Add virtio gpu driver.

This patch adds a kms driver for the virtio gpu.  The xorg modesetting
driver can handle the device just fine, the framebuffer for fbcon is
there too.

Qemu patches for the host side are under review currently.

The pci version of the device comes in two variants: with and without
vga compatibility.  The former has a extra memory bar for the vga
framebuffer, the later is a pure virtio device.  The only concern for
this driver is that in the virtio-vga case we have to kick out the
firmware framebuffer.

Initial revision has only 2d support, 3d (virgl) support requires
some more work on the qemu side and will be added later.

Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>

1 files changed, 91 insertions, 0 deletions

diff --git a/drivers/gpu/drm/virtio/virtgpu_drm_bus.c b/drivers/gpu/drm/virtio/virtgpu_drm_bus.c
new file mode 100644
index 000000000000..f4ec816e9468
--- /dev/null
+++ b/drivers/gpu/drm/virtio/virtgpu_drm_bus.c
@@ -0,0 +1,91 @@
+/*
+ * Copyright (C) 2015 Red Hat, Inc.
+ * All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the
+ * next paragraph) shall be included in all copies or substantial
+ * portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#include <linux/pci.h>
+
+#include "virtgpu_drv.h"
+
+int drm_virtio_set_busid(struct drm_device *dev, struct drm_master *master)
+{
+	struct pci_dev *pdev = dev->pdev;
+
+	if (pdev) {
+		return drm_pci_set_busid(dev, master);
+	}
+	return 0;
+}
+
+int drm_virtio_init(struct drm_driver *driver, struct virtio_device *vdev)
+{
+	struct drm_device *dev;
+	int ret;
+
+	dev = drm_dev_alloc(driver, &vdev->dev);
+	if (!dev)
+		return -ENOMEM;
+	dev->virtdev = vdev;
+	vdev->priv = dev;
+
+	if (strcmp(vdev->dev.parent->bus->name, "pci") == 0) {
+		struct pci_dev *pdev = to_pci_dev(vdev->dev.parent);
+		bool vga = (pdev->class >> 8) == PCI_CLASS_DISPLAY_VGA;
+
+		if (vga) {
+			/*
+			 * Need to make sure we don't have two drivers
+			 * for the same hardware here.  Some day we
+			 * will simply kick out the firmware
+			 * (vesa/efi) framebuffer.
+			 *
+			 * Virtual hardware specs for virtio-vga are
+			 * not finalized yet, therefore we can't add
+			 * code for that yet.
+			 *
+			 * So ignore the device for the time being,
+			 * and suggest to the user use the device
+			 * variant without vga compatibility mode.
+			 */
+			DRM_ERROR("virtio-vga not (yet) supported\n");
+			DRM_ERROR("please use virtio-gpu-pci instead\n");
+			ret = -ENODEV;
+			goto err_free;
+		}
+		dev->pdev = pdev;
+	}
+
+	ret = drm_dev_register(dev, 0);
+	if (ret)
+		goto err_free;
+
+	DRM_INFO("Initialized %s %d.%d.%d %s on minor %d\n", driver->name,
+		 driver->major, driver->minor, driver->patchlevel,
+		 driver->date, dev->primary->index);
+
+	return 0;
+
+err_free:
+	drm_dev_unref(dev);
+	return ret;
+}