Puck.js: Allow flash memory protection to be overwridden with E.setFlags

espruino · Nov 27, 2017 · 5fedb5c · 5fedb5c
1 parent e9cb718
commit 5fedb5c
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Showing 5 changed files with 58 additions and 3 deletions.
diff --git a/ChangeLog b/ChangeLog
@@ -35,6 +35,7 @@
             nRF5x: jsvArrayPushAll memory leak fixes NRF.findDevices memory leak when services present
             jsvNewIterator now has an option to iterate over sparse arrays as if they weren't sparse
             Fixed some built-in functions that misbehaved when given sparse arrays
+            Puck.js: Allow flash memory protection to be overwridden with E.setFlags
 
      1v94 : Allow Espruino boards to reset straight out of the DFU Bootloader             
             Improvements in handling errors in code running in IRQs

diff --git a/scripts/hextojs.js b/scripts/hextojs.js
@@ -0,0 +1,49 @@
+#!/usr/bin/nodejs
+/* This is a big hack - we take a hex file and turn it into 
+Espruino commands that write the memory directly via JS. Can
+be used to do bootloader updates/etc.
+
+ASSUMES 4K PAGES
+*/
+
+var PAGESIZE = 4096;
+
+if (process.argv.length!=3) {
+  console.error("USAGE: hextojs.js inputfile.hex");
+  process.exit(1);
+}
+
+var inputFile = process.argv[2];
+
+var hex = require("fs").readFileSync(inputFile).toString().split("\n");
+var addrHi = 0;
+function parseLines(dataCallback) {
+  hex.forEach(function(hexline) {
+    var cmd = hexline.substr(1,2);
+    if (cmd=="02") {
+      var subcmd = hexline.substr(7,2);
+      if (subcmd=="02") addrHi = parseInt(hexline.substr(9,4),16) << 4; // Extended Segment Address
+      if (subcmd=="04") addrHi = parseInt(hexline.substr(9,4),16) << 16; // Extended Linear Address
+    } else if (cmd=="10") {
+      var addr = addrHi + parseInt(hexline.substr(3,4),16);
+      var data = [];
+      for (var i=0;i<16;i++) data.push(parseInt(hexline.substr(9+(i*2),2),16));
+      dataCallback(addr,data);
+    }
+  });
+}
+
+console.log('var f = require("Flash");');
+var erasedPages = [];
+parseLines(function(addr, data) {
+  var page = addr & ~(PAGESIZE-1);
+  if (erasedPages.indexOf(page) < 0) {
+    console.log('f.erasePage(0x'+page.toString(16)+');');
+    erasedPages.push(page);
+  }
+});
+parseLines(function(addr, data) {
+  // don't output stuff which is all 255
+  if (data.reduce((a,b)=>a+b) == data.length*255) return;    
+  console.log('f.write(['+data+'],0x'+addr.toString(16)+');');
+});
diff --git a/src/jsflags.h b/src/jsflags.h
@@ -18,11 +18,12 @@
 
 typedef enum {
   JSF_NONE,
-  JSF_DEEP_SLEEP          = 1<<0, // Allow deep sleep modes (also set by setDeepSleep)
-  JSF_PRETOKENISE         = 1<<1, // When adding functions, pre-minify them and tokenise reserved words
+  JSF_DEEP_SLEEP          = 1<<0, ///< Allow deep sleep modes (also set by setDeepSleep)
+  JSF_PRETOKENISE         = 1<<1, ///< When adding functions, pre-minify them and tokenise reserved words
+  JSF_UNSAFE_FLASH        = 1<<2, ///< Some platforms stop writes/erases to interpreter memory to stop you bricking the device accidentally - this removes that protection
 } PACKED_FLAGS JsFlags;
 
-#define JSFLAG_NAMES "deepSleep\0pretokenise\0"
+#define JSFLAG_NAMES "deepSleep\0pretokenise\0unsafeFlash\0"
 // NOTE: \0 also added by compiler - two \0's are required!
 
 extern volatile JsFlags jsFlags;

diff --git a/src/jswrap_espruino.c b/src/jswrap_espruino.c
@@ -700,6 +700,7 @@ Get Espruino's interpreter flags that control the way it handles your JavaScript
 
 * `deepSleep` - Allow deep sleep modes (also set by setDeepSleep)
 * `pretokenise` - When adding functions, pre-minify them and tokenise reserved words
+* `unsafeFlash` - Some platforms stop writes/erases to interpreter memory to stop you bricking the device accidentally - this removes that protection
 */
 /*JSON{
   "type" : "staticmethod",

diff --git a/targets/nrf5x/jshardware.c b/targets/nrf5x/jshardware.c
@@ -24,6 +24,7 @@
 #include "jsinteractive.h"
 #include "jswrap_io.h"
 #include "jswrap_date.h" // for non-F1 calendar -> days since 1970 conversion.
+#include "jsflags.h"
 
 #include "app_util_platform.h"
 #ifdef BLUETOOTH
@@ -1082,6 +1083,8 @@ void jshI2CRead(IOEventFlags device, unsigned char address, int nBytes, unsigned
 
 
 bool jshFlashWriteProtect(uint32_t addr) {
+  // allow protection to be overwritten
+  if (jsfGetFlag(JSF_UNSAFE_FLASH)) return false;
 #if PUCKJS
   /* It's vital we don't let anyone screw with the softdevice or bootloader.
    * Recovering from changes would require soldering onto SWDIO and SWCLK pads!