[EMAIL PROTECTED] wrote: > My main queries are: 1) Why did changing the kernel base address to > 0x80000000 make the system unstable?
Because there's a bug somewhere. :-) > 2) Currently IMMRBAR has the same physical and virtual address. Does > this need to be the case? No, and it is not done that way in arch/powerpc. > 3) Why the kernel is designed to run at 0xc0000000? My guess is because it's a number that Linus pulled out of thin air back when a gig of RAM was unimaginably large. :-P > This seems to leave only 1GB of addressing space for all the > physically addressable memory (RAM + ioremapped + registers), while > reserving 3GB of space for user processes. The 3GB is presumably > mostly unusable on a system without a large amount of swap, as the > 1GB limit on memory will prevent much more than that being available > for user space. Well, it's also useful for sparse mappings, but I agree that the 3/1 split is probably suboptimal for most workloads. -Scott _______________________________________________ Linuxppc-embedded mailing list Linuxppc-embedded@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-embedded
