Re: linux cache routines for Write-back cache policy on MIPS24KE

[Geert Uytterhoeven <geert@linux-m68k.org>]

On Mon, 1 Oct 2007, veerasena reddy wrote:
> In linux-2.6.18 (for MIPS24KE processor):
> suppose if i want to do flush only then which API i
> should use?

`flush' is fuzzy terminology: some people mean invalidate, others mean
write back, others mean both.

> Similarly, if i want to do invalidation only which API
> i should use?

dma_cache_inv().

> --- Geert Uytterhoeven <geert@linux-m68k.org> wrote:
> 
> > On Mon, 1 Oct 2007, veerasena reddy wrote:
> > > I have ported Linux-2.6.18 kernel on MIPS24KE
> > > processor. I am using write back cache policy.
> > > 
> > > Could you please guide me under what cases the
> > below
> > > cache API's are being used:
> > > - dma_cache_wback_inv() : Could you explain  what
> > > exactly this function does
> > 
> > It does both write back and invalidate.
> > 
> > > - dma_cache_wback() : This function write back the
> > > cache data to memory
> > > - dma_cache_inv  : This function invalidate the
> > cache
> > > tags. so subsequent access will fetch from memory.
> > 
> > Note that 2.6.18 is old. The above functions are
> > intended to be removed.

Gr{oetje,eeting}s,

						Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
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