2008-04-11 15:01:46 Mobile DDR Support
Kris Dickie (CANADA)
Message: 54115 I have a custom 548 board with mobile DDR on it. I can load a very stripped down u-boot (ie. just spi/eeprom/ and a few commands) into SPI flash and get it to boot, but it typically takes many resets, as u-boot often crashes. The same bootloader runs without any errors or crashes on the EZKIT.
I have narrowed the bootup crashes down to accesses to memory (ie. the mem operations env_relocate), and once finally running with a prompt, running mtest yields errors on almost every readback (usually off by just 1 bit).
I run a 40 MHz clock with VCO=13, CCLKDIV=1, SLCKDIV=4 (520 MHz CCLK and 130 MHz SCLK), and I know our local ADI rep. has said that mobile DDR is spec'ed out to run at only 80 MHz reliably, (anomaly 5000377) however I cannot get the processor to get past the initcode() stage when I have set SCLK= 80 MHz, you would think at least keeping the register defaults VCO=10, CCLKDIV=1, SCLKDIV=5 would yield something bootable past initcode(), but it does not, any ideas? I have tested two boards, and narrowed down that it is not a bad solder or pin producing the memory error. Also, I have tested the 548 EZKIT with SCLK= 80Mhz, and same thing, won't go past initcode().
Sorry, this maybe should be in the uboot thread, but others using mobile DDR may have similar issues in bootloader or kernel.
2008-04-11 17:16:09 Re: Mobile DDR Support
Kris Dickie (CANADA)
Message: 54122 Im guessing that the DDR refresh rates etc, programmed in DDRCTRL0 need to be updated when the SCLK changes, so I will test this out and inform. Also, I realized i missed setting bit 5 on EBIU_RSTCTL for mobile DDR operation.
2008-04-11 17:49:53 Re: Mobile DDR Support
Mike Frysinger (UNITED STATES)
Message: 54126 if memory isnt sane, then it doesnt matter terribly much how far u-boot makes it once it tries using external memory
i'd and a test similar to mtest at the end of the initcode and have it spit the results out the uart
2008-04-13 01:32:34 Re: Mobile DDR Support
Robin Getz (UNITED STATES)
Message: 54153 Kris:
Yeah, this is tracked in the bug tracker: