On Tue, Oct 17, 2017 at 01:03:46PM +1100, Daniel Axtens wrote:
> Bjorn Helgaas <bhelg...@google.com> writes:
>
> > The default VGA device is normally set in vga_arbiter_add_pci_device() when
> > we call it for the first enabled device that can be accessed with the
> > legacy VGA resources ([mem 0xa0000-0xbffff], etc.)
> >
> > That default device can be overridden by an EFI device that owns the boot
> > framebuffer. As a fallback, we can also select a VGA device that can't be
> > accessed via legacy VGA resources, or a VGA device that isn't even enabled.
> >
> > Factor out this EFI and fallback selection from vga_arb_device_init() into
> > a separate vga_arb_select_default_device() function. This doesn't change
> > any behavior, but it untangles the "bridge control possible" checking and
> > messages from the default device selection.
> >
> > Tested-by: Zhou Wang <wangzh...@hisilicon.com> # D05 Hisi Hip07, Hip08
> > Signed-off-by: Bjorn Helgaas <bhelg...@google.com>
> > ---
> > drivers/gpu/vga/vgaarb.c | 57
> > ++++++++++++++++++++++++++++------------------
> > 1 file changed, 35 insertions(+), 22 deletions(-)
> >
> > diff --git a/drivers/gpu/vga/vgaarb.c b/drivers/gpu/vga/vgaarb.c
> > index 8035e38d5110..d35d6d271f3f 100644
> > --- a/drivers/gpu/vga/vgaarb.c
> > +++ b/drivers/gpu/vga/vgaarb.c
> > @@ -1402,29 +1402,14 @@ static struct miscdevice vga_arb_device = {
> > MISC_DYNAMIC_MINOR, "vga_arbiter", &vga_arb_device_fops
> > };
> >
> > -static int __init vga_arb_device_init(void)
> > +static void __init vga_arb_select_default_device(void)
> > {
> > - int rc;
> > struct pci_dev *pdev;
> > struct vga_device *vgadev;
> >
> > - rc = misc_register(&vga_arb_device);
> > - if (rc < 0)
> > - pr_err("error %d registering device\n", rc);
> > -
> > - bus_register_notifier(&pci_bus_type, &pci_notifier);
> > -
> > - /* We add all pci devices satisfying vga class in the arbiter by
> > - * default */
> > - pdev = NULL;
> > - while ((pdev =
> > - pci_get_subsys(PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID,
> > - PCI_ANY_ID, pdev)) != NULL)
> > - vga_arbiter_add_pci_device(pdev);
> > -
> > +#if defined(CONFIG_X86) || defined(CONFIG_IA64)
> > list_for_each_entry(vgadev, &vga_list, list) {
> > struct device *dev = &vgadev->pdev->dev;
> > -#if defined(CONFIG_X86) || defined(CONFIG_IA64)
> > /*
> > * Override vga_arbiter_add_pci_device()'s I/O based detection
> > * as it may take the wrong device (e.g. on Apple system under
> > @@ -1461,12 +1446,8 @@ static int __init vga_arb_device_init(void)
> > vgaarb_info(dev, "overriding boot device\n");
> > vga_set_default_device(vgadev->pdev);
> > }
> > -#endif
> > - if (vgadev->bridge_has_one_vga)
> > - vgaarb_info(dev, "bridge control possible\n");
> > - else
> > - vgaarb_info(dev, "no bridge control possible\n");
> > }
> > +#endif
> >
> > if (!vga_default_device()) {
> > list_for_each_entry(vgadev, &vga_list, list) {
> > @@ -1492,6 +1473,38 @@ static int __init vga_arb_device_init(void)
> > vga_set_default_device(vgadev->pdev);
> > }
> > }
> > +}
> > +
> > +static int __init vga_arb_device_init(void)
> > +{
> > + int rc;
> > + struct pci_dev *pdev;
> > + struct vga_device *vgadev;
> > +
> > + rc = misc_register(&vga_arb_device);
> > + if (rc < 0)
> > + pr_err("error %d registering device\n", rc);
> > +
> > + bus_register_notifier(&pci_bus_type, &pci_notifier);
> > +
> > + /* We add all PCI devices satisfying VGA class in the arbiter by
> > + * default */
> > + pdev = NULL;
> > + while ((pdev =
> > + pci_get_subsys(PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID,
> > + PCI_ANY_ID, pdev)) != NULL)
> > + vga_arbiter_add_pci_device(pdev);
> > +
> > + list_for_each_entry(vgadev, &vga_list, list) {
> > + struct device *dev = &vgadev->pdev->dev;
> > +
> > + if (vgadev->bridge_has_one_vga)
> > + vgaarb_info(dev, "bridge control possible\n");
> > + else
> > + vgaarb_info(dev, "no bridge control possible\n");
> > + }
>
> Initially I wondered if this info printk could be moved into
> vga_arbiter_check_bridge_sharing(), but it's been separated out since
> 3448a19da479b ("vgaarb: use bridges to control VGA routing where
> possible."), and upon closer examination, it seems you can't be sure a
> device doesn't share a bridge until the end of the process, so this is
> indeed correct.
>
> Everything else also looks good to me.
>
> Reviewed-by: Daniel Axtens <d...@axtens.net>
R-b for both patches? And ok with everyone if I pull this into drm-misc
for 4.15 (deadline is end of this week for feature-y stuff)?
Thanks, Daniel
--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch
