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 #include <drm/drmP.h>
33 #include <drm/drm.h>
34 
35 #include "virtgpu_drv.h"
36 static struct drm_driver driver;
37 
38 static int virtio_gpu_modeset = -1;
39 
40 MODULE_PARM_DESC(modeset, "Disable/Enable modesetting");
41 module_param_named(modeset, virtio_gpu_modeset, int, 0400);
42 
43 static int virtio_gpu_pci_quirk(struct drm_device *dev, struct virtio_device *vdev)
44 {
45 	struct pci_dev *pdev = to_pci_dev(vdev->dev.parent);
46 	const char *pname = dev_name(&pdev->dev);
47 	bool vga = (pdev->class >> 8) == PCI_CLASS_DISPLAY_VGA;
48 	char unique[20];
49 
50 	DRM_INFO("pci: %s detected at %s\n",
51 		 vga ? "virtio-vga" : "virtio-gpu-pci",
52 		 pname);
53 	dev->pdev = pdev;
54 	if (vga)
55 		drm_fb_helper_remove_conflicting_pci_framebuffers(pdev,
56 								  0,
57 								  "virtiodrmfb");
58 
59 	/*
60 	 * Normally the drm_dev_set_unique() call is done by core DRM.
61 	 * The following comment covers, why virtio cannot rely on it.
62 	 *
63 	 * Unlike the other virtual GPU drivers, virtio abstracts the
64 	 * underlying bus type by using struct virtio_device.
65 	 *
66 	 * Hence the dev_is_pci() check, used in core DRM, will fail
67 	 * and the unique returned will be the virtio_device "virtio0",
68 	 * while a "pci:..." one is required.
69 	 *
70 	 * A few other ideas were considered:
71 	 * - Extend the dev_is_pci() check [in drm_set_busid] to
72 	 *   consider virtio.
73 	 *   Seems like a bigger hack than what we have already.
74 	 *
75 	 * - Point drm_device::dev to the parent of the virtio_device
76 	 *   Semantic changes:
77 	 *   * Using the wrong device for i2c, framebuffer_alloc and
78 	 *     prime import.
79 	 *   Visual changes:
80 	 *   * Helpers such as DRM_DEV_ERROR, dev_info, drm_printer,
81 	 *     will print the wrong information.
82 	 *
83 	 * We could address the latter issues, by introducing
84 	 * drm_device::bus_dev, ... which would be used solely for this.
85 	 *
86 	 * So for the moment keep things as-is, with a bulky comment
87 	 * for the next person who feels like removing this
88 	 * drm_dev_set_unique() quirk.
89 	 */
90 	snprintf(unique, sizeof(unique), "pci:%s", pname);
91 	return drm_dev_set_unique(dev, unique);
92 }
93 
94 static int virtio_gpu_probe(struct virtio_device *vdev)
95 {
96 	struct drm_device *dev;
97 	int ret;
98 
99 	if (vgacon_text_force() && virtio_gpu_modeset == -1)
100 		return -EINVAL;
101 
102 	if (virtio_gpu_modeset == 0)
103 		return -EINVAL;
104 
105 	dev = drm_dev_alloc(&driver, &vdev->dev);
106 	if (IS_ERR(dev))
107 		return PTR_ERR(dev);
108 	vdev->priv = dev;
109 
110 	if (!strcmp(vdev->dev.parent->bus->name, "pci")) {
111 		ret = virtio_gpu_pci_quirk(dev, vdev);
112 		if (ret)
113 			goto err_free;
114 	}
115 
116 	ret = virtio_gpu_init(dev);
117 	if (ret)
118 		goto err_free;
119 
120 	ret = drm_dev_register(dev, 0);
121 	if (ret)
122 		goto err_free;
123 
124 	drm_fbdev_generic_setup(vdev->priv, 32);
125 	return 0;
126 
127 err_free:
128 	drm_dev_put(dev);
129 	return ret;
130 }
131 
132 static void virtio_gpu_remove(struct virtio_device *vdev)
133 {
134 	struct drm_device *dev = vdev->priv;
135 
136 	drm_dev_unregister(dev);
137 	virtio_gpu_deinit(dev);
138 	drm_put_dev(dev);
139 }
140 
141 static void virtio_gpu_config_changed(struct virtio_device *vdev)
142 {
143 	struct drm_device *dev = vdev->priv;
144 	struct virtio_gpu_device *vgdev = dev->dev_private;
145 
146 	schedule_work(&vgdev->config_changed_work);
147 }
148 
149 static struct virtio_device_id id_table[] = {
150 	{ VIRTIO_ID_GPU, VIRTIO_DEV_ANY_ID },
151 	{ 0 },
152 };
153 
154 static unsigned int features[] = {
155 #ifdef __LITTLE_ENDIAN
156 	/*
157 	 * Gallium command stream send by virgl is native endian.
158 	 * Because of that we only support little endian guests on
159 	 * little endian hosts.
160 	 */
161 	VIRTIO_GPU_F_VIRGL,
162 #endif
163 	VIRTIO_GPU_F_EDID,
164 };
165 static struct virtio_driver virtio_gpu_driver = {
166 	.feature_table = features,
167 	.feature_table_size = ARRAY_SIZE(features),
168 	.driver.name = KBUILD_MODNAME,
169 	.driver.owner = THIS_MODULE,
170 	.id_table = id_table,
171 	.probe = virtio_gpu_probe,
172 	.remove = virtio_gpu_remove,
173 	.config_changed = virtio_gpu_config_changed
174 };
175 
176 module_virtio_driver(virtio_gpu_driver);
177 
178 MODULE_DEVICE_TABLE(virtio, id_table);
179 MODULE_DESCRIPTION("Virtio GPU driver");
180 MODULE_LICENSE("GPL and additional rights");
181 MODULE_AUTHOR("Dave Airlie <airlied@redhat.com>");
182 MODULE_AUTHOR("Gerd Hoffmann <kraxel@redhat.com>");
183 MODULE_AUTHOR("Alon Levy");
184 
185 static const struct file_operations virtio_gpu_driver_fops = {
186 	.owner = THIS_MODULE,
187 	.open = drm_open,
188 	.mmap = virtio_gpu_mmap,
189 	.poll = drm_poll,
190 	.read = drm_read,
191 	.unlocked_ioctl	= drm_ioctl,
192 	.release = drm_release,
193 	.compat_ioctl = drm_compat_ioctl,
194 	.llseek = noop_llseek,
195 };
196 
197 static struct drm_driver driver = {
198 	.driver_features = DRIVER_MODESET | DRIVER_GEM | DRIVER_PRIME | DRIVER_RENDER | DRIVER_ATOMIC,
199 	.open = virtio_gpu_driver_open,
200 	.postclose = virtio_gpu_driver_postclose,
201 
202 	.dumb_create = virtio_gpu_mode_dumb_create,
203 	.dumb_map_offset = virtio_gpu_mode_dumb_mmap,
204 
205 #if defined(CONFIG_DEBUG_FS)
206 	.debugfs_init = virtio_gpu_debugfs_init,
207 #endif
208 	.prime_handle_to_fd = drm_gem_prime_handle_to_fd,
209 	.prime_fd_to_handle = drm_gem_prime_fd_to_handle,
210 	.gem_prime_export = drm_gem_prime_export,
211 	.gem_prime_import = drm_gem_prime_import,
212 	.gem_prime_get_sg_table = virtgpu_gem_prime_get_sg_table,
213 	.gem_prime_import_sg_table = virtgpu_gem_prime_import_sg_table,
214 	.gem_prime_vmap = virtgpu_gem_prime_vmap,
215 	.gem_prime_vunmap = virtgpu_gem_prime_vunmap,
216 	.gem_prime_mmap = virtgpu_gem_prime_mmap,
217 
218 	.gem_free_object_unlocked = virtio_gpu_gem_free_object,
219 	.gem_open_object = virtio_gpu_gem_object_open,
220 	.gem_close_object = virtio_gpu_gem_object_close,
221 	.fops = &virtio_gpu_driver_fops,
222 
223 	.ioctls = virtio_gpu_ioctls,
224 	.num_ioctls = DRM_VIRTIO_NUM_IOCTLS,
225 
226 	.name = DRIVER_NAME,
227 	.desc = DRIVER_DESC,
228 	.date = DRIVER_DATE,
229 	.major = DRIVER_MAJOR,
230 	.minor = DRIVER_MINOR,
231 	.patchlevel = DRIVER_PATCHLEVEL,
232 };
233