Block device read operation misses one byte(8 bit) per chip per SPI transaction about qemu

[saipava]

Hi @m1shaikh ,
We have tested the model with plm, u-boot and Linux. Which didn't show above issue.
Can you test the use case over u-boot ?

Also, can you mention which qemu dtb are you using for emulation here?

[m1shaikh]

Did you have more than one Read SPI transaction requests coming in? The issue is only seen if there is more than one SPI transaction for read request.
From code inspection at m25p80_transfer8() of hw/block/m25p80.c, once the state machine is in STATE_READ state, there is no transition to accept new command coming in. This has two effects, first, once the state machine is in STATE_READ state it stays in there indefinitely and second, for the second READ command, first read byte is not returned, resulting in missing byte.

[saipava]

@m1shaikh In case of a dual parallel configuration, both flashes get read command.
It would be helpful in debug, if you mention your complete command line,and which dtb are you using here.