Re: [hatari-devel] Data cache Issues?

[Nicolas Pomarède <npomarede@xxxxxxxxxxxx>]

Le 29/06/2015 23:28, Eero Tamminen a écrit :
> Hi,
>
> On maanantai 29 kesäkuu 2015, Nicolas Pomarède wrote:
> > Regarding chainz and jewelz, the problem was related to the blitter :
> > during the init, the game moves some blocks of data using the blitter
> > (can't say what kind of data it is) and it reads data near the end of
> > the RAM to copy it elsewhere.
> > The problem is that the code seems buggy, because it starts to read in
> > the RAM, then it reads beyond the RAM in the region that should give a
> > bus error :(
> > So, with 4 MB RAM, it will read $400000,$400002, ...
>
> They need 14MB.

No, see the readme for chainz and jewelz, they need 4 MB (I don't see 
what could require 14 MB here, it's rather simple games).
The fact is that if you use 14 MB, then this will use the region from 
$400000 to $e00000, which is where bus error should happen.
If more than 4 MB ram is used, then there's no more bus error region to 
make the game crashes, but it's still bugged nevertheless, you just 
don't see it.


> > I confirm this work with old cpu core, so I
> > think that something was broken when I updated the code to integrate DSP
> > interrupt into recent WinUAE core (which uses a slightly different code
> > path)
>
> Would it help if I try to bisect it?

Not necessarily, I see what kind of changes I made to handle level 6 DSP 
interrupt, so I can find this "by hand"

> > I will have a look, having a working case will help fixing this.
>
> I noticed you had added one DSP specific fix, but these 3 still freeze.

Was another bug with WinUAE cpu core, but not directly related to the 
changed part about DSP interrupt, so freeze is still there.

> > Didn't have a look to the other cases for now.
>
> IMHO Corsair is most interesting of the rest because data cache is
> what breaks it.
>
> If needed, I can send you my version.

When I run it, I don't see any "data mismatch" log, so it's a different 
case. Do you see those logs with your version ?


Nicolas