{
+	u16 con;
+
+	/* RTC_32K1V8 clock change from 128k div 4 source
+	 * to RTC 32k source
+	 */
+	pwrap_write_field(PMIC_RG_TOP_CKSEL_CON0_SET, 0x1, 0x1, 3);
+
+	/* Export 32K clock RTC_32K1V8_1 */
+	pwrap_write_field(PMIC_RG_TOP_CKPDN_CON1_CLR, 0x1, 0x1, 1);
+
+	/* Export 32K clock RTC_32K2V8 */
+	pwrap_read(RTC_CON, &con);
+	con &= (RTC_CON_LPSTA_RAW | RTC_CON_LPRST | RTC_CON_EOSC32_LPEN);
+	con |= (RTC_CON_GPEN | RTC_CON_GOE);
+	con &= ~(RTC_CON_F32KOB);
+	pwrap_write(RTC_CON, con);
+	return rtc_write_trigger();
+}
+
+/* set xosc mode */
+void rtc_osc_init(void)
+{
+	/* enable 32K export */
+	rtc_gpio_init();
+}
+
+/* low power detect setting */
+static int rtc_lpd_init(void)
+{
+	u16 con;
+
+	con = pwrap_read(RTC_CON, &con) | RTC_CON_XOSC32_LPEN;
+	con &= ~RTC_CON_LPRST;
+	pwrap_write(RTC_CON, con);
+	if (!rtc_write_trigger())
+		return 0;
+
+	con |= RTC_CON_LPRST;
+	pwrap_write(RTC_CON, con);
+	if (!rtc_write_trigger())
+		return 0;
+
+	con &= ~RTC_CON_LPRST;
+	pwrap_write(RTC_CON, con);
+	if (!rtc_write_trigger())
+		return 0;
+
+	con = pwrap_read(RTC_CON, &con) | RTC_CON_EOSC32_LPEN;
+	con &= ~RTC_CON_LPRST;
+	pwrap_write(RTC_CON, con);
+	if (!rtc_write_trigger())
+		return 0;
+
+	con |= RTC_CON_LPRST;
+	pwrap_write(RTC_CON, con);
+	if (!rtc_write_trigger())
+		return 0;
+
+	con &= ~RTC_CON_LPRST;
+	pwrap_write(RTC_CON, con);
+	if (!rtc_write_trigger())
+		return 0;
+
+	return 1;
+}
+
+static bool rtc_hw_init(void)
+{
+	u16 bbpu;
+
+	pwrap_read(RTC_BBPU, &bbpu);
+	pwrap_write(RTC_BBPU, bbpu | RTC_BBPU_KEY | RTC_BBPU_INIT);
+	rtc_write_trigger();
+
+	udelay(500);
+
+	pwrap_read(RTC_BBPU, &bbpu);
+	pwrap_write(RTC_BBPU, bbpu | RTC_BBPU_KEY | RTC_BBPU_RELOAD);
+	rtc_write_trigger();
+
+	pwrap_read(RTC_BBPU, &bbpu);
+	if (bbpu & RTC_BBPU_INIT) {
+		printk(BIOS_INFO, "[RTC] %s:%d timeout\n", __func__, __LINE__);
+		return false;
+	}
+
+	return true;
+}
+
+/* rtc init check */
+int rtc_init(u8 recover)
+{
+	printk(BIOS_INFO, "[RTC] %s recovery: %d\n", __func__, recover);
+
+	if (!rtc_writeif_unlock())
+		return 0;
+
+	if (!rtc_gpio_init())
+		return 0;
+
+	/* using dcxo 32K clock */
+	rtc_enable_dcxo();
+
+	if (recover)
+		mdelay(20);
+
+	/* write powerkeys */
+	pwrap_write(RTC_POWERKEY1, RTC_POWERKEY1_KEY);
+	pwrap_write(RTC_POWERKEY2, RTC_POWERKEY2_KEY);
+	if (!rtc_write_trigger())
+		return 0;
+
+	if (!rtc_reg_init())
+		return 0;
+	if (!rtc_lpd_init())
+		return 0;
+	if (!rtc_hw_init())
+		return 0;
+
+	return 1;
+}
+
+/* enable rtc bbpu */
+void rtc_bbpu_power_on(void)
+{
+	u16 bbpu;
+	int ret;
+
+	/* pull powerhold high, control by pmic */
+	pmic_set_power_hold(true);
+
+	/* pull PWRBB high */
+	bbpu = RTC_BBPU_KEY | RTC_BBPU_AUTO | RTC_BBPU_RELOAD | RTC_BBPU_PWREN;
+	pwrap_write(RTC_BBPU, bbpu);
+	ret = rtc_write_trigger();
+	printk(BIOS_INFO, "[RTC] %s rtc_write_trigger=%d\n", __func__, ret);
+
+	pwrap_read(RTC_BBPU, &bbpu);
+	printk(BIOS_INFO, "[RTC] %s done BBPU=%#x\n", __func__, bbpu);
+}
+
+void poweroff(void)
+{
+	u16 bbpu;
+
+	if (!rtc_writeif_unlock())
+		printk(BIOS_INFO,
+			"[RTC] %s rtc_writeif_unlock() fail\n", __func__);
+	/* pull PWRBB low */
+	bbpu = RTC_BBPU_KEY | RTC_BBPU_RELOAD | RTC_BBPU_PWREN;
+	pwrap_write(RTC_BBPU, bbpu);
+
+	pmic_set_power_hold(false);
+	halt();
+}
+
+static void dcxo_init(void)
+{
+	/* Buffer setting */
+	pwrap_write(PMIC_RG_DCXO_CW15, 0xA2AA);
+	pwrap_write(PMIC_RG_DCXO_CW13, 0x98E9);
+	pwrap_write(PMIC_RG_DCXO_CW16, 0x9855);
+
+	/* 26M enable control */
+	/* Enable clock buffer XO_SOC, XO_CEL */
+	pwrap_write(PMIC_RG_DCXO_CW00, 0x4805);
+	pwrap_write(PMIC_RG_DCXO_CW11, 0x8000);
+
+	/* Load thermal coefficient */
+	pwrap_write(PMIC_RG_TOP_TMA_KEY, 0x9CA7);
+	pwrap_write(PMIC_RG_DCXO_CW21, 0x12A7);
+	pwrap_write(PMIC_RG_DCXO_ELR0, 0xD004);
+	pwrap_write(PMIC_RG_TOP_TMA_KEY, 0x0000);
+
+	/* Adjust OSC FPM setting */
+	pwrap_write(PMIC_RG_DCXO_CW07, 0x8FFE);
+
+	/* Re-Calibrate OSC current */
+	pwrap_write(PMIC_RG_DCXO_CW09, 0x008F);
+	udelay(100);
+	pwrap_write(PMIC_RG_DCXO_CW09, 0x408F);
+	mdelay(5);
+}
+
+/* the rtc boot flow entry */
+void rtc_boot(void)
+{
+	/* dcxo clock init settings */
+	dcxo_init();
+
+	/* dcxo 32k init settings */
+	pwrap_write_field(PMIC_RG_DCXO_CW02, 0xF, 0xF, 0);
+	pwrap_write_field(PMIC_RG_SCK_TOP_CON0, 0x1, 0x1, 0);
+
+	rtc_boot_common();
+	rtc_bbpu_power_on();
+}