自 2025 年 3 月 27 日起,我們建議您使用 android-latest-release
而非 aosp-main
建構及貢獻 AOSP。詳情請參閱「Android 開放原始碼計畫變更」。
DTO 語法
透過集合功能整理內容
你可以依據偏好儲存及分類內容。
裝置樹狀架構來源 (DTS) 格式是裝置樹狀架構 (DT) 的文字表示法。裝置樹狀結構編譯器 (DTC) 會將這個格式轉換為二進位 DT,這是 Linux 核心預期的格式。
使用參照
DTC (裝置樹狀結構編譯器 + 重疊修補程式) 專案會在 dtc-format.txt 和 manual.txt 中說明 DTS 格式。如需瞭解 DTO 格式和規則,請參閱 dt-object-internal.txt。這些文件說明如何在疊加式資料表中使用節點 fragment@x
和語法 __overlay__
更新主資料表。例如:
/ {
fragment@0 {
target = <&some_node>;
__overlay__ {
some_prop = "okay";
...
};
};
};
不過,Google 強烈建議您不要使用 fragment@x
和語法 __overlay__
,而是改用參照語法。例如:
&some_node {
some_prop = "okay";
...
};
dtc
會使用語法 __overlay__
將參照語法編譯為與上述相同的物件。這個語法不會強制您為片段編號,因此您可以輕鬆讀取及寫入疊加 DTS。如果 dtc
不支援這類語法糖衣,請使用 AOSP 中的 DTC。
使用標籤
為允許未在編譯期間出現的節點有未定義的參照,重疊 DT .dts
檔案的標頭中必須有標記 /plugin/
。例如:
/dts-v1/;
/plugin/;
從這裡,您可以使用參照指定要重疊的節點,參照是前面帶有 & 符號 (&) 的絕對節點路徑。舉例來說,如果是主要 DT 中的 node@0
:
在主要 DT 中定義標籤 ... |
... 然後使用標籤。 |
[my_main_dt.dts]
/dts-v1/;
/ {
my_node: node@0 {
status = "disabled";
my_child: child@0 {
value = <0xffffffff>;
};
};
};
|
[my_overlay_dt.dts]
/dts-v1/;
/plugin/;
&my_node {
status = "okay";
};
&my_child {
value = <0x1>;
};
|
覆寫
如果參照目標屬性存在於主要 DT 中,則會在 DTO 之後覆寫;否則會附加。例如:
main.dts |
overlay.dts |
合併結果 |
[my_main_dt.dts]
/dts-v1/;
/ {
compatible = "corp,foo";
my_node: node@0 {
status = "disabled";
};
};
|
[my_overlay_dt.dts]
/dts-v1/;
/plugin/;
&my_node {
status = "okay";
};
|
/dts-v1/;
/ {
compatible = "corp,foo";
...
node@0 {
linux,phandle = <0x1>;
phandle = <0x1>;
status = "okay";
};
};
|
附加
如果參照目標屬性不在主要 DT 中,系統會在 DTO 後方附加該屬性。例如:
main.dts |
overlay.dts |
合併結果 |
[my_main_dt.dts]
/dts-v1/;
/ {
compatible = "corp,foo";
my_node: node@0 {
status = "okay";
};
};
|
[my_overlay_dt.dts]
/dts-v1/;
/plugin/;
&my_node {
new_prop = "bar";
};
|
/dts-v1/;
/ {
compatible = "corp,foo";
...
node@0 {
linux,phandle = <0x1>;
phandle = <0x1>;
status = "okay";
new_prop = "bar";
};
};
|
子節點
子節點語法的範例:
main.dts |
overlay.dts |
合併結果 |
[my_main_dt.dts]
/dts-v1/;
/ {
compatible = "corp,foo";
my_nodes: nodes {
compatible = "corp,bar";
node@0 {
status = "disabled";
};
};
};
|
[my_overlay_dt.dts]
/dts-v1/;
/plugin/;
&my_nodes {
new_prop1 = "abc";
node@0 {
status = "okay";
new_prop2 = "xyz";
};
};
|
/dts-v1/;
/ {
compatible = "corp,foo";
...
nodes {
linux,phandle = <0x1>;
phandle = <0x1>;
compatible = "corp,bar";
new_prop1 = "abc";
node@0 {
linux,phandle = <0x2>;
phandle = <0x2>;
status = "okay";
new_prop2 = "xyz";
};
};
};
|
這個頁面中的內容和程式碼範例均受《內容授權》中的授權所規範。Java 與 OpenJDK 是 Oracle 和/或其關係企業的商標或註冊商標。
上次更新時間:2025-08-21 (世界標準時間)。
[[["容易理解","easyToUnderstand","thumb-up"],["確實解決了我的問題","solvedMyProblem","thumb-up"],["其他","otherUp","thumb-up"]],[["缺少我需要的資訊","missingTheInformationINeed","thumb-down"],["過於複雜/步驟過多","tooComplicatedTooManySteps","thumb-down"],["過時","outOfDate","thumb-down"],["翻譯問題","translationIssue","thumb-down"],["示例/程式碼問題","samplesCodeIssue","thumb-down"],["其他","otherDown","thumb-down"]],["上次更新時間:2025-08-21 (世界標準時間)。"],[],[],null,["# DTO syntax\n\nDevice tree source (DTS) format is a textual representation of a device tree (DT).\nThe device tree compiler (DTC) processes this format into a binary DT,\nwhich is the form expected by the Linux kernel.\n\nUse references\n--------------\n\nThe [DTC](https://github.com/pantoniou/dtc)\n(device Tree compiler + overlay patches) project describes the DTS format in\n[dtc-format.txt](https://android.googlesource.com/platform/external/dtc/+/refs/heads/android16-release/Documentation/dts-format.txt)\nand\n[manual.txt](https://android.googlesource.com/platform/external/dtc/+/refs/heads/android16-release/Documentation/manual.txt).\nDTO format and rules are described in\n[dt-object-internal.txt](https://android.googlesource.com/platform/external/dtc/+/refs/heads/android16-release/Documentation/dt-object-internal.txt).\nThese documents describe how to update the main DT using node\n`fragment@x` and syntax `__overlay__` in overlay DT. For\nexample: \n\n```objective-c\n/ {\n fragment@0 {\n target = \u003c&some_node\u003e;\n __overlay__ {\n some_prop = \"okay\";\n ...\n };\n };\n};\n```\n\nHowever, Google strongly recommends you do **not** use\n`fragment@x` and syntax `__overlay__`, and instead use the\nreference syntax. For example: \n\n```scdoc\n&some_node {\n some_prop = \"okay\";\n ...\n};\n```\n\nReference syntax is compiled by `dtc` into the same object as the\nabove using syntax `__overlay__`. This syntax doesn't force you to\nnumber the fragments, enabling you to read and write overlay DTS easily. If your\n`dtc` doesn't support this syntactic sugar, use the\n[dtc\nin AOSP](https://android.googlesource.com/platform/external/dtc).\n\nUse labels\n----------\n\nTo allow undefined references to nodes not present at compilation time, the\noverlay DT `.dts` file must have a tag `/plugin/` in its\nheader. For example: \n\n```text\n/dts-v1/;\n/plugin/;\n```\n\nFrom here you can target the nodes to be overlaid using a reference, which is\nan absolute node path prefixed with an ampersand (\\&). For example, for\n`node@0` in the main DT:\n\n| Define labels in the main DT ... | ... then use the labels. |\n|-------------------------------------------------------------------------------------------------------------------------------------|-----------------------------------------------------------------------------------------------------------------|\n| ```ini [my_main_dt.dts] /dts-v1/; / { my_node: node@0 { status = \"disabled\"; my_child: child@0 { value = \u003c0xffffffff\u003e; }; }; }; ``` | ```ini [my_overlay_dt.dts] /dts-v1/; /plugin/; &my_node { status = \"okay\"; }; &my_child { value = \u003c0x1\u003e; }; ``` |\n\nOverride\n--------\n\nIf the reference target property exists in the main DT, it is overridden\nafter DTO; otherwise, it is appended. For example:\n\n| main.dts | overlay.dts | Merged Result |\n|-----------------------------------------------------------------------------------------------------------------|-----------------------------------------------------------------------------------|---------------------------------------------------------------------------------------------------------------------------------------|\n| ```ini [my_main_dt.dts] /dts-v1/; / { compatible = \"corp,foo\"; my_node: node@0 { status = \"disabled\"; }; }; ``` | ```ini [my_overlay_dt.dts] /dts-v1/; /plugin/; &my_node { status = \"okay\"; }; ``` | ```objective-c /dts-v1/; / { compatible = \"corp,foo\"; ... node@0 { linux,phandle = \u003c0x1\u003e; phandle = \u003c0x1\u003e; status = \"okay\"; }; }; ``` |\n\nAppend\n------\n\nIf the reference target property doesn't exist in the main DT, it is\nappended after DTO. For example:\n\n| main.dts | overlay.dts | Merged Result |\n|-------------------------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------|\n| ```ini [my_main_dt.dts] /dts-v1/; / { compatible = \"corp,foo\"; my_node: node@0 { status = \"okay\"; }; }; ``` | ```ini [my_overlay_dt.dts] /dts-v1/; /plugin/; &my_node { new_prop = \"bar\"; }; ``` | ```objective-c /dts-v1/; / { compatible = \"corp,foo\"; ... node@0 { linux,phandle = \u003c0x1\u003e; phandle = \u003c0x1\u003e; status = \"okay\"; new_prop = \"bar\"; }; }; ``` |\n\nChild nodes\n-----------\n\nExamples of child node syntax:\n\n| main.dts | overlay.dts | Merged Result |\n|------------------------------------------------------------------------------------------------------------------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|\n| ```ini [my_main_dt.dts] /dts-v1/; / { compatible = \"corp,foo\"; my_nodes: nodes { compatible = \"corp,bar\"; node@0 { status = \"disabled\"; }; }; }; ``` | ```ini [my_overlay_dt.dts] /dts-v1/; /plugin/; &my_nodes { new_prop1 = \"abc\"; node@0 { status = \"okay\"; new_prop2 = \"xyz\"; }; }; ``` | ```objective-c /dts-v1/; / { compatible = \"corp,foo\"; ... nodes { linux,phandle = \u003c0x1\u003e; phandle = \u003c0x1\u003e; compatible = \"corp,bar\"; new_prop1 = \"abc\"; node@0 { linux,phandle = \u003c0x2\u003e; phandle = \u003c0x2\u003e; status = \"okay\"; new_prop2 = \"xyz\"; }; }; }; ``` |"]]