Hello, I noticed an issue with env erase command when environment is stored in a emmc device, in case start/end are not aligned to the emmc erase groups size additional data is erased with just a warning.
``` Erasing Environment on MMC...
Caution! Your devices Erase group is 0x400 The erase range would be change to 0xf800~0xfbff ```
Output from `mmc info`:
``` Device: FSL_SDHC Manufacturer ID: 13 OEM: 14e Name: S0J56 Bus Speed: 200000000 Mode: HS400 (200MHz) Rd Block Len: 512 MMC version 5.1 High Capacity: Yes Capacity: 14.8 GiB Bus Width: 8-bit DDR Erase Group Size: 512 KiB HC WP Group Size: 8 MiB User Capacity: 14.8 GiB WRREL Boot Capacity: 31.5 MiB ENH RPMB Capacity: 4 MiB ENH ```
I do not think that this is the correct behavior, I think that in case the env is not aligned to the erase block size the erase should either fail or fall back to just writing 0xff. Not sure if just changing `mmc_berase()` is going to affect any other use case in which is valid to have a non-aligned start/size and just erase around it after a warning.
Any comment?
Francesco