From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <39253D0B.F9AF86EE@raleigh.ibm.com> Date: Fri, 19 May 2000 09:09:31 -0400 From: Ralph Blach MIME-Version: 1.0 To: Daris A Nevil CC: Graham Stoney , Daniel Wu , linuxppc-embedded@lists.linuxppc.org Subject: Re: Porting LinuxPPC References: <20000519051051.236093C972@elph.research.canon.com.au> <39253A48.24B90117@snmc.com> Content-Type: text/plain; charset=us-ascii Sender: owner-linuxppc-embedded@lists.linuxppc.org List-Id: Daris, I disagree. I beleive that the Kernel load simply must be above 0x80000000. And I you want to put a lot of memory in one of these systems, it had better be movable down from 0xc0000000. On the IBM405gp and I assume, the 8xx systems, all of real memory is pinned into a to TLB's. Well, if one can't move the memory base down the the real memory available is from 0xc0000000 to whereve the IO starts. In the IBM405gp, this is at 0xe80000000. Chip Daris A Nevil wrote: > > Graham, > > I fell vicitm to the same mistake when I was writing boot code > for MPC850. I think adding that to the HOWTO is a great > idea. It would have save me 2 or 3 weeks of effort :-). > > Daris Nevil > SiSIC Inc/SNMC > > Graham Stoney wrote: > > > Hi Daniel, > > > > Daniel Wu writes: > > > I compiled the mpc8xx-2.2.13 sources using the attached configuration for a > > > MPC860T based board with 32MB of RAM. The output vmlinux file was downloaded > > > to the target using a BDM debugger. I changed the KERNELLOAD and KERNELBASE > > > to 1000000 instead of c0000000 so that the code is located at the start of > > > the 16MB region. > > > > To quote Grant Erickson in > > http://lists.linuxppc.org/listarcs/linuxppc-embedded/200001/msg00123.html: > > > > "You don't ever want to change KERNELLOAD or KERNELBASE, otherwise the > > virtual memory and MMU code will all break." > > > > This seems to be a common error, so I might add mention of it in the HOWTO. > > > > Regards, > > Graham > > > > -- > > Daris A Nevil > SiSIC, Inc., f.k.a. Simple Network Magic Corporation > 401 Kentucky Lane > McKinney, TX 75069 > 214-793-7757 > dnevil@snmc.com > ** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/