Re: [PATCH 01/11] dt-bindings: display: meson-dw-hdmi: Add compatible for S4 HDMI controller

[Ao Xu <ao.xu@amlogic.com>]

Hi Piotr，

     I will need about two more days to look into it. I will follow up with you ASAP.


在 2025/12/2 16:29, Piotr Oniszczuk 写道:
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> Ao,
> Any chance for updated s4 hdmi series for 6.18?
>
>
>> Wiadomość napisana przez Ao Xu <ao.xu@amlogic.com> w dniu 21 lis 2025, o godz. 03:55:
>>
>> Hi Piotr，
>>
>>      I will check this issue
>>
>> 在 2025/11/19 18:27, Piotr Oniszczuk 写道:
>>> [You don't often get email from piotr.oniszczuk@gmail.com. Learn why this is important at https://aka.ms/LearnAboutSenderIdentification ]
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>>> [ EXTERNAL EMAIL ]
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>>> Pls see inline
>>>
>>>> Wiadomość napisana przez Chuan Liu <chuan.liu@amlogic.com> w dniu 19 lis 2025, o godz. 03:57:
>>>>
>>>> Hi Piotr,
>>>>
>>>>
>>>> On 11/18/2025 10:50 PM, Piotr Oniszczuk wrote:
>>>>> [You don't often get email from piotr.oniszczuk@gmail.com. Learn why this is important at https://aka.ms/LearnAboutSenderIdentification ]
>>>>> [ EXTERNAL EMAIL ]
>>>>> Ao,
>>>>> Is there any chance to get this s4 drm hdmi series for current 6.18?
>>>>> (i tried backport this series to 6.18 but have some issues with reparent vpu_0_sel to sysclk_b_sel)
>>>> Why do we need to reparent vpu_0_sel to sysclk_b_sel? is there any
>>>> background here?
>>> Well - it looks it is because bug....
>>> Martin Blumenstingl had perfect eye and catch typo in patch https://lore.kernel.org/all/20250110-drm-s4-v1-11-cbc2d5edaae8@amlogic.com/:
>>>
>>> By replacing:
>>> assigned-clock-parents = <&clkc_periphs CLKID_FCLK_DIV3>,
>>> <0>, /* Do Nothing */
>>> <&clkc_periphs CLKID_VPU_0>,
>>> <&clkc_periphs CLKID_FCLK_DIV4>,
>>> <0>, /* Do Nothing */
>>> <&clkc_periphs CLKID_VAPB_0>;
>>>
>>> with:
>>> assigned-clock-parents = <&clkc_pll CLKID_FCLK_DIV3>,
>>> <0>, /* Do Nothing */
>>> <&clkc_periphs CLKID_VPU_0>,
>>> <&clkc_pll CLKID_FCLK_DIV4>,
>>> <0>, /* Do Nothing */
>>> <&clkc_periphs CLKID_VAPB_0>;
>>>
>>> dmesg is like this https://termbin.com/6020
>>>
>>> So i'm getting hdmi working - but only when device boots _without_ connected hdmi at boot (and connected later)
>>> If hdmi is connected at boot - boot hangs at:
>>>
>>>      0.341676] meson-dw-hdmi fe300000.hdmi-tx: Detected HDMI TX controller v2.01a with HDCP (meson_dw_hdmi_phy)
>>> [    0.342750] meson-dw-hdmi fe300000.hdmi-tx: registered DesignWare HDMI I2C bus driver
>>> [    0.343660] meson-drm ff000000.vpu: bound fe300000.hdmi-tx (ops meson_dw_hdmi_ops)
>>> [    0.344832] [drm] Initialized meson 1.0.0 for ff000000.vpu on minor 0
>>>
>>> FYI: It is after applying https://patchwork.kernel.org/project/linux-amlogic/cover/20250110-drm-s4-v1-0-cbc2d5edaae8@amlogic.com/ on mainline 6.18 (with some my adjustments on this series required by changes in 6.18).
>>> For VPU clk changes see https://github.com/warpme/minimyth2/blob/master/script/kernel/linux-6.18/files/0312-drm-meson-add-vpu-clk-setting-for-S4.patch
>>> It is 6.18 adaptation of https://patchwork.kernel.org/project/linux-amlogic/patch/20250110-drm-s4-v1-9-cbc2d5edaae8@amlogic.com/
>>>
>>> As kernel hangs - i have limited caps to drill where root cause is.
>>>
>>> Maybe above hang is reason of my backports or missing any pre-req required to get s4 drm working?
>>> Anyway - it will be good to test with updated to 6.18 series of Add DRM support for Amlogic S4 (plus info about any pre-req required to get s4 drm working)
>>>
>>>
>>>> The vpu_clk on S4 doesn't support sysclk_b_sel as one of its
>>>> selectable clock sources, so this reparent operation will definitely
>>>> fail. This has nothing to do with the kernel version.
>>>>
>>>>>> Wiadomość napisana przez Ao Xu via B4 Relay <devnull+ao.xu.amlogic.com@kernel.org> w dniu 10 sty 2025, o godz. 06:39:
>>>>>>
>>>>>> From: Ao Xu <ao.xu@amlogic.com>
>>>>>>
>>>>>> Add devicetree document for S4 HDMI controller
>>>>>>
>>>>>> Signed-off-by: Ao Xu <ao.xu@amlogic.com>
>>>>>> ---
>>>>>> Documentation/devicetree/bindings/display/amlogic,meson-dw-hdmi.yaml | 1 +
>>>>>> 1 file changed, 1 insertion(+)
>>>>>>
>>>>>> diff --git a/Documentation/devicetree/bindings/display/amlogic,meson-dw-hdmi.yaml b/Documentation/devicetree/bindings/display/amlogic,meson-dw-hdmi.yaml
>>>>>> index 84d68b8cfccc86fd87a6a0fd2b70af12e51eb8a4..6e0a8369eee915fab55af24d450a6c40e08def38 100644
>>>>>> --- a/Documentation/devicetree/bindings/display/amlogic,meson-dw-hdmi.yaml
>>>>>> +++ b/Documentation/devicetree/bindings/display/amlogic,meson-dw-hdmi.yaml
>>>>>> @@ -55,6 +55,7 @@ properties:
>>>>>>            - const: amlogic,meson-gx-dw-hdmi
>>>>>>        - enum:
>>>>>>            - amlogic,meson-g12a-dw-hdmi # G12A (S905X2, S905Y2, S905D2)
>>>>>> +          - amlogic,meson-s4-dw-hdmi # S4 (S905Y4)
>>>>>>
>>>>>>    reg:
>>>>>>      maxItems: 1
>>>>>>
>>>>>> --
>>>>>> 2.43.0
>>>>>>
>>>>>>
>>>>>>
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