Re: [hatari-devel] EmuTOS + 68040 + GEMDOS drive

[Nicolas Pomarède <npomarede@xxxxxxxxxxxx>]

Le 04/12/2017 à 15:47, Thorsten Otto a écrit :
> BTW there might be another issue, that might be relevant only when using MMU.
> Don't know how exact the cache emulation of Hatari is, but if you configure
> some pages to be WB, then some data might be only valid in the cache, but not
> in memory. In that case, the contents of the cache have to be flushed to
> memory by functions like GEMDOS_Write().

WinUAE cpu emulation supports writeback/copyback mode.
As you say, with the current "simpler" method of flushing everything, 
some cache entries in 68040/60 mode might be lost and corresponding data 
not updated in the related page.

As Toni wrote, a better fine-grained solution would be to simulate a 
call to cpush in that case to invalidate just 1 address.

But I don't know if TOS itself or EmuTos are using WB mode or if they 
default to writethrough ?

That's something to keep on the todo list for later ;)

Nicolas