1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2020-21 Intel Corporation. 4 */ 5 6 #include <linux/acpi.h> 7 #include <linux/bitfield.h> 8 #include <linux/module.h> 9 #include <net/rtnetlink.h> 10 11 #include "iosm_ipc_imem.h" 12 #include "iosm_ipc_pcie.h" 13 #include "iosm_ipc_protocol.h" 14 15 MODULE_DESCRIPTION("IOSM Driver"); 16 MODULE_LICENSE("GPL v2"); 17 18 /* WWAN GUID */ 19 static guid_t wwan_acpi_guid = GUID_INIT(0xbad01b75, 0x22a8, 0x4f48, 0x87, 0x92, 20 0xbd, 0xde, 0x94, 0x67, 0x74, 0x7d); 21 22 static void ipc_pcie_resources_release(struct iosm_pcie *ipc_pcie) 23 { 24 /* Free the MSI resources. */ 25 ipc_release_irq(ipc_pcie); 26 27 /* Free mapped doorbell scratchpad bus memory into CPU space. */ 28 iounmap(ipc_pcie->scratchpad); 29 30 /* Free mapped IPC_REGS bus memory into CPU space. */ 31 iounmap(ipc_pcie->ipc_regs); 32 33 /* Releases all PCI I/O and memory resources previously reserved by a 34 * successful call to pci_request_regions. Call this function only 35 * after all use of the PCI regions has ceased. 36 */ 37 pci_release_regions(ipc_pcie->pci); 38 } 39 40 static void ipc_pcie_cleanup(struct iosm_pcie *ipc_pcie) 41 { 42 /* Free the shared memory resources. */ 43 ipc_imem_cleanup(ipc_pcie->imem); 44 45 ipc_pcie_resources_release(ipc_pcie); 46 47 /* Signal to the system that the PCI device is not in use. */ 48 pci_disable_device(ipc_pcie->pci); 49 } 50 51 static void ipc_pcie_deinit(struct iosm_pcie *ipc_pcie) 52 { 53 kfree(ipc_pcie->imem); 54 kfree(ipc_pcie); 55 } 56 57 static void ipc_pcie_remove(struct pci_dev *pci) 58 { 59 struct iosm_pcie *ipc_pcie = pci_get_drvdata(pci); 60 61 ipc_pcie_cleanup(ipc_pcie); 62 63 ipc_pcie_deinit(ipc_pcie); 64 } 65 66 static int ipc_pcie_resources_request(struct iosm_pcie *ipc_pcie) 67 { 68 struct pci_dev *pci = ipc_pcie->pci; 69 u32 cap = 0; 70 u32 ret; 71 72 /* Reserved PCI I/O and memory resources. 73 * Mark all PCI regions associated with PCI device pci as 74 * being reserved by owner IOSM_IPC. 75 */ 76 ret = pci_request_regions(pci, "IOSM_IPC"); 77 if (ret) { 78 dev_err(ipc_pcie->dev, "failed pci request regions"); 79 goto pci_request_region_fail; 80 } 81 82 /* Reserve the doorbell IPC REGS memory resources. 83 * Remap the memory into CPU space. Arrange for the physical address 84 * (BAR) to be visible from this driver. 85 * pci_ioremap_bar() ensures that the memory is marked uncachable. 86 */ 87 ipc_pcie->ipc_regs = pci_ioremap_bar(pci, ipc_pcie->ipc_regs_bar_nr); 88 89 if (!ipc_pcie->ipc_regs) { 90 dev_err(ipc_pcie->dev, "IPC REGS ioremap error"); 91 ret = -EBUSY; 92 goto ipc_regs_remap_fail; 93 } 94 95 /* Reserve the MMIO scratchpad memory resources. 96 * Remap the memory into CPU space. Arrange for the physical address 97 * (BAR) to be visible from this driver. 98 * pci_ioremap_bar() ensures that the memory is marked uncachable. 99 */ 100 ipc_pcie->scratchpad = 101 pci_ioremap_bar(pci, ipc_pcie->scratchpad_bar_nr); 102 103 if (!ipc_pcie->scratchpad) { 104 dev_err(ipc_pcie->dev, "doorbell scratchpad ioremap error"); 105 ret = -EBUSY; 106 goto scratch_remap_fail; 107 } 108 109 /* Install the irq handler triggered by CP. */ 110 ret = ipc_acquire_irq(ipc_pcie); 111 if (ret) { 112 dev_err(ipc_pcie->dev, "acquiring MSI irq failed!"); 113 goto irq_acquire_fail; 114 } 115 116 /* Enable bus-mastering for the IOSM IPC device. */ 117 pci_set_master(pci); 118 119 /* Enable LTR if possible 120 * This is needed for L1.2! 121 */ 122 pcie_capability_read_dword(ipc_pcie->pci, PCI_EXP_DEVCAP2, &cap); 123 if (cap & PCI_EXP_DEVCAP2_LTR) 124 pcie_capability_set_word(ipc_pcie->pci, PCI_EXP_DEVCTL2, 125 PCI_EXP_DEVCTL2_LTR_EN); 126 127 dev_dbg(ipc_pcie->dev, "link between AP and CP is fully on"); 128 129 return ret; 130 131 irq_acquire_fail: 132 iounmap(ipc_pcie->scratchpad); 133 scratch_remap_fail: 134 iounmap(ipc_pcie->ipc_regs); 135 ipc_regs_remap_fail: 136 pci_release_regions(pci); 137 pci_request_region_fail: 138 return ret; 139 } 140 141 bool ipc_pcie_check_aspm_enabled(struct iosm_pcie *ipc_pcie, 142 bool parent) 143 { 144 struct pci_dev *pdev; 145 u16 value = 0; 146 u32 enabled; 147 148 if (parent) 149 pdev = ipc_pcie->pci->bus->self; 150 else 151 pdev = ipc_pcie->pci; 152 153 pcie_capability_read_word(pdev, PCI_EXP_LNKCTL, &value); 154 enabled = value & PCI_EXP_LNKCTL_ASPMC; 155 dev_dbg(ipc_pcie->dev, "ASPM L1: 0x%04X 0x%03X", pdev->device, value); 156 157 return (enabled == PCI_EXP_LNKCTL_ASPM_L1 || 158 enabled == PCI_EXP_LNKCTL_ASPMC); 159 } 160 161 bool ipc_pcie_check_data_link_active(struct iosm_pcie *ipc_pcie) 162 { 163 struct pci_dev *parent; 164 u16 link_status = 0; 165 166 if (!ipc_pcie->pci->bus || !ipc_pcie->pci->bus->self) { 167 dev_err(ipc_pcie->dev, "root port not found"); 168 return false; 169 } 170 171 parent = ipc_pcie->pci->bus->self; 172 173 pcie_capability_read_word(parent, PCI_EXP_LNKSTA, &link_status); 174 dev_dbg(ipc_pcie->dev, "Link status: 0x%04X", link_status); 175 176 return link_status & PCI_EXP_LNKSTA_DLLLA; 177 } 178 179 static bool ipc_pcie_check_aspm_supported(struct iosm_pcie *ipc_pcie, 180 bool parent) 181 { 182 struct pci_dev *pdev; 183 u32 support; 184 u32 cap = 0; 185 186 if (parent) 187 pdev = ipc_pcie->pci->bus->self; 188 else 189 pdev = ipc_pcie->pci; 190 pcie_capability_read_dword(pdev, PCI_EXP_LNKCAP, &cap); 191 support = u32_get_bits(cap, PCI_EXP_LNKCAP_ASPMS); 192 if (support < PCI_EXP_LNKCTL_ASPM_L1) { 193 dev_dbg(ipc_pcie->dev, "ASPM L1 not supported: 0x%04X", 194 pdev->device); 195 return false; 196 } 197 return true; 198 } 199 200 void ipc_pcie_config_aspm(struct iosm_pcie *ipc_pcie) 201 { 202 bool parent_aspm_enabled, dev_aspm_enabled; 203 204 /* check if both root port and child supports ASPM L1 */ 205 if (!ipc_pcie_check_aspm_supported(ipc_pcie, true) || 206 !ipc_pcie_check_aspm_supported(ipc_pcie, false)) 207 return; 208 209 parent_aspm_enabled = ipc_pcie_check_aspm_enabled(ipc_pcie, true); 210 dev_aspm_enabled = ipc_pcie_check_aspm_enabled(ipc_pcie, false); 211 212 dev_dbg(ipc_pcie->dev, "ASPM parent: %s device: %s", 213 parent_aspm_enabled ? "Enabled" : "Disabled", 214 dev_aspm_enabled ? "Enabled" : "Disabled"); 215 } 216 217 /* Initializes PCIe endpoint configuration */ 218 static void ipc_pcie_config_init(struct iosm_pcie *ipc_pcie) 219 { 220 /* BAR0 is used for doorbell */ 221 ipc_pcie->ipc_regs_bar_nr = IPC_DOORBELL_BAR0; 222 223 /* update HW configuration */ 224 ipc_pcie->scratchpad_bar_nr = IPC_SCRATCHPAD_BAR2; 225 ipc_pcie->doorbell_reg_offset = IPC_DOORBELL_CH_OFFSET; 226 ipc_pcie->doorbell_write = IPC_WRITE_PTR_REG_0; 227 ipc_pcie->doorbell_capture = IPC_CAPTURE_PTR_REG_0; 228 } 229 230 /* This will read the BIOS WWAN RTD3 settings: 231 * D0L1.2/D3L2/Disabled 232 */ 233 static enum ipc_pcie_sleep_state ipc_pcie_read_bios_cfg(struct device *dev) 234 { 235 union acpi_object *object; 236 acpi_handle handle_acpi; 237 238 handle_acpi = ACPI_HANDLE(dev); 239 if (!handle_acpi) { 240 pr_debug("pci device is NOT ACPI supporting device\n"); 241 goto default_ret; 242 } 243 244 object = acpi_evaluate_dsm(handle_acpi, &wwan_acpi_guid, 0, 3, NULL); 245 246 if (object && object->integer.value == 3) 247 return IPC_PCIE_D3L2; 248 249 default_ret: 250 return IPC_PCIE_D0L12; 251 } 252 253 static int ipc_pcie_probe(struct pci_dev *pci, 254 const struct pci_device_id *pci_id) 255 { 256 struct iosm_pcie *ipc_pcie = kzalloc(sizeof(*ipc_pcie), GFP_KERNEL); 257 258 pr_debug("Probing device 0x%X from the vendor 0x%X", pci_id->device, 259 pci_id->vendor); 260 261 if (!ipc_pcie) 262 goto ret_fail; 263 264 /* Initialize ipc dbg component for the PCIe device */ 265 ipc_pcie->dev = &pci->dev; 266 267 /* Set the driver specific data. */ 268 pci_set_drvdata(pci, ipc_pcie); 269 270 /* Save the address of the PCI device configuration. */ 271 ipc_pcie->pci = pci; 272 273 /* Update platform configuration */ 274 ipc_pcie_config_init(ipc_pcie); 275 276 /* Initialize the device before it is used. Ask low-level code 277 * to enable I/O and memory. Wake up the device if it was suspended. 278 */ 279 if (pci_enable_device(pci)) { 280 dev_err(ipc_pcie->dev, "failed to enable the AP PCIe device"); 281 /* If enable of PCIe device has failed then calling 282 * ipc_pcie_cleanup will panic the system. More over 283 * ipc_pcie_cleanup() is required to be called after 284 * ipc_imem_mount() 285 */ 286 goto pci_enable_fail; 287 } 288 289 ipc_pcie_config_aspm(ipc_pcie); 290 dev_dbg(ipc_pcie->dev, "PCIe device enabled."); 291 292 /* Read WWAN RTD3 BIOS Setting 293 */ 294 ipc_pcie->d3l2_support = ipc_pcie_read_bios_cfg(&pci->dev); 295 296 ipc_pcie->suspend = 0; 297 298 if (ipc_pcie_resources_request(ipc_pcie)) 299 goto resources_req_fail; 300 301 /* Establish the link to the imem layer. */ 302 ipc_pcie->imem = ipc_imem_init(ipc_pcie, pci->device, 303 ipc_pcie->scratchpad, ipc_pcie->dev); 304 if (!ipc_pcie->imem) { 305 dev_err(ipc_pcie->dev, "failed to init imem"); 306 goto imem_init_fail; 307 } 308 309 return 0; 310 311 imem_init_fail: 312 ipc_pcie_resources_release(ipc_pcie); 313 resources_req_fail: 314 pci_disable_device(pci); 315 pci_enable_fail: 316 kfree(ipc_pcie); 317 ret_fail: 318 return -EIO; 319 } 320 321 static const struct pci_device_id iosm_ipc_ids[] = { 322 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, INTEL_CP_DEVICE_7560_ID) }, 323 {} 324 }; 325 MODULE_DEVICE_TABLE(pci, iosm_ipc_ids); 326 327 /* Enter sleep in s2idle case 328 */ 329 static int __maybe_unused ipc_pcie_suspend_s2idle(struct iosm_pcie *ipc_pcie) 330 { 331 ipc_cp_irq_sleep_control(ipc_pcie, IPC_MEM_DEV_PM_FORCE_SLEEP); 332 333 /* Complete all memory stores before setting bit */ 334 smp_mb__before_atomic(); 335 336 set_bit(0, &ipc_pcie->suspend); 337 338 /* Complete all memory stores after setting bit */ 339 smp_mb__after_atomic(); 340 341 ipc_imem_pm_s2idle_sleep(ipc_pcie->imem, true); 342 343 return 0; 344 } 345 346 /* Resume from sleep in s2idle case 347 */ 348 static int __maybe_unused ipc_pcie_resume_s2idle(struct iosm_pcie *ipc_pcie) 349 { 350 ipc_cp_irq_sleep_control(ipc_pcie, IPC_MEM_DEV_PM_FORCE_ACTIVE); 351 352 ipc_imem_pm_s2idle_sleep(ipc_pcie->imem, false); 353 354 /* Complete all memory stores before clearing bit. */ 355 smp_mb__before_atomic(); 356 357 clear_bit(0, &ipc_pcie->suspend); 358 359 /* Complete all memory stores after clearing bit. */ 360 smp_mb__after_atomic(); 361 return 0; 362 } 363 364 int __maybe_unused ipc_pcie_suspend(struct iosm_pcie *ipc_pcie) 365 { 366 struct pci_dev *pdev; 367 int ret; 368 369 pdev = ipc_pcie->pci; 370 371 /* Execute D3 one time. */ 372 if (pdev->current_state != PCI_D0) { 373 dev_dbg(ipc_pcie->dev, "done for PM=%d", pdev->current_state); 374 return 0; 375 } 376 377 /* The HAL shall ask the shared memory layer whether D3 is allowed. */ 378 ipc_imem_pm_suspend(ipc_pcie->imem); 379 380 /* Save the PCI configuration space of a device before suspending. */ 381 ret = pci_save_state(pdev); 382 383 if (ret) { 384 dev_err(ipc_pcie->dev, "pci_save_state error=%d", ret); 385 return ret; 386 } 387 388 /* Set the power state of a PCI device. 389 * Transition a device to a new power state, using the device's PCI PM 390 * registers. 391 */ 392 ret = pci_set_power_state(pdev, PCI_D3cold); 393 394 if (ret) { 395 dev_err(ipc_pcie->dev, "pci_set_power_state error=%d", ret); 396 return ret; 397 } 398 399 dev_dbg(ipc_pcie->dev, "SUSPEND done"); 400 return ret; 401 } 402 403 int __maybe_unused ipc_pcie_resume(struct iosm_pcie *ipc_pcie) 404 { 405 int ret; 406 407 /* Set the power state of a PCI device. 408 * Transition a device to a new power state, using the device's PCI PM 409 * registers. 410 */ 411 ret = pci_set_power_state(ipc_pcie->pci, PCI_D0); 412 413 if (ret) { 414 dev_err(ipc_pcie->dev, "pci_set_power_state error=%d", ret); 415 return ret; 416 } 417 418 pci_restore_state(ipc_pcie->pci); 419 420 /* The HAL shall inform the shared memory layer that the device is 421 * active. 422 */ 423 ipc_imem_pm_resume(ipc_pcie->imem); 424 425 dev_dbg(ipc_pcie->dev, "RESUME done"); 426 return ret; 427 } 428 429 static int __maybe_unused ipc_pcie_suspend_cb(struct device *dev) 430 { 431 struct iosm_pcie *ipc_pcie; 432 struct pci_dev *pdev; 433 434 pdev = to_pci_dev(dev); 435 436 ipc_pcie = pci_get_drvdata(pdev); 437 438 switch (ipc_pcie->d3l2_support) { 439 case IPC_PCIE_D0L12: 440 ipc_pcie_suspend_s2idle(ipc_pcie); 441 break; 442 case IPC_PCIE_D3L2: 443 ipc_pcie_suspend(ipc_pcie); 444 break; 445 } 446 447 return 0; 448 } 449 450 static int __maybe_unused ipc_pcie_resume_cb(struct device *dev) 451 { 452 struct iosm_pcie *ipc_pcie; 453 struct pci_dev *pdev; 454 455 pdev = to_pci_dev(dev); 456 457 ipc_pcie = pci_get_drvdata(pdev); 458 459 switch (ipc_pcie->d3l2_support) { 460 case IPC_PCIE_D0L12: 461 ipc_pcie_resume_s2idle(ipc_pcie); 462 break; 463 case IPC_PCIE_D3L2: 464 ipc_pcie_resume(ipc_pcie); 465 break; 466 } 467 468 return 0; 469 } 470 471 static SIMPLE_DEV_PM_OPS(iosm_ipc_pm, ipc_pcie_suspend_cb, ipc_pcie_resume_cb); 472 473 static struct pci_driver iosm_ipc_driver = { 474 .name = KBUILD_MODNAME, 475 .probe = ipc_pcie_probe, 476 .remove = ipc_pcie_remove, 477 .driver = { 478 .pm = &iosm_ipc_pm, 479 }, 480 .id_table = iosm_ipc_ids, 481 }; 482 483 int ipc_pcie_addr_map(struct iosm_pcie *ipc_pcie, unsigned char *data, 484 size_t size, dma_addr_t *mapping, int direction) 485 { 486 if (ipc_pcie->pci) { 487 *mapping = dma_map_single(&ipc_pcie->pci->dev, data, size, 488 direction); 489 if (dma_mapping_error(&ipc_pcie->pci->dev, *mapping)) { 490 dev_err(ipc_pcie->dev, "dma mapping failed"); 491 return -EINVAL; 492 } 493 } 494 return 0; 495 } 496 497 void ipc_pcie_addr_unmap(struct iosm_pcie *ipc_pcie, size_t size, 498 dma_addr_t mapping, int direction) 499 { 500 if (!mapping) 501 return; 502 if (ipc_pcie->pci) 503 dma_unmap_single(&ipc_pcie->pci->dev, mapping, size, direction); 504 } 505 506 struct sk_buff *ipc_pcie_alloc_local_skb(struct iosm_pcie *ipc_pcie, 507 gfp_t flags, size_t size) 508 { 509 struct sk_buff *skb; 510 511 if (!ipc_pcie || !size) { 512 pr_err("invalid pcie object or size"); 513 return NULL; 514 } 515 516 skb = __netdev_alloc_skb(NULL, size, flags); 517 if (!skb) 518 return NULL; 519 520 IPC_CB(skb)->op_type = (u8)UL_DEFAULT; 521 IPC_CB(skb)->mapping = 0; 522 523 return skb; 524 } 525 526 struct sk_buff *ipc_pcie_alloc_skb(struct iosm_pcie *ipc_pcie, size_t size, 527 gfp_t flags, dma_addr_t *mapping, 528 int direction, size_t headroom) 529 { 530 struct sk_buff *skb = ipc_pcie_alloc_local_skb(ipc_pcie, flags, 531 size + headroom); 532 if (!skb) 533 return NULL; 534 535 if (headroom) 536 skb_reserve(skb, headroom); 537 538 if (ipc_pcie_addr_map(ipc_pcie, skb->data, size, mapping, direction)) { 539 dev_kfree_skb(skb); 540 return NULL; 541 } 542 543 BUILD_BUG_ON(sizeof(*IPC_CB(skb)) > sizeof(skb->cb)); 544 545 /* Store the mapping address in skb scratch pad for later usage */ 546 IPC_CB(skb)->mapping = *mapping; 547 IPC_CB(skb)->direction = direction; 548 IPC_CB(skb)->len = size; 549 550 return skb; 551 } 552 553 void ipc_pcie_kfree_skb(struct iosm_pcie *ipc_pcie, struct sk_buff *skb) 554 { 555 if (!skb) 556 return; 557 558 ipc_pcie_addr_unmap(ipc_pcie, IPC_CB(skb)->len, IPC_CB(skb)->mapping, 559 IPC_CB(skb)->direction); 560 IPC_CB(skb)->mapping = 0; 561 dev_kfree_skb(skb); 562 } 563 564 static int __init iosm_ipc_driver_init(void) 565 { 566 if (pci_register_driver(&iosm_ipc_driver)) { 567 pr_err("registering of IOSM PCIe driver failed"); 568 return -1; 569 } 570 571 return 0; 572 } 573 574 static void __exit iosm_ipc_driver_exit(void) 575 { 576 pci_unregister_driver(&iosm_ipc_driver); 577 } 578 579 module_init(iosm_ipc_driver_init); 580 module_exit(iosm_ipc_driver_exit); 581