powerpc/85xx: Read board switch settings on p1_p2_rdb

PCA9557 is parallel I/O expansion device on I2C bus which stores various
board switch settings like NOR Flash-Bank selection, SD Data width.

On board:
switch SW5[6] is to select width for eSDHC
        ON  - 4-bit [Enable eSPI]
        OFF - 8-bit [Disable eSPI]

switch SW4[8] is to select NOR Flash Bank for Booting
        OFF - Primary Bank
        ON  - Secondary Bank

Read board switch settings on p1_p2_rdb and configure corresponding
eSDHC width.

Signed-off-by: Priyanka Jain <Priyanka.Jain@freescale.com>
Signed-off-by: Dipen Dudhat <dipen.dudhat@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

board/freescale/p1_p2_rdb/p1_p2_rdb.c

@@ -35,6 +35,7 @@
 #include <vsc7385.h>
 #include <netdev.h>
 #include <rtc.h>
+#include <i2c.h>
 
 DECLARE_GLOBAL_DATA_PTR;
 
@@ -142,6 +143,30 @@ int board_early_init_r(void)
 {
 	const unsigned int flashbase = CONFIG_SYS_FLASH_BASE;
 	const u8 flash_esel = find_tlb_idx((void *)flashbase, 1);
+	volatile ccsr_gur_t *gur = (void *)(CONFIG_SYS_MPC85xx_GUTS_ADDR);
+	unsigned int orig_bus = i2c_get_bus_num();
+	u8 i2c_data;
+
+	i2c_set_bus_num(1);
+	if (i2c_read(CONFIG_SYS_I2C_PCA9557_ADDR, 0,
+		1, &i2c_data, sizeof(i2c_data)) == 0) {
+		if (i2c_data & 0x2)
+			puts("NOR Flash Bank : Secondary\n");
+		else
+			puts("NOR Flash Bank : Primary\n");
+
+		if (i2c_data & 0x1) {
+			setbits_be32(&gur->pmuxcr, MPC85xx_PMUXCR_SD_DATA);
+			puts("SD/MMC : 8-bit Mode\n");
+			puts("eSPI : Disabled\n");
+		} else {
+			puts("SD/MMC : 4-bit Mode\n");
+			puts("eSPI : Enabled\n");
+		}
+	} else {
+		puts("Failed reading I2C Chip 0x18 on bus 1\n");
+	}
+	i2c_set_bus_num(orig_bus);
 
 	/*
 	 * Remap Boot flash region to caching-inhibited

include/configs/P1_P2_RDB.h

@@ -362,6 +362,8 @@ extern unsigned long get_board_sys_clk(unsigned long dummy);
 #define CONFIG_SYS_I2C_EEPROM_ADDR_LEN 1
 #define CONFIG_SYS_EEPROM_BUS_NUM	1
 
+#define CONFIG_SYS_I2C_PCA9557_ADDR	0x18
+
 #define CONFIG_RTC_DS1337
 #define CONFIG_SYS_RTC_DS1337_NOOSC
 #define CONFIG_SYS_I2C_RTC_ADDR                0x68