1// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0 2/* Copyright (c) 2019-2020 Marvell International Ltd. All rights reserved */ 3 4#include <linux/bitfield.h> 5#include <linux/dmapool.h> 6#include <linux/etherdevice.h> 7#include <linux/if_vlan.h> 8#include <linux/platform_device.h> 9 10#include "prestera_dsa.h" 11#include "prestera.h" 12#include "prestera_hw.h" 13#include "prestera_rxtx.h" 14#include "prestera_devlink.h" 15 16#define PRESTERA_SDMA_WAIT_MUL 10 17 18struct prestera_sdma_desc { 19 __le32 word1; 20 __le32 word2; 21 __le32 buff; 22 __le32 next; 23} __packed __aligned(16); 24 25#define PRESTERA_SDMA_BUFF_SIZE_MAX 1544 26 27#define PRESTERA_SDMA_RX_DESC_PKT_LEN(desc) \ 28 ((le32_to_cpu((desc)->word2) >> 16) & GENMASK(13, 0)) 29 30#define PRESTERA_SDMA_RX_DESC_OWNER(desc) \ 31 ((le32_to_cpu((desc)->word1) & BIT(31)) >> 31) 32 33#define PRESTERA_SDMA_RX_DESC_IS_RCVD(desc) \ 34 (PRESTERA_SDMA_RX_DESC_OWNER(desc) == PRESTERA_SDMA_RX_DESC_CPU_OWN) 35 36#define PRESTERA_SDMA_RX_DESC_CPU_OWN 0 37#define PRESTERA_SDMA_RX_DESC_DMA_OWN 1 38 39#define PRESTERA_SDMA_RX_QUEUE_NUM 8 40 41#define PRESTERA_SDMA_RX_DESC_PER_Q 1000 42 43#define PRESTERA_SDMA_TX_DESC_PER_Q 1000 44#define PRESTERA_SDMA_TX_MAX_BURST 64 45 46#define PRESTERA_SDMA_TX_DESC_OWNER(desc) \ 47 ((le32_to_cpu((desc)->word1) & BIT(31)) >> 31) 48 49#define PRESTERA_SDMA_TX_DESC_CPU_OWN 0 50#define PRESTERA_SDMA_TX_DESC_DMA_OWN 1U 51 52#define PRESTERA_SDMA_TX_DESC_IS_SENT(desc) \ 53 (PRESTERA_SDMA_TX_DESC_OWNER(desc) == PRESTERA_SDMA_TX_DESC_CPU_OWN) 54 55#define PRESTERA_SDMA_TX_DESC_LAST BIT(20) 56#define PRESTERA_SDMA_TX_DESC_FIRST BIT(21) 57#define PRESTERA_SDMA_TX_DESC_CALC_CRC BIT(12) 58 59#define PRESTERA_SDMA_TX_DESC_SINGLE \ 60 (PRESTERA_SDMA_TX_DESC_FIRST | PRESTERA_SDMA_TX_DESC_LAST) 61 62#define PRESTERA_SDMA_TX_DESC_INIT \ 63 (PRESTERA_SDMA_TX_DESC_SINGLE | PRESTERA_SDMA_TX_DESC_CALC_CRC) 64 65#define PRESTERA_SDMA_RX_INTR_MASK_REG 0x2814 66#define PRESTERA_SDMA_RX_QUEUE_STATUS_REG 0x2680 67#define PRESTERA_SDMA_RX_QUEUE_DESC_REG(n) (0x260C + (n) * 16) 68 69#define PRESTERA_SDMA_TX_QUEUE_DESC_REG 0x26C0 70#define PRESTERA_SDMA_TX_QUEUE_START_REG 0x2868 71 72struct prestera_sdma_buf { 73 struct prestera_sdma_desc *desc; 74 dma_addr_t desc_dma; 75 struct sk_buff *skb; 76 dma_addr_t buf_dma; 77 bool is_used; 78}; 79 80struct prestera_rx_ring { 81 struct prestera_sdma_buf *bufs; 82 int next_rx; 83}; 84 85struct prestera_tx_ring { 86 struct prestera_sdma_buf *bufs; 87 int next_tx; 88 int max_burst; 89 int burst; 90}; 91 92struct prestera_sdma { 93 struct prestera_rx_ring rx_ring[PRESTERA_SDMA_RX_QUEUE_NUM]; 94 struct prestera_tx_ring tx_ring; 95 struct prestera_switch *sw; 96 struct dma_pool *desc_pool; 97 struct work_struct tx_work; 98 struct napi_struct rx_napi; 99 struct net_device napi_dev; 100 u32 map_addr; 101 u64 dma_mask; 102 /* protect SDMA with concurrent access from multiple CPUs */ 103 spinlock_t tx_lock; 104}; 105 106struct prestera_rxtx { 107 struct prestera_sdma sdma; 108}; 109 110static int prestera_sdma_buf_init(struct prestera_sdma *sdma, 111 struct prestera_sdma_buf *buf) 112{ 113 struct prestera_sdma_desc *desc; 114 dma_addr_t dma; 115 116 desc = dma_pool_alloc(sdma->desc_pool, GFP_DMA | GFP_KERNEL, &dma); 117 if (!desc) 118 return -ENOMEM; 119 120 buf->buf_dma = DMA_MAPPING_ERROR; 121 buf->desc_dma = dma; 122 buf->desc = desc; 123 buf->skb = NULL; 124 125 return 0; 126} 127 128static u32 prestera_sdma_map(struct prestera_sdma *sdma, dma_addr_t pa) 129{ 130 return sdma->map_addr + pa; 131} 132 133static void prestera_sdma_rx_desc_init(struct prestera_sdma *sdma, 134 struct prestera_sdma_desc *desc, 135 dma_addr_t buf) 136{ 137 u32 word = le32_to_cpu(desc->word2); 138 139 u32p_replace_bits(&word, PRESTERA_SDMA_BUFF_SIZE_MAX, GENMASK(15, 0)); 140 desc->word2 = cpu_to_le32(word); 141 142 desc->buff = cpu_to_le32(prestera_sdma_map(sdma, buf)); 143 144 /* make sure buffer is set before reset the descriptor */ 145 wmb(); 146 147 desc->word1 = cpu_to_le32(0xA0000000); 148} 149 150static void prestera_sdma_rx_desc_set_next(struct prestera_sdma *sdma, 151 struct prestera_sdma_desc *desc, 152 dma_addr_t next) 153{ 154 desc->next = cpu_to_le32(prestera_sdma_map(sdma, next)); 155} 156 157static int prestera_sdma_rx_skb_alloc(struct prestera_sdma *sdma, 158 struct prestera_sdma_buf *buf) 159{ 160 struct device *dev = sdma->sw->dev->dev; 161 struct sk_buff *skb; 162 dma_addr_t dma; 163 164 skb = alloc_skb(PRESTERA_SDMA_BUFF_SIZE_MAX, GFP_DMA | GFP_ATOMIC); 165 if (!skb) 166 return -ENOMEM; 167 168 dma = dma_map_single(dev, skb->data, skb->len, DMA_FROM_DEVICE); 169 if (dma_mapping_error(dev, dma)) 170 goto err_dma_map; 171 172 if (buf->skb) 173 dma_unmap_single(dev, buf->buf_dma, buf->skb->len, 174 DMA_FROM_DEVICE); 175 176 buf->buf_dma = dma; 177 buf->skb = skb; 178 179 return 0; 180 181err_dma_map: 182 kfree_skb(skb); 183 184 return -ENOMEM; 185} 186 187static struct sk_buff *prestera_sdma_rx_skb_get(struct prestera_sdma *sdma, 188 struct prestera_sdma_buf *buf) 189{ 190 dma_addr_t buf_dma = buf->buf_dma; 191 struct sk_buff *skb = buf->skb; 192 u32 len = skb->len; 193 int err; 194 195 err = prestera_sdma_rx_skb_alloc(sdma, buf); 196 if (err) { 197 buf->buf_dma = buf_dma; 198 buf->skb = skb; 199 200 skb = alloc_skb(skb->len, GFP_ATOMIC); 201 if (skb) { 202 skb_put(skb, len); 203 skb_copy_from_linear_data(buf->skb, skb->data, len); 204 } 205 } 206 207 prestera_sdma_rx_desc_init(sdma, buf->desc, buf->buf_dma); 208 209 return skb; 210} 211 212static int prestera_rxtx_process_skb(struct prestera_sdma *sdma, 213 struct sk_buff *skb) 214{ 215 struct prestera_port *port; 216 struct prestera_dsa dsa; 217 u32 hw_port, dev_id; 218 u8 cpu_code; 219 int err; 220 221 skb_pull(skb, ETH_HLEN); 222 223 /* ethertype field is part of the dsa header */ 224 err = prestera_dsa_parse(&dsa, skb->data - ETH_TLEN); 225 if (err) 226 return err; 227 228 dev_id = dsa.hw_dev_num; 229 hw_port = dsa.port_num; 230 231 port = prestera_port_find_by_hwid(sdma->sw, dev_id, hw_port); 232 if (unlikely(!port)) { 233 dev_warn_ratelimited(prestera_dev(sdma->sw), "received pkt for non-existent port(%u, %u)\n", 234 dev_id, hw_port); 235 return -ENOENT; 236 } 237 238 if (unlikely(!pskb_may_pull(skb, PRESTERA_DSA_HLEN))) 239 return -EINVAL; 240 241 /* remove DSA tag and update checksum */ 242 skb_pull_rcsum(skb, PRESTERA_DSA_HLEN); 243 244 memmove(skb->data - ETH_HLEN, skb->data - ETH_HLEN - PRESTERA_DSA_HLEN, 245 ETH_ALEN * 2); 246 247 skb_push(skb, ETH_HLEN); 248 249 skb->protocol = eth_type_trans(skb, port->dev); 250 251 if (dsa.vlan.is_tagged) { 252 u16 tci = dsa.vlan.vid & VLAN_VID_MASK; 253 254 tci |= dsa.vlan.vpt << VLAN_PRIO_SHIFT; 255 if (dsa.vlan.cfi_bit) 256 tci |= VLAN_CFI_MASK; 257 258 __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), tci); 259 } 260 261 cpu_code = dsa.cpu_code; 262 prestera_devlink_trap_report(port, skb, cpu_code); 263 264 return 0; 265} 266 267static int prestera_sdma_next_rx_buf_idx(int buf_idx) 268{ 269 return (buf_idx + 1) % PRESTERA_SDMA_RX_DESC_PER_Q; 270} 271 272static int prestera_sdma_rx_poll(struct napi_struct *napi, int budget) 273{ 274 int qnum = PRESTERA_SDMA_RX_QUEUE_NUM; 275 unsigned int rxq_done_map = 0; 276 struct prestera_sdma *sdma; 277 struct list_head rx_list; 278 unsigned int qmask; 279 int pkts_done = 0; 280 int q; 281 282 qnum = PRESTERA_SDMA_RX_QUEUE_NUM; 283 qmask = GENMASK(qnum - 1, 0); 284 285 INIT_LIST_HEAD(&rx_list); 286 287 sdma = container_of(napi, struct prestera_sdma, rx_napi); 288 289 while (pkts_done < budget && rxq_done_map != qmask) { 290 for (q = 0; q < qnum && pkts_done < budget; q++) { 291 struct prestera_rx_ring *ring = &sdma->rx_ring[q]; 292 struct prestera_sdma_desc *desc; 293 struct prestera_sdma_buf *buf; 294 int buf_idx = ring->next_rx; 295 struct sk_buff *skb; 296 297 buf = &ring->bufs[buf_idx]; 298 desc = buf->desc; 299 300 if (PRESTERA_SDMA_RX_DESC_IS_RCVD(desc)) { 301 rxq_done_map &= ~BIT(q); 302 } else { 303 rxq_done_map |= BIT(q); 304 continue; 305 } 306 307 pkts_done++; 308 309 __skb_trim(buf->skb, PRESTERA_SDMA_RX_DESC_PKT_LEN(desc)); 310 311 skb = prestera_sdma_rx_skb_get(sdma, buf); 312 if (!skb) 313 goto rx_next_buf; 314 315 if (unlikely(prestera_rxtx_process_skb(sdma, skb))) 316 goto rx_next_buf; 317 318 list_add_tail(&skb->list, &rx_list); 319rx_next_buf: 320 ring->next_rx = prestera_sdma_next_rx_buf_idx(buf_idx); 321 } 322 } 323 324 if (pkts_done < budget && napi_complete_done(napi, pkts_done)) 325 prestera_write(sdma->sw, PRESTERA_SDMA_RX_INTR_MASK_REG, 326 GENMASK(9, 2)); 327 328 netif_receive_skb_list(&rx_list); 329 330 return pkts_done; 331} 332 333static void prestera_sdma_rx_fini(struct prestera_sdma *sdma) 334{ 335 int qnum = PRESTERA_SDMA_RX_QUEUE_NUM; 336 int q, b; 337 338 /* disable all rx queues */ 339 prestera_write(sdma->sw, PRESTERA_SDMA_RX_QUEUE_STATUS_REG, 340 GENMASK(15, 8)); 341 342 for (q = 0; q < qnum; q++) { 343 struct prestera_rx_ring *ring = &sdma->rx_ring[q]; 344 345 if (!ring->bufs) 346 break; 347 348 for (b = 0; b < PRESTERA_SDMA_RX_DESC_PER_Q; b++) { 349 struct prestera_sdma_buf *buf = &ring->bufs[b]; 350 351 if (buf->desc_dma) 352 dma_pool_free(sdma->desc_pool, buf->desc, 353 buf->desc_dma); 354 355 if (!buf->skb) 356 continue; 357 358 if (buf->buf_dma != DMA_MAPPING_ERROR) 359 dma_unmap_single(sdma->sw->dev->dev, 360 buf->buf_dma, buf->skb->len, 361 DMA_FROM_DEVICE); 362 kfree_skb(buf->skb); 363 } 364 } 365} 366 367static int prestera_sdma_rx_init(struct prestera_sdma *sdma) 368{ 369 int bnum = PRESTERA_SDMA_RX_DESC_PER_Q; 370 int qnum = PRESTERA_SDMA_RX_QUEUE_NUM; 371 int err; 372 int q; 373 374 /* disable all rx queues */ 375 prestera_write(sdma->sw, PRESTERA_SDMA_RX_QUEUE_STATUS_REG, 376 GENMASK(15, 8)); 377 378 for (q = 0; q < qnum; q++) { 379 struct prestera_sdma_buf *head, *tail, *next, *prev; 380 struct prestera_rx_ring *ring = &sdma->rx_ring[q]; 381 382 ring->bufs = kmalloc_array(bnum, sizeof(*head), GFP_KERNEL); 383 if (!ring->bufs) 384 return -ENOMEM; 385 386 ring->next_rx = 0; 387 388 tail = &ring->bufs[bnum - 1]; 389 head = &ring->bufs[0]; 390 next = head; 391 prev = next; 392 393 do { 394 err = prestera_sdma_buf_init(sdma, next); 395 if (err) 396 return err; 397 398 err = prestera_sdma_rx_skb_alloc(sdma, next); 399 if (err) 400 return err; 401 402 prestera_sdma_rx_desc_init(sdma, next->desc, 403 next->buf_dma); 404 405 prestera_sdma_rx_desc_set_next(sdma, prev->desc, 406 next->desc_dma); 407 408 prev = next; 409 next++; 410 } while (prev != tail); 411 412 /* join tail with head to make a circular list */ 413 prestera_sdma_rx_desc_set_next(sdma, tail->desc, head->desc_dma); 414 415 prestera_write(sdma->sw, PRESTERA_SDMA_RX_QUEUE_DESC_REG(q), 416 prestera_sdma_map(sdma, head->desc_dma)); 417 } 418 419 /* make sure all rx descs are filled before enabling all rx queues */ 420 wmb(); 421 422 prestera_write(sdma->sw, PRESTERA_SDMA_RX_QUEUE_STATUS_REG, 423 GENMASK(7, 0)); 424 425 return 0; 426} 427 428static void prestera_sdma_tx_desc_init(struct prestera_sdma *sdma, 429 struct prestera_sdma_desc *desc) 430{ 431 desc->word1 = cpu_to_le32(PRESTERA_SDMA_TX_DESC_INIT); 432 desc->word2 = 0; 433} 434 435static void prestera_sdma_tx_desc_set_next(struct prestera_sdma *sdma, 436 struct prestera_sdma_desc *desc, 437 dma_addr_t next) 438{ 439 desc->next = cpu_to_le32(prestera_sdma_map(sdma, next)); 440} 441 442static void prestera_sdma_tx_desc_set_buf(struct prestera_sdma *sdma, 443 struct prestera_sdma_desc *desc, 444 dma_addr_t buf, size_t len) 445{ 446 u32 word = le32_to_cpu(desc->word2); 447 448 u32p_replace_bits(&word, len + ETH_FCS_LEN, GENMASK(30, 16)); 449 450 desc->buff = cpu_to_le32(prestera_sdma_map(sdma, buf)); 451 desc->word2 = cpu_to_le32(word); 452} 453 454static void prestera_sdma_tx_desc_xmit(struct prestera_sdma_desc *desc) 455{ 456 u32 word = le32_to_cpu(desc->word1); 457 458 word |= PRESTERA_SDMA_TX_DESC_DMA_OWN << 31; 459 460 /* make sure everything is written before enable xmit */ 461 wmb(); 462 463 desc->word1 = cpu_to_le32(word); 464} 465 466static int prestera_sdma_tx_buf_map(struct prestera_sdma *sdma, 467 struct prestera_sdma_buf *buf, 468 struct sk_buff *skb) 469{ 470 struct device *dma_dev = sdma->sw->dev->dev; 471 dma_addr_t dma; 472 473 dma = dma_map_single(dma_dev, skb->data, skb->len, DMA_TO_DEVICE); 474 if (dma_mapping_error(dma_dev, dma)) 475 return -ENOMEM; 476 477 buf->buf_dma = dma; 478 buf->skb = skb; 479 480 return 0; 481} 482 483static void prestera_sdma_tx_buf_unmap(struct prestera_sdma *sdma, 484 struct prestera_sdma_buf *buf) 485{ 486 struct device *dma_dev = sdma->sw->dev->dev; 487 488 dma_unmap_single(dma_dev, buf->buf_dma, buf->skb->len, DMA_TO_DEVICE); 489} 490 491static void prestera_sdma_tx_recycle_work_fn(struct work_struct *work) 492{ 493 int bnum = PRESTERA_SDMA_TX_DESC_PER_Q; 494 struct prestera_tx_ring *tx_ring; 495 struct prestera_sdma *sdma; 496 int b; 497 498 sdma = container_of(work, struct prestera_sdma, tx_work); 499 500 tx_ring = &sdma->tx_ring; 501 502 for (b = 0; b < bnum; b++) { 503 struct prestera_sdma_buf *buf = &tx_ring->bufs[b]; 504 505 if (!buf->is_used) 506 continue; 507 508 if (!PRESTERA_SDMA_TX_DESC_IS_SENT(buf->desc)) 509 continue; 510 511 prestera_sdma_tx_buf_unmap(sdma, buf); 512 dev_consume_skb_any(buf->skb); 513 buf->skb = NULL; 514 515 /* make sure everything is cleaned up */ 516 wmb(); 517 518 buf->is_used = false; 519 } 520} 521 522static int prestera_sdma_tx_init(struct prestera_sdma *sdma) 523{ 524 struct prestera_sdma_buf *head, *tail, *next, *prev; 525 struct prestera_tx_ring *tx_ring = &sdma->tx_ring; 526 int bnum = PRESTERA_SDMA_TX_DESC_PER_Q; 527 int err; 528 529 INIT_WORK(&sdma->tx_work, prestera_sdma_tx_recycle_work_fn); 530 spin_lock_init(&sdma->tx_lock); 531 532 tx_ring->bufs = kmalloc_array(bnum, sizeof(*head), GFP_KERNEL); 533 if (!tx_ring->bufs) 534 return -ENOMEM; 535 536 tail = &tx_ring->bufs[bnum - 1]; 537 head = &tx_ring->bufs[0]; 538 next = head; 539 prev = next; 540 541 tx_ring->max_burst = PRESTERA_SDMA_TX_MAX_BURST; 542 tx_ring->burst = tx_ring->max_burst; 543 tx_ring->next_tx = 0; 544 545 do { 546 err = prestera_sdma_buf_init(sdma, next); 547 if (err) 548 return err; 549 550 next->is_used = false; 551 552 prestera_sdma_tx_desc_init(sdma, next->desc); 553 554 prestera_sdma_tx_desc_set_next(sdma, prev->desc, 555 next->desc_dma); 556 557 prev = next; 558 next++; 559 } while (prev != tail); 560 561 /* join tail with head to make a circular list */ 562 prestera_sdma_tx_desc_set_next(sdma, tail->desc, head->desc_dma); 563 564 /* make sure descriptors are written */ 565 wmb(); 566 567 prestera_write(sdma->sw, PRESTERA_SDMA_TX_QUEUE_DESC_REG, 568 prestera_sdma_map(sdma, head->desc_dma)); 569 570 return 0; 571} 572 573static void prestera_sdma_tx_fini(struct prestera_sdma *sdma) 574{ 575 struct prestera_tx_ring *ring = &sdma->tx_ring; 576 int bnum = PRESTERA_SDMA_TX_DESC_PER_Q; 577 int b; 578 579 cancel_work_sync(&sdma->tx_work); 580 581 if (!ring->bufs) 582 return; 583 584 for (b = 0; b < bnum; b++) { 585 struct prestera_sdma_buf *buf = &ring->bufs[b]; 586 587 if (buf->desc) 588 dma_pool_free(sdma->desc_pool, buf->desc, 589 buf->desc_dma); 590 591 if (!buf->skb) 592 continue; 593 594 dma_unmap_single(sdma->sw->dev->dev, buf->buf_dma, 595 buf->skb->len, DMA_TO_DEVICE); 596 597 dev_consume_skb_any(buf->skb); 598 } 599} 600 601static void prestera_rxtx_handle_event(struct prestera_switch *sw, 602 struct prestera_event *evt, 603 void *arg) 604{ 605 struct prestera_sdma *sdma = arg; 606 607 if (evt->id != PRESTERA_RXTX_EVENT_RCV_PKT) 608 return; 609 610 prestera_write(sdma->sw, PRESTERA_SDMA_RX_INTR_MASK_REG, 0); 611 napi_schedule(&sdma->rx_napi); 612} 613 614static int prestera_sdma_switch_init(struct prestera_switch *sw) 615{ 616 struct prestera_sdma *sdma = &sw->rxtx->sdma; 617 struct device *dev = sw->dev->dev; 618 struct prestera_rxtx_params p; 619 int err; 620 621 p.use_sdma = true; 622 623 err = prestera_hw_rxtx_init(sw, &p); 624 if (err) { 625 dev_err(dev, "failed to init rxtx by hw\n"); 626 return err; 627 } 628 629 sdma->dma_mask = dma_get_mask(dev); 630 sdma->map_addr = p.map_addr; 631 sdma->sw = sw; 632 633 sdma->desc_pool = dma_pool_create("desc_pool", dev, 634 sizeof(struct prestera_sdma_desc), 635 16, 0); 636 if (!sdma->desc_pool) 637 return -ENOMEM; 638 639 err = prestera_sdma_rx_init(sdma); 640 if (err) { 641 dev_err(dev, "failed to init rx ring\n"); 642 goto err_rx_init; 643 } 644 645 err = prestera_sdma_tx_init(sdma); 646 if (err) { 647 dev_err(dev, "failed to init tx ring\n"); 648 goto err_tx_init; 649 } 650 651 err = prestera_hw_event_handler_register(sw, PRESTERA_EVENT_TYPE_RXTX, 652 prestera_rxtx_handle_event, 653 sdma); 654 if (err) 655 goto err_evt_register; 656 657 init_dummy_netdev(&sdma->napi_dev); 658 659 netif_napi_add(&sdma->napi_dev, &sdma->rx_napi, prestera_sdma_rx_poll); 660 napi_enable(&sdma->rx_napi); 661 662 return 0; 663 664err_evt_register: 665err_tx_init: 666 prestera_sdma_tx_fini(sdma); 667err_rx_init: 668 prestera_sdma_rx_fini(sdma); 669 670 dma_pool_destroy(sdma->desc_pool); 671 return err; 672} 673 674static void prestera_sdma_switch_fini(struct prestera_switch *sw) 675{ 676 struct prestera_sdma *sdma = &sw->rxtx->sdma; 677 678 napi_disable(&sdma->rx_napi); 679 netif_napi_del(&sdma->rx_napi); 680 prestera_hw_event_handler_unregister(sw, PRESTERA_EVENT_TYPE_RXTX, 681 prestera_rxtx_handle_event); 682 prestera_sdma_tx_fini(sdma); 683 prestera_sdma_rx_fini(sdma); 684 dma_pool_destroy(sdma->desc_pool); 685} 686 687static bool prestera_sdma_is_ready(struct prestera_sdma *sdma) 688{ 689 return !(prestera_read(sdma->sw, PRESTERA_SDMA_TX_QUEUE_START_REG) & 1); 690} 691 692static int prestera_sdma_tx_wait(struct prestera_sdma *sdma, 693 struct prestera_tx_ring *tx_ring) 694{ 695 int tx_wait_num = PRESTERA_SDMA_WAIT_MUL * tx_ring->max_burst; 696 697 do { 698 if (prestera_sdma_is_ready(sdma)) 699 return 0; 700 701 udelay(1); 702 } while (--tx_wait_num); 703 704 return -EBUSY; 705} 706 707static void prestera_sdma_tx_start(struct prestera_sdma *sdma) 708{ 709 prestera_write(sdma->sw, PRESTERA_SDMA_TX_QUEUE_START_REG, 1); 710 schedule_work(&sdma->tx_work); 711} 712 713static netdev_tx_t prestera_sdma_xmit(struct prestera_sdma *sdma, 714 struct sk_buff *skb) 715{ 716 struct device *dma_dev = sdma->sw->dev->dev; 717 struct net_device *dev = skb->dev; 718 struct prestera_tx_ring *tx_ring; 719 struct prestera_sdma_buf *buf; 720 int err; 721 722 spin_lock(&sdma->tx_lock); 723 724 tx_ring = &sdma->tx_ring; 725 726 buf = &tx_ring->bufs[tx_ring->next_tx]; 727 if (buf->is_used) { 728 schedule_work(&sdma->tx_work); 729 goto drop_skb; 730 } 731 732 if (unlikely(eth_skb_pad(skb))) 733 goto drop_skb_nofree; 734 735 err = prestera_sdma_tx_buf_map(sdma, buf, skb); 736 if (err) 737 goto drop_skb; 738 739 prestera_sdma_tx_desc_set_buf(sdma, buf->desc, buf->buf_dma, skb->len); 740 741 dma_sync_single_for_device(dma_dev, buf->buf_dma, skb->len, 742 DMA_TO_DEVICE); 743 744 if (tx_ring->burst) { 745 tx_ring->burst--; 746 } else { 747 tx_ring->burst = tx_ring->max_burst; 748 749 err = prestera_sdma_tx_wait(sdma, tx_ring); 750 if (err) 751 goto drop_skb_unmap; 752 } 753 754 tx_ring->next_tx = (tx_ring->next_tx + 1) % PRESTERA_SDMA_TX_DESC_PER_Q; 755 prestera_sdma_tx_desc_xmit(buf->desc); 756 buf->is_used = true; 757 758 prestera_sdma_tx_start(sdma); 759 760 goto tx_done; 761 762drop_skb_unmap: 763 prestera_sdma_tx_buf_unmap(sdma, buf); 764drop_skb: 765 dev_consume_skb_any(skb); 766drop_skb_nofree: 767 dev->stats.tx_dropped++; 768tx_done: 769 spin_unlock(&sdma->tx_lock); 770 return NETDEV_TX_OK; 771} 772 773int prestera_rxtx_switch_init(struct prestera_switch *sw) 774{ 775 struct prestera_rxtx *rxtx; 776 int err; 777 778 rxtx = kzalloc(sizeof(*rxtx), GFP_KERNEL); 779 if (!rxtx) 780 return -ENOMEM; 781 782 sw->rxtx = rxtx; 783 784 err = prestera_sdma_switch_init(sw); 785 if (err) 786 kfree(rxtx); 787 788 return err; 789} 790 791void prestera_rxtx_switch_fini(struct prestera_switch *sw) 792{ 793 prestera_sdma_switch_fini(sw); 794 kfree(sw->rxtx); 795} 796 797int prestera_rxtx_port_init(struct prestera_port *port) 798{ 799 port->dev->needed_headroom = PRESTERA_DSA_HLEN; 800 return 0; 801} 802 803netdev_tx_t prestera_rxtx_xmit(struct prestera_port *port, struct sk_buff *skb) 804{ 805 struct prestera_dsa dsa; 806 807 dsa.hw_dev_num = port->dev_id; 808 dsa.port_num = port->hw_id; 809 810 if (skb_cow_head(skb, PRESTERA_DSA_HLEN) < 0) 811 return NET_XMIT_DROP; 812 813 skb_push(skb, PRESTERA_DSA_HLEN); 814 memmove(skb->data, skb->data + PRESTERA_DSA_HLEN, 2 * ETH_ALEN); 815 816 if (prestera_dsa_build(&dsa, skb->data + 2 * ETH_ALEN) != 0) 817 return NET_XMIT_DROP; 818 819 return prestera_sdma_xmit(&port->sw->rxtx->sdma, skb); 820} 821