Re: [hatari-devel] Blitter bug in STe mode

[Eero Tamminen <oak@xxxxxxxxxxxxxx>]

Hi,

On 6/9/20 12:37 PM, Thorsten Otto wrote:
> On Dienstag, 9. Juni 2020 11:26:30 CEST Nicolas Pomarède wrote:
> > So it's likely there's no program so far that relies on CAS/CAS2 really
> > doing a rmw cycle during the emulation
>
> Andreas Schwab has commited some fixes to the CAS2 emulation some years ago,
> maybe that is used in linux somewhere?

Checking under Linux v5.6 arch/m68k/...

Only places mentioning CAS/CAS2 are in kernel 060
Unimplemented Integer Instruction exception vector #61 handler, and in 
bus_error030():
                } else if (!(mmusr & MMU_I)) {
                        /* probably a 020 cas fault */
                        if (!(ssw & RM) && send_fault_sig(&fp->ptregs) > 0)
                                pr_err("unexpected bus error 
(%#x,%#x)\n", ssw,
                                       mmusr);

Only place using "tas" I found under was in kernel/head.S serial_init() 
code for Q40.


But maybe they could be used by user-space code?


	- Eero