Subject: Re: MachHitFlushDCache() call in vm_machdep.c
To: Toru Nishimura <nisimura@itc.aist-nara.ac.jp>
From: Takao Shinohara <shin@sm.sony.co.jp>
List: port-mips
Date: 06/15/2000 22:07:59
nisimura@itc.aist-nara.ac.jp (Toru Nishimura) writes:
> I'd like to remove the following code segment from vm_machdep.c which
> is shared by all of NetBSD ports.  Unfortunately I have no R4000
> descenders at hand and no chance to check the removal is valid or not.
> Can MIPS3 owers verify the ommision makes no harm or does matter? 
> 
> void
> cpu_fork(p1, p2, stack, stacksize, func, arg)
>         struct proc *p1, *p2;
>         void *stack; 
>         size_t stacksize;
>         void (*func) __P((void *));
>         void *arg;
> {
> 	...
> #ifdef MIPS3
>         /* ? make sense ? */
>         if (CPUISMIPS3)
>                 MachHitFlushDCache((vaddr_t)p2->p_addr, USPACE);
> #endif

This cache operation is necessary for R4000/R4400 with secondary cache.
Do not remove.

--- Takao Shinohara