board/freescale/common: Check IR chip mode for VID support

IR chip on all the boards are required to be used in Intel mode
to support VID. VDD will not be adjusted if IR chip is used in
other modes.

Signed-off-by: Ying Zhang <b40530@freescale.com>
Reviewed-by: York Sun <york.sun@nxp.com>
diff --git a/board/freescale/common/vid.c b/board/freescale/common/vid.c
index f1bed51..1ea1b88 100644
--- a/board/freescale/common/vid.c
+++ b/board/freescale/common/vid.c
@@ -292,7 +292,7 @@
 		(void __iomem *)(CONFIG_SYS_MPC85xx_GUTS_ADDR);
 #endif
 	u32 fusesr;
-	u8 vid;
+	u8 vid, buf;
 	int vdd_target, vdd_current, vdd_last;
 	int ret, i2caddress;
 	unsigned long vdd_string_override;
@@ -346,6 +346,21 @@
 		debug("VID: IR Chip found on I2C address 0x%02x\n", i2caddress);
 	}
 
+	/* check IR chip work on Intel mode*/
+	ret = i2c_read(i2caddress,
+		       IR36021_INTEL_MODE_OOFSET,
+		       1, (void *)&buf, 1);
+	if (ret) {
+		printf("VID: failed to read IR chip mode.\n");
+		ret = -1;
+		goto exit;
+	}
+	if ((buf & IR36021_MODE_MASK) != IR36021_INTEL_MODE) {
+		printf("VID: IR Chip is not used in Intel mode.\n");
+		ret = -1;
+		goto exit;
+	}
+
 	/* get the voltage ID from fuse status register */
 	fusesr = in_be32(&gur->dcfg_fusesr);
 	/*