Re: Linux 6.4.4 on m68k - Q40 - pata_falcon causes oops at boot time

Michael Schmitz
2023-07-29T04:57:06Z

Hi Geert,

Am 28.07.2023 um 20:03 schrieb Geert Uytterhoeven:
> Hi Michael,
>
> On Fri, Jul 28, 2023 at 9:52 AM Michael Schmitz <schmitzmic@gmail.com> wrote:
>> Am 28.07.2023 um 11:47 schrieb Finn Thain:
>>> What I had in mind is probably unacceptable because drivers end up having
>>> to do byteswapping as happens in pata_falcon (or falconide and q40ide).
>>
>> Yes, but Q40 and Falcon are impossible to support any other way, and
>> byte swapping the IDE interface in hardware was never repeated anywhere
>> else, fortunately. We will have to keep pata_falcon around for that
>> cause in any event.
>
> Anyone remember TiVo? PPC with byte-swapped IDE interface.

I vaguely remember, but had forgotten even that it was a PPC machine.

>
>>> It might be helpful to look for some precedent for this kind of thing
>>> among the other big-endian platforms with ISA. MIPS Magnum is dual-endian
>>> but Linux only runs in little-endian mode and the problem doesn't arise.
>>> But there must be other examples. Maybe CHRP?
>>
>> Not all of CHRP, hearing Geert tell it. But there must be some boards
>> that have an ISA bus?
>
> It did have an ISA bus, but no ISA slots.
> But the only external device on that bus was cs4232 audio.

Thanks, I'll take a look at that.

Cheers,

Michael

> All other ISA devices were internal to the south bridge.
> http://g33rt.be/migrated/Linux/PPC/pci/isaAT1/.
>
> Gr{oetje,eeting}s,
>
> Geert
>