On Mon, Dec 03, 2007 at 09:50:21AM -0800, David Hawkins wrote: > Could you comment on a similar problem I had/have. > > I have a CPU with 1GB memory, and I use about 20 cPCI boards that > I give 8MB windows in PCI space. When I was trying to load my > custom driver with these boards, it would give me ioremap failures. > On a CPU that had 512MB of memory it worked fine. My 'temporary hack' > (which is still in place) for the 1GB CPUs was to add mem=512M (or > whatever it is) to the kernel command line. That was a good > enough fix at the time :) > > I have figured I was running out of page table entries or something > like that and was going to investigate one of these days ... > > However, perhaps it was that I was running out of address space. > But 0xC0000000 is at 3GB, I can't see that I would be triggering > an address space issue: > > 1GB = 0x40000000 > 20 x 8MB = 160MB > > But, I figured I'd ask anyway :)
Yes, same thing. There's N ways to fix it. But I see you're talking x86. > PS. The CPUs in this case are x86 based, while the PCI boards use > PLX-9054 bridges. I'm building new peripheral boards with MPC8349EAs > so this problem is going to rear its ugly head again soon, when > I work on the drivers for the new peripheral boards. You should be able to do something similar on x86 but the details are TBD. I would probably try to limit low memory to 512MB in the x86 case. -Matt _______________________________________________ Linuxppc-embedded mailing list Linuxppc-embedded@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-embedded
