On Sat, 2009-11-14 at 20:08 +0100, Joakim Tjernlund wrote: > Dan Malek <d...@embeddedalley.com> wrote on 14/11/2009 19:08:43: > > On Nov 14, 2009, at 2:42 AM, Joakim Tjernlund wrote: > > > > > ..... Avoid this by always pinning > > > kernel instruction TLB space. > > > > You may as well map the data space, too, since you have > > reserved the entries. Take advantage of that performance. > > Also, some processor variants have very few TLB entries, > > and may only reserve two entries (although the flag says > > reserve 4). Ensure there are sufficient resources to do > > what you want. This is the reason the option is configurable. > > Scott had some concerns about pinning the data space too. That is > is why I left the data TLB pinning behind the the config option. > > How to make better use of the remaining ITLB slots is tricky. > Somehow one would want to map at lest one to modules but I cannot see how.
No. If you use modules, you pay the price. Sane embedded solutions running in "tight" environments don't use modules :-) No point pinning TLB entries on the vmalloc space, really. What -might- be more useful is to look at Grant work on re-doing the early ioremap and providing a way to provide what the old io_block_mapping() did, but with dynamically chosen virtual addresses, to have a pinned entry covering most common IOs. Cheers, Ben. _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev