Merge changes I2b3aa9bd,I3237199b into integration

* changes:
  docs: add mt6795 to deprecated list
  feat(plat/mediatek/mt8195): add DCM driver
diff --git a/docs/plat/deprecated.rst b/docs/plat/deprecated.rst
index 203ae00..7cc4258 100644
--- a/docs/plat/deprecated.rst
+++ b/docs/plat/deprecated.rst
@@ -16,3 +16,5 @@
 +================+================+====================+====================+
 |    sgm775      |      Arm       |        2.5         |       2.7          |
 +----------------+----------------+--------------------+--------------------+
+|    mt6795      |      MTK       |        2.5         |       2.7          |
++----------------+----------------+--------------------+--------------------+
diff --git a/plat/mediatek/mt8195/bl31_plat_setup.c b/plat/mediatek/mt8195/bl31_plat_setup.c
index 39c1918..8745454 100644
--- a/plat/mediatek/mt8195/bl31_plat_setup.c
+++ b/plat/mediatek/mt8195/bl31_plat_setup.c
@@ -19,6 +19,7 @@
 #include <mt_gic_v3.h>
 #include <mt_spm.h>
 #include <mt_timer.h>
+#include <mtk_dcm.h>
 #include <mtgpio.h>
 #include <plat_params.h>
 #include <plat_private.h>
@@ -84,6 +85,11 @@
  ******************************************************************************/
 void bl31_platform_setup(void)
 {
+	/* Set dcm on */
+	if (!dcm_set_default()) {
+		ERROR("Failed to set default dcm on!!\n");
+	}
+
 	/* Initialize the GIC driver, CPU and distributor interfaces */
 	mt_gic_driver_init();
 	mt_gic_init();
diff --git a/plat/mediatek/mt8195/drivers/dcm/mtk_dcm.c b/plat/mediatek/mt8195/drivers/dcm/mtk_dcm.c
new file mode 100644
index 0000000..aed0833
--- /dev/null
+++ b/plat/mediatek/mt8195/drivers/dcm/mtk_dcm.c
@@ -0,0 +1,63 @@
+/*
+ * Copyright (c) 2021, MediaTek Inc. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <mtk_dcm.h>
+#include <mtk_dcm_utils.h>
+
+static void dcm_armcore(bool mode)
+{
+	dcm_mp_cpusys_top_bus_pll_div_dcm(mode);
+	dcm_mp_cpusys_top_cpu_pll_div_0_dcm(mode);
+	dcm_mp_cpusys_top_cpu_pll_div_1_dcm(mode);
+}
+
+static void dcm_mcusys(bool on)
+{
+	dcm_mp_cpusys_top_adb_dcm(on);
+	dcm_mp_cpusys_top_apb_dcm(on);
+	dcm_mp_cpusys_top_cpubiu_dcm(on);
+	dcm_mp_cpusys_top_misc_dcm(on);
+	dcm_mp_cpusys_top_mp0_qdcm(on);
+	dcm_cpccfg_reg_emi_wfifo(on);
+	dcm_mp_cpusys_top_last_cor_idle_dcm(on);
+}
+
+static void dcm_stall(bool on)
+{
+	dcm_mp_cpusys_top_core_stall_dcm(on);
+	dcm_mp_cpusys_top_fcm_stall_dcm(on);
+}
+
+static bool check_dcm_state(void)
+{
+	bool ret = true;
+
+	ret &= dcm_mp_cpusys_top_bus_pll_div_dcm_is_on();
+	ret &= dcm_mp_cpusys_top_cpu_pll_div_0_dcm_is_on();
+	ret &= dcm_mp_cpusys_top_cpu_pll_div_1_dcm_is_on();
+
+	ret &= dcm_mp_cpusys_top_adb_dcm_is_on();
+	ret &= dcm_mp_cpusys_top_apb_dcm_is_on();
+	ret &= dcm_mp_cpusys_top_cpubiu_dcm_is_on();
+	ret &= dcm_mp_cpusys_top_misc_dcm_is_on();
+	ret &= dcm_mp_cpusys_top_mp0_qdcm_is_on();
+	ret &= dcm_cpccfg_reg_emi_wfifo_is_on();
+	ret &= dcm_mp_cpusys_top_last_cor_idle_dcm_is_on();
+
+	ret &= dcm_mp_cpusys_top_core_stall_dcm_is_on();
+	ret &= dcm_mp_cpusys_top_fcm_stall_dcm_is_on();
+
+	return ret;
+}
+
+bool dcm_set_default(void)
+{
+	dcm_armcore(true);
+	dcm_mcusys(true);
+	dcm_stall(true);
+
+	return check_dcm_state();
+}
diff --git a/plat/mediatek/mt8195/drivers/dcm/mtk_dcm.h b/plat/mediatek/mt8195/drivers/dcm/mtk_dcm.h
new file mode 100644
index 0000000..cb65b85
--- /dev/null
+++ b/plat/mediatek/mt8195/drivers/dcm/mtk_dcm.h
@@ -0,0 +1,14 @@
+/*
+ * Copyright (c) 2021, MediaTek Inc. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef MTK_DCM_H
+#define MTK_DCM_H
+
+#include <stdbool.h>
+
+bool dcm_set_default(void);
+
+#endif /* #ifndef MTK_DCM_H */
diff --git a/plat/mediatek/mt8195/drivers/dcm/mtk_dcm_utils.c b/plat/mediatek/mt8195/drivers/dcm/mtk_dcm_utils.c
new file mode 100644
index 0000000..a1a3720
--- /dev/null
+++ b/plat/mediatek/mt8195/drivers/dcm/mtk_dcm_utils.c
@@ -0,0 +1,483 @@
+/*
+ * Copyright (c) 2021, MediaTek Inc. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <lib/mmio.h>
+#include <lib/utils_def.h>
+#include <mtk_dcm_utils.h>
+
+#define MP_CPUSYS_TOP_ADB_DCM_REG0_MASK (BIT(17))
+#define MP_CPUSYS_TOP_ADB_DCM_REG1_MASK (BIT(15) | \
+			BIT(16) | \
+			BIT(17) | \
+			BIT(18) | \
+			BIT(21))
+#define MP_CPUSYS_TOP_ADB_DCM_REG2_MASK (BIT(15) | \
+			BIT(16) | \
+			BIT(17) | \
+			BIT(18))
+#define MP_CPUSYS_TOP_ADB_DCM_REG0_ON (BIT(17))
+#define MP_CPUSYS_TOP_ADB_DCM_REG1_ON (BIT(15) | \
+			BIT(16) | \
+			BIT(17) | \
+			BIT(18) | \
+			BIT(21))
+#define MP_CPUSYS_TOP_ADB_DCM_REG2_ON (BIT(15) | \
+			BIT(16) | \
+			BIT(17) | \
+			BIT(18))
+#define MP_CPUSYS_TOP_ADB_DCM_REG0_OFF ((0x0 << 17))
+#define MP_CPUSYS_TOP_ADB_DCM_REG1_OFF ((0x0 << 15) | \
+			(0x0 << 16) | \
+			(0x0 << 17) | \
+			(0x0 << 18) | \
+			(0x0 << 21))
+#define MP_CPUSYS_TOP_ADB_DCM_REG2_OFF ((0x0 << 15) | \
+			(0x0 << 16) | \
+			(0x0 << 17) | \
+			(0x0 << 18))
+
+bool dcm_mp_cpusys_top_adb_dcm_is_on(void)
+{
+	bool ret = true;
+
+	ret &= ((mmio_read_32(MP_CPUSYS_TOP_MP_ADB_DCM_CFG0) &
+		MP_CPUSYS_TOP_ADB_DCM_REG0_MASK) ==
+		(unsigned int) MP_CPUSYS_TOP_ADB_DCM_REG0_ON);
+	ret &= ((mmio_read_32(MP_CPUSYS_TOP_MP_ADB_DCM_CFG4) &
+		MP_CPUSYS_TOP_ADB_DCM_REG1_MASK) ==
+		(unsigned int) MP_CPUSYS_TOP_ADB_DCM_REG1_ON);
+	ret &= ((mmio_read_32(MP_CPUSYS_TOP_MCUSYS_DCM_CFG0) &
+		MP_CPUSYS_TOP_ADB_DCM_REG2_MASK) ==
+		(unsigned int) MP_CPUSYS_TOP_ADB_DCM_REG2_ON);
+
+	return ret;
+}
+
+void dcm_mp_cpusys_top_adb_dcm(bool on)
+{
+	if (on) {
+		/* TINFO = "Turn ON DCM 'mp_cpusys_top_adb_dcm'" */
+		mmio_clrsetbits_32(MP_CPUSYS_TOP_MP_ADB_DCM_CFG0,
+			MP_CPUSYS_TOP_ADB_DCM_REG0_MASK,
+			MP_CPUSYS_TOP_ADB_DCM_REG0_ON);
+		mmio_clrsetbits_32(MP_CPUSYS_TOP_MP_ADB_DCM_CFG4,
+			MP_CPUSYS_TOP_ADB_DCM_REG1_MASK,
+			MP_CPUSYS_TOP_ADB_DCM_REG1_ON);
+		mmio_clrsetbits_32(MP_CPUSYS_TOP_MCUSYS_DCM_CFG0,
+			MP_CPUSYS_TOP_ADB_DCM_REG2_MASK,
+			MP_CPUSYS_TOP_ADB_DCM_REG2_ON);
+	} else {
+		/* TINFO = "Turn OFF DCM 'mp_cpusys_top_adb_dcm'" */
+		mmio_clrsetbits_32(MP_CPUSYS_TOP_MP_ADB_DCM_CFG0,
+			MP_CPUSYS_TOP_ADB_DCM_REG0_MASK,
+			MP_CPUSYS_TOP_ADB_DCM_REG0_OFF);
+		mmio_clrsetbits_32(MP_CPUSYS_TOP_MP_ADB_DCM_CFG4,
+			MP_CPUSYS_TOP_ADB_DCM_REG1_MASK,
+			MP_CPUSYS_TOP_ADB_DCM_REG1_OFF);
+		mmio_clrsetbits_32(MP_CPUSYS_TOP_MCUSYS_DCM_CFG0,
+			MP_CPUSYS_TOP_ADB_DCM_REG2_MASK,
+			MP_CPUSYS_TOP_ADB_DCM_REG2_OFF);
+	}
+}
+
+#define MP_CPUSYS_TOP_APB_DCM_REG0_MASK (BIT(5))
+#define MP_CPUSYS_TOP_APB_DCM_REG1_MASK (BIT(8))
+#define MP_CPUSYS_TOP_APB_DCM_REG2_MASK (BIT(16))
+#define MP_CPUSYS_TOP_APB_DCM_REG0_ON (BIT(5))
+#define MP_CPUSYS_TOP_APB_DCM_REG1_ON (BIT(8))
+#define MP_CPUSYS_TOP_APB_DCM_REG2_ON (BIT(16))
+#define MP_CPUSYS_TOP_APB_DCM_REG0_OFF ((0x0 << 5))
+#define MP_CPUSYS_TOP_APB_DCM_REG1_OFF ((0x0 << 8))
+#define MP_CPUSYS_TOP_APB_DCM_REG2_OFF ((0x0 << 16))
+
+bool dcm_mp_cpusys_top_apb_dcm_is_on(void)
+{
+	bool ret = true;
+
+	ret &= ((mmio_read_32(MP_CPUSYS_TOP_MP_MISC_DCM_CFG0) &
+		MP_CPUSYS_TOP_APB_DCM_REG0_MASK) ==
+		(unsigned int) MP_CPUSYS_TOP_APB_DCM_REG0_ON);
+	ret &= ((mmio_read_32(MP_CPUSYS_TOP_MCUSYS_DCM_CFG0) &
+		MP_CPUSYS_TOP_APB_DCM_REG1_MASK) ==
+		(unsigned int) MP_CPUSYS_TOP_APB_DCM_REG1_ON);
+	ret &= ((mmio_read_32(MP_CPUSYS_TOP_MP0_DCM_CFG0) &
+		MP_CPUSYS_TOP_APB_DCM_REG2_MASK) ==
+		(unsigned int) MP_CPUSYS_TOP_APB_DCM_REG2_ON);
+
+	return ret;
+}
+
+void dcm_mp_cpusys_top_apb_dcm(bool on)
+{
+	if (on) {
+		/* TINFO = "Turn ON DCM 'mp_cpusys_top_apb_dcm'" */
+		mmio_clrsetbits_32(MP_CPUSYS_TOP_MP_MISC_DCM_CFG0,
+			MP_CPUSYS_TOP_APB_DCM_REG0_MASK,
+			MP_CPUSYS_TOP_APB_DCM_REG0_ON);
+		mmio_clrsetbits_32(MP_CPUSYS_TOP_MCUSYS_DCM_CFG0,
+			MP_CPUSYS_TOP_APB_DCM_REG1_MASK,
+			MP_CPUSYS_TOP_APB_DCM_REG1_ON);
+		mmio_clrsetbits_32(MP_CPUSYS_TOP_MP0_DCM_CFG0,
+			MP_CPUSYS_TOP_APB_DCM_REG2_MASK,
+			MP_CPUSYS_TOP_APB_DCM_REG2_ON);
+	} else {
+		/* TINFO = "Turn OFF DCM 'mp_cpusys_top_apb_dcm'" */
+		mmio_clrsetbits_32(MP_CPUSYS_TOP_MP_MISC_DCM_CFG0,
+			MP_CPUSYS_TOP_APB_DCM_REG0_MASK,
+			MP_CPUSYS_TOP_APB_DCM_REG0_OFF);
+		mmio_clrsetbits_32(MP_CPUSYS_TOP_MCUSYS_DCM_CFG0,
+			MP_CPUSYS_TOP_APB_DCM_REG1_MASK,
+			MP_CPUSYS_TOP_APB_DCM_REG1_OFF);
+		mmio_clrsetbits_32(MP_CPUSYS_TOP_MP0_DCM_CFG0,
+			MP_CPUSYS_TOP_APB_DCM_REG2_MASK,
+			MP_CPUSYS_TOP_APB_DCM_REG2_OFF);
+	}
+}
+
+#define MP_CPUSYS_TOP_BUS_PLL_DIV_DCM_REG0_MASK (BIT(11) | \
+			BIT(24) | \
+			BIT(25))
+#define MP_CPUSYS_TOP_BUS_PLL_DIV_DCM_REG0_ON (BIT(11) | \
+			BIT(24) | \
+			BIT(25))
+#define MP_CPUSYS_TOP_BUS_PLL_DIV_DCM_REG0_OFF ((0x0 << 11) | \
+			(0x0 << 24) | \
+			(0x0 << 25))
+
+bool dcm_mp_cpusys_top_bus_pll_div_dcm_is_on(void)
+{
+	bool ret = true;
+
+	ret &= ((mmio_read_32(MP_CPUSYS_TOP_BUS_PLLDIV_CFG) &
+		MP_CPUSYS_TOP_BUS_PLL_DIV_DCM_REG0_MASK) ==
+		(unsigned int) MP_CPUSYS_TOP_BUS_PLL_DIV_DCM_REG0_ON);
+
+	return ret;
+}
+
+void dcm_mp_cpusys_top_bus_pll_div_dcm(bool on)
+{
+	if (on) {
+		/* TINFO = "Turn ON DCM 'mp_cpusys_top_bus_pll_div_dcm'" */
+		mmio_clrsetbits_32(MP_CPUSYS_TOP_BUS_PLLDIV_CFG,
+			MP_CPUSYS_TOP_BUS_PLL_DIV_DCM_REG0_MASK,
+			MP_CPUSYS_TOP_BUS_PLL_DIV_DCM_REG0_ON);
+	} else {
+		/* TINFO = "Turn OFF DCM 'mp_cpusys_top_bus_pll_div_dcm'" */
+		mmio_clrsetbits_32(MP_CPUSYS_TOP_BUS_PLLDIV_CFG,
+			MP_CPUSYS_TOP_BUS_PLL_DIV_DCM_REG0_MASK,
+			MP_CPUSYS_TOP_BUS_PLL_DIV_DCM_REG0_OFF);
+	}
+}
+
+#define MP_CPUSYS_TOP_CORE_STALL_DCM_REG0_MASK (BIT(0))
+#define MP_CPUSYS_TOP_CORE_STALL_DCM_REG0_ON (BIT(0))
+#define MP_CPUSYS_TOP_CORE_STALL_DCM_REG0_OFF ((0x0 << 0))
+
+bool dcm_mp_cpusys_top_core_stall_dcm_is_on(void)
+{
+	bool ret = true;
+
+	ret &= ((mmio_read_32(MP_CPUSYS_TOP_MP0_DCM_CFG7) &
+		MP_CPUSYS_TOP_CORE_STALL_DCM_REG0_MASK) ==
+		(unsigned int) MP_CPUSYS_TOP_CORE_STALL_DCM_REG0_ON);
+
+	return ret;
+}
+
+void dcm_mp_cpusys_top_core_stall_dcm(bool on)
+{
+	if (on) {
+		/* TINFO = "Turn ON DCM 'mp_cpusys_top_core_stall_dcm'" */
+		mmio_clrsetbits_32(MP_CPUSYS_TOP_MP0_DCM_CFG7,
+			MP_CPUSYS_TOP_CORE_STALL_DCM_REG0_MASK,
+			MP_CPUSYS_TOP_CORE_STALL_DCM_REG0_ON);
+	} else {
+		/* TINFO = "Turn OFF DCM 'mp_cpusys_top_core_stall_dcm'" */
+		mmio_clrsetbits_32(MP_CPUSYS_TOP_MP0_DCM_CFG7,
+			MP_CPUSYS_TOP_CORE_STALL_DCM_REG0_MASK,
+			MP_CPUSYS_TOP_CORE_STALL_DCM_REG0_OFF);
+	}
+}
+
+#define MP_CPUSYS_TOP_CPUBIU_DCM_REG0_MASK ((0xffff << 0))
+#define MP_CPUSYS_TOP_CPUBIU_DCM_REG0_ON ((0xffff << 0))
+#define MP_CPUSYS_TOP_CPUBIU_DCM_REG0_OFF ((0x0 << 0))
+
+bool dcm_mp_cpusys_top_cpubiu_dcm_is_on(void)
+{
+	bool ret = true;
+
+	ret &= ((mmio_read_32(MP_CPUSYS_TOP_MCSIC_DCM0) &
+		MP_CPUSYS_TOP_CPUBIU_DCM_REG0_MASK) ==
+		(unsigned int) MP_CPUSYS_TOP_CPUBIU_DCM_REG0_ON);
+
+	return ret;
+}
+
+void dcm_mp_cpusys_top_cpubiu_dcm(bool on)
+{
+	if (on) {
+		/* TINFO = "Turn ON DCM 'mp_cpusys_top_cpubiu_dcm'" */
+		mmio_clrsetbits_32(MP_CPUSYS_TOP_MCSIC_DCM0,
+			MP_CPUSYS_TOP_CPUBIU_DCM_REG0_MASK,
+			MP_CPUSYS_TOP_CPUBIU_DCM_REG0_ON);
+	} else {
+		/* TINFO = "Turn OFF DCM 'mp_cpusys_top_cpubiu_dcm'" */
+		mmio_clrsetbits_32(MP_CPUSYS_TOP_MCSIC_DCM0,
+			MP_CPUSYS_TOP_CPUBIU_DCM_REG0_MASK,
+			MP_CPUSYS_TOP_CPUBIU_DCM_REG0_OFF);
+	}
+}
+
+#define MP_CPUSYS_TOP_CPU_PLL_DIV_0_DCM_REG0_MASK (BIT(24) | \
+			BIT(25))
+#define MP_CPUSYS_TOP_CPU_PLL_DIV_0_DCM_REG0_ON (BIT(24) | \
+			BIT(25))
+#define MP_CPUSYS_TOP_CPU_PLL_DIV_0_DCM_REG0_OFF ((0x0 << 24) | \
+			(0x0 << 25))
+
+bool dcm_mp_cpusys_top_cpu_pll_div_0_dcm_is_on(void)
+{
+	bool ret = true;
+
+	ret &= ((mmio_read_32(MP_CPUSYS_TOP_CPU_PLLDIV_CFG0) &
+		MP_CPUSYS_TOP_CPU_PLL_DIV_0_DCM_REG0_MASK) ==
+		(unsigned int) MP_CPUSYS_TOP_CPU_PLL_DIV_0_DCM_REG0_ON);
+
+	return ret;
+}
+
+void dcm_mp_cpusys_top_cpu_pll_div_0_dcm(bool on)
+{
+	if (on) {
+		/* TINFO = "Turn ON DCM 'mp_cpusys_top_cpu_pll_div_0_dcm'" */
+		mmio_clrsetbits_32(MP_CPUSYS_TOP_CPU_PLLDIV_CFG0,
+			MP_CPUSYS_TOP_CPU_PLL_DIV_0_DCM_REG0_MASK,
+			MP_CPUSYS_TOP_CPU_PLL_DIV_0_DCM_REG0_ON);
+	} else {
+		/* TINFO = "Turn OFF DCM 'mp_cpusys_top_cpu_pll_div_0_dcm'" */
+		mmio_clrsetbits_32(MP_CPUSYS_TOP_CPU_PLLDIV_CFG0,
+			MP_CPUSYS_TOP_CPU_PLL_DIV_0_DCM_REG0_MASK,
+			MP_CPUSYS_TOP_CPU_PLL_DIV_0_DCM_REG0_OFF);
+	}
+}
+
+#define MP_CPUSYS_TOP_CPU_PLL_DIV_1_DCM_REG0_MASK (BIT(24) | \
+			BIT(25))
+#define MP_CPUSYS_TOP_CPU_PLL_DIV_1_DCM_REG0_ON (BIT(24) | \
+			BIT(25))
+#define MP_CPUSYS_TOP_CPU_PLL_DIV_1_DCM_REG0_OFF ((0x0 << 24) | \
+			(0x0 << 25))
+
+bool dcm_mp_cpusys_top_cpu_pll_div_1_dcm_is_on(void)
+{
+	bool ret = true;
+
+	ret &= ((mmio_read_32(MP_CPUSYS_TOP_CPU_PLLDIV_CFG1) &
+		MP_CPUSYS_TOP_CPU_PLL_DIV_1_DCM_REG0_MASK) ==
+		(unsigned int) MP_CPUSYS_TOP_CPU_PLL_DIV_1_DCM_REG0_ON);
+
+	return ret;
+}
+
+void dcm_mp_cpusys_top_cpu_pll_div_1_dcm(bool on)
+{
+	if (on) {
+		/* TINFO = "Turn ON DCM 'mp_cpusys_top_cpu_pll_div_1_dcm'" */
+		mmio_clrsetbits_32(MP_CPUSYS_TOP_CPU_PLLDIV_CFG1,
+			MP_CPUSYS_TOP_CPU_PLL_DIV_1_DCM_REG0_MASK,
+			MP_CPUSYS_TOP_CPU_PLL_DIV_1_DCM_REG0_ON);
+	} else {
+		/* TINFO = "Turn OFF DCM 'mp_cpusys_top_cpu_pll_div_1_dcm'" */
+		mmio_clrsetbits_32(MP_CPUSYS_TOP_CPU_PLLDIV_CFG1,
+			MP_CPUSYS_TOP_CPU_PLL_DIV_1_DCM_REG0_MASK,
+			MP_CPUSYS_TOP_CPU_PLL_DIV_1_DCM_REG0_OFF);
+	}
+}
+
+#define MP_CPUSYS_TOP_FCM_STALL_DCM_REG0_MASK (BIT(4))
+#define MP_CPUSYS_TOP_FCM_STALL_DCM_REG0_ON (BIT(4))
+#define MP_CPUSYS_TOP_FCM_STALL_DCM_REG0_OFF ((0x0 << 4))
+
+bool dcm_mp_cpusys_top_fcm_stall_dcm_is_on(void)
+{
+	bool ret = true;
+
+	ret &= ((mmio_read_32(MP_CPUSYS_TOP_MP0_DCM_CFG7) &
+		MP_CPUSYS_TOP_FCM_STALL_DCM_REG0_MASK) ==
+		(unsigned int) MP_CPUSYS_TOP_FCM_STALL_DCM_REG0_ON);
+
+	return ret;
+}
+
+void dcm_mp_cpusys_top_fcm_stall_dcm(bool on)
+{
+	if (on) {
+		/* TINFO = "Turn ON DCM 'mp_cpusys_top_fcm_stall_dcm'" */
+		mmio_clrsetbits_32(MP_CPUSYS_TOP_MP0_DCM_CFG7,
+			MP_CPUSYS_TOP_FCM_STALL_DCM_REG0_MASK,
+			MP_CPUSYS_TOP_FCM_STALL_DCM_REG0_ON);
+	} else {
+		/* TINFO = "Turn OFF DCM 'mp_cpusys_top_fcm_stall_dcm'" */
+		mmio_clrsetbits_32(MP_CPUSYS_TOP_MP0_DCM_CFG7,
+			MP_CPUSYS_TOP_FCM_STALL_DCM_REG0_MASK,
+			MP_CPUSYS_TOP_FCM_STALL_DCM_REG0_OFF);
+	}
+}
+
+#define MP_CPUSYS_TOP_LAST_COR_IDLE_DCM_REG0_MASK ((0x1U << 31))
+#define MP_CPUSYS_TOP_LAST_COR_IDLE_DCM_REG0_ON ((0x1U << 31))
+#define MP_CPUSYS_TOP_LAST_COR_IDLE_DCM_REG0_OFF ((0x0U << 31))
+
+bool dcm_mp_cpusys_top_last_cor_idle_dcm_is_on(void)
+{
+	bool ret = true;
+
+	ret &= ((mmio_read_32(MP_CPUSYS_TOP_BUS_PLLDIV_CFG) &
+		MP_CPUSYS_TOP_LAST_COR_IDLE_DCM_REG0_MASK) ==
+		(unsigned int) MP_CPUSYS_TOP_LAST_COR_IDLE_DCM_REG0_ON);
+
+	return ret;
+}
+
+void dcm_mp_cpusys_top_last_cor_idle_dcm(bool on)
+{
+	if (on) {
+		/* TINFO = "Turn ON DCM 'mp_cpusys_top_last_cor_idle_dcm'" */
+		mmio_clrsetbits_32(MP_CPUSYS_TOP_BUS_PLLDIV_CFG,
+			MP_CPUSYS_TOP_LAST_COR_IDLE_DCM_REG0_MASK,
+			MP_CPUSYS_TOP_LAST_COR_IDLE_DCM_REG0_ON);
+	} else {
+		/* TINFO = "Turn OFF DCM 'mp_cpusys_top_last_cor_idle_dcm'" */
+		mmio_clrsetbits_32(MP_CPUSYS_TOP_BUS_PLLDIV_CFG,
+			MP_CPUSYS_TOP_LAST_COR_IDLE_DCM_REG0_MASK,
+			MP_CPUSYS_TOP_LAST_COR_IDLE_DCM_REG0_OFF);
+	}
+}
+
+#define MP_CPUSYS_TOP_MISC_DCM_REG0_MASK (BIT(1) | \
+			BIT(4))
+#define MP_CPUSYS_TOP_MISC_DCM_REG0_ON (BIT(1) | \
+			BIT(4))
+#define MP_CPUSYS_TOP_MISC_DCM_REG0_OFF ((0x0 << 1) | \
+			(0x0 << 4))
+
+bool dcm_mp_cpusys_top_misc_dcm_is_on(void)
+{
+	bool ret = true;
+
+	ret &= ((mmio_read_32(MP_CPUSYS_TOP_MP_MISC_DCM_CFG0) &
+		MP_CPUSYS_TOP_MISC_DCM_REG0_MASK) ==
+		(unsigned int) MP_CPUSYS_TOP_MISC_DCM_REG0_ON);
+
+	return ret;
+}
+
+void dcm_mp_cpusys_top_misc_dcm(bool on)
+{
+	if (on) {
+		/* TINFO = "Turn ON DCM 'mp_cpusys_top_misc_dcm'" */
+		mmio_clrsetbits_32(MP_CPUSYS_TOP_MP_MISC_DCM_CFG0,
+			MP_CPUSYS_TOP_MISC_DCM_REG0_MASK,
+			MP_CPUSYS_TOP_MISC_DCM_REG0_ON);
+	} else {
+		/* TINFO = "Turn OFF DCM 'mp_cpusys_top_misc_dcm'" */
+		mmio_clrsetbits_32(MP_CPUSYS_TOP_MP_MISC_DCM_CFG0,
+			MP_CPUSYS_TOP_MISC_DCM_REG0_MASK,
+			MP_CPUSYS_TOP_MISC_DCM_REG0_OFF);
+	}
+}
+
+#define MP_CPUSYS_TOP_MP0_QDCM_REG0_MASK (BIT(3))
+#define MP_CPUSYS_TOP_MP0_QDCM_REG1_MASK (BIT(0) | \
+			BIT(1) | \
+			BIT(2) | \
+			BIT(3))
+#define MP_CPUSYS_TOP_MP0_QDCM_REG0_ON (BIT(3))
+#define MP_CPUSYS_TOP_MP0_QDCM_REG1_ON (BIT(0) | \
+			BIT(1) | \
+			BIT(2) | \
+			BIT(3))
+#define MP_CPUSYS_TOP_MP0_QDCM_REG0_OFF ((0x0 << 3))
+#define MP_CPUSYS_TOP_MP0_QDCM_REG1_OFF ((0x0 << 0) | \
+			(0x0 << 1) | \
+			(0x0 << 2) | \
+			(0x0 << 3))
+
+bool dcm_mp_cpusys_top_mp0_qdcm_is_on(void)
+{
+	bool ret = true;
+
+	ret &= ((mmio_read_32(MP_CPUSYS_TOP_MP_MISC_DCM_CFG0) &
+		MP_CPUSYS_TOP_MP0_QDCM_REG0_MASK) ==
+		(unsigned int) MP_CPUSYS_TOP_MP0_QDCM_REG0_ON);
+	ret &= ((mmio_read_32(MP_CPUSYS_TOP_MP0_DCM_CFG0) &
+		MP_CPUSYS_TOP_MP0_QDCM_REG1_MASK) ==
+		(unsigned int) MP_CPUSYS_TOP_MP0_QDCM_REG1_ON);
+
+	return ret;
+}
+
+void dcm_mp_cpusys_top_mp0_qdcm(bool on)
+{
+	if (on) {
+		/* TINFO = "Turn ON DCM 'mp_cpusys_top_mp0_qdcm'" */
+		mmio_clrsetbits_32(MP_CPUSYS_TOP_MP_MISC_DCM_CFG0,
+			MP_CPUSYS_TOP_MP0_QDCM_REG0_MASK,
+			MP_CPUSYS_TOP_MP0_QDCM_REG0_ON);
+		mmio_clrsetbits_32(MP_CPUSYS_TOP_MP0_DCM_CFG0,
+			MP_CPUSYS_TOP_MP0_QDCM_REG1_MASK,
+			MP_CPUSYS_TOP_MP0_QDCM_REG1_ON);
+	} else {
+		/* TINFO = "Turn OFF DCM 'mp_cpusys_top_mp0_qdcm'" */
+		mmio_clrsetbits_32(MP_CPUSYS_TOP_MP_MISC_DCM_CFG0,
+			MP_CPUSYS_TOP_MP0_QDCM_REG0_MASK,
+			MP_CPUSYS_TOP_MP0_QDCM_REG0_OFF);
+		mmio_clrsetbits_32(MP_CPUSYS_TOP_MP0_DCM_CFG0,
+			MP_CPUSYS_TOP_MP0_QDCM_REG1_MASK,
+			MP_CPUSYS_TOP_MP0_QDCM_REG1_OFF);
+	}
+}
+
+#define CPCCFG_REG_EMI_WFIFO_REG0_MASK (BIT(0) | \
+			BIT(1) | \
+			BIT(2) | \
+			BIT(3))
+#define CPCCFG_REG_EMI_WFIFO_REG0_ON (BIT(0) | \
+			BIT(1) | \
+			BIT(2) | \
+			BIT(3))
+#define CPCCFG_REG_EMI_WFIFO_REG0_OFF ((0x0 << 0) | \
+			(0x0 << 1) | \
+			(0x0 << 2) | \
+			(0x0 << 3))
+
+bool dcm_cpccfg_reg_emi_wfifo_is_on(void)
+{
+	bool ret = true;
+
+	ret &= ((mmio_read_32(CPCCFG_REG_EMI_WFIFO) &
+		CPCCFG_REG_EMI_WFIFO_REG0_MASK) ==
+		(unsigned int) CPCCFG_REG_EMI_WFIFO_REG0_ON);
+
+	return ret;
+}
+
+void dcm_cpccfg_reg_emi_wfifo(bool on)
+{
+	if (on) {
+		/* TINFO = "Turn ON DCM 'cpccfg_reg_emi_wfifo'" */
+		mmio_clrsetbits_32(CPCCFG_REG_EMI_WFIFO,
+			CPCCFG_REG_EMI_WFIFO_REG0_MASK,
+			CPCCFG_REG_EMI_WFIFO_REG0_ON);
+	} else {
+		/* TINFO = "Turn OFF DCM 'cpccfg_reg_emi_wfifo'" */
+		mmio_clrsetbits_32(CPCCFG_REG_EMI_WFIFO,
+			CPCCFG_REG_EMI_WFIFO_REG0_MASK,
+			CPCCFG_REG_EMI_WFIFO_REG0_OFF);
+	}
+}
diff --git a/plat/mediatek/mt8195/drivers/dcm/mtk_dcm_utils.h b/plat/mediatek/mt8195/drivers/dcm/mtk_dcm_utils.h
new file mode 100644
index 0000000..e5743af
--- /dev/null
+++ b/plat/mediatek/mt8195/drivers/dcm/mtk_dcm_utils.h
@@ -0,0 +1,59 @@
+/*
+ * Copyright (c) 2021, MediaTek Inc. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef MTK_DCM_UTILS_H
+#define MTK_DCM_UTILS_H
+
+#include <stdbool.h>
+
+#include <mtk_dcm.h>
+#include <platform_def.h>
+
+/* Base */
+#define MP_CPUSYS_TOP_BASE	(MCUCFG_BASE + 0x8000)
+#define CPCCFG_REG_BASE		(MCUCFG_BASE + 0xA800)
+
+/* Register Definition */
+#define MP_CPUSYS_TOP_CPU_PLLDIV_CFG0 (MP_CPUSYS_TOP_BASE + 0x22a0)
+#define MP_CPUSYS_TOP_CPU_PLLDIV_CFG1 (MP_CPUSYS_TOP_BASE + 0x22a4)
+#define MP_CPUSYS_TOP_BUS_PLLDIV_CFG (MP_CPUSYS_TOP_BASE + 0x22e0)
+#define MP_CPUSYS_TOP_MCSIC_DCM0 (MP_CPUSYS_TOP_BASE + 0x2440)
+#define MP_CPUSYS_TOP_MP_ADB_DCM_CFG0 (MP_CPUSYS_TOP_BASE + 0x2500)
+#define MP_CPUSYS_TOP_MP_ADB_DCM_CFG4 (MP_CPUSYS_TOP_BASE + 0x2510)
+#define MP_CPUSYS_TOP_MP_MISC_DCM_CFG0 (MP_CPUSYS_TOP_BASE + 0x2518)
+#define MP_CPUSYS_TOP_MCUSYS_DCM_CFG0 (MP_CPUSYS_TOP_BASE + 0x25c0)
+#define CPCCFG_REG_EMI_WFIFO (CPCCFG_REG_BASE + 0x100)
+#define MP_CPUSYS_TOP_MP0_DCM_CFG0 (MP_CPUSYS_TOP_BASE + 0x4880)
+#define MP_CPUSYS_TOP_MP0_DCM_CFG7 (MP_CPUSYS_TOP_BASE + 0x489c)
+
+/* MP_CPUSYS_TOP */
+bool dcm_mp_cpusys_top_adb_dcm_is_on(void);
+void dcm_mp_cpusys_top_adb_dcm(bool on);
+bool dcm_mp_cpusys_top_apb_dcm_is_on(void);
+void dcm_mp_cpusys_top_apb_dcm(bool on);
+bool dcm_mp_cpusys_top_bus_pll_div_dcm_is_on(void);
+void dcm_mp_cpusys_top_bus_pll_div_dcm(bool on);
+bool dcm_mp_cpusys_top_core_stall_dcm_is_on(void);
+void dcm_mp_cpusys_top_core_stall_dcm(bool on);
+bool dcm_mp_cpusys_top_cpubiu_dcm_is_on(void);
+void dcm_mp_cpusys_top_cpubiu_dcm(bool on);
+bool dcm_mp_cpusys_top_cpu_pll_div_0_dcm_is_on(void);
+void dcm_mp_cpusys_top_cpu_pll_div_0_dcm(bool on);
+bool dcm_mp_cpusys_top_cpu_pll_div_1_dcm_is_on(void);
+void dcm_mp_cpusys_top_cpu_pll_div_1_dcm(bool on);
+bool dcm_mp_cpusys_top_fcm_stall_dcm_is_on(void);
+void dcm_mp_cpusys_top_fcm_stall_dcm(bool on);
+bool dcm_mp_cpusys_top_last_cor_idle_dcm_is_on(void);
+void dcm_mp_cpusys_top_last_cor_idle_dcm(bool on);
+bool dcm_mp_cpusys_top_misc_dcm_is_on(void);
+void dcm_mp_cpusys_top_misc_dcm(bool on);
+bool dcm_mp_cpusys_top_mp0_qdcm_is_on(void);
+void dcm_mp_cpusys_top_mp0_qdcm(bool on);
+/* CPCCFG_REG */
+bool dcm_cpccfg_reg_emi_wfifo_is_on(void);
+void dcm_cpccfg_reg_emi_wfifo(bool on);
+
+#endif
diff --git a/plat/mediatek/mt8195/drivers/spm/mt_spm_suspend.c b/plat/mediatek/mt8195/drivers/spm/mt_spm_suspend.c
index b40fa87..4487348 100644
--- a/plat/mediatek/mt8195/drivers/spm/mt_spm_suspend.c
+++ b/plat/mediatek/mt8195/drivers/spm/mt_spm_suspend.c
@@ -97,7 +97,7 @@
 	/* [4] */
 	.reg_spm_vrf18_req = 0,
 	/* [7] FIXME: default disable HW Auto S1*/
-	.reg_spm_ddr_en_req = 1,
+	.reg_spm_ddr_en_req = 0,
 	/* [8] */
 	.reg_spm_dvfs_req = 0,
 	/* [9] */
diff --git a/plat/mediatek/mt8195/platform.mk b/plat/mediatek/mt8195/platform.mk
index 481e9ad..f4604c4 100644
--- a/plat/mediatek/mt8195/platform.mk
+++ b/plat/mediatek/mt8195/platform.mk
@@ -14,7 +14,8 @@
                  -I${MTK_PLAT}/common/drivers/timer/              \
                  -I${MTK_PLAT}/common/drivers/uart/               \
                  -I${MTK_PLAT}/common/lpm/                        \
-                 -I${MTK_PLAT_SOC}/drivers/dp/                  \
+                 -I${MTK_PLAT_SOC}/drivers/dcm                    \
+                 -I${MTK_PLAT_SOC}/drivers/dp/                    \
                  -I${MTK_PLAT_SOC}/drivers/gpio/                  \
                  -I${MTK_PLAT_SOC}/drivers/mcdi/                  \
                  -I${MTK_PLAT_SOC}/drivers/pmic/                  \
@@ -56,6 +57,8 @@
                 ${MTK_PLAT_SOC}/aarch64/platform_common.c             \
                 ${MTK_PLAT_SOC}/aarch64/plat_helpers.S                \
                 ${MTK_PLAT_SOC}/bl31_plat_setup.c                     \
+                ${MTK_PLAT_SOC}/drivers/dcm/mtk_dcm.c                 \
+                ${MTK_PLAT_SOC}/drivers/dcm/mtk_dcm_utils.c           \
                 ${MTK_PLAT_SOC}/drivers/dp/mt_dp.c                    \
                 ${MTK_PLAT_SOC}/drivers/gpio/mtgpio.c                 \
                 ${MTK_PLAT_SOC}/drivers/mcdi/mt_cpu_pm.c              \