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Add Amlogic A311D2 and Khadas Vim4 Board Support

PATCH Superseded Lucas Tanure 5 participants 10 messages Jun 20, 2023 – Jun 21, 2023

Subsystems (2)

v2 of 7 Superseded Latest is v7 →

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v2 cover Add Amlogic A311D2 and Khadas Vim4 Board Support

The Khadas VIM4 uses the Amlogic A311D2 SoC, based on the Amlogic Meson T7 family. This chip is not the same as A311D used in Vim3 board.

Work based on Khadas 5.4 branch:
https://github.com/khadas/linux/tree/khadas-vims-5.4.y

The current status is Vim4 board booting to emergency shell via uart.

Board Features:
- 8GB LPDDR4X 2016MHz
- 32GB eMMC 5.1 storage
- 32MB SPI flash
- 10/100/1000 Base-T Ethernet
- AP6275S Wireless (802.11 a/b/g/n/ac/ax, BT5.1)
- HDMI 2.1 video
- HDMI Input
- 1x USB 2.0 + 1x USB 3.0 ports
- 1x USB-C (power) with USB 2.0 OTG
- 3x LED's (1x red, 1x blue, 1x white)
- 3x buttons (power, function, reset)
- M2 socket with PCIe, USB, ADC & I2C
- 40pin GPIO Header
- 1x micro SD card slot

Changes Since v1:
- Drop the T7 clock driver as it is not needed for serial boot. It will later use the S4 clock
driver as S4 and T7 seems to be similar chips.
- Use "arm,gic-400" for interrupt controller to fix dtb_check
- Remove CPU node properties not needed for serial boot
- Move UART node to apb4 node
- Drop T7 UART compatible line and use S4 uart
- Use psci V1 instead of 0.2, it works, but I can't verify is correct as the datasheet I have
doesn't contain that information.
- Remove compatible from meson-t7.dtsi, move it to vim4 board dts
- Add memory node with 8GB. Not sure about this one, works without, but doesn't detect 8GB
- Use defines for GIC_CPU_MASK_SIMPLE, IRQ_TYPE_LEVEL_LOW, IRQ_TYPE_LEVEL_HIGH instead of hardcoded values

Lucas Tanure (2):
dt-bindings: arm: amlogic: add Amlogic A311D2 bindings
arm64: dts: meson-t7-a311d2-khadas-vim4: add initial device-tree

 .../devicetree/bindings/arm/amlogic.yaml      |   7 +
 arch/arm64/boot/dts/amlogic/Makefile          |   1 +
 .../amlogic/meson-t7-a311d2-khadas-vim4.dts   |  52 ++++++
 arch/arm64/boot/dts/amlogic/meson-t7.dtsi     | 158 ++++++++++++++++++
 4 files changed, 218 insertions(+)
 create mode 100644 arch/arm64/boot/dts/amlogic/meson-t7-a311d2-khadas-vim4.dts
 create mode 100644 arch/arm64/boot/dts/amlogic/meson-t7.dtsi

--
2.41.0

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#1 lore raw

PATCH v2 1/2 dt-bindings: arm: amlogic: add Amlogic A311D2 bindings

Add bindings for the Khadas Vim4 board, using A311D2 soc, a Meson T7 family chip.

---
 Documentation/devicetree/bindings/arm/amlogic.yaml | 7 +++++++
 1 file changed, 7 insertions(+)
Documentation/devicetree/bindings/arm/amlogic.yaml +7 -0
index 274ee0890312..8dbd65170c50 100644
@@ -211,6 +211,13 @@ properties:
               - amlogic,aq222
           - const: amlogic,s4
 
+      - description: Boards with the Amlogic Meson t7 A311D2 SoC
+        items:
+          - enum:
+              - khadas,vim4
+          - const: amlogic,a311d2
+          - const: amlogic,t7
+
 additionalProperties: true
 
 ...
Signature · 7 lines
2.41.0


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#2 lore raw

PATCH v2 2/2 arm64: dts: meson-t7-a311d2-khadas-vim4: add initial device-tree

In reply to Lucas Tanure

The Khadas VIM4 uses the Amlogic A311D2 SoC, based on the Amlogic T7 SoC family, on a board with the same form factor as the VIM3 models.

- 8GB LPDDR4X 2016MHz
- 32GB eMMC 5.1 storage
- 32MB SPI flash
- 10/100/1000 Base-T Ethernet
- AP6275S Wireless (802.11 a/b/g/n/ac/ax, BT5.1)
- HDMI 2.1 video
- HDMI Input
- 1x USB 2.0 + 1x USB 3.0 ports
- 1x USB-C (power) with USB 2.0 OTG
- 3x LED's (1x red, 1x blue, 1x white)
- 3x buttons (power, function, reset)
- M2 socket with PCIe, USB, ADC & I2C
- 40pin GPIO Header
- 1x micro SD card slot

---
 arch/arm64/boot/dts/amlogic/Makefile          |   1 +
 .../amlogic/meson-t7-a311d2-khadas-vim4.dts   |  52 ++++++
 arch/arm64/boot/dts/amlogic/meson-t7.dtsi     | 158 ++++++++++++++++++
 3 files changed, 211 insertions(+)
 create mode 100644 arch/arm64/boot/dts/amlogic/meson-t7-a311d2-khadas-vim4.dts
 create mode 100644 arch/arm64/boot/dts/amlogic/meson-t7.dtsi
arch/arm64/boot/dts/amlogic/Makefile +1 -0
index cd1c5b04890a..1c5846bd1ca0 100644
@@ -74,3 +74,4 @@ dtb-$(CONFIG_ARCH_MESON) += meson-sm1-odroid-hc4.dtb
 dtb-$(CONFIG_ARCH_MESON) += meson-sm1-sei610.dtb
 dtb-$(CONFIG_ARCH_MESON) += meson-sm1-x96-air-gbit.dtb
 dtb-$(CONFIG_ARCH_MESON) += meson-sm1-x96-air.dtb
+dtb-$(CONFIG_ARCH_MESON) += meson-t7-a311d2-khadas-vim4.dtb
arch/arm64/boot/dts/amlogic/meson-t7-a311d2-khadas-vim4.dts new file +52 -0

52 lines not on this page · raw message

arch/arm64/boot/dts/amlogic/meson-t7.dtsi new file +158 -0

158 lines not on this page · raw message

--
2.41.0

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#3 lore raw

Re: [PATCH v2 2/2] arm64: dts: meson-t7-a311d2-khadas-vim4: add initial device-tree

Hi Lucas:

Quoted 237 lines · Lucas Tanure

The Khadas VIM4 uses the Amlogic A311D2 SoC, based on the Amlogic T7 SoC family, on a board with the same form factor as the VIM3 models.

- 8GB LPDDR4X 2016MHz
- 32GB eMMC 5.1 storage
- 32MB SPI flash
- 10/100/1000 Base-T Ethernet
- AP6275S Wireless (802.11 a/b/g/n/ac/ax, BT5.1)
- HDMI 2.1 video
- HDMI Input
- 1x USB 2.0 + 1x USB 3.0 ports
- 1x USB-C (power) with USB 2.0 OTG
- 3x LED's (1x red, 1x blue, 1x white)
- 3x buttons (power, function, reset)
- M2 socket with PCIe, USB, ADC & I2C
- 40pin GPIO Header
- 1x micro SD card slot

---
 arch/arm64/boot/dts/amlogic/Makefile          |   1 +
 .../amlogic/meson-t7-a311d2-khadas-vim4.dts   |  52 ++++++
 arch/arm64/boot/dts/amlogic/meson-t7.dtsi     | 158 ++++++++++++++++++
 3 files changed, 211 insertions(+)
 create mode 100644 arch/arm64/boot/dts/amlogic/meson-t7-a311d2-khadas-vim4.dts
 create mode 100644 arch/arm64/boot/dts/amlogic/meson-t7.dtsi
arch/arm64/boot/dts/amlogic/Makefile +1 -0
index cd1c5b04890a..1c5846bd1ca0 100644
@@ -74,3 +74,4 @@ dtb-$(CONFIG_ARCH_MESON) += meson-sm1-odroid-hc4.dtb
 dtb-$(CONFIG_ARCH_MESON) += meson-sm1-sei610.dtb
 dtb-$(CONFIG_ARCH_MESON) += meson-sm1-x96-air-gbit.dtb
 dtb-$(CONFIG_ARCH_MESON) += meson-sm1-x96-air.dtb
+dtb-$(CONFIG_ARCH_MESON) += meson-t7-a311d2-khadas-vim4.dtb
arch/arm64/boot/dts/amlogic/meson-t7-a311d2-khadas-vim4.dts new file +52 -0
new file mode 100644
index 000000000000..04cc8b0dfd8c
@@ -0,0 +1,52 @@
+// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+/*
+ * Copyright (c) 2022 Wesion, Inc. All rights reserved.
+ */
+
+/dts-v1/;
+
+#include "meson-t7.dtsi"
+
+/ {
+	model = "Khadas vim4";
+	compatible = "khadas,vim4", "amlogic,a311d2", "amlogic,t7";
+
+	aliases {
+		serial0 = &uart_A;
+	};
+
+	memory@0 {
+		device_type = "memory";
+		reg = <0x0 0x0 0x2 0x0>; /* 8 GB */
+	};
+
+	reserved-memory {
+		#address-cells = <2>;
+		#size-cells = <2>;
+		ranges;
+
+		/* 3 MiB reserved for ARM Trusted Firmware (BL31) */
+		secmon_reserved: secmon@5000000 {
+			reg = <0x0 0x05000000 0x0 0x300000>;
+			no-map;
+		};
+
+		/* 32 MiB reserved for ARM Trusted Firmware (BL32) */
+		secmon_reserved_bl32: secmon@5300000 {
+			reg = <0x0 0x05300000 0x0 0x2000000>;
+			no-map;
+		};
+	};
+
+	xtal: xtal-clk {
+		compatible = "fixed-clock";
+		clock-frequency = <24000000>;
+		clock-output-names = "xtal";
+		#clock-cells = <0>;
+	};
+
+};
+
+&uart_A {
+	status = "okay";
+};
arch/arm64/boot/dts/amlogic/meson-t7.dtsi new file +137 -0
new file mode 100644
index 000000000000..b268889bf8ea
@@ -0,0 +1,158 @@
+// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+/*
+ * Copyright (c) 2019 Amlogic, Inc. All rights reserved.
+ */
+
+#include <dt-bindings/interrupt-controller/arm-gic.h>
+
+/ {
+	interrupt-parent = <&gic>;
+	#address-cells = <2>;
+	#size-cells = <2>;
+
+	cpus {
+		#address-cells = <0x2>;
+		#size-cells = <0x0>;
+
+		cpu-map {
+			cluster0 {
+				core0 {
+					cpu = <&cpu100>;
+				};
+				core1 {
+					cpu = <&cpu101>;
+				};
+				core2 {
+					cpu = <&cpu102>;
+				};
+				core3 {
+					cpu = <&cpu103>;
+				};
+			};
+
+			cluster1 {
+				core0 {
+					cpu = <&cpu0>;
+				};
+				core1 {
+					cpu = <&cpu1>;
+				};
+				core2 {
+					cpu = <&cpu2>;
+				};
+				core3 {
+					cpu = <&cpu3>;
+				};
+			};
+		};
+
+		cpu100: cpu@100 {
+			device_type = "cpu";
+			compatible = "arm,cortex-a53";
+			reg = <0x0 0x100>;
+			enable-method = "psci";
+		};
+
+		cpu101: cpu@101{
+			device_type = "cpu";
+			compatible = "arm,cortex-a53";
+			reg = <0x0 0x101>;
+			enable-method = "psci";
+		};
+
+		cpu102: cpu@102 {
+			device_type = "cpu";
+			compatible = "arm,cortex-a53";
+			reg = <0x0 0x102>;
+			enable-method = "psci";
+		};
+
+		cpu103: cpu@103 {
+			device_type = "cpu";
+			compatible = "arm,cortex-a53";
+			reg = <0x0 0x103>;
+			enable-method = "psci";
+		};
+
+		cpu0: cpu@0 {
+			device_type = "cpu";
+			compatible = "arm,cortex-a73";
+			reg = <0x0 0x0>;
+			enable-method = "psci";
+		};
+
+		cpu1: cpu@1 {
+			device_type = "cpu";
+			compatible = "arm,cortex-a73";
+			reg = <0x0 0x1>;
+			enable-method = "psci";
+		};
+
+		cpu2: cpu@2 {
+			device_type = "cpu";
+			compatible = "arm,cortex-a73";
+			reg = <0x0 0x2>;
+			enable-method = "psci";
+		};
+
+		cpu3: cpu@3 {
+			device_type = "cpu";
+			compatible = "arm,cortex-a73";
+			reg = <0x0 0x3>;
+			enable-method = "psci";
+		};
+	};
+
+	timer {
+		compatible = "arm,armv8-timer";
+		interrupts = <GIC_PPI 13 (GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_LOW)>,
+			     <GIC_PPI 14 (GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_LOW)>,
+			     <GIC_PPI 11 (GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_LOW)>,
+			     <GIC_PPI 10 (GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_LOW)>;
+	};
+
+	psci {
+		compatible = "arm,psci-1.0";
+		method = "smc";
+	};
+
+	sm: secure-monitor {
+		compatible = "amlogic,meson-gxbb-sm";
+	};
+
+	soc {
+		compatible = "simple-bus";
+		#address-cells = <2>;
+		#size-cells = <2>;
+		ranges;
+
+		gic: interrupt-controller@fff01000 {
+			compatible = "arm,gic-400";
+			#interrupt-cells = <3>;
+			#address-cells = <0>;
+			interrupt-controller;
+			reg = <0x0 0xfff01000 0 0x1000>,
+			      <0x0 0xfff02000 0 0x0100>;
+			interrupts = <GIC_PPI 9 (GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_HIGH)>;
+		};

arch/arm64/boot/dts/amlogic/meson-t7.dtsi line 147

Quoted 10 lines
arch/arm64/boot/dts/amlogic/meson-t7.dtsi new file +10 -0
+
+		apb4: bus@fe000000 {
+			compatible = "simple-bus";
+			reg = <0x0 0xfe000000 0x0 0x480000>;
+			#address-cells = <2>;
+			#size-cells = <2>;
+			ranges = <0x0 0x0 0x0 0xfe000000 0x0 0x480000>;
+
+			uart_A: serial@78000 {
+				compatible = "amlogic,meson-t7-uart",
                                              ~~~~~~~~~~~~~~~~~

if you introduce new compatible string, then at least you need to document it so Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml need to be updated

but my qeustion here, why bother introducing new compatible string if nothing changed with the compatible data? given the uart is same IP with g12a, can't we just use "amlogic,meson-g12-uart" for this? no only it will reduce the structure length of meson_uart_dt_match[], but also relieve maintainer's review burden?

Quoted 20 lines
arch/arm64/boot/dts/amlogic/meson-t7.dtsi new file +11 -1
+					     "amlogic,meson-s4-uart";
 
+				reg = <0x0 0x78000 0x0 0x18>;
+				interrupts = <GIC_SPI 168 IRQ_TYPE_EDGE_RISING>;
+				status = "disabled";
+				clocks = <&xtal>, <&xtal>, <&xtal>;
+				clock-names = "xtal", "pclk", "baud";
+			};
+		};
+
+	};
+};
--

2.41.0

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Signature · 3 lines
Yixun Lan (dlan)
Gentoo Linux Developer
GPG Key ID AABEFD55
#4 lore raw

Re: [PATCH v2 2/2] arm64: dts: meson-t7-a311d2-khadas-vim4: add initial device-tree

Quoted 10 lines · Yixun Lan

arch/arm64/boot/dts/amlogic/meson-t7.dtsi line 147

Quoted 9 lines
arch/arm64/boot/dts/amlogic/meson-t7.dtsi new file +9 -0
+		apb4: bus@fe000000 {
+			compatible = "simple-bus";
+			reg = <0x0 0xfe000000 0x0 0x480000>;
+			#address-cells = <2>;
+			#size-cells = <2>;
+			ranges = <0x0 0x0 0x0 0xfe000000 0x0 0x480000>;
+
+			uart_A: serial@78000 {
+				compatible = "amlogic,meson-t7-uart",
                                              ~~~~~~~~~~~~~~~~~
Quoted 7 lines

if you introduce new compatible string, then at least you need to document it so Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml need to be updated

but my qeustion here, why bother introducing new compatible string if nothing changed with the compatible data? given the uart is same IP with g12a, can't we just use "amlogic,meson-g12-uart" for this? no only it will reduce the structure length of meson_uart_dt_match[], but also relieve maintainer's review burden?

https://elixir.bootlin.com/linux/v6.1-rc1/source/Documentation/devicetree/bindings/writing-bindings.rst#L42

Best regards,
Krzysztof

#5 lore raw

Re: [PATCH v2 2/2] arm64: dts: meson-t7-a311d2-khadas-vim4: add initial device-tree

Quoted 20 lines · Krzysztof Kozlowski
Quoted 9 lines · Yixun Lan

arch/arm64/boot/dts/amlogic/meson-t7.dtsi line 147

Quoted 9 lines
arch/arm64/boot/dts/amlogic/meson-t7.dtsi new file +9 -0
+            apb4: bus@fe000000 {
+                    compatible = "simple-bus";
+                    reg = <0x0 0xfe000000 0x0 0x480000>;
+                    #address-cells = <2>;
+                    #size-cells = <2>;
+                    ranges = <0x0 0x0 0x0 0xfe000000 0x0 0x480000>;
+
+                    uart_A: serial@78000 {
+                            compatible = "amlogic,meson-t7-uart",
Quoted 8 lines
                                              ~~~~~~~~~~~~~~~~~

if you introduce new compatible string, then at least you need to document it so Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml need to be updated

but my qeustion here, why bother introducing new compatible string if nothing changed with the compatible data? given the uart is same IP with g12a, can't we just use "amlogic,meson-g12-uart" for this? no only it will reduce the structure length of meson_uart_dt_match[], but also relieve maintainer's review burden?

Quoted 5 lines

https://elixir.bootlin.com/linux/v6.1-rc1/source/Documentation/devicetree/bindings/writing-bindings.rst#L42

Best regards,
Krzysztof

Hi, I did not understand the recommendation here.
Can I add "amlogic,meson-t7-uart" without Documentation changes? I think Yes, as I can see a few compatible strings in dts that don't exist anywhere else.

My idea here is to add "amlogic,meson-t7-uart" for future use if ever created, like if we find a bug in the future that is only relevant to T7 soc.
But for now, fallback to s4 uart, as it seems to be the same controller.

From Krzysztof said in the writing-bindings.rst, I am following the rules.

So, what's the path forward here?

Thanks
Lucas

#6 lore raw

Re: [PATCH v2 2/2] arm64: dts: meson-t7-a311d2-khadas-vim4: add initial device-tree

Quoted 22 lines · Lucas Tanure
Quoted 20 lines · Krzysztof Kozlowski
Quoted 17 lines · Yixun Lan

arch/arm64/boot/dts/amlogic/meson-t7.dtsi line 147

Quoted 9 lines
arch/arm64/boot/dts/amlogic/meson-t7.dtsi new file +9 -0
+            apb4: bus@fe000000 {
+                    compatible = "simple-bus";
+                    reg = <0x0 0xfe000000 0x0 0x480000>;
+                    #address-cells = <2>;
+                    #size-cells = <2>;
+                    ranges = <0x0 0x0 0x0 0xfe000000 0x0 0x480000>;
+
+                    uart_A: serial@78000 {
+                            compatible = "amlogic,meson-t7-uart",
                                              ~~~~~~~~~~~~~~~~~

if you introduce new compatible string, then at least you need to document it so Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml need to be updated

but my qeustion here, why bother introducing new compatible string if nothing changed with the compatible data? given the uart is same IP with g12a, can't we just use "amlogic,meson-g12-uart" for this? no only it will reduce the structure length of meson_uart_dt_match[], but also relieve maintainer's review burden?

Quoted 7 lines
Quoted 5 lines

https://elixir.bootlin.com/linux/v6.1-rc1/source/Documentation/devicetree/bindings/writing-bindings.rst#L42

Best regards,
Krzysztof

Hi, I did not understand the recommendation here.
Can I add "amlogic,meson-t7-uart" without Documentation changes?

No, you can't.

Quoted 2 lines

I think Yes, as I can see a few compatible strings in dts that don't exist anywhere else.

Aye, but we do not want to propagate that. New stuff should not be adding undocumented compatibles, and those that are undocumented should be documented.

Quoted 8 lines

My idea here is to add "amlogic,meson-t7-uart" for future use if ever created, like if we find a bug in the future that is only relevant to T7 soc.
But for now, fallback to s4 uart, as it seems to be the same controller.

Quoted 1 line

From Krzysztof said in the writing-bindings.rst, I am following the rules.

So, what's the path forward here?

You are following the rules from the dts point of view, you just need a 3rd patch in which you document the pattern you have added here in amlogic,meson-uart.yaml. It is probably something like:
+ - items:
+ - const: amlogic,meson-t7-uart
+ - const: amlogic,meson-s4-uart
But I have not tested that, I just wrote that in my mail client.

Cheers,
Conor.

maintainer
#7 lore raw

Re: [PATCH v2 2/2] arm64: dts: meson-t7-a311d2-khadas-vim4: add initial device-tree

Quoted 31 lines · Conor Dooley
Quoted 22 lines · Lucas Tanure
Quoted 20 lines · Krzysztof Kozlowski
Quoted 17 lines · Yixun Lan

arch/arm64/boot/dts/amlogic/meson-t7.dtsi line 147

Quoted 9 lines
arch/arm64/boot/dts/amlogic/meson-t7.dtsi new file +9 -0
+            apb4: bus@fe000000 {
+                    compatible = "simple-bus";
+                    reg = <0x0 0xfe000000 0x0 0x480000>;
+                    #address-cells = <2>;
+                    #size-cells = <2>;
+                    ranges = <0x0 0x0 0x0 0xfe000000 0x0 0x480000>;
+
+                    uart_A: serial@78000 {
+                            compatible = "amlogic,meson-t7-uart",
                                               ~~~~~~~~~~~~~~~~~

if you introduce new compatible string, then at least you need to document it so Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml need to be updated

but my qeustion here, why bother introducing new compatible string if nothing changed with the compatible data? given the uart is same IP with g12a, can't we just use "amlogic,meson-g12-uart" for this? no only it will reduce the structure length of meson_uart_dt_match[], but also relieve maintainer's review burden?

Quoted 7 lines
Quoted 5 lines

https://elixir.bootlin.com/linux/v6.1-rc1/source/Documentation/devicetree/bindings/writing-bindings.rst#L42

Best regards,
Krzysztof

Hi, I did not understand the recommendation here.
Can I add "amlogic,meson-t7-uart" without Documentation changes?

Quoted 8 lines

No, you can't.

Quoted 2 lines

I think Yes, as I can see a few compatible strings in dts that don't exist anywhere else.

Aye, but we do not want to propagate that. New stuff should not be adding undocumented compatibles, and those that are undocumented should be documented.

Documentation is ongoing, it takes time !

Neil

Quoted 20 lines
Quoted 9 lines

My idea here is to add "amlogic,meson-t7-uart" for future use if ever created, like if we find a bug in the future that is only relevant to T7 soc.
But for now, fallback to s4 uart, as it seems to be the same controller.

Quoted 1 line

From Krzysztof said in the writing-bindings.rst, I am following the rules.

So, what's the path forward here?

You are following the rules from the dts point of view, you just need a 3rd patch in which you document the pattern you have added here in amlogic,meson-uart.yaml. It is probably something like:

(quoted diff) +3 -0
+      - items:
+          - const: amlogic,meson-t7-uart
+          - const: amlogic,meson-s4-uart

But I have not tested that, I just wrote that in my mail client.

Cheers,
Conor.

#8 lore raw

Re: [PATCH v2 2/2] arm64: dts: meson-t7-a311d2-khadas-vim4: add initial device-tree

Quoted 7 lines · Neil Armstrong
Quoted 3 lines · Conor Dooley

Aye, but we do not want to propagate that. New stuff should not be adding undocumented compatibles, and those that are undocumented should be documented.

Documentation is ongoing, it takes time !

Don't worry, I wasn't trying to criticise, just pointing out the ideal situation.

#9 lore raw

Re: [PATCH v2 2/2] arm64: dts: meson-t7-a311d2-khadas-vim4: add initial device-tree

In reply to Lucas Tanure
Quoted 8 lines · Lucas Tanure
Quoted 6 lines

https://elixir.bootlin.com/linux/v6.1-rc1/source/Documentation/devicetree/bindings/writing-bindings.rst#L42

Best regards,
Krzysztof

Hi, I did not understand the recommendation here.
Can I add "amlogic,meson-t7-uart" without Documentation changes?

No, you cannot and checkpatch will ensure that.

Best regards,
Krzysztof