drm/cirrus: kick out conflicting framebuffers earlier

It appears that grub2 will pass framebuffer info via EFI,
this causes the vram reserve to fail, so kick out efifb
earlier before cirrus loads.

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=826983
Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/gpu/drm/cirrus/cirrus_drv.c

@@ -35,9 +35,28 @@ static DEFINE_PCI_DEVICE_TABLE(pciidlist) = {
 	{0,}
 };
 
+
+static void cirrus_kick_out_firmware_fb(struct pci_dev *pdev)
+{
+	struct apertures_struct *ap;
+	bool primary = false;
+
+	ap = alloc_apertures(1);
+	ap->ranges[0].base = pci_resource_start(pdev, 0);
+	ap->ranges[0].size = pci_resource_len(pdev, 0);
+
+#ifdef CONFIG_X86
+	primary = pdev->resource[PCI_ROM_RESOURCE].flags & IORESOURCE_ROM_SHADOW;
+#endif
+	remove_conflicting_framebuffers(ap, "cirrusdrmfb", primary);
+	kfree(ap);
+}
+
 static int __devinit
 cirrus_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 {
+	cirrus_kick_out_firmware_fb(pdev);
+
 	return drm_get_pci_dev(pdev, ent, &driver);
 }