Re: [hatari-devel] Suspected problem iwith TimerD patch

[Nicolas Pomarède <npomarede@xxxxxxxxxxxx>]

Le 11/12/2020 à 11:49, Eero Tamminen a écrit :

> Ah, I see.
>
> With your change, patching is done every time Timer-D is started, not 
> just on first time:
> https://git.tuxfamily.org/hatari/hatari.git/tree/src/mfp.c?id=v2.2.1#n2063
>
> Attached is same patch for v2.3 (+ removal of
> the old obsolete variable).
>
> However, I don't see any noticeable change from it
> either to Hatari or game perf under EmuTOS. Hatari
> still takes about same amount of CPU, and game
> still takes 8 VBLs to move objects, same as
> earlier, with and without Timer-D patching.

IIRC TOS does set ctrlD=1 only once on boot, which is why 
bAppliedTimerDPatch (<= 2.2) or PatchTimerD_Done (in 2.3) is set once 
and not reset after.

This is a simple heuristic to patch the first (wrong) case where ctrlD 
is set to 1 on boot, but we might not want to patch subsequent changes 
made elsewhere in TOS.

Nicolas