imx: mx6: Implement mmc_get_env_part

commit 216d286c7e [imx: mx6: implement
mmc_get_env_dev] introduced selection of the environment device according
to the boot device when booting from SD/MMC.

Extend this functionality for also selecting the device partition.

Signed-off-by: Soeren Moch <smoch@web.de>

arch/arm/cpu/armv7/mx6/soc.c

@@ -21,6 +21,7 @@
 #include <asm/arch/crm_regs.h>
 #include <dm.h>
 #include <imx_thermal.h>
+#include <mmc.h>
 
 enum ldo_reg {
 	LDO_ARM,
@@ -355,7 +356,7 @@ __weak int board_mmc_get_env_dev(int devno)
 	return CONFIG_SYS_MMC_ENV_DEV;
 }
 
-int mmc_get_env_dev(void)
+static int mmc_get_boot_dev(void)
 {
 	struct src *src_regs = (struct src *)SRC_BASE_ADDR;
 	u32 soc_sbmr = readl(&src_regs->sbmr1);
@@ -370,15 +371,44 @@ int mmc_get_env_dev(void)
 	 */
 	bootsel = (soc_sbmr & 0x000000FF) >> 6;
 
-	/* If not boot from sd/mmc, use default value */
+	/* No boot from sd/mmc */
 	if (bootsel != 1)
-		return CONFIG_SYS_MMC_ENV_DEV;
+		return -1;
 
 	/* BOOT_CFG2[3] and BOOT_CFG2[4] */
 	devno = (soc_sbmr & 0x00001800) >> 11;
 
+	return devno;
+}
+
+int mmc_get_env_dev(void)
+{
+	int devno = mmc_get_boot_dev();
+
+	/* If not boot from sd/mmc, use default value */
+	if (devno < 0)
+		return CONFIG_SYS_MMC_ENV_DEV;
+
 	return board_mmc_get_env_dev(devno);
 }
+
+#ifdef CONFIG_SYS_MMC_ENV_PART
+__weak int board_mmc_get_env_part(int devno)
+{
+	return CONFIG_SYS_MMC_ENV_PART;
+}
+
+uint mmc_get_env_part(struct mmc *mmc)
+{
+	int devno = mmc_get_boot_dev();
+
+	/* If not boot from sd/mmc, use default value */
+	if (devno < 0)
+		return CONFIG_SYS_MMC_ENV_PART;
+
+	return board_mmc_get_env_part(devno);
+}
+#endif
 #endif
 
 int board_postclk_init(void)