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