ARM: EXYNOS: use four additional chipid bits to identify EXYNOS family

Use chipid[27:20] bits to identify the EXYNOS family while setting
up the serial port during the uncompression setup. This uses four
additional bits of chipid to identify the EXYNOS family since this
is required for identifying EXYNOS5420 SoC.
Signed-off-by: Chander Kashyap <chander.kashyap@linaro.org>
Signed-off-by: Thomas Abraham <thomas.abraham@linaro.org>
Reviewed-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>

arch/arm/mach-exynos/include/mach/uncompress.h

@@ -31,13 +31,12 @@ static void arch_detect_cpu(void)
 
 	/*
 	 * product_id is bits 31:12
-	 *    bits 23:20 describe the exynosX family
-	 *
+	 * bits 23:20 describe the exynosX family
+	 * bits 27:24 describe the exynosX family in exynos5420
 	 */
 	chip_id >>= 20;
-	chip_id &= 0xf;
 
-	if (chip_id == 0x5)
+	if ((chip_id & 0x0f) == 0x5 || (chip_id & 0xf0) == 0x50)
 		uart_base = (volatile u8 *)EXYNOS5_PA_UART + (S3C_UART_OFFSET * CONFIG_S3C_LOWLEVEL_UART_PORT);
 	else
 		uart_base = (volatile u8 *)EXYNOS4_PA_UART + (S3C_UART_OFFSET * CONFIG_S3C_LOWLEVEL_UART_PORT);