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 drm_aperture_remove_conflicting_framebuffers(screen_info.lfb_base, 76 screen_info.lfb_size, 77 &hyperv_driver); 78 79 hv->fb_size = (unsigned long)hv->mmio_megabytes * 1024 * 1024; 80 81 ret = vmbus_allocate_mmio(&hv->mem, hdev, 0, -1, hv->fb_size, 0x100000, 82 true); 83 if (ret) { 84 drm_err(dev, "Failed to allocate mmio\n"); 85 return -ENOMEM; 86 } 87 88 /* 89 * Map the VRAM cacheable for performance. This is also required for VM 90 * connect to display properly for ARM64 Linux VM, as the host also maps 91 * the VRAM cacheable. 92 */ 93 hv->vram = ioremap_cache(hv->mem->start, hv->fb_size); 94 if (!hv->vram) { 95 drm_err(dev, "Failed to map vram\n"); 96 ret = -ENOMEM; 97 goto error; 98 } 99 100 hv->fb_base = hv->mem->start; 101 return 0; 102 103 error: 104 vmbus_free_mmio(hv->mem->start, hv->fb_size); 105 return ret; 106 } 107 108 static int hyperv_vmbus_probe(struct hv_device *hdev, 109 const struct hv_vmbus_device_id *dev_id) 110 { 111 struct hyperv_drm_device *hv; 112 struct drm_device *dev; 113 int ret; 114 115 hv = devm_drm_dev_alloc(&hdev->device, &hyperv_driver, 116 struct hyperv_drm_device, dev); 117 if (IS_ERR(hv)) 118 return PTR_ERR(hv); 119 120 dev = &hv->dev; 121 init_completion(&hv->wait); 122 hv_set_drvdata(hdev, hv); 123 hv->hdev = hdev; 124 125 ret = hyperv_connect_vsp(hdev); 126 if (ret) { 127 drm_err(dev, "Failed to connect to vmbus.\n"); 128 goto err_hv_set_drv_data; 129 } 130 131 ret = hyperv_setup_vram(hv, hdev); 132 if (ret) 133 goto err_vmbus_close; 134 135 /* 136 * Should be done only once during init and resume. Failing to update 137 * vram location is not fatal. Device will update dirty area till 138 * preferred resolution only. 139 */ 140 ret = hyperv_update_vram_location(hdev, hv->fb_base); 141 if (ret) 142 drm_warn(dev, "Failed to update vram location.\n"); 143 144 ret = hyperv_mode_config_init(hv); 145 if (ret) 146 goto err_free_mmio; 147 148 ret = drm_dev_register(dev, 0); 149 if (ret) { 150 drm_err(dev, "Failed to register drm driver.\n"); 151 goto err_free_mmio; 152 } 153 154 drm_fbdev_generic_setup(dev, 0); 155 156 return 0; 157 158 err_free_mmio: 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 vmbus_free_mmio(hv->mem->start, hv->fb_size); 178 } 179 180 static int hyperv_vmbus_suspend(struct hv_device *hdev) 181 { 182 struct drm_device *dev = hv_get_drvdata(hdev); 183 int ret; 184 185 ret = drm_mode_config_helper_suspend(dev); 186 if (ret) 187 return ret; 188 189 vmbus_close(hdev->channel); 190 191 return 0; 192 } 193 194 static int hyperv_vmbus_resume(struct hv_device *hdev) 195 { 196 struct drm_device *dev = hv_get_drvdata(hdev); 197 struct hyperv_drm_device *hv = to_hv(dev); 198 int ret; 199 200 ret = hyperv_connect_vsp(hdev); 201 if (ret) 202 return ret; 203 204 ret = hyperv_update_vram_location(hdev, hv->fb_base); 205 if (ret) 206 return ret; 207 208 return drm_mode_config_helper_resume(dev); 209 } 210 211 static const struct hv_vmbus_device_id hyperv_vmbus_tbl[] = { 212 /* Synthetic Video Device GUID */ 213 {HV_SYNTHVID_GUID}, 214 {} 215 }; 216 217 static struct hv_driver hyperv_hv_driver = { 218 .name = KBUILD_MODNAME, 219 .id_table = hyperv_vmbus_tbl, 220 .probe = hyperv_vmbus_probe, 221 .remove = hyperv_vmbus_remove, 222 .suspend = hyperv_vmbus_suspend, 223 .resume = hyperv_vmbus_resume, 224 .driver = { 225 .probe_type = PROBE_PREFER_ASYNCHRONOUS, 226 }, 227 }; 228 229 static int __init hyperv_init(void) 230 { 231 int ret; 232 233 if (drm_firmware_drivers_only()) 234 return -ENODEV; 235 236 ret = pci_register_driver(&hyperv_pci_driver); 237 if (ret != 0) 238 return ret; 239 240 return vmbus_driver_register(&hyperv_hv_driver); 241 } 242 243 static void __exit hyperv_exit(void) 244 { 245 vmbus_driver_unregister(&hyperv_hv_driver); 246 pci_unregister_driver(&hyperv_pci_driver); 247 } 248 249 module_init(hyperv_init); 250 module_exit(hyperv_exit); 251 252 MODULE_DEVICE_TABLE(pci, hyperv_pci_tbl); 253 MODULE_DEVICE_TABLE(vmbus, hyperv_vmbus_tbl); 254 MODULE_LICENSE("GPL"); 255 MODULE_AUTHOR("Deepak Rawat <drawat.floss@gmail.com>"); 256 MODULE_DESCRIPTION("DRM driver for Hyper-V synthetic video device"); 257