RealView: Allow PHYS_OFFSET at 0x70000000

RealView boards like PB11MPCore have 512MB of RAM available contiguously
at 0x70000000. Half of the memory is mirrored at 0x00000000 for
backwards compatibility. This patch adds the
CONFIG_REALVIEW_HIGH_PHYS_OFFSET option option to change the physical
base address so that the full amount of RAM is available to Linux. Note
that the EB board has 256MB of RAM also mirrored at 0x70000000, the only
board without this feature being PB1176.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

arch/arm/mach-realview/Kconfig

@@ -37,4 +37,15 @@ config MACH_REALVIEW_PB1176
 	help
 	  Include support for the ARM(R) RealView ARM1176 Platform Baseboard.
 
+config REALVIEW_HIGH_PHYS_OFFSET
+	bool "High physical base address for the RealView platform"
+	depends on !MACH_REALVIEW_PB1176
+	default y
+	help
+	  RealView boards other than PB1176 have the RAM available at
+	  0x70000000, 256MB of which being mirrored at 0x00000000. If
+	  the board supports 512MB of RAM, this option allows the
+	  memory to be accessed contiguously at the high physical
+	  offset.
+
 endmenu

arch/arm/mach-realview/Makefile.boot

+ifeq ($(CONFIG_REALVIEW_HIGH_PHYS_OFFSET),y)
+   zreladdr-y	:= 0x70008000
+params_phys-y	:= 0x70000100
+initrd_phys-y	:= 0x70800000
+else
    zreladdr-y	:= 0x00008000
 params_phys-y	:= 0x00000100
 initrd_phys-y	:= 0x00800000
-
+endif

arch/arm/mach-realview/include/mach/memory.h

@@ -23,7 +23,11 @@
 /*
  * Physical DRAM offset.
  */
+#ifdef CONFIG_REALVIEW_HIGH_PHYS_OFFSET
+#define PHYS_OFFSET		UL(0x70000000)
+#else
 #define PHYS_OFFSET		UL(0x00000000)
+#endif
 
 /*
  * Virtual view <-> DMA view memory address translations

arch/arm/mach-realview/realview_eb.c

@@ -392,7 +392,7 @@ MACHINE_START(REALVIEW_EB, "ARM-RealView EB")
 	/* Maintainer: ARM Ltd/Deep Blue Solutions Ltd */
 	.phys_io	= REALVIEW_EB_UART0_BASE,
 	.io_pg_offst	= (IO_ADDRESS(REALVIEW_EB_UART0_BASE) >> 18) & 0xfffc,
-	.boot_params	= 0x00000100,
+	.boot_params	= PHYS_OFFSET + 0x00000100,
 	.map_io		= realview_eb_map_io,
 	.init_irq	= gic_init_irq,
 	.timer		= &realview_eb_timer,

arch/arm/mach-realview/realview_pb1176.c

@@ -284,7 +284,7 @@ MACHINE_START(REALVIEW_PB1176, "ARM-RealView PB1176")
 	/* Maintainer: ARM Ltd/Deep Blue Solutions Ltd */
 	.phys_io	= REALVIEW_PB1176_UART0_BASE,
 	.io_pg_offst	= (IO_ADDRESS(REALVIEW_PB1176_UART0_BASE) >> 18) & 0xfffc,
-	.boot_params	= 0x00000100,
+	.boot_params	= PHYS_OFFSET + 0x00000100,
 	.map_io		= realview_pb1176_map_io,
 	.init_irq	= gic_init_irq,
 	.timer		= &realview_pb1176_timer,

arch/arm/mach-realview/realview_pb11mp.c

@@ -334,7 +334,7 @@ MACHINE_START(REALVIEW_PB11MP, "ARM-RealView PB11MPCore")
 	/* Maintainer: ARM Ltd/Deep Blue Solutions Ltd */
 	.phys_io	= REALVIEW_PB11MP_UART0_BASE,
 	.io_pg_offst	= (IO_ADDRESS(REALVIEW_PB11MP_UART0_BASE) >> 18) & 0xfffc,
-	.boot_params	= 0x00000100,
+	.boot_params	= PHYS_OFFSET + 0x00000100,
 	.map_io		= realview_pb11mp_map_io,
 	.init_irq	= gic_init_irq,
 	.timer		= &realview_pb11mp_timer,