Re: [PATCH 3.13 073/187] x86, ia64: Move EFI_FB vga_default_device() initialization to pci_vga_fixup()

Kamal Mostafa
2014-09-16T13:31:23Z

On Tue, 2014-09-16 at 08:05 +0200, Bruno Prémont wrote:
> Hi Kamel,
>
> On Mon, 15 Sep 2014 15:08:03 -0700 Kamal Mostafa wrote:
> > 3.13.11.7 -stable review patch. If anyone has any objections, please let me know.
>
> As mentioned to Greg for 3.16 (and 3.14, 3.10) stable trees, please
> postpone this patch until its regression fix for dual-GPU Macs can be
> applied at the same time.

Thanks very much, Bruno. I've dropped this from the 3.13-stable queue
pending the regression fix.

-Kamal

> See
> https://patchwork.kernel.org/patch/4771201/
> as well as
> https://bugzilla.kernel.org/show_bug.cgi?id=84461
>
> Bruno
>
> > ------------------
> >
> > From: Kamal Mostafa <kamal@canonical.com>
> >
> > commit 20cde694027e7477cc532833e38ab9fcaa83fb64 upstream.
> >
> > Commit b4aa0163056b ("efifb: Implement vga_default_device() (v2)")
> > added efifb vga_default_device() so EFI systems that do not load
> > shadow VBIOS or setup VGA get proper value for boot_vga PCI sysfs
> > attribute on the corresponding PCI device.
> >
> > Xorg doesn't detect devices when boot_vga=0, e.g., on some EFI
> > systems such as MacBookAir2,1. Xorg detects the GPU and finds the
> > DRI device but then bails out with "no devices detected".
> >
> > Note: When vga_default_device() is set boot_vga PCI sysfs attribute
> > reflects its state. When unset this attribute is 1 whenever
> > IORESOURCE_ROM_SHADOW flag is set.
> >
> > With introduction of sysfb/simplefb/simpledrm efifb is getting
> > obsolete while having native drivers for the GPU also makes selecting
> > sysfb/efifb optional.
> >
> > Remove the efifb implementation of vga_default_device() and initialize
> > vgaarb's vga_default_device() with the PCI GPU that matches boot
> > screen_info in pci_fixup_video().
> >
> > [bhelgaas: remove unused "dev" in efifb_setup()]
> > Fixes: b4aa0163056b ("efifb: Implement vga_default_device() (v2)")
> > Tested-by: Anibal Francisco Martinez Cortina <linuxkid.zeuz@gmail.com>
> > Signed-off-by: Bruno Prémont <bonbons@linux-vserver.org>
> > Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
> > Acked-by: Matthew Garrett <matthew.garrett@nebula.com>
> > [ kamal: backport to 3.13-stable: context ]
> > Signed-off-by: Kamal Mostafa <kamal@canonical.com>
> > ---
> > arch/ia64/pci/fixup.c | 22 ++++++++++++++++++++++
> > arch/x86/include/asm/vga.h | 6 ------
> > arch/x86/pci/fixup.c | 21 +++++++++++++++++++++
> > drivers/video/efifb.c | 39
> > --------------------------------------- 4 files changed, 43
> > insertions(+), 45 deletions(-)
> >
> > diff --git a/arch/ia64/pci/fixup.c b/arch/ia64/pci/fixup.c
> > index 5dc969d..62fb9ba 100644
> > --- a/arch/ia64/pci/fixup.c
> > +++ b/arch/ia64/pci/fixup.c
> > @@ -5,6 +5,7 @@
> >
> > #include <linux/pci.h>
> > #include <linux/init.h>
> > +#include <linux/screen_info.h>
> >
> > #include <asm/machvec.h>
> >
> > @@ -38,6 +39,27 @@ static void pci_fixup_video(struct pci_dev *pdev)
> > if ((pdev->class >> 8) != PCI_CLASS_DISPLAY_VGA)
> > return;
> >
> > + if (!vga_default_device()) {
> > + resource_size_t start, end;
> > + int i;
> > +
> > + /* Does firmware framebuffer belong to us? */
> > + for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
> > + if (!(pci_resource_flags(pdev, i) &
> > IORESOURCE_MEM))
> > + continue;
> > +
> > + start = pci_resource_start(pdev, i);
> > + end = pci_resource_end(pdev, i);
> > +
> > + if (!start || !end)
> > + continue;
> > +
> > + if (screen_info.lfb_base >= start &&
> > + (screen_info.lfb_base +
> > screen_info.lfb_size) < end)
> > + vga_set_default_device(pdev);
> > + }
> > + }
> > +
> > /* Is VGA routed to us? */
> > bus = pdev->bus;
> > while (bus) {
> > diff --git a/arch/x86/include/asm/vga.h b/arch/x86/include/asm/vga.h
> > index 44282fb..c4b9dc2 100644
> > --- a/arch/x86/include/asm/vga.h
> > +++ b/arch/x86/include/asm/vga.h
> > @@ -17,10 +17,4 @@
> > #define vga_readb(x) (*(x))
> > #define vga_writeb(x, y) (*(y) = (x))
> >
> > -#ifdef CONFIG_FB_EFI
> > -#define __ARCH_HAS_VGA_DEFAULT_DEVICE
> > -extern struct pci_dev *vga_default_device(void);
> > -extern void vga_set_default_device(struct pci_dev *pdev);
> > -#endif
> > -
> > #endif /* _ASM_X86_VGA_H */
> > diff --git a/arch/x86/pci/fixup.c b/arch/x86/pci/fixup.c
> > index b046e07..4ee44d4 100644
> > --- a/arch/x86/pci/fixup.c
> > +++ b/arch/x86/pci/fixup.c
> > @@ -325,6 +325,27 @@ static void pci_fixup_video(struct pci_dev *pdev)
> > struct pci_bus *bus;
> > u16 config;
> >
> > + if (!vga_default_device()) {
> > + resource_size_t start, end;
> > + int i;
> > +
> > + /* Does firmware framebuffer belong to us? */
> > + for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
> > + if (!(pci_resource_flags(pdev, i) &
> > IORESOURCE_MEM))
> > + continue;
> > +
> > + start = pci_resource_start(pdev, i);
> > + end = pci_resource_end(pdev, i);
> > +
> > + if (!start || !end)
> > + continue;
> > +
> > + if (screen_info.lfb_base >= start &&
> > + (screen_info.lfb_base +
> > screen_info.lfb_size) < end)
> > + vga_set_default_device(pdev);
> > + }
> > + }
> > +
> > /* Is VGA routed to us? */
> > bus = pdev->bus;
> > while (bus) {
> > diff --git a/drivers/video/efifb.c b/drivers/video/efifb.c
> > index cd7c0df..201ab4f 100644
> > --- a/drivers/video/efifb.c
> > +++ b/drivers/video/efifb.c
> > @@ -19,8 +19,6 @@
> >
> > static bool request_mem_succeeded = false;
> >
> > -static struct pci_dev *default_vga;
> > -
> > static struct fb_var_screeninfo efifb_defined = {
> > .activate = FB_ACTIVATE_NOW,
> > .height = -1,
> > @@ -85,23 +83,10 @@ static struct fb_ops efifb_ops = {
> > .fb_imageblit = cfb_imageblit,
> > };
> >
> > -struct pci_dev *vga_default_device(void)
> > -{
> > - return default_vga;
> > -}
> > -
> > -EXPORT_SYMBOL_GPL(vga_default_device);
> > -
> > -void vga_set_default_device(struct pci_dev *pdev)
> > -{
> > - default_vga = pdev;
> > -}
> > -
> > static int efifb_setup(char *options)
> > {
> > char *this_opt;
> > int i;
> > - struct pci_dev *dev = NULL;
> >
> > if (options && *options) {
> > while ((this_opt = strsep(&options, ",")) != NULL) {
> > @@ -127,30 +112,6 @@ static int efifb_setup(char *options)
> > }
> > }
> >
> > - for_each_pci_dev(dev) {
> > - int i;
> > -
> > - if ((dev->class >> 8) != PCI_CLASS_DISPLAY_VGA)
> > - continue;
> > -
> > - for (i=0; i < DEVICE_COUNT_RESOURCE; i++) {
> > - resource_size_t start, end;
> > -
> > - if (!(pci_resource_flags(dev, i) &
> > IORESOURCE_MEM))
> > - continue;
> > -
> > - start = pci_resource_start(dev, i);
> > - end = pci_resource_end(dev, i);
> > -
> > - if (!start || !end)
> > - continue;
> > -
> > - if (screen_info.lfb_base >= start &&
> > - (screen_info.lfb_base +
> > screen_info.lfb_size) < end)
> > - default_vga = dev;
> > - }
> > - }
> > -
> > return 0;
> > }
> >
>