3 files changed, 50 insertions, 4 deletions

diff --git a/arch/sh/boards/mach-sdk7786/fpga.c b/arch/sh/boards/mach-sdk7786/fpga.c
index 99f903c8b238..3e4ec66a0417 100644
--- a/arch/sh/boards/mach-sdk7786/fpga.c
+++ b/arch/sh/boards/mach-sdk7786/fpga.c
@@ -11,9 +11,44 @@
 #include <linux/io.h>
 #include <linux/bcd.h>
 #include <mach/fpga.h>
+#include <asm/sizes.h>
 
-#define FPGA_REGS_BASE  0x07fff800
-#define FPGA_REGS_SIZE  0x490
+#define FPGA_REGS_OFFSET        0x03fff800
+#define FPGA_REGS_SIZE          0x490
+
+/*
+ * The FPGA can be mapped in any of the generally available areas,
+ * so we attempt to scan for it using the fixed SRSTR read magic.
+ *
+ * Once the FPGA is located, the rest of the mapping data for the other
+ * components can be determined dynamically from its section mapping
+ * registers.
+ */
+static void __iomem *sdk7786_fpga_probe(void)
+{
+        unsigned long area;
+        void __iomem *base;
+
+        /*
+         * Iterate over all of the areas where the FPGA could be mapped.
+         * The possible range is anywhere from area 0 through 6, area 7
+         * is reserved.
+         */
+        for (area = PA_AREA0; area < PA_AREA7; area += SZ_64M) {
+                base = ioremap_nocache(area + FPGA_REGS_OFFSET, FPGA_REGS_SIZE);
+                if (!base) {
+                        /* Failed to remap this area, move along. */
+                        continue;
+                }
+
+                if (ioread16(base + SRSTR) == SRSTR_MAGIC)
+                        return base;    /* Found it! */
+
+                iounmap(base);
+        }
+
+        return NULL;
+}
 
 void __iomem *sdk7786_fpga_base;
 
@@ -21,9 +56,9 @@ void __init sdk7786_fpga_init(void)
 {
         u16 version, date;
 
-        sdk7786_fpga_base = ioremap_nocache(FPGA_REGS_BASE, FPGA_REGS_SIZE);
+        sdk7786_fpga_base = sdk7786_fpga_probe();
         if (unlikely(!sdk7786_fpga_base)) {
-                panic("FPGA remapping failed.\n");
+                panic("FPGA detection failed.\n");
                 return;
         }
 
diff --git a/arch/sh/include/cpu-sh4/cpu/addrspace.h b/arch/sh/include/cpu-sh4/cpu/addrspace.h
index a3fa733c1c7d..d51da25da72c 100644
--- a/arch/sh/include/cpu-sh4/cpu/addrspace.h
+++ b/arch/sh/include/cpu-sh4/cpu/addrspace.h
@@ -28,6 +28,15 @@
 #define P4SEG_TLB_DATA  0xf7000000
 #define P4SEG_REG_BASE  0xff000000
 
+#define PA_AREA0        0x00000000
+#define PA_AREA1        0x04000000
+#define PA_AREA2        0x08000000
+#define PA_AREA3        0x0c000000
+#define PA_AREA4        0x10000000
+#define PA_AREA5        0x14000000
+#define PA_AREA6        0x18000000
+#define PA_AREA7        0x1c000000
+
 #define PA_AREA5_IO     0xb4000000      /* Area 5 IO Memory */
 #define PA_AREA6_IO     0xb8000000      /* Area 6 IO Memory */
 
diff --git a/arch/sh/include/mach-sdk7786/mach/fpga.h b/arch/sh/include/mach-sdk7786/mach/fpga.h
index a85d9853d34f..2120d67dec70 100644
--- a/arch/sh/include/mach-sdk7786/mach/fpga.h
+++ b/arch/sh/include/mach-sdk7786/mach/fpga.h
@@ -6,6 +6,8 @@
 #include <linux/bitops.h>
 
 #define SRSTR           0x000
+#define  SRSTR_MAGIC    0x1971  /* Fixed magical read value */
+
 #define INTASR          0x010
 #define INTAMR          0x020
 #define MODSWR          0x030