diff --git a/plat/mediatek/mt8183/drivers/mcsi/mcsi.c b/plat/mediatek/mt8183/drivers/mcsi/mcsi.c
new file mode 100644
index 0000000..cbe7f0a
--- /dev/null
+++ b/plat/mediatek/mt8183/drivers/mcsi/mcsi.c
@@ -0,0 +1,211 @@
+/*
+ * Copyright (c) 2019, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <arch.h>
+#include <arch_helpers.h>
+#include <assert.h>
+#include <common/debug.h>
+#include <lib/mmio.h>
+#include <scu.h>
+#include <mcucfg.h>
+#include <drivers/delay_timer.h>
+#include <mcsi/mcsi.h>
+
+#define MAX_CLUSTERS		5
+
+static unsigned long cci_base_addr;
+static unsigned int cci_cluster_ix_to_iface[MAX_CLUSTERS];
+
+void mcsi_init(unsigned long cci_base,
+		unsigned int num_cci_masters)
+{
+	int i;
+
+	assert(cci_base);
+	assert(num_cci_masters < MAX_CLUSTERS);
+
+	cci_base_addr = cci_base;
+
+	for (i = 0; i < num_cci_masters; i++)
+		cci_cluster_ix_to_iface[i] = SLAVE_IFACE_OFFSET(i);
+}
+
+void mcsi_cache_flush(void)
+{
+	/* timeout is 10ms */
+	int timeout = 10000;
+
+	/* to make flush by SF safe, need to disable BIU DCM */
+	mmio_clrbits_32(CCI_CLK_CTRL, 1 << 8);
+	mmio_write_32(cci_base_addr + FLUSH_SF, 0x1);
+
+	for (; timeout; timeout--, udelay(1)) {
+		if ((mmio_read_32(cci_base_addr + FLUSH_SF) & 0x1) == 0x0)
+			break;
+	}
+
+	if (!timeout) {
+		INFO("SF lush timeout\n");
+		return;
+	}
+
+	/* enable BIU DCM as it was */
+	mmio_setbits_32(CCI_CLK_CTRL, 1 << 8);
+}
+
+static inline unsigned long get_slave_iface_base(unsigned long mpidr)
+{
+	/*
+	 * We assume the TF topology code allocates affinity instances
+	 * consecutively from zero.
+	 * It is a programming error if this is called without initializing
+	 * the slave interface to use for this cluster.
+	 */
+	unsigned int cluster_id =
+		(mpidr >> MPIDR_AFF1_SHIFT) & MPIDR_AFFLVL_MASK;
+
+	assert(cluster_id < MAX_CLUSTERS);
+	assert(cci_cluster_ix_to_iface[cluster_id] != 0);
+
+	return cci_base_addr + cci_cluster_ix_to_iface[cluster_id];
+}
+
+void cci_enable_cluster_coherency(unsigned long mpidr)
+{
+	unsigned long slave_base;
+	unsigned int support_ability;
+	unsigned int config = 0;
+	unsigned int pending = 0;
+
+	assert(cci_base_addr);
+	slave_base  = get_slave_iface_base(mpidr);
+	support_ability = mmio_read_32(slave_base);
+
+	pending = (mmio_read_32(
+		   cci_base_addr + SNP_PENDING_REG)) >> SNP_PENDING;
+	while (pending) {
+		pending = (mmio_read_32(
+			   cci_base_addr + SNP_PENDING_REG)) >> SNP_PENDING;
+	}
+
+	if (support_ability & SNP_SUPPORT)
+		config |= SNOOP_EN_BIT;
+	if (support_ability & DVM_SUPPORT)
+		config |= DVM_EN_BIT;
+
+	mmio_write_32(slave_base, support_ability | config);
+
+	/* Wait for the dust to settle down */
+	while (mmio_read_32(cci_base_addr + SNP_PENDING_REG) >> SNP_PENDING)
+		;
+}
+
+#if ERRATA_MCSIB_SW
+#pragma weak mcsib_sw_workaround_main
+#endif
+
+void cci_disable_cluster_coherency(unsigned long mpidr)
+{
+	unsigned long slave_base;
+	unsigned int config = 0;
+
+	assert(cci_base_addr);
+	slave_base = get_slave_iface_base(mpidr);
+
+	while (mmio_read_32(cci_base_addr + SNP_PENDING_REG) >> SNP_PENDING)
+		;
+
+	config = mmio_read_32(slave_base);
+	config &= ~(DVM_EN_BIT | SNOOP_EN_BIT);
+
+	/* Disable Snoops and DVM messages */
+	mmio_write_32(slave_base, config);
+
+#if ERRATA_MCSIB_SW
+	mcsib_sw_workaround_main();
+#endif
+
+	/* Wait for the dust to settle down */
+	while (mmio_read_32(cci_base_addr + SNP_PENDING_REG) >> SNP_PENDING)
+		;
+}
+
+void cci_secure_switch(unsigned int status)
+{
+	unsigned int config;
+
+	config = mmio_read_32(cci_base_addr + CENTRAL_CTRL_REG);
+	if (status == NS_ACC)
+		config |= SECURE_ACC_EN;
+	else
+		config &= ~SECURE_ACC_EN;
+	mmio_write_32(cci_base_addr + CENTRAL_CTRL_REG, config);
+}
+
+void cci_pmu_secure_switch(unsigned int status)
+{
+	unsigned int config;
+
+	config = mmio_read_32(cci_base_addr + CENTRAL_CTRL_REG);
+	if (status == NS_ACC)
+		config |= PMU_SECURE_ACC_EN;
+	else
+		config &= ~PMU_SECURE_ACC_EN;
+	mmio_write_32(cci_base_addr + CENTRAL_CTRL_REG, config);
+}
+
+void cci_init_sf(void)
+{
+	while (mmio_read_32(cci_base_addr + SNP_PENDING_REG) >> SNP_PENDING)
+		;
+	/* init sf1 */
+	mmio_write_32(cci_base_addr + SF_INIT_REG, TRIG_SF1_INIT);
+	while (mmio_read_32(cci_base_addr + SF_INIT_REG) & TRIG_SF1_INIT)
+		;
+	while (!(mmio_read_32(cci_base_addr + SF_INIT_REG) & SF1_INIT_DONE))
+		;
+	/* init sf2 */
+	mmio_write_32(cci_base_addr + SF_INIT_REG, TRIG_SF2_INIT);
+	while (mmio_read_32(cci_base_addr + SF_INIT_REG) & TRIG_SF2_INIT)
+		;
+	while (!(mmio_read_32(cci_base_addr + SF_INIT_REG) & SF2_INIT_DONE))
+		;
+}
+
+void cci_interrupt_en(void)
+{
+	mmio_setbits_32(cci_base_addr + CENTRAL_CTRL_REG, INT_EN);
+}
+
+unsigned long cci_reg_access(unsigned int op, unsigned long offset,
+			     unsigned long val)
+{
+	unsigned long ret = 0;
+
+	if ((cci_base_addr == 0) || (offset > MSCI_MEMORY_SZ))
+		panic();
+
+	switch (op) {
+	case MCSI_REG_ACCESS_READ:
+		ret = mmio_read_32(cci_base_addr + offset);
+		break;
+	case MCSI_REG_ACCESS_WRITE:
+		mmio_write_32(cci_base_addr + offset, val);
+		dsb();
+		break;
+	case MCSI_REG_ACCESS_SET_BITMASK:
+		mmio_setbits_32(cci_base_addr + offset, val);
+		dsb();
+		break;
+	case MCSI_REG_ACCESS_CLEAR_BITMASK:
+		mmio_clrbits_32(cci_base_addr + offset, val);
+		dsb();
+		break;
+	default:
+		break;
+	}
+	return ret;
+}