RealView: Add sparsemem support for the RealView PBX platform

The RealView PBX board has two 512MB blocks of memory - one at
0x70000000 (with 256MB mirror at 0) and another at 0x20000000. Only the
block at 0x70000000 (or the mirror at 0) may be used for DMA (e.g.
framebuffer). This patch adds the sparsemem definitions to allow the use
of all the memory split as follows:

  256MB @ 0x00000000 (ZONE_DMA)
  512MB @ 0x20000000 (ZONE_NORMAL)
  256MB @ 0x80000000 (ZONE_NORMAL)

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

1 files changed, 49 insertions, 0 deletions

diff --git a/arch/arm/mach-realview/include/mach/memory.h b/arch/arm/mach-realview/include/mach/memory.h
index 293c30025e7..2417bbcf97f 100644
--- a/arch/arm/mach-realview/include/mach/memory.h
+++ b/arch/arm/mach-realview/include/mach/memory.h
@@ -29,4 +29,53 @@
 #define PHYS_OFFSET		UL(0x00000000)
 #endif
 
+#if !defined(__ASSEMBLY__) && defined(CONFIG_ZONE_DMA)
+extern void realview_adjust_zones(int node, unsigned long *size,
+				  unsigned long *hole);
+#define arch_adjust_zones(node, size, hole) \
+	realview_adjust_zones(node, size, hole)
+
+#define ISA_DMA_THRESHOLD	(PHYS_OFFSET + SZ_256M - 1)
+#define MAX_DMA_ADDRESS		(PAGE_OFFSET + SZ_256M)
+#endif
+
+#ifdef CONFIG_SPARSEMEM
+
+/*
+ * Sparsemem definitions for RealView PBX.
+ *
+ * The RealView PBX board has another block of 512MB of RAM at 0x20000000,
+ * however only the block at 0x70000000 (or the 256MB mirror at 0x00000000)
+ * may be used for DMA.
+ *
+ * The macros below define a section size of 256MB and a non-linear virtual to
+ * physical mapping:
+ *
+ * 256MB @ 0x00000000 -> PAGE_OFFSET
+ * 512MB @ 0x20000000 -> PAGE_OFFSET + 0x10000000
+ * 256MB @ 0x80000000 -> PAGE_OFFSET + 0x30000000
+ */
+#ifdef CONFIG_REALVIEW_HIGH_PHYS_OFFSET
+#error "SPARSEMEM not available with REALVIEW_HIGH_PHYS_OFFSET"
+#endif
+
+#define MAX_PHYSMEM_BITS	32
+#define SECTION_SIZE_BITS	28
+
+/* bank page offsets */
+#define PAGE_OFFSET1	(PAGE_OFFSET + 0x10000000)
+#define PAGE_OFFSET2	(PAGE_OFFSET + 0x30000000)
+
+#define __phys_to_virt(phys)						\
+	((phys) >= 0x80000000 ?	(phys) - 0x80000000 + PAGE_OFFSET2 :	\
+	 (phys) >= 0x20000000 ?	(phys) - 0x20000000 + PAGE_OFFSET1 :	\
+	 (phys) + PAGE_OFFSET)
+
+#define __virt_to_phys(virt)						\
+	 ((virt) >= PAGE_OFFSET2 ? (virt) - PAGE_OFFSET2 + 0x80000000 :	\
+	  (virt) >= PAGE_OFFSET1 ? (virt) - PAGE_OFFSET1 + 0x20000000 :	\
+	  (virt) - PAGE_OFFSET)
+
+#endif	/* CONFIG_SPARSEMEM */
+
 #endif