[U-Boot] [PATCH v1] env_mmc: configure environment offsets via device tree

[Philipp Tomsich]

This introduces the ability to override the environment offets from the
device tree by setting the following nodes in '/config':
	'u-boot,mmc-env-offset' - overrides CONFIG_ENV_OFFSET
	'u-boot,mmc-env-offset-redundant'
				- overrides CONFIG_ENV_OFFSET_REDUND

To keep with the previous logic, the CONFIG_* defines still need to
be available and the statically defined values become the defaults,
when the corresponding properties are not set in the device-tree.

Signed-off-by: Philipp Tomsich <philipp.tomsich at theobroma-systems.com>
---
 common/env_mmc.c | 31 +++++++++++++++++++++++++++----
 1 file changed, 27 insertions(+), 4 deletions(-)

diff --git a/common/env_mmc.c b/common/env_mmc.c
index 16f6a17..ef3dbd1 100644
--- a/common/env_mmc.c
+++ b/common/env_mmc.c
@@ -1,24 +1,25 @@
 /*
  * (C) Copyright 2008-2011 Freescale Semiconductor, Inc.
  *
  * SPDX-License-Identifier:	GPL-2.0+
  */
 
 /* #define DEBUG */
 
 #include <common.h>
 
 #include <command.h>
 #include <environment.h>
+#include <fdtdec.h>
 #include <linux/stddef.h>
 #include <malloc.h>
 #include <memalign.h>
 #include <mmc.h>
 #include <search.h>
 #include <errno.h>
 
 #if defined(CONFIG_ENV_SIZE_REDUND) &&  \
 	(CONFIG_ENV_SIZE_REDUND != CONFIG_ENV_SIZE)
 #error CONFIG_ENV_SIZE_REDUND should be the same as CONFIG_ENV_SIZE
 #endif
 
@@ -36,21 +37,43 @@ DECLARE_GLOBAL_DATA_PTR;
 #define CONFIG_ENV_OFFSET 0
 #endif
 
-__weak int mmc_get_env_addr(struct mmc *mmc, int copy, u32 *env_addr)
+#ifdef CONFIG_OF_LIBFDT
+static inline s64 mmc_offset(int copy)
 {
-	s64 offset;
+	const char *propname = "u-boot,mmc-env-offset";
+	s64 defvalue = CONFIG_ENV_OFFSET;
 
-	offset = CONFIG_ENV_OFFSET;
-#ifdef CONFIG_ENV_OFFSET_REDUND
+#if defined(CONFIG_ENV_OFFSET_REDUND)
+	if (copy) {
+		propname = "u-boot,mmc-env-offset-redundant";
+		defvalue = CONFIG_ENV_OFFSET_REDUND;
+	}
+#endif
+
+	return fdtdec_get_config_int(gd->fdt_blob, propname, defvalue);
+}
+#else
+static inline s64 mmc_offset(int copy)
+{
+	s64 offset = CONFIG_ENV_OFFSET;
+
+#if defined(CONFIG_ENV_OFFSET_REDUND)
 	if (copy)
 		offset = CONFIG_ENV_OFFSET_REDUND;
 #endif
+	return offset;
+}
+#endif
+
+__weak int mmc_get_env_addr(struct mmc *mmc, int copy, u32 *env_addr)
+{
+	s64 offset = mmc_offset(copy);
 
 	if (offset < 0)
 		offset += mmc->capacity;
 
 	*env_addr = offset;
 
 	return 0;
 }
 
-- 
1.9.1