Differences

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--- linux_device_trees [2018/11/18 10:29] – [Proper use of .dtsi files] rpjday
+++ linux_device_trees [2018/12/11 13:03] (current) – [Internal wiki pages] rpjday
@@ Line 3: / Line 3: @@
 Stuff related to device trees and the Linux kernel, using examples from the current Linux kernel.
-To do:
+===== TO DO =====
   * overlays
+  * keywords (/plugin/, /memreserve/, /omit-if-no-ref/, /bits/)
+===== MISC (for now) =====
+  * "The unit-address must match the first address specified in the reg property of the node. If the node has no reg property, the @unit-address must be omitted and the node-name alone differentiates the node from other nodes at the same level in the tree. The binding for a particular bus may specify additional, more specific requirements for the format of reg and the unit-address."
 ===== Some links =====
@@ Line 46: / Line 51: @@
   * [[Device tree naming conventions]]
   * [[Proper device tree design]]
+  * [[Device tree standard properties]]
+  * [[Device tree node requirements]]
   * [[Comparing device trees with dtx_diff]]
+  * [[Hierarchical device files]]
-===== Proper device tree design =====
-==== Examples of /delete-node/ ====
-=== imx6dl-tx6s-8034.dts ===
-<file>
-#include "imx6dl.dtsi"
-#include "imx6qdl-tx6.dtsi"
-/ {
-        model = "Ka-Ro electronics TX6S-8034 Module";
-        compatible = "karo,imx6dl-tx6dl", "fsl,imx6dl";
-        aliases {
-                display = &display;
-                ipu1 = &ipu1;
-        };
-        cpus {
-                /delete-node/ cpu@1;
-        };
-</file>
-=== imx6q-utilite-pro.dts ===
-<file>
-#include <dt-bindings/input/input.h>
-#include "imx6q-cm-fx6.dts"
-/ {
-        model = "CompuLab Utilite Pro";
-        compatible = "compulab,utilite-pro", "compulab,cm-fx6", "fsl,imx6q";
- ...
-};
-/*
- * A single IPU is not able to drive both display interfaces available on the
- * Utilite Pro at high resolution due to its bandwidth limitation. Since the
- * tfp410 encoder is wired up to IPU1, sever the link between IPU1 and the
- * SoC-internal Designware HDMI encoder forcing the latter to be connected to
- * IPU2 instead of IPU1.
- */
-/delete-node/&ipu1_di0_hdmi;
-/delete-node/&hdmi_mux_0;
-/delete-node/&ipu1_di1_hdmi;
-/delete-node/&hdmi_mux_1;
-</file>
-==== Examples of /delete-property/ ====
-=== imx6qp.dtsi ===
-<file>
-#include "imx6q.dtsi"
-/ {
-        soc {
-        ...
-};
-&fec {
-        /delete-property/interrupts-extended;
-        interrupts = <0 118 IRQ_TYPE_LEVEL_HIGH>,
-                     <0 119 IRQ_TYPE_LEVEL_HIGH>;
-};
-</file>
-=== imx6ul-tx6ul-mainboard.dts ===
-<file>
-#include "imx6ul.dtsi"
-#include "imx6ul-tx6ul.dtsi"
-/ {
-        model = "Ka-Ro electronics TXUL-0010 Module on TXUL Mainboard";
-        compatible = "karo,imx6ul-tx6ul", "fsl,imx6ul";
-        aliases {
-                lcdif_24bit_pins_a = &pinctrl_disp0_3;
-                mmc0 = &usdhc1;
-                /delete-property/ mmc1;
-                serial2 = &uart3;
-                serial4 = &uart5;
-        };
-        /delete-node/ sound;
-};
-...
-&usdhc1 {
-        pinctrl-0 = <&pinctrl_usdhc1>;
-        non-removable;
-        /delete-property/ cd-gpios;
-        cap-sdio-irq;
-};
-&uart1 {
-        pinctrl-0 = <&pinctrl_uart1>;
-        /delete-property/ uart-has-rtscts;
-};
-&uart2 {
-        pinctrl-0 = <&pinctrl_uart2>;
-        /delete-property/ uart-has-rtscts;
-        status = "okay";
-};
-</file>