On Thu, 14 Oct 2021 09:26:27 +0100 Srinivas Kandagatla srinivas.kandagatla@linaro.org wrote:
On 14/10/2021 00:20, Marek Behún wrote:
Add device tree bindings for U-Boot environment NVMEM provider.
U-Boot environment can be stored at a specific offset of a MTD device, EEPROM, MMC, NAND or SATA device, on an UBI volume, or in a file on a filesystem.
The environment can contain information such as device's MAC address, which should be used by the ethernet controller node.
Have you looked at ./Documentation/devicetree/bindings/mtd/partitions/nvmem-cells.yaml ?
Hello srini,
yes, I have. What about it? :)
That binding won't work for u-boot-env, because the data are stored in a different way. A cell does not have a constant predetermined offset on the MTD. The variables are stored as a sequence of values of format "name=value", separated by '\0's, for example: board=turris_mox\0ethaddr=00:11:22:33:44:55\0bootcmd=run distro_bootcmd\0.... Chaning lengths of values of variables, or deleting variables, moves the data around. Integers and MAC addresses are stored as strings, and so on.
Also the mtd/partitions/nvmem-cells.yaml doesn't take into account u-boot-env stored on non-MTD devices.
Marek