On 22/10/2019 02:32, Marty E. Plummer wrote: > On Mon, Oct 21, 2019 at 02:46:59PM +0200, Cédric Le Goater wrote: >> On 21/10/2019 07:34, David Gibson wrote: >>> On Sun, Oct 20, 2019 at 08:51:47AM +0200, Cédric Le Goater wrote: >>>> On 20/10/2019 08:28, David Gibson wrote: >>>>> >>>>> Ok. Note that the qemu emulated machine doesn't model the hardware >>>>> right down to the level of hostboot. That's wy we're just loading >>>>> skiboot and jumping straight into it usually. I guess clg's stuff to >>>>> load pnor images gets us a little closer to the hardware behaviour, >>>>> but I think it's still only a rough approximation. >>>> > On that note, is qemu-ppc64 currently capable of running LE firmware? My > coreboot port has currently reached a hitch in that part of the firmware > headers mapping stuff out is saved in LE mode while the cpu (real or emu) > is running in BE mode (FMAP headers are saved LE but CBFS headers are > saved BE) >>>> It's really tied to the OpenPOWER firmwares using the HIOMAP protocol >>>> to discuss with the BMC and load the flash. We could loosen how QEMU >>>> interprets the MTD device and use a property to inform QEMU that this >>>> is an OpenPOWER PNOR file and that skiboot and can be loaded from it. >>>> Something to discuss. >>> >>> Right. I'm guessing one significant issue here is that to fully model >>> the BMC, with *its* firmware and comms channels with the main host >>> would be quite a lot of work, hence cheating a bit to bypass that. >> >> In fact, we are not cheating that much. We use the IPMI BT interface of >> QEMU to handle the HIOMAP communication with the BMC and this model is >> quite precise. >> >> The mapping of the PNOR is simply mapped on the LPC FW address space. >> The underlying access are simplified because we don't have a LPC model >> but we could generate all the SPI transaction using the Aspeed models. >> I had experiments in that sense for P8. >> > Honestly getting the coreboot.rom into the lpc fw addr space in the same > way you do pnor images would be a useful sim, as that's more or less how > its going to be done on existing hardware.
That is covered by patch 'ppc/pnv: Add HIOMAP commands' in the series I sent. C.