2012/10/29 Matthijs Kooijman <matthijs@xxxxxxxx>: > I'm using some evergreen systems with HDMI output, which got broken by a > recent commit. In commit 1c3439f (drm/radeon/hdmi: update modesetting), > the HDMI_ACR_SOURCE bit is set in the HDMI_ACR_PACKET_CONTROL register. > > However, setting this bit breaks my HDMI audio when a non-default > resolution is used. This problem only occurs on some TV's (it's broken > on a Philips, Sharp and Sony TV and seems to be working on a few LG > TV's). > > On the Sony, there are short pulses of distorted audio (couple of > hundred ms audio, then half a second or so silence, then some audio > again, etc.). On the Philips and Shart TV's, the audio is completely > muted. > > It seems setting this bit causes the audio infoframe timings to be > controlled by software instead. I suspect that the timings are not > properly (re)calculated when a non-default resolution is used, causing > the audio to break. > > Alex Deucher mentioned on IRC that the proper timing code needs to be > ported over. I might have a look at that, if I can find enough time and > understanding, but that might take a while. Would it make sense to > disable this particular bit for the time being, to make audio working > again? Is there any particular reason to not keep the bit disabled and > let the timings be determined by the hardware in any case? I've (finally) taken a look at fglrx and it also doesn't set that bit: RREG32(0x0001203c); -> 0x00010000 WREG32(0x0001203c, 0x00011000); 0x0001203c = HDMI_ACR_PACKET_CONTROL 0x00011000 = HDMI_ACR_AUTO_SEND | HDMI_ACR_N_MULTIPLE(1) I think maybe we should ignore Alex's code [0] based on (probably) some internal specs and just copy fglrx behavior. I guess the fglrx team discovered some issues with the specs and fixed just the code. [0] http://people.freedesktop.org/~agd5f/0001-WIP-port-of-hdmi-dp-audio-code-to-newer-kernel.patch -- Rafał _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel
