[PATCH v3 1/4] ARM: dts: stm32: add LTDC support for STM32MP13x SoC family

From: Raphael Gallais-Pou
Date: Fri Feb 23 2024 - 07:39:21 EST


STM32MP13x SoC family embeds a new version of LTDC (Liquid crystal
display - Thin film transistor) Display Controller.

It provides a parallel digital RGB (red, green, blue) and signals for
horizontal, vertical synchronization, pixel clock and data enable as
output to interface directly to a variety of LCD-TFT panels.

Main features
* 2 input layers blended together to compose the display
* Cropping of layers from any input size and location
* Multiple input pixel formats:
– Predefined ARGB, with 7 formats: ARGB8888, ABGR8888, RGBA8888,
BGRA8888, RGB565, BGR565, RGB888packed.
– Flexible ARGB, allowing any width and location for A,R,G,B
components.
– Predefined YUV, with 3 formats: YUV422-1L (FourCC: YUYV,
Interleaved), YUV420-2L (FourCC: NV12, semi planar), YUV420-3L
(FourCC: Yxx, full planar) with some flexibility on the sequence of
the component.
* Color look-up table (CLUT) up to 256 colors (256x24 bits) per layer
* Color transparency keying
* Composition with flexible window position and size versus output
display
* Blending with flexible layer order and alpha value (per pixel or
constant)
* Background underlying color
* Gamma with non-linear configurable table
* Dithering for output with less bits per component (pseudo-random on
2 bits)
* Polarity inversion for HSync, VSync, and DataEnable outputs
* Output as RGB888 24 bpp or YUV422 16 bpp
* Secure layer (using Layer2) capability, with grouped regs and
additional interrupt set
* Interrupts based on 7 different events
* AXI master interface with long efficient bursts (64 or 128 bytes)

Signed-off-by: Raphael Gallais-Pou <raphael.gallais-pou@xxxxxxxxxxx>
Signed-off-by: Yannick Fertre <yannick.fertre@xxxxxxxxxxx>
---
arch/arm/boot/dts/st/stm32mp135.dtsi | 11 +++++++++++
1 file changed, 11 insertions(+)

diff --git a/arch/arm/boot/dts/st/stm32mp135.dtsi b/arch/arm/boot/dts/st/stm32mp135.dtsi
index 68d32f9f5314..834a4d545fe4 100644
--- a/arch/arm/boot/dts/st/stm32mp135.dtsi
+++ b/arch/arm/boot/dts/st/stm32mp135.dtsi
@@ -19,5 +19,16 @@ dcmipp: dcmipp@5a000000 {
port {
};
};
+
+ ltdc: display-controller@5a001000 {
+ compatible = "st,stm32-ltdc";
+ reg = <0x5a001000 0x400>;
+ interrupts = <GIC_SPI 88 IRQ_TYPE_LEVEL_HIGH>,
+ <GIC_SPI 89 IRQ_TYPE_LEVEL_HIGH>;
+ clocks = <&rcc LTDC_PX>;
+ clock-names = "lcd";
+ resets = <&scmi_reset RST_SCMI_LTDC>;
+ status = "disabled";
+ };
};
};

--
2.25.1