xref: /OK3568_Linux_fs/u-boot/board/freescale/p1_p2_rdb_pc/README (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593SmuzhiyunOverview
2*4882a593Smuzhiyun--------
3*4882a593SmuzhiyunP1_P2_RDB_PC represents a set of boards including
4*4882a593Smuzhiyun    P1020MSBG-PC
5*4882a593Smuzhiyun    P1020RDB-PC
6*4882a593Smuzhiyun    P1020RDB-PD
7*4882a593Smuzhiyun    P1020UTM-PC
8*4882a593Smuzhiyun    P1021RDB-PC
9*4882a593Smuzhiyun    P1024RDB
10*4882a593Smuzhiyun    P1025RDB
11*4882a593Smuzhiyun    P2020RDB-PC
12*4882a593Smuzhiyun
13*4882a593SmuzhiyunThey have similar design of P1020RDB but have DDR3 instead of DDR2. P2020RDB-PC
14*4882a593Smuzhiyunhas 64-bit DDR. All others have 32-bit DDR.
15*4882a593Smuzhiyun
16*4882a593SmuzhiyunKey features on these boards include:
17*4882a593Smuzhiyun    * DDR3
18*4882a593Smuzhiyun    * NOR flash
19*4882a593Smuzhiyun    * NAND flash (on RDB's only)
20*4882a593Smuzhiyun    * SPI flash (on RDB's only)
21*4882a593Smuzhiyun    * SDHC/MMC card slot
22*4882a593Smuzhiyun    * VSC7385 Ethernet switch (on P1020MBG, P1020RDB, & P1021RDB)
23*4882a593Smuzhiyun    * PCIE slot and mini-PCIE slots
24*4882a593Smuzhiyun
25*4882a593SmuzhiyunAs these boards use soldered DDR chips not regular DIMMs, an on-board EEPROM
26*4882a593Smuzhiyunis used to store SPD data. In case of absent or corrupted SPD, falling back
27*4882a593Smuzhiyunto timing data embedded in the source code will be used. Raw timing data is
28*4882a593Smuzhiyunextracted from DDR chip datasheet. Different speeds of DDR are supported with
29*4882a593Smuzhiyunthis approach. ODT option is forced to fit this set of boards, again because
30*4882a593Smuzhiyunthey don't have regular DIMMs.
31*4882a593Smuzhiyun
32*4882a593SmuzhiyunCONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS is defined as 5ms to meet specification
33*4882a593Smuzhiyunfor writing timing.
34*4882a593Smuzhiyun
35*4882a593SmuzhiyunVSC firmware Address is defined by default in config file for eTSEC1.
36*4882a593Smuzhiyun
37*4882a593SmuzhiyunSD width is based off DIP switch. DIP switch is detected on the
38*4882a593Smuzhiyunboard by reading i2c bus and setting the appropriate mux values.
39*4882a593Smuzhiyun
40*4882a593SmuzhiyunSome boards have QE module in the silicon (P1021 and P1025). QE and eLBC have
41*4882a593Smuzhiyunpins multiplexing. QE function needs to be disabled to access Nor Flash and
42*4882a593SmuzhiyunCPLD. QE-UEC and QE-UART can be enabled for linux kernel by setting "qe"
43*4882a593Smuzhiyunin hwconfig. In addition, QE-UEC and QE-TDM also have pins multiplexing, to
44*4882a593Smuzhiyunenable QE-TDM for linux kernel, set "qe;tdm" in hwconfig. Syntax is as below
45*4882a593Smuzhiyun
46*4882a593Smuzhiyun'setenv hwconfig qe' to enable QE UEC/UART and disable Nor-Flash/CPLD.
47*4882a593Smuzhiyun'setenv hwconfig 'qe;tdm'' to enalbe QE TDM and disable Nor-Flash/CPLD.
48