Broadcom uses U-Boot for a lot of their bcmbca familiy chipsets. They
decided to store U-Boot environment data inside U-Boot partition and to
use a custom header (with "uEnv" magic and env data length).
Add support for Broadcom's specific binding and their custom format.
Ref: 6b0584c19d ("dt-bindings: nvmem: u-boot,env: add Broadcom's variant binding")
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20221118063932.6418-9-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The Western Digital MyBook Live (PowerPC 464/APM82181)
has a set of redundant u-boot-env. Loading up the driver
the following error:
| u_boot_env: Invalid calculated CRC32: 0x4f8f2c86 (expected: 0x98b14514)
| u_boot_env: probe of partition@1e000 failed with error -22
Looking up the userspace libubootenv utilities source [0],
it looks like the "mark" or "flag" is not part of the
crc32 sum... which is unfortunate :(
|static int libuboot_load(struct uboot_ctx *ctx)
|{
|[...]
| if (ctx->redundant) {
| [...]
| offsetdata = offsetof(struct uboot_env_redund, data);
| [...] //-----^^
| }
| usable_envsize = ctx->size - offsetdata;
| buf[0] = malloc(bufsize);
|[...]
| for (i = 0; i < copies; i++) {
| data = (uint8_t *)(buf[i] + offsetdata);
| uint32_t crc;
|
| ret = devread(ctx, i, buf[i]);
| [...]
| crc = *(uint32_t *)(buf[i] + offsetcrc);
| dev->crc = crc32(0, (uint8_t *)data, usable_envsize);
|
[0] https://github.com/sbabic/libubootenv/blob/master/src/uboot_env.c#L951
Fixes: d5542923f2 ("nvmem: add driver handling U-Boot environment variables")
Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
Link: https://lore.kernel.org/r/70a16eae113e08db2390b76e174f4837caa135c3.1667580636.git.chunkeey@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
U-Boot stores its setup as environment variables. It's a list of
key-value pairs stored on flash device with a custom header.
This commit adds an NVMEM driver that:
1. Provides NVMEM access to environment vars binary data
2. Extracts variables as NVMEM cells
Current Linux's NVMEM sysfs API allows reading whole NVMEM data block.
It can be used by user-space tools for reading U-Boot env vars block
without the hassle of finding its location. Parsing will still need to
be re-done there.
Kernel-parsed NVMEM cells can be read however by Linux drivers. This may
be useful for Ethernet drivers for reading device MAC address which is
often stored as U-Boot env variable.
Reviewed-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20220916122100.170016-2-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Rafał Miłecki