Re: "Fix ATAPI transfer lengths" causes CD writing regression

Alan Cox
2007-11-01T10:52:28Z

O> Hmmm.... reading ide-cd.c::cdrom_pc_intr(). OIC, ide-cd is dealing with
> this problem by draining PIO after BMDMA engine is done. This is
> possible for BMDMA engines as they simply step out when the SG entries
> are exhausted; then, the interrupt handler kicks in and drains the
> left-over using PIO. This just isn't possible with more modern DMA engines.

Its not possible with old ones either - its a bug not a feature and is
why there is special casing for stuff like promise where this hangs the
chip.

Alan