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

From: Andy Yan
Date: Mon Jun 03 2024 - 14:51:20 EST


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