Re: [v3 5/6] drm/vs: Add hdmi driver

[Keith Zhao <keith.zhao@starfivetech.com>]

On 2023/12/11 20:13, Andy Yan wrote:
> Hi Keith：
> 
> 在 2023-12-11 18:24:35，"Keith Zhao" <keith.zhao@starfivetech.com> 写道：
>>hi Maxime:
>>hi Andy:
>>
>>On 2023/12/8 17:14, Maxime Ripard wrote:
>>> Hi,
>>> 
>>> On Fri, Dec 08, 2023 at 11:23:37AM +0800, Andy Yan wrote:
>>>> 在 2023-12-08 11:00:31，"Keith Zhao" <keith.zhao@starfivetech.com> 写道：
>>>> >
>>>> >
>>>> >On 2023/12/8 8:37, Andy Yan wrote:
>>>> >> Hi Keth：
>>>> >> 
>>>> >> 
>>>> >> 
>>>> >> 
>>>> >> 
>>>> >> 
>>>> >> 在 2023-12-07 18:48:13，"Keith Zhao" <keith.zhao@starfivetech.com> 写道：
>>>> >>>
>>>> >>>
>>>> >>>On 2023/12/7 17:02, Andy Yan wrote:
>>>> >>>> 
>>>> >>>> 
>>>> >>>> 
>>>> >>>> 
>>>> >>>> Hi Keith：
>>>> >>>> 
>>>> >>>> 
>>>> >>>> 
>>>> >>>> 
>>>> >>>> 
>>>> >>>> 
>>>> >>>> 
>>>> >>>> 
>>>> >>>> 
>>>> >>>> 
>>>> >>>> 
>>>> >>>> At 2023-12-06 22:11:33, "Keith Zhao" <keith.zhao@starfivetech.com> wrote:
>>>> >>>>>
>>>> >>>>>
>>>> >>>>>On 2023/12/6 20:56, Maxime Ripard wrote:
>>>> >>>>>> On Wed, Dec 06, 2023 at 08:02:55PM +0800, Keith Zhao wrote:
>>>> >>>>>>> >> +static const struct of_device_id starfive_hdmi_dt_ids[] = {
>>>> >>>>>>> >> +	{ .compatible = "starfive,jh7110-inno-hdmi",},
>>>> >>>>>>> > 
>>>> >>>>>>> > So it's inno hdmi, just like Rockchip then?
>>>> >>>>>>> > 
>>>> >>>>>>> > This should be a common driver.
>>>> >>>>>>>
>>>> >>>>>>> Rockchip has a inno hdmi IP. and Starfive has a inno hdmi IP.
>>>> >>>>>>> but the harewawre difference of them is big , it is not easy to use the common driver
>>>> >>>>>>> maybe i need the inno hdmi version here to make a distinction
>>>> >>>>>> 
>>>> >>>>>> I just had a look at the rockchip header file: all the registers but the
>>>> >>>>>> STARFIVE_* ones are identical.
>>>> >>>>>> 
>>>> >>>>>> There's no need to have two identical drivers then, please use the
>>>> >>>>>> rockchip driver instead.
>>>> >>>>>> 
>>>> >>>>>> Maxime
>>>> >>>>>
>>>> >>>>>ok, have a simple test , edid can get . i will continue 
>>>> >>>> 
>>>> >>>> Maybe you can take drivers/gpu/drm/bridge/synopsys/dw-hdmi as a reference， this
>>>> >>>> is also a hdmi ip used by rockchip/meson/sunxi/jz/imx。
>>>> >>>> We finally make it share one driver。
>>>> >>>>>
>>>> >>>hi Andy:
>>>> >>>
>>>> >>>dw_hdmi seems a good choice , it can handle inno hdmi hardware by define its dw_hdmi_plat_data.
>>>> >>>does it means i can write own driver files such as(dw_hdmi-starfive.c) based on dw_hdmi instead of add plat_data in inno_hdmi.c
>>>> >>>
>>>> >> 
>>>> >> I think the process maybe like this：
>>>> >> 
>>>> >> 1. split the inno_hdmi.c under rockchip to  inno_hdmi.c(the common part), inno_hdmi-rockchip.c(the soc specific part)
>>>> >> 2. move the common part inno_hdmi.c to drivers/gpu/drm/bridge/innosilicon/
>>>> >> 3. add startfive specific part, inno_hdmi-startfive.c
>>>> >> 
>>>> >> bellow git log from kernel three show how we convert  dw_hdmi to a common driver: 
>>>> >> 
>>>> >> 
>>>> >> 
>>>> >> 12b9f204e804 drm: bridge/dw_hdmi: add rockchip rk3288 support
>>>> >> 74af9e4d03b8 dt-bindings: Add documentation for rockchip dw hdmi
>>>> >> d346c14eeea9 drm: bridge/dw_hdmi: add function dw_hdmi_phy_enable_spare
>>>> >> a4d3b8b050d5 drm: bridge/dw_hdmi: clear i2cmphy_stat0 reg in hdmi_phy_wait_i2c_done
>>>> >> 632d035bace2 drm: bridge/dw_hdmi: add mode_valid support
>>>> >> 0cd9d1428322 drm: bridge/dw_hdmi: add support for multi-byte register width access
>>>> >> cd152393967e dt-bindings: add document for dw_hdmi
>>>> >> b21f4b658df8 drm: imx: imx-hdmi: move imx-hdmi to bridge/dw_hdmi
>>>> >> aaa757a092c2 drm: imx: imx-hdmi: split phy configuration to platform driver
>>>> >> 3d1b35a3d9f3 drm: imx: imx-hdmi: convert imx-hdmi to drm_bridge mode
>>>> >> c2c3848851a7 drm: imx: imx-hdmi: return defer if can't get ddc i2c adapter
>>>> >> b587833933de drm: imx: imx-hdmi: make checkpatch happy
>>>> >> 
>>>> >hi Andy:
>>>> >I got you means, 
>>>> >as I don't have a rockchip board on hand , to split the inno_hdmi.c can not be tested.
>>>> >
>>>> >how adout this idea:
>>>> >1、split the starfive_hdmi.c under verisilicion to  inno_hdmi.c(the common part), inno_hdmi-starfive.c(the soc specific part)
>>>> >2. move the common part inno_hdmi.c to drivers/gpu/drm/bridge/innosilicon/
>>>> >3. In the future, inno hdmi.c under rockchip will reuse the public driver.
>>>> 
>>>> I am not sure if drm maintainers are happy with this。
>>> 
>>> Not really, no.
>>> 
>>> Because we would still have two drivers for the same controller, and a
>>> common one that haven't really been tested on anything but a single
>>> platform. So arguably a worse situation than what you were suggesting in
>>> the first place.
>>> 
>>> The best solution would be to find someone with a Rockchip board to test
>>> your changes, or to get one if it's doable so you can test yourself.
>>
>>ok I will also try to buy a Rockchip 3036 board for self-test.
>>According to the commit log idea provided by Andy before, make the inno_hdmi driver common module.
> 
> I finally  make my rk3036 based kylin board bootup （use a linux 4.4 downstream bsp，I will find time to try boot
> it with mainline）。 So I can help do the test for rockchip side。
> 
> It seems not that easy to buy a rk3036 based board from market now。
en, The online store seems to have stopped selling rk3036 
really not easy to buy one , I write the code first , need help testing rk3036 in the future.

thanks
> 
>>
>>would the steps be ok? (if I tested rockchip and starifve pass)
>>1. split the inno_hdmi.c under rockchip to  inno_hdmi.c(the common part), inno_hdmi-rockchip.c(the soc specific part)
>>2. move the common part inno_hdmi.c to drivers/gpu/drm/bridge/innosilicon/
>>3. add startfive specific part, inno_hdmi-startfive.c
>>
>>Thanks
>>> 
>>> Maxime