Bug in 68k hardware interrupt stack code

[joel at oarcorp.com (joel at oarcorp.com)]

Merged.  Plus Ralf's suggestion not to define CONFIG.$(TARGET_ARCH).CC.

--joel

On Tue, 29 Sep 1998, Eric Norum wrote:

> I found that my 68040/68360 test programs would not run even after I  
> fixed the `wrong BSP' problem.
> 
> It seems that there's a bug in the interrupt handling code for  
> processors with hardware interrupt stacks (e.g. 68040).  The wrong  
> status register was getting pushed on the stack for the `return from  
> exception' to call _ISR__Dispatch.  This ended up making the context  
> switch code run on the interrupt stack, so interrupt-driven context  
> switches would always fail.
> 
> I guess that no one has tried running any of the RTEMS-4.0 snapshots  
> on a 68040 machine!
> 
> Anyhow, here are the patches for
> 1) gen68360.cfg   ---   to fix the `wrong-BSP' problem.
> 2) m68k/cpu_asm.s ---   to fix the hardware interrupt stack problem.
> 
> With these patches in place, the network demo programs run on my  
> 68040/68360 system.  The paranoia program runs with no failures,  
> defects nor flaws.
> 
> [An attachment was originally included here]
> 
> ---
> Eric Norum                                 eric at skatter.usask.ca
> Saskatchewan Accelerator Laboratory        Phone: (306) 966-6308
> University of Saskatchewan                 FAX:   (306) 966-6058
> Saskatoon, Canada.
>