Re: O2 framebuffer problems with install kernel

I reverted the previous patch and applied this one. It works.

Thanks.

On Jul 28, 2008, at 6:42 PM, Izumi Tsutsui wrote:

> [email protected] wrote:
>
>>>> Anyway, it looks just a simple DMA-cache issue and
>>>> the attached patch seems to fix it.
>>> [snip]
>>>
>>> Yes, that gets it working. Excellent!
>>
>> Same here. What are the implications of that patch? Is that The Right
>> Thing?
>
> As noted in bus_dma(9) BUS_DMA_COHERENT may map DMA memory into
> KSEG1 on mips (which is uncached region), but "The Right Thing" is
> to add a bus_dmamap_sync(9) call rather than BUS_DMA_COHERENT which is
> "just a hint" as described in the MI API.
> ---
> Izumi Tsutsui
>
>
> Index: dev/crmfb.c
> ===================================================================
> RCS file: /cvsroot/src/sys/arch/sgimips/dev/crmfb.c,v
> retrieving revision 1.25
> diff -u -r1.25 crmfb.c
> --- dev/crmfb.c	8 May 2008 02:10:59 -0000	1.25
> +++ dev/crmfb.c	28 Jul 2008 16:35:51 -0000
> @@ -304,6 +304,8 @@
>  	for (i = 0; i < (sc->sc_tiles_x * sc->sc_tiles_y); i++) {
>  		p[i] = ((uint32_t)v >> 16) + i;
>  	}
> +	bus_dmamap_sync(sc->sc_dmat, sc->sc_dmai.map, 0, sc->sc_dmai.size,
> +	    BUS_DMASYNC_PREWRITE);
>  	sc->sc_scratch = (char *)KERNADDR(sc->sc_dma) + (0xf0000 * sc- 
> >sc_tiles_x);
>  	sc->sc_linear = (paddr_t)DMAADDR(sc->sc_dma) + 0x100000 * sc- 
> >sc_tiles_x;
>