[Libva] invoking intel vaapi without video out on motherboard

[ykzhao]

On Thu, 2013-05-09 at 11:15 -0600, Matt Pekar wrote:
> Yakui what requirements exist for the motherboard and graphics
> configuration for running DRM?  We're trying to use Intel processors
> for h264 video encoding in a headless setup.  We have everything
> working fine in our desktop X environment, but moving to headless mode
> is proving tricky. 
> 
In order to run the encoding function of intel-vaapi driver, it has the
following requirements for hardware/software.

a. Hardware:
	Assure that your machine should be sandybridge or ivybridge. Please
check your machine.

b. Software:
   Linux kernel: suggest that you use the 3.6/3.8 stable kernel. At the
same time the drivers/gpu/drm/i915 driver should be compiled and
installed. After the i915 kernel driver is loaded, the /dev/dri/card0
will appear.
   libva/intel-vaapi: suggest that the latest staging branch of
libva/intel-vaapi is installed. The libva test case can show you how to
use the DRM for encoding.

Thanks.
   Yakui
   
> 
> My impression is that this would be the standard:
> * motheboard with a video output (in order to create /dev/dri/card0)
> 
> * intel CPU with integrated graphics
> * i965 drivers installed to linux
> 
> 
> Whereas this case would not be possible:
> * motherboard with no video output
> * intel CPU with integrated graphics
> 
> * i965 drivers can't be installed because there's no output to
> reference?
> 
> * discrete graphics card (ati or nvidia) -- creates /dev/dri/card0 but
> of the wrong type
> 
> 
> And this would also not be possible:
> *motherboard with no video output, but booted in headless mode
> * intel CPU with integrated graphics
> 
> *i965 drivers are installed, but because no video output is
> present, /dev/dri/card0 cannot be created
> 
> 
> What sort of hardware/software setups are people successfully using
> DRM in?  We have a mishmash of configurations we're trying, but are
> still learning the connections between X server, DRM, VAAPI, and the
> hardware .
> 
> 
> On Thu, May 9, 2013 at 12:41 AM, ykzhao <yakui.zhao at intel.com> wrote:
>         On Wed, 2013-05-08 at 16:27 -0600, Matt Pekar wrote:
>         > Is it possible to take an intel CPU, motheboard w/out video
>         output,
>         > and use VAAPI through it?
>         >
>         >
>         > I'm trying to use a custom xorg.conf along these lines:
>         >
>         >
>         > Section "Device"
>         >         Identifier "intel0"
>         >         Driver "intel"
>         > EndSection
>         >
>         >
>         > Section "Screen"
>         >         Identifier "screen0"
>         >         Device "intel0"
>         >
>         > EndSection
>         >
>         >
>         > But I'm unable to start X with this:
>         >
>         >
>         > [  5507.348] (II) intel: Driver for Intel Integrated
>         Graphics
>         > Chipsets: i810,
>         > i810-dc100, i810e, i815, i830M, 845G, 854, 852GM/855GM,
>         865G, 915G,
>         > E7221 (i915), 915GM, 945G, 945GM, 945GME, Pineview GM,
>         Pineview G,
>         > 965G, G35, 965Q, 946GZ, 965GM, 965GME/GLE, G33, Q35, Q33,
>         GM45,
>         > 4 Series, G45/G43, Q45/Q43, G41, B43, B43, Clarkdale,
>         Arrandale,
>         > Sandybridge Desktop (GT1), Sandybridge Desktop (GT2),
>         > Sandybridge Desktop (GT2+), Sandybridge Mobile (GT1),
>         > Sandybridge Mobile (GT2), Sandybridge Mobile (GT2+),
>         > Sandybridge Server, Ivybridge Mobile (GT1), Ivybridge Mobile
>         (GT2),
>         > Ivybridge Desktop (GT1), Ivybridge Desktop (GT2), Ivybridge
>         Server,
>         > Ivybridge Server (GT2)
>         > [  5507.348] (--) using VT number 7
>         >
>         >
>         > [  5507.353] (EE) No devices detected.
>         > [  5507.353]
>         > Fatal server error:
>         > [  5507.353] no screens found
>         > [  5507.354]
>         >
>         >
>         > Does X check that there is a physical video out on the
>         motherboard for
>         > it to load a device?  Has anyone been able to use X and
>         VAAPI in this
>         > sort of headless mode?  Would a better approach be to ditch
>         X entirely
>         > and use VAAPI through DRM?
>         
>         
>         The current libva/intel-vaapi driver can be used even when the
>         X is not
>         started.
>         
>         For example: vainfo/avcenc can work without X.
>         
>         You can see the corresponding test case of libva about how to
>         use vaapi
>         under DRM mode.
>         
>         thanks.
>         
>         
>         
>         
>         >
>         >
>         >
>         
>         
> 
>