[PATCH v11 00/74] Add HDMI 2.0 support to DW HDMI QP TX

Cristian Ciocaltea cristian.ciocaltea at collabora.com
Wed Sep 2 11:00:53 PDT 2026


Hi Igor,

On 9/2/26 6:28 PM, Igor Paunovic wrote:
> Hi Cristian,
> 
>> This has been tested on the following boards:
> 
> One more, with a sink pair your boards cannot cover:
> 
> Tested-by: Igor Paunovic <royalnet026 at gmail.com> # RK3588 Orange Pi 5 Plus, dual HDMI
> 
> Setup: whole v11 on its stated base (drm-misc-next 47b823940e38),
> both SoC HDMI ports driven at once: a Samsung with HF-VSDB (max
> TMDS character rate 600 MHz, SCDC present) and a Sony limited to
> 300 MHz TMDS.
> 
> 1) HDMI 2.0 path: the Samsung now offers and runs 3840x2160 at 60 RGB
>    with a 594 MHz pixel clock (modetest-confirmed). Without the
>    series the same port tops out at 4K at 30. A stable picture at
>    594 MHz is only possible with scrambling and the 1/40 TMDS ratio
>    active; it stayed stable across boot, mode changes and hotplug.
> 
> 2) Non-2.0 fallback: the Sony keeps its 297 MHz 4K at 30 modes.
>    No regression.
> 
> 3) The result I care most about: this Sony in standby keeps EDID/5V
>    up but drops the link, and on my 7.2 stack that generates a
>    storm of detect/modeset cycles - measured 119-194 per hour,
>    enough to make the desktop stutter. On v11, twenty minutes of
>    standby produced ZERO events, and wake restored both sinks by
>    itself. Whatever share of that the cached-status detect and the
>    SCDC-loss handling each take - thank you.
> 
> 4) Hotplug on both ports: clean detach and reattach, no storms.
> 
> 5) Audio on a dead link: this morning my 7.2 stack took an SError
>    panic (regmap read in dw_hdmi_qp_bridge_clear_audio_infoframe
>    when a PCM was closed on a link whose SCDC never came up - full
>    UART trace available if useful). On v11 I could not reproduce
>    the class: six open/close cycles against the standby sink plus
>    one natural prepare-failure-then-close during replug all
>    survived cleanly. Caveat: different base kernels, so this is
>    not a clean A/B on the series alone.

Thanks for the detailed testing report!

> Scope: RGB output only (the YUV420 output series is separate), no
> USB-C DP on this base, VC4 side not exercised.

I will manually apply your T-b on the relevant patches before submitting a new
revision.

Cristian



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