Hi,
i have a hardware which is very near to the yosemite board called JC-670. The yosemite board has 4 DDR chips and my hardware has only two chips (2*Micron 64V16M16 has 256Mbit...), because i need only 256MBit*2Chips=512MBit=64Mbyte.
It seem that i have problems with the DDR interface. I downloaded the u-boot bin file from the AMCC -> denx page, and programmed it into the flash on my hardware called JC-670. On the serial output i saw that the system starts up. But then it hangs...
Here is the first output hardware JC-670: =========================================== U-Boot 1.1.4-ga2c95a72 (Jul 28 2006 - 19:32:28)
CPU: AMCC PowerPC 440EP Rev. B at 666.666 MHz (PLB=266, OPB=133, EBC=133 MHz) I2C boot EEPROM enabled 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:
Software has not detected the DRAM !
Here is the second output hardware JC-670: ==========================================
U-Boot 1.1.4-ga2c95a72 (Jul 28 2006 - 19:32:28)
CPU: AMCC PowerPC 440EP Rev. B at 666.666 MHz (PLB=266, OPB=133, EBC=133 MHz) I2C boot EEPROM enabled 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: 256 MB
U-boot software has detected the DRAM's.
I can try this several times the difference is that sometimes i got the DRAM size(like first output) and somtimes not (like second output). Thats all. Must i change the u-boot code if i only use two DDR Chips ?
On the moment i can not generate a new u-boot bin , because it will not work with cygwin under windows.I tried it. And i'am not a linux expert, because of this i can not do this work under linux on the moment.
Has anybody an idea why sometimes the "256 MB" text will not come ?
For me it looks like the sdram_init() function in yosemite.c sometimes hangs.
Regards
Tobias