[OpenBIOS] r579 - trunk/openbios-devel/modules

[Laurent Vivier]

Le samedi 19 septembre 2009 à 11:37 +0200, Segher Boessenkool a écrit :
> > +#ifdef CONFIG_PPC
> > +		flush_icache_range( addr, addr + size );
> > +#endif
> 
> I'm not sure what your flush_icache_range() does exactly, but at a

It is not mine ;-)

> minimum it is misnamed: you need to flush the dcache for this range
> to memory (dcbst is enough), do a sync, invalidate the icache (icbi),
> do another sync, do an isync.

It does exacly what you explain, see arch/ppc/qemu/start.S:

#define CACHE_LINE_SIZE         32
#define LG_CACHE_LINE_SIZE      5

/* flush_icache_range( ulong start, ulong stop) */
GLOBL(flush_icache_range):
        li      r5,CACHE_LINE_SIZE-1
        andc    r3,r3,r5
        subf    r4,r3,r4
        add     r4,r4,r5
        srwi.   r4,r4,LG_CACHE_LINE_SIZE
        beqlr
        mtctr   r4
        mr      r6,r3
1:      dcbst   0,r3
        addi    r3,r3,CACHE_LINE_SIZE
        bdnz    1b
        sync                            /* wait for dcbst's to get to
ram */
        mtctr   r4
2:      icbi    0,r6
        addi    r6,r6,CACHE_LINE_SIZE
        bdnz    2b
        sync                            /* additional sync needed on g4
*/
        isync
        blr

Regards,
Laurent
-- 
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