On Fri, 2010-05-28 at 11:18 -0500, Scott Wood wrote: > Only the physical address should depend on where IMMR is. We should > use > fixmap instead of an arbitrary address for the effective address. > There's a existing FIX_EARLY_DEBUG_BASE, but it's only 128 KiB so > we'll > have to either grow it, or map only a subset of IMMR. > > Plus, CONFIG_PPC_EARLY_DEBUG_CPM_ADDR points to the TX descriptor, > not > to the beginning of IMMR, so you should mask off the lower 20 bits > (the > offset is probably less than 64K, and the BAT might just ignore the > extra bits anyway, but why take chances?).
BAT has other advantages such as limiting TLB usage for things that are used often. I think we might want to revive Grant work on early ioremap here :-) Cheers, Ben. _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
