Re: [hatari-devel] SCU/VME register access?

[Nicolas Pomarède <npomarede@xxxxxxxxxxxx>]

Le 08/04/2020 à 21:01, Christian Zietz a écrit :
> Eero Tamminen schrieb:
>
> > > MFP & SCC interrupts are enabled in VME mask:
> > > https://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k.git/tree/arch/m68k/atari/ataints.c#n303
>
> On real hardware, this is indeed important. Even interrupts *not*
> originating from the VME bus are routed through the SCU. If you mask
> them there, they're not registered by the system anymore. See this issue
> we had a long time ago in EmuTOS where SCC drivers would not see any SCC
> interrupts because EmuTOS didn't enable them in the SCU:
> https://sourceforge.net/p/emutos/mailman/message/36421899/
>
> Whether it's worth emulating that masking in Hatari, I don't know.

Hi

it's true that VME/SCU are adding another "layer" of interrupt to usual 
ST. For now, it's only required when plugging external board, which we 
don't emulate that much.

It should be done someday, but in case I would be the one doing it, it's 
not at the top of my list for now :) Else, others are free to add 
support for the whole bus.

Nicolas