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 #include <linux/screen_info.h> 11 12 #include <drm/drm_aperture.h> 13 #include <drm/drm_atomic_helper.h> 14 #include <drm/drm_drv.h> 15 #include <drm/drm_fbdev_generic.h> 16 #include <drm/drm_gem_shmem_helper.h> 17 #include <drm/drm_simple_kms_helper.h> 18 19 #include "hyperv_drm.h" 20 21 #define DRIVER_NAME "hyperv_drm" 22 #define DRIVER_DESC "DRM driver for Hyper-V synthetic video device" 23 #define DRIVER_DATE "2020" 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 .date = DRIVER_DATE, 35 .major = DRIVER_MAJOR, 36 .minor = DRIVER_MINOR, 37 38 .fops = &hv_fops, 39 DRM_GEM_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 if (IS_ENABLED(CONFIG_SYSFB)) 77 drm_aperture_remove_conflicting_framebuffers(screen_info.lfb_base, 78 screen_info.lfb_size, 79 &hyperv_driver); 80 81 hv->fb_size = (unsigned long)hv->mmio_megabytes * 1024 * 1024; 82 83 ret = vmbus_allocate_mmio(&hv->mem, hdev, 0, -1, hv->fb_size, 0x100000, 84 true); 85 if (ret) { 86 drm_err(dev, "Failed to allocate mmio\n"); 87 return -ENOMEM; 88 } 89 90 /* 91 * Map the VRAM cacheable for performance. This is also required for VM 92 * connect to display properly for ARM64 Linux VM, as the host also maps 93 * the VRAM cacheable. 94 */ 95 hv->vram = ioremap_cache(hv->mem->start, hv->fb_size); 96 if (!hv->vram) { 97 drm_err(dev, "Failed to map vram\n"); 98 ret = -ENOMEM; 99 goto error; 100 } 101 102 hv->fb_base = hv->mem->start; 103 return 0; 104 105 error: 106 vmbus_free_mmio(hv->mem->start, hv->fb_size); 107 return ret; 108 } 109 110 static int hyperv_vmbus_probe(struct hv_device *hdev, 111 const struct hv_vmbus_device_id *dev_id) 112 { 113 struct hyperv_drm_device *hv; 114 struct drm_device *dev; 115 int ret; 116 117 hv = devm_drm_dev_alloc(&hdev->device, &hyperv_driver, 118 struct hyperv_drm_device, dev); 119 if (IS_ERR(hv)) 120 return PTR_ERR(hv); 121 122 dev = &hv->dev; 123 init_completion(&hv->wait); 124 hv_set_drvdata(hdev, hv); 125 hv->hdev = hdev; 126 127 ret = hyperv_connect_vsp(hdev); 128 if (ret) { 129 drm_err(dev, "Failed to connect to vmbus.\n"); 130 goto err_hv_set_drv_data; 131 } 132 133 ret = hyperv_setup_vram(hv, hdev); 134 if (ret) 135 goto err_vmbus_close; 136 137 /* 138 * Should be done only once during init and resume. Failing to update 139 * vram location is not fatal. Device will update dirty area till 140 * preferred resolution only. 141 */ 142 ret = hyperv_update_vram_location(hdev, hv->fb_base); 143 if (ret) 144 drm_warn(dev, "Failed to update vram location.\n"); 145 146 ret = hyperv_mode_config_init(hv); 147 if (ret) 148 goto err_free_mmio; 149 150 ret = drm_dev_register(dev, 0); 151 if (ret) { 152 drm_err(dev, "Failed to register drm driver.\n"); 153 goto err_free_mmio; 154 } 155 156 drm_fbdev_generic_setup(dev, 0); 157 158 return 0; 159 160 err_free_mmio: 161 vmbus_free_mmio(hv->mem->start, hv->fb_size); 162 err_vmbus_close: 163 vmbus_close(hdev->channel); 164 err_hv_set_drv_data: 165 hv_set_drvdata(hdev, NULL); 166 return ret; 167 } 168 169 static void hyperv_vmbus_remove(struct hv_device *hdev) 170 { 171 struct drm_device *dev = hv_get_drvdata(hdev); 172 struct hyperv_drm_device *hv = to_hv(dev); 173 174 drm_dev_unplug(dev); 175 drm_atomic_helper_shutdown(dev); 176 vmbus_close(hdev->channel); 177 hv_set_drvdata(hdev, NULL); 178 179 vmbus_free_mmio(hv->mem->start, hv->fb_size); 180 } 181 182 static void hyperv_vmbus_shutdown(struct hv_device *hdev) 183 { 184 drm_atomic_helper_shutdown(hv_get_drvdata(hdev)); 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 .shutdown = hyperv_vmbus_shutdown, 230 .suspend = hyperv_vmbus_suspend, 231 .resume = hyperv_vmbus_resume, 232 .driver = { 233 .probe_type = PROBE_PREFER_ASYNCHRONOUS, 234 }, 235 }; 236 237 static int __init hyperv_init(void) 238 { 239 int ret; 240 241 if (drm_firmware_drivers_only()) 242 return -ENODEV; 243 244 ret = pci_register_driver(&hyperv_pci_driver); 245 if (ret != 0) 246 return ret; 247 248 return vmbus_driver_register(&hyperv_hv_driver); 249 } 250 251 static void __exit hyperv_exit(void) 252 { 253 vmbus_driver_unregister(&hyperv_hv_driver); 254 pci_unregister_driver(&hyperv_pci_driver); 255 } 256 257 module_init(hyperv_init); 258 module_exit(hyperv_exit); 259 260 MODULE_DEVICE_TABLE(pci, hyperv_pci_tbl); 261 MODULE_DEVICE_TABLE(vmbus, hyperv_vmbus_tbl); 262 MODULE_LICENSE("GPL"); 263 MODULE_AUTHOR("Deepak Rawat <drawat.floss@gmail.com>"); 264 MODULE_DESCRIPTION("DRM driver for Hyper-V synthetic video device"); 265