[PATCH v2 1/3] mx6sabresd: Fix U-Boot corruption after saving the environment

[Fabio Estevam <festevam@gmail.com>]

From: Fabio Estevam <festevam@denx.de>

U-Boot binary has grown in such a way that it goes beyond the reserved
area for the environment variables.
    
Running "saveenv" and rebooting the board causes U-Boot to hang because
of this overlap.
    
Fix this problem by selecting CONFIG_LTO so that the U-Boot proper
size can be reduced.
    
Also, to prevent this same problem to happen in the future, use
CONFIG_BOARD_SIZE_LIMIT, which can detect the overlap in build-time.
    
CONFIG_BOARD_SIZE_LIMIT is calculated as follows:

CONFIG_BOARD_SIZE_LIMIT = CONFIG_ENV_OFFSET - u-boot-img.dtb offset
CONFIG_BOARD_SIZE_LIMIT = 0xc000 - 69 * 1024
CONFIG_BOARD_SIZE_LIMIT = 715766

Signed-off-by: Fabio Estevam <festevam@denx.de>
---
Changes since v1:
- Select LTO. (Tom)

 configs/mx6sabresd_defconfig | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/configs/mx6sabresd_defconfig b/configs/mx6sabresd_defconfig
index a90efe4a7786..d4fb55622cf1 100644
--- a/configs/mx6sabresd_defconfig
+++ b/configs/mx6sabresd_defconfig
@@ -21,6 +21,9 @@ CONFIG_SPL_SERIAL=y
 CONFIG_SPL=y
 CONFIG_SPL_LIBDISK_SUPPORT=y
 CONFIG_PCI=y
+CONFIG_LTO=y
+CONFIG_HAS_BOARD_SIZE_LIMIT=y
+CONFIG_BOARD_SIZE_LIMIT=715766
 CONFIG_FIT=y
 CONFIG_SPL_FIT_PRINT=y
 CONFIG_SPL_LOAD_FIT=y
-- 
2.34.1