linux-kernel - Re: [PATCH 2/3] arm64: dts: allwinner: a64: explicitly assign clock parent for TCON0

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <bab2e7c53385da06a44b449077c7241a@manjaro.org>
Date: Sun, 15 Dec 2024 09:00:23 +0100
From: Dragan Simic <dsimic@...jaro.org>
To: Vasily Khoruzhick <anarsoul@...il.com>
Cc: Rob Herring <robh@...nel.org>, Krzysztof Kozlowski <krzk+dt@...nel.org>,
 Conor Dooley <conor+dt@...nel.org>, Chen-Yu Tsai <wens@...e.org>, Jernej
 Skrabec <jernej.skrabec@...il.com>, Samuel Holland <samuel@...lland.org>,
 Michael Turquette <mturquette@...libre.com>, Stephen Boyd
 <sboyd@...nel.org>, Maxime Ripard <mripard@...nel.org>, Roman Beranek
 <me@...y.cz>, devicetree@...r.kernel.org,
 linux-arm-kernel@...ts.infradead.org, linux-sunxi@...ts.linux.dev,
 linux-kernel@...r.kernel.org, linux-clk@...r.kernel.org
Subject: Re: [PATCH 2/3] arm64: dts: allwinner: a64: explicitly assign clock
 parent for TCON0

Hello Vasily,

On 2024-12-15 06:34, Vasily Khoruzhick wrote:
> TCON0 seems to need a different clock parent depending on output type.
> For RGB it has to be PLL-VIDEO0-2X, while for DSI it has to be PLL-MIPI
> 
> Video output doesn't work if incorrect clock is assigned.
> 
> On my Pinebook I manually configured PLL-VIDEO0-2X and PLL-MIPI to the 
> same
> rate, and while video output works fine with PLL-VIDEO0-2X, it doesn't
> work at all (as in no picture) with PLL-MIPI.
> 
> Fixes: ca1170b69968 ("clk: sunxi-ng: a64: force select PLL_MIPI in 
> TCON0 mux")
> Signed-off-by: Vasily Khoruzhick <anarsoul@...il.com>

Thanks for fixing this issue!  I've been banging my head for a while
about how to fix it without introducing new DT properties, and I hope
that the maintainers will like your approach.

I'd suggest that the patch description is improved further a bit, by
incorporating some parts of the good description of the issue that's
already in the cover letter.  With that addressed, please feel free
to include

Reviewed-by: Dragan Simic <dsimic@...jaro.org>

> ---
>  arch/arm64/boot/dts/allwinner/sun50i-a64-pinebook.dts | 2 ++
>  arch/arm64/boot/dts/allwinner/sun50i-a64-teres-i.dts  | 2 ++
>  arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi         | 2 ++
>  3 files changed, 6 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/allwinner/sun50i-a64-pinebook.dts
> b/arch/arm64/boot/dts/allwinner/sun50i-a64-pinebook.dts
> index 379c2c8466f5..86d44349e095 100644
> --- a/arch/arm64/boot/dts/allwinner/sun50i-a64-pinebook.dts
> +++ b/arch/arm64/boot/dts/allwinner/sun50i-a64-pinebook.dts
> @@ -390,6 +390,8 @@ &sound {
>  &tcon0 {
>  	pinctrl-names = "default";
>  	pinctrl-0 = <&lcd_rgb666_pins>;
> +	assigned-clocks = <&ccu CLK_TCON0>;
> +	assigned-clock-parents = <&ccu CLK_PLL_VIDEO0_2X>;
> 
>  	status = "okay";
>  };
> diff --git a/arch/arm64/boot/dts/allwinner/sun50i-a64-teres-i.dts
> b/arch/arm64/boot/dts/allwinner/sun50i-a64-teres-i.dts
> index b407e1dd08a7..ec055510af8b 100644
> --- a/arch/arm64/boot/dts/allwinner/sun50i-a64-teres-i.dts
> +++ b/arch/arm64/boot/dts/allwinner/sun50i-a64-teres-i.dts
> @@ -369,6 +369,8 @@ &sound {
>  &tcon0 {
>  	pinctrl-names = "default";
>  	pinctrl-0 = <&lcd_rgb666_pins>;
> +	assigned-clocks = <&ccu CLK_TCON0>;
> +	assigned-clock-parents = <&ccu CLK_PLL_VIDEO0_2X>;
> 
>  	status = "okay";
>  };
> diff --git a/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi
> b/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi
> index a5c3920e0f04..0fecf0abb204 100644
> --- a/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi
> +++ b/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi
> @@ -445,6 +445,8 @@ tcon0: lcd-controller@...c000 {
>  			clock-names = "ahb", "tcon-ch0";
>  			clock-output-names = "tcon-data-clock";
>  			#clock-cells = <0>;
> +			assigned-clocks = <&ccu CLK_TCON0>;
> +			assigned-clock-parents = <&ccu CLK_PLL_MIPI>;
>  			resets = <&ccu RST_BUS_TCON0>, <&ccu RST_BUS_LVDS>;
>  			reset-names = "lcd", "lvds";