Re: [PATCH 2.5.13 IDE 54

[Paul Mackerras]

Martin Dalecki writes:

> Sun May  5 16:32:22 CEST 2002 ide-clean-54
> 
> - Finish the changes from patch 53. ide_dma_actaion_t is gone now as well as
>    whole hidden code paths associated with it. I hope I didn't mess too many
>    things up with this, since the sheer size of the changes make them sensitive.

I'm wondering how you would suggest that I change ide-pmac.c now so
that it compiles and works again.

With this patch we have calls to udma_enable scattered throughout
ide.c, and udma_enable assumes that it is to do its stuff by poking
particular I/O ports.  You seem to have taken away the ability to have
a chipset provide its own methods for setting up, enabling and
disabling DMA.

The comment above udma_enable seems to indicate that you think it
should be ifdef'd per-architecture.  That won't work for us (besides
being ugly), because we can have two ATA host adaptors in the one
machine that need to be programmed quite differently.  Consider for
instance a powermac with the built-in IDE interface (which would use
the ide-pmac.c code) and a plug-in PCI IDE card, for which the
udma_enable code is presumably correct.

So we definitely need to have the DMA setup/enable/disable methods
able to be specified per host adaptor.

If I have missed something, please let me know.  But it looks to me
very much as though this patch makes it impossible for me to use my
powermac IDE interfaces.

Paul.