arm: vf610: add DDR_SEL_PAD_CONTR register

Set DDR_SEL_PAD_CONTR register explicitly to DDR3 which solves RAM
issues with newer silicon (1.1). This register was added in revision
4 of the Vybrid Reference Manual.

Signed-off-by: Stefan Agner <stefan@agner.ch>

arch/arm/include/asm/arch-vf610/imx-regs.h

@@ -215,6 +215,7 @@
 #define DDRMC_CR139_PHY_WRLV_EN(v)			((v) & 0xff)
 #define DDRMC_CR154_PAD_ZQ_EARLY_CMP_EN_TIMER(v)	(((v) & 0x1f) << 27)
 #define DDRMC_CR154_PAD_ZQ_MODE(v)			(((v) & 0x3) << 21)
+#define DDRMC_CR154_DDR_SEL_PAD_CONTR(v)		(((v) & 0x3) << 18)
 #define DDRMC_CR155_AXI0_AWCACHE			(1 << 10)
 #define DDRMC_CR155_PAD_ODT_BYTE1(v)			((v) & 0x7)
 #define DDRMC_CR158_TWR(v)				((v) & 0x3f)

board/freescale/vf610twr/vf610twr.c

@@ -217,7 +217,8 @@ void ddr_ctrl_init(void)
 		&ddrmr->cr[139]);
 
 	writel(DDRMC_CR154_PAD_ZQ_EARLY_CMP_EN_TIMER(13) |
-		DDRMC_CR154_PAD_ZQ_MODE(1), &ddrmr->cr[154]);
+		DDRMC_CR154_PAD_ZQ_MODE(1) |
+		DDRMC_CR154_DDR_SEL_PAD_CONTR(3), &ddrmr->cr[154]);
 	writel(DDRMC_CR155_AXI0_AWCACHE | DDRMC_CR155_PAD_ODT_BYTE1(2),
 		&ddrmr->cr[155]);
 	writel(DDRMC_CR158_TWR(6), &ddrmr->cr[158]);