omap3: mem: Comment enable_gpmc_cs_config more

Expand the "enable the config" comment to explain what the bit shifts
are and define out two of the magic numbers.

Signed-off-by: Tom Rini <trini@ti.com>

arch/arm/cpu/armv7/omap3/mem.c

@@ -105,9 +105,15 @@ void enable_gpmc_cs_config(const u32 *gpmc_config, struct gpmc_cs *cs, u32 base,
 	writel(gpmc_config[3], &cs->config4);
 	writel(gpmc_config[4], &cs->config5);
 	writel(gpmc_config[5], &cs->config6);
-	/* Enable the config */
-	writel((((size & 0xF) << 8) | ((base >> 24) & 0x3F) |
-		(1 << 6)), &cs->config7);
+
+	/*
+	 * Enable the config.  size is the CS size and goes in
+	 * bits 11:8.  We set bit 6 to enable this CS and the base
+	 * address goes into bits 5:0.
+	 */
+	 writel((size << 8) | (GPMC_CS_ENABLE << 6) |
+				 ((base >> 24) & GPMC_BASEADDR_MASK),
+				 &cs->config7);
 	sdelay(2000);
 }
 

arch/arm/include/asm/arch-omap3/mem.h

@@ -259,6 +259,10 @@ enum {
 #define GPMC_SIZE_32M	0xE
 #define GPMC_SIZE_16M	0xF
 
+#define GPMC_BASEADDR_MASK	0x3F
+
+#define GPMC_CS_ENABLE		0x1
+
 #define SMNAND_GPMC_CONFIG1	0x00000800
 #define SMNAND_GPMC_CONFIG2	0x00141400
 #define SMNAND_GPMC_CONFIG3	0x00141400