Re: [PATCH] drm/radeon: Fix regression with suspend/resume

From: Christian KÃnig
Date: Sun Feb 22 2015 - 05:44:55 EST

On 22.02.2015 00:18, Ross Zwisler wrote:
On Wed, 2015-02-18 at 13:02 +0100, Christian KÃnig wrote:
Well, what the patch does is just changing where buffers are placed in
memory. E.g. now we place the buffer at the end of memory as well.

So I can imagine at least three possible causes for the issues you see:
1. We haven't implemented all buffer placement restrictions correctly
and without the patch everything just works fine by coincident.
2. Something is overwriting the buffer at it's new location.
@Alex&Michel: Didn't we had a similar problem internally recently? Or
was that just for APUs?
3. One of the memory chips on your hardware is faulty and without the
patch the we just don't use the affected region (rather unlikely).

For testing could you try to limit the amount of VRAM used? E.g. give
radeon.vramlimit=256 as kernel commandline to limit the VRAM to the
first 256MB.
Tried with the kernel parameter radeon.vramlimit=256, and it seemed to have
the exact same behavior. The flicker was still there, same size, same

Well how much memory does the card have in the first place? 256MB was just an example.

Please provide a complete dmesg output with that paramater.


- Ross

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