11:56 <q4a> Hi. Does panfrost support GL_EXT_texture_compression_s3tc?

12:34 <CounterPillow> q4a: yes

12:37 <q4a> CounterPillow: is there hardware limitations? I'm using 32bit rk3288 (Mali-T760 MP4) and has empty output in "glxinfo | grep s3tc"

12:38 <q4a> Tested with mesa 21.2.6 and 22.1.5

12:52 <CounterPillow> all I know is that it's there for me on a G52

12:56 <q4a> ok, thanks anyway

12:58 <robmur01> a lot of the compressed texture formats depend on the SoC vendor to enable them in HW, since it's their responsibility to sort out licensing

12:59 <robmur01> and that can vary even with a SoC family, e.g. RK3288W supports more formats than original RK3288

13:11 <q4a> I found in old logs: https://freenode.irclog.whitequark.org/panfrost/2020-08-18

13:11 <q4a> - does panfrost support S3TC textures? - yes, if your device supports it. rk3399 does, rk3288 does not

13:12 <CounterPillow> I assume everything since the patent's expiry will support it

13:19 <q4a> patent expiry was in october 2017, but rk3288 was released in 2014

13:27 <alyssa> q4a: It's indeed up to the SoC integrator to enable.

13:28 <alyssa> Originally that's for licensing reasons, but even with the patents expired I suppose some vendors will fail to enable the exts that are virtually unused on Android

13:28 <alyssa> (where ASTC and ETC are the popular alternatives that all? Mali has supported since T760)

13:28 <alyssa> (and maybe older, I forget off hand)

13:30 <q4a> thanks, is it possible to figure out, if SoC support GL_EXT_texture_compression_s3tc before buying new one?

13:31 <q4a> I would like to by rk3588 with Mali-G610 MP4

13:31 <q4a> *buy

13:40 <alyssa> q4a: Mali-G610 doesn't have upstream Panfrost support yet, so s3tc isn't your bottleneck there!

13:40 <alyssa> We're Working On It(TM)

13:42 <alyssa> The challenge with Mali-G610 (and anything newer) is that the job submission hardware is completely new.

13:42 <alyssa> Previous Mali had, like, 3 registers that the kernel wrote to and that was that :p

13:42 <alyssa> All fixed-function

13:43 <q4a> Ok, I'm understanding that and I'm very thankful for your work. But currently I'm talking about GL_EXT_texture_compression_s3tc hardware support in rk3588.

13:44 <alyssa> The newer Malis ("Mali-Gxyz") replace that with a cortex-m7, a big firmware blob, a microcontroller for a bespoke new instruction set, and a few other shinies.

13:44 <alyssa> more or less requiring a rewrite of the panfrost kernel

13:45 <alyssa> q4a: The Arm DDK is not supported here, please contact your SoC vendor (or Arm) for assistance with their driver, thank you :-)

13:45 <q4a> Thanks, I'll send them email.

13:47 <alyssa> 👍

18:36 <cphealy> robmur01: from the above discussion regarding S3TC, I'm not fully understanding what is being said here. Is it a config option that the SoC vendor must make when selecting the GPU to use which compressed textures will be enabled or not in HW? Can the same GPU model have different compressed textures supported, and if so, how does one determine which are supported on a particular SoC or not?

18:40 <robmur01> see DRM_PANFROST_PARAM_TEXTURE_FEATURES0 - there are a set of configuration signals which need to be tied off (or externally driven) at RTL integration time to enable/disable the offending formats

18:49 <cphealy> tnx robmur01