From: Raphael Gallais-Pou Date: Tue, 10 Feb 2026 10:03:56 +0000 (+0100) Subject: arm64: dts: st: add ltdc support on stm32mp235 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=5ef22cf564d571402d17883aa313d94842447acf;p=thirdparty%2Fkernel%2Fstable.git arm64: dts: st: add ltdc support on stm32mp235 Add the LTDC node for stm32mp235 SoC and handle its loopback clocks. ck_ker_ltdc has the CLK_SET_RATE_PARENT flag. While having this flag is semantically correct, it for now leads to an improper setting of the clock rate. The ck_ker_ltdc parent clock is the flexgen 27, which does not support changing rates yet. To overcome this issue, a fixed clock can be used for the kernel clock. Signed-off-by: Raphael Gallais-Pou Link: https://lore.kernel.org/r/20260210-display-v2-3-0592bd514958@foss.st.com Signed-off-by: Alexandre Torgue --- diff --git a/arch/arm64/boot/dts/st/stm32mp231.dtsi b/arch/arm64/boot/dts/st/stm32mp231.dtsi index 03c71a403f13..8afd175b9e1c 100644 --- a/arch/arm64/boot/dts/st/stm32mp231.dtsi +++ b/arch/arm64/boot/dts/st/stm32mp231.dtsi @@ -45,6 +45,12 @@ clock-frequency = <0>; }; + clk_flexgen_27_fixed: clk-54000000 { + #clock-cells = <0>; + compatible = "fixed-clock"; + clock-frequency = <54000000>; + }; + clk_rcbsec: clk-64000000 { compatible = "fixed-clock"; #clock-cells = <0>; diff --git a/arch/arm64/boot/dts/st/stm32mp235.dtsi b/arch/arm64/boot/dts/st/stm32mp235.dtsi index 2719c088dd59..ae98f503529f 100644 --- a/arch/arm64/boot/dts/st/stm32mp235.dtsi +++ b/arch/arm64/boot/dts/st/stm32mp235.dtsi @@ -5,6 +5,12 @@ */ #include "stm32mp233.dtsi" +<dc { + compatible = "st,stm32mp255-ltdc"; + clocks = <&clk_flexgen_27_fixed>, <&rcc CK_BUS_LTDC>, <&syscfg>, <&lvds>; + clock-names = "lcd", "bus", "ref", "lvds"; +}; + &rifsc { vdec: vdec@480d0000 { compatible = "st,stm32mp25-vdec";