Use custom script to set bootloader fuses

Makefile

@@ -64,6 +64,7 @@ b: burn
 l: logs
 
 burn: all
+	node scripts/dbgtool.js fuses
 	node scripts/dbgtool.js $(BUILD_PATH)/$(NAME).bin
 
 run: burn wait logs

scripts/dbgtool.js

@@ -21,6 +21,7 @@ function main() {
     if (/\.map$/.test(fileName)) mode = "map"
     else if (/\.bin$/.test(fileName)) mode = "bin"
     else if (/^server?$/.test(fileName)) mode = "server"
+    else if (/^fuses?$/.test(fileName)) mode = "fuses"
     else {
         console.log("usage: node " + process.argv[1] + " file.bin    # to burn")
         console.log("usage: node " + process.argv[1] + " file.map    # to dump logs")
@@ -76,7 +77,7 @@ function main() {
     if (mode == "map")
         cmd += `set M(0) 0; mem2array M 8 ${addr} ${logSize}; resume; parray M; shutdown`
     else
-        cmd += `at91samd bootloader 0; program ${fileName} verify reset; shutdown`
+        cmd += `program ${fileName} verify reset; shutdown`
 
     let args = ["-d2",
         "-s", openocdPath + "/share/openocd/scripts/",
@@ -88,7 +89,14 @@ function main() {
         args.pop()
     }
 
-    console.log("Starting " + openocdBin)
+    if (mode == "fuses") {
+        args.pop()
+        args.pop()
+        args.push("-f")
+        args.push("scripts/fuses.tcl")
+    }
+
+    console.log("Starting " + openocdBin + " " + args.join(" "))
     if (mode == "map")
         child_process.execFile(openocdBin, args, {
             maxBuffer: 1 * 1024 * 1024,

scripts/fuses.tcl

@@ -0,0 +1,61 @@
+# change forceupdate to 1 to update the fuses to values specified below
+set forceupdate 0
+set v0 0xD8E0C7FF
+set v1 0xFFFFFC5D
+
+init
+
+set CPU_MAX_ADDRESS 0xFFFFFFFF
+source [find bitsbytes.tcl]
+source [find memory.tcl]
+
+set fuse0 0x00804000
+set fuse1 0x00804004
+set nvmctrl 0x41004000
+
+set cmd_ear 0x5
+set cmd_pbc 0x44
+set cmd_wap 0x6
+
+proc cmd {C} {
+  global nvmctrl
+  global fuse0
+  memwrite32 [expr $nvmctrl + 0x1C] [expr $fuse0 / 2]
+  memwrite16 $nvmctrl [expr 0xA500 | $C]
+}
+
+set f0 [memread32 $fuse0]
+set f1 [memread32 $fuse1]
+
+puts "Fuses:"
+puts [format %x $f0]
+puts [format %x $f1]
+
+set updatefuses 0
+
+if { $forceupdate } then {
+  set updatefuses 1
+} else {
+  if { ($f0 & 0x7) != 0x7 } then {
+    set updatefuses 1
+    set v0 [expr $f0 | 0x7]
+    set v1 $f1
+  }
+}
+
+if { $updatefuses } then {
+  puts "*** Updating fuses! ***"
+  puts [format %x $v0]
+  puts [format %x $v1]
+  cmd $cmd_pbc
+  cmd $cmd_ear
+
+  memwrite32 $fuse0 $v0
+  memwrite32 $fuse1 $v1
+
+  cmd $cmd_wap
+
+  reset
+}
+
+shutdown