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, 473 insertions, 0 deletions

diff --git a/drivers/gpu/drm/virtio/virtgpu_display.c b/drivers/gpu/drm/virtio/virtgpu_display.c
new file mode 100644
index 000000000000..4e160efc9402
--- /dev/null
+++ b/drivers/gpu/drm/virtio/virtgpu_display.c
@@ -0,0 +1,473 @@
+/*
+ * Copyright (C) 2015 Red Hat, Inc.
+ * All Rights Reserved.
+ *
+ * Authors:
+ *    Dave Airlie
+ *    Alon Levy
+ *
+ * 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 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 HOLDER(S) OR AUTHOR(S) 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 "virtgpu_drv.h"
+#include <drm/drm_crtc_helper.h>
+#include <drm/drm_atomic_helper.h>
+
+#define XRES_MIN   320
+#define YRES_MIN   200
+
+#define XRES_DEF  1024
+#define YRES_DEF   768
+
+#define XRES_MAX  8192
+#define YRES_MAX  8192
+
+static void virtio_gpu_crtc_gamma_set(struct drm_crtc *crtc,
+				      u16 *red, u16 *green, u16 *blue,
+				      uint32_t start, uint32_t size)
+{
+	/* TODO */
+}
+
+static void
+virtio_gpu_hide_cursor(struct virtio_gpu_device *vgdev,
+		       struct virtio_gpu_output *output)
+{
+	output->cursor.hdr.type = cpu_to_le32(VIRTIO_GPU_CMD_UPDATE_CURSOR);
+	output->cursor.resource_id = 0;
+	virtio_gpu_cursor_ping(vgdev, output);
+}
+
+static int virtio_gpu_crtc_cursor_set(struct drm_crtc *crtc,
+				      struct drm_file *file_priv,
+				      uint32_t handle,
+				      uint32_t width,
+				      uint32_t height,
+				      int32_t hot_x, int32_t hot_y)
+{
+	struct virtio_gpu_device *vgdev = crtc->dev->dev_private;
+	struct virtio_gpu_output *output =
+		container_of(crtc, struct virtio_gpu_output, crtc);
+	struct drm_gem_object *gobj = NULL;
+	struct virtio_gpu_object *qobj = NULL;
+	struct virtio_gpu_fence *fence = NULL;
+	int ret = 0;
+
+	if (handle == 0) {
+		virtio_gpu_hide_cursor(vgdev, output);
+		return 0;
+	}
+
+	/* lookup the cursor */
+	gobj = drm_gem_object_lookup(crtc->dev, file_priv, handle);
+	if (gobj == NULL)
+		return -ENOENT;
+
+	qobj = gem_to_virtio_gpu_obj(gobj);
+
+	if (!qobj->hw_res_handle) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	virtio_gpu_cmd_transfer_to_host_2d(vgdev, qobj->hw_res_handle, 0,
+					   cpu_to_le32(64),
+					   cpu_to_le32(64),
+					   0, 0, &fence);
+
+	output->cursor.hdr.type = cpu_to_le32(VIRTIO_GPU_CMD_UPDATE_CURSOR);
+	output->cursor.resource_id = cpu_to_le32(qobj->hw_res_handle);
+	output->cursor.hot_x = cpu_to_le32(hot_x);
+	output->cursor.hot_y = cpu_to_le32(hot_y);
+	virtio_gpu_cursor_ping(vgdev, output);
+	ret = 0;
+
+out:
+	drm_gem_object_unreference_unlocked(gobj);
+	return ret;
+}
+
+static int virtio_gpu_crtc_cursor_move(struct drm_crtc *crtc,
+				    int x, int y)
+{
+	struct virtio_gpu_device *vgdev = crtc->dev->dev_private;
+	struct virtio_gpu_output *output =
+		container_of(crtc, struct virtio_gpu_output, crtc);
+
+	output->cursor.hdr.type = cpu_to_le32(VIRTIO_GPU_CMD_MOVE_CURSOR);
+	output->cursor.pos.x = cpu_to_le32(x);
+	output->cursor.pos.y = cpu_to_le32(y);
+	virtio_gpu_cursor_ping(vgdev, output);
+	return 0;
+}
+
+static const struct drm_crtc_funcs virtio_gpu_crtc_funcs = {
+	.cursor_set2            = virtio_gpu_crtc_cursor_set,
+	.cursor_move            = virtio_gpu_crtc_cursor_move,
+	.gamma_set              = virtio_gpu_crtc_gamma_set,
+	.set_config             = drm_atomic_helper_set_config,
+	.destroy                = drm_crtc_cleanup,
+
+#if 0 /* not (yet) working without vblank support according to docs */
+	.page_flip              = drm_atomic_helper_page_flip,
+#endif
+	.reset                  = drm_atomic_helper_crtc_reset,
+	.atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
+	.atomic_destroy_state   = drm_atomic_helper_crtc_destroy_state,
+};
+
+static void virtio_gpu_user_framebuffer_destroy(struct drm_framebuffer *fb)
+{
+	struct virtio_gpu_framebuffer *virtio_gpu_fb
+		= to_virtio_gpu_framebuffer(fb);
+
+	if (virtio_gpu_fb->obj)
+		drm_gem_object_unreference_unlocked(virtio_gpu_fb->obj);
+	drm_framebuffer_cleanup(fb);
+	kfree(virtio_gpu_fb);
+}
+
+static int
+virtio_gpu_framebuffer_surface_dirty(struct drm_framebuffer *fb,
+				     struct drm_file *file_priv,
+				     unsigned flags, unsigned color,
+				     struct drm_clip_rect *clips,
+				     unsigned num_clips)
+{
+	struct virtio_gpu_framebuffer *virtio_gpu_fb
+		= to_virtio_gpu_framebuffer(fb);
+
+	return virtio_gpu_surface_dirty(virtio_gpu_fb, clips, num_clips);
+}
+
+static const struct drm_framebuffer_funcs virtio_gpu_fb_funcs = {
+	.destroy = virtio_gpu_user_framebuffer_destroy,
+	.dirty = virtio_gpu_framebuffer_surface_dirty,
+};
+
+int
+virtio_gpu_framebuffer_init(struct drm_device *dev,
+			    struct virtio_gpu_framebuffer *vgfb,
+			    struct drm_mode_fb_cmd2 *mode_cmd,
+			    struct drm_gem_object *obj)
+{
+	int ret;
+	struct virtio_gpu_object *bo;
+	vgfb->obj = obj;
+
+	bo = gem_to_virtio_gpu_obj(obj);
+
+	ret = drm_framebuffer_init(dev, &vgfb->base, &virtio_gpu_fb_funcs);
+	if (ret) {
+		vgfb->obj = NULL;
+		return ret;
+	}
+	drm_helper_mode_fill_fb_struct(&vgfb->base, mode_cmd);
+
+	spin_lock_init(&vgfb->dirty_lock);
+	vgfb->x1 = vgfb->y1 = INT_MAX;
+	vgfb->x2 = vgfb->y2 = 0;
+	return 0;
+}
+
+static bool virtio_gpu_crtc_mode_fixup(struct drm_crtc *crtc,
+				       const struct drm_display_mode *mode,
+				       struct drm_display_mode *adjusted_mode)
+{
+	return true;
+}
+
+static void virtio_gpu_crtc_mode_set_nofb(struct drm_crtc *crtc)
+{
+	struct drm_device *dev = crtc->dev;
+	struct virtio_gpu_device *vgdev = dev->dev_private;
+	struct virtio_gpu_output *output = drm_crtc_to_virtio_gpu_output(crtc);
+
+	virtio_gpu_cmd_set_scanout(vgdev, output->index, 0,
+				   crtc->mode.hdisplay,
+				   crtc->mode.vdisplay, 0, 0);
+}
+
+static void virtio_gpu_crtc_enable(struct drm_crtc *crtc)
+{
+}
+
+static void virtio_gpu_crtc_disable(struct drm_crtc *crtc)
+{
+	struct drm_device *dev = crtc->dev;
+	struct virtio_gpu_device *vgdev = dev->dev_private;
+	struct virtio_gpu_output *output = drm_crtc_to_virtio_gpu_output(crtc);
+
+	virtio_gpu_cmd_set_scanout(vgdev, output->index, 0, 0, 0, 0, 0);
+}
+
+static int virtio_gpu_crtc_atomic_check(struct drm_crtc *crtc,
+					struct drm_crtc_state *state)
+{
+	return 0;
+}
+
+static const struct drm_crtc_helper_funcs virtio_gpu_crtc_helper_funcs = {
+	.enable        = virtio_gpu_crtc_enable,
+	.disable       = virtio_gpu_crtc_disable,
+	.mode_fixup    = virtio_gpu_crtc_mode_fixup,
+	.mode_set_nofb = virtio_gpu_crtc_mode_set_nofb,
+	.atomic_check  = virtio_gpu_crtc_atomic_check,
+};
+
+static bool virtio_gpu_enc_mode_fixup(struct drm_encoder *encoder,
+				      const struct drm_display_mode *mode,
+				      struct drm_display_mode *adjusted_mode)
+{
+	return true;
+}
+
+static void virtio_gpu_enc_mode_set(struct drm_encoder *encoder,
+				    struct drm_display_mode *mode,
+				    struct drm_display_mode *adjusted_mode)
+{
+}
+
+static void virtio_gpu_enc_enable(struct drm_encoder *encoder)
+{
+}
+
+static void virtio_gpu_enc_disable(struct drm_encoder *encoder)
+{
+}
+
+static int virtio_gpu_conn_get_modes(struct drm_connector *connector)
+{
+	struct virtio_gpu_output *output =
+		drm_connector_to_virtio_gpu_output(connector);
+	struct drm_display_mode *mode = NULL;
+	int count, width, height;
+
+	width  = le32_to_cpu(output->info.r.width);
+	height = le32_to_cpu(output->info.r.height);
+	count = drm_add_modes_noedid(connector, XRES_MAX, YRES_MAX);
+
+	if (width == 0 || height == 0) {
+		width = XRES_DEF;
+		height = YRES_DEF;
+		drm_set_preferred_mode(connector, XRES_DEF, YRES_DEF);
+	} else {
+		DRM_DEBUG("add mode: %dx%d\n", width, height);
+		mode = drm_cvt_mode(connector->dev, width, height, 60,
+				    false, false, false);
+		mode->type |= DRM_MODE_TYPE_PREFERRED;
+		drm_mode_probed_add(connector, mode);
+		count++;
+	}
+
+	return count;
+}
+
+static int virtio_gpu_conn_mode_valid(struct drm_connector *connector,
+				      struct drm_display_mode *mode)
+{
+	struct virtio_gpu_output *output =
+		drm_connector_to_virtio_gpu_output(connector);
+	int width, height;
+
+	width  = le32_to_cpu(output->info.r.width);
+	height = le32_to_cpu(output->info.r.height);
+
+	if (!(mode->type & DRM_MODE_TYPE_PREFERRED))
+		return MODE_OK;
+	if (mode->hdisplay == XRES_DEF && mode->vdisplay == YRES_DEF)
+		return MODE_OK;
+	if (mode->hdisplay <= width  && mode->hdisplay >= width - 16 &&
+	    mode->vdisplay <= height && mode->vdisplay >= height - 16)
+		return MODE_OK;
+
+	DRM_DEBUG("del mode: %dx%d\n", mode->hdisplay, mode->vdisplay);
+	return MODE_BAD;
+}
+
+static struct drm_encoder*
+virtio_gpu_best_encoder(struct drm_connector *connector)
+{
+	struct virtio_gpu_output *virtio_gpu_output =
+		drm_connector_to_virtio_gpu_output(connector);
+
+	return &virtio_gpu_output->enc;
+}
+
+static const struct drm_encoder_helper_funcs virtio_gpu_enc_helper_funcs = {
+	.mode_fixup = virtio_gpu_enc_mode_fixup,
+	.mode_set   = virtio_gpu_enc_mode_set,
+	.enable     = virtio_gpu_enc_enable,
+	.disable    = virtio_gpu_enc_disable,
+};
+
+static const struct drm_connector_helper_funcs virtio_gpu_conn_helper_funcs = {
+	.get_modes    = virtio_gpu_conn_get_modes,
+	.mode_valid   = virtio_gpu_conn_mode_valid,
+	.best_encoder = virtio_gpu_best_encoder,
+};
+
+static void virtio_gpu_conn_save(struct drm_connector *connector)
+{
+	DRM_DEBUG("\n");
+}
+
+static void virtio_gpu_conn_restore(struct drm_connector *connector)
+{
+	DRM_DEBUG("\n");
+}
+
+static enum drm_connector_status virtio_gpu_conn_detect(
+			struct drm_connector *connector,
+			bool force)
+{
+	struct virtio_gpu_output *output =
+		drm_connector_to_virtio_gpu_output(connector);
+
+	if (output->info.enabled)
+		return connector_status_connected;
+	else
+		return connector_status_disconnected;
+}
+
+static void virtio_gpu_conn_destroy(struct drm_connector *connector)
+{
+	struct virtio_gpu_output *virtio_gpu_output =
+		drm_connector_to_virtio_gpu_output(connector);
+
+	drm_connector_unregister(connector);
+	drm_connector_cleanup(connector);
+	kfree(virtio_gpu_output);
+}
+
+static const struct drm_connector_funcs virtio_gpu_connector_funcs = {
+	.dpms = drm_atomic_helper_connector_dpms,
+	.save = virtio_gpu_conn_save,
+	.restore = virtio_gpu_conn_restore,
+	.detect = virtio_gpu_conn_detect,
+	.fill_modes = drm_helper_probe_single_connector_modes,
+	.destroy = virtio_gpu_conn_destroy,
+	.reset = drm_atomic_helper_connector_reset,
+	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
+	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
+};
+
+static const struct drm_encoder_funcs virtio_gpu_enc_funcs = {
+	.destroy = drm_encoder_cleanup,
+};
+
+static int vgdev_output_init(struct virtio_gpu_device *vgdev, int index)
+{
+	struct drm_device *dev = vgdev->ddev;
+	struct virtio_gpu_output *output = vgdev->outputs + index;
+	struct drm_connector *connector = &output->conn;
+	struct drm_encoder *encoder = &output->enc;
+	struct drm_crtc *crtc = &output->crtc;
+	struct drm_plane *plane;
+
+	output->index = index;
+	if (index == 0) {
+		output->info.enabled = cpu_to_le32(true);
+		output->info.r.width = cpu_to_le32(XRES_DEF);
+		output->info.r.height = cpu_to_le32(YRES_DEF);
+	}
+
+	plane = virtio_gpu_plane_init(vgdev, index);
+	if (IS_ERR(plane))
+		return PTR_ERR(plane);
+	drm_crtc_init_with_planes(dev, crtc, plane, NULL,
+				  &virtio_gpu_crtc_funcs);
+	drm_mode_crtc_set_gamma_size(crtc, 256);
+	drm_crtc_helper_add(crtc, &virtio_gpu_crtc_helper_funcs);
+	plane->crtc = crtc;
+
+	drm_connector_init(dev, connector, &virtio_gpu_connector_funcs,
+			   DRM_MODE_CONNECTOR_VIRTUAL);
+	drm_connector_helper_add(connector, &virtio_gpu_conn_helper_funcs);
+
+	drm_encoder_init(dev, encoder, &virtio_gpu_enc_funcs,
+			 DRM_MODE_ENCODER_VIRTUAL);
+	drm_encoder_helper_add(encoder, &virtio_gpu_enc_helper_funcs);
+	encoder->possible_crtcs = 1 << index;
+
+	drm_mode_connector_attach_encoder(connector, encoder);
+	drm_connector_register(connector);
+	return 0;
+}
+
+static struct drm_framebuffer *
+virtio_gpu_user_framebuffer_create(struct drm_device *dev,
+				   struct drm_file *file_priv,
+				   struct drm_mode_fb_cmd2 *mode_cmd)
+{
+	struct drm_gem_object *obj = NULL;
+	struct virtio_gpu_framebuffer *virtio_gpu_fb;
+	int ret;
+
+	/* lookup object associated with res handle */
+	obj = drm_gem_object_lookup(dev, file_priv, mode_cmd->handles[0]);
+	if (!obj)
+		return ERR_PTR(-EINVAL);
+
+	virtio_gpu_fb = kzalloc(sizeof(*virtio_gpu_fb), GFP_KERNEL);
+	if (virtio_gpu_fb == NULL)
+		return ERR_PTR(-ENOMEM);
+
+	ret = virtio_gpu_framebuffer_init(dev, virtio_gpu_fb, mode_cmd, obj);
+	if (ret) {
+		kfree(virtio_gpu_fb);
+		if (obj)
+			drm_gem_object_unreference_unlocked(obj);
+		return NULL;
+	}
+
+	return &virtio_gpu_fb->base;
+}
+
+static const struct drm_mode_config_funcs virtio_gpu_mode_funcs = {
+	.fb_create = virtio_gpu_user_framebuffer_create,
+	.atomic_check = drm_atomic_helper_check,
+	.atomic_commit = drm_atomic_helper_commit,
+};
+
+int virtio_gpu_modeset_init(struct virtio_gpu_device *vgdev)
+{
+	int i;
+
+	drm_mode_config_init(vgdev->ddev);
+	vgdev->ddev->mode_config.funcs = (void *)&virtio_gpu_mode_funcs;
+
+	/* modes will be validated against the framebuffer size */
+	vgdev->ddev->mode_config.min_width = XRES_MIN;
+	vgdev->ddev->mode_config.min_height = YRES_MIN;
+	vgdev->ddev->mode_config.max_width = XRES_MAX;
+	vgdev->ddev->mode_config.max_height = YRES_MAX;
+
+	for (i = 0 ; i < vgdev->num_scanouts; ++i)
+		vgdev_output_init(vgdev, i);
+
+        drm_mode_config_reset(vgdev->ddev);
+	return 0;
+}
+
+void virtio_gpu_modeset_fini(struct virtio_gpu_device *vgdev)
+{
+	virtio_gpu_fbdev_fini(vgdev);
+	drm_mode_config_cleanup(vgdev->ddev);
+}