diff --git a/plat/mediatek/mt8173/mt8173_def.h b/plat/mediatek/mt8173/mt8173_def.h
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+++ b/plat/mediatek/mt8173/mt8173_def.h
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+/*
+ * Copyright (c) 2014-2015, ARM Limited and Contributors. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * Redistributions of source code must retain the above copyright notice, this
+ * list of conditions and the following disclaimer.
+ *
+ * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * Neither the name of ARM nor the names of its contributors may be used
+ * to endorse or promote products derived from this software without specific
+ * prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef __PLAT_DEF_H__
+#define __PLAT_DEF_H__
+
+#define MT8173_PRIMARY_CPU	0x0
+
+/* Special value used to verify platform parameters from BL2 to BL3-1 */
+#define MT_BL31_PLAT_PARAM_VAL	0x0f1e2d3c4b5a6978ULL
+
+#define IO_PHYS			(0x10000000)
+#define INFRACFG_AO_BASE	(IO_PHYS + 0x1000)
+#define GPIO_BASE		(IO_PHYS + 0x5000)
+#define SPM_BASE		(IO_PHYS + 0x6000)
+#define RGU_BASE		(IO_PHYS + 0x7000)
+#define PMIC_WRAP_BASE		(IO_PHYS + 0xD000)
+#define MCUCFG_BASE		(IO_PHYS + 0x200000)
+#define TRNG_base		(IO_PHYS + 0x20F000)
+#define MT_GIC_BASE		(IO_PHYS + 0x220000)
+#define PLAT_MT_CCI_BASE	(IO_PHYS + 0x390000)
+
+/* Aggregate of all devices in the first GB */
+#define MTK_DEV_RNG0_BASE	IO_PHYS
+#define MTK_DEV_RNG0_SIZE	0x400000
+#define MTK_DEV_RNG1_BASE	(IO_PHYS + 0x1000000)
+#define MTK_DEV_RNG1_SIZE	0x4000000
+
+/*******************************************************************************
+ * UART related constants
+ ******************************************************************************/
+#define MT8173_UART0_BASE	(IO_PHYS + 0x01002000)
+#define MT8173_UART1_BASE	(IO_PHYS + 0x01003000)
+#define MT8173_UART2_BASE	(IO_PHYS + 0x01004000)
+#define MT8173_UART3_BASE	(IO_PHYS + 0x01005000)
+
+#define MT8173_BAUDRATE		(115200)
+#define MT8173_UART_CLOCK	(26000000)
+
+/*******************************************************************************
+ * System counter frequency related constants
+ ******************************************************************************/
+#define SYS_COUNTER_FREQ_IN_TICKS	13000000
+#define SYS_COUNTER_FREQ_IN_MHZ		13
+
+/*******************************************************************************
+ * GIC-400 & interrupt handling related constants
+ ******************************************************************************/
+
+/* Base MTK_platform compatible GIC memory map */
+#define BASE_GICD_BASE		(MT_GIC_BASE + 0x1000)
+#define BASE_GICC_BASE		(MT_GIC_BASE + 0x2000)
+#define BASE_GICR_BASE		0	/* no GICR in GIC-400 */
+#define BASE_GICH_BASE		(MT_GIC_BASE + 0x4000)
+#define BASE_GICV_BASE		(MT_GIC_BASE + 0x6000)
+#define INT_POL_CTL0		0x10200620
+
+#define GIC_PRIVATE_SIGNALS	(32)
+
+/*******************************************************************************
+ * CCI-400 related constants
+ ******************************************************************************/
+#define PLAT_MT_CCI_CLUSTER0_SL_IFACE_IX	4
+#define PLAT_MT_CCI_CLUSTER1_SL_IFACE_IX	3
+
+/*******************************************************************************
+ * WDT related constants
+ ******************************************************************************/
+#define MTK_WDT_BASE		(RGU_BASE + 0)
+#define MTK_WDT_SWRST		(MTK_WDT_BASE + 0x0014)
+
+#define MTK_WDT_MODE_DUAL_MODE	0x0040
+#define MTK_WDT_MODE_IRQ	0x0008
+#define MTK_WDT_MODE_KEY	0x22000000
+#define MTK_WDT_MODE_EXTEN	0x0004
+#define MTK_WDT_SWRST_KEY	0x1209
+
+/* FIQ platform related define */
+#define MT_IRQ_SEC_SGI_0	8
+#define MT_IRQ_SEC_SGI_1	9
+#define MT_IRQ_SEC_SGI_2	10
+#define MT_IRQ_SEC_SGI_3	11
+#define MT_IRQ_SEC_SGI_4	12
+#define MT_IRQ_SEC_SGI_5	13
+#define MT_IRQ_SEC_SGI_6	14
+#define MT_IRQ_SEC_SGI_7	15
+
+#endif /* __PLAT_DEF_H__ */