Re: [PATCH 00/14] Add initial support for the Rockchip RK3588 HDMI TX Controller

[Andy Yan]

Hi Neil:

On 6/3/24 16:55, Neil Armstrong wrote:
> Hi Christian,
>
> On 01/06/2024 15:12, Cristian Ciocaltea wrote:
> > The RK3588 SoC family integrates a Quad-Pixel (QP) variant of the
> > Synopsys DesignWare HDMI TX controller used in the previous SoCs.
> >
> > It is HDMI 2.1 compliant and supports the following features, among
> > others:
> .
>
> ..
>
> > * SCDC I2C DDC access
> > * TMDS Scrambler enabling 2160p@60Hz with RGB/YCbCr4:4:4
> > * YCbCr4:2:0 enabling 2160p@60Hz at lower HDMI link speeds
> > * Multi-stream audio
> > * Enhanced Audio Return Channel (EARC)
> -> Those features were already supported by the HDMI 2.0a compliant HW, just
> list the _new_ features for HDMI 2.1
>
> I did a quick review of your patchset and I don't understand why you need
> to add a separate dw-hdmi-qp.c since you only need simple variants of the I2C
> bus, infoframe and bridge setup.
>
> Can you elaborate further ? isn't this Quad-Pixel (QP) TX controller version
> detectable at runtime ?
>
> I would prefer to keep a single dw-hdmi driver if possible.



The QP HDMI controller is a completely different variant with totally different
registers layout, see PATCH 13/14.
I think make it a separate driver will be easier for development and maintenance.
> Thanks,
> Neil
>
> > This is the last required component that needs to be supported in order
> > to enable the HDMI output functionality on the RK3588 based SBCs, such
> > as the RADXA Rock 5B. The other components are the Video Output
> > Processor (VOP2) and the Samsung IP based HDMI/eDP TX Combo PHY, for
> > which basic support has been already made available via [1] and [2],
> > respectively.
> >
> > The patches are grouped as follows:
> > * PATCH 1..7: DW HDMI TX driver refactor to minimize code duplication in
> >    the new QP driver (no functional changes intended)
> >
> > * PATCH 8..11: Rockchip DW HDMI glue driver cleanup/improvements (no
> >    functional changes intended)
> >
> > * PATCH 12..13: The new DW HDMI QP TX driver reusing the previously
> >    exported functions and structs from existing DW HDMI TX driver
> >
> > * PATCH 14: Rockchip DW HDMI glue driver update to support RK3588 and
> >    make use of DW HDMI QP TX
> >
> > They provide just the basic HDMI support for now, i.e. RGB output up to
> > 4K@60Hz, without audio, CEC or any of the HDMI 2.1 specific features.
> > Also note the vop2 driver is currently not able to properly handle all
> > display modes supported by the connected screens, e.g. it doesn't cope
> > with non-integer refresh rates.
> >
> > A possible workaround consists of enabling the display controller to
> > make use of the clock provided by the HDMI PHY PLL. This is still work
> > in progress and will be submitted later, as well as the required DTS
> > updates.
> >
> > To facilitate testing and experimentation, all HDMI output related
> > patches, including those part of this series, are available at [3].
> > So far I could only verify this on the RADXA Rock 3A and 5B boards.
> >
> > Thanks,
> > Cristian
> >
> > [1]: 5a028e8f062f ("drm/rockchip: vop2: Add support for rk3588")
> > [2]: 553be2830c5f ("phy: rockchip: Add Samsung HDMI/eDP Combo PHY driver")
> > [3]: https://gitlab.collabora.com/hardware-enablement/rockchip-3588/linux/-/commits/rk3588-hdmi-bridge-v6.10-rc1
> >
> > Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@xxxxxxxxxxxxx>
> > ---
> > Cristian Ciocaltea (14):
> >        drm/bridge: dw-hdmi: Simplify clock handling
> >        drm/bridge: dw-hdmi: Add dw-hdmi-common.h header
> >        drm/bridge: dw-hdmi: Commonize dw_hdmi_i2c_adapter()
> >        drm/bridge: dw-hdmi: Factor out AVI infoframe setup
> >        drm/bridge: dw-hdmi: Factor out vmode setup
> >        drm/bridge: dw-hdmi: Factor out hdmi_data_info setup
> >        drm/bridge: dw-hdmi: Commonize dw_hdmi_connector_create()
> >        drm/rockchip: dw_hdmi: Use modern drm_device based logging
> >        drm/rockchip: dw_hdmi: Simplify clock handling
> >        drm/rockchip: dw_hdmi: Use devm_regulator_get_enable()
> >        drm/rockchip: dw_hdmi: Drop superfluous assignments of mpll_cfg, cur_ctr and phy_config
> >        dt-bindings: display: rockchip,dw-hdmi: Add compatible for RK3588
> >        drm/bridge: synopsys: Add DW HDMI QP TX controller driver
> >        drm/rockchip: dw_hdmi: Add basic RK3588 support
> >
> >   .../display/rockchip/rockchip,dw-hdmi.yaml         | 127 +++-
> >   drivers/gpu/drm/bridge/synopsys/Makefile           |   2 +-
> >   drivers/gpu/drm/bridge/synopsys/dw-hdmi-common.h   | 179 +++++
> >   drivers/gpu/drm/bridge/synopsys/dw-hdmi-qp.c       | 787 +++++++++++++++++++
> >   drivers/gpu/drm/bridge/synopsys/dw-hdmi-qp.h       | 831 +++++++++++++++++++++
> >   drivers/gpu/drm/bridge/synopsys/dw-hdmi.c          | 353 +++------
> >   drivers/gpu/drm/rockchip/dw_hdmi-rockchip.c        | 351 +++++++--
> >   include/drm/bridge/dw_hdmi.h                       |   8 +
> >   8 files changed, 2290 insertions(+), 348 deletions(-)
> > ---
> > base-commit: 1613e604df0cd359cf2a7fbd9be7a0bcfacfabd0
> > change-id: 20240601-b4-rk3588-bridge-upstream-a27baff1b8fc