On 25.06.2010 17:07, Matthieu Herrb wrote: > On Fri, Jun 25, 2010 at 03:25:10PM +0100, Stuart Henderson wrote: > >> On 2010/06/25 11:57, Carl-Daniel Hailfinger wrote: >> >>> Hi Jonathan, >>> >>> you're in CC of this mail because you sent the "unbreak pciutils" mail >>> to this list, and the failure mode is related. >>> http://marc.info/?l=openbsd-ports&m=126918139214769 >>> >> Hmmm... So why is PCIOCWRITE failing, even when securelevel is 0 and >> allowaperture=2... >> > > Probably because you do un-aligned PCI config space access. > Our /dev/pci only supports 32 bit wide read/write, aligned on 4 bytes > boundaries. > > If you need to write to PCI config space, you'll need a separate > kernel interface, with a high-level interface, so that you don't allow > random changes in the PCI config space from userland. >
Wouldn't allowing 16 bit and 8 bit reads/writes at native alignments in /dev/pci work for that? I could modify flashrom to use read/modify/write cycles to emulate 8/16 bit reads/writes with 32 bit reads/writes, but that may have undesirable side effects on some chipsets. > The rest of the discussion about not abusing the aperture driver for > this also stays. > I never fully understood how /dev/mem and the aperture driver are related. flashrom uses /dev/mem for memory access. The allowaperture stuff is something I guessed from reading various OpenBSD docs and mailing list posts. Regards, Carl-Daniel _______________________________________________ flashrom mailing list [email protected] http://www.flashrom.org/mailman/listinfo/flashrom
