xref: /OK3568_Linux_fs/u-boot/board/pb1x00/README (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593SmuzhiyunBy Thomas.Lange@corelatus.se 2004-Oct-05
2*4882a593Smuzhiyun----------------------------------------
3*4882a593SmuzhiyunDbAu1xx0 are development boards from AMD containing
4*4882a593Smuzhiyunan Alchemy AU1xx0 series cpu with mips32 core.
5*4882a593SmuzhiyunExisting cpu:s are Au1000, Au1100, Au1500 and Au1550
6*4882a593Smuzhiyun
7*4882a593SmuzhiyunLimitations & comments
8*4882a593Smuzhiyun----------------------
9*4882a593SmuzhiyunSupport was originally big endian only.
10*4882a593SmuzhiyunI have not tested, but several u-boot users report working
11*4882a593Smuzhiyunconfigurations in little endian mode.
12*4882a593Smuzhiyun
13*4882a593SmuzhiyunI named the board dbau1x00, to allow
14*4882a593Smuzhiyunsupport for all three development boards
15*4882a593Smuzhiyun( dbau1000, dbau1100 and dbau1500 ).
16*4882a593SmuzhiyunNow there is a new board called dbau1550 also, which
17*4882a593Smuzhiyunshould be supported RSN.
18*4882a593Smuzhiyun
19*4882a593SmuzhiyunI only have a dbau1000, so my testing is limited
20*4882a593Smuzhiyunto this board.
21*4882a593Smuzhiyun
22*4882a593SmuzhiyunThe board has two different flash banks, that can
23*4882a593Smuzhiyunbe selected via dip switch. This makes it possible
24*4882a593Smuzhiyunto test new bootloaders without thrashing the YAMON
25*4882a593Smuzhiyunboot loader delivered with board.
26*4882a593Smuzhiyun
27*4882a593SmuzhiyunNOTE! When you switch between the two boot flashes, the
28*4882a593Smuzhiyunbase addresses will be swapped.
29*4882a593SmuzhiyunHave this in mind when you compile u-boot. CONFIG_SYS_TEXT_BASE has
30*4882a593Smuzhiyunto match the address where u-boot is located when you
31*4882a593Smuzhiyunactually launch.
32*4882a593Smuzhiyun
33*4882a593SmuzhiyunEthernet only supported for mac0.
34*4882a593Smuzhiyun
35*4882a593SmuzhiyunPCMCIA only supported for slot 0, only 3.3V.
36*4882a593Smuzhiyun
37*4882a593SmuzhiyunPCMCIA IDE tested with Sandisk Compact Flash and
38*4882a593SmuzhiyunIBM microdrive.
39*4882a593Smuzhiyun
40*4882a593Smuzhiyun###################################
41*4882a593Smuzhiyun########     NOTE!!!!!!   #########
42*4882a593Smuzhiyun###################################
43*4882a593SmuzhiyunIf you partition a disk on another system (e.g. laptop),
44*4882a593Smuzhiyunall bytes will be swapped on 16bit level when using
45*4882a593SmuzhiyunPCMCIA and running cpu in big endian mode!!!!
46*4882a593Smuzhiyun
47*4882a593SmuzhiyunThis is probably due to an error in Au1000 chip.
48*4882a593Smuzhiyun
49*4882a593SmuzhiyunSolution:
50*4882a593Smuzhiyun
51*4882a593Smuzhiyuna) Boot via network and partition disk directly from
52*4882a593Smuzhiyundbau1x00. The endian will then be correct.
53*4882a593Smuzhiyun
54*4882a593Smuzhiyunb) Partition disk on "laptop" and fill it with all files
55*4882a593Smuzhiyunyou need. Then write a simple program that endian swaps
56*4882a593Smuzhiyunwhole disk,
57*4882a593Smuzhiyun
58*4882a593SmuzhiyunExample:
59*4882a593SmuzhiyunOriginal "laptop" byte order:
60*4882a593SmuzhiyunB0 B1 B2 B3 B4 B5 B6 B7 B8 B9...
61*4882a593Smuzhiyun
62*4882a593SmuzhiyunDbau1000 byte order will then be:
63*4882a593SmuzhiyunB1 B0 B3 B2 B5 B4 B7 B6 B9 B8...
64