[U-Boot-Users] DDR SDRAM in DIMM module forYosemite-likePPC440EP board.

[Stefan Roese <sr@denx.de>]

On Tuesday 24 October 2006 06:14, Leonid wrote:
> Now I pass sdram0_mcsts status check (our HW folks said there was some
> clock marginality they fixed

Hopefully no further "marginality" problems are hidden.

> ) and proceed to program_tr1() function 
> which fails:
>
> U-Boot 1.1.4 (Oct 23 2006 - 20:28:01)
>
> CPU:   AMCC PowerPC 440EP Rev. B at 333.333 MHz (PLB=133, OPB=66, EBC=33
> MHz)
>        I2C boot EEPROM disabled
>        Internal PCI arbiter disabled, PCI async ext clock used
>        32 kB I-Cache 32 kB D-Cache
> Board: Yosemite - AMCC PPC440EP Evaluation Board
> I2C:   ready
> DRAM:  get_spd_info banks 1 Addresses: 0x51
> DIMM: slot 0: populated, bytes 128 size 8
> DIMM: slot 0: DDR SDRAM detected
> DIMM: 0 voltage level supported.
> DIMM: sdram0_cfg0 0x02000000 -> 0x00000000 -> 0x04000000.
> DIMM: sdram0_cfg1 0x00000000 -> 0x00000000.
> DIMM: sdram0_rtr 0x04100000.
> DIMM: sdram0_tr0 0x00894012 -> 0x00000000 -> 0x408A4012.
> DIMM: sdram0_b0cr 0x000C6001 base 0x00000000 size 0x10000000.
> DIMM: sdram0_b1cr 0x100C6001 base 0x10000000 size 0x10000000.
> DIMM: total size 0x20000000
> Starting memory test ....
> ERROR: Cannot determine a common read delay.
> ### ERROR ### Please RESET the board ###
>
> I tried several hardcoded tr1 values, it doesn't work either - code
> crashes on read/write attempts - I must investigate where exactly by
> reviewing assembler - GDB debugging on C level was not very helpful. But
> I believe it still same HW problem - situation became better, yet not
> good enough...

Did you try different DDR modules? I would suggest to start with small 
modules, perhaps only with one bank. For bigger modules you have to make sure 
that enough TLB entries are set up.

Best regards,
Stefan