Joshua, (did you ever watch some James Bond movie with idiom: "if I tell you, then I must kill you?) 👻
> AFAIK, Windows doesn't need a virgin state but the state the VBIOS / GOP > driver usually leaves the hardware in. Plus a Video BIOS Table (VBT) > with some hints about a board's specifics. What are these older boards? > Are you sure they support FLR? The first hints about FLR support I could > find were is a Haswell datasheet. It appears/shows to me from the Other Side of the Wall that Nico might be (somehow) correct. But I need to do verification on that as well. Please, stay tuned (hopefully)! Zoran On Thu, Mar 30, 2017 at 8:36 PM, Nico Huber <[email protected]> wrote: > Hi JP, > > On 30.03.2017 17:48, Joshua Pincus wrote: > > Hi Zoran, > > > > Thanks for your reply. > > > > My situation is this: When the VM guest comes up the first time from a > > system-level reset (aka power on), the Broadwell HD graphics device runs > > fine. I see basic VGA both before and during the boot of Windows. Once > > Windows boots, the HD graphics device is configured by Intel's driver > and I > > see hi-rez output. On a reboot of Windows within the VM, an FLR is > > issued. When the guest comes back up, no VGA. Windows does boot but > > provides no VGA output. If Windows needs to drop into VGA mode so that a > > user can access the real-mode functionality of the recovery console, > still > > no VGA. > > what kind of VM? what does it usually do when booting to support windows > (supposedly runs some BIOS / UEFI code)? Does that include running a > VBIOS or GOP UEFI driver? > > > > > It's only on Broadwell-based boards that we have this problem. If we > issue > > FLRs during the reset of the PCI bus for older Intel boards, no problem. > > We get VGA. Something involved with the FLR is messing up the state of > the > > hardware instead of actually returning the hardware to a virgin state, > akin > > to what you would get from a full system reset. > > AFAIK, Windows doesn't need a virgin state but the state the VBIOS / GOP > driver usually leaves the hardware in. Plus a Video BIOS Table (VBT) > with some hints about a board's specifics. What are these older boards? > Are you sure they support FLR? The first hints about FLR support I could > find were is a Haswell datasheet. > > Nico > >
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