1 files changed, 39 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;
 	}