Broadcom VC4 Work Well Underway On DRM, Gallium3D Support Planned

Beginning this week, Eric Anholt is now working for Broadcom after working for Intel's Open-Source Technology Center the past several years on the Intel Linux graphics driver stack. While Eric just started there, he's already made some headway on a Broadcom DRM driver and expects to begin developing a Gallium3D driver soon.

Eric has a bare-bones DRM driver under development for the Broadcom VC4 hardware found within the Raspberry Pi. This DRM driver code is based upon the Broadcom 2708 Android driver port with early open-source 3D work done by Simon Hall and now picked up by Eric. Eric's DRM driver in its current form just talks with Broadcom's firmware blob for handling mode-setting and he's just beginning to work on the GPU execution support.

In a few days Eric anticipates starting on the user-space support, for which he's initially targeting a Gallium3D-based driver. He's aiming to do a Gallium3D driver since it's the easiest path to get going for a open-source 3D Linux OpenGL (GLES) driver while later on he might switch the driver model over to being a classic DRI driver in Mesa.

Eric wrote, "I'm probably going to start out doing a gallium driver for simplicity, to avoid having to do all the DRI crap we've got in brw_context.c and texture miptree validation and getting user data into VBOs and all that other almost-boilerplate. Long term I may end up switching to classic so I can get swrast fallbacks and the ability to implement single-copy manually-tiled TexImage uploads like. For now I want to get to drawing triangles as soon as I can."

At Phoronix we covered Eric's departure from Intel for Broadcom earlier in the week while a few hours ago he just posted about his Broadcom VC4 DRM/Gallium3D work to the Mesa-dev mailing list. Eric's far from complete DRM driver for the Broadcom hardware can be tracked via his VC4 Linux kernel branch.