We have a board with several revisions. The older ones use a nor flash with 64k erase size, while the newer have a flash with 4k sectors. The environment size is 8k.
Currently, we have to put a column containing 0x10000 (64k) in fw_env.config in order for it to work on the older boards. But that ends up wasting quite a lot of time on the newer boards that could just erase the 8k occupied by the environment - strace says the 64k erase takes 0.405 seconds. With this patch, as expected, that's about an 8-fold better, at 0.043 seconds.
Having different fw_env.config files for the different revisions is highly impractical, and the correct information is already available right at our fingertips. So use the erasesize returned by the MEMGETINFO ioctl when the fourth and fifth columns (sector size and #sectors, respectively) are absent or contain 0, a case where the logic previously used to use the environment size as erase size (and consequently computed ENVSECTORS(dev) as 1).
As I'm only testing this on a NOR flash, I'm only changing the logic for that case, though I think it should be possible for the other types as well.
Signed-off-by: Rasmus Villemoes rasmus.villemoes@prevas.dk ---
v2: Also require ENVSECTORS(dev) to be absent (or 0) to apply this, in order to prevent regressions in the somewhat odd case where someone used 0 as sector size (and hence used the environment size as sector size) and explicitly listed 1 as #sectors.
tools/env/fw_env.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/tools/env/fw_env.c b/tools/env/fw_env.c index 381739d28d..8734663cd4 100644 --- a/tools/env/fw_env.c +++ b/tools/env/fw_env.c @@ -1647,6 +1647,9 @@ static int check_device_config(int dev) goto err; } DEVTYPE(dev) = mtdinfo.type; + if (DEVESIZE(dev) == 0 && ENVSECTORS(dev) == 0 && + mtdinfo.type == MTD_NORFLASH) + DEVESIZE(dev) = mtdinfo.erasesize; if (DEVESIZE(dev) == 0) /* Assume the erase size is the same as the env-size */ DEVESIZE(dev) = ENVSIZE(dev);