Re: [Qemu-devel] Re: EFI console stopped working in Qemu 0.14.0

[Isaku Yamahata]

Added CC to Tristan. I doubt that he is still interested in EFI, though.

On Thu, Mar 03, 2011 at 04:46:34PM +0900, Isaku Yamahata wrote:
> 
> Seabios has the patch to address the similar issue with
> the changeset of b82a1e49fc0e72fb9bf1a642d6aa707345b0f398,
> which enables memory/io unconditionally.
> 
> I suppose the EFI bios is very old so that it has the same issue.
> I think the following file is the one to modify.
> 
> efi-vfirmware.hg/edk2-sparse/EdkQemuPkg/Pei/BochsPciScan/BochsPciScan.c
> 
> thanks,
> 
> On Thu, Mar 03, 2011 at 08:43:11AM +0200, vagran wrote:
> > I am using TianoCore EFI by Tristan Gingold which is published
> > on http://wiki.qemu.org/download/efi-bios.tar.bz2. If you would try
> > to load it on Qemu 0.14.0 (built either for i386 or x86_64) you will
> > see nothing on VGA display or serial console. But it still will be
> > able to load OS after timeout if you have proper disk image.
> >> It seems your EFI BIOS doesn't enable memor, io or master bits
> >> in command register.
> >>   
> >>
> >> or disableintx.
> >>   
> > I have checked your guess and figured out that it works only
> > if both memory and io bits are not cleared. So the following
> > patch also works:
> > diff --git a/hw/pci.c b/hw/pci.c
> > index 8b76cea..bcf9b16 100644
> > --- a/hw/pci.c
> > +++ b/hw/pci.c
> > @@ -163,8 +163,9 @@ void pci_device_reset(PCIDevice *dev)
> >     pci_device_deassert_intx(dev);
> >     /* Clear all writeable bits */
> >     pci_word_test_and_clear_mask(dev->config + PCI_COMMAND,
> > -                                 pci_get_word(dev->wmask + PCI_COMMAND) |
> > -                                 pci_get_word(dev->w1cmask + PCI_COMMAND));
> > +                                 (pci_get_word(dev->wmask + PCI_COMMAND) |
> > +                                 pci_get_word(dev->w1cmask +  
> > PCI_COMMAND)) &
> > +                                 ~(PCI_COMMAND_IO | PCI_COMMAND_MEMORY));
> >     pci_word_test_and_clear_mask(dev->config + PCI_STATUS,
> >                                  pci_get_word(dev->wmask + PCI_STATUS) |
> >                                  pci_get_word(dev->w1cmask + PCI_STATUS));
> >
> > So probably the problem is in EFI BIOS. But I was not able to find
> > its source code. Anyone knows how is it built?
> >
> > Best regards,
> > Artyom.
> >
> >
> > Isaku Yamahata wrote:
> >> On Thu, Mar 03, 2011 at 12:03:53PM +0900, Isaku Yamahata wrote:
> >>   
> >>> Hi. Thank you for reporting.
> >>> Can you elaborate on the changeset that you pointed out and
> >>> your work around?
> >>>
> >>> Regarding to the changeset, it had the issue, but I suppose
> >>> 80376c3fc2c38fdd45354e4b0eb45031f35587ed fixed it.
> >>> Do you found any other issue?
> >>>
> >>> Regarding to your workaround, what was the problem?
> >>> What EFI BIOS are you using? Tiano-core derivatives that
> >>> Tristan Gingold worked on? Or other one?
> >>> It seems your EFI BIOS doesn't enable memor, io or master bits
> >>> in command register.
> >>>     
> >>
> >> or disableintx.
> >>
> >>   
> >>> If so, the issue is in the bios, not qemu.
> >>>
> >>> thanks,
> >>>
> >>> On Wed, Mar 02, 2011 at 11:27:31PM +0200, vagran wrote:
> >>>     
> >>>> vagran wrote:
> >>>>       
> >>>>> Hi,
> >>>>> I have noted that Qemu VGA and serial console with EFI BIOS 
> >>>>> stopped  working in
> >>>>> 0.14.0 (and in latest development snapshot is still not working). 
> >>>>>  Everything was
> >>>>> fine in 0.13.0. However EFI BIOS itself is able to load kernel if it was
> >>>>> properly configured on used disk image. The only effect is that   
> >>>>> neither VGA nor
> >>>>> serial console is not functioning. After short investigation I 
> >>>>> have  discovered
> >>>>> that this functionality was broken by this commit:
> >>>>>
> >>>>> commit 9bb3358627d87d8de25fb41b7276575539d799a7
> >>>>> Author: Isaku Yamahata <address@hidden>
> >>>>> Date:   Fri Nov 19 18:56:02 2010 +0900
> >>>>>
> >>>>> Do you have any idea how this change could affect EFI consoles?
> >>>>>
> >>>>>         
> >>>> After further investigation I have found that the following patch 
> >>>> provides
> >>>> a workaround for the problem, may be it could be useful for somebody who
> >>>> is more familiar with Qemu PCI code:
> >>>>
> >>>> diff --git a/hw/pci.c b/hw/pci.c
> >>>> index 8b76cea..06dd7ab 100644
> >>>> --- a/hw/pci.c
> >>>> +++ b/hw/pci.c
> >>>> @@ -162,9 +162,11 @@ void pci_device_reset(PCIDevice *dev)
> >>>>     pci_update_irq_status(dev);
> >>>>     pci_device_deassert_intx(dev);
> >>>>     /* Clear all writeable bits */
> >>>> +#if 0
> >>>>     pci_word_test_and_clear_mask(dev->config + PCI_COMMAND,
> >>>>                                  pci_get_word(dev->wmask + PCI_COMMAND) |
> >>>>                                  pci_get_word(dev->w1cmask + 
> >>>> PCI_COMMAND));
> >>>> +#endif
> >>>>     pci_word_test_and_clear_mask(dev->config + PCI_STATUS,
> >>>>                                  pci_get_word(dev->wmask + PCI_STATUS) |
> >>>>                                  pci_get_word(dev->w1cmask + 
> >>>> PCI_STATUS));
> >>>>
> >>>> Best regards,
> >>>> Artyom.
> >>>>
> >>>>       
> >>> -- 
> >>> yamahata
> >>>
> >>>     
> >
> 
> -- 
> yamahata
> 

-- 
yamahata