Tidy up linker script, allow F401 to use 3x16kB pages for storing program data

ChangeLog

@@ -10,6 +10,7 @@
             Merge fs_kill and file_kill to ensure that files always die before the filesystem
             Add `E.unmountSD()` to allow SD cards to be removed once they have been used
             Stop String.split("") adding an empty elementy to the array
+            Tidy up linker script, allow F401 to use 3x16kB pages for storing program data
 
      1v69 : Fix 1v67's regression of digitalPulse when doing lots of pulses
             Add configurable OneWire search command (for finding DS18B20s with alarm set)

boards/STM32F401CDISCOVERY.py

@@ -15,11 +15,11 @@
 
 import pinutils;
 info = {
- 'name' : "STM32F401 Discovery",
+  'name' : "STM32F401C Discovery",
   'link' :  [ "http://www.st.com/web/catalog/tools/FM116/SC959/SS1532/LN1848/PF259098" ],
   'default_console' : "EV_SERIAL2",
- 'variables' : 2650,
+  'variables' : 3040,
- 'binary_name' : 'espruino_%v_stm32f401Cdiscovery.bin',
+  'binary_name' : 'espruino_%v_stm32f401cdiscovery.bin',
 };
 chip = {
   'part' : "STM32F401VCT6",
@@ -33,6 +33,14 @@ chip = {
   'i2c' : 3,
   'adc' : 1,
   'dac' : 0,
+  'saved_code' : {
+    'address' : 0x08004000,
+    'page_size' : 16384, # size of pages
+    'page_number' : 1, # number of page we start at (0 based)
+    'pages' : 3, # number of pages we're using
+    'flash_available' : 256 # binary will have a hole in it, so we just want to test against full size
+  },
+  'place_text_section' : 0x08010000, # note flash_available above
 };
 # left-right, or top-bottom order
 board = {

scripts/build_linker.py

@@ -126,16 +126,19 @@ SECTIONS
   /* Then code, then constants */
   .text :
   {
+""")
+
+if "place_text_section" in board.chip:
+  codeOut("""    /* In the .py file we were told to place text here (to skip out what was before) */
+    . = ALIGN("""+hex(board.chip["place_text_section"]-FLASH_BASE)+"""); /* hacky! really want it absolute */
+""");
+
+codeOut("""
     . = ALIGN(4);
     *(.text)  
     *(.text*) 
     *(.rodata)  
     *(.rodata*) 
-    *(.glue_7)  
-    *(.glue_7t) 
-
-    KEEP (*(.init))
-    KEEP (*(.fini))
 
     . = ALIGN(4);
     _etext = .;
@@ -169,10 +172,8 @@ SECTIONS
 
     . = ALIGN(4);
     _ebss = .;         /* define a global symbol at bss end */
-    __bss_end__ = _ebss;
   } >RAM
 
-  PROVIDE ( end = _ebss );
   PROVIDE ( _end = _ebss );
 
   /* Remove stuff we don't want */

scripts/build_platform_config.py

@@ -76,21 +76,35 @@ if not LINUX:
   var_cache_size = var_size*variables
   flash_needed = var_cache_size + 4 # for magic number
   flash_page_size = 1024 # just a guess
+  flash_saved_code_sector = ""
   if board.chip["family"]=="STM32F1": flash_page_size = 1024 if "subfamily" in board.chip and board.chip["subfamily"]=="MD" else 2048
-  if board.chip["family"]=="STM32F2": flash_page_size = 128*1024
+  if board.chip["family"]=="STM32F2": 
+    flash_page_size = 128*1024
+    flash_saved_code_sector = 11
   if board.chip["family"]=="STM32F3": flash_page_size = 2*1024
-  if board.chip["family"]=="STM32F4": flash_page_size = 128*1024
+  if board.chip["family"]=="STM32F4": 
+    flash_page_size = 128*1024
+    flash_saved_code_sector = 11
   # F4 has different page sizes in different places
-  flash_pages = (flash_needed+flash_page_size-1)/flash_page_size
+  flash_saved_code_pages = (flash_needed+flash_page_size-1)/flash_page_size
   total_flash = board.chip["flash"]*1024
-  flash_available_for_code = total_flash - (flash_pages*flash_page_size)
+
+  if "saved_code" in board.chip:
+    flash_saved_code_start = board.chip["saved_code"]["address"]
+    flash_page_size = board.chip["saved_code"]["page_size"]
+    flash_saved_code_sector = board.chip["saved_code"]["page_number"]
+    flash_saved_code_pages = board.chip["saved_code"]["pages"]
+    flash_available_for_code = board.chip["saved_code"]["flash_available"]*1024
+  else:
+    flash_saved_code_start = "(FLASH_START + FLASH_TOTAL - FLASH_SAVED_CODE_LENGTH)"
+    flash_available_for_code = total_flash - (flash_saved_code_pages*flash_page_size)
     if has_bootloader: flash_available_for_code -= common.get_bootloader_size()
 
   print "Variables = "+str(variables)
   print "JsVar size = "+str(var_size)
   print "VarCache size = "+str(var_cache_size)
   print "Flash page size = "+str(flash_page_size)
-  print "Flash pages = "+str(flash_pages)
+  print "Flash pages = "+str(flash_saved_code_pages)
   print "Total flash = "+str(total_flash)
   print "Flash available for code = "+str(flash_available_for_code)
 
@@ -222,12 +236,13 @@ else:
   codeOut("#define JSVAR_CACHE_SIZE                "+str(variables)+" // Number of JavaScript variables in RAM")
   codeOut("#define FLASH_AVAILABLE_FOR_CODE        "+str(flash_available_for_code))
   codeOut("#define FLASH_PAGE_SIZE                 "+str(flash_page_size))
-  codeOut("#define FLASH_SAVED_CODE_PAGES          "+str(flash_pages))
+  codeOut("#define FLASH_SAVED_CODE_PAGES          "+str(flash_saved_code_pages))
   codeOut("#define FLASH_START                     "+hex(0x08000000))
+  if flash_saved_code_sector!="": codeOut("#define FLASH_SAVED_CODE_SECTOR                 "+str(flash_saved_code_sector))
   if has_bootloader: codeOut("#define BOOTLOADER_SIZE                 "+str(common.get_bootloader_size()))
   codeOut("")
   codeOut("#define FLASH_SAVED_CODE_LENGTH (FLASH_PAGE_SIZE*FLASH_SAVED_CODE_PAGES)")
-  codeOut("#define FLASH_SAVED_CODE_START (FLASH_START + FLASH_TOTAL - FLASH_SAVED_CODE_LENGTH)")
+  codeOut("#define FLASH_SAVED_CODE_START "+str(flash_saved_code_start))
   codeOut("#define FLASH_MAGIC_LOCATION (FLASH_SAVED_CODE_START + FLASH_SAVED_CODE_LENGTH - 4)")
   codeOut("#define FLASH_MAGIC 0xDEADBEEF")
 codeOut("");

targets/stm32/jshardware.c

@@ -2249,7 +2249,10 @@ void jshSaveToFlash() {
 
   jsiConsolePrint("Erasing Flash...");
 #if defined(STM32F2) || defined(STM32F4) 
-  FLASH_EraseSector(FLASH_Sector_11, VoltageRange_3);
+  for (i=0;i<FLASH_SAVED_CODE_PAGES;i++) {
+    FLASH_EraseSector(FLASH_Sector_0 + (FLASH_Sector_1-FLASH_Sector_0)*(FLASH_SAVED_CODE_SECTOR+i), VoltageRange_3); // a FLASH_Sector_## constant
+    jsiConsolePrint(".");
+  }
 #else
   /* Erase the FLASH pages */
   for(i=0;i<FLASH_SAVED_CODE_PAGES;i++) {