1 /*
2  * Copyright (C) 2015 Red Hat, Inc.
3  * All Rights Reserved.
4  *
5  * Authors:
6  *    Dave Airlie <airlied@redhat.com>
7  *    Gerd Hoffmann <kraxel@redhat.com>
8  *
9  * Permission is hereby granted, free of charge, to any person obtaining a
10  * copy of this software and associated documentation files (the "Software"),
11  * to deal in the Software without restriction, including without limitation
12  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
13  * and/or sell copies of the Software, and to permit persons to whom the
14  * Software is furnished to do so, subject to the following conditions:
15  *
16  * The above copyright notice and this permission notice (including the next
17  * paragraph) shall be included in all copies or substantial portions of the
18  * Software.
19  *
20  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
21  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
22  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
23  * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
24  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
25  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
26  * OTHER DEALINGS IN THE SOFTWARE.
27  */
28 
29 #include <linux/module.h>
30 #include <linux/console.h>
31 #include <linux/pci.h>
32 
33 #include <drm/drm.h>
34 #include <drm/drm_drv.h>
35 #include <drm/drm_file.h>
36 
37 #include "virtgpu_drv.h"
38 
39 static struct drm_driver driver;
40 
41 static int virtio_gpu_modeset = -1;
42 
43 MODULE_PARM_DESC(modeset, "Disable/Enable modesetting");
44 module_param_named(modeset, virtio_gpu_modeset, int, 0400);
45 
46 static int virtio_gpu_pci_quirk(struct drm_device *dev, struct virtio_device *vdev)
47 {
48 	struct pci_dev *pdev = to_pci_dev(vdev->dev.parent);
49 	const char *pname = dev_name(&pdev->dev);
50 	bool vga = (pdev->class >> 8) == PCI_CLASS_DISPLAY_VGA;
51 	char unique[20];
52 
53 	DRM_INFO("pci: %s detected at %s\n",
54 		 vga ? "virtio-vga" : "virtio-gpu-pci",
55 		 pname);
56 	dev->pdev = pdev;
57 	if (vga)
58 		drm_fb_helper_remove_conflicting_pci_framebuffers(pdev,
59 								  0,
60 								  "virtiodrmfb");
61 
62 	/*
63 	 * Normally the drm_dev_set_unique() call is done by core DRM.
64 	 * The following comment covers, why virtio cannot rely on it.
65 	 *
66 	 * Unlike the other virtual GPU drivers, virtio abstracts the
67 	 * underlying bus type by using struct virtio_device.
68 	 *
69 	 * Hence the dev_is_pci() check, used in core DRM, will fail
70 	 * and the unique returned will be the virtio_device "virtio0",
71 	 * while a "pci:..." one is required.
72 	 *
73 	 * A few other ideas were considered:
74 	 * - Extend the dev_is_pci() check [in drm_set_busid] to
75 	 *   consider virtio.
76 	 *   Seems like a bigger hack than what we have already.
77 	 *
78 	 * - Point drm_device::dev to the parent of the virtio_device
79 	 *   Semantic changes:
80 	 *   * Using the wrong device for i2c, framebuffer_alloc and
81 	 *     prime import.
82 	 *   Visual changes:
83 	 *   * Helpers such as DRM_DEV_ERROR, dev_info, drm_printer,
84 	 *     will print the wrong information.
85 	 *
86 	 * We could address the latter issues, by introducing
87 	 * drm_device::bus_dev, ... which would be used solely for this.
88 	 *
89 	 * So for the moment keep things as-is, with a bulky comment
90 	 * for the next person who feels like removing this
91 	 * drm_dev_set_unique() quirk.
92 	 */
93 	snprintf(unique, sizeof(unique), "pci:%s", pname);
94 	return drm_dev_set_unique(dev, unique);
95 }
96 
97 static int virtio_gpu_probe(struct virtio_device *vdev)
98 {
99 	struct drm_device *dev;
100 	int ret;
101 
102 	if (vgacon_text_force() && virtio_gpu_modeset == -1)
103 		return -EINVAL;
104 
105 	if (virtio_gpu_modeset == 0)
106 		return -EINVAL;
107 
108 	dev = drm_dev_alloc(&driver, &vdev->dev);
109 	if (IS_ERR(dev))
110 		return PTR_ERR(dev);
111 	vdev->priv = dev;
112 
113 	if (!strcmp(vdev->dev.parent->bus->name, "pci")) {
114 		ret = virtio_gpu_pci_quirk(dev, vdev);
115 		if (ret)
116 			goto err_free;
117 	}
118 
119 	ret = virtio_gpu_init(dev);
120 	if (ret)
121 		goto err_free;
122 
123 	ret = drm_dev_register(dev, 0);
124 	if (ret)
125 		goto err_free;
126 
127 	drm_fbdev_generic_setup(vdev->priv, 32);
128 	return 0;
129 
130 err_free:
131 	drm_dev_put(dev);
132 	return ret;
133 }
134 
135 static void virtio_gpu_remove(struct virtio_device *vdev)
136 {
137 	struct drm_device *dev = vdev->priv;
138 
139 	drm_dev_unregister(dev);
140 	virtio_gpu_deinit(dev);
141 	drm_put_dev(dev);
142 }
143 
144 static void virtio_gpu_config_changed(struct virtio_device *vdev)
145 {
146 	struct drm_device *dev = vdev->priv;
147 	struct virtio_gpu_device *vgdev = dev->dev_private;
148 
149 	schedule_work(&vgdev->config_changed_work);
150 }
151 
152 static struct virtio_device_id id_table[] = {
153 	{ VIRTIO_ID_GPU, VIRTIO_DEV_ANY_ID },
154 	{ 0 },
155 };
156 
157 static unsigned int features[] = {
158 #ifdef __LITTLE_ENDIAN
159 	/*
160 	 * Gallium command stream send by virgl is native endian.
161 	 * Because of that we only support little endian guests on
162 	 * little endian hosts.
163 	 */
164 	VIRTIO_GPU_F_VIRGL,
165 #endif
166 	VIRTIO_GPU_F_EDID,
167 };
168 static struct virtio_driver virtio_gpu_driver = {
169 	.feature_table = features,
170 	.feature_table_size = ARRAY_SIZE(features),
171 	.driver.name = KBUILD_MODNAME,
172 	.driver.owner = THIS_MODULE,
173 	.id_table = id_table,
174 	.probe = virtio_gpu_probe,
175 	.remove = virtio_gpu_remove,
176 	.config_changed = virtio_gpu_config_changed
177 };
178 
179 module_virtio_driver(virtio_gpu_driver);
180 
181 MODULE_DEVICE_TABLE(virtio, id_table);
182 MODULE_DESCRIPTION("Virtio GPU driver");
183 MODULE_LICENSE("GPL and additional rights");
184 MODULE_AUTHOR("Dave Airlie <airlied@redhat.com>");
185 MODULE_AUTHOR("Gerd Hoffmann <kraxel@redhat.com>");
186 MODULE_AUTHOR("Alon Levy");
187 
188 static const struct file_operations virtio_gpu_driver_fops = {
189 	.owner = THIS_MODULE,
190 	.open = drm_open,
191 	.mmap = virtio_gpu_mmap,
192 	.poll = drm_poll,
193 	.read = drm_read,
194 	.unlocked_ioctl	= drm_ioctl,
195 	.release = drm_release,
196 	.compat_ioctl = drm_compat_ioctl,
197 	.llseek = noop_llseek,
198 };
199 
200 static struct drm_driver driver = {
201 	.driver_features = DRIVER_MODESET | DRIVER_GEM | DRIVER_RENDER | DRIVER_ATOMIC,
202 	.open = virtio_gpu_driver_open,
203 	.postclose = virtio_gpu_driver_postclose,
204 
205 	.dumb_create = virtio_gpu_mode_dumb_create,
206 	.dumb_map_offset = virtio_gpu_mode_dumb_mmap,
207 
208 #if defined(CONFIG_DEBUG_FS)
209 	.debugfs_init = virtio_gpu_debugfs_init,
210 #endif
211 	.prime_handle_to_fd = drm_gem_prime_handle_to_fd,
212 	.prime_fd_to_handle = drm_gem_prime_fd_to_handle,
213 	.gem_prime_get_sg_table = virtgpu_gem_prime_get_sg_table,
214 	.gem_prime_import_sg_table = virtgpu_gem_prime_import_sg_table,
215 	.gem_prime_vmap = virtgpu_gem_prime_vmap,
216 	.gem_prime_vunmap = virtgpu_gem_prime_vunmap,
217 	.gem_prime_mmap = virtgpu_gem_prime_mmap,
218 
219 	.gem_free_object_unlocked = virtio_gpu_gem_free_object,
220 	.gem_open_object = virtio_gpu_gem_object_open,
221 	.gem_close_object = virtio_gpu_gem_object_close,
222 	.fops = &virtio_gpu_driver_fops,
223 
224 	.ioctls = virtio_gpu_ioctls,
225 	.num_ioctls = DRM_VIRTIO_NUM_IOCTLS,
226 
227 	.name = DRIVER_NAME,
228 	.desc = DRIVER_DESC,
229 	.date = DRIVER_DATE,
230 	.major = DRIVER_MAJOR,
231 	.minor = DRIVER_MINOR,
232 	.patchlevel = DRIVER_PATCHLEVEL,
233 };
234