os: fix config.txt overload

Author: sonnyp

os/raspberry/config.ini

@@ -1,3 +1,4 @@
+# START PlanktoScope firmware config
 [all]
 bootloader_update=0
 disable_poe_fan=1
@@ -22,4 +23,5 @@ dtparam=sd_cqe=2
 # Enable SPI 2 - used for display
 dtoverlay=spi1-1cs,cs0_pin=4
 
+# STOP PlanktoScope firmware config
 [all]

os/raspberry/firmware.js

@@ -0,0 +1,74 @@
+#!/usr/bin/env node
+
+import { readFile, writeFile, appendFile } from "node:fs/promises"
+import { join } from "node:path"
+import { fileURLToPath } from "node:url"
+
+import { $ } from "execa"
+
+async function remountReadWrite(path) {
+  const { stdout } = await $`findmnt --json --target ${path}`
+  const result = JSON.parse(stdout)
+  const filesystem = result.filesystems[0]
+  const read_only = filesystem.options.split(",").includes("ro")
+
+  if (read_only) {
+    await $`mount -o remount,rw ${filesystem.target}`
+  }
+  return [read_only, filesystem]
+}
+
+async function remountReadWriteOnce(path, fn) {
+  const [was_read_only, filesystem] = await remountReadWrite(path)
+
+  try {
+    await fn()
+  } finally {
+    if (was_read_only) {
+      await $`mount -o remount,ro ${filesystem.target}`
+    }
+  }
+}
+
+const path = "/boot/firmware/"
+
+// Configure firmware
+// https://www.raspberrypi.com/documentation/computers/config_txt.html
+async function process_config() {
+  const path_config = join(path, "config.txt")
+
+  const content = await readFile(path_config, "utf8")
+  const include = await readFile(
+    fileURLToPath(import.meta.resolve("./config.ini")),
+    "utf8",
+  )
+
+  if (!content.trim().includes(include.trim())) {
+    await appendFile(path_config, include)
+  }
+}
+
+async function process_cmdline(path) {
+  // Disable the 4 Raspberry logo in the top left corner
+  // more space for kernel and system logs
+  const content = await readFile(path, "utf8")
+  const args = content.trim().split(" ")
+  if (!args.includes("logo.nologo")) {
+    args.push("logo.nologo")
+  }
+  await writeFile(path, args.join(" "))
+}
+
+if (import.meta.main) {
+  await remountReadWriteOnce(path, async () => {
+    await process_config()
+
+    for (const cmdline of ["cmdline.txt", "cmdline-A.txt", "cmdline-B.txt"]) {
+      try {
+        await process_cmdline(join(path, "cmdline.txt"))
+      } catch (err) {
+        if (err.code !== "ENOENT") throw err
+      }
+    }
+  })
+}

os/raspberry/firmware.sh

@@ -1,5 +1,6 @@
 setup:
-    ./firmware.sh
+    npm install
+    sudo NODE_DEBUG=execa ./firmware.js
     ./bootloader.sh
 
 test: