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 #include <drm/drmP.h>
29 #include "virtgpu_drv.h"
30 
31 static int virtio_gpu_fbdev = 1;
32 
33 MODULE_PARM_DESC(fbdev, "Disable/Enable framebuffer device & console");
34 module_param_named(fbdev, virtio_gpu_fbdev, int, 0400);
35 
36 static void virtio_gpu_config_changed_work_func(struct work_struct *work)
37 {
38 	struct virtio_gpu_device *vgdev =
39 		container_of(work, struct virtio_gpu_device,
40 			     config_changed_work);
41 	u32 events_read, events_clear = 0;
42 
43 	/* read the config space */
44 	virtio_cread(vgdev->vdev, struct virtio_gpu_config,
45 		     events_read, &events_read);
46 	if (events_read & VIRTIO_GPU_EVENT_DISPLAY) {
47 		virtio_gpu_cmd_get_display_info(vgdev);
48 		drm_helper_hpd_irq_event(vgdev->ddev);
49 		events_clear |= VIRTIO_GPU_EVENT_DISPLAY;
50 	}
51 	virtio_cwrite(vgdev->vdev, struct virtio_gpu_config,
52 		      events_clear, &events_clear);
53 }
54 
55 static int virtio_gpu_context_create(struct virtio_gpu_device *vgdev,
56 				      uint32_t nlen, const char *name)
57 {
58 	int handle = ida_alloc(&vgdev->ctx_id_ida, GFP_KERNEL);
59 
60 	if (handle < 0)
61 		return handle;
62 	handle += 1;
63 	virtio_gpu_cmd_context_create(vgdev, handle, nlen, name);
64 	return handle;
65 }
66 
67 static void virtio_gpu_context_destroy(struct virtio_gpu_device *vgdev,
68 				      uint32_t ctx_id)
69 {
70 	virtio_gpu_cmd_context_destroy(vgdev, ctx_id);
71 	ida_free(&vgdev->ctx_id_ida, ctx_id - 1);
72 }
73 
74 static void virtio_gpu_init_vq(struct virtio_gpu_queue *vgvq,
75 			       void (*work_func)(struct work_struct *work))
76 {
77 	spin_lock_init(&vgvq->qlock);
78 	init_waitqueue_head(&vgvq->ack_queue);
79 	INIT_WORK(&vgvq->dequeue_work, work_func);
80 }
81 
82 static void virtio_gpu_get_capsets(struct virtio_gpu_device *vgdev,
83 				   int num_capsets)
84 {
85 	int i, ret;
86 
87 	vgdev->capsets = kcalloc(num_capsets,
88 				 sizeof(struct virtio_gpu_drv_capset),
89 				 GFP_KERNEL);
90 	if (!vgdev->capsets) {
91 		DRM_ERROR("failed to allocate cap sets\n");
92 		return;
93 	}
94 	for (i = 0; i < num_capsets; i++) {
95 		virtio_gpu_cmd_get_capset_info(vgdev, i);
96 		ret = wait_event_timeout(vgdev->resp_wq,
97 					 vgdev->capsets[i].id > 0, 5 * HZ);
98 		if (ret == 0) {
99 			DRM_ERROR("timed out waiting for cap set %d\n", i);
100 			kfree(vgdev->capsets);
101 			vgdev->capsets = NULL;
102 			return;
103 		}
104 		DRM_INFO("cap set %d: id %d, max-version %d, max-size %d\n",
105 			 i, vgdev->capsets[i].id,
106 			 vgdev->capsets[i].max_version,
107 			 vgdev->capsets[i].max_size);
108 	}
109 	vgdev->num_capsets = num_capsets;
110 }
111 
112 int virtio_gpu_driver_load(struct drm_device *dev, unsigned long flags)
113 {
114 	static vq_callback_t *callbacks[] = {
115 		virtio_gpu_ctrl_ack, virtio_gpu_cursor_ack
116 	};
117 	static const char * const names[] = { "control", "cursor" };
118 
119 	struct virtio_gpu_device *vgdev;
120 	/* this will expand later */
121 	struct virtqueue *vqs[2];
122 	u32 num_scanouts, num_capsets;
123 	int ret;
124 
125 	if (!virtio_has_feature(dev_to_virtio(dev->dev), VIRTIO_F_VERSION_1))
126 		return -ENODEV;
127 
128 	vgdev = kzalloc(sizeof(struct virtio_gpu_device), GFP_KERNEL);
129 	if (!vgdev)
130 		return -ENOMEM;
131 
132 	vgdev->ddev = dev;
133 	dev->dev_private = vgdev;
134 	vgdev->vdev = dev_to_virtio(dev->dev);
135 	vgdev->dev = dev->dev;
136 
137 	spin_lock_init(&vgdev->display_info_lock);
138 	ida_init(&vgdev->ctx_id_ida);
139 	ida_init(&vgdev->resource_ida);
140 	init_waitqueue_head(&vgdev->resp_wq);
141 	virtio_gpu_init_vq(&vgdev->ctrlq, virtio_gpu_dequeue_ctrl_func);
142 	virtio_gpu_init_vq(&vgdev->cursorq, virtio_gpu_dequeue_cursor_func);
143 
144 	vgdev->fence_drv.context = dma_fence_context_alloc(1);
145 	spin_lock_init(&vgdev->fence_drv.lock);
146 	INIT_LIST_HEAD(&vgdev->fence_drv.fences);
147 	INIT_LIST_HEAD(&vgdev->cap_cache);
148 	INIT_WORK(&vgdev->config_changed_work,
149 		  virtio_gpu_config_changed_work_func);
150 
151 #ifdef __LITTLE_ENDIAN
152 	if (virtio_has_feature(vgdev->vdev, VIRTIO_GPU_F_VIRGL))
153 		vgdev->has_virgl_3d = true;
154 	DRM_INFO("virgl 3d acceleration %s\n",
155 		 vgdev->has_virgl_3d ? "enabled" : "not supported by host");
156 #else
157 	DRM_INFO("virgl 3d acceleration not supported by guest\n");
158 #endif
159 
160 	ret = virtio_find_vqs(vgdev->vdev, 2, vqs, callbacks, names, NULL);
161 	if (ret) {
162 		DRM_ERROR("failed to find virt queues\n");
163 		goto err_vqs;
164 	}
165 	vgdev->ctrlq.vq = vqs[0];
166 	vgdev->cursorq.vq = vqs[1];
167 	ret = virtio_gpu_alloc_vbufs(vgdev);
168 	if (ret) {
169 		DRM_ERROR("failed to alloc vbufs\n");
170 		goto err_vbufs;
171 	}
172 
173 	ret = virtio_gpu_ttm_init(vgdev);
174 	if (ret) {
175 		DRM_ERROR("failed to init ttm %d\n", ret);
176 		goto err_ttm;
177 	}
178 
179 	/* get display info */
180 	virtio_cread(vgdev->vdev, struct virtio_gpu_config,
181 		     num_scanouts, &num_scanouts);
182 	vgdev->num_scanouts = min_t(uint32_t, num_scanouts,
183 				    VIRTIO_GPU_MAX_SCANOUTS);
184 	if (!vgdev->num_scanouts) {
185 		DRM_ERROR("num_scanouts is zero\n");
186 		ret = -EINVAL;
187 		goto err_scanouts;
188 	}
189 	DRM_INFO("number of scanouts: %d\n", num_scanouts);
190 
191 	virtio_cread(vgdev->vdev, struct virtio_gpu_config,
192 		     num_capsets, &num_capsets);
193 	DRM_INFO("number of cap sets: %d\n", num_capsets);
194 
195 	ret = virtio_gpu_modeset_init(vgdev);
196 	if (ret)
197 		goto err_modeset;
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 	virtio_gpu_cmd_get_display_info(vgdev);
205 	wait_event_timeout(vgdev->resp_wq, !vgdev->display_info_pending,
206 			   5 * HZ);
207 	if (virtio_gpu_fbdev)
208 		virtio_gpu_fbdev_init(vgdev);
209 
210 	return 0;
211 
212 err_modeset:
213 err_scanouts:
214 	virtio_gpu_ttm_fini(vgdev);
215 err_ttm:
216 	virtio_gpu_free_vbufs(vgdev);
217 err_vbufs:
218 	vgdev->vdev->config->del_vqs(vgdev->vdev);
219 err_vqs:
220 	kfree(vgdev);
221 	return ret;
222 }
223 
224 static void virtio_gpu_cleanup_cap_cache(struct virtio_gpu_device *vgdev)
225 {
226 	struct virtio_gpu_drv_cap_cache *cache_ent, *tmp;
227 
228 	list_for_each_entry_safe(cache_ent, tmp, &vgdev->cap_cache, head) {
229 		kfree(cache_ent->caps_cache);
230 		kfree(cache_ent);
231 	}
232 }
233 
234 void virtio_gpu_driver_unload(struct drm_device *dev)
235 {
236 	struct virtio_gpu_device *vgdev = dev->dev_private;
237 
238 	vgdev->vqs_ready = false;
239 	flush_work(&vgdev->ctrlq.dequeue_work);
240 	flush_work(&vgdev->cursorq.dequeue_work);
241 	flush_work(&vgdev->config_changed_work);
242 	vgdev->vdev->config->del_vqs(vgdev->vdev);
243 
244 	virtio_gpu_modeset_fini(vgdev);
245 	virtio_gpu_ttm_fini(vgdev);
246 	virtio_gpu_free_vbufs(vgdev);
247 	virtio_gpu_cleanup_cap_cache(vgdev);
248 	kfree(vgdev->capsets);
249 	kfree(vgdev);
250 }
251 
252 int virtio_gpu_driver_open(struct drm_device *dev, struct drm_file *file)
253 {
254 	struct virtio_gpu_device *vgdev = dev->dev_private;
255 	struct virtio_gpu_fpriv *vfpriv;
256 	int id;
257 	char dbgname[TASK_COMM_LEN];
258 
259 	/* can't create contexts without 3d renderer */
260 	if (!vgdev->has_virgl_3d)
261 		return 0;
262 
263 	/* allocate a virt GPU context for this opener */
264 	vfpriv = kzalloc(sizeof(*vfpriv), GFP_KERNEL);
265 	if (!vfpriv)
266 		return -ENOMEM;
267 
268 	get_task_comm(dbgname, current);
269 	id = virtio_gpu_context_create(vgdev, strlen(dbgname), dbgname);
270 	if (id < 0) {
271 		kfree(vfpriv);
272 		return id;
273 	}
274 
275 	vfpriv->ctx_id = id;
276 	file->driver_priv = vfpriv;
277 	return 0;
278 }
279 
280 void virtio_gpu_driver_postclose(struct drm_device *dev, struct drm_file *file)
281 {
282 	struct virtio_gpu_device *vgdev = dev->dev_private;
283 	struct virtio_gpu_fpriv *vfpriv;
284 
285 	if (!vgdev->has_virgl_3d)
286 		return;
287 
288 	vfpriv = file->driver_priv;
289 
290 	virtio_gpu_context_destroy(vgdev, vfpriv->ctx_id);
291 	kfree(vfpriv);
292 	file->driver_priv = NULL;
293 }
294