allwinner: Adjust memory mapping to fit into 256MB

At the moment we map as much of the DRAM into EL3 as possible, however
we actually don't use it. The only exception is the secure DRAM for
BL32 (if that is configured).

To decrease the memory footprint of ATF, we save on some page tables by
reducing the memory mapping to the actually required regions: SRAM, device
MMIO, secure DRAM and U-Boot (to be used later).
This introduces a non-identity mapping for the DRAM regions.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
diff --git a/plat/allwinner/common/include/platform_def.h b/plat/allwinner/common/include/platform_def.h
index b46d410..b7cf30f 100644
--- a/plat/allwinner/common/include/platform_def.h
+++ b/plat/allwinner/common/include/platform_def.h
@@ -18,11 +18,17 @@
 /* The traditional U-Boot load address is 160MB into DRAM, so at 0x4a000000 */
 #define PLAT_SUNXI_NS_IMAGE_OFFSET	(SUNXI_DRAM_BASE + (160U << 20))
 
+/* How much memory to reserve as secure for BL32, if configured */
+#define SUNXI_DRAM_SEC_SIZE		(32U << 20)
+
+/* How much DRAM to map */
+#define SUNXI_DRAM_MAP_SIZE		(64U << 20)
+
 #define CACHE_WRITEBACK_SHIFT		6
 #define CACHE_WRITEBACK_GRANULE		(1 << CACHE_WRITEBACK_SHIFT)
 
 #define MAX_MMAP_REGIONS		(4 + PLATFORM_MMAP_REGIONS)
-#define MAX_XLAT_TABLES			2
+#define MAX_XLAT_TABLES			1
 
 #define PLAT_MAX_PWR_LVL_STATES		U(2)
 #define PLAT_MAX_RET_STATE		U(1)
@@ -34,13 +40,13 @@
 					 PLATFORM_CORE_COUNT)
 
 #define PLAT_PHY_ADDR_SPACE_SIZE	(1ULL << 32)
-#define PLAT_VIRT_ADDR_SPACE_SIZE	(1ULL << 32)
+#define PLAT_VIRT_ADDR_SPACE_SIZE	(1ULL << 28)
 
 #define PLATFORM_CLUSTER_COUNT		1
 #define PLATFORM_CORE_COUNT		(PLATFORM_CLUSTER_COUNT * \
 					 PLATFORM_MAX_CPUS_PER_CLUSTER)
 #define PLATFORM_MAX_CPUS_PER_CLUSTER	4
-#define PLATFORM_MMAP_REGIONS		3
+#define PLATFORM_MMAP_REGIONS		4
 #define PLATFORM_STACK_SIZE		(0x1000 / PLATFORM_CORE_COUNT)
 
 #ifndef SPD_none
diff --git a/plat/allwinner/common/sunxi_common.c b/plat/allwinner/common/sunxi_common.c
index fc9bf20..ef6f04c 100644
--- a/plat/allwinner/common/sunxi_common.c
+++ b/plat/allwinner/common/sunxi_common.c
@@ -17,8 +17,12 @@
 			MT_MEMORY | MT_RW | MT_SECURE),
 	MAP_REGION_FLAT(SUNXI_DEV_BASE, SUNXI_DEV_SIZE,
 			MT_DEVICE | MT_RW | MT_SECURE),
-	MAP_REGION_FLAT(SUNXI_DRAM_BASE, SUNXI_DRAM_SIZE,
-			MT_MEMORY | MT_RW | MT_NS),
+	MAP_REGION(SUNXI_DRAM_BASE, SUNXI_DRAM_VIRT_BASE, SUNXI_DRAM_SEC_SIZE,
+			MT_MEMORY | MT_RW | MT_SECURE),
+	MAP_REGION(PLAT_SUNXI_NS_IMAGE_OFFSET,
+		   SUNXI_DRAM_VIRT_BASE + SUNXI_DRAM_SEC_SIZE,
+		   SUNXI_DRAM_MAP_SIZE,
+		   MT_MEMORY | MT_RO | MT_NS),
 	{},
 };
 
diff --git a/plat/allwinner/sun50i_a64/include/sunxi_mmap.h b/plat/allwinner/sun50i_a64/include/sunxi_mmap.h
index 7d46487..28b1dd3 100644
--- a/plat/allwinner/sun50i_a64/include/sunxi_mmap.h
+++ b/plat/allwinner/sun50i_a64/include/sunxi_mmap.h
@@ -21,7 +21,7 @@
 #define SUNXI_DEV_BASE			0x01000000
 #define SUNXI_DEV_SIZE			0x01000000
 #define SUNXI_DRAM_BASE			0x40000000
-#define SUNXI_DRAM_SIZE			0x80000000
+#define SUNXI_DRAM_VIRT_BASE		0x02000000
 
 /* Memory-mapped devices */
 #define SUNXI_CPU_MBIST_BASE		0x01502000
diff --git a/plat/allwinner/sun50i_h6/include/sunxi_mmap.h b/plat/allwinner/sun50i_h6/include/sunxi_mmap.h
index f2d5aed..901e536 100644
--- a/plat/allwinner/sun50i_h6/include/sunxi_mmap.h
+++ b/plat/allwinner/sun50i_h6/include/sunxi_mmap.h
@@ -21,7 +21,7 @@
 #define SUNXI_DEV_BASE			0x01000000
 #define SUNXI_DEV_SIZE			0x09000000
 #define SUNXI_DRAM_BASE			0x40000000
-#define SUNXI_DRAM_SIZE			0xc0000000
+#define SUNXI_DRAM_VIRT_BASE		0x0a000000
 
 /* Memory-mapped devices */
 #define SUNXI_SYSCON_BASE		0x03000000