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_fb_helper.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 PCI_VENDOR_ID_MICROSOFT 0x1414 27 #define PCI_DEVICE_ID_HYPERV_VIDEO 0x5353 28 29 DEFINE_DRM_GEM_FOPS(hv_fops); 30 31 static struct drm_driver hyperv_driver = { 32 .driver_features = DRIVER_MODESET | DRIVER_GEM | DRIVER_ATOMIC, 33 34 .name = DRIVER_NAME, 35 .desc = DRIVER_DESC, 36 .date = DRIVER_DATE, 37 .major = DRIVER_MAJOR, 38 .minor = DRIVER_MINOR, 39 40 .fops = &hv_fops, 41 DRM_GEM_SHMEM_DRIVER_OPS, 42 }; 43 44 static int hyperv_pci_probe(struct pci_dev *pdev, 45 const struct pci_device_id *ent) 46 { 47 return 0; 48 } 49 50 static void hyperv_pci_remove(struct pci_dev *pdev) 51 { 52 } 53 54 static const struct pci_device_id hyperv_pci_tbl[] = { 55 { 56 .vendor = PCI_VENDOR_ID_MICROSOFT, 57 .device = PCI_DEVICE_ID_HYPERV_VIDEO, 58 }, 59 { /* end of list */ } 60 }; 61 62 /* 63 * PCI stub to support gen1 VM. 64 */ 65 static struct pci_driver hyperv_pci_driver = { 66 .name = KBUILD_MODNAME, 67 .id_table = hyperv_pci_tbl, 68 .probe = hyperv_pci_probe, 69 .remove = hyperv_pci_remove, 70 }; 71 72 static int hyperv_setup_vram(struct hyperv_drm_device *hv, 73 struct hv_device *hdev) 74 { 75 struct drm_device *dev = &hv->dev; 76 int ret; 77 78 drm_aperture_remove_conflicting_framebuffers(screen_info.lfb_base, 79 screen_info.lfb_size, 80 false, 81 &hyperv_driver); 82 83 hv->fb_size = (unsigned long)hv->mmio_megabytes * 1024 * 1024; 84 85 ret = vmbus_allocate_mmio(&hv->mem, hdev, 0, -1, hv->fb_size, 0x100000, 86 true); 87 if (ret) { 88 drm_err(dev, "Failed to allocate mmio\n"); 89 return -ENOMEM; 90 } 91 92 /* 93 * Map the VRAM cacheable for performance. This is also required for VM 94 * connect to display properly for ARM64 Linux VM, as the host also maps 95 * the VRAM cacheable. 96 */ 97 hv->vram = ioremap_cache(hv->mem->start, hv->fb_size); 98 if (!hv->vram) { 99 drm_err(dev, "Failed to map vram\n"); 100 ret = -ENOMEM; 101 goto error; 102 } 103 104 hv->fb_base = hv->mem->start; 105 return 0; 106 107 error: 108 vmbus_free_mmio(hv->mem->start, hv->fb_size); 109 return ret; 110 } 111 112 static int hyperv_vmbus_probe(struct hv_device *hdev, 113 const struct hv_vmbus_device_id *dev_id) 114 { 115 struct hyperv_drm_device *hv; 116 struct drm_device *dev; 117 int ret; 118 119 hv = devm_drm_dev_alloc(&hdev->device, &hyperv_driver, 120 struct hyperv_drm_device, dev); 121 if (IS_ERR(hv)) 122 return PTR_ERR(hv); 123 124 dev = &hv->dev; 125 init_completion(&hv->wait); 126 hv_set_drvdata(hdev, hv); 127 hv->hdev = hdev; 128 129 ret = hyperv_connect_vsp(hdev); 130 if (ret) { 131 drm_err(dev, "Failed to connect to vmbus.\n"); 132 goto err_hv_set_drv_data; 133 } 134 135 ret = hyperv_setup_vram(hv, hdev); 136 137 if (ret) 138 goto err_vmbus_close; 139 140 /* 141 * Should be done only once during init and resume. Failing to update 142 * vram location is not fatal. Device will update dirty area till 143 * preferred resolution only. 144 */ 145 ret = hyperv_update_vram_location(hdev, hv->fb_base); 146 if (ret) 147 drm_warn(dev, "Failed to update vram location.\n"); 148 149 hv->dirt_needed = true; 150 151 ret = hyperv_mode_config_init(hv); 152 if (ret) 153 goto err_vmbus_close; 154 155 ret = drm_dev_register(dev, 0); 156 if (ret) { 157 drm_err(dev, "Failed to register drm driver.\n"); 158 goto err_vmbus_close; 159 } 160 161 drm_fbdev_generic_setup(dev, 0); 162 163 return 0; 164 165 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 int hyperv_vmbus_remove(struct hv_device *hdev) 173 { 174 struct drm_device *dev = hv_get_drvdata(hdev); 175 struct hyperv_drm_device *hv = to_hv(dev); 176 177 drm_dev_unplug(dev); 178 drm_atomic_helper_shutdown(dev); 179 vmbus_close(hdev->channel); 180 hv_set_drvdata(hdev, NULL); 181 182 vmbus_free_mmio(hv->mem->start, hv->fb_size); 183 184 return 0; 185 } 186 187 static int hyperv_vmbus_suspend(struct hv_device *hdev) 188 { 189 struct drm_device *dev = hv_get_drvdata(hdev); 190 int ret; 191 192 ret = drm_mode_config_helper_suspend(dev); 193 if (ret) 194 return ret; 195 196 vmbus_close(hdev->channel); 197 198 return 0; 199 } 200 201 static int hyperv_vmbus_resume(struct hv_device *hdev) 202 { 203 struct drm_device *dev = hv_get_drvdata(hdev); 204 struct hyperv_drm_device *hv = to_hv(dev); 205 int ret; 206 207 ret = hyperv_connect_vsp(hdev); 208 if (ret) 209 return ret; 210 211 ret = hyperv_update_vram_location(hdev, hv->fb_base); 212 if (ret) 213 return ret; 214 215 return drm_mode_config_helper_resume(dev); 216 } 217 218 static const struct hv_vmbus_device_id hyperv_vmbus_tbl[] = { 219 /* Synthetic Video Device GUID */ 220 {HV_SYNTHVID_GUID}, 221 {} 222 }; 223 224 static struct hv_driver hyperv_hv_driver = { 225 .name = KBUILD_MODNAME, 226 .id_table = hyperv_vmbus_tbl, 227 .probe = hyperv_vmbus_probe, 228 .remove = hyperv_vmbus_remove, 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