xref: /linux/drivers/gpu/drm/hyperv/hyperv_drm_drv.c (revision 570f7e331f5febb30f1384817463c7e42b65ca7d)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright 2021 Microsoft
4  */
5 
6 #include <linux/aperture.h>
7 #include <linux/efi.h>
8 #include <linux/hyperv.h>
9 #include <linux/module.h>
10 #include <linux/pci.h>
11 
12 #include <drm/clients/drm_client_setup.h>
13 #include <drm/drm_atomic_helper.h>
14 #include <drm/drm_drv.h>
15 #include <drm/drm_fbdev_shmem.h>
16 #include <drm/drm_gem_shmem_helper.h>
17 #include <drm/drm_print.h>
18 #include <drm/drm_simple_kms_helper.h>
19 
20 #include "hyperv_drm.h"
21 
22 #define DRIVER_NAME "hyperv_drm"
23 #define DRIVER_DESC "DRM driver for Hyper-V synthetic video device"
24 #define DRIVER_MAJOR 1
25 #define DRIVER_MINOR 0
26 
27 DEFINE_DRM_GEM_FOPS(hv_drm_fops);
28 
29 static struct drm_driver hv_drm_driver = {
30 	.driver_features = DRIVER_MODESET | DRIVER_GEM | DRIVER_ATOMIC,
31 
32 	.name		 = DRIVER_NAME,
33 	.desc		 = DRIVER_DESC,
34 	.major		 = DRIVER_MAJOR,
35 	.minor		 = DRIVER_MINOR,
36 
37 	.fops		 = &hv_drm_fops,
38 	DRM_GEM_SHMEM_DRIVER_OPS,
39 	DRM_FBDEV_SHMEM_DRIVER_OPS,
40 };
41 
42 static int hv_drm_pci_probe(struct pci_dev *pdev,
43 			    const struct pci_device_id *ent)
44 {
45 	return 0;
46 }
47 
48 static void hv_drm_pci_remove(struct pci_dev *pdev)
49 {
50 }
51 
52 static const struct pci_device_id hv_drm_pci_tbl[] = {
53 	{
54 		PCI_VDEVICE_SUB(MICROSOFT, PCI_DEVICE_ID_HYPERV_VIDEO,
55 				0, 0),
56 	},
57 	{ /* end of list */ }
58 };
59 MODULE_DEVICE_TABLE(pci, hv_drm_pci_tbl);
60 
61 /*
62  * PCI stub to support gen1 VM.
63  */
64 static struct pci_driver hv_drm_pci_driver = {
65 	.name =		KBUILD_MODNAME,
66 	.id_table =	hv_drm_pci_tbl,
67 	.probe =	hv_drm_pci_probe,
68 	.remove =	hv_drm_pci_remove,
69 };
70 
71 static int hv_drm_setup_vram(struct hv_drm_device *hv,
72 			     struct hv_device *hdev)
73 {
74 	struct drm_device *dev = &hv->dev;
75 	int ret;
76 
77 	hv->fb_size = (unsigned long)hv->mmio_megabytes * 1024 * 1024;
78 
79 	ret = vmbus_allocate_mmio(&hv->mem, hdev, 0, -1, hv->fb_size, 0x100000,
80 				  true);
81 	if (ret) {
82 		drm_err(dev, "Failed to allocate mmio\n");
83 		return -ENOMEM;
84 	}
85 
86 	/*
87 	 * Map the VRAM cacheable for performance. This is also required for VM
88 	 * connect to display properly for ARM64 Linux VM, as the host also maps
89 	 * the VRAM cacheable.
90 	 */
91 	hv->vram = ioremap_cache(hv->mem->start, hv->fb_size);
92 	if (!hv->vram) {
93 		drm_err(dev, "Failed to map vram\n");
94 		ret = -ENOMEM;
95 		goto error;
96 	}
97 
98 	hv->fb_base = hv->mem->start;
99 	return 0;
100 
101 error:
102 	vmbus_free_mmio(hv->mem->start, hv->fb_size);
103 	return ret;
104 }
105 
106 static int hv_drm_vmbus_probe(struct hv_device *hdev,
107 			      const struct hv_vmbus_device_id *dev_id)
108 {
109 	struct hv_drm_device *hv;
110 	struct drm_device *dev;
111 	int ret;
112 
113 	hv = devm_drm_dev_alloc(&hdev->device, &hv_drm_driver,
114 				struct hv_drm_device, dev);
115 	if (IS_ERR(hv))
116 		return PTR_ERR(hv);
117 
118 	dev = &hv->dev;
119 	init_completion(&hv->wait);
120 	hv_set_drvdata(hdev, hv);
121 	hv->hdev = hdev;
122 
123 	ret = hv_drm_connect_vsp(hdev);
124 	if (ret) {
125 		drm_err(dev, "Failed to connect to vmbus.\n");
126 		goto err_hv_set_drv_data;
127 	}
128 
129 	aperture_remove_all_conflicting_devices(hv_drm_driver.name);
130 
131 	ret = hv_drm_setup_vram(hv, hdev);
132 	if (ret)
133 		goto err_vmbus_close;
134 
135 	/*
136 	 * Should be done only once during init and resume. Failing to update
137 	 * vram location is not fatal. Device will update dirty area till
138 	 * preferred resolution only.
139 	 */
140 	ret = hv_drm_update_vram_location(hdev, hv->fb_base);
141 	if (ret)
142 		drm_warn(dev, "Failed to update vram location.\n");
143 
144 	ret = hv_drm_mode_config_init(hv);
145 	if (ret)
146 		goto err_free_mmio;
147 
148 	ret = drm_dev_register(dev, 0);
149 	if (ret) {
150 		drm_err(dev, "Failed to register drm driver.\n");
151 		goto err_free_mmio;
152 	}
153 
154 	/* If DRM panic path is stubbed out VMBus code must do the unload */
155 	if (IS_ENABLED(CONFIG_DRM_PANIC))
156 		vmbus_set_skip_unload(true);
157 
158 	drm_client_setup(dev, NULL);
159 
160 	return 0;
161 
162 err_free_mmio:
163 	iounmap(hv->vram);
164 	vmbus_free_mmio(hv->mem->start, hv->fb_size);
165 err_vmbus_close:
166 	vmbus_close(hdev->channel);
167 err_hv_set_drv_data:
168 	hv_set_drvdata(hdev, NULL);
169 	return ret;
170 }
171 
172 static void hv_drm_vmbus_remove(struct hv_device *hdev)
173 {
174 	struct drm_device *dev = hv_get_drvdata(hdev);
175 	struct hv_drm_device *hv = to_hv_drm(dev);
176 
177 	vmbus_set_skip_unload(false);
178 	drm_dev_unplug(dev);
179 	drm_atomic_helper_shutdown(dev);
180 	vmbus_close(hdev->channel);
181 	hv_set_drvdata(hdev, NULL);
182 
183 	iounmap(hv->vram);
184 	vmbus_free_mmio(hv->mem->start, hv->fb_size);
185 }
186 
187 static void hv_drm_vmbus_shutdown(struct hv_device *hdev)
188 {
189 	drm_atomic_helper_shutdown(hv_get_drvdata(hdev));
190 }
191 
192 static int hv_drm_vmbus_suspend(struct hv_device *hdev)
193 {
194 	struct drm_device *dev = hv_get_drvdata(hdev);
195 	int ret;
196 
197 	ret = drm_mode_config_helper_suspend(dev);
198 	if (ret)
199 		return ret;
200 
201 	vmbus_close(hdev->channel);
202 
203 	return 0;
204 }
205 
206 static int hv_drm_vmbus_resume(struct hv_device *hdev)
207 {
208 	struct drm_device *dev = hv_get_drvdata(hdev);
209 	struct hv_drm_device *hv = to_hv_drm(dev);
210 	int ret;
211 
212 	ret = hv_drm_connect_vsp(hdev);
213 	if (ret)
214 		return ret;
215 
216 	ret = hv_drm_update_vram_location(hdev, hv->fb_base);
217 	if (ret)
218 		return ret;
219 
220 	return drm_mode_config_helper_resume(dev);
221 }
222 
223 static const struct hv_vmbus_device_id hv_drm_vmbus_tbl[] = {
224 	/* Synthetic Video Device GUID */
225 	{HV_SYNTHVID_GUID},
226 	{}
227 };
228 MODULE_DEVICE_TABLE(vmbus, hv_drm_vmbus_tbl);
229 
230 static struct hv_driver hv_drm_hv_driver = {
231 	.name = KBUILD_MODNAME,
232 	.id_table = hv_drm_vmbus_tbl,
233 	.probe = hv_drm_vmbus_probe,
234 	.remove = hv_drm_vmbus_remove,
235 	.shutdown = hv_drm_vmbus_shutdown,
236 	.suspend = hv_drm_vmbus_suspend,
237 	.resume = hv_drm_vmbus_resume,
238 	.driver = {
239 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
240 	},
241 };
242 
243 static int __init hv_drm_init(void)
244 {
245 	int ret;
246 
247 	if (drm_firmware_drivers_only())
248 		return -ENODEV;
249 
250 	ret = pci_register_driver(&hv_drm_pci_driver);
251 	if (ret != 0)
252 		return ret;
253 
254 	ret = vmbus_driver_register(&hv_drm_hv_driver);
255 	if (ret)
256 		pci_unregister_driver(&hv_drm_pci_driver);
257 
258 	return ret;
259 }
260 
261 static void __exit hv_drm_exit(void)
262 {
263 	vmbus_driver_unregister(&hv_drm_hv_driver);
264 	pci_unregister_driver(&hv_drm_pci_driver);
265 }
266 
267 module_init(hv_drm_init);
268 module_exit(hv_drm_exit);
269 
270 MODULE_LICENSE("GPL");
271 MODULE_AUTHOR("Deepak Rawat <drawat.floss@gmail.com>");
272 MODULE_DESCRIPTION("DRM driver for Hyper-V synthetic video device");
273