Hi, Bjorn, On Thu, Jan 6, 2022 at 8:07 AM Bjorn Helgaas <helgaas@xxxxxxxxxx> wrote: > > From: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> > > Previously we selected a device that owns the boot framebuffer as the > default device in vga_arb_select_default_device(). This was only done in > the vga_arb_device_init() subsys_initcall, so devices enumerated later, > e.g., by pcibios_init(), were not eligible. > > Fix this by moving the framebuffer device selection from > vga_arb_select_default_device() to vga_arbiter_add_pci_device(), which is > called after every PCI device is enumerated, either by the > vga_arb_device_init() subsys_initcall or as an ADD_DEVICE notifier. > > Note that if vga_arb_select_default_device() found a device owning the boot > framebuffer, it unconditionally set it to be the default VGA device, and no > subsequent device could replace it. > > Link: https://lore.kernel.org/r/20211015061512.2941859-7-chenhuacai@xxxxxxxxxxx > Based-on-patch-by: Huacai Chen <chenhuacai@xxxxxxxxxxx> > Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> > Cc: Bruno Prémont <bonbons@xxxxxxxxxxxxxxxxx> > --- > drivers/gpu/vga/vgaarb.c | 37 +++++++++++++++++-------------------- > 1 file changed, 17 insertions(+), 20 deletions(-) > > diff --git a/drivers/gpu/vga/vgaarb.c b/drivers/gpu/vga/vgaarb.c > index b0ae0f177c6f..aefa4f406f7d 100644 > --- a/drivers/gpu/vga/vgaarb.c > +++ b/drivers/gpu/vga/vgaarb.c > @@ -72,6 +72,7 @@ struct vga_device { > unsigned int io_norm_cnt; /* normal IO count */ > unsigned int mem_norm_cnt; /* normal MEM count */ > bool bridge_has_one_vga; > + bool is_framebuffer; /* BAR covers firmware framebuffer */ > unsigned int (*set_decode)(struct pci_dev *pdev, bool decode); > }; > > @@ -565,10 +566,9 @@ void vga_put(struct pci_dev *pdev, unsigned int rsrc) > } > EXPORT_SYMBOL(vga_put); > > -static void __init vga_select_framebuffer_device(struct pci_dev *pdev) > +static bool vga_is_framebuffer_device(struct pci_dev *pdev) > { > #if defined(CONFIG_X86) || defined(CONFIG_IA64) > - struct device *dev = &pdev->dev; > u64 base = screen_info.lfb_base; > u64 size = screen_info.lfb_size; > u64 limit; > @@ -583,15 +583,6 @@ static void __init vga_select_framebuffer_device(struct pci_dev *pdev) > > limit = base + size; > > - /* > - * Override vga_arbiter_add_pci_device()'s I/O based detection > - * as it may take the wrong device (e.g. on Apple system under > - * EFI). > - * > - * Select the device owning the boot framebuffer if there is > - * one. > - */ > - > /* Does firmware framebuffer belong to us? */ > for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) { > flags = pci_resource_flags(pdev, i); > @@ -608,13 +599,10 @@ static void __init vga_select_framebuffer_device(struct pci_dev *pdev) > if (base < start || limit >= end) > continue; > > - if (!vga_default_device()) > - vgaarb_info(dev, "setting as boot device\n"); > - else if (pdev != vga_default_device()) > - vgaarb_info(dev, "overriding boot device\n"); > - vga_set_default_device(pdev); > + return true; > } > #endif > + return false; > } > > static bool vga_arb_integrated_gpu(struct device *dev) > @@ -635,6 +623,7 @@ static bool vga_arb_integrated_gpu(struct device *dev) > static bool vga_is_boot_device(struct vga_device *vgadev) > { > struct vga_device *boot_vga = vgadev_find(vga_default_device()); > + struct pci_dev *pdev = vgadev->pdev; > > /* > * We select the default VGA device in this order: > @@ -645,6 +634,18 @@ static bool vga_is_boot_device(struct vga_device *vgadev) > * Other device (see vga_arb_select_default_device()) > */ > > + /* > + * We always prefer a firmware framebuffer, so if we've already > + * found one, there's no need to consider vgadev. > + */ > + if (boot_vga && boot_vga->is_framebuffer) > + return false; > + > + if (vga_is_framebuffer_device(pdev)) { > + vgadev->is_framebuffer = true; > + return true; > + } Maybe it is better to rename vga_is_framebuffer_device() to vga_is_firmware_device() and rename is_framebuffer to is_fw_framebuffer? Huacai > + > /* > * A legacy VGA device has MEM and IO enabled and any bridges > * leading to it have PCI_BRIDGE_CTL_VGA enabled so the legacy > @@ -1531,10 +1532,6 @@ static void __init vga_arb_select_default_device(void) > struct pci_dev *pdev, *found = NULL; > struct vga_device *vgadev; > > - list_for_each_entry(vgadev, &vga_list, list) { > - vga_select_framebuffer_device(vgadev->pdev); > - } > - > if (!vga_default_device()) { > list_for_each_entry_reverse(vgadev, &vga_list, list) { > struct device *dev = &vgadev->pdev->dev; > -- > 2.25.1 >
