I am using DDR2 memory abstracted from me by a FPGA based memory controller. Hopefully, the hardware engineer is configuring it correctly. All register accesses are GPCM based. I build a version of u-boot with I-Cache turned off and it still failed. The Burst inhibit flag is turned on. I am able To do block copies with the assembly routines (memcpy, strcpy) which are faster than a C based for loop.

I am thinking of using the JTAG and copy some PPC code into RAM in a Infinite loop and run it manually.

Basically, some test to run some code from flash without relocation.

-- Atul

-----Original Message----- From: wd@denx.de [mailto:wd@denx.de] Sent: Monday, October 24, 2005 11:51 PM To: Sabharwal, Atul Cc: u-boot-users@lists.sourceforge.net Subject: Re: [U-Boot-Users] Running test code from RAM while having GOT pointing to flash

In message 4A062D477D842B4C8FC48EA5AF2D41F20152806A@us-bv-m23.global.tektronix.net you wrote:

My code seems to be crashing in the relocate_code routine while switching from flash to RAM. There was an address_probe fixup which was not enabled And I enabled it. So, the relocation table (GOT) gets copied successfully From flash to RAM but the code dies seomewhere between coping the fixups

I think you misunderstand the function of the GOT.

And the in_ram label. Somehow, on my BDI, it sees an exception and goes to the reset vector i.e 0x100.

See the FAQ at http://www.denx.de/wiki/view/DULG/UBootCrashAfterRelocation

My approach is to avoid the GOT stuff and write a test routine which is

The "GOT stuff" is known to work just fine. I suggest you focus on the remaining stuff, i. e. your SDRAM init sequence. Again, see the FAQ.

Best regards,

Wolfgang Denk