[U-Boot] env_mmc: Fix crashing bug encountered after enabling ARM relocation

[Steve Sakoman <steve@sakoman.com>]

The crash was occuring in env_relocate because it was being called prior
to mmc_initialize.  This patch moves the MMC initialization earlier in
the init process.

This patch also cleans up the env_relocate_spec code in env_mmc.c

Developed jointly with Stefano Babic

Signed-off-by: Steve Sakoman <steve.sakoman@linaro.org>
---

diff --git a/arch/arm/lib/board.c b/arch/arm/lib/board.c
index 5f2dfd0..0e2f129 100644
--- a/arch/arm/lib/board.c
+++ b/arch/arm/lib/board.c
@@ -779,6 +779,11 @@ void board_init_r (gd_t *id, ulong dest_addr)
 	onenand_init();
 #endif
 
+#ifdef CONFIG_GENERIC_MMC
+       puts ("MMC:   ");
+       mmc_initialize (bd);
+#endif
+
 #ifdef CONFIG_HAS_DATAFLASH
 	AT91F_DataflashInit();
 	dataflash_print_info();
@@ -854,11 +859,6 @@ extern void davinci_eth_set_mac_addr (const u_int8_t *addr);
 	board_late_init ();
 #endif
 
-#ifdef CONFIG_GENERIC_MMC
-	puts ("MMC:   ");
-	mmc_initialize (gd->bd);
-#endif
-
 #ifdef CONFIG_BITBANGMII
 	bb_miiphy_init();
 #endif
diff --git a/common/env_mmc.c b/common/env_mmc.c
index cc288d4..d443ff5 100644
--- a/common/env_mmc.c
+++ b/common/env_mmc.c
@@ -129,18 +129,21 @@ inline int read_env(struct mmc *mmc, unsigned long size,
 void env_relocate_spec(void)
 {
 #if !defined(ENV_IS_EMBEDDED)
+       char buf[CONFIG_ENV_SIZE];
+
 	struct mmc *mmc = find_mmc_device(CONFIG_SYS_MMC_ENV_DEV);
 
-	if (init_mmc_for_env(mmc))
+	if (init_mmc_for_env(mmc)) {
+		use_default();
 		return;
+	}
 
-	if (read_env(mmc, CONFIG_ENV_SIZE, CONFIG_ENV_OFFSET, env_ptr))
-		return use_default();
-
-	if (crc32(0, env_ptr->data, ENV_SIZE) != env_ptr->crc)
-		return use_default();
+	if (read_env(mmc, CONFIG_ENV_SIZE, CONFIG_ENV_OFFSET, buf)) {
+		use_default();
+		return;
+	}
 
-	gd->env_valid = 1;
+	env_import(buf, 1);
 #endif
 }