LuckFox Pico Pro/Max SD card writer from .env.txt

blkenvflash

#!/usr/bin/python3

# == BLKENVFLASH == written by Rene K. Mueller <[email protected]>
#
# Description:
#    Writes an image (.img) or to the SD card direct from existing .env.txt for LuckFox Pico Pro/Max
#
#       % ./blkenvflash disk.img
#       -- inquery with `lsblk` which device is your SD card resides --
#       % sudo dd if=disk.img of=/dev/sdX bs=1M; sync
#
#       -- or do in one step -- 
#       % sudo ./blkenflash /dev/sdX
#
# License: MIT
#
# History:
# 2024/06/18: after the hint by A. Schuetz https://github.com/LuckfoxTECH/luckfox-pico/issues/129 was able to make script functional
# 2024/06/10: start

import os, sys, re, subprocess, shutil
import atexit

VERSION = '0.0.1'

me = sys.argv.pop(0)
path = os.path.dirname(me)
me = os.path.basename(me)

step = 'sdcard'            # -- hard-codec to do one sdcard writing

if len(sys.argv) != 1:
   print(f'''USAGE {me} <file or device>
   examples:
      % ./{me} disk.img
      % lsblk     -- and check output on which /dev/sdX your SD card resides --
      % sudo dd if=disk.img of=/dev/sdX bs=1M; sync
      
      -- or in one step --
      % sudo ./{me} /dev/sdX
''')
   sys.exit(-1)
   
dev = sys.argv.pop(0)

print(f"== {me} {VERSION} ==")
print(f"writing to {dev}")
   

# -- a few helpers to en/decode nice numbers
def true_size(s):
   u = { 'B': 1, 'K': 1024, 'M': 1024*1024, 'G': 1024*1024*1024 }
   if m := re.search('(\d+)([BKMG])',s):
      return int(m.group(1)) * u[m.group(2)]
   return 0

def nice_size(n):
   u = { 'B': 1, 'K': 1024, 'M': 1024*1024, 'G': 1024*1024*1024 }
   for k,v in reversed(u.items()): 
      if n >= v and n % v == 0:
         return f"{n//v:,}{k}"
   return f"{n:,}B"

def cleanup():
   if os.path.exists(".env.txt.orig"):
      os.rename(".env.txt.orig",".env.txt")
   print("done.")

atexit.register(cleanup)
   
with open(".env.txt") as fh:
   env2 = [ ]
   for l in fh.readlines():
      if m := re.search('(blkdevparts|sd_parts)=(\w+)',l):
         _type = m.group(1)
         _dev = m.group(2)
         l = re.sub('blkdevparts=\w+:','',l)
         p = l.split(',')
         c_off = 0
         if step=='sdcard' and _dev == 'mmcblk1': 
            for e in p:
               #print(e)
               if (m := re.search('(\d+[KMG])@(\d+[KMG])\((\w+)\)',e)) or (m := re.search('(\d+[KMG])\((\w+)\)',e)):
                  if len(m.groups())==3:
                     size = true_size(m.group(1))
                     off = true_size(m.group(2))
                     name = m.group(3)
                  else:
                     size = true_size(m.group(1))
                     name = m.group(2)
                     off = 0
                  print(f"   {_dev}: {name}.img size:{size:,}/{nice_size(size)} (offset:{off:,}/{nice_size(off)})",end='')
                  if os.path.exists(f"{name}.img"):
                     size_ = os.path.getsize(f"{name}.img")           # -- actual size
                     print(f" imgsize:{size_:,} ({nice_size(size_)})")
                     if step=='sdcard':
                        # -- it seems the explicit `off` seems not taking effect?
                        cmd = ['dd',f"if={name}.img",f"of={dev}","bs=1k",f"seek={c_off//1024}"]
                        try:
                           res = subprocess.run(cmd,stdout=subprocess.DEVNULL,stderr=subprocess.DEVNULL,check=True)
                        except subprocess.CalledProcessError as e:
                           print(f"ERROR: {e}",e.stderr)
                           sys.exit(-1)
                     c_off += size
                  else:
                     print()
                     print(f"ERROR: '{name}.img' not found")
                     sys.exit(-1)
                     
         if _dev == 'mmcblk0':
            env2.append(l)

if step=='emmc':           # -- untested, not needed as 'upgrade_tool' does this already 
   shutil.copy(".env.txt",".env.txt.orig")
   with open(".env.txt","w") as fh:
      fh.write("\n".join(env2))

   # -- prepare upgrade_tool call to write to eMMC
   print(f"{path}/upgrade_tool")
   subprocess.run([f'{path}/upgrade_tool','uf','update.img'])   
               

what is supposed to be in .env.txt and why isnt it referenced in the official luckfox guide

for Everyone who googled Luckfox pico sth sd card flashing and found this page: https://wiki.luckfox.com/Luckfox-Pico/Luckfox-Pico-SD-Card-burn-image but no reference to the actual images mentioned, check the previous page, in my case that was https://wiki.luckfox.com/Luckfox-Pico/Luckfox-Pico-prepare and there is a google docs link to a 7zip archive (not zip, tarball or gzip for some reason)

once you download the files the script works incredibly well, beatifully programmed man, have you considered making a git repo with troubleshooting steps or documentation?