As someone who has worked on the 8xx processors before, I went looking for the DER for the 8270 but was unable to find such a register. If someone can point me to such a register on the 8270, I would really appreciate it.
It looks like single-stepping doesn't work till later in the Kernel. Anyways, I found out after much debugging that it wasn't the first instruction that the break was occuring but the code made it all the way to the "cacheable_memzero" routine and fails in the "dcbz" instruction. The cpu gets reset as soon as I try to single-step this instruction. Any ideas as to why this is happening? --- Mark Chambers <mchambers at microfirst.com> wrote: > I'm not familiar with the 8270 per se, but on the > 8xx you've got this Debug > Enable Register (DER) where you set different bits > for things you want the > processor to jump into debug mode when they happen. > You might need to play > with that to get the BDI to catch whatever is > happening. It's probably set > in the BDI config file somewhere. > > ----- Original Message ----- > From: "annamaya" <annamaya at yahoo.com> > To: "annamaya" <annamaya at yahoo.com>; > <linuxppc-embedded at ozlabs.org> > Sent: Friday, January 21, 2005 4:20 PM > Subject: Re: Kernel booting issues on a MPC8270 > board > > > > I am sorry but I dont believe the "mfpvr" > instruction > > has anything to do with it. I thought removing it > was > > getting rid of the problem but I was wrong. The > board > > still gets reset when the very first instruction > is > > executed. I am stumped. > > > > --- annamaya <annamaya at yahoo.com> wrote: > > > > > I debugged this problem a little more and > realized > > > that the reset was happenning right after the > > > execution of the first kernel instruction at > > > 0x0000000c. The instruction at this location was > > > "mfpvr r28". I traced this back to a snippet of > code > > > that was dealing with pipeline depth issues on > the > > > MPC8260. Once I commented this code out, more > > > instructions were issued but the reboot happens > > > elsewhere. I am not able to pin-point the > location > > > of > > > the debug since my BDI fails to catch the reset > when > > > it happens. Can someone point me to the cause of > > > this > > > situation? Thanks in advance. > > > > > > --- annamaya <annamaya at yahoo.com> wrote: > > > > > > > I am trying to boot a mvista Linux Kernel ver. > > > > 2.4.20 > > > > on a MPC8270 board. I am using the > embed_config() > > > > in > > > > zImage to pass the board info since the > bootloader > > > > is > > > > not ppcboot. After the message, "Now booting > the > > > > kernel", the board just reboots, as if someone > > > > yanked > > > > the reset line. I have BDI hooked up but it > > > doesn't > > > > seem to catch the reset point in the code. And > I > > > am > > > > unable to trace this to anything in the code. > Any > > > > suggestions? Thanks in advance. > > > > > > > > > > > > > > > > __________________________________ > > > > Do you Yahoo!? > > > > Yahoo! Mail - now with 250MB free storage. > Learn > > > > more. > > > > http://info.mail.yahoo.com/mail_250 > > > > > _______________________________________________ > > > > Linuxppc-embedded mailing list > > > > Linuxppc-embedded at ozlabs.org > > > > > > > > > > https://ozlabs.org/mailman/listinfo/linuxppc-embedded > > > > > > > > > > > > > > > > > > > __________________________________ > > > Do you Yahoo!? > > > Read only the mail you want - Yahoo! Mail > SpamGuard. > > > > > > http://promotions.yahoo.com/new_mail > > > > > > > > > __________________________________________________ > > Do You Yahoo!? > > Tired of spam? Yahoo! Mail has the best spam > protection around > > http://mail.yahoo.com > > _______________________________________________ > > Linuxppc-embedded mailing list > > Linuxppc-embedded at ozlabs.org > > > https://ozlabs.org/mailman/listinfo/linuxppc-embedded > > __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com
