mips: ralink: mt7621: define MT7621_SYSC_BASE with __iomem

So that MT7621_SYSC_BASE can be used later in multiple functions without
needing to repeat this __iomem declaration each time
Signed-off-by: John Thomson <git@johnthomson.fastmail.com.au>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

arch/mips/include/asm/mach-ralink/mt7621.h

@@ -7,10 +7,12 @@
 #ifndef _MT7621_REGS_H_
 #define _MT7621_REGS_H_
 
+#define IOMEM(x)			((void __iomem *)(KSEG1ADDR(x)))
+
 #define MT7621_PALMBUS_BASE		0x1C000000
 #define MT7621_PALMBUS_SIZE		0x03FFFFFF
 
-#define MT7621_SYSC_BASE		0x1E000000
+#define MT7621_SYSC_BASE		IOMEM(0x1E000000)
 
 #define SYSC_REG_CHIP_NAME0		0x00
 #define SYSC_REG_CHIP_NAME1		0x04

arch/mips/ralink/mt7621.c

@@ -126,7 +126,6 @@ static void soc_dev_init(struct ralink_soc_info *soc_info, u32 rev)
 
 void __init prom_soc_init(struct ralink_soc_info *soc_info)
 {
-	void __iomem *sysc = (void __iomem *) KSEG1ADDR(MT7621_SYSC_BASE);
 	unsigned char *name = NULL;
 	u32 n0;
 	u32 n1;
@@ -154,8 +153,8 @@ void __init prom_soc_init(struct ralink_soc_info *soc_info)
 		__sync();
 	}
 
-	n0 = __raw_readl(sysc + SYSC_REG_CHIP_NAME0);
-	n1 = __raw_readl(sysc + SYSC_REG_CHIP_NAME1);
+	n0 = __raw_readl(MT7621_SYSC_BASE + SYSC_REG_CHIP_NAME0);
+	n1 = __raw_readl(MT7621_SYSC_BASE + SYSC_REG_CHIP_NAME1);
 
 	if (n0 == MT7621_CHIP_NAME0 && n1 == MT7621_CHIP_NAME1) {
 		name = "MT7621";
@@ -164,7 +163,7 @@ void __init prom_soc_init(struct ralink_soc_info *soc_info)
 		panic("mt7621: unknown SoC, n0:%08x n1:%08x\n", n0, n1);
 	}
 	ralink_soc = MT762X_SOC_MT7621AT;
-	rev = __raw_readl(sysc + SYSC_REG_CHIP_REV);
+	rev = __raw_readl(MT7621_SYSC_BASE + SYSC_REG_CHIP_REV);
 
 	snprintf(soc_info->sys_type, RAMIPS_SYS_TYPE_LEN,
 		"MediaTek %s ver:%u eco:%u",