Hello Thierry, 09.07.2021 22:31, Thierry Reding пишет: > From: Thierry Reding <treding@xxxxxxxxxx> > > Hi all, > > Mikko has been away for a few weeks, so I've been testing and revising > the new UABI patches in the meantime. There are very minor changes to > the naming of some of the UABI fields, but other than that it's mostly > unchanged from v7. Why you haven't addressed any of the previous review comments? There were some obvious problems in v7 and v8 still has them. > One notable change is that mappings can now be read-only, write-only, > read-write or none of them (rather than just read-only or read-write), > since those combinations are all supported by the IOMMUs and it might > be useful to make some mappings write-only. > > For a full list of changes in v8, see the changelog in patch 6. > > I've also updated the libdrm_tegra library to work against this version > of the UABI. A branch can be found here: > > https://gitlab.freedesktop.org/tagr/drm/-/commits/drm-tegra-uabi-v8 > > That contains helper APIs for the concepts introduced in this series and > shows how they can be used in various tests that can be run for sanity > checking. > > In addition, Mikko has made updates to the following projects, though > they may need to be updated for the minor changes in v8: > > * vaapi-tegra-driver - https://github.com/cyndis/vaapi-tegra-driver > Experimental support for MPEG2 and H264 decoding on T210, T186 > and T194. > > * xf86-video-opentegra - https://github.com/grate-driver/xf86-video-opentegra > X11 userspace acceleration driver for Tegra20, Tegra30, and Tegra114. > > * grate - https://github.com/grate-driver/grate > 3D rendering testbed for Tegra20, Tegra30, and Tegra114 > > I plan on putting this into linux-next soon after v5.14-rc1 so that this > can get some soak time. It should be a bit too early to push it into kernel. The UAPI is not ready because it's missing essential features. We can't call this a 'modern UABI' until it's fully implemented. The design decisions are still questionable because this UAPI is built around the proprietary firmware (and based on UAPI of downstream driver) which doesn't fit well into DRM world. I haven't got all the answers to my previous questions, should I repeat them? UAPI is not the only problem that we have. The performance and stability of the driver are in a very bad shape too. The modern UAPI can't be built on top of the old code. It's clear now that this is a very serious problem that must be addressed along with the UAPI work and I'm getting silence from you guys.
