Questions about libdrm programming

Questions about libdrm programming

[Zachary Catlin]

I'm interested in (1) using my graphics card for computations and
(2) low-level shader code, and I'm looking for guidance on how I would
go about doing the following operations with libdrm (sans Mesa):

* client-side initialization
* loading textures into the GPU
* loading a bytecode shader into the GPU
* creating a texture on the GPU without uploading data
* running the shader using the uploaded textures as inputs and the
  non-uploaded texture as the output
* transferring the output texture into main memory
* tear-down, finalization

The GPU in question is a Radeon RV730, if any hardware-dependent
discussion is needed. I've tried to understand the workflow by looking
at the Mesa and Plymouth sources and the documentation I've found for
the DRI/DRM, but I could still use some guidance.

Re: Questions about libdrm programming

[Dave Airlie]

On Sat, Jun 11, 2011 at 11:03 AM, Zachary Catlin <z@zc.is> wrote:
> I'm interested in (1) using my graphics card for computations and
> (2) low-level shader code, and I'm looking for guidance on how I would
> go about doing the following operations with libdrm (sans Mesa):http://cgit.freedesktop.org/~airlied/radeondemo

Its not something libdrm really does, its only a simple abstraction
around ioctls.

http://cgit.freedesktop.org/~airlied/radeondemo

is a simple layer on top that just does some blits using the shaders
from the DDX.

Dave.

Re: Questions about libdrm programming

[Zachary Catlin]

On Sat, 11 Jun 2011 11:39:39 +1000
Dave Airlie <airlied@gmail.com> wrote:

> Its not something libdrm really does, its only a simple abstraction
> around ioctls.

I'd managed to figure that out--I just figured the abstraction was
there to save a little typing and act as a type-level sanity check.

> http://cgit.freedesktop.org/~airlied/radeondemo
> 
> is a simple layer on top that just does some blits using the shaders
> from the DDX.

This is the sort of thing I tried to find. Thanks!
-- 
Zachary Catlin    z@zc.is
The only way of discovering the limits of the possible is to
venture a little way past them into the impossible.
  --Clarke's Second Law