diff --git a/plat/mediatek/mt8186/drivers/spmc/mtspmc_private.h b/plat/mediatek/mt8186/drivers/spmc/mtspmc_private.h
new file mode 100644
index 0000000..472b54c
--- /dev/null
+++ b/plat/mediatek/mt8186/drivers/spmc/mtspmc_private.h
@@ -0,0 +1,176 @@
+/*
+ * Copyright (c) 2021, MediaTek Inc. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef MTSPMC_PRIVATE_H
+#define MTSPMC_PRIVATE_H
+
+#include <lib/utils_def.h>
+#include <platform_def.h>
+
+unsigned long read_cpuectlr(void);
+void write_cpuectlr(unsigned long cpuectlr);
+
+unsigned long read_cpupwrctlr_el1(void);
+void write_cpupwrctlr_el1(unsigned long cpuectlr);
+
+/* per_cpu/cluster helper */
+struct per_cpu_reg {
+	unsigned int cluster_addr;
+	unsigned int cpu_stride;
+};
+
+#define per_cpu(cluster, cpu, reg)	\
+	(reg[cluster].cluster_addr + (cpu << reg[cluster].cpu_stride))
+
+#define per_cluster(cluster, reg)	(reg[cluster].cluster_addr)
+
+#define SPM_REG(ofs)			(uint32_t)(SPM_BASE + (ofs))
+#define MCUCFG_REG(ofs)			(uint32_t)(MCUCFG_BASE + (ofs))
+#define INFRACFG_AO_REG(ofs)		(uint32_t)(INFRACFG_AO_BASE + (ofs))
+
+/* SPMC related registers */
+#define SPM_POWERON_CONFIG_EN		SPM_REG(0x000)
+/* bit-fields of SPM_POWERON_CONFIG_EN */
+#define PROJECT_CODE			(U(0xb16) << 16)
+#define BCLK_CG_EN			BIT(0)
+
+#define SPM_PWR_STATUS			SPM_REG(0x16c)
+#define SPM_PWR_STATUS_2ND		SPM_REG(0x170)
+#define SPM_CPU_PWR_STATUS		SPM_REG(0x174)
+
+/* bit-fields of SPM_PWR_STATUS */
+#define MD				BIT(0)
+#define CONN				BIT(1)
+#define DDRPHY				BIT(2)
+#define DISP				BIT(3)
+#define MFG				BIT(4)
+#define ISP				BIT(5)
+#define INFRA				BIT(6)
+#define VDEC				BIT(7)
+#define MP0_CPUTOP			BIT(8)
+#define MP0_CPU0			BIT(9)
+#define MP0_CPU1			BIT(10)
+#define MP0_CPU2			BIT(11)
+#define MP0_CPU3			BIT(12)
+#define MCUSYS				BIT(14)
+#define MP0_CPU4			BIT(15)
+#define MP0_CPU5			BIT(16)
+#define MP0_CPU6			BIT(17)
+#define MP0_CPU7			BIT(18)
+#define VEN				BIT(21)
+
+/* SPMC related registers */
+#define SPM_MCUSYS_PWR_CON		SPM_REG(0x200)
+#define SPM_MP0_CPUTOP_PWR_CON		SPM_REG(0x204)
+#define SPM_MP0_CPU0_PWR_CON		SPM_REG(0x208)
+#define SPM_MP0_CPU1_PWR_CON		SPM_REG(0x20c)
+#define SPM_MP0_CPU2_PWR_CON		SPM_REG(0x210)
+#define SPM_MP0_CPU3_PWR_CON		SPM_REG(0x214)
+#define SPM_MP0_CPU4_PWR_CON		SPM_REG(0x218)
+#define SPM_MP0_CPU5_PWR_CON		SPM_REG(0x21c)
+#define SPM_MP0_CPU6_PWR_CON		SPM_REG(0x220)
+#define SPM_MP0_CPU7_PWR_CON		SPM_REG(0x224)
+
+/* bit-fields of SPM_*_PWR_CON */
+#define PWR_ON_ACK			BIT(31)
+#define VPROC_EXT_OFF			BIT(7)
+#define DORMANT_EN			BIT(6)
+#define RESETPWRON_CONFIG		BIT(5)
+#define PWR_CLK_DIS			BIT(4)
+#define PWR_ON				BIT(2)
+#define PWR_RST_B			BIT(0)
+
+/* per_cpu registers for SPM_MP0_CPU_PWR_CON */
+static const struct per_cpu_reg SPM_CPU_PWR[] = {
+	{ .cluster_addr = SPM_MP0_CPU0_PWR_CON, .cpu_stride = 2U }
+};
+
+/* per_cluster registers for SPM_MP0_CPUTOP_PWR_CON */
+static const struct per_cpu_reg SPM_CLUSTER_PWR[] = {
+	{ .cluster_addr = SPM_MP0_CPUTOP_PWR_CON, .cpu_stride = 0U }
+};
+
+/* MCUCFG related registers */
+#define MCUCFG_MP0_CLUSTER_CFG5		MCUCFG_REG(0xc8e4)
+/* reset vectors */
+#define MCUCFG_MP0_CLUSTER_CFG8		MCUCFG_REG(0xc900)
+#define MCUCFG_MP0_CLUSTER_CFG10	MCUCFG_REG(0xc908)
+#define MCUCFG_MP0_CLUSTER_CFG12	MCUCFG_REG(0xc910)
+#define MCUCFG_MP0_CLUSTER_CFG14	MCUCFG_REG(0xc918)
+#define MCUCFG_MP0_CLUSTER_CFG16	MCUCFG_REG(0xc920)
+#define MCUCFG_MP0_CLUSTER_CFG18	MCUCFG_REG(0xc928)
+#define MCUCFG_MP0_CLUSTER_CFG20	MCUCFG_REG(0xc930)
+#define MCUCFG_MP0_CLUSTER_CFG22	MCUCFG_REG(0xc938)
+
+/* per_cpu registers for MCUCFG_MP0_CLUSTER_CFG */
+static const struct per_cpu_reg MCUCFG_BOOTADDR[] = {
+	{ .cluster_addr = MCUCFG_MP0_CLUSTER_CFG8, .cpu_stride = 3U }
+};
+
+/* per_cpu registers for MCUCFG_MP0_CLUSTER_CFG5 */
+static const struct per_cpu_reg MCUCFG_INITARCH[] = {
+	{ .cluster_addr = MCUCFG_MP0_CLUSTER_CFG5, .cpu_stride = 0U }
+};
+
+#define MCUCFG_INITARCH_CPU_BIT(cpu)	BIT(16U + cpu)
+/* CPC control */
+#define MCUCFG_CPC_FLOW_CTRL_CFG	MCUCFG_REG(0xa814)
+#define MCUCFG_CPC_SPMC_PWR_STATUS	MCUCFG_REG(0xa840)
+
+/* bit-fields of CPC_FLOW_CTRL_CFG */
+#define CPC_CTRL_ENABLE			BIT(16)
+#define SSPM_ALL_PWR_CTRL_EN		BIT(13) /* for cpu-hotplug */
+#define GIC_WAKEUP_IGNORE(cpu)		BIT(21 + cpu)
+
+/* bit-fields of CPC_SPMC_PWR_STATUS */
+#define CORE_SPMC_PWR_ON_ACK		GENMASK(11, 0)
+
+/* APB module infracfg_ao */
+#define INFRA_TOPAXI_PROTECTEN		INFRACFG_AO_REG(0x0220)
+#define INFRA_TOPAXI_PROTECTEN_STA0	INFRACFG_AO_REG(0x0224)
+#define INFRA_TOPAXI_PROTECTEN_STA1	INFRACFG_AO_REG(0x0228)
+#define INFRA_TOPAXI_PROTECTEN_SET	INFRACFG_AO_REG(0x02a0)
+#define INFRA_TOPAXI_PROTECTEN_CLR	INFRACFG_AO_REG(0x02a4)
+#define INFRA_TOPAXI_PROTECTEN_1	INFRACFG_AO_REG(0x0250)
+#define INFRA_TOPAXI_PROTECTEN_STA0_1	INFRACFG_AO_REG(0x0254)
+#define INFRA_TOPAXI_PROTECTEN_STA1_1	INFRACFG_AO_REG(0x0258)
+#define INFRA_TOPAXI_PROTECTEN_1_SET	INFRACFG_AO_REG(0x02a8)
+#define INFRA_TOPAXI_PROTECTEN_1_CLR	INFRACFG_AO_REG(0x02ac)
+
+/* bit-fields of INFRA_TOPAXI_PROTECTEN */
+#define MP0_SPMC_PROT_STEP1_0_MASK	BIT(12)
+#define MP0_SPMC_PROT_STEP1_1_MASK	(BIT(26) | BIT(12))
+
+/* SPARK */
+#define VOLTAGE_04			U(0x40)
+#define VOLTAGE_05			U(0x60)
+
+#define PTP3_CPU0_SPMC_SW_CFG		MCUCFG_REG(0x200)
+#define CPU0_ILDO_CONTROL5		MCUCFG_REG(0x334)
+#define CPU0_ILDO_CONTROL8		MCUCFG_REG(0x340)
+
+/* bit-fields of CPU0_ILDO_CONTROL5 */
+#define ILDO_RET_VOSEL			GENMASK(7, 0)
+
+/* bit-fields of PTP3_CPU_SPMC_SW_CFG */
+#define SW_SPARK_EN			BIT(0)
+
+/* bit-fields of CPU0_ILDO_CONTROL8 */
+#define ILDO_BYPASS_B			BIT(0)
+
+static const struct per_cpu_reg MCUCFG_SPARK[] = {
+	{ .cluster_addr = PTP3_CPU0_SPMC_SW_CFG, .cpu_stride = 11U }
+};
+
+static const struct per_cpu_reg ILDO_CONTROL5[] = {
+	{ .cluster_addr = CPU0_ILDO_CONTROL5, .cpu_stride = 11U }
+};
+
+static const struct per_cpu_reg ILDO_CONTROL8[] = {
+	{ .cluster_addr = CPU0_ILDO_CONTROL8, .cpu_stride = 11U }
+};
+
+#endif /* MTSPMC_PRIVATE_H */