stm32mp1: Add env_get_location()

In case of several environment location support, env_get_location
is needed to select the correct location depending of the boot
device .

Signed-off-by: Patrice Chotard <patrice.chotard@st.com>
diff --git a/board/st/stm32mp1/stm32mp1.c b/board/st/stm32mp1/stm32mp1.c
index 316cd48..4f7d24a 100644
--- a/board/st/stm32mp1/stm32mp1.c
+++ b/board/st/stm32mp1/stm32mp1.c
@@ -7,6 +7,7 @@
 #include <config.h>
 #include <clk.h>
 #include <dm.h>
+#include <environment.h>
 #include <g_dnl.h>
 #include <generic-phy.h>
 #include <i2c.h>
@@ -506,6 +507,28 @@
 	setup_led(LEDST_OFF);
 }
 
+enum env_location env_get_location(enum env_operation op, int prio)
+{
+	u32 bootmode = get_bootmode();
+
+	if (prio)
+		return ENVL_UNKNOWN;
+
+	switch (bootmode & TAMP_BOOT_DEVICE_MASK) {
+#ifdef CONFIG_ENV_IS_IN_EXT4
+	case BOOT_FLASH_SD:
+	case BOOT_FLASH_EMMC:
+		return ENVL_EXT4;
+#endif
+#ifdef CONFIG_ENV_IS_IN_UBI
+	case BOOT_FLASH_NAND:
+		return ENVL_UBI;
+#endif
+	default:
+		return ENVL_NOWHERE;
+	}
+}
+
 #if defined(CONFIG_ENV_IS_IN_EXT4)
 const char *env_ext4_get_intf(void)
 {