1 /*
2  * Copyright (C) 2015 Red Hat, Inc.
3  * All Rights Reserved.
4  *
5  * Permission is hereby granted, free of charge, to any person obtaining
6  * a copy of this software and associated documentation files (the
7  * "Software"), to deal in the Software without restriction, including
8  * without limitation the rights to use, copy, modify, merge, publish,
9  * distribute, sublicense, and/or sell copies of the Software, and to
10  * permit persons to whom the Software is furnished to do so, subject to
11  * the following conditions:
12  *
13  * The above copyright notice and this permission notice (including the
14  * next paragraph) shall be included in all copies or substantial
15  * portions of the Software.
16  *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
18  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
19  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
20  * IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
21  * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
22  * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
23  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
24  */
25 
26 #include <linux/virtio.h>
27 #include <linux/virtio_config.h>
28 
29 #include <drm/drm_file.h>
30 
31 #include "virtgpu_drv.h"
32 
33 static void virtio_gpu_config_changed_work_func(struct work_struct *work)
34 {
35 	struct virtio_gpu_device *vgdev =
36 		container_of(work, struct virtio_gpu_device,
37 			     config_changed_work);
38 	u32 events_read, events_clear = 0;
39 
40 	/* read the config space */
41 	virtio_cread(vgdev->vdev, struct virtio_gpu_config,
42 		     events_read, &events_read);
43 	if (events_read & VIRTIO_GPU_EVENT_DISPLAY) {
44 		if (vgdev->has_edid)
45 			virtio_gpu_cmd_get_edids(vgdev);
46 		virtio_gpu_cmd_get_display_info(vgdev);
47 		drm_helper_hpd_irq_event(vgdev->ddev);
48 		events_clear |= VIRTIO_GPU_EVENT_DISPLAY;
49 	}
50 	virtio_cwrite(vgdev->vdev, struct virtio_gpu_config,
51 		      events_clear, &events_clear);
52 }
53 
54 static int virtio_gpu_context_create(struct virtio_gpu_device *vgdev,
55 				      uint32_t nlen, const char *name)
56 {
57 	int handle = ida_alloc(&vgdev->ctx_id_ida, GFP_KERNEL);
58 
59 	if (handle < 0)
60 		return handle;
61 	handle += 1;
62 	virtio_gpu_cmd_context_create(vgdev, handle, nlen, name);
63 	return handle;
64 }
65 
66 static void virtio_gpu_context_destroy(struct virtio_gpu_device *vgdev,
67 				      uint32_t ctx_id)
68 {
69 	virtio_gpu_cmd_context_destroy(vgdev, ctx_id);
70 	ida_free(&vgdev->ctx_id_ida, ctx_id - 1);
71 }
72 
73 static void virtio_gpu_init_vq(struct virtio_gpu_queue *vgvq,
74 			       void (*work_func)(struct work_struct *work))
75 {
76 	spin_lock_init(&vgvq->qlock);
77 	init_waitqueue_head(&vgvq->ack_queue);
78 	INIT_WORK(&vgvq->dequeue_work, work_func);
79 }
80 
81 static void virtio_gpu_get_capsets(struct virtio_gpu_device *vgdev,
82 				   int num_capsets)
83 {
84 	int i, ret;
85 
86 	vgdev->capsets = kcalloc(num_capsets,
87 				 sizeof(struct virtio_gpu_drv_capset),
88 				 GFP_KERNEL);
89 	if (!vgdev->capsets) {
90 		DRM_ERROR("failed to allocate cap sets\n");
91 		return;
92 	}
93 	for (i = 0; i < num_capsets; i++) {
94 		virtio_gpu_cmd_get_capset_info(vgdev, i);
95 		ret = wait_event_timeout(vgdev->resp_wq,
96 					 vgdev->capsets[i].id > 0, 5 * HZ);
97 		if (ret == 0) {
98 			DRM_ERROR("timed out waiting for cap set %d\n", i);
99 			kfree(vgdev->capsets);
100 			vgdev->capsets = NULL;
101 			return;
102 		}
103 		DRM_INFO("cap set %d: id %d, max-version %d, max-size %d\n",
104 			 i, vgdev->capsets[i].id,
105 			 vgdev->capsets[i].max_version,
106 			 vgdev->capsets[i].max_size);
107 	}
108 	vgdev->num_capsets = num_capsets;
109 }
110 
111 int virtio_gpu_init(struct drm_device *dev)
112 {
113 	static vq_callback_t *callbacks[] = {
114 		virtio_gpu_ctrl_ack, virtio_gpu_cursor_ack
115 	};
116 	static const char * const names[] = { "control", "cursor" };
117 
118 	struct virtio_gpu_device *vgdev;
119 	/* this will expand later */
120 	struct virtqueue *vqs[2];
121 	u32 num_scanouts, num_capsets;
122 	int ret;
123 
124 	if (!virtio_has_feature(dev_to_virtio(dev->dev), VIRTIO_F_VERSION_1))
125 		return -ENODEV;
126 
127 	vgdev = kzalloc(sizeof(struct virtio_gpu_device), GFP_KERNEL);
128 	if (!vgdev)
129 		return -ENOMEM;
130 
131 	vgdev->ddev = dev;
132 	dev->dev_private = vgdev;
133 	vgdev->vdev = dev_to_virtio(dev->dev);
134 	vgdev->dev = dev->dev;
135 
136 	spin_lock_init(&vgdev->display_info_lock);
137 	ida_init(&vgdev->ctx_id_ida);
138 	ida_init(&vgdev->resource_ida);
139 	init_waitqueue_head(&vgdev->resp_wq);
140 	virtio_gpu_init_vq(&vgdev->ctrlq, virtio_gpu_dequeue_ctrl_func);
141 	virtio_gpu_init_vq(&vgdev->cursorq, virtio_gpu_dequeue_cursor_func);
142 
143 	vgdev->fence_drv.context = dma_fence_context_alloc(1);
144 	spin_lock_init(&vgdev->fence_drv.lock);
145 	INIT_LIST_HEAD(&vgdev->fence_drv.fences);
146 	INIT_LIST_HEAD(&vgdev->cap_cache);
147 	INIT_WORK(&vgdev->config_changed_work,
148 		  virtio_gpu_config_changed_work_func);
149 
150 	INIT_WORK(&vgdev->obj_free_work,
151 		  virtio_gpu_array_put_free_work);
152 	INIT_LIST_HEAD(&vgdev->obj_free_list);
153 	spin_lock_init(&vgdev->obj_free_lock);
154 
155 #ifdef __LITTLE_ENDIAN
156 	if (virtio_has_feature(vgdev->vdev, VIRTIO_GPU_F_VIRGL))
157 		vgdev->has_virgl_3d = true;
158 	DRM_INFO("virgl 3d acceleration %s\n",
159 		 vgdev->has_virgl_3d ? "enabled" : "not supported by host");
160 #else
161 	DRM_INFO("virgl 3d acceleration not supported by guest\n");
162 #endif
163 	if (virtio_has_feature(vgdev->vdev, VIRTIO_GPU_F_EDID)) {
164 		vgdev->has_edid = true;
165 		DRM_INFO("EDID support available.\n");
166 	}
167 
168 	ret = virtio_find_vqs(vgdev->vdev, 2, vqs, callbacks, names, NULL);
169 	if (ret) {
170 		DRM_ERROR("failed to find virt queues\n");
171 		goto err_vqs;
172 	}
173 	vgdev->ctrlq.vq = vqs[0];
174 	vgdev->cursorq.vq = vqs[1];
175 	ret = virtio_gpu_alloc_vbufs(vgdev);
176 	if (ret) {
177 		DRM_ERROR("failed to alloc vbufs\n");
178 		goto err_vbufs;
179 	}
180 
181 	/* get display info */
182 	virtio_cread(vgdev->vdev, struct virtio_gpu_config,
183 		     num_scanouts, &num_scanouts);
184 	vgdev->num_scanouts = min_t(uint32_t, num_scanouts,
185 				    VIRTIO_GPU_MAX_SCANOUTS);
186 	if (!vgdev->num_scanouts) {
187 		DRM_ERROR("num_scanouts is zero\n");
188 		ret = -EINVAL;
189 		goto err_scanouts;
190 	}
191 	DRM_INFO("number of scanouts: %d\n", num_scanouts);
192 
193 	virtio_cread(vgdev->vdev, struct virtio_gpu_config,
194 		     num_capsets, &num_capsets);
195 	DRM_INFO("number of cap sets: %d\n", num_capsets);
196 
197 	virtio_gpu_modeset_init(vgdev);
198 
199 	virtio_device_ready(vgdev->vdev);
200 	vgdev->vqs_ready = true;
201 
202 	if (num_capsets)
203 		virtio_gpu_get_capsets(vgdev, num_capsets);
204 	if (vgdev->has_edid)
205 		virtio_gpu_cmd_get_edids(vgdev);
206 	virtio_gpu_cmd_get_display_info(vgdev);
207 	wait_event_timeout(vgdev->resp_wq, !vgdev->display_info_pending,
208 			   5 * HZ);
209 	return 0;
210 
211 err_scanouts:
212 	virtio_gpu_free_vbufs(vgdev);
213 err_vbufs:
214 	vgdev->vdev->config->del_vqs(vgdev->vdev);
215 err_vqs:
216 	kfree(vgdev);
217 	return ret;
218 }
219 
220 static void virtio_gpu_cleanup_cap_cache(struct virtio_gpu_device *vgdev)
221 {
222 	struct virtio_gpu_drv_cap_cache *cache_ent, *tmp;
223 
224 	list_for_each_entry_safe(cache_ent, tmp, &vgdev->cap_cache, head) {
225 		kfree(cache_ent->caps_cache);
226 		kfree(cache_ent);
227 	}
228 }
229 
230 void virtio_gpu_deinit(struct drm_device *dev)
231 {
232 	struct virtio_gpu_device *vgdev = dev->dev_private;
233 
234 	flush_work(&vgdev->obj_free_work);
235 	vgdev->vqs_ready = false;
236 	flush_work(&vgdev->ctrlq.dequeue_work);
237 	flush_work(&vgdev->cursorq.dequeue_work);
238 	flush_work(&vgdev->config_changed_work);
239 	vgdev->vdev->config->reset(vgdev->vdev);
240 	vgdev->vdev->config->del_vqs(vgdev->vdev);
241 
242 	virtio_gpu_modeset_fini(vgdev);
243 	virtio_gpu_free_vbufs(vgdev);
244 	virtio_gpu_cleanup_cap_cache(vgdev);
245 	kfree(vgdev->capsets);
246 	kfree(vgdev);
247 }
248 
249 int virtio_gpu_driver_open(struct drm_device *dev, struct drm_file *file)
250 {
251 	struct virtio_gpu_device *vgdev = dev->dev_private;
252 	struct virtio_gpu_fpriv *vfpriv;
253 	int id;
254 	char dbgname[TASK_COMM_LEN];
255 
256 	/* can't create contexts without 3d renderer */
257 	if (!vgdev->has_virgl_3d)
258 		return 0;
259 
260 	/* allocate a virt GPU context for this opener */
261 	vfpriv = kzalloc(sizeof(*vfpriv), GFP_KERNEL);
262 	if (!vfpriv)
263 		return -ENOMEM;
264 
265 	get_task_comm(dbgname, current);
266 	id = virtio_gpu_context_create(vgdev, strlen(dbgname), dbgname);
267 	if (id < 0) {
268 		kfree(vfpriv);
269 		return id;
270 	}
271 
272 	vfpriv->ctx_id = id;
273 	file->driver_priv = vfpriv;
274 	return 0;
275 }
276 
277 void virtio_gpu_driver_postclose(struct drm_device *dev, struct drm_file *file)
278 {
279 	struct virtio_gpu_device *vgdev = dev->dev_private;
280 	struct virtio_gpu_fpriv *vfpriv;
281 
282 	if (!vgdev->has_virgl_3d)
283 		return;
284 
285 	vfpriv = file->driver_priv;
286 
287 	virtio_gpu_context_destroy(vgdev, vfpriv->ctx_id);
288 	kfree(vfpriv);
289 	file->driver_priv = NULL;
290 }
291