Drm: mgag200. Video adapter issue with 5.4.0-rc3 ; no graphics

[John Donnelly]

> On Nov 13, 2019, at 11:42 AM, John Donnelly <john.p.donnelly at oracle.com> wrote:
> 
> Hi Thomas:  See below 
> 
>> On Nov 13, 2019, at 2:17 AM, Thomas Zimmermann <tzimmermann at suse.de> wrote:
>> 
>> Hi John
>> 
>> Am 12.11.19 um 20:13 schrieb John Donnelly:
>>> 
>>> In short .  I started   with :
>>> 
>>> git bisect start 
>>> 
>>> git bisect bad be8454afc50f
>>> 
>>> git bisect good fec88ab0af97
>>> 
>>> And at the  the end of   bisects  showed this was the offending commit :
>>> 
>>> c0a74c732568 
>>> 
>>> commit c0a74c732568ad347f7b3de281922808dab30504 (refs/bisect/bad)
>>> Author: Jani Nikula <jani.nikula at intel.com>
>>> Date:   Fri May 24 20:35:22 2019 +0300
>>> 
>>>   drm/i915: Update DRIVER_DATE to 20190524
>>> 
>>>   Signed-off-by: Jani Nikula <jani.nikula at intel.com>
>>> 
>>> That does not have any real relevance
>> 
>> No, that doesn't look right. The other bad commits you list below also
>> don't seem to be related.
> 
> 
> 
> Thank you for your patience ;  I  started over and the bisect took to me to  this change that certainly reflects the behavior I am seeing :
> 
> commit 81da87f63a1edebcf8cbb811d387e353d9f89c7a (refs/bisect/bad)
> Author: Thomas Zimmermann <tzimmermann at suse.de>
> Date:   Tue May 21 13:08:29 2019 +0200
> 
>    drm: Replace drm_gem_vram_push_to_system() with kunmap + unpin
> 
>    The push-to-system function forces a buffer out of video RAM. This decision
>    should rather be made by the memory manager. By replacing the function with
>    calls to the kunmap and unpin functions, the buffer's memory becomes available,
>    but the buffer remains in VRAM until it's evicted by a pin operation.
> 
>    This patch replaces the remaining instances of drm_gem_vram_push_to_system()
>    in ast and mgag200, and removes the function from DRM.
> 
> 
> My 1st impression is we need a method  that restores the previous behavior that pushes the content to the device .    

It appears  many of the code changes  that were involved in 81da87f63a1 ( above ) have been superseded by :



commit 5d17718997367c435dbe5341a8e270d9b19478d3
Author: Thomas Zimmermann <tzimmermann at suse.de>
Date:   Thu Jun 27 10:09:09 2019 +0200

    drm/mgag200: Replace struct mga_framebuffer with GEM framebuffer helpers

Are there any other methods  (tools ) you could recommend  outside of starting Gnome that I could use to get a display activity  shown on the console ?
    

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