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

[Andy Yan]

Hi Keith:

在 2023-12-13 09:40:31，"Keith Zhao" <keith.zhao at starfivetech.com> 写道：
>
>
>On 2023/12/11 20:13, Andy Yan wrote:
>> Hi Keith：
>> 
>> 在 2023-12-11 18:24:35，"Keith Zhao" <keith.zhao at 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 at 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 at 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 at 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.


I found A RK3128 based board XPI-3128 is for sale[0], which also has a inno-hdmi.
And Alx Bee is working on adding upstream support for it[1].

[0] https://www.geniatech.com/product/xpi-3128/

[1]https://patchwork.kernel.org/project/linux-arm-kernel/cover/20231213195125.212923-1-knaerzche@gmail.com/
>
>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