Hi Dave
Dave Littell wrote:
Hi all,
I'm working on an AMCC PPC440EPx platform that is similar to the AMCC
We have also a PPC440EPx based board (HCU5, in the u-boot tree).
Sequoia under U-Boot 1.3.1. I've copied the Sequoia board and configuration as a starting point, but I've run into a problem with the size of the flash-based portion of U-Boot. I've added code to initdram() that results in the addition of 3-4 dozen assembly instructions. Now the board hangs after a very few tftp (or even ping) commands. However, if I remove the code I added, there's no problem with tftp, etc. I've narrowed it down to the point where I can make the difference between a working and non-working load by adding just a few instructions to initdram(). Some boundary or limit is being crossed somewhere...
Recently, (the last few weeks) we did run in a similar problem that loading the vxWorks image hangs in the middle of the tftp transfer. Some boards have it never, newer ones more often and some have it more or less often depending on the physical locatian, e.g. they show the behaviour at my workplace but not at the workplace of my co-worker. Sometimes it has this behaviour just at the beginning and after a few minutes it loads the whole image without problem.
I am investigating the problem. It seems that sometimes I get a IVOR1 (Machine check) -exception. But unfortunatly I do not have at the moment a setup where I can easily reproduce the problem.
This may be a problem which may or may not be related to yours.
Also be warned that the PPC440EPx is a very powerful CPU where a lot of parallelisme exists. We did run into subtle, hard to find problems because the CPU did reorder read/write accesses to different addreses. Therefore if you access somewhere memory based CPLD/MACH or other registers always use the in_/out_<xx> macros.
Best regards
Niklaus