drm/qxl: get vga ioports (fbf0a7f4) · Commits · 戴 / test

qxl has two modes: "native" (used by the drm driver) and "vga" (vga compatibility mode, typically used for boot display and firmware framebuffers). Accessing any vga ioport will switch the qxl device into vga mode. The qxl driver never does that, but other drivers accessing vga ports can trigger that too and therefore disturb qxl operation. So aquire the legacy vga ioports from vgaarb to avoid that. Reproducer: Boot kvm guest with both qxl and i915 vgpu, with qxl being first in pci scan order. v2: Skip this for secondary qxl cards which don't have vga mode in the first place (Frediano). Cc: Frediano Ziglio <fziglio@redhat.com> Signed-off-by:

Gerd Hoffmann <kraxel@redhat.com> Reviewed-by:

Dave Airlie <airlied@redhat.com> Link: http://patchwork.freedesktop.org/patch/msgid/20190805105401.29874-1-kraxel@redhat.com

drivers/gpu/drm/qxl/qxl_drv.c

+19 −1

Original line number	Diff line number	Diff line
		@@ -59,6 +59,11 @@ module_param_named(num_heads, qxl_num_crtc, int, 0400);
		static struct drm_driver qxl_driver;
		static struct pci_driver qxl_pci_driver;

		static bool is_vga(struct pci_dev *pdev)
		{
		return pdev->class == PCI_CLASS_DISPLAY_VGA << 8;
		}

		static int
		qxl_pci_probe(struct pci_dev pdev, const struct pci_device_id ent)
		{
		@@ -83,9 +88,17 @@ qxl_pci_probe(struct pci_dev pdev, const struct pci_device_id ent)
		if (ret)
		goto disable_pci;

		if (is_vga(pdev)) {
		ret = vga_get_interruptible(pdev, VGA_RSRC_LEGACY_IO);
		if (ret) {
		DRM_ERROR("can't get legacy vga ioports\n");
		goto disable_pci;
		}
		}

		ret = qxl_device_init(qdev, &qxl_driver, pdev);
		if (ret)
		goto disable_pci;
		goto put_vga;

		ret = qxl_modeset_init(qdev);
		if (ret)
		@@ -105,6 +118,9 @@ modeset_cleanup:
		qxl_modeset_fini(qdev);
		unload:
		qxl_device_fini(qdev);
		put_vga:
		if (is_vga(pdev))
		vga_put(pdev, VGA_RSRC_LEGACY_IO);
		disable_pci:
		pci_disable_device(pdev);
		free_dev:
		@@ -122,6 +138,8 @@ qxl_pci_remove(struct pci_dev *pdev)

		qxl_modeset_fini(qdev);
		qxl_device_fini(qdev);
		if (is_vga(pdev))
		vga_put(pdev, VGA_RSRC_LEGACY_IO);

		dev->dev_private = NULL;
		kfree(qdev);

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