1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * ACPI support 4 * 5 * Copyright (C) 2020, Intel Corporation 6 * Author: Mika Westerberg <mika.westerberg@linux.intel.com> 7 */ 8 9 #include <linux/acpi.h> 10 #include <linux/pm_runtime.h> 11 12 #include "tb.h" 13 14 static acpi_status tb_acpi_add_link(acpi_handle handle, u32 level, void *data, 15 void **ret) 16 { 17 struct acpi_device *adev = acpi_fetch_acpi_dev(handle); 18 struct fwnode_handle *fwnode; 19 struct tb_nhi *nhi = data; 20 struct pci_dev *pdev; 21 struct device *dev; 22 23 if (!adev) 24 return AE_OK; 25 26 fwnode = fwnode_find_reference(acpi_fwnode_handle(adev), "usb4-host-interface", 0); 27 if (IS_ERR(fwnode)) 28 return AE_OK; 29 30 /* It needs to reference this NHI */ 31 if (dev_fwnode(&nhi->pdev->dev) != fwnode) 32 goto out_put; 33 34 /* 35 * Try to find physical device walking upwards to the hierarcy. 36 * We need to do this because the xHCI driver might not yet be 37 * bound so the USB3 SuperSpeed ports are not yet created. 38 */ 39 do { 40 dev = acpi_get_first_physical_node(adev); 41 if (dev) 42 break; 43 44 adev = acpi_dev_parent(adev); 45 } while (adev); 46 47 /* 48 * Check that the device is PCIe. This is because USB3 49 * SuperSpeed ports have this property and they are not power 50 * managed with the xHCI and the SuperSpeed hub so we create the 51 * link from xHCI instead. 52 */ 53 while (dev && !dev_is_pci(dev)) 54 dev = dev->parent; 55 56 if (!dev) 57 goto out_put; 58 59 /* 60 * Check that this actually matches the type of device we 61 * expect. It should either be xHCI or PCIe root/downstream 62 * port. 63 */ 64 pdev = to_pci_dev(dev); 65 if (pdev->class == PCI_CLASS_SERIAL_USB_XHCI || 66 (pci_is_pcie(pdev) && 67 (pci_pcie_type(pdev) == PCI_EXP_TYPE_ROOT_PORT || 68 pci_pcie_type(pdev) == PCI_EXP_TYPE_DOWNSTREAM))) { 69 const struct device_link *link; 70 71 /* 72 * Make them both active first to make sure the NHI does 73 * not runtime suspend before the consumer. The 74 * pm_runtime_put() below then allows the consumer to 75 * runtime suspend again (which then allows NHI runtime 76 * suspend too now that the device link is established). 77 */ 78 pm_runtime_get_sync(&pdev->dev); 79 80 link = device_link_add(&pdev->dev, &nhi->pdev->dev, 81 DL_FLAG_AUTOREMOVE_SUPPLIER | 82 DL_FLAG_RPM_ACTIVE | 83 DL_FLAG_PM_RUNTIME); 84 if (link) { 85 dev_dbg(&nhi->pdev->dev, "created link from %s\n", 86 dev_name(&pdev->dev)); 87 *(bool *)ret = true; 88 } else { 89 dev_warn(&nhi->pdev->dev, "device link creation from %s failed\n", 90 dev_name(&pdev->dev)); 91 } 92 93 pm_runtime_put(&pdev->dev); 94 } 95 96 out_put: 97 fwnode_handle_put(fwnode); 98 return AE_OK; 99 } 100 101 /** 102 * tb_acpi_add_links() - Add device links based on ACPI description 103 * @nhi: Pointer to NHI 104 * 105 * Goes over ACPI namespace finding tunneled ports that reference to 106 * @nhi ACPI node. For each reference a device link is added. The link 107 * is automatically removed by the driver core. 108 * 109 * Returns %true if at least one link was created. 110 */ 111 bool tb_acpi_add_links(struct tb_nhi *nhi) 112 { 113 acpi_status status; 114 bool ret = false; 115 116 if (!has_acpi_companion(&nhi->pdev->dev)) 117 return false; 118 119 /* 120 * Find all devices that have usb4-host-controller interface 121 * property that references to this NHI. 122 */ 123 status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT, 32, 124 tb_acpi_add_link, NULL, nhi, (void **)&ret); 125 if (ACPI_FAILURE(status)) { 126 dev_warn(&nhi->pdev->dev, "failed to enumerate tunneled ports\n"); 127 return false; 128 } 129 130 return ret; 131 } 132 133 /** 134 * tb_acpi_is_native() - Did the platform grant native TBT/USB4 control 135 * 136 * Returns %true if the platform granted OS native control over 137 * TBT/USB4. In this case software based connection manager can be used, 138 * otherwise there is firmware based connection manager running. 139 */ 140 bool tb_acpi_is_native(void) 141 { 142 return osc_sb_native_usb4_support_confirmed && 143 osc_sb_native_usb4_control; 144 } 145 146 /** 147 * tb_acpi_may_tunnel_usb3() - Is USB3 tunneling allowed by the platform 148 * 149 * When software based connection manager is used, this function 150 * returns %true if platform allows native USB3 tunneling. 151 */ 152 bool tb_acpi_may_tunnel_usb3(void) 153 { 154 if (tb_acpi_is_native()) 155 return osc_sb_native_usb4_control & OSC_USB_USB3_TUNNELING; 156 return true; 157 } 158 159 /** 160 * tb_acpi_may_tunnel_dp() - Is DisplayPort tunneling allowed by the platform 161 * 162 * When software based connection manager is used, this function 163 * returns %true if platform allows native DP tunneling. 164 */ 165 bool tb_acpi_may_tunnel_dp(void) 166 { 167 if (tb_acpi_is_native()) 168 return osc_sb_native_usb4_control & OSC_USB_DP_TUNNELING; 169 return true; 170 } 171 172 /** 173 * tb_acpi_may_tunnel_pcie() - Is PCIe tunneling allowed by the platform 174 * 175 * When software based connection manager is used, this function 176 * returns %true if platform allows native PCIe tunneling. 177 */ 178 bool tb_acpi_may_tunnel_pcie(void) 179 { 180 if (tb_acpi_is_native()) 181 return osc_sb_native_usb4_control & OSC_USB_PCIE_TUNNELING; 182 return true; 183 } 184 185 /** 186 * tb_acpi_is_xdomain_allowed() - Are XDomain connections allowed 187 * 188 * When software based connection manager is used, this function 189 * returns %true if platform allows XDomain connections. 190 */ 191 bool tb_acpi_is_xdomain_allowed(void) 192 { 193 if (tb_acpi_is_native()) 194 return osc_sb_native_usb4_control & OSC_USB_XDOMAIN; 195 return true; 196 } 197 198 /* UUID for retimer _DSM: e0053122-795b-4122-8a5e-57be1d26acb3 */ 199 static const guid_t retimer_dsm_guid = 200 GUID_INIT(0xe0053122, 0x795b, 0x4122, 201 0x8a, 0x5e, 0x57, 0xbe, 0x1d, 0x26, 0xac, 0xb3); 202 203 #define RETIMER_DSM_QUERY_ONLINE_STATE 1 204 #define RETIMER_DSM_SET_ONLINE_STATE 2 205 206 static int tb_acpi_retimer_set_power(struct tb_port *port, bool power) 207 { 208 struct usb4_port *usb4 = port->usb4; 209 union acpi_object argv4[2]; 210 struct acpi_device *adev; 211 union acpi_object *obj; 212 int ret; 213 214 if (!usb4->can_offline) 215 return 0; 216 217 adev = ACPI_COMPANION(&usb4->dev); 218 if (WARN_ON(!adev)) 219 return 0; 220 221 /* Check if we are already powered on (and in correct mode) */ 222 obj = acpi_evaluate_dsm_typed(adev->handle, &retimer_dsm_guid, 1, 223 RETIMER_DSM_QUERY_ONLINE_STATE, NULL, 224 ACPI_TYPE_INTEGER); 225 if (!obj) { 226 tb_port_warn(port, "ACPI: query online _DSM failed\n"); 227 return -EIO; 228 } 229 230 ret = obj->integer.value; 231 ACPI_FREE(obj); 232 233 if (power == ret) 234 return 0; 235 236 tb_port_dbg(port, "ACPI: calling _DSM to power %s retimers\n", 237 power ? "on" : "off"); 238 239 argv4[0].type = ACPI_TYPE_PACKAGE; 240 argv4[0].package.count = 1; 241 argv4[0].package.elements = &argv4[1]; 242 argv4[1].integer.type = ACPI_TYPE_INTEGER; 243 argv4[1].integer.value = power; 244 245 obj = acpi_evaluate_dsm_typed(adev->handle, &retimer_dsm_guid, 1, 246 RETIMER_DSM_SET_ONLINE_STATE, argv4, 247 ACPI_TYPE_INTEGER); 248 if (!obj) { 249 tb_port_warn(port, 250 "ACPI: set online state _DSM evaluation failed\n"); 251 return -EIO; 252 } 253 254 ret = obj->integer.value; 255 ACPI_FREE(obj); 256 257 if (ret >= 0) { 258 if (power) 259 return ret == 1 ? 0 : -EBUSY; 260 return 0; 261 } 262 263 tb_port_warn(port, "ACPI: set online state _DSM failed with error %d\n", ret); 264 return -EIO; 265 } 266 267 /** 268 * tb_acpi_power_on_retimers() - Call platform to power on retimers 269 * @port: USB4 port 270 * 271 * Calls platform to turn on power to all retimers behind this USB4 272 * port. After this function returns successfully the caller can 273 * continue with the normal retimer flows (as specified in the USB4 274 * spec). Note if this returns %-EBUSY it means the type-C port is in 275 * non-USB4/TBT mode (there is non-USB4/TBT device connected). 276 * 277 * This should only be called if the USB4/TBT link is not up. 278 * 279 * Returns %0 on success. 280 */ 281 int tb_acpi_power_on_retimers(struct tb_port *port) 282 { 283 return tb_acpi_retimer_set_power(port, true); 284 } 285 286 /** 287 * tb_acpi_power_off_retimers() - Call platform to power off retimers 288 * @port: USB4 port 289 * 290 * This is the opposite of tb_acpi_power_on_retimers(). After returning 291 * successfully the normal operations with the @port can continue. 292 * 293 * Returns %0 on success. 294 */ 295 int tb_acpi_power_off_retimers(struct tb_port *port) 296 { 297 return tb_acpi_retimer_set_power(port, false); 298 } 299 300 static bool tb_acpi_bus_match(struct device *dev) 301 { 302 return tb_is_switch(dev) || tb_is_usb4_port_device(dev); 303 } 304 305 static struct acpi_device *tb_acpi_switch_find_companion(struct tb_switch *sw) 306 { 307 struct tb_switch *parent_sw = tb_switch_parent(sw); 308 struct acpi_device *adev = NULL; 309 310 /* 311 * Device routers exists under the downstream facing USB4 port 312 * of the parent router. Their _ADR is always 0. 313 */ 314 if (parent_sw) { 315 struct tb_port *port = tb_switch_downstream_port(sw); 316 struct acpi_device *port_adev; 317 318 port_adev = acpi_find_child_by_adr(ACPI_COMPANION(&parent_sw->dev), 319 port->port); 320 if (port_adev) 321 adev = acpi_find_child_device(port_adev, 0, false); 322 } else { 323 struct tb_nhi *nhi = sw->tb->nhi; 324 struct acpi_device *parent_adev; 325 326 parent_adev = ACPI_COMPANION(&nhi->pdev->dev); 327 if (parent_adev) 328 adev = acpi_find_child_device(parent_adev, 0, false); 329 } 330 331 return adev; 332 } 333 334 static struct acpi_device *tb_acpi_find_companion(struct device *dev) 335 { 336 /* 337 * The Thunderbolt/USB4 hierarchy looks like following: 338 * 339 * Device (NHI) 340 * Device (HR) // Host router _ADR == 0 341 * Device (DFP0) // Downstream port _ADR == lane 0 adapter 342 * Device (DR) // Device router _ADR == 0 343 * Device (UFP) // Upstream port _ADR == lane 0 adapter 344 * Device (DFP1) // Downstream port _ADR == lane 0 adapter number 345 * 346 * At the moment we bind the host router to the corresponding 347 * Linux device. 348 */ 349 if (tb_is_switch(dev)) 350 return tb_acpi_switch_find_companion(tb_to_switch(dev)); 351 if (tb_is_usb4_port_device(dev)) 352 return acpi_find_child_by_adr(ACPI_COMPANION(dev->parent), 353 tb_to_usb4_port_device(dev)->port->port); 354 return NULL; 355 } 356 357 static void tb_acpi_setup(struct device *dev) 358 { 359 struct acpi_device *adev = ACPI_COMPANION(dev); 360 struct usb4_port *usb4 = tb_to_usb4_port_device(dev); 361 362 if (!adev || !usb4) 363 return; 364 365 if (acpi_check_dsm(adev->handle, &retimer_dsm_guid, 1, 366 BIT(RETIMER_DSM_QUERY_ONLINE_STATE) | 367 BIT(RETIMER_DSM_SET_ONLINE_STATE))) 368 usb4->can_offline = true; 369 } 370 371 static struct acpi_bus_type tb_acpi_bus = { 372 .name = "thunderbolt", 373 .match = tb_acpi_bus_match, 374 .find_companion = tb_acpi_find_companion, 375 .setup = tb_acpi_setup, 376 }; 377 378 int tb_acpi_init(void) 379 { 380 return register_acpi_bus_type(&tb_acpi_bus); 381 } 382 383 void tb_acpi_exit(void) 384 { 385 unregister_acpi_bus_type(&tb_acpi_bus); 386 } 387