ARM: BeagleBoard-X15: Enable VTT regulator

BeagleBoard-X15 uses a vtt regulator for DDR3 termination
and this is controlled by gpio7_11. Configuring gpio7_11.

Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Reviewed-by: Tom Rini <trini@konsulko.com>

board/ti/beagle_x15/board.c

@@ -14,6 +14,8 @@
 #include <usb.h>
 #include <asm/omap_common.h>
 #include <asm/emif.h>
+#include <asm/gpio.h>
+#include <asm/arch/gpio.h>
 #include <asm/arch/clock.h>
 #include <asm/arch/dra7xx_iodelay.h>
 #include <asm/arch/sys_proto.h>
@@ -30,6 +32,9 @@
 
 DECLARE_GLOBAL_DATA_PTR;
 
+/* GPIO 7_11 */
+#define GPIO_DDR_VTT_EN 203
+
 const struct omap_sysinfo sysinfo = {
 	"Board: BeagleBoard x15\n"
 };
@@ -404,3 +409,21 @@ int board_eth_init(bd_t *bis)
 	return ret;
 }
 #endif
+
+#ifdef CONFIG_BOARD_EARLY_INIT_F
+/* VTT regulator enable */
+static inline void vtt_regulator_enable(void)
+{
+	if (omap_hw_init_context() == OMAP_INIT_CONTEXT_UBOOT_AFTER_SPL)
+		return;
+
+	gpio_request(GPIO_DDR_VTT_EN, "ddr_vtt_en");
+	gpio_direction_output(GPIO_DDR_VTT_EN, 1);
+}
+
+int board_early_init_f(void)
+{
+	vtt_regulator_enable();
+	return 0;
+}
+#endif

include/configs/beagle_x15.h

@@ -18,6 +18,8 @@
 #define CONFIG_IODELAY_RECALIBRATION
 #endif
 
+#define CONFIG_BOARD_EARLY_INIT_F
+
 #define CONFIG_NR_DRAM_BANKS		2
 
 #define CONFIG_ENV_SIZE			(64 << 10)