4 files changed, 94 insertions, 3 deletions

diff --git a/arch/arm/mach-realview/Kconfig b/arch/arm/mach-realview/Kconfig
index dfc9b0bc6eb2..c48e1f2c3349 100644
--- a/arch/arm/mach-realview/Kconfig
+++ b/arch/arm/mach-realview/Kconfig
@@ -70,6 +70,8 @@ config MACH_REALVIEW_PBX
         bool "Support RealView/PBX platform"
         select ARM_GIC
         select HAVE_PATA_PLATFORM
+        select ARCH_SPARSEMEM_ENABLE if CPU_V7 && !HIGH_PHYS_OFFSET
+        select ZONE_DMA if SPARSEMEM
         help
           Include support for the ARM(R) RealView PBX platform.
 
@@ -82,6 +84,7 @@ config REALVIEW_HIGH_PHYS_OFFSET
           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.
+          offset. On the PBX board, disabling this option allows 1GB of
+          RAM to be used with SPARSEMEM.
 
 endmenu
diff --git a/arch/arm/mach-realview/core.c b/arch/arm/mach-realview/core.c
index c21b0fd39652..9f293438e020 100644
--- a/arch/arm/mach-realview/core.c
+++ b/arch/arm/mach-realview/core.c
@@ -59,6 +59,25 @@
 /* used by entry-macro.S and platsmp.c */
 void __iomem *gic_cpu_base_addr;
 
+#ifdef CONFIG_ZONE_DMA
+/*
+ * Adjust the zones if there are restrictions for DMA access.
+ */
+void __init realview_adjust_zones(int node, unsigned long *size,
+                                  unsigned long *hole)
+{
+        unsigned long dma_size = SZ_256M >> PAGE_SHIFT;
+
+        if (!machine_is_realview_pbx() || node || (size[0] <= dma_size))
+                return;
+
+        size[ZONE_NORMAL] = size[0] - dma_size;
+        size[ZONE_DMA] = dma_size;
+        hole[ZONE_NORMAL] = hole[0];
+        hole[ZONE_DMA] = 0;
+}
+#endif
+
 /*
  * This is the RealView sched_clock implementation.  This has
  * a resolution of 41.7ns, and a maximum value of about 179s.
@@ -543,7 +562,7 @@ static int realview_clcd_setup(struct clcd_fb *fb)
         fb->panel               = realview_clcd_panel();
 
         fb->fb.screen_base = dma_alloc_writecombine(&fb->dev->dev, framesize,
-                                                    &dma, GFP_KERNEL);
+                                                    &dma, GFP_KERNEL | GFP_DMA);
         if (!fb->fb.screen_base) {
                 printk(KERN_ERR "CLCD: unable to map framebuffer\n");
                 return -ENOMEM;
diff --git a/arch/arm/mach-realview/include/mach/memory.h b/arch/arm/mach-realview/include/mach/memory.h
index 293c30025e7e..2417bbcf97fd 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
diff --git a/arch/arm/mach-realview/realview_pbx.c b/arch/arm/mach-realview/realview_pbx.c
index 5d09d8b4a1cb..ec39488e2b42 100644
--- a/arch/arm/mach-realview/realview_pbx.c
+++ b/arch/arm/mach-realview/realview_pbx.c
@@ -304,6 +304,26 @@ static struct sys_timer realview_pbx_timer = {
         .init           = realview_pbx_timer_init,
 };
 
+static void realview_pbx_fixup(struct machine_desc *mdesc, struct tag *tags,
+                               char **from, struct meminfo *meminfo)
+{
+#ifdef CONFIG_SPARSEMEM
+        /*
+         * Memory configuration with SPARSEMEM enabled on RealView PBX (see
+         * asm/mach/memory.h for more information).
+         */
+        meminfo->bank[0].start = 0;
+        meminfo->bank[0].size = SZ_256M;
+        meminfo->bank[1].start = 0x20000000;
+        meminfo->bank[1].size = SZ_512M;
+        meminfo->bank[2].start = 0x80000000;
+        meminfo->bank[2].size = SZ_256M;
+        meminfo->nr_banks = 3;
+#else
+        realview_fixup(mdesc, tags, from, meminfo);
+#endif
+}
+
 static void __init realview_pbx_init(void)
 {
         int i;
@@ -345,7 +365,7 @@ MACHINE_START(REALVIEW_PBX, "ARM-RealView PBX")
         .phys_io        = REALVIEW_PBX_UART0_BASE,
         .io_pg_offst    = (IO_ADDRESS(REALVIEW_PBX_UART0_BASE) >> 18) & 0xfffc,
         .boot_params    = PHYS_OFFSET + 0x00000100,
-        .fixup          = realview_fixup,
+        .fixup          = realview_pbx_fixup,
         .map_io         = realview_pbx_map_io,
         .init_irq       = gic_init_irq,
         .timer          = &realview_pbx_timer,