Re: [RFC V3 PATCH 1/7] arm64: dts: msm8992 SoC and LG Bullhead (Nexus 5X) support

On 2016-10-12 3:30 AM, Mark Rutland wrote:

On Wed, Oct 12, 2016 at 02:37:28AM -0700, Jeremy McNicoll wrote:

quoted

+/ {
+	model = "LGE MSM8992 BULLHEAD rev-1.01";
+	compatible = "qcom,msm8992";
+	qcom,board-id = <0xb64 0>;
+};

This last property doesn't seem to be documented or used in mainline.

What is it for?

Its required by the bootloader to select the correct blob.

quoted

+/ {
+	aliases {
+		serial0 = &blsp1_uart2;
+	};
+
+	chosen {
+		stdout-path = "serial0";
+	};

I'd recommend describing the configured rate, per
Documentation/devicetree/bindings/chosen.txt

Updated default serial settings have been changed as per V3
6/7 and the associated patch dropped. (6/7)

[...]

quoted

+/ {
+	model = "Qualcomm Technologies, Inc. MSM 8992";
+	compatible = "qcom,msm8992";
+	qcom,msm-id = <251 0>, <252 0>;
+	qcom,pmic-id = <0x10009 0x1000A 0x0 0x0>;

These last two are not documented, and not used in mainline.

What are they for?

They are explicitly needed by the bootloader.

quoted

+	memory {
+		#address-cells = <2>;
+		#size-cells = <2>;
+
+		device_type = "memory";
+		reg = <0 0 0 0>;

If this is filled in by the bootloader, please havea coment to that effect.

added comment

quoted

+		peripheral_mem: peripheral_region@0 {
+			linux,reserve-contiguous-region;
+			linux,reserve-region;
+			linux,remove-completely;
+			reg = <0 0x07400000 0 0x1c00000>;
+			label = "peripheral_mem";
+		};
+	};

What is this?

There aren't any sub-nodes of memory (iirc reserved-memory is a separate node),
an none of these 'liux,' prefixed properties exist in mainline.

dropped as its a relic of the past. (3.10)

[...]

quoted

+	timer {
+		compatible = "arm,armv8-timer";
+		interrupts = <1 2 0xf08>,
+				<1 3 0xf08>,
+				<1 4 0xf08>,
+				<1 1 0xf08>;
+		clock-frequency = <19200000>;
+	};

Why is the FW not programming the frequency register?

Not sure what the FW is doing as I don't have access to it.

quoted

+	clocks {
+		xo_board: xo_board {
+			compatible = "fixed-clock";
+			#clock-cells = <0>;
+			clock-frequency = <19200000>;
+		};
+
+		sleep_clk: sleep_clk {
+			compatible = "fixed-clock";
+			#clock-cells = <0>;
+			clock-frequency = <32768>;
+		};
+	};

Get rid of the clocks container node, and places these directly under the root node.

moved up, waaay up!

-jeremy

Thanks,
Mark.