On 01/15/2016 12:32 PM, Artyom Tarasenko wrote: >> If we ever properly implement a sun4v platform, we will implement the bulk of >> the hypervisor within qemu itself, for speed. At which point REAL will in >> fact >> undergo that final layer of translation exactly as expected. >> >> I think the naming is exactly correct, for the current sun4u implementation. > > But sun4u has neither real mode nor any ASI having "real" as a part of > its name, no?
Correct-ish. The ASI is called ASI_PHYS_USE_EC. But it has the same number as ASI_REAL. When there's a conflict I'm preferring the newer names. I think that it will cause less confusion in the end. > I thought it is much easier to implement the RA translation than the > hypervisor, > but maybe implementing the hypervisor is not as complex as I thought. > > Indeed, your variant would be more performant. > In any case it looks like an interesting challenge. The Alpha PALcode layer (equivalent to the sun4v hypervisor) is 99% implemented in qemu, and performs significantly better because of it. There are a few stubs in the qemu bios calling into some special helpers; I'd expect OpenBIOS for qemu to be the same. r~
