1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * PCI EPF driver for MHI Endpoint devices 4 * 5 * Copyright (C) 2023 Linaro Ltd. 6 * Author: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> 7 */ 8 9 #include <linux/dmaengine.h> 10 #include <linux/mhi_ep.h> 11 #include <linux/module.h> 12 #include <linux/of_dma.h> 13 #include <linux/platform_device.h> 14 #include <linux/pci-epc.h> 15 #include <linux/pci-epf.h> 16 17 #define MHI_VERSION_1_0 0x01000000 18 19 #define to_epf_mhi(cntrl) container_of(cntrl, struct pci_epf_mhi, cntrl) 20 21 /* Platform specific flags */ 22 #define MHI_EPF_USE_DMA BIT(0) 23 24 struct pci_epf_mhi_ep_info { 25 const struct mhi_ep_cntrl_config *config; 26 struct pci_epf_header *epf_header; 27 enum pci_barno bar_num; 28 u32 epf_flags; 29 u32 msi_count; 30 u32 mru; 31 u32 flags; 32 }; 33 34 #define MHI_EP_CHANNEL_CONFIG(ch_num, ch_name, direction) \ 35 { \ 36 .num = ch_num, \ 37 .name = ch_name, \ 38 .dir = direction, \ 39 } 40 41 #define MHI_EP_CHANNEL_CONFIG_UL(ch_num, ch_name) \ 42 MHI_EP_CHANNEL_CONFIG(ch_num, ch_name, DMA_TO_DEVICE) 43 44 #define MHI_EP_CHANNEL_CONFIG_DL(ch_num, ch_name) \ 45 MHI_EP_CHANNEL_CONFIG(ch_num, ch_name, DMA_FROM_DEVICE) 46 47 static const struct mhi_ep_channel_config mhi_v1_channels[] = { 48 MHI_EP_CHANNEL_CONFIG_UL(0, "LOOPBACK"), 49 MHI_EP_CHANNEL_CONFIG_DL(1, "LOOPBACK"), 50 MHI_EP_CHANNEL_CONFIG_UL(2, "SAHARA"), 51 MHI_EP_CHANNEL_CONFIG_DL(3, "SAHARA"), 52 MHI_EP_CHANNEL_CONFIG_UL(4, "DIAG"), 53 MHI_EP_CHANNEL_CONFIG_DL(5, "DIAG"), 54 MHI_EP_CHANNEL_CONFIG_UL(6, "SSR"), 55 MHI_EP_CHANNEL_CONFIG_DL(7, "SSR"), 56 MHI_EP_CHANNEL_CONFIG_UL(8, "QDSS"), 57 MHI_EP_CHANNEL_CONFIG_DL(9, "QDSS"), 58 MHI_EP_CHANNEL_CONFIG_UL(10, "EFS"), 59 MHI_EP_CHANNEL_CONFIG_DL(11, "EFS"), 60 MHI_EP_CHANNEL_CONFIG_UL(12, "MBIM"), 61 MHI_EP_CHANNEL_CONFIG_DL(13, "MBIM"), 62 MHI_EP_CHANNEL_CONFIG_UL(14, "QMI"), 63 MHI_EP_CHANNEL_CONFIG_DL(15, "QMI"), 64 MHI_EP_CHANNEL_CONFIG_UL(16, "QMI"), 65 MHI_EP_CHANNEL_CONFIG_DL(17, "QMI"), 66 MHI_EP_CHANNEL_CONFIG_UL(18, "IP-CTRL-1"), 67 MHI_EP_CHANNEL_CONFIG_DL(19, "IP-CTRL-1"), 68 MHI_EP_CHANNEL_CONFIG_UL(20, "IPCR"), 69 MHI_EP_CHANNEL_CONFIG_DL(21, "IPCR"), 70 MHI_EP_CHANNEL_CONFIG_UL(32, "DUN"), 71 MHI_EP_CHANNEL_CONFIG_DL(33, "DUN"), 72 MHI_EP_CHANNEL_CONFIG_UL(46, "IP_SW0"), 73 MHI_EP_CHANNEL_CONFIG_DL(47, "IP_SW0"), 74 }; 75 76 static const struct mhi_ep_cntrl_config mhi_v1_config = { 77 .max_channels = 128, 78 .num_channels = ARRAY_SIZE(mhi_v1_channels), 79 .ch_cfg = mhi_v1_channels, 80 .mhi_version = MHI_VERSION_1_0, 81 }; 82 83 static struct pci_epf_header sdx55_header = { 84 .vendorid = PCI_VENDOR_ID_QCOM, 85 .deviceid = 0x0306, 86 .baseclass_code = PCI_BASE_CLASS_COMMUNICATION, 87 .subclass_code = PCI_CLASS_COMMUNICATION_MODEM & 0xff, 88 .interrupt_pin = PCI_INTERRUPT_INTA, 89 }; 90 91 static const struct pci_epf_mhi_ep_info sdx55_info = { 92 .config = &mhi_v1_config, 93 .epf_header = &sdx55_header, 94 .bar_num = BAR_0, 95 .epf_flags = PCI_BASE_ADDRESS_MEM_TYPE_32, 96 .msi_count = 32, 97 .mru = 0x8000, 98 }; 99 100 static struct pci_epf_header sm8450_header = { 101 .vendorid = PCI_VENDOR_ID_QCOM, 102 .deviceid = 0x0306, 103 .baseclass_code = PCI_CLASS_OTHERS, 104 .interrupt_pin = PCI_INTERRUPT_INTA, 105 }; 106 107 static const struct pci_epf_mhi_ep_info sm8450_info = { 108 .config = &mhi_v1_config, 109 .epf_header = &sm8450_header, 110 .bar_num = BAR_0, 111 .epf_flags = PCI_BASE_ADDRESS_MEM_TYPE_32, 112 .msi_count = 32, 113 .mru = 0x8000, 114 .flags = MHI_EPF_USE_DMA, 115 }; 116 117 struct pci_epf_mhi { 118 const struct pci_epc_features *epc_features; 119 const struct pci_epf_mhi_ep_info *info; 120 struct mhi_ep_cntrl mhi_cntrl; 121 struct pci_epf *epf; 122 struct mutex lock; 123 void __iomem *mmio; 124 resource_size_t mmio_phys; 125 struct dma_chan *dma_chan_tx; 126 struct dma_chan *dma_chan_rx; 127 u32 mmio_size; 128 int irq; 129 }; 130 131 static size_t get_align_offset(struct pci_epf_mhi *epf_mhi, u64 addr) 132 { 133 return addr & (epf_mhi->epc_features->align -1); 134 } 135 136 static int __pci_epf_mhi_alloc_map(struct mhi_ep_cntrl *mhi_cntrl, u64 pci_addr, 137 phys_addr_t *paddr, void __iomem **vaddr, 138 size_t offset, size_t size) 139 { 140 struct pci_epf_mhi *epf_mhi = to_epf_mhi(mhi_cntrl); 141 struct pci_epf *epf = epf_mhi->epf; 142 struct pci_epc *epc = epf->epc; 143 int ret; 144 145 *vaddr = pci_epc_mem_alloc_addr(epc, paddr, size + offset); 146 if (!*vaddr) 147 return -ENOMEM; 148 149 ret = pci_epc_map_addr(epc, epf->func_no, epf->vfunc_no, *paddr, 150 pci_addr - offset, size + offset); 151 if (ret) { 152 pci_epc_mem_free_addr(epc, *paddr, *vaddr, size + offset); 153 return ret; 154 } 155 156 *paddr = *paddr + offset; 157 *vaddr = *vaddr + offset; 158 159 return 0; 160 } 161 162 static int pci_epf_mhi_alloc_map(struct mhi_ep_cntrl *mhi_cntrl, u64 pci_addr, 163 phys_addr_t *paddr, void __iomem **vaddr, 164 size_t size) 165 { 166 struct pci_epf_mhi *epf_mhi = to_epf_mhi(mhi_cntrl); 167 size_t offset = get_align_offset(epf_mhi, pci_addr); 168 169 return __pci_epf_mhi_alloc_map(mhi_cntrl, pci_addr, paddr, vaddr, 170 offset, size); 171 } 172 173 static void __pci_epf_mhi_unmap_free(struct mhi_ep_cntrl *mhi_cntrl, 174 u64 pci_addr, phys_addr_t paddr, 175 void __iomem *vaddr, size_t offset, 176 size_t size) 177 { 178 struct pci_epf_mhi *epf_mhi = to_epf_mhi(mhi_cntrl); 179 struct pci_epf *epf = epf_mhi->epf; 180 struct pci_epc *epc = epf->epc; 181 182 pci_epc_unmap_addr(epc, epf->func_no, epf->vfunc_no, paddr - offset); 183 pci_epc_mem_free_addr(epc, paddr - offset, vaddr - offset, 184 size + offset); 185 } 186 187 static void pci_epf_mhi_unmap_free(struct mhi_ep_cntrl *mhi_cntrl, u64 pci_addr, 188 phys_addr_t paddr, void __iomem *vaddr, 189 size_t size) 190 { 191 struct pci_epf_mhi *epf_mhi = to_epf_mhi(mhi_cntrl); 192 size_t offset = get_align_offset(epf_mhi, pci_addr); 193 194 __pci_epf_mhi_unmap_free(mhi_cntrl, pci_addr, paddr, vaddr, offset, 195 size); 196 } 197 198 static void pci_epf_mhi_raise_irq(struct mhi_ep_cntrl *mhi_cntrl, u32 vector) 199 { 200 struct pci_epf_mhi *epf_mhi = to_epf_mhi(mhi_cntrl); 201 struct pci_epf *epf = epf_mhi->epf; 202 struct pci_epc *epc = epf->epc; 203 204 /* 205 * MHI supplies 0 based MSI vectors but the API expects the vector 206 * number to start from 1, so we need to increment the vector by 1. 207 */ 208 pci_epc_raise_irq(epc, epf->func_no, epf->vfunc_no, PCI_EPC_IRQ_MSI, 209 vector + 1); 210 } 211 212 static int pci_epf_mhi_iatu_read(struct mhi_ep_cntrl *mhi_cntrl, 213 struct mhi_ep_buf_info *buf_info) 214 { 215 struct pci_epf_mhi *epf_mhi = to_epf_mhi(mhi_cntrl); 216 size_t offset = get_align_offset(epf_mhi, buf_info->host_addr); 217 void __iomem *tre_buf; 218 phys_addr_t tre_phys; 219 int ret; 220 221 mutex_lock(&epf_mhi->lock); 222 223 ret = __pci_epf_mhi_alloc_map(mhi_cntrl, buf_info->host_addr, &tre_phys, 224 &tre_buf, offset, buf_info->size); 225 if (ret) { 226 mutex_unlock(&epf_mhi->lock); 227 return ret; 228 } 229 230 memcpy_fromio(buf_info->dev_addr, tre_buf, buf_info->size); 231 232 __pci_epf_mhi_unmap_free(mhi_cntrl, buf_info->host_addr, tre_phys, 233 tre_buf, offset, buf_info->size); 234 235 mutex_unlock(&epf_mhi->lock); 236 237 return 0; 238 } 239 240 static int pci_epf_mhi_iatu_write(struct mhi_ep_cntrl *mhi_cntrl, 241 struct mhi_ep_buf_info *buf_info) 242 { 243 struct pci_epf_mhi *epf_mhi = to_epf_mhi(mhi_cntrl); 244 size_t offset = get_align_offset(epf_mhi, buf_info->host_addr); 245 void __iomem *tre_buf; 246 phys_addr_t tre_phys; 247 int ret; 248 249 mutex_lock(&epf_mhi->lock); 250 251 ret = __pci_epf_mhi_alloc_map(mhi_cntrl, buf_info->host_addr, &tre_phys, 252 &tre_buf, offset, buf_info->size); 253 if (ret) { 254 mutex_unlock(&epf_mhi->lock); 255 return ret; 256 } 257 258 memcpy_toio(tre_buf, buf_info->dev_addr, buf_info->size); 259 260 __pci_epf_mhi_unmap_free(mhi_cntrl, buf_info->host_addr, tre_phys, 261 tre_buf, offset, buf_info->size); 262 263 mutex_unlock(&epf_mhi->lock); 264 265 return 0; 266 } 267 268 static void pci_epf_mhi_dma_callback(void *param) 269 { 270 complete(param); 271 } 272 273 static int pci_epf_mhi_edma_read(struct mhi_ep_cntrl *mhi_cntrl, 274 struct mhi_ep_buf_info *buf_info) 275 { 276 struct pci_epf_mhi *epf_mhi = to_epf_mhi(mhi_cntrl); 277 struct device *dma_dev = epf_mhi->epf->epc->dev.parent; 278 struct dma_chan *chan = epf_mhi->dma_chan_rx; 279 struct device *dev = &epf_mhi->epf->dev; 280 DECLARE_COMPLETION_ONSTACK(complete); 281 struct dma_async_tx_descriptor *desc; 282 struct dma_slave_config config = {}; 283 dma_cookie_t cookie; 284 dma_addr_t dst_addr; 285 int ret; 286 287 if (buf_info->size < SZ_4K) 288 return pci_epf_mhi_iatu_read(mhi_cntrl, buf_info); 289 290 mutex_lock(&epf_mhi->lock); 291 292 config.direction = DMA_DEV_TO_MEM; 293 config.src_addr = buf_info->host_addr; 294 295 ret = dmaengine_slave_config(chan, &config); 296 if (ret) { 297 dev_err(dev, "Failed to configure DMA channel\n"); 298 goto err_unlock; 299 } 300 301 dst_addr = dma_map_single(dma_dev, buf_info->dev_addr, buf_info->size, 302 DMA_FROM_DEVICE); 303 ret = dma_mapping_error(dma_dev, dst_addr); 304 if (ret) { 305 dev_err(dev, "Failed to map remote memory\n"); 306 goto err_unlock; 307 } 308 309 desc = dmaengine_prep_slave_single(chan, dst_addr, buf_info->size, 310 DMA_DEV_TO_MEM, 311 DMA_CTRL_ACK | DMA_PREP_INTERRUPT); 312 if (!desc) { 313 dev_err(dev, "Failed to prepare DMA\n"); 314 ret = -EIO; 315 goto err_unmap; 316 } 317 318 desc->callback = pci_epf_mhi_dma_callback; 319 desc->callback_param = &complete; 320 321 cookie = dmaengine_submit(desc); 322 ret = dma_submit_error(cookie); 323 if (ret) { 324 dev_err(dev, "Failed to do DMA submit\n"); 325 goto err_unmap; 326 } 327 328 dma_async_issue_pending(chan); 329 ret = wait_for_completion_timeout(&complete, msecs_to_jiffies(1000)); 330 if (!ret) { 331 dev_err(dev, "DMA transfer timeout\n"); 332 dmaengine_terminate_sync(chan); 333 ret = -ETIMEDOUT; 334 } 335 336 err_unmap: 337 dma_unmap_single(dma_dev, dst_addr, buf_info->size, DMA_FROM_DEVICE); 338 err_unlock: 339 mutex_unlock(&epf_mhi->lock); 340 341 return ret; 342 } 343 344 static int pci_epf_mhi_edma_write(struct mhi_ep_cntrl *mhi_cntrl, 345 struct mhi_ep_buf_info *buf_info) 346 { 347 struct pci_epf_mhi *epf_mhi = to_epf_mhi(mhi_cntrl); 348 struct device *dma_dev = epf_mhi->epf->epc->dev.parent; 349 struct dma_chan *chan = epf_mhi->dma_chan_tx; 350 struct device *dev = &epf_mhi->epf->dev; 351 DECLARE_COMPLETION_ONSTACK(complete); 352 struct dma_async_tx_descriptor *desc; 353 struct dma_slave_config config = {}; 354 dma_cookie_t cookie; 355 dma_addr_t src_addr; 356 int ret; 357 358 if (buf_info->size < SZ_4K) 359 return pci_epf_mhi_iatu_write(mhi_cntrl, buf_info); 360 361 mutex_lock(&epf_mhi->lock); 362 363 config.direction = DMA_MEM_TO_DEV; 364 config.dst_addr = buf_info->host_addr; 365 366 ret = dmaengine_slave_config(chan, &config); 367 if (ret) { 368 dev_err(dev, "Failed to configure DMA channel\n"); 369 goto err_unlock; 370 } 371 372 src_addr = dma_map_single(dma_dev, buf_info->dev_addr, buf_info->size, 373 DMA_TO_DEVICE); 374 ret = dma_mapping_error(dma_dev, src_addr); 375 if (ret) { 376 dev_err(dev, "Failed to map remote memory\n"); 377 goto err_unlock; 378 } 379 380 desc = dmaengine_prep_slave_single(chan, src_addr, buf_info->size, 381 DMA_MEM_TO_DEV, 382 DMA_CTRL_ACK | DMA_PREP_INTERRUPT); 383 if (!desc) { 384 dev_err(dev, "Failed to prepare DMA\n"); 385 ret = -EIO; 386 goto err_unmap; 387 } 388 389 desc->callback = pci_epf_mhi_dma_callback; 390 desc->callback_param = &complete; 391 392 cookie = dmaengine_submit(desc); 393 ret = dma_submit_error(cookie); 394 if (ret) { 395 dev_err(dev, "Failed to do DMA submit\n"); 396 goto err_unmap; 397 } 398 399 dma_async_issue_pending(chan); 400 ret = wait_for_completion_timeout(&complete, msecs_to_jiffies(1000)); 401 if (!ret) { 402 dev_err(dev, "DMA transfer timeout\n"); 403 dmaengine_terminate_sync(chan); 404 ret = -ETIMEDOUT; 405 } 406 407 err_unmap: 408 dma_unmap_single(dma_dev, src_addr, buf_info->size, DMA_TO_DEVICE); 409 err_unlock: 410 mutex_unlock(&epf_mhi->lock); 411 412 return ret; 413 } 414 415 struct epf_dma_filter { 416 struct device *dev; 417 u32 dma_mask; 418 }; 419 420 static bool pci_epf_mhi_filter(struct dma_chan *chan, void *node) 421 { 422 struct epf_dma_filter *filter = node; 423 struct dma_slave_caps caps; 424 425 memset(&caps, 0, sizeof(caps)); 426 dma_get_slave_caps(chan, &caps); 427 428 return chan->device->dev == filter->dev && filter->dma_mask & 429 caps.directions; 430 } 431 432 static int pci_epf_mhi_dma_init(struct pci_epf_mhi *epf_mhi) 433 { 434 struct device *dma_dev = epf_mhi->epf->epc->dev.parent; 435 struct device *dev = &epf_mhi->epf->dev; 436 struct epf_dma_filter filter; 437 dma_cap_mask_t mask; 438 439 dma_cap_zero(mask); 440 dma_cap_set(DMA_SLAVE, mask); 441 442 filter.dev = dma_dev; 443 filter.dma_mask = BIT(DMA_MEM_TO_DEV); 444 epf_mhi->dma_chan_tx = dma_request_channel(mask, pci_epf_mhi_filter, 445 &filter); 446 if (IS_ERR_OR_NULL(epf_mhi->dma_chan_tx)) { 447 dev_err(dev, "Failed to request tx channel\n"); 448 return -ENODEV; 449 } 450 451 filter.dma_mask = BIT(DMA_DEV_TO_MEM); 452 epf_mhi->dma_chan_rx = dma_request_channel(mask, pci_epf_mhi_filter, 453 &filter); 454 if (IS_ERR_OR_NULL(epf_mhi->dma_chan_rx)) { 455 dev_err(dev, "Failed to request rx channel\n"); 456 dma_release_channel(epf_mhi->dma_chan_tx); 457 epf_mhi->dma_chan_tx = NULL; 458 return -ENODEV; 459 } 460 461 return 0; 462 } 463 464 static void pci_epf_mhi_dma_deinit(struct pci_epf_mhi *epf_mhi) 465 { 466 dma_release_channel(epf_mhi->dma_chan_tx); 467 dma_release_channel(epf_mhi->dma_chan_rx); 468 epf_mhi->dma_chan_tx = NULL; 469 epf_mhi->dma_chan_rx = NULL; 470 } 471 472 static int pci_epf_mhi_core_init(struct pci_epf *epf) 473 { 474 struct pci_epf_mhi *epf_mhi = epf_get_drvdata(epf); 475 const struct pci_epf_mhi_ep_info *info = epf_mhi->info; 476 struct pci_epf_bar *epf_bar = &epf->bar[info->bar_num]; 477 struct pci_epc *epc = epf->epc; 478 struct device *dev = &epf->dev; 479 int ret; 480 481 epf_bar->phys_addr = epf_mhi->mmio_phys; 482 epf_bar->size = epf_mhi->mmio_size; 483 epf_bar->barno = info->bar_num; 484 epf_bar->flags = info->epf_flags; 485 ret = pci_epc_set_bar(epc, epf->func_no, epf->vfunc_no, epf_bar); 486 if (ret) { 487 dev_err(dev, "Failed to set BAR: %d\n", ret); 488 return ret; 489 } 490 491 ret = pci_epc_set_msi(epc, epf->func_no, epf->vfunc_no, 492 order_base_2(info->msi_count)); 493 if (ret) { 494 dev_err(dev, "Failed to set MSI configuration: %d\n", ret); 495 return ret; 496 } 497 498 ret = pci_epc_write_header(epc, epf->func_no, epf->vfunc_no, 499 epf->header); 500 if (ret) { 501 dev_err(dev, "Failed to set Configuration header: %d\n", ret); 502 return ret; 503 } 504 505 epf_mhi->epc_features = pci_epc_get_features(epc, epf->func_no, epf->vfunc_no); 506 if (!epf_mhi->epc_features) 507 return -ENODATA; 508 509 return 0; 510 } 511 512 static int pci_epf_mhi_link_up(struct pci_epf *epf) 513 { 514 struct pci_epf_mhi *epf_mhi = epf_get_drvdata(epf); 515 const struct pci_epf_mhi_ep_info *info = epf_mhi->info; 516 struct mhi_ep_cntrl *mhi_cntrl = &epf_mhi->mhi_cntrl; 517 struct pci_epc *epc = epf->epc; 518 struct device *dev = &epf->dev; 519 int ret; 520 521 if (info->flags & MHI_EPF_USE_DMA) { 522 ret = pci_epf_mhi_dma_init(epf_mhi); 523 if (ret) { 524 dev_err(dev, "Failed to initialize DMA: %d\n", ret); 525 return ret; 526 } 527 } 528 529 mhi_cntrl->mmio = epf_mhi->mmio; 530 mhi_cntrl->irq = epf_mhi->irq; 531 mhi_cntrl->mru = info->mru; 532 533 /* Assign the struct dev of PCI EP as MHI controller device */ 534 mhi_cntrl->cntrl_dev = epc->dev.parent; 535 mhi_cntrl->raise_irq = pci_epf_mhi_raise_irq; 536 mhi_cntrl->alloc_map = pci_epf_mhi_alloc_map; 537 mhi_cntrl->unmap_free = pci_epf_mhi_unmap_free; 538 if (info->flags & MHI_EPF_USE_DMA) { 539 mhi_cntrl->read_from_host = pci_epf_mhi_edma_read; 540 mhi_cntrl->write_to_host = pci_epf_mhi_edma_write; 541 } else { 542 mhi_cntrl->read_from_host = pci_epf_mhi_iatu_read; 543 mhi_cntrl->write_to_host = pci_epf_mhi_iatu_write; 544 } 545 546 /* Register the MHI EP controller */ 547 ret = mhi_ep_register_controller(mhi_cntrl, info->config); 548 if (ret) { 549 dev_err(dev, "Failed to register MHI EP controller: %d\n", ret); 550 if (info->flags & MHI_EPF_USE_DMA) 551 pci_epf_mhi_dma_deinit(epf_mhi); 552 return ret; 553 } 554 555 return 0; 556 } 557 558 static int pci_epf_mhi_link_down(struct pci_epf *epf) 559 { 560 struct pci_epf_mhi *epf_mhi = epf_get_drvdata(epf); 561 const struct pci_epf_mhi_ep_info *info = epf_mhi->info; 562 struct mhi_ep_cntrl *mhi_cntrl = &epf_mhi->mhi_cntrl; 563 564 if (mhi_cntrl->mhi_dev) { 565 mhi_ep_power_down(mhi_cntrl); 566 if (info->flags & MHI_EPF_USE_DMA) 567 pci_epf_mhi_dma_deinit(epf_mhi); 568 mhi_ep_unregister_controller(mhi_cntrl); 569 } 570 571 return 0; 572 } 573 574 static int pci_epf_mhi_bme(struct pci_epf *epf) 575 { 576 struct pci_epf_mhi *epf_mhi = epf_get_drvdata(epf); 577 const struct pci_epf_mhi_ep_info *info = epf_mhi->info; 578 struct mhi_ep_cntrl *mhi_cntrl = &epf_mhi->mhi_cntrl; 579 struct device *dev = &epf->dev; 580 int ret; 581 582 /* 583 * Power up the MHI EP stack if link is up and stack is in power down 584 * state. 585 */ 586 if (!mhi_cntrl->enabled && mhi_cntrl->mhi_dev) { 587 ret = mhi_ep_power_up(mhi_cntrl); 588 if (ret) { 589 dev_err(dev, "Failed to power up MHI EP: %d\n", ret); 590 if (info->flags & MHI_EPF_USE_DMA) 591 pci_epf_mhi_dma_deinit(epf_mhi); 592 mhi_ep_unregister_controller(mhi_cntrl); 593 } 594 } 595 596 return 0; 597 } 598 599 static int pci_epf_mhi_bind(struct pci_epf *epf) 600 { 601 struct pci_epf_mhi *epf_mhi = epf_get_drvdata(epf); 602 struct pci_epc *epc = epf->epc; 603 struct platform_device *pdev = to_platform_device(epc->dev.parent); 604 struct resource *res; 605 int ret; 606 607 /* Get MMIO base address from Endpoint controller */ 608 res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "mmio"); 609 epf_mhi->mmio_phys = res->start; 610 epf_mhi->mmio_size = resource_size(res); 611 612 epf_mhi->mmio = ioremap(epf_mhi->mmio_phys, epf_mhi->mmio_size); 613 if (!epf_mhi->mmio) 614 return -ENOMEM; 615 616 ret = platform_get_irq_byname(pdev, "doorbell"); 617 if (ret < 0) { 618 iounmap(epf_mhi->mmio); 619 return ret; 620 } 621 622 epf_mhi->irq = ret; 623 624 return 0; 625 } 626 627 static void pci_epf_mhi_unbind(struct pci_epf *epf) 628 { 629 struct pci_epf_mhi *epf_mhi = epf_get_drvdata(epf); 630 const struct pci_epf_mhi_ep_info *info = epf_mhi->info; 631 struct pci_epf_bar *epf_bar = &epf->bar[info->bar_num]; 632 struct mhi_ep_cntrl *mhi_cntrl = &epf_mhi->mhi_cntrl; 633 struct pci_epc *epc = epf->epc; 634 635 /* 636 * Forcefully power down the MHI EP stack. Only way to bring the MHI EP 637 * stack back to working state after successive bind is by getting BME 638 * from host. 639 */ 640 if (mhi_cntrl->mhi_dev) { 641 mhi_ep_power_down(mhi_cntrl); 642 if (info->flags & MHI_EPF_USE_DMA) 643 pci_epf_mhi_dma_deinit(epf_mhi); 644 mhi_ep_unregister_controller(mhi_cntrl); 645 } 646 647 iounmap(epf_mhi->mmio); 648 pci_epc_clear_bar(epc, epf->func_no, epf->vfunc_no, epf_bar); 649 } 650 651 static struct pci_epc_event_ops pci_epf_mhi_event_ops = { 652 .core_init = pci_epf_mhi_core_init, 653 .link_up = pci_epf_mhi_link_up, 654 .link_down = pci_epf_mhi_link_down, 655 .bme = pci_epf_mhi_bme, 656 }; 657 658 static int pci_epf_mhi_probe(struct pci_epf *epf, 659 const struct pci_epf_device_id *id) 660 { 661 struct pci_epf_mhi_ep_info *info = 662 (struct pci_epf_mhi_ep_info *)id->driver_data; 663 struct pci_epf_mhi *epf_mhi; 664 struct device *dev = &epf->dev; 665 666 epf_mhi = devm_kzalloc(dev, sizeof(*epf_mhi), GFP_KERNEL); 667 if (!epf_mhi) 668 return -ENOMEM; 669 670 epf->header = info->epf_header; 671 epf_mhi->info = info; 672 epf_mhi->epf = epf; 673 674 epf->event_ops = &pci_epf_mhi_event_ops; 675 676 mutex_init(&epf_mhi->lock); 677 678 epf_set_drvdata(epf, epf_mhi); 679 680 return 0; 681 } 682 683 static const struct pci_epf_device_id pci_epf_mhi_ids[] = { 684 { .name = "sdx55", .driver_data = (kernel_ulong_t)&sdx55_info }, 685 { .name = "sm8450", .driver_data = (kernel_ulong_t)&sm8450_info }, 686 {}, 687 }; 688 689 static struct pci_epf_ops pci_epf_mhi_ops = { 690 .unbind = pci_epf_mhi_unbind, 691 .bind = pci_epf_mhi_bind, 692 }; 693 694 static struct pci_epf_driver pci_epf_mhi_driver = { 695 .driver.name = "pci_epf_mhi", 696 .probe = pci_epf_mhi_probe, 697 .id_table = pci_epf_mhi_ids, 698 .ops = &pci_epf_mhi_ops, 699 .owner = THIS_MODULE, 700 }; 701 702 static int __init pci_epf_mhi_init(void) 703 { 704 return pci_epf_register_driver(&pci_epf_mhi_driver); 705 } 706 module_init(pci_epf_mhi_init); 707 708 static void __exit pci_epf_mhi_exit(void) 709 { 710 pci_epf_unregister_driver(&pci_epf_mhi_driver); 711 } 712 module_exit(pci_epf_mhi_exit); 713 714 MODULE_DESCRIPTION("PCI EPF driver for MHI Endpoint devices"); 715 MODULE_AUTHOR("Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>"); 716 MODULE_LICENSE("GPL"); 717