Eric Anholt Makes Progress With Broadcom VC4 Graphics Driver

[phoronix]

Phoronix: Eric Anholt Makes Progress With Broadcom VC4 Graphics Driver

One month ago Linux developer Eric Anholt left Intel to work at Broadcom. Eric, a long-time contributor to the open-source Linux graphics stack, is now tasked at Broadcom with developing a DRM driver and Mesa/Gallium3D driver for Broadcom's "VC4" graphics hardware, which is found within the Raspberry Pi...

http://www.phoronix.com/vr.php?view=MTc0Nzc

[Veerappan]

Good to hear. I'll be keeping an eye on this driver, as I've got a Pi on a way for use as a debian-based print server and probably as a random client to dump light background workloads onto.

If it works well, I may buy another one for use as a playback-only HTPC/XBMC machine that I can stick upstairs.

[monkeynut]

Does this mean full OpenGL could come to the Pi as well as OpenGL ES? Or is that a limitation of the hardware?

[plonoma]

The Raspberri Pi hardware only supports OpenGL ES 1/2.

From: http://elinux.org/Raspberry_Pi_VideoCore_APIs

The Raspberry Pi contains a Broadcom VideoCore IV GPU providing OpenGL ES 1.1, OpenGL ES 2.0, hardware-accelerated OpenVG 1.1, Open EGL, OpenMAX and 1080p30 H.264 high-profile decode. There are 24 GFLOPS of general purpose compute and a bunch of texture filtering and DMA infrastructure. Eben worked on the architecture team for this and the Raspberry Pi team are looking at how they can make some of the proprietary features available to application programmers.

[monkeynut]

That's a shame. It would save a lot of development time for OSS games. Still, would this allow us to play windowed games like we do on the PC? Last time I tried using OGL on the Pi I had to do things from the command line.

[Azrael5]

That's a shame. It would save a lot of development time for OSS games. Still, would this allow us to play windowed games like we do on the PC? Last time I tried using OGL on the Pi I had to do things from the command line.

opengl 2.0 is not good?

[robclark]

Does this mean full OpenGL could come to the Pi as well as OpenGL ES? Or is that a limitation of the hardware?

anholt would know better, but I suspect it should be able to support and emulate enough GL to be useful.. adreno is only GLES hw, but a2xx could do enough for a GL 1.4 context, and a3xx enough for GL 2.0. Maybe not enough for compliance but enough that xbmc, some games, etc, work. No idea if that is really a priority for him or not.. I suspect at the moment dealing with all the challenges as for as shader/texture validation is enough to keep him busy.

[libv]

Does this hardware not have a 2D engine somewhere?

[monkeynut]

anholt would know better, but I suspect it should be able to support and emulate enough GL to be useful.. adreno is only GLES hw, but a2xx could do enough for a GL 1.4 context, and a3xx enough for GL 2.0. Maybe not enough for compliance but enough that xbmc, some games, etc, work. No idea if that is really a priority for him or not.. I suspect at the moment dealing with all the challenges as for as shader/texture validation is enough to keep him busy.

I understand. I was under the impression the VideoCore 4 was particularly flexible & fast. I've just ordered a Model B+ Pi so hopefully I can make use of this driver. A lot of existing games (OpenMW, VDrift, etc) don't seem to have properly functioning OpenGL ES implementations and so a native one would be useful. Like I say though, starting 3D stuff from the command line is a no-go and we're restricted until Weston comes along.

[Lederhosen]

OpenGL ES 2.0

videocore IV supports OpenGL ES2.0 which is somewhere between OpenGL (not ES) 2.0 and 3.1.

Borrowing from Wikipedia (yeah, I'm lazy..)

http://en.wikipedia.org/wiki/OpenGL_ES

It is based roughly on OpenGL 2.0, but it eliminates most of the fixed-function rendering pipeline in favor of a programmable one in a move similar to transition from OpenGL 3.0 to 3.1.