Eric Lee / smarc-uboot

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d41ce506b   Eric Lee   Initial Release, ... 
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  By Thomas.Lange@corelatus.se 2004-Oct-05
  ----------------------------------------
  DbAu1xx0 are development boards from AMD containing
  an Alchemy AU1xx0 series cpu with mips32 core.
  Existing cpu:s are Au1000, Au1100, Au1500 and Au1550
  
  Limitations & comments
  ----------------------
  Support was originally big endian only.
  I have not tested, but several u-boot users report working
  configurations in little endian mode.
  
  I named the board dbau1x00, to allow
  support for all three development boards
  ( dbau1000, dbau1100 and dbau1500 ).
  Now there is a new board called dbau1550 also, which
  should be supported RSN.
  
  I only have a dbau1000, so my testing is limited
  to this board.
  
  The board has two different flash banks, that can
  be selected via dip switch. This makes it possible
  to test new bootloaders without thrashing the YAMON
  boot loader delivered with board.
  
  NOTE! When you switch between the two boot flashes, the
  base addresses will be swapped.
  Have this in mind when you compile u-boot. CONFIG_SYS_TEXT_BASE has
  to match the address where u-boot is located when you
  actually launch.
  
  Ethernet only supported for mac0.
  
  PCMCIA only supported for slot 0, only 3.3V.
  
  PCMCIA IDE tested with Sandisk Compact Flash and
  IBM microdrive.
  
  ###################################
  ########     NOTE!!!!!!   #########
  ###################################
  If you partition a disk on another system (e.g. laptop),
  all bytes will be swapped on 16bit level when using
  PCMCIA and running cpu in big endian mode!!!!
  
  This is probably due to an error in Au1000 chip.
  
  Solution:
  
  a) Boot via network and partition disk directly from
  dbau1x00. The endian will then be correct.
  
  b) Partition disk on "laptop" and fill it with all files
  you need. Then write a simple program that endian swaps
  whole disk,
  
  Example:
  Original "laptop" byte order:
  B0 B1 B2 B3 B4 B5 B6 B7 B8 B9...
  
  Dbau1000 byte order will then be:
  B1 B0 B3 B2 B5 B4 B7 B6 B9 B8...