On 17.07.2010, at 11:53, Richard W.M. Jones wrote: > On Sat, Jul 17, 2010 at 10:50:59AM +0100, Richard W.M. Jones wrote: >> I understand from the git logs that fw_cfg was added because the old >> way was to load kernel & initrd into RAM directly, but this didn't >> work because SeaBIOS would clear the RAM, clobbering kernel & initrd. >> Could we change to loading these directly into RAM, and instead >> provide some indication to SeaBIOS so it doesn't clobber the RAM? I'm >> quite prepared to do the work, just wondering if there's something >> else I'm not getting about this. > > Or thinking around the subject: > > Change fw_cfg so that you send a command + a physical address, and > fw_cfg memcpy's the kernel / initrd / etc to that physical address. > Then linuxboot.bin doesn't have to do the manual copying. > > Or just change linuxboot.bin so it does 32 bit inl instructions, which > might at least be a bit faster ...
I don't see why it would be slow. ins should be emulated using coalesced mmio, no? Alex
