[U-Boot-Users] Software emulation exception on entry into RAM
I am implementing u-boot 1.0.2 on a custom 860P board and am getting a Software Emulation Exception (as reported by BDI2000) at the first access of RAM after code is copied to RAM.
The SDRAM setup was copied from a working PSOS+ load running on this board. Successful burst reads have been verified with a logic analyzer. I can't easily get access to the logic analyzer for debugging u-boot.
I have defined SRAM to be at 0x0 and I get the same results.
I know I am not using the CVS version of u-boot, I am using what was supplied w/ ELDK 3.0.
I have searched the list and have found cases where SDRAM initialization/burst read configurations have been blamed. Based on success w/ PSOS+, I don't think this is my problem.
Any ideas?
-Tom Laman
In message 41099EFD.7060702@rochester.rr.com you wrote:
I am implementing u-boot 1.0.2 on a custom 860P board and am getting a Software Emulation Exception (as reported by BDI2000) at the first access of RAM after code is copied
...whbich is most probably caused by incorrect initialization of the SDRAM.
The SDRAM setup was copied from a working PSOS+ load running on this board. Successful burst reads have been verified with a logic analyzer. I can't easily get access to the logic analyzer for debugging u-boot.
Did you verify with the LA which data was actually read from RAM after relocation?
I have defined SRAM to be at 0x0 and I get the same results.
I don't understand what you mean here.
I have searched the list and have found cases where SDRAM initialization/burst read configurations have been blamed. Based on success w/ PSOS+, I don't think this is my problem.
I still think it is. I have seen PSOS systems running happily on systems where a real OS would reliably crash because of memory problems.
Best regards,
Wolfgang Denk
participants (2)
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Thomas Laman -
Wolfgang Denk