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 drm_aperture_remove_conflicting_framebuffers(screen_info.lfb_base, 77 screen_info.lfb_size, 78 &hyperv_driver); 79 80 hv->fb_size = (unsigned long)hv->mmio_megabytes * 1024 * 1024; 81 82 ret = vmbus_allocate_mmio(&hv->mem, hdev, 0, -1, hv->fb_size, 0x100000, 83 true); 84 if (ret) { 85 drm_err(dev, "Failed to allocate mmio\n"); 86 return -ENOMEM; 87 } 88 89 /* 90 * Map the VRAM cacheable for performance. This is also required for VM 91 * connect to display properly for ARM64 Linux VM, as the host also maps 92 * the VRAM cacheable. 93 */ 94 hv->vram = ioremap_cache(hv->mem->start, hv->fb_size); 95 if (!hv->vram) { 96 drm_err(dev, "Failed to map vram\n"); 97 ret = -ENOMEM; 98 goto error; 99 } 100 101 hv->fb_base = hv->mem->start; 102 return 0; 103 104 error: 105 vmbus_free_mmio(hv->mem->start, hv->fb_size); 106 return ret; 107 } 108 109 static int hyperv_vmbus_probe(struct hv_device *hdev, 110 const struct hv_vmbus_device_id *dev_id) 111 { 112 struct hyperv_drm_device *hv; 113 struct drm_device *dev; 114 int ret; 115 116 hv = devm_drm_dev_alloc(&hdev->device, &hyperv_driver, 117 struct hyperv_drm_device, dev); 118 if (IS_ERR(hv)) 119 return PTR_ERR(hv); 120 121 dev = &hv->dev; 122 init_completion(&hv->wait); 123 hv_set_drvdata(hdev, hv); 124 hv->hdev = hdev; 125 126 ret = hyperv_connect_vsp(hdev); 127 if (ret) { 128 drm_err(dev, "Failed to connect to vmbus.\n"); 129 goto err_hv_set_drv_data; 130 } 131 132 ret = hyperv_setup_vram(hv, hdev); 133 if (ret) 134 goto err_vmbus_close; 135 136 /* 137 * Should be done only once during init and resume. Failing to update 138 * vram location is not fatal. Device will update dirty area till 139 * preferred resolution only. 140 */ 141 ret = hyperv_update_vram_location(hdev, hv->fb_base); 142 if (ret) 143 drm_warn(dev, "Failed to update vram location.\n"); 144 145 ret = hyperv_mode_config_init(hv); 146 if (ret) 147 goto err_free_mmio; 148 149 ret = drm_dev_register(dev, 0); 150 if (ret) { 151 drm_err(dev, "Failed to register drm driver.\n"); 152 goto err_free_mmio; 153 } 154 155 drm_fbdev_generic_setup(dev, 0); 156 157 return 0; 158 159 err_free_mmio: 160 vmbus_free_mmio(hv->mem->start, hv->fb_size); 161 err_vmbus_close: 162 vmbus_close(hdev->channel); 163 err_hv_set_drv_data: 164 hv_set_drvdata(hdev, NULL); 165 return ret; 166 } 167 168 static void hyperv_vmbus_remove(struct hv_device *hdev) 169 { 170 struct drm_device *dev = hv_get_drvdata(hdev); 171 struct hyperv_drm_device *hv = to_hv(dev); 172 173 drm_dev_unplug(dev); 174 drm_atomic_helper_shutdown(dev); 175 vmbus_close(hdev->channel); 176 hv_set_drvdata(hdev, NULL); 177 178 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