diff --git a/plat/mediatek/mt8173/include/platform_def.h b/plat/mediatek/mt8173/include/platform_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 __PLATFORM_DEF_H__
+#define __PLATFORM_DEF_H__
+
+#define DEBUG_XLAT_TABLE 0
+
+/*******************************************************************************
+ * Platform binary types for linking
+ ******************************************************************************/
+#define PLATFORM_LINKER_FORMAT		"elf64-littleaarch64"
+#define PLATFORM_LINKER_ARCH		aarch64
+
+/*******************************************************************************
+ * Generic platform constants
+ ******************************************************************************/
+
+/* Size of cacheable stacks */
+#if DEBUG_XLAT_TABLE
+#define PLATFORM_STACK_SIZE 0x800
+#elif IMAGE_BL1
+#define PLATFORM_STACK_SIZE 0x440
+#elif IMAGE_BL2
+#define PLATFORM_STACK_SIZE 0x400
+#elif IMAGE_BL31
+#define PLATFORM_STACK_SIZE 0x800
+#elif IMAGE_BL32
+#define PLATFORM_STACK_SIZE 0x440
+#endif
+
+#define FIRMWARE_WELCOME_STR		"Booting Trusted Firmware\n"
+
+#define PLATFORM_MAX_AFFLVL		MPIDR_AFFLVL2
+#define PLATFORM_SYSTEM_COUNT		1
+#define PLATFORM_CLUSTER_COUNT		2
+#define PLATFORM_CLUSTER0_CORE_COUNT	4
+#define PLATFORM_CLUSTER1_CORE_COUNT	2
+#define PLATFORM_CORE_COUNT		(PLATFORM_CLUSTER1_CORE_COUNT +	\
+					 PLATFORM_CLUSTER0_CORE_COUNT)
+#define PLATFORM_MAX_CPUS_PER_CLUSTER	4
+#define PLATFORM_NUM_AFFS		(PLATFORM_SYSTEM_COUNT +	\
+					 PLATFORM_CLUSTER_COUNT +	\
+					 PLATFORM_CORE_COUNT)
+
+/*******************************************************************************
+ * Platform memory map related constants
+ ******************************************************************************/
+/* TF txet, ro, rw, internal SRAM, Size: release: 80KB, debug: 92KB */
+#define TZRAM_BASE		(0x100000)
+#if DEBUG
+#define TZRAM_SIZE		(0x20000)
+#else
+#define TZRAM_SIZE		(0x20000)
+#endif
+
+/* xlat_table , coherence ram, 64KB */
+#define TZRAM2_BASE		(TZRAM_BASE + TZRAM_SIZE)
+#define TZRAM2_SIZE		(0x10000)
+
+/*******************************************************************************
+ * BL31 specific defines.
+ ******************************************************************************/
+/*
+ * Put BL3-1 at the top of the Trusted SRAM (just below the shared memory, if
+ * present). BL31_BASE is calculated using the current BL3-1 debug size plus a
+ * little space for growth.
+ */
+#define BL31_BASE		(TZRAM_BASE + 0x1000)
+#define BL31_LIMIT		(TZRAM_BASE + TZRAM_SIZE)
+#define TZRAM2_LIMIT		(TZRAM2_BASE + TZRAM2_SIZE)
+
+/*******************************************************************************
+ * Platform specific page table and MMU setup constants
+ ******************************************************************************/
+#define ADDR_SPACE_SIZE		(1ull << 32)
+#define MAX_XLAT_TABLES		4
+#define MAX_MMAP_REGIONS	16
+
+/*******************************************************************************
+ * Declarations and constants to access the mailboxes safely. Each mailbox is
+ * aligned on the biggest cache line size in the platform. This is known only
+ * to the platform as it might have a combination of integrated and external
+ * caches. Such alignment ensures that two maiboxes do not sit on the same cache
+ * line at any cache level. They could belong to different cpus/clusters &
+ * get written while being protected by different locks causing corruption of
+ * a valid mailbox address.
+ ******************************************************************************/
+#define CACHE_WRITEBACK_SHIFT	6
+#define CACHE_WRITEBACK_GRANULE	(1 << CACHE_WRITEBACK_SHIFT)
+
+#endif /* __PLATFORM_DEF_H__ */