[PATCH v3 4/5] ARM: footbridge: limit CONFIG_ISA to CATS

[Arnd Bergmann]

On Sun, Sep 11, 2022, at 9:53 PM, Russell King (Oracle) wrote:
> On Fri, Sep 09, 2022 at 10:57:48PM +0200, Arnd Bergmann wrote:
>> From: Arnd Bergmann <arnd at arndb.de>
>> 
>> The CONFIG_ISA option is only used for actual add-in cards, not
>> on-board devices. NetWinder has no hardware support for those,
>> and ebsa285 appears to not support them in Linux, as the XBUS
>> is not set up that way and there is no support for a PCI-ISA
>> bridge.
>
> That is an incorrect assumption, but is still true as far as ISA
> DMA is concerned.
>
> The "Team" produced a PCI card with a PCI southbridge chip on, along
> with ISAPNP devices. ISAPNP depends on CONFIG_ISA... That said, using
> the "ESS ES1879 Plug and Play AudioDrive" on it requires ISA DMA, and
> as DMA from the PCI southbridge causes the PCI bus to deadlock, it
> probably doesn't matter.
>
> However, what I'm pointing out is that the assertion that CONFIG_ISA
> means ISA cards is not entirely correct with the creation of this
> PCI southbridge card.
>
> (This card gives me keyboard, mouse, serial etc ports which is its
> main use in the machine.)

I dropped the patch now, and queued the rest of the series for
the 6.1 merge window.

      Arnd