1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Qualcomm Technologies HIDMA DMA engine low level code 4 * 5 * Copyright (c) 2015-2016, The Linux Foundation. All rights reserved. 6 */ 7 8 #include <linux/dmaengine.h> 9 #include <linux/slab.h> 10 #include <linux/interrupt.h> 11 #include <linux/mm.h> 12 #include <linux/highmem.h> 13 #include <linux/dma-mapping.h> 14 #include <linux/delay.h> 15 #include <linux/atomic.h> 16 #include <linux/iopoll.h> 17 #include <linux/kfifo.h> 18 #include <linux/bitops.h> 19 20 #include "hidma.h" 21 22 #define HIDMA_EVRE_SIZE 16 /* each EVRE is 16 bytes */ 23 24 #define HIDMA_TRCA_CTRLSTS_REG 0x000 25 #define HIDMA_TRCA_RING_LOW_REG 0x008 26 #define HIDMA_TRCA_RING_HIGH_REG 0x00C 27 #define HIDMA_TRCA_RING_LEN_REG 0x010 28 #define HIDMA_TRCA_DOORBELL_REG 0x400 29 30 #define HIDMA_EVCA_CTRLSTS_REG 0x000 31 #define HIDMA_EVCA_INTCTRL_REG 0x004 32 #define HIDMA_EVCA_RING_LOW_REG 0x008 33 #define HIDMA_EVCA_RING_HIGH_REG 0x00C 34 #define HIDMA_EVCA_RING_LEN_REG 0x010 35 #define HIDMA_EVCA_WRITE_PTR_REG 0x020 36 #define HIDMA_EVCA_DOORBELL_REG 0x400 37 38 #define HIDMA_EVCA_IRQ_STAT_REG 0x100 39 #define HIDMA_EVCA_IRQ_CLR_REG 0x108 40 #define HIDMA_EVCA_IRQ_EN_REG 0x110 41 42 #define HIDMA_EVRE_CFG_IDX 0 43 44 #define HIDMA_EVRE_ERRINFO_BIT_POS 24 45 #define HIDMA_EVRE_CODE_BIT_POS 28 46 47 #define HIDMA_EVRE_ERRINFO_MASK GENMASK(3, 0) 48 #define HIDMA_EVRE_CODE_MASK GENMASK(3, 0) 49 50 #define HIDMA_CH_CONTROL_MASK GENMASK(7, 0) 51 #define HIDMA_CH_STATE_MASK GENMASK(7, 0) 52 #define HIDMA_CH_STATE_BIT_POS 0x8 53 54 #define HIDMA_IRQ_EV_CH_EOB_IRQ_BIT_POS 0 55 #define HIDMA_IRQ_EV_CH_WR_RESP_BIT_POS 1 56 #define HIDMA_IRQ_TR_CH_TRE_RD_RSP_ER_BIT_POS 9 57 #define HIDMA_IRQ_TR_CH_DATA_RD_ER_BIT_POS 10 58 #define HIDMA_IRQ_TR_CH_DATA_WR_ER_BIT_POS 11 59 #define HIDMA_IRQ_TR_CH_INVALID_TRE_BIT_POS 14 60 61 #define ENABLE_IRQS (BIT(HIDMA_IRQ_EV_CH_EOB_IRQ_BIT_POS) | \ 62 BIT(HIDMA_IRQ_EV_CH_WR_RESP_BIT_POS) | \ 63 BIT(HIDMA_IRQ_TR_CH_TRE_RD_RSP_ER_BIT_POS) | \ 64 BIT(HIDMA_IRQ_TR_CH_DATA_RD_ER_BIT_POS) | \ 65 BIT(HIDMA_IRQ_TR_CH_DATA_WR_ER_BIT_POS) | \ 66 BIT(HIDMA_IRQ_TR_CH_INVALID_TRE_BIT_POS)) 67 68 #define HIDMA_INCREMENT_ITERATOR(iter, size, ring_size) \ 69 do { \ 70 iter += size; \ 71 if (iter >= ring_size) \ 72 iter -= ring_size; \ 73 } while (0) 74 75 #define HIDMA_CH_STATE(val) \ 76 ((val >> HIDMA_CH_STATE_BIT_POS) & HIDMA_CH_STATE_MASK) 77 78 #define HIDMA_ERR_INT_MASK \ 79 (BIT(HIDMA_IRQ_TR_CH_INVALID_TRE_BIT_POS) | \ 80 BIT(HIDMA_IRQ_TR_CH_TRE_RD_RSP_ER_BIT_POS) | \ 81 BIT(HIDMA_IRQ_EV_CH_WR_RESP_BIT_POS) | \ 82 BIT(HIDMA_IRQ_TR_CH_DATA_RD_ER_BIT_POS) | \ 83 BIT(HIDMA_IRQ_TR_CH_DATA_WR_ER_BIT_POS)) 84 85 enum ch_command { 86 HIDMA_CH_DISABLE = 0, 87 HIDMA_CH_ENABLE = 1, 88 HIDMA_CH_SUSPEND = 2, 89 HIDMA_CH_RESET = 9, 90 }; 91 92 enum ch_state { 93 HIDMA_CH_DISABLED = 0, 94 HIDMA_CH_ENABLED = 1, 95 HIDMA_CH_RUNNING = 2, 96 HIDMA_CH_SUSPENDED = 3, 97 HIDMA_CH_STOPPED = 4, 98 }; 99 100 enum err_code { 101 HIDMA_EVRE_STATUS_COMPLETE = 1, 102 HIDMA_EVRE_STATUS_ERROR = 4, 103 }; 104 hidma_is_chan_enabled(int state)105 static int hidma_is_chan_enabled(int state) 106 { 107 switch (state) { 108 case HIDMA_CH_ENABLED: 109 case HIDMA_CH_RUNNING: 110 return true; 111 default: 112 return false; 113 } 114 } 115 hidma_ll_free(struct hidma_lldev * lldev,u32 tre_ch)116 void hidma_ll_free(struct hidma_lldev *lldev, u32 tre_ch) 117 { 118 struct hidma_tre *tre; 119 120 if (tre_ch >= lldev->nr_tres) { 121 dev_err(lldev->dev, "invalid TRE number in free:%d", tre_ch); 122 return; 123 } 124 125 tre = &lldev->trepool[tre_ch]; 126 if (atomic_read(&tre->allocated) != true) { 127 dev_err(lldev->dev, "trying to free an unused TRE:%d", tre_ch); 128 return; 129 } 130 131 atomic_set(&tre->allocated, 0); 132 } 133 hidma_ll_request(struct hidma_lldev * lldev,u32 sig,const char * dev_name,void (* callback)(void * data),void * data,u32 * tre_ch)134 int hidma_ll_request(struct hidma_lldev *lldev, u32 sig, const char *dev_name, 135 void (*callback)(void *data), void *data, u32 *tre_ch) 136 { 137 unsigned int i; 138 struct hidma_tre *tre; 139 u32 *tre_local; 140 141 if (!tre_ch || !lldev) 142 return -EINVAL; 143 144 /* need to have at least one empty spot in the queue */ 145 for (i = 0; i < lldev->nr_tres - 1; i++) { 146 if (atomic_add_unless(&lldev->trepool[i].allocated, 1, 1)) 147 break; 148 } 149 150 if (i == (lldev->nr_tres - 1)) 151 return -ENOMEM; 152 153 tre = &lldev->trepool[i]; 154 tre->dma_sig = sig; 155 tre->dev_name = dev_name; 156 tre->callback = callback; 157 tre->data = data; 158 tre->idx = i; 159 tre->status = 0; 160 tre->queued = 0; 161 tre->err_code = 0; 162 tre->err_info = 0; 163 tre->lldev = lldev; 164 tre_local = &tre->tre_local[0]; 165 tre_local[HIDMA_TRE_CFG_IDX] = (lldev->chidx & 0xFF) << 8; 166 tre_local[HIDMA_TRE_CFG_IDX] |= BIT(16); /* set IEOB */ 167 *tre_ch = i; 168 if (callback) 169 callback(data); 170 return 0; 171 } 172 173 /* 174 * Multiple TREs may be queued and waiting in the pending queue. 175 */ hidma_ll_tre_complete(struct tasklet_struct * t)176 static void hidma_ll_tre_complete(struct tasklet_struct *t) 177 { 178 struct hidma_lldev *lldev = from_tasklet(lldev, t, task); 179 struct hidma_tre *tre; 180 181 while (kfifo_out(&lldev->handoff_fifo, &tre, 1)) { 182 /* call the user if it has been read by the hardware */ 183 if (tre->callback) 184 tre->callback(tre->data); 185 } 186 } 187 hidma_post_completed(struct hidma_lldev * lldev,u8 err_info,u8 err_code)188 static int hidma_post_completed(struct hidma_lldev *lldev, u8 err_info, 189 u8 err_code) 190 { 191 struct hidma_tre *tre; 192 unsigned long flags; 193 u32 tre_iterator; 194 195 spin_lock_irqsave(&lldev->lock, flags); 196 197 tre_iterator = lldev->tre_processed_off; 198 tre = lldev->pending_tre_list[tre_iterator / HIDMA_TRE_SIZE]; 199 if (!tre) { 200 spin_unlock_irqrestore(&lldev->lock, flags); 201 dev_warn(lldev->dev, "tre_index [%d] and tre out of sync\n", 202 tre_iterator / HIDMA_TRE_SIZE); 203 return -EINVAL; 204 } 205 lldev->pending_tre_list[tre->tre_index] = NULL; 206 207 /* 208 * Keep track of pending TREs that SW is expecting to receive 209 * from HW. We got one now. Decrement our counter. 210 */ 211 if (atomic_dec_return(&lldev->pending_tre_count) < 0) { 212 dev_warn(lldev->dev, "tre count mismatch on completion"); 213 atomic_set(&lldev->pending_tre_count, 0); 214 } 215 216 HIDMA_INCREMENT_ITERATOR(tre_iterator, HIDMA_TRE_SIZE, 217 lldev->tre_ring_size); 218 lldev->tre_processed_off = tre_iterator; 219 spin_unlock_irqrestore(&lldev->lock, flags); 220 221 tre->err_info = err_info; 222 tre->err_code = err_code; 223 tre->queued = 0; 224 225 kfifo_put(&lldev->handoff_fifo, tre); 226 tasklet_schedule(&lldev->task); 227 228 return 0; 229 } 230 231 /* 232 * Called to handle the interrupt for the channel. 233 * Return a positive number if TRE or EVRE were consumed on this run. 234 * Return a positive number if there are pending TREs or EVREs. 235 * Return 0 if there is nothing to consume or no pending TREs/EVREs found. 236 */ hidma_handle_tre_completion(struct hidma_lldev * lldev)237 static int hidma_handle_tre_completion(struct hidma_lldev *lldev) 238 { 239 u32 evre_ring_size = lldev->evre_ring_size; 240 u32 err_info, err_code, evre_write_off; 241 u32 evre_iterator; 242 u32 num_completed = 0; 243 244 evre_write_off = readl_relaxed(lldev->evca + HIDMA_EVCA_WRITE_PTR_REG); 245 evre_iterator = lldev->evre_processed_off; 246 247 if ((evre_write_off > evre_ring_size) || 248 (evre_write_off % HIDMA_EVRE_SIZE)) { 249 dev_err(lldev->dev, "HW reports invalid EVRE write offset\n"); 250 return 0; 251 } 252 253 /* 254 * By the time control reaches here the number of EVREs and TREs 255 * may not match. Only consume the ones that hardware told us. 256 */ 257 while ((evre_iterator != evre_write_off)) { 258 u32 *current_evre = lldev->evre_ring + evre_iterator; 259 u32 cfg; 260 261 cfg = current_evre[HIDMA_EVRE_CFG_IDX]; 262 err_info = cfg >> HIDMA_EVRE_ERRINFO_BIT_POS; 263 err_info &= HIDMA_EVRE_ERRINFO_MASK; 264 err_code = 265 (cfg >> HIDMA_EVRE_CODE_BIT_POS) & HIDMA_EVRE_CODE_MASK; 266 267 if (hidma_post_completed(lldev, err_info, err_code)) 268 break; 269 270 HIDMA_INCREMENT_ITERATOR(evre_iterator, HIDMA_EVRE_SIZE, 271 evre_ring_size); 272 273 /* 274 * Read the new event descriptor written by the HW. 275 * As we are processing the delivered events, other events 276 * get queued to the SW for processing. 277 */ 278 evre_write_off = 279 readl_relaxed(lldev->evca + HIDMA_EVCA_WRITE_PTR_REG); 280 num_completed++; 281 282 /* 283 * An error interrupt might have arrived while we are processing 284 * the completed interrupt. 285 */ 286 if (!hidma_ll_isenabled(lldev)) 287 break; 288 } 289 290 if (num_completed) { 291 u32 evre_read_off = (lldev->evre_processed_off + 292 HIDMA_EVRE_SIZE * num_completed); 293 evre_read_off = evre_read_off % evre_ring_size; 294 writel(evre_read_off, lldev->evca + HIDMA_EVCA_DOORBELL_REG); 295 296 /* record the last processed tre offset */ 297 lldev->evre_processed_off = evre_read_off; 298 } 299 300 return num_completed; 301 } 302 hidma_cleanup_pending_tre(struct hidma_lldev * lldev,u8 err_info,u8 err_code)303 void hidma_cleanup_pending_tre(struct hidma_lldev *lldev, u8 err_info, 304 u8 err_code) 305 { 306 while (atomic_read(&lldev->pending_tre_count)) { 307 if (hidma_post_completed(lldev, err_info, err_code)) 308 break; 309 } 310 } 311 hidma_ll_reset(struct hidma_lldev * lldev)312 static int hidma_ll_reset(struct hidma_lldev *lldev) 313 { 314 u32 val; 315 int ret; 316 317 val = readl(lldev->trca + HIDMA_TRCA_CTRLSTS_REG); 318 val &= ~(HIDMA_CH_CONTROL_MASK << 16); 319 val |= HIDMA_CH_RESET << 16; 320 writel(val, lldev->trca + HIDMA_TRCA_CTRLSTS_REG); 321 322 /* 323 * Delay 10ms after reset to allow DMA logic to quiesce. 324 * Do a polled read up to 1ms and 10ms maximum. 325 */ 326 ret = readl_poll_timeout(lldev->trca + HIDMA_TRCA_CTRLSTS_REG, val, 327 HIDMA_CH_STATE(val) == HIDMA_CH_DISABLED, 328 1000, 10000); 329 if (ret) { 330 dev_err(lldev->dev, "transfer channel did not reset\n"); 331 return ret; 332 } 333 334 val = readl(lldev->evca + HIDMA_EVCA_CTRLSTS_REG); 335 val &= ~(HIDMA_CH_CONTROL_MASK << 16); 336 val |= HIDMA_CH_RESET << 16; 337 writel(val, lldev->evca + HIDMA_EVCA_CTRLSTS_REG); 338 339 /* 340 * Delay 10ms after reset to allow DMA logic to quiesce. 341 * Do a polled read up to 1ms and 10ms maximum. 342 */ 343 ret = readl_poll_timeout(lldev->evca + HIDMA_EVCA_CTRLSTS_REG, val, 344 HIDMA_CH_STATE(val) == HIDMA_CH_DISABLED, 345 1000, 10000); 346 if (ret) 347 return ret; 348 349 lldev->trch_state = HIDMA_CH_DISABLED; 350 lldev->evch_state = HIDMA_CH_DISABLED; 351 return 0; 352 } 353 354 /* 355 * The interrupt handler for HIDMA will try to consume as many pending 356 * EVRE from the event queue as possible. Each EVRE has an associated 357 * TRE that holds the user interface parameters. EVRE reports the 358 * result of the transaction. Hardware guarantees ordering between EVREs 359 * and TREs. We use last processed offset to figure out which TRE is 360 * associated with which EVRE. If two TREs are consumed by HW, the EVREs 361 * are in order in the event ring. 362 * 363 * This handler will do a one pass for consuming EVREs. Other EVREs may 364 * be delivered while we are working. It will try to consume incoming 365 * EVREs one more time and return. 366 * 367 * For unprocessed EVREs, hardware will trigger another interrupt until 368 * all the interrupt bits are cleared. 369 * 370 * Hardware guarantees that by the time interrupt is observed, all data 371 * transactions in flight are delivered to their respective places and 372 * are visible to the CPU. 373 * 374 * On demand paging for IOMMU is only supported for PCIe via PRI 375 * (Page Request Interface) not for HIDMA. All other hardware instances 376 * including HIDMA work on pinned DMA addresses. 377 * 378 * HIDMA is not aware of IOMMU presence since it follows the DMA API. All 379 * IOMMU latency will be built into the data movement time. By the time 380 * interrupt happens, IOMMU lookups + data movement has already taken place. 381 * 382 * While the first read in a typical PCI endpoint ISR flushes all outstanding 383 * requests traditionally to the destination, this concept does not apply 384 * here for this HW. 385 */ hidma_ll_int_handler_internal(struct hidma_lldev * lldev,int cause)386 static void hidma_ll_int_handler_internal(struct hidma_lldev *lldev, int cause) 387 { 388 unsigned long irqflags; 389 390 if (cause & HIDMA_ERR_INT_MASK) { 391 dev_err(lldev->dev, "error 0x%x, disabling...\n", 392 cause); 393 394 /* Clear out pending interrupts */ 395 writel(cause, lldev->evca + HIDMA_EVCA_IRQ_CLR_REG); 396 397 /* No further submissions. */ 398 hidma_ll_disable(lldev); 399 400 /* Driver completes the txn and intimates the client.*/ 401 hidma_cleanup_pending_tre(lldev, 0xFF, 402 HIDMA_EVRE_STATUS_ERROR); 403 404 return; 405 } 406 407 spin_lock_irqsave(&lldev->lock, irqflags); 408 writel_relaxed(cause, lldev->evca + HIDMA_EVCA_IRQ_CLR_REG); 409 spin_unlock_irqrestore(&lldev->lock, irqflags); 410 411 /* 412 * Fine tuned for this HW... 413 * 414 * This ISR has been designed for this particular hardware. Relaxed 415 * read and write accessors are used for performance reasons due to 416 * interrupt delivery guarantees. Do not copy this code blindly and 417 * expect that to work. 418 * 419 * Try to consume as many EVREs as possible. 420 */ 421 hidma_handle_tre_completion(lldev); 422 } 423 hidma_ll_inthandler(int chirq,void * arg)424 irqreturn_t hidma_ll_inthandler(int chirq, void *arg) 425 { 426 struct hidma_lldev *lldev = arg; 427 u32 status; 428 u32 enable; 429 u32 cause; 430 431 status = readl_relaxed(lldev->evca + HIDMA_EVCA_IRQ_STAT_REG); 432 enable = readl_relaxed(lldev->evca + HIDMA_EVCA_IRQ_EN_REG); 433 cause = status & enable; 434 435 while (cause) { 436 hidma_ll_int_handler_internal(lldev, cause); 437 438 /* 439 * Another interrupt might have arrived while we are 440 * processing this one. Read the new cause. 441 */ 442 status = readl_relaxed(lldev->evca + HIDMA_EVCA_IRQ_STAT_REG); 443 enable = readl_relaxed(lldev->evca + HIDMA_EVCA_IRQ_EN_REG); 444 cause = status & enable; 445 } 446 447 return IRQ_HANDLED; 448 } 449 hidma_ll_inthandler_msi(int chirq,void * arg,int cause)450 irqreturn_t hidma_ll_inthandler_msi(int chirq, void *arg, int cause) 451 { 452 struct hidma_lldev *lldev = arg; 453 454 hidma_ll_int_handler_internal(lldev, cause); 455 return IRQ_HANDLED; 456 } 457 hidma_ll_enable(struct hidma_lldev * lldev)458 int hidma_ll_enable(struct hidma_lldev *lldev) 459 { 460 u32 val; 461 int ret; 462 463 val = readl(lldev->evca + HIDMA_EVCA_CTRLSTS_REG); 464 val &= ~(HIDMA_CH_CONTROL_MASK << 16); 465 val |= HIDMA_CH_ENABLE << 16; 466 writel(val, lldev->evca + HIDMA_EVCA_CTRLSTS_REG); 467 468 ret = readl_poll_timeout(lldev->evca + HIDMA_EVCA_CTRLSTS_REG, val, 469 hidma_is_chan_enabled(HIDMA_CH_STATE(val)), 470 1000, 10000); 471 if (ret) { 472 dev_err(lldev->dev, "event channel did not get enabled\n"); 473 return ret; 474 } 475 476 val = readl(lldev->trca + HIDMA_TRCA_CTRLSTS_REG); 477 val &= ~(HIDMA_CH_CONTROL_MASK << 16); 478 val |= HIDMA_CH_ENABLE << 16; 479 writel(val, lldev->trca + HIDMA_TRCA_CTRLSTS_REG); 480 481 ret = readl_poll_timeout(lldev->trca + HIDMA_TRCA_CTRLSTS_REG, val, 482 hidma_is_chan_enabled(HIDMA_CH_STATE(val)), 483 1000, 10000); 484 if (ret) { 485 dev_err(lldev->dev, "transfer channel did not get enabled\n"); 486 return ret; 487 } 488 489 lldev->trch_state = HIDMA_CH_ENABLED; 490 lldev->evch_state = HIDMA_CH_ENABLED; 491 492 /* enable irqs */ 493 writel(ENABLE_IRQS, lldev->evca + HIDMA_EVCA_IRQ_EN_REG); 494 495 return 0; 496 } 497 hidma_ll_start(struct hidma_lldev * lldev)498 void hidma_ll_start(struct hidma_lldev *lldev) 499 { 500 unsigned long irqflags; 501 502 spin_lock_irqsave(&lldev->lock, irqflags); 503 writel(lldev->tre_write_offset, lldev->trca + HIDMA_TRCA_DOORBELL_REG); 504 spin_unlock_irqrestore(&lldev->lock, irqflags); 505 } 506 hidma_ll_isenabled(struct hidma_lldev * lldev)507 bool hidma_ll_isenabled(struct hidma_lldev *lldev) 508 { 509 u32 val; 510 511 val = readl(lldev->trca + HIDMA_TRCA_CTRLSTS_REG); 512 lldev->trch_state = HIDMA_CH_STATE(val); 513 val = readl(lldev->evca + HIDMA_EVCA_CTRLSTS_REG); 514 lldev->evch_state = HIDMA_CH_STATE(val); 515 516 /* both channels have to be enabled before calling this function */ 517 if (hidma_is_chan_enabled(lldev->trch_state) && 518 hidma_is_chan_enabled(lldev->evch_state)) 519 return true; 520 521 return false; 522 } 523 hidma_ll_queue_request(struct hidma_lldev * lldev,u32 tre_ch)524 void hidma_ll_queue_request(struct hidma_lldev *lldev, u32 tre_ch) 525 { 526 struct hidma_tre *tre; 527 unsigned long flags; 528 529 tre = &lldev->trepool[tre_ch]; 530 531 /* copy the TRE into its location in the TRE ring */ 532 spin_lock_irqsave(&lldev->lock, flags); 533 tre->tre_index = lldev->tre_write_offset / HIDMA_TRE_SIZE; 534 lldev->pending_tre_list[tre->tre_index] = tre; 535 memcpy(lldev->tre_ring + lldev->tre_write_offset, 536 &tre->tre_local[0], HIDMA_TRE_SIZE); 537 tre->err_code = 0; 538 tre->err_info = 0; 539 tre->queued = 1; 540 atomic_inc(&lldev->pending_tre_count); 541 lldev->tre_write_offset = (lldev->tre_write_offset + HIDMA_TRE_SIZE) 542 % lldev->tre_ring_size; 543 spin_unlock_irqrestore(&lldev->lock, flags); 544 } 545 546 /* 547 * Note that even though we stop this channel if there is a pending transaction 548 * in flight it will complete and follow the callback. This request will 549 * prevent further requests to be made. 550 */ hidma_ll_disable(struct hidma_lldev * lldev)551 int hidma_ll_disable(struct hidma_lldev *lldev) 552 { 553 u32 val; 554 int ret; 555 556 /* The channel needs to be in working state */ 557 if (!hidma_ll_isenabled(lldev)) 558 return 0; 559 560 val = readl(lldev->trca + HIDMA_TRCA_CTRLSTS_REG); 561 val &= ~(HIDMA_CH_CONTROL_MASK << 16); 562 val |= HIDMA_CH_SUSPEND << 16; 563 writel(val, lldev->trca + HIDMA_TRCA_CTRLSTS_REG); 564 565 /* 566 * Start the wait right after the suspend is confirmed. 567 * Do a polled read up to 1ms and 10ms maximum. 568 */ 569 ret = readl_poll_timeout(lldev->trca + HIDMA_TRCA_CTRLSTS_REG, val, 570 HIDMA_CH_STATE(val) == HIDMA_CH_SUSPENDED, 571 1000, 10000); 572 if (ret) 573 return ret; 574 575 val = readl(lldev->evca + HIDMA_EVCA_CTRLSTS_REG); 576 val &= ~(HIDMA_CH_CONTROL_MASK << 16); 577 val |= HIDMA_CH_SUSPEND << 16; 578 writel(val, lldev->evca + HIDMA_EVCA_CTRLSTS_REG); 579 580 /* 581 * Start the wait right after the suspend is confirmed 582 * Delay up to 10ms after reset to allow DMA logic to quiesce. 583 */ 584 ret = readl_poll_timeout(lldev->evca + HIDMA_EVCA_CTRLSTS_REG, val, 585 HIDMA_CH_STATE(val) == HIDMA_CH_SUSPENDED, 586 1000, 10000); 587 if (ret) 588 return ret; 589 590 lldev->trch_state = HIDMA_CH_SUSPENDED; 591 lldev->evch_state = HIDMA_CH_SUSPENDED; 592 593 /* disable interrupts */ 594 writel(0, lldev->evca + HIDMA_EVCA_IRQ_EN_REG); 595 return 0; 596 } 597 hidma_ll_set_transfer_params(struct hidma_lldev * lldev,u32 tre_ch,dma_addr_t src,dma_addr_t dest,u32 len,u32 flags,u32 txntype)598 void hidma_ll_set_transfer_params(struct hidma_lldev *lldev, u32 tre_ch, 599 dma_addr_t src, dma_addr_t dest, u32 len, 600 u32 flags, u32 txntype) 601 { 602 struct hidma_tre *tre; 603 u32 *tre_local; 604 605 if (tre_ch >= lldev->nr_tres) { 606 dev_err(lldev->dev, "invalid TRE number in transfer params:%d", 607 tre_ch); 608 return; 609 } 610 611 tre = &lldev->trepool[tre_ch]; 612 if (atomic_read(&tre->allocated) != true) { 613 dev_err(lldev->dev, "trying to set params on an unused TRE:%d", 614 tre_ch); 615 return; 616 } 617 618 tre_local = &tre->tre_local[0]; 619 tre_local[HIDMA_TRE_CFG_IDX] &= ~GENMASK(7, 0); 620 tre_local[HIDMA_TRE_CFG_IDX] |= txntype; 621 tre_local[HIDMA_TRE_LEN_IDX] = len; 622 tre_local[HIDMA_TRE_SRC_LOW_IDX] = lower_32_bits(src); 623 tre_local[HIDMA_TRE_SRC_HI_IDX] = upper_32_bits(src); 624 tre_local[HIDMA_TRE_DEST_LOW_IDX] = lower_32_bits(dest); 625 tre_local[HIDMA_TRE_DEST_HI_IDX] = upper_32_bits(dest); 626 tre->int_flags = flags; 627 } 628 629 /* 630 * Called during initialization and after an error condition 631 * to restore hardware state. 632 */ hidma_ll_setup(struct hidma_lldev * lldev)633 int hidma_ll_setup(struct hidma_lldev *lldev) 634 { 635 int rc; 636 u64 addr; 637 u32 val; 638 u32 nr_tres = lldev->nr_tres; 639 640 atomic_set(&lldev->pending_tre_count, 0); 641 lldev->tre_processed_off = 0; 642 lldev->evre_processed_off = 0; 643 lldev->tre_write_offset = 0; 644 645 /* disable interrupts */ 646 writel(0, lldev->evca + HIDMA_EVCA_IRQ_EN_REG); 647 648 /* clear all pending interrupts */ 649 val = readl(lldev->evca + HIDMA_EVCA_IRQ_STAT_REG); 650 writel(val, lldev->evca + HIDMA_EVCA_IRQ_CLR_REG); 651 652 rc = hidma_ll_reset(lldev); 653 if (rc) 654 return rc; 655 656 /* 657 * Clear all pending interrupts again. 658 * Otherwise, we observe reset complete interrupts. 659 */ 660 val = readl(lldev->evca + HIDMA_EVCA_IRQ_STAT_REG); 661 writel(val, lldev->evca + HIDMA_EVCA_IRQ_CLR_REG); 662 663 /* disable interrupts again after reset */ 664 writel(0, lldev->evca + HIDMA_EVCA_IRQ_EN_REG); 665 666 addr = lldev->tre_dma; 667 writel(lower_32_bits(addr), lldev->trca + HIDMA_TRCA_RING_LOW_REG); 668 writel(upper_32_bits(addr), lldev->trca + HIDMA_TRCA_RING_HIGH_REG); 669 writel(lldev->tre_ring_size, lldev->trca + HIDMA_TRCA_RING_LEN_REG); 670 671 addr = lldev->evre_dma; 672 writel(lower_32_bits(addr), lldev->evca + HIDMA_EVCA_RING_LOW_REG); 673 writel(upper_32_bits(addr), lldev->evca + HIDMA_EVCA_RING_HIGH_REG); 674 writel(HIDMA_EVRE_SIZE * nr_tres, 675 lldev->evca + HIDMA_EVCA_RING_LEN_REG); 676 677 /* configure interrupts */ 678 hidma_ll_setup_irq(lldev, lldev->msi_support); 679 680 rc = hidma_ll_enable(lldev); 681 if (rc) 682 return rc; 683 684 return rc; 685 } 686 hidma_ll_setup_irq(struct hidma_lldev * lldev,bool msi)687 void hidma_ll_setup_irq(struct hidma_lldev *lldev, bool msi) 688 { 689 u32 val; 690 691 lldev->msi_support = msi; 692 693 /* disable interrupts again after reset */ 694 writel(0, lldev->evca + HIDMA_EVCA_IRQ_CLR_REG); 695 writel(0, lldev->evca + HIDMA_EVCA_IRQ_EN_REG); 696 697 /* support IRQ by default */ 698 val = readl(lldev->evca + HIDMA_EVCA_INTCTRL_REG); 699 val &= ~0xF; 700 if (!lldev->msi_support) 701 val = val | 0x1; 702 writel(val, lldev->evca + HIDMA_EVCA_INTCTRL_REG); 703 704 /* clear all pending interrupts and enable them */ 705 writel(ENABLE_IRQS, lldev->evca + HIDMA_EVCA_IRQ_CLR_REG); 706 writel(ENABLE_IRQS, lldev->evca + HIDMA_EVCA_IRQ_EN_REG); 707 } 708 hidma_ll_init(struct device * dev,u32 nr_tres,void __iomem * trca,void __iomem * evca,u8 chidx)709 struct hidma_lldev *hidma_ll_init(struct device *dev, u32 nr_tres, 710 void __iomem *trca, void __iomem *evca, 711 u8 chidx) 712 { 713 u32 required_bytes; 714 struct hidma_lldev *lldev; 715 int rc; 716 size_t sz; 717 718 if (!trca || !evca || !dev || !nr_tres) 719 return NULL; 720 721 /* need at least four TREs */ 722 if (nr_tres < 4) 723 return NULL; 724 725 /* need an extra space */ 726 nr_tres += 1; 727 728 lldev = devm_kzalloc(dev, sizeof(struct hidma_lldev), GFP_KERNEL); 729 if (!lldev) 730 return NULL; 731 732 lldev->evca = evca; 733 lldev->trca = trca; 734 lldev->dev = dev; 735 sz = sizeof(struct hidma_tre); 736 lldev->trepool = devm_kcalloc(lldev->dev, nr_tres, sz, GFP_KERNEL); 737 if (!lldev->trepool) 738 return NULL; 739 740 required_bytes = sizeof(lldev->pending_tre_list[0]); 741 lldev->pending_tre_list = devm_kcalloc(dev, nr_tres, required_bytes, 742 GFP_KERNEL); 743 if (!lldev->pending_tre_list) 744 return NULL; 745 746 sz = (HIDMA_TRE_SIZE + 1) * nr_tres; 747 lldev->tre_ring = dmam_alloc_coherent(dev, sz, &lldev->tre_dma, 748 GFP_KERNEL); 749 if (!lldev->tre_ring) 750 return NULL; 751 752 lldev->tre_ring_size = HIDMA_TRE_SIZE * nr_tres; 753 lldev->nr_tres = nr_tres; 754 755 /* the TRE ring has to be TRE_SIZE aligned */ 756 if (!IS_ALIGNED(lldev->tre_dma, HIDMA_TRE_SIZE)) { 757 u8 tre_ring_shift; 758 759 tre_ring_shift = lldev->tre_dma % HIDMA_TRE_SIZE; 760 tre_ring_shift = HIDMA_TRE_SIZE - tre_ring_shift; 761 lldev->tre_dma += tre_ring_shift; 762 lldev->tre_ring += tre_ring_shift; 763 } 764 765 sz = (HIDMA_EVRE_SIZE + 1) * nr_tres; 766 lldev->evre_ring = dmam_alloc_coherent(dev, sz, &lldev->evre_dma, 767 GFP_KERNEL); 768 if (!lldev->evre_ring) 769 return NULL; 770 771 lldev->evre_ring_size = HIDMA_EVRE_SIZE * nr_tres; 772 773 /* the EVRE ring has to be EVRE_SIZE aligned */ 774 if (!IS_ALIGNED(lldev->evre_dma, HIDMA_EVRE_SIZE)) { 775 u8 evre_ring_shift; 776 777 evre_ring_shift = lldev->evre_dma % HIDMA_EVRE_SIZE; 778 evre_ring_shift = HIDMA_EVRE_SIZE - evre_ring_shift; 779 lldev->evre_dma += evre_ring_shift; 780 lldev->evre_ring += evre_ring_shift; 781 } 782 lldev->nr_tres = nr_tres; 783 lldev->chidx = chidx; 784 785 sz = nr_tres * sizeof(struct hidma_tre *); 786 rc = kfifo_alloc(&lldev->handoff_fifo, sz, GFP_KERNEL); 787 if (rc) 788 return NULL; 789 790 rc = hidma_ll_setup(lldev); 791 if (rc) 792 return NULL; 793 794 spin_lock_init(&lldev->lock); 795 tasklet_setup(&lldev->task, hidma_ll_tre_complete); 796 lldev->initialized = 1; 797 writel(ENABLE_IRQS, lldev->evca + HIDMA_EVCA_IRQ_EN_REG); 798 return lldev; 799 } 800 hidma_ll_uninit(struct hidma_lldev * lldev)801 int hidma_ll_uninit(struct hidma_lldev *lldev) 802 { 803 u32 required_bytes; 804 int rc = 0; 805 u32 val; 806 807 if (!lldev) 808 return -ENODEV; 809 810 if (!lldev->initialized) 811 return 0; 812 813 lldev->initialized = 0; 814 815 required_bytes = sizeof(struct hidma_tre) * lldev->nr_tres; 816 tasklet_kill(&lldev->task); 817 memset(lldev->trepool, 0, required_bytes); 818 lldev->trepool = NULL; 819 atomic_set(&lldev->pending_tre_count, 0); 820 lldev->tre_write_offset = 0; 821 822 rc = hidma_ll_reset(lldev); 823 824 /* 825 * Clear all pending interrupts again. 826 * Otherwise, we observe reset complete interrupts. 827 */ 828 val = readl(lldev->evca + HIDMA_EVCA_IRQ_STAT_REG); 829 writel(val, lldev->evca + HIDMA_EVCA_IRQ_CLR_REG); 830 writel(0, lldev->evca + HIDMA_EVCA_IRQ_EN_REG); 831 return rc; 832 } 833 hidma_ll_status(struct hidma_lldev * lldev,u32 tre_ch)834 enum dma_status hidma_ll_status(struct hidma_lldev *lldev, u32 tre_ch) 835 { 836 enum dma_status ret = DMA_ERROR; 837 struct hidma_tre *tre; 838 unsigned long flags; 839 u8 err_code; 840 841 spin_lock_irqsave(&lldev->lock, flags); 842 843 tre = &lldev->trepool[tre_ch]; 844 err_code = tre->err_code; 845 846 if (err_code & HIDMA_EVRE_STATUS_COMPLETE) 847 ret = DMA_COMPLETE; 848 else if (err_code & HIDMA_EVRE_STATUS_ERROR) 849 ret = DMA_ERROR; 850 else 851 ret = DMA_IN_PROGRESS; 852 spin_unlock_irqrestore(&lldev->lock, flags); 853 854 return ret; 855 } 856