1 /* $NetBSD: virtgpu_drv.c,v 1.3 2021/12/18 23:45:45 riastradh Exp $ */
2
3 /*
4 * Copyright (C) 2015 Red Hat, Inc.
5 * All Rights Reserved.
6 *
7 * Authors:
8 * Dave Airlie <airlied@redhat.com>
9 * Gerd Hoffmann <kraxel@redhat.com>
10 *
11 * Permission is hereby granted, free of charge, to any person obtaining a
12 * copy of this software and associated documentation files (the "Software"),
13 * to deal in the Software without restriction, including without limitation
14 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
15 * and/or sell copies of the Software, and to permit persons to whom the
16 * Software is furnished to do so, subject to the following conditions:
17 *
18 * The above copyright notice and this permission notice (including the next
19 * paragraph) shall be included in all copies or substantial portions of the
20 * Software.
21 *
22 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
23 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
24 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
25 * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
26 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
27 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
28 * OTHER DEALINGS IN THE SOFTWARE.
29 */
30
31 #include <sys/cdefs.h>
32 __KERNEL_RCSID(0, "$NetBSD: virtgpu_drv.c,v 1.3 2021/12/18 23:45:45 riastradh Exp $");
33
34 #include <linux/module.h>
35 #include <linux/console.h>
36 #include <linux/pci.h>
37
38 #include <drm/drm.h>
39 #include <drm/drm_drv.h>
40 #include <drm/drm_file.h>
41
42 #include "virtgpu_drv.h"
43
44 static struct drm_driver driver;
45
46 static int virtio_gpu_modeset = -1;
47
48 MODULE_PARM_DESC(modeset, "Disable/Enable modesetting");
49 module_param_named(modeset, virtio_gpu_modeset, int, 0400);
50
virtio_gpu_pci_quirk(struct drm_device * dev,struct virtio_device * vdev)51 static int virtio_gpu_pci_quirk(struct drm_device *dev, struct virtio_device *vdev)
52 {
53 struct pci_dev *pdev = to_pci_dev(vdev->dev.parent);
54 const char *pname = dev_name(&pdev->dev);
55 bool vga = (pdev->class >> 8) == PCI_CLASS_DISPLAY_VGA;
56 char unique[20];
57
58 DRM_INFO("pci: %s detected at %s\n",
59 vga ? "virtio-vga" : "virtio-gpu-pci",
60 pname);
61 dev->pdev = pdev;
62 if (vga)
63 drm_fb_helper_remove_conflicting_pci_framebuffers(pdev,
64 "virtiodrmfb");
65
66 /*
67 * Normally the drm_dev_set_unique() call is done by core DRM.
68 * The following comment covers, why virtio cannot rely on it.
69 *
70 * Unlike the other virtual GPU drivers, virtio abstracts the
71 * underlying bus type by using struct virtio_device.
72 *
73 * Hence the dev_is_pci() check, used in core DRM, will fail
74 * and the unique returned will be the virtio_device "virtio0",
75 * while a "pci:..." one is required.
76 *
77 * A few other ideas were considered:
78 * - Extend the dev_is_pci() check [in drm_set_busid] to
79 * consider virtio.
80 * Seems like a bigger hack than what we have already.
81 *
82 * - Point drm_device::dev to the parent of the virtio_device
83 * Semantic changes:
84 * * Using the wrong device for i2c, framebuffer_alloc and
85 * prime import.
86 * Visual changes:
87 * * Helpers such as DRM_DEV_ERROR, dev_info, drm_printer,
88 * will print the wrong information.
89 *
90 * We could address the latter issues, by introducing
91 * drm_device::bus_dev, ... which would be used solely for this.
92 *
93 * So for the moment keep things as-is, with a bulky comment
94 * for the next person who feels like removing this
95 * drm_dev_set_unique() quirk.
96 */
97 snprintf(unique, sizeof(unique), "pci:%s", pname);
98 return drm_dev_set_unique(dev, unique);
99 }
100
virtio_gpu_probe(struct virtio_device * vdev)101 static int virtio_gpu_probe(struct virtio_device *vdev)
102 {
103 struct drm_device *dev;
104 int ret;
105
106 if (vgacon_text_force() && virtio_gpu_modeset == -1)
107 return -EINVAL;
108
109 if (virtio_gpu_modeset == 0)
110 return -EINVAL;
111
112 dev = drm_dev_alloc(&driver, &vdev->dev);
113 if (IS_ERR(dev))
114 return PTR_ERR(dev);
115 vdev->priv = dev;
116
117 if (!strcmp(vdev->dev.parent->bus->name, "pci")) {
118 ret = virtio_gpu_pci_quirk(dev, vdev);
119 if (ret)
120 goto err_free;
121 }
122
123 ret = virtio_gpu_init(dev);
124 if (ret)
125 goto err_free;
126
127 ret = drm_dev_register(dev, 0);
128 if (ret)
129 goto err_free;
130
131 drm_fbdev_generic_setup(vdev->priv, 32);
132 return 0;
133
134 err_free:
135 drm_dev_put(dev);
136 return ret;
137 }
138
virtio_gpu_remove(struct virtio_device * vdev)139 static void virtio_gpu_remove(struct virtio_device *vdev)
140 {
141 struct drm_device *dev = vdev->priv;
142
143 drm_dev_unregister(dev);
144 virtio_gpu_deinit(dev);
145 drm_dev_put(dev);
146 }
147
virtio_gpu_config_changed(struct virtio_device * vdev)148 static void virtio_gpu_config_changed(struct virtio_device *vdev)
149 {
150 struct drm_device *dev = vdev->priv;
151 struct virtio_gpu_device *vgdev = dev->dev_private;
152
153 schedule_work(&vgdev->config_changed_work);
154 }
155
156 static struct virtio_device_id id_table[] = {
157 { VIRTIO_ID_GPU, VIRTIO_DEV_ANY_ID },
158 { 0 },
159 };
160
161 static unsigned int features[] = {
162 #ifdef __LITTLE_ENDIAN
163 /*
164 * Gallium command stream send by virgl is native endian.
165 * Because of that we only support little endian guests on
166 * little endian hosts.
167 */
168 VIRTIO_GPU_F_VIRGL,
169 #endif
170 VIRTIO_GPU_F_EDID,
171 };
172 static struct virtio_driver virtio_gpu_driver = {
173 .feature_table = features,
174 .feature_table_size = ARRAY_SIZE(features),
175 .driver.name = KBUILD_MODNAME,
176 .driver.owner = THIS_MODULE,
177 .id_table = id_table,
178 .probe = virtio_gpu_probe,
179 .remove = virtio_gpu_remove,
180 .config_changed = virtio_gpu_config_changed
181 };
182
183 module_virtio_driver(virtio_gpu_driver);
184
185 MODULE_DEVICE_TABLE(virtio, id_table);
186 MODULE_DESCRIPTION("Virtio GPU driver");
187 MODULE_LICENSE("GPL and additional rights");
188 MODULE_AUTHOR("Dave Airlie <airlied@redhat.com>");
189 MODULE_AUTHOR("Gerd Hoffmann <kraxel@redhat.com>");
190 MODULE_AUTHOR("Alon Levy");
191
192 DEFINE_DRM_GEM_FOPS(virtio_gpu_driver_fops);
193
194 static struct drm_driver driver = {
195 .driver_features = DRIVER_MODESET | DRIVER_GEM | DRIVER_RENDER | DRIVER_ATOMIC,
196 .open = virtio_gpu_driver_open,
197 .postclose = virtio_gpu_driver_postclose,
198
199 .dumb_create = virtio_gpu_mode_dumb_create,
200 .dumb_map_offset = virtio_gpu_mode_dumb_mmap,
201
202 #if defined(CONFIG_DEBUG_FS)
203 .debugfs_init = virtio_gpu_debugfs_init,
204 #endif
205 .prime_handle_to_fd = drm_gem_prime_handle_to_fd,
206 .prime_fd_to_handle = drm_gem_prime_fd_to_handle,
207 .gem_prime_mmap = drm_gem_prime_mmap,
208 .gem_prime_import_sg_table = virtgpu_gem_prime_import_sg_table,
209
210 .gem_create_object = virtio_gpu_create_object,
211 .fops = &virtio_gpu_driver_fops,
212
213 .ioctls = virtio_gpu_ioctls,
214 .num_ioctls = DRM_VIRTIO_NUM_IOCTLS,
215
216 .name = DRIVER_NAME,
217 .desc = DRIVER_DESC,
218 .date = DRIVER_DATE,
219 .major = DRIVER_MAJOR,
220 .minor = DRIVER_MINOR,
221 .patchlevel = DRIVER_PATCHLEVEL,
222 };
223