On Mon, Oct 14, 2019 at 09:11:17AM +0000, Brian Starkey wrote:
On Fri, Oct 11, 2019 at 07:25:02PM +0200, Daniel Vetter wrote:
On Fri, Oct 11, 2019 at 12:56 PM Brian Starkey Brian.Starkey@arm.com wrote:
Hi,
On Fri, Oct 11, 2019 at 11:14:43AM +0200, Neil Armstrong wrote:
Hi Brian,
On 11/10/2019 10:41, Brian Starkey wrote:
Are you sure the GPU supports other orders? I think any Arm driver will only be producing DRM_FORMATs with "BGR" order e.g. ABGR888> I'm not convinced the GPU HW actually supports any other order, but it's all rather confusing with texture swizzling. What I can tell you for sure is that it _does_ support BGR order (in DRM naming convention).
Well, since the Bifrost Mali blobs are closed-source and delivered by licensees, it's hard to define what is supported from a closed GPU HW, closed SW implementation to a closed pixel format implementation.
I hear you. IMO the only way to make any of this clear is to publish reference data and tests which make sure implementations match each other. It's something I'm trying to make happen.
*cough* igt test with crc/writeback validation *cough*
And you don't even need anything that actually compresses. All you need is the minimal enough AFBC knowledge to set up the metadata that everything is uncompressed. We're doing that for our intel compression formats already, and it works great in making sure that we have end-to-end agreement on all the bits and ordering and everything.
Yeah this was my original thinking too. Sadly, a decent number of the AFBC parameters can't be tested with uncompressed data, as the codec kicks into a different mode there.
Hm right I guess some of the flags/parameters only matter if you deal with actual compressed data. Still, better than nothing I guess - this should at least catch stuff like color channels wired up the wrong way compared to linear, and fun stuff like that.
Ofc it doesn't validate the decoder, but that's not really igts job. Should be possible to convince ARM to release that (as open source, in igt), since it would be fairly valuable for the entire ecosystem here ...
I fully agree about the value proposition.
I'll be waiting for patch from arm then :-)
Cheers, Daniel