Hi Heinrich,
On Fri, 31 Mar 2023 at 04:28, Heinrich Schuchardt xypron.glpk@gmx.de wrote:
On 3/31/23 00:55, Heinrich Schuchardt wrote:
Am 30. März 2023 23:32:22 MESZ schrieb Simon Glass sjg@chromium.org:
At present it is not possible to read from some CDROM drives since the FAT sector size does not match the media's block size. Add a conversion option for this, so that reading is possible.
This does increase SPL size for read-only FAT support by 25 bytes but all but 6 are covered by the previous patch. We could reduce the overhead of this feature to 0 bytes by making the code uglier (using a static variable).
512 and 2048 are not the only physical sector sizes. Some hard drives use 4096.
To complete the logic you have first to take into account the size of a FAT sector (BPB_BytsPerSec) defined in the FAT boot sector which can take values 512, 1024, 2048, or 4096.
Cf. https://academy.cba.mit.edu/classes/networking_communications/SD/FAT.pdf
Best regards
Heinrich
This change deserves a test case.
If we keep this I should be able to add something simple.
Regards, Simon