mirror of
https://github.com/brain-hackers/u-boot-brain
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![]() With current implementation of fw_setenv, it is always locks u-boot-env region if lock interface is implemented for such mtd device. You can not control lock of this region with fw_setenv, there is no option for it in config or in application itself. Because of this situation may happen problems like in this thread on xilinx forum: https://forums.xilinx.com/t5/Embedded-Linux/Flash-be-locked-after-use-fw-setenv-from-user-space /td-p/1027851 A short summary of that link is: some person has issue with some spi chip which has lock interface but doesn't locks properly which leads to lock of whole flash memory on lock of u-boot-env region. As resulted solution hack was added into spi-nor.c driver for this chip with lock disablement. Instead fix this problem by adding logic to fw_setenv only lock the flash if it was already locked when we attempted to use it. Signed-off-by: Ivan Mikhaylov <fr0st61te@gmail.com> |
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.. | ||
.gitignore | ||
crc32.c | ||
ctype.c | ||
env_attr.c | ||
env_flags.c | ||
fw_env_main.c | ||
fw_env_private.h | ||
fw_env.c | ||
fw_env.config | ||
fw_env.h | ||
linux_string.c | ||
Makefile | ||
README |
This is a demo implementation of a Linux command line tool to access the U-Boot's environment variables. In order to cross-compile fw_printenv, run make CROSS_COMPILE=<your cross-compiler prefix> envtools in the root directory of the U-Boot distribution. For example, make CROSS_COMPILE=arm-linux- envtools You should then create a symlink from fw_setenv to fw_printenv. They use the same program and its function depends on its basename. For the run-time utility configuration uncomment the line #define CONFIG_FILE "/etc/fw_env.config" in fw_env.h. For building against older versions of the MTD headers (meaning before v2.6.8-rc1) it is required to pass the argument "MTD_VERSION=old" to make. See comments in the fw_env.config file for definitions for the particular board. Configuration can also be done via #defines in the fw_env.h file. The following lines are relevant: #define HAVE_REDUND /* For systems with 2 env sectors */ #define DEVICE1_NAME "/dev/mtd1" #define DEVICE2_NAME "/dev/mtd2" #define DEVICE1_OFFSET 0x0000 #define ENV1_SIZE 0x4000 #define DEVICE1_ESIZE 0x4000 #define DEVICE1_ENVSECTORS 2 #define DEVICE2_OFFSET 0x0000 #define ENV2_SIZE 0x4000 #define DEVICE2_ESIZE 0x4000 #define DEVICE2_ENVSECTORS 2 Un-define HAVE_REDUND, if you want to use the utilities on a system that does not have support for redundant environment enabled. If HAVE_REDUND is undefined, DEVICE2_NAME is ignored, as is ENV2_SIZE and DEVICE2_ESIZE. The DEVICEx_NAME constants define which MTD character devices are to be used to access the environment. The DEVICEx_OFFSET constants define the environment offset within the MTD character device. ENVx_SIZE defines the size in bytes taken by the environment, which may be less then flash sector size, if the environment takes less then 1 sector. DEVICEx_ESIZE defines the size of the first sector in the flash partition where the environment resides. DEVICEx_ENVSECTORS defines the number of sectors that may be used for this environment instance. On NAND this is used to limit the range within which bad blocks are skipped, on NOR it is not used. To prevent losing changes to the environment and to prevent confusing the MTD drivers, a lock file at /var/lock/fw_printenv.lock is used to serialize access to the environment.