Plan to support Rockchip VPU in DRM, is it a good idea

From: Randy Li
Date: Thu Aug 25 2016 - 22:22:44 EST

We always use some kind of hack work to make our Video Process Unit(Multi-format Video Encoder/Decoder) work in kernel. From a customize driver(vpu service) to the customize V4L2 driver. The V4L2 subsystem is really not suitable for the stateless Video process or it could make driver too fat.
After talking to some kindness Intel guys and moving our userspace library to VA-API driver, I find the DRM may the good choice for us.
But I don't know whether it is welcome to to submit a video driver in DRM subsystem?
Also our VPU(Video process unit) is not just like the Intel's, we don't have VCS, we based on registers to set the encoder/decoder. I think we may need a lots of IOCTL then. Also we do have a IOMMU in VPU but also not a isolated memory for VPU, I don't know I should use TT memory or GEM memory.
I am actually not a member of the department in charge of VPU, and I am just beginning to learning DRM(thank the help from Intel again), I am not so good at memory part as well(I am more familiar with CMA not the IOMMU way), I may need know guide about the implementations when I am going to submit driver, I hope I could get help from someone.

Randy Li
The third produce department