env_mmc.c: Allow environment to be used within SPL

Inside of SPL we only concern ourself with one MMC device, so instead of
being able to use CONFIG_SYS_MMC_ENV_DEV we need to use 0 in SPL.
Switch the code to use a 'dev' variable to facilitate this.

Signed-off-by: Tom Rini <trini@ti.com>

common/env_mmc.c

@@ -64,6 +64,14 @@ int env_init(void)
 
 static int init_mmc_for_env(struct mmc *mmc)
 {
+#ifdef CONFIG_SYS_MMC_ENV_PART
+	int dev = CONFIG_SYS_MMC_ENV_DEV;
+
+#ifdef CONFIG_SPL_BUILD
+	dev = 0;
+#endif
+#endif
+
 	if (!mmc) {
 		puts("No MMC card found\n");
 		return -1;
@@ -76,8 +84,7 @@ static int init_mmc_for_env(struct mmc *mmc)
 
 #ifdef CONFIG_SYS_MMC_ENV_PART
 	if (CONFIG_SYS_MMC_ENV_PART != mmc->part_num) {
-		if (mmc_switch_part(CONFIG_SYS_MMC_ENV_DEV,
-				    CONFIG_SYS_MMC_ENV_PART)) {
+		if (mmc_switch_part(dev, CONFIG_SYS_MMC_ENV_PART)) {
 			puts("MMC partition switch failed\n");
 			return -1;
 		}
@@ -90,9 +97,13 @@ static int init_mmc_for_env(struct mmc *mmc)
 static void fini_mmc_for_env(struct mmc *mmc)
 {
 #ifdef CONFIG_SYS_MMC_ENV_PART
+	int dev = CONFIG_SYS_MMC_ENV_DEV;
+
+#ifdef CONFIG_SPL_BUILD
+	dev = 0;
+#endif
 	if (CONFIG_SYS_MMC_ENV_PART != mmc->part_num)
-		mmc_switch_part(CONFIG_SYS_MMC_ENV_DEV,
-				mmc->part_num);
+		mmc_switch_part(dev, mmc->part_num);
 #endif
 }
 
@@ -174,12 +185,16 @@ static inline int read_env(struct mmc *mmc, unsigned long size,
 			   unsigned long offset, const void *buffer)
 {
 	uint blk_start, blk_cnt, n;
+	int dev = CONFIG_SYS_MMC_ENV_DEV;
+
+#ifdef CONFIG_SPL_BUILD
+	dev = 0;
+#endif
 
 	blk_start	= ALIGN(offset, mmc->read_bl_len) / mmc->read_bl_len;
 	blk_cnt		= ALIGN(size, mmc->read_bl_len) / mmc->read_bl_len;
 
-	n = mmc->block_dev.block_read(CONFIG_SYS_MMC_ENV_DEV, blk_start,
-					blk_cnt, (uchar *)buffer);
+	n = mmc->block_dev.block_read(dev, blk_start, blk_cnt, (uchar *)buffer);
 
 	return (n == blk_cnt) ? 0 : -1;
 }
@@ -188,16 +203,23 @@ static inline int read_env(struct mmc *mmc, unsigned long size,
 void env_relocate_spec(void)
 {
 #if !defined(ENV_IS_EMBEDDED)
-	struct mmc *mmc = find_mmc_device(CONFIG_SYS_MMC_ENV_DEV);
+	struct mmc *mmc;
 	u32 offset1, offset2;
 	int read1_fail = 0, read2_fail = 0;
 	int crc1_ok = 0, crc2_ok = 0;
 	env_t *ep;
 	int ret;
+	int dev = CONFIG_SYS_MMC_ENV_DEV;
 
 	ALLOC_CACHE_ALIGN_BUFFER(env_t, tmp_env1, 1);
 	ALLOC_CACHE_ALIGN_BUFFER(env_t, tmp_env2, 1);
 
+#ifdef CONFIG_SPL_BUILD
+	dev = 0;
+#endif
+
+	mmc = find_mmc_device(dev);
+
 	if (tmp_env1 == NULL || tmp_env2 == NULL) {
 		puts("Can't allocate buffers for environment\n");
 		ret = 1;
@@ -274,9 +296,16 @@ void env_relocate_spec(void)
 {
 #if !defined(ENV_IS_EMBEDDED)
 	ALLOC_CACHE_ALIGN_BUFFER(char, buf, CONFIG_ENV_SIZE);
-	struct mmc *mmc = find_mmc_device(CONFIG_SYS_MMC_ENV_DEV);
+	struct mmc *mmc;
 	u32 offset;
 	int ret;
+	int dev = CONFIG_SYS_MMC_ENV_DEV;
+
+#ifdef CONFIG_SPL_BUILD
+	dev = 0;
+#endif
+
+	mmc = find_mmc_device(dev);
 
 	if (init_mmc_for_env(mmc)) {
 		ret = 1;