Re: [PATCH 1/5]: drm: ati_pcigart: Do not access I/O MEM spaceusing pointer derefs.

From: David Miller
Date: Thu Feb 12 2009 - 06:09:41 EST


From: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
Date: Thu, 12 Feb 2009 21:35:59 +1100

> Oh BTW something else to be careful with, though I suppose it's working
> some what by accident right now... when the GART is in the frame buffer
> it gets applied the current fb swapper setting... ouch !
>
> So it might be a good idea, if we're going to use DRM_READ/WRITE32 which
> afaik are readl/writel (ie, swapping) to make sure we at least
> temporarily disable that swapper while whacking the GART.

Cute.

I wonder if this is what is tripping me up.

But, looking more closely, it appears that:

1) The kernel radeon framebuffer driver doesn't mess with
the framebuffer endianness setting.

2) On >= R300 (which my chip is), Xorg leaves it alone too.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/