Commit Graph

4 Commits

Author SHA1 Message Date
Christian Lamparter
ee424f7d39 nvmem: u-boot-env: fix crc32_data_offset on redundant u-boot-env
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>
2022-11-10 18:45:59 +01:00
Rafał Miłecki
3717ca3e0c nvmem: u-boot-env: fix crc32 casting type
This fixes:
drivers/nvmem/u-boot-env.c:141:17: sparse: sparse: cast to restricted __le32

Fixes: d5542923f2 ("nvmem: add driver handling U-Boot environment variables")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20220916122100.170016-14-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-24 14:56:37 +02:00
Rafał Miłecki
d4d432670f nvmem: u-boot-env: find Device Tree nodes for NVMEM cells
DT binding allows specifying NVMEM cells as NVMEM device (provider)
subnodes. Looks for such subnodes when building NVMEM cells.

This allows NVMEM consumers to use U-Boot environment variables.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20220916122100.170016-11-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-24 14:54:38 +02:00
Rafał Miłecki
d5542923f2 nvmem: add driver handling U-Boot environment variables
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>
2022-09-24 14:54:37 +02:00