1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright 2021 Microsoft 4 */ 5 6 #include <linux/efi.h> 7 #include <linux/hyperv.h> 8 #include <linux/module.h> 9 #include <linux/pci.h> 10 11 #include <drm/drm_aperture.h> 12 #include <drm/drm_atomic_helper.h> 13 #include <drm/drm_drv.h> 14 #include <drm/drm_fbdev_generic.h> 15 #include <drm/drm_gem_shmem_helper.h> 16 #include <drm/drm_simple_kms_helper.h> 17 18 #include "hyperv_drm.h" 19 20 #define DRIVER_NAME "hyperv_drm" 21 #define DRIVER_DESC "DRM driver for Hyper-V synthetic video device" 22 #define DRIVER_DATE "2020" 23 #define DRIVER_MAJOR 1 24 #define DRIVER_MINOR 0 25 26 DEFINE_DRM_GEM_FOPS(hv_fops); 27 28 static struct drm_driver hyperv_driver = { 29 .driver_features = DRIVER_MODESET | DRIVER_GEM | DRIVER_ATOMIC, 30 31 .name = DRIVER_NAME, 32 .desc = DRIVER_DESC, 33 .date = DRIVER_DATE, 34 .major = DRIVER_MAJOR, 35 .minor = DRIVER_MINOR, 36 37 .fops = &hv_fops, 38 DRM_GEM_SHMEM_DRIVER_OPS, 39 }; 40 41 static int hyperv_pci_probe(struct pci_dev *pdev, 42 const struct pci_device_id *ent) 43 { 44 return 0; 45 } 46 47 static void hyperv_pci_remove(struct pci_dev *pdev) 48 { 49 } 50 51 static const struct pci_device_id hyperv_pci_tbl[] = { 52 { 53 .vendor = PCI_VENDOR_ID_MICROSOFT, 54 .device = PCI_DEVICE_ID_HYPERV_VIDEO, 55 }, 56 { /* end of list */ } 57 }; 58 59 /* 60 * PCI stub to support gen1 VM. 61 */ 62 static struct pci_driver hyperv_pci_driver = { 63 .name = KBUILD_MODNAME, 64 .id_table = hyperv_pci_tbl, 65 .probe = hyperv_pci_probe, 66 .remove = hyperv_pci_remove, 67 }; 68 69 static int hyperv_setup_vram(struct hyperv_drm_device *hv, 70 struct hv_device *hdev) 71 { 72 struct drm_device *dev = &hv->dev; 73 int ret; 74 75 hv->fb_size = (unsigned long)hv->mmio_megabytes * 1024 * 1024; 76 77 ret = vmbus_allocate_mmio(&hv->mem, hdev, 0, -1, hv->fb_size, 0x100000, 78 true); 79 if (ret) { 80 drm_err(dev, "Failed to allocate mmio\n"); 81 return -ENOMEM; 82 } 83 84 /* 85 * Map the VRAM cacheable for performance. This is also required for VM 86 * connect to display properly for ARM64 Linux VM, as the host also maps 87 * the VRAM cacheable. 88 */ 89 hv->vram = ioremap_cache(hv->mem->start, hv->fb_size); 90 if (!hv->vram) { 91 drm_err(dev, "Failed to map vram\n"); 92 ret = -ENOMEM; 93 goto error; 94 } 95 96 hv->fb_base = hv->mem->start; 97 return 0; 98 99 error: 100 vmbus_free_mmio(hv->mem->start, hv->fb_size); 101 return ret; 102 } 103 104 static int hyperv_vmbus_probe(struct hv_device *hdev, 105 const struct hv_vmbus_device_id *dev_id) 106 { 107 struct hyperv_drm_device *hv; 108 struct drm_device *dev; 109 int ret; 110 111 hv = devm_drm_dev_alloc(&hdev->device, &hyperv_driver, 112 struct hyperv_drm_device, dev); 113 if (IS_ERR(hv)) 114 return PTR_ERR(hv); 115 116 dev = &hv->dev; 117 init_completion(&hv->wait); 118 hv_set_drvdata(hdev, hv); 119 hv->hdev = hdev; 120 121 ret = hyperv_connect_vsp(hdev); 122 if (ret) { 123 drm_err(dev, "Failed to connect to vmbus.\n"); 124 goto err_hv_set_drv_data; 125 } 126 127 drm_aperture_remove_framebuffers(&hyperv_driver); 128 129 ret = hyperv_setup_vram(hv, hdev); 130 if (ret) 131 goto err_vmbus_close; 132 133 /* 134 * Should be done only once during init and resume. Failing to update 135 * vram location is not fatal. Device will update dirty area till 136 * preferred resolution only. 137 */ 138 ret = hyperv_update_vram_location(hdev, hv->fb_base); 139 if (ret) 140 drm_warn(dev, "Failed to update vram location.\n"); 141 142 ret = hyperv_mode_config_init(hv); 143 if (ret) 144 goto err_free_mmio; 145 146 ret = drm_dev_register(dev, 0); 147 if (ret) { 148 drm_err(dev, "Failed to register drm driver.\n"); 149 goto err_free_mmio; 150 } 151 152 drm_fbdev_generic_setup(dev, 0); 153 154 return 0; 155 156 err_free_mmio: 157 vmbus_free_mmio(hv->mem->start, hv->fb_size); 158 err_vmbus_close: 159 vmbus_close(hdev->channel); 160 err_hv_set_drv_data: 161 hv_set_drvdata(hdev, NULL); 162 return ret; 163 } 164 165 static void hyperv_vmbus_remove(struct hv_device *hdev) 166 { 167 struct drm_device *dev = hv_get_drvdata(hdev); 168 struct hyperv_drm_device *hv = to_hv(dev); 169 170 drm_dev_unplug(dev); 171 drm_atomic_helper_shutdown(dev); 172 vmbus_close(hdev->channel); 173 hv_set_drvdata(hdev, NULL); 174 175 vmbus_free_mmio(hv->mem->start, hv->fb_size); 176 } 177 178 static void hyperv_vmbus_shutdown(struct hv_device *hdev) 179 { 180 drm_atomic_helper_shutdown(hv_get_drvdata(hdev)); 181 } 182 183 static int hyperv_vmbus_suspend(struct hv_device *hdev) 184 { 185 struct drm_device *dev = hv_get_drvdata(hdev); 186 int ret; 187 188 ret = drm_mode_config_helper_suspend(dev); 189 if (ret) 190 return ret; 191 192 vmbus_close(hdev->channel); 193 194 return 0; 195 } 196 197 static int hyperv_vmbus_resume(struct hv_device *hdev) 198 { 199 struct drm_device *dev = hv_get_drvdata(hdev); 200 struct hyperv_drm_device *hv = to_hv(dev); 201 int ret; 202 203 ret = hyperv_connect_vsp(hdev); 204 if (ret) 205 return ret; 206 207 ret = hyperv_update_vram_location(hdev, hv->fb_base); 208 if (ret) 209 return ret; 210 211 return drm_mode_config_helper_resume(dev); 212 } 213 214 static const struct hv_vmbus_device_id hyperv_vmbus_tbl[] = { 215 /* Synthetic Video Device GUID */ 216 {HV_SYNTHVID_GUID}, 217 {} 218 }; 219 220 static struct hv_driver hyperv_hv_driver = { 221 .name = KBUILD_MODNAME, 222 .id_table = hyperv_vmbus_tbl, 223 .probe = hyperv_vmbus_probe, 224 .remove = hyperv_vmbus_remove, 225 .shutdown = hyperv_vmbus_shutdown, 226 .suspend = hyperv_vmbus_suspend, 227 .resume = hyperv_vmbus_resume, 228 .driver = { 229 .probe_type = PROBE_PREFER_ASYNCHRONOUS, 230 }, 231 }; 232 233 static int __init hyperv_init(void) 234 { 235 int ret; 236 237 if (drm_firmware_drivers_only()) 238 return -ENODEV; 239 240 ret = pci_register_driver(&hyperv_pci_driver); 241 if (ret != 0) 242 return ret; 243 244 return vmbus_driver_register(&hyperv_hv_driver); 245 } 246 247 static void __exit hyperv_exit(void) 248 { 249 vmbus_driver_unregister(&hyperv_hv_driver); 250 pci_unregister_driver(&hyperv_pci_driver); 251 } 252 253 module_init(hyperv_init); 254 module_exit(hyperv_exit); 255 256 MODULE_DEVICE_TABLE(pci, hyperv_pci_tbl); 257 MODULE_DEVICE_TABLE(vmbus, hyperv_vmbus_tbl); 258 MODULE_LICENSE("GPL"); 259 MODULE_AUTHOR("Deepak Rawat <drawat.floss@gmail.com>"); 260 MODULE_DESCRIPTION("DRM driver for Hyper-V synthetic video device"); 261