DTS Language Server

This LSP is intended to be used with DTS Devicetree Specification Release v0.4 (https://devicetree.org)

Table of Contents

• Features
  • Go to Definition
  • Go to Declarations
  • Go to References
  • Hover
  • Formatting
  • Semantic Tokens
  • Document Symbols
  • Workspace Symbols
  • Diagnostics
  • Completions
  • Refactoring
  • Code Actions
• Installation
• Usage
  • Zephyr
  • Linux
    • Devicetree-Org
  • Sample Editor configurations
    • kakoune
    • Neovim - lazygit
    • Helix
    • coc.nvim
    • Vim 9 - yegappan lsp

Features

Go to Definition

On node name/label reference; will list all the places where the node is altered. /delete-node/ cases are not listed. On property name; will list all the places where the property is assigned a value. Note: defining a property name with no assign (empty) is equal to assigning a truthful value and hence it will also be shown.

NOTE: If for example a node with name node1 has been created, then deleted, and then created again, depending on where the definition call is made in the file, in one case one will get the definition from before the delete keyword, and in the other case the definition from under the delete keyword.

Zephyr - DT_MACROS

You can also use Go to Definition on a selected number of DT_ APIs found in zephyr and get Hovers to help explain Node state or even DT_MACRO result for the current active Devicetree context

Go to Declarations

On node name/label reference; will list the first places where the node is created. On property name; will list the first places where the property is assigned a value for the first time. Note: defining a property name with no assign (empty) is equal to assigning a truthful value and hence it will also be shown.

NOTE: The declarations will stop at the definition, hence, if for example a node with name node1 has been created, then deleted, and then created again, depending on where the declarations call is made in the file, in one case one will get the declarations from before the delete keyword up to the delete keyword, and in the other case from the delete keyword (excluded) onwards.

Zephyr - DT_MACROS

You can also use Go to Declarations on a selected number of DT_ APIs found in zephyr and get Hovers to help explain Node state or even DT_MACRO result for the current active Devicetree context

Go to References - Find All References

• On node name/label reference; will list all the places where the node is used by name, label or in some path.
• On property name; will list all the places where the property referred to including /delete-property/.

NOTE: The references will stop at the definition, hence, if for example a node with name node1 has been created, then deleted, and then created again, depending on where the reference call is made in the file, in one case one will get the ones from before the delete keyword up to the delete keyword, and in the other case from the delete keyword (excluded) onwards.

Hover

On hover over the node name, a tooltip will show the final state of that node. If bindings are used it will also include the description from the binding files.

When hovering over a deleted state you can see the state of the item just before the delete action.

Zephyr - DT_MACROS

You can also hover on a selected number of DT_ APIs found in zephyr and get Hovers to help explain Node state or even DT_MACRO result for the current active Devicetree context

Formatting

This LSP follows the Zephyr Style Guide and is used in CI to validate all files upstream.

Semantic Tokens

Every element in the document will have semantic tokens to help highlight and color code the items.

Document Symbols

Every element in the document will have document symbols to help navigate the document in a tree format.

Workspace Symbols

You can also navigate the active context using workspace symbols.

Diagnostics

Reports generic syntax issues such as missing "," , "}" , ">" etc...

Reports when property has been replaced by a later definition and provides document link to where it has been redefined

Reports when node has been deleted and provides document link to where the delete was done

Reports when property has been deleted and provides document link to where it has been redefined

Reports label conflicts

Duplicate node name in the same node

Reports when deleting a node/property that does not exist

Reports CPreprocessor issues such as missing macro, invalid argument count etc.

Compares the node address and ensures that it matches the reg property, and that the reg values use the appropriate number of values as defined #address-cells

Reports property type mismatch errors

Reports prop-encoded-values errors when these need to follow some expected pattern e.g interrupts/nexus

Bus type validation when using Zephyr bindings

Completions

Completions are context aware of the document state on the line the action is requested.

Node path completion

Label reference completion reference node creation and property assignment

Delete Node:

Suggests appropriate type e.g. by reference or node name. Does not suggest keyword if no delete is possible.

Delete Property:

Suggests property names available in that context. Does not suggest keyword if no delete is possible.

Default values for standard types

Zephyr DT_MACRO Completion

Refactoring

Refactoring is possible on the following elements:

• Node names
• Node labels
• Property names

Given that in some cases the files included in a devicetree might come from an SDK which should not be edited, one can configure "lockRenameEdits" in the settings to lock refactoring from being permitted on any elements which would otherwise effect edits to the files listed in "lockRenameEdits".

Code Actions

• Adds missing syntax e.g. ';', '<', '>', ',' etc...
• Removes syntactically incorrect spaces:
  • Between node name, '@' and address
  • In node path reference
• Removes ';' when used without any statement
• Supports SourceFixAll/QuickFixes

Something else in mind?

Contributions are welcome or reach out on GitHub with requests.

Installation

The language server can be found on https://www.npmjs.com/package/devicetree-language-server.

To install run npm i -g devicetree-language-server

The LSP has only been tested with Node 20.

Usage

This extension needs a client that supports Configuration Capability. The format for the configuration setting is of the type Settings as shown below:

At the moment, this LSP only supports bindings for the Zephyr project and has experimental support for Devicetree-Org Bindings.

interface Context {
	ctxName?: string | number;
	cwd?: string;
	includePaths?: string[];
	dtsFile: string;
	overlays?: string[];
	bindingType?: BindingType;
	zephyrBindings?: string[];
	deviceOrgTreeBindings?: string[];
	deviceOrgBindingsMetaSchema?: string[];
	lockRenameEdits?: string[];
	formattingErrorAsDiagnostics?: boolean;
	compileCommands?: string;
}

interface Settings {
	cwd?: string;
	defaultBindingType?: BindingType;
	defaultZephyrBindings?: string[];
	defaultDeviceOrgTreeBindings?: string[];
	defaultDeviceOrgBindingsMetaSchema?: string[];
	defaultIncludePaths?: string[];
	contexts?: Context[];
	preferredContext?: string | number;
	defaultLockRenameEdits?: string[];
	defaultShowFormattingErrorAsDiagnostics?: boolean;
	autoChangeContext?: boolean;
	allowAdhocContexts?: boolean;
}

Zephyr configuration example

{
	"devicetree.cwd": "/User/workspace/zephyr",
	"devicetree.defaultIncludePaths": [
		"./zephyr/dts",
		"./zephyr/dts/arm",
		"./zephyr/dts/arm64/",
		"./zephyr/dts/riscv",
		"./zephyr/dts/common",
		"./zephyr/dts/vendor",
		"./zephyr/include",
		"./zephyr/dts/xtensa"
	],
	"devicetree.defaultBindingType": "Zephyr",
	"devicetree.defaultZephyrBindings": ["./zephyr/dts/bindings"],
	"devicetree.contexts": [
		{
			"devicetree.cwd": "/opt/nordic/ncs/v3.0.0",
			"bindingType": "Zephyr",
			"zephyrBindings": ["./zephyr/dts/bindings", "./nrf/dts/bindings"],
			"includePaths": [
				"./zephyr/dts",
				"./zephyr/dts/arm",
				"./zephyr/dts/arm64/",
				"./zephyr/dts/riscv",
				"./zephyr/dts/common",
				"./zephyr/dts/vendor",
				"./zephyr/include",
				"./zephyr/dts/xtensa"
			],
			"dtsFile": "./zephyr/boards/nordic/nrf52840dk/nrf52840dk_nrf52840.dts",
			"overlays": ["/User/project/myOverlay.overlay"]
		}
	]
}

Linux

{
	"devicetree.cwd": "/Users/user/Workspace/linux/",
	"devicetree.defaultIncludePaths": ["include"],
	"devicetree.defaultBindingType": "DevicetreeOrg",
	"devicetree.defaultDeviceOrgBindingsMetaSchema": [],
	"devicetree.defaultDeviceOrgTreeBindings": []
}

With Devicetree-Org Bindings

{
	"devicetree.cwd": "/Users/user/Workspace/linux/",
	"devicetree.defaultIncludePaths": ["include"],
	"devicetree.defaultBindingType": "DevicetreeOrg",
	"devicetree.defaultDeviceOrgBindingsMetaSchema": [
		"/Users/user/Workspace/linuxBindings/dt-schema/dtschema/meta-schemas" // https://github.com/devicetree-org/dt-schema/tree/main/dtschema/meta-schemas
	],
	"devicetree.defaultDeviceOrgTreeBindings": [
		"/Users/user/Workspace/linuxBindings/dt-schema/dtschema/schemas", // https://github.com/devicetree-org/dt-schema/tree/main/dtschema/schemas
		"/Users/user/Workspace/linux/Documentation/devicetree/bindings" // https://github.com/torvalds/linux/tree/master/Documentation/devicetree/bindings
	]
}

Note

Devicetree-Org bindings are experimental.

Sample Editor configurations

kakoune

Sample configuration in for kakoune with Zephyr 3.7.99 or later. Contribution by topisani

hook -group lsp-project-zephyr global BufSetOption filetype=(devicetree) %{
   eval %sh{
      root=$(eval "$kak_opt_lsp_find_root" .build_info.yml $(: kak_buffile))
      [ -e "$root/.build_info.yml" ] || exit 0

      settings=$(cat ".build_info.yml" | yq -c '{ "defaultIncludePaths": .cmake.devicetree."include-dirs", "contexts": [{ "bindingType": "Zephyr", "zephyrBindings": .cmake.devicetree."bindings-dirs", "includePaths": .cmake.devicetree."include-dirs", "dtsFile": .cmake.devicetree.files[0], "overlays": .cmake.devicetree.files[1:] }], "preferredContext": 0 } | { devicetree: {settings: {"_": {devicetree: .}}}}' | yj -jt | sed '/^\[devicetree\]$/d')

      cat <<EOF
      set-option buffer lsp_servers %{
         [devicetree]
         root = '$root'
         command = "npm"
         args = ["x", "--", "devicetree-language-server", "--stdio"]
         # command = "node"
         # args = ["/home/topisani/git/dts-lsp/server/dist/server.js", "--stdio"]
         settings_section = "_"

      $settings
      }
EOF
   }
}

Neovim - lazygit

Example setup using lazygit

return {
  "neovim/nvim-lspconfig",
  opts = function(_, opts)
    -- Don't let Mason try to handle this custom server
    opts.servers.devicetree_ls = nil

    local lspconfig = require("lspconfig")
    local configs = require("lspconfig.configs")
    local capabilities = vim.lsp.protocol.make_client_capabilities()

    -- Enable semantic tokens
    capabilities.textDocument = capabilities.textDocument or {}
    capabilities.textDocument.semanticTokens = {
      dynamicRegistration = false,
      requests = {
        range = false,
        full = true,
      },
       tokenTypes = {
        "namespace", "class", "enum", "interface", "struct", "typeParameter", "type",
        "parameter", "variable", "property", "enumMember", "decorator", "event", "function",
        "method", "macro", "label", "comment", "string", "keyword", "number", "regexp", "operator",
      },
      tokenModifiers = {
        "declaration", "definition", "readonly", "static", "deprecated", "abstract",
        "async", "modification", "documentation", "defaultLibrary",
      },
      formats = {'relative'}
    }

    -- Enable formatting
    capabilities.textDocument.formatting = {
      dynamicRegistration = false
    }

    -- Enable folding range support
    capabilities.textDocument.foldingRange = {
      dynamicRegistration = false,
      lineFoldingOnly = true,
    }

    if not configs.devicetree_ls then
      configs.devicetree_ls = {
        default_config = {
          cmd = { "devicetree-language-server", "--stdio" },
          filetypes = { "dts", "dtsi" },
          root_dir = lspconfig.util.root_pattern("zephyr", ".git", "."),
          settings = {
            devicetree = {
              defaultIncludePaths = {
                "./zephyr/dts",
                "./zephyr/dts/arm",
                "./zephyr/dts/arm64/",
                "./zephyr/dts/riscv",
                "./zephyr/dts/common",
				"./zephyr/dts/vendor",
                "./zephyr/include"
              },
              cwd = "${workspaceFolder}",
              defaultBindingType = "Zephyr",
              defaultZephyrBindings = {
                "./zephyr/dts/bindings"
              },
              autoChangeContext = true,
              allowAdhocContexts = true,
              contexts = {},
            },
          },
          capabilities = capabilities,
        },
      }
    end

    vim.notify("Custom devicetree_ls LSP loaded with semantic tokens & folding")

    -- Setup the LSP
    lspconfig.devicetree_ls.setup({
      capabilities = capabilities,
    })
  end,
}

Helix

Contribution by bextract

[[language]]
name = "devicetree"
language-servers = ["devicetree_ls"]

[language-server.devicetree_ls]
command = "devicetree-language-server"
args = ["--stdio"]
config = { devicetree = { cwd = "/home/bex/zephyrproject/", defaultIncludePaths = ["./zephyr/dts","./zephyr/dts/arm","./zephyr/dts/arm64","./zephyr/dts/riscv","./zephyr/dts/common","./zephyr/dts/vendor","./zephyr/include","./zephyr/dts/xtensa"], defaultBindingType = "Zephyr", defaultZephyrBindings = ["./zephyr/dts/bindings"], contexts = [] } }

coco nvim

{
  "suggest.completionItemKindLabels": {
    "keyword": "",
    "variable": "",
    "value": "",
    "operator": "Ψ",
    "constructor": "",
    "function": "ƒ",
    "reference": "渚",
    "constant": "",
    "method": "",
    "struct": "פּ",
    "class": "",
    "interface": "",
    "text": "",
    "enum": "",
    "enumMember": "",
    "module": "",
    "color": "",
    "property": "",
    "field": "料",
    "unit": "",
    "event": "鬒",
    "file": "",
    "folder": "",
    "snippet": "",
    "typeParameter": "",
    "default": ""
  },
  "diagnostic.errorSign": "❗",
  "diagnostic.warningSign": "💡",
  "diagnostic.infoSign": "💡",
  "diagnostic.hintSign": "💡",
  "diagnostic.signPriority": 100,
  "languageserver": {
    "devicetree_ls": {
      "command": "devicetree-language-server",
      "args": ["--stdio"],
      "filetypes": ["dts", "dtsi"],
      "rootPatterns": [".git"],
      "initializationOptions": {
        "AutomaticWorkspaceInit": true
      },
      "settings": {
        "devicetree": {
          "cwd": "/home/user/Workspace/Kernel/linux",
          "defaultIncludePaths": ["./include"],
          "defaultBindingType": "DevicetreeOrg",
          "contexts": []
        }
      }
    }
  }
}

Vim 9 - yegappan lsp

Contribution by jclsn

set encoding=utf-8
set nocompatible
colorscheme habamax

call plug#begin('$MYVIMDIR/plugged')
	Plug 'yegappan/lsp'
call plug#end()

let lspOpts = #{
        \   aleSupport: v:false,
        \   autoComplete: v:true,
        \   autoHighlight: v:false,
        \   autoHighlightDiags: v:true,
        \   autoPopulateDiags: v:false,
        \   completionMatcher: 'case',
        \   completionMatcherValue: 1,
        \   diagSignErrorText: '❗',
        \   diagSignHintText: '💡',
        \   diagSignInfoText: '💡',
        \   diagSignWarningText: '💡',
        \   diagSignPriority: {
        \       'Error': 100,
        \       'Warning': 99,
        \       'Information': 98,
        \       'Hint': 97
        \   },
        \   echoSignature: v:false,
        \   hideDisabledCodeActions: v:false,
        \   highlightDiagInline: v:true,
        \   hoverInPreview: v:false,
        \   ignoreMissingServer: v:false,
        \   keepFocusInDiags: v:true,
        \   keepFocusInReferences: v:true,
        \   completionTextEdit: v:true,
        \   diagVirtualTextAlign: 'above',
        \   diagVirtualTextWrap: 'default',
        \   noNewlineInCompletion: v:false,
        \   omniComplete: v:null,
        \   omniCompleteAllowBare: v:false,
        \   outlineOnRight: v:false,
        \   outlineWinSize: 20,
        \   popupBorder: v:true,
        \   popupBorderHighlight: 'Title',
        \   popupBorderHighlightPeek: 'Special',
        \   popupBorderSignatureHelp: v:false,
        \   popupHighlightSignatureHelp: 'Pmenu',
        \   popupHighlight: 'Normal',
        \   semanticHighlight: v:true,
        \   showDiagInBalloon: v:true,
        \   showDiagInPopup: v:true,
        \   showDiagOnStatusLine: v:false,
        \   showDiagWithSign: v:true,
        \   showDiagWithVirtualText: v:false,
        \   showInlayHints: v:false,
        \   showSignature: v:true,
        \   snippetSupport: v:false,
        \   ultisnipsSupport: v:false,
        \   useBufferCompletion: v:false,
        \   usePopupInCodeAction: v:false,
        \   useQuickfixForLocations: v:false,
        \   vsnipSupport: v:false,
        \   bufferCompletionTimeout: 100,
        \   customCompletionKinds: v:false,
        \   completionKinds: {},
        \   filterCompletionDuplicates: v:false,
        \   condensedCompletionMenu: v:false,
	\ }
autocmd User LspSetup call LspOptionsSet(lspOpts)

let lspServers = [#{
    \   name: 'devicetree_ls',
    \   filetype: ['dts', 'dtsi'],
    \   path: 'devicetree-language-server',
    \   args: ['--stdio'],
    \
    \   root_uri: {server_info -> lsp#utils#path_to_uri(
    \       lsp#utils#find_nearest_parent_file_directory(expand('%:p'), '.git', '.')
    \     )
    \   },
    \
    \   initializationOptions: #{
    \     settings: #{
    \       devicetree: #{
    \         cwd: getcwd(),
    \         defaultIncludePaths: [
    \           './include',
    \         ],
    \         defaultBindingType: 'DevicetreeOrg',
    \         contexts: []
    \       }
    \     }
    \   }
    \ }]

autocmd User LspSetup call LspAddServer(lspServers)

" Remap leader key to space
nnoremap <SPACE> <Nop>
let mapleader = " "
let maplocalleader = "-"

nnoremap <leader>ac :LspCodeAction<CR>
nnoremap <silent> <leader>pe :LspDiagPrev<CR>
nnoremap <silent> <leader>ne :LspDiagNext<CR>
nnoremap <silent> <leader>pd :LspPeekDefinition<CR>
nnoremap <silent> <leader>pdc :LspPeekDeclaration<CR>
nnoremap <silent> <leader>pr :LspPeekReferences<CR>
nnoremap <silent> <leader>ol :LspOutline<CR>
nnoremap <silent> <leader>rn :LspRename<CR>
nnoremap <leader>cl :LspCodeLens<CR>

function! s:SmartHover() abort
	let result = execute('LspHover')
	if result =~ 'Error'
		call feedkeys('K', 'n')
	endif
endfunction

nnoremap <silent> K :call <SID>SmartHover()<CR>

nnoremap <silent> gd :LspGotoDefinition<CR>
nnoremap <silent> gy :LspGotoTypeDef<CR>
nnoremap <silent> gi :LspGotoImpl<CR>
nnoremap <silent> gdc :LspGotoDeclaration<CR>

command! -nargs=0 -bar -range=% Format <line1>,<line2>LspFormat
set formatexpr=lsp#lsp#FormatExpr() " Map LspFormat to the gq command