1 files changed, 21 insertions, 11 deletions
diff --git a/target/linux/rdc/image/mkimg_bifferboard.py b/target/linux/rdc/image/mkimg_bifferboard.py
index 040c46274e..5444abebd1 100755
--- a/target/linux/rdc/image/mkimg_bifferboard.py
+++ b/target/linux/rdc/image/mkimg_bifferboard.py
@@ -1,21 +1,31 @@
 #!/usr/bin/env python
 
 """
-   Create firmware for 8MB Bifferboards
-   Firmware does not include the config blocks
-   Firmware starts just after config
+   Create firmware for 4/8MB Bifferboards, suitable for uploading using
+   either bb_upload8.py or bb_eth_upload8.py
 """
 
 import struct, sys
 
-kernel_extent = 0x200000
-config = 0x6000
+# Increase the kmax value if the script gives errors about the kernel being 
+# too large.  You need to set the Biffboot kmax value to the same value you
+# use here.
+kmax = 0x10
+
+# No need to change this for 4MB devices, it's only used to tell you if 
+# the firmware is too large!
+flash_size = 0x800000
+
+# This is always the same, for 1MB, 4MB and 8MB devices
+config_extent = 0x6000
+
+kernel_extent = kmax * 0x10000
 
 if __name__ == "__main__":
 
   if len(sys.argv) != 4:
-    print  "usage: mkimg_bifferboard.py <kernel> <64k JFFS> <output file>"
-    sys.exit(0)
+    print  "usage: mkimg_bifferboard.py <kernel> <rootfs> <output file>"
+    sys.exit(-1)
     
   bzimage = sys.argv[1]
   rootfs = sys.argv[2]
@@ -23,17 +33,17 @@ if __name__ == "__main__":
 
   # Kernel first
   fw = file(bzimage).read()
-  if len(fw) > (kernel_extent - config):
+  if len(fw) > (kernel_extent - config_extent):
     raise IOError("Kernel too large")
 
-  # Pad up to 0x200000
-  while len(fw) < (kernel_extent - config):
+  # Pad up to end of kernel partition
+  while len(fw) < (kernel_extent - config_extent):
     fw += "\xff"
 
   fw += file(rootfs).read()
 
   # Check length of total
-  if len(fw) > (0x800000 - 0x10000 - 0x6000):
+  if len(fw) > (flash_size - 0x10000 - config_extent):
     raise IOError("Rootfs too large")
 
   file(target,"wb").write(fw)