On Nov 6, 2008, at 3:59 PM, Scott Wood wrote: > Becky Bruce wrote: >> We don't want PHYS_64BIT on unconditionally. It has the effect of >> moving all the devices into high physical memory, which means you >> need a different Linux/dts. > > Another reason we should really be packaging the device trees with u- > boot. > >> I expect the normal case to be that it is off. Just those few >> customers that actually want to do this will use the PHYS_64BIT >> version. > > OK, though ideally it could be chosen dynamically based on how much > memory there is (in u-boot) or #address-cells (in linux). >
Well, in an ideal world, I'd have an IOMMU ;-) I left this build-time configurable because turning on PHYS_64BIT makes u-boot bigger, and there are always people who shout about that. There are also scenarios where you want to run with it enabled, and you don't have a lot of RAM. And, last but not least, I want to be consistent with linux, where 36-bit is a build-time configurable thing. Going to 36- bit requires that you know what you're doing - you need a 36b enabled kernel and .dts in order to boot - I don't want u-boot silently turning it on. At least not for a while. -Becky _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
