xref: /linux/drivers/gpu/drm/hyperv/hyperv_drm_drv.c (revision 815e260a18a3af4dab59025ee99a7156c0e8b5e0)
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_fops);
28 
29 static struct drm_driver hyperv_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_fops,
38 	DRM_GEM_SHMEM_DRIVER_OPS,
39 	DRM_FBDEV_SHMEM_DRIVER_OPS,
40 };
41 
42 static int hyperv_pci_probe(struct pci_dev *pdev,
43 			    const struct pci_device_id *ent)
44 {
45 	return 0;
46 }
47 
48 static void hyperv_pci_remove(struct pci_dev *pdev)
49 {
50 }
51 
52 static const struct pci_device_id hyperv_pci_tbl[] = {
53 	{
54 		.vendor = PCI_VENDOR_ID_MICROSOFT,
55 		.device = PCI_DEVICE_ID_HYPERV_VIDEO,
56 	},
57 	{ /* end of list */ }
58 };
59 
60 /*
61  * PCI stub to support gen1 VM.
62  */
63 static struct pci_driver hyperv_pci_driver = {
64 	.name =		KBUILD_MODNAME,
65 	.id_table =	hyperv_pci_tbl,
66 	.probe =	hyperv_pci_probe,
67 	.remove =	hyperv_pci_remove,
68 };
69 
70 static int hyperv_setup_vram(struct hyperv_drm_device *hv,
71 			     struct hv_device *hdev)
72 {
73 	struct drm_device *dev = &hv->dev;
74 	int ret;
75 
76 	hv->fb_size = (unsigned long)hv->mmio_megabytes * 1024 * 1024;
77 
78 	ret = vmbus_allocate_mmio(&hv->mem, hdev, 0, -1, hv->fb_size, 0x100000,
79 				  true);
80 	if (ret) {
81 		drm_err(dev, "Failed to allocate mmio\n");
82 		return -ENOMEM;
83 	}
84 
85 	/*
86 	 * Map the VRAM cacheable for performance. This is also required for VM
87 	 * connect to display properly for ARM64 Linux VM, as the host also maps
88 	 * the VRAM cacheable.
89 	 */
90 	hv->vram = ioremap_cache(hv->mem->start, hv->fb_size);
91 	if (!hv->vram) {
92 		drm_err(dev, "Failed to map vram\n");
93 		ret = -ENOMEM;
94 		goto error;
95 	}
96 
97 	hv->fb_base = hv->mem->start;
98 	return 0;
99 
100 error:
101 	vmbus_free_mmio(hv->mem->start, hv->fb_size);
102 	return ret;
103 }
104 
105 static int hyperv_vmbus_probe(struct hv_device *hdev,
106 			      const struct hv_vmbus_device_id *dev_id)
107 {
108 	struct hyperv_drm_device *hv;
109 	struct drm_device *dev;
110 	int ret;
111 
112 	hv = devm_drm_dev_alloc(&hdev->device, &hyperv_driver,
113 				struct hyperv_drm_device, dev);
114 	if (IS_ERR(hv))
115 		return PTR_ERR(hv);
116 
117 	dev = &hv->dev;
118 	init_completion(&hv->wait);
119 	hv_set_drvdata(hdev, hv);
120 	hv->hdev = hdev;
121 
122 	ret = hyperv_connect_vsp(hdev);
123 	if (ret) {
124 		drm_err(dev, "Failed to connect to vmbus.\n");
125 		goto err_hv_set_drv_data;
126 	}
127 
128 	aperture_remove_all_conflicting_devices(hyperv_driver.name);
129 
130 	ret = hyperv_setup_vram(hv, hdev);
131 	if (ret)
132 		goto err_vmbus_close;
133 
134 	/*
135 	 * Should be done only once during init and resume. Failing to update
136 	 * vram location is not fatal. Device will update dirty area till
137 	 * preferred resolution only.
138 	 */
139 	ret = hyperv_update_vram_location(hdev, hv->fb_base);
140 	if (ret)
141 		drm_warn(dev, "Failed to update vram location.\n");
142 
143 	ret = hyperv_mode_config_init(hv);
144 	if (ret)
145 		goto err_free_mmio;
146 
147 	ret = drm_dev_register(dev, 0);
148 	if (ret) {
149 		drm_err(dev, "Failed to register drm driver.\n");
150 		goto err_free_mmio;
151 	}
152 
153 	drm_client_setup(dev, NULL);
154 
155 	return 0;
156 
157 err_free_mmio:
158 	iounmap(hv->vram);
159 	vmbus_free_mmio(hv->mem->start, hv->fb_size);
160 err_vmbus_close:
161 	vmbus_close(hdev->channel);
162 err_hv_set_drv_data:
163 	hv_set_drvdata(hdev, NULL);
164 	return ret;
165 }
166 
167 static void hyperv_vmbus_remove(struct hv_device *hdev)
168 {
169 	struct drm_device *dev = hv_get_drvdata(hdev);
170 	struct hyperv_drm_device *hv = to_hv(dev);
171 
172 	drm_dev_unplug(dev);
173 	drm_atomic_helper_shutdown(dev);
174 	vmbus_close(hdev->channel);
175 	hv_set_drvdata(hdev, NULL);
176 
177 	iounmap(hv->vram);
178 	vmbus_free_mmio(hv->mem->start, hv->fb_size);
179 }
180 
181 static void hyperv_vmbus_shutdown(struct hv_device *hdev)
182 {
183 	drm_atomic_helper_shutdown(hv_get_drvdata(hdev));
184 }
185 
186 static int hyperv_vmbus_suspend(struct hv_device *hdev)
187 {
188 	struct drm_device *dev = hv_get_drvdata(hdev);
189 	int ret;
190 
191 	ret = drm_mode_config_helper_suspend(dev);
192 	if (ret)
193 		return ret;
194 
195 	vmbus_close(hdev->channel);
196 
197 	return 0;
198 }
199 
200 static int hyperv_vmbus_resume(struct hv_device *hdev)
201 {
202 	struct drm_device *dev = hv_get_drvdata(hdev);
203 	struct hyperv_drm_device *hv = to_hv(dev);
204 	int ret;
205 
206 	ret = hyperv_connect_vsp(hdev);
207 	if (ret)
208 		return ret;
209 
210 	ret = hyperv_update_vram_location(hdev, hv->fb_base);
211 	if (ret)
212 		return ret;
213 
214 	return drm_mode_config_helper_resume(dev);
215 }
216 
217 static const struct hv_vmbus_device_id hyperv_vmbus_tbl[] = {
218 	/* Synthetic Video Device GUID */
219 	{HV_SYNTHVID_GUID},
220 	{}
221 };
222 
223 static struct hv_driver hyperv_hv_driver = {
224 	.name = KBUILD_MODNAME,
225 	.id_table = hyperv_vmbus_tbl,
226 	.probe = hyperv_vmbus_probe,
227 	.remove = hyperv_vmbus_remove,
228 	.shutdown = hyperv_vmbus_shutdown,
229 	.suspend = hyperv_vmbus_suspend,
230 	.resume = hyperv_vmbus_resume,
231 	.driver = {
232 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
233 	},
234 };
235 
236 static int __init hyperv_init(void)
237 {
238 	int ret;
239 
240 	if (drm_firmware_drivers_only())
241 		return -ENODEV;
242 
243 	ret = pci_register_driver(&hyperv_pci_driver);
244 	if (ret != 0)
245 		return ret;
246 
247 	return vmbus_driver_register(&hyperv_hv_driver);
248 }
249 
250 static void __exit hyperv_exit(void)
251 {
252 	vmbus_driver_unregister(&hyperv_hv_driver);
253 	pci_unregister_driver(&hyperv_pci_driver);
254 }
255 
256 module_init(hyperv_init);
257 module_exit(hyperv_exit);
258 
259 MODULE_DEVICE_TABLE(pci, hyperv_pci_tbl);
260 MODULE_DEVICE_TABLE(vmbus, hyperv_vmbus_tbl);
261 MODULE_LICENSE("GPL");
262 MODULE_AUTHOR("Deepak Rawat <drawat.floss@gmail.com>");
263 MODULE_DESCRIPTION("DRM driver for Hyper-V synthetic video device");
264