--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/python/stm32.py	Sun Jan 13 17:31:35 2013 +0100
@@ -0,0 +1,235 @@
+import time
+from devices import Device, registerDevice, STLinkException, Interface
+
+# F4 specifics:
+STM32_FLASH_BASE = 0x08000000
+STM32_SRAM_BASE  = 0x20000000
+
+FLASH_KEY1 = 0x45670123
+FLASH_KEY2 = 0xcdef89ab
+
+# flash registers:
+FLASH_F4_REGS_ADDR = 0x40023c00
+FLASH_F4_KEYR = FLASH_F4_REGS_ADDR + 0x04
+FLASH_F4_SR = FLASH_F4_REGS_ADDR + 0x0c
+FLASH_F4_CR = FLASH_F4_REGS_ADDR + 0x10
+
+FLASH_F4_CR_START = 16
+FLASH_F4_CR_LOCK = 31
+FLASH_CR_PG = 0
+FLASH_F4_CR_SER = 1
+FLASH_CR_MER = 2
+FLASH_F4_CR_SNB = 3
+FLASH_F4_CR_SNB_MASK = 0x38
+FLASH_F4_SR_BSY = 16
+
+def calculate_F4_sector(address):
+   """
+      from 0x8000000 to 0x80FFFFF
+      4 sectors of 0x4000 (16 kB)
+      1 sector of 0x10000 (64 kB)
+      7 of 0x20000 (128 kB)
+   """
+   sectorsizes = [0x4000] * 4 + [0x10000] + [0x20000] * 7
+   sectorstarts = []
+   a = STM32_FLASH_BASE
+   for sectorsize in sectorsizes:
+      sectorstarts.append(a)
+      a += sectorsize
+   # linear search:
+   sec = 0
+   while sec < len(sectorsizes) and address >= sectorstarts[sec]:
+      sec += 1
+   sec -= 1 # one back.
+   return sec, sectorsizes[sec]
+
+def calcSectors(address, size):
+   off = 0
+   sectors = []
+   while off < size:
+      sectornum, sectorsize = calculate_F4_sector(address + off)
+      sectors.append((sectornum, sectorsize))
+      off += sectorsize
+   return sectors
+
+@registerDevice(0x10016413)
+class Stm32F4(Device):
+   def __init__(self, iface):
+      super().__init__()
+      assert isinstance(iface, Interface)
+      self.iface = iface
+   # flashing commands:
+   def writeFlash(self, address, content):
+      # TODO:
+      flashsize = 0x100000 # fixed 1 MB for now..
+      print('WARNING: using 1 MB as flash size')
+      pagesize = 0x4000 # fixed for now!
+      print('warning: page size hardcoded')
+
+      # Check address range:
+      if address < STM32_FLASH_BASE:
+         raise STLinkException('Flashing below flash start')
+      if address + len(content) > STM32_FLASH_BASE + flashsize:
+         raise STLinkException('Flashing above flash size')
+      if address & 1 == 1:
+         raise STLinkException('Unaligned flash')
+      if len(content) & 1 == 1:
+         print('unaligned length, padding with zero')
+         content += bytes([0])
+      if address & (pagesize - 1) != 0:
+         raise STLinkException('Address not aligned with pagesize')
+      
+      # erase required space
+      sectors = calcSectors(address, len(content))
+      print('erasing {0} sectors'.format(len(sectors)))
+      for sector, secsize in sectors:
+         print('erasing sector {0} of {1} bytes'.format(sector, secsize))
+         self.eraseFlashSector(sector)
+
+      # program pages:
+      self.unlockFlashIf()
+      self.writeFlashCrPsiz(2) # writes are 32 bits aligned
+      self.setFlashCrPg()
+
+      print('writing {0} bytes'.format(len(content)), end='')
+      offset = 0
+      t1 = time.time()
+      while offset < len(content):
+         size = len(content) - offset
+         if size > 0x8000:
+            size = 0x8000
+
+         chunk = content[offset:offset + size]
+         while len(chunk) % 4 != 0:
+            print('padding chunk')
+            chunk = chunk + bytes([0])
+
+         # Use simple mem32 writes:
+         self.iface.write_mem32(address + offset, chunk)
+
+         offset += size
+         print('.', end='', flush=True)
+      t2 = time.time()
+      print('Done!')
+      print('Speed: {0} bytes/second'.format(len(content)/(t2-t1)))
+
+      self.lockFlash()
+
+      # verfify program:
+      self.verifyFlash(address, content)
+   def eraseFlashSector(self, sector):
+      self.waitFlashBusy()
+      self.unlockFlashIf()
+      self.writeFlashCrSnb(sector)
+      self.setFlashCrStart()
+      self.waitFlashBusy()
+      self.lockFlash()
+   def eraseFlash(self):
+      self.waitFlashBusy()
+      self.unlockFlashIf()
+      self.setFlashCrMer()
+      self.setFlashCrStart()
+      self.waitFlashBusy()
+      self.clearFlashCrMer()
+      self.lockFlash()
+   def verifyFlash(self, address, content):
+      device_content = self.readFlash(address, len(content))
+      ok = content == device_content
+      print('Verify:', ok)
+   def readFlash(self, address, size):
+      print('Reading {1} bytes from 0x{0:X}'.format(address, size), end='')
+      offset = 0
+      tmp_size = 0x1800
+      t1 = time.time()
+      image = bytes()
+      while offset < size:
+         # Correct for last page:
+         if offset + tmp_size > size:
+            tmp_size = size - offset
+
+         # align size to 4 bytes:
+         aligned_size = tmp_size
+         while aligned_size % 4 != 0:
+            aligned_size += 1
+
+         mem = self.iface.read_mem32(address + offset, aligned_size)
+         image += mem[:tmp_size]
+
+         # indicate progress:
+         print('.', end='', flush=True)
+
+         # increase for next piece:
+         offset += tmp_size
+      t2 = time.time()
+      assert size == len(image)
+      print('Done!')
+      print('Speed: {0} bytes/second'.format(size/(t2-t1)))
+      return image
+
+   def waitFlashBusy(self):
+      """ block until flash operation completes. """
+      while self.isFlashBusy():
+         pass
+   def isFlashLocked(self):
+      cr = self.readFlashCr()
+      mask = 1 << FLASH_F4_CR_LOCK
+      return cr & mask == mask
+   def unlockFlashIf(self):
+      if self.isFlashLocked():
+         self.iface.write_debug32(FLASH_F4_KEYR, FLASH_KEY1)
+         self.iface.write_debug32(FLASH_F4_KEYR, FLASH_KEY2)
+         if self.isFlashLocked():
+            raise STLinkException('Failed to unlock')
+   def lockFlash(self):
+      x = self.readFlashCr() | (1 << FLASH_F4_CR_LOCK)
+      self.writeFlashCr(x)
+
+   def readFlashSr(self):
+      return self.iface.read_debug32(FLASH_F4_SR)
+   def readFlashCr(self):
+      return self.iface.read_debug32(FLASH_F4_CR)
+   def writeFlashCr(self, x):
+      self.iface.write_debug32(FLASH_F4_CR, x)
+   def writeFlashCrSnb(self, sector):
+      x = self.readFlashCr()
+      x &= ~FLASH_F4_CR_SNB_MASK
+      x |= sector << FLASH_F4_CR_SNB
+      x |= 1 << FLASH_F4_CR_SER
+      self.writeFlashCr(x)
+   def setFlashCrMer(self):
+      x = self.readFlashCr()
+      x |= 1 << FLASH_CR_MER
+      self.writeFlashCr(x)
+   def setFlashCrPg(self):
+      x = self.readFlashCr()
+      x |= 1 << FLASH_CR_PG
+      self.writeFlashCr(x)
+   def writeFlashCrPsiz(self, n):
+      x = self.readFlashCr()
+      x &= (0x3 << 8)
+      x |= n << 8
+      self.writeFlashCr(x)
+   def clearFlashCrMer(self):
+      x = self.readFlashCr()
+      x &= ~(1 << FLASH_CR_MER)
+      self.writeFlashCr(x)
+   def setFlashCrStart(self):
+      x = self.readFlashCr()
+      x |= 1 << FLASH_F4_CR_START
+      self.writeFlashCr(x)
+   def isFlashBusy(self):
+      mask = 1 << FLASH_F4_SR_BSY
+      sr = self.readFlashSr()
+      # Check for error bits:
+      errorbits = {}
+      errorbits[7] = 'Programming sequence error'
+      errorbits[6] = 'Programming parallelism error'
+      errorbits[5] = 'Programming alignment error'
+      errorbits[4] = 'Write protection error'
+      errorbits[1] = 'Operation error'
+      #errorbits[0] = 'End of operation'
+      for bit, msg in errorbits.items():
+         if sr & (1 << bit) == (1 << bit):
+            raise STLinkException(msg)
+      return sr & mask == mask
+