1 /* 2 * Copyright (c) 2011, 2012, Qualcomm Atheros Communications Inc. 3 * Copyright (c) 2014, I2SE GmbH 4 * 5 * Permission to use, copy, modify, and/or distribute this software 6 * for any purpose with or without fee is hereby granted, provided 7 * that the above copyright notice and this permission notice appear 8 * in all copies. 9 * 10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL 11 * WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED 12 * WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL 13 * THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR 14 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM 15 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, 16 * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN 17 * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 18 */ 19 20 /* This module implements the Qualcomm Atheros SPI protocol for 21 * kernel-based SPI device; it is essentially an Ethernet-to-SPI 22 * serial converter; 23 */ 24 25 #include <linux/errno.h> 26 #include <linux/etherdevice.h> 27 #include <linux/if_arp.h> 28 #include <linux/if_ether.h> 29 #include <linux/init.h> 30 #include <linux/interrupt.h> 31 #include <linux/jiffies.h> 32 #include <linux/kernel.h> 33 #include <linux/kthread.h> 34 #include <linux/module.h> 35 #include <linux/moduleparam.h> 36 #include <linux/netdevice.h> 37 #include <linux/of.h> 38 #include <linux/of_device.h> 39 #include <linux/of_net.h> 40 #include <linux/sched.h> 41 #include <linux/skbuff.h> 42 #include <linux/spi/spi.h> 43 #include <linux/types.h> 44 45 #include "qca_7k.h" 46 #include "qca_debug.h" 47 #include "qca_framing.h" 48 #include "qca_spi.h" 49 50 #define MAX_DMA_BURST_LEN 5000 51 52 /* Modules parameters */ 53 #define QCASPI_CLK_SPEED_MIN 1000000 54 #define QCASPI_CLK_SPEED_MAX 16000000 55 #define QCASPI_CLK_SPEED 8000000 56 static int qcaspi_clkspeed; 57 module_param(qcaspi_clkspeed, int, 0); 58 MODULE_PARM_DESC(qcaspi_clkspeed, "SPI bus clock speed (Hz). Use 1000000-16000000."); 59 60 #define QCASPI_BURST_LEN_MIN 1 61 #define QCASPI_BURST_LEN_MAX MAX_DMA_BURST_LEN 62 static int qcaspi_burst_len = MAX_DMA_BURST_LEN; 63 module_param(qcaspi_burst_len, int, 0); 64 MODULE_PARM_DESC(qcaspi_burst_len, "Number of data bytes per burst. Use 1-5000."); 65 66 #define QCASPI_PLUGGABLE_MIN 0 67 #define QCASPI_PLUGGABLE_MAX 1 68 static int qcaspi_pluggable = QCASPI_PLUGGABLE_MIN; 69 module_param(qcaspi_pluggable, int, 0); 70 MODULE_PARM_DESC(qcaspi_pluggable, "Pluggable SPI connection (yes/no)."); 71 72 #define QCASPI_MTU QCAFRM_ETHMAXMTU 73 #define QCASPI_TX_TIMEOUT (1 * HZ) 74 #define QCASPI_QCA7K_REBOOT_TIME_MS 1000 75 76 static void 77 start_spi_intr_handling(struct qcaspi *qca, u16 *intr_cause) 78 { 79 *intr_cause = 0; 80 81 qcaspi_write_register(qca, SPI_REG_INTR_ENABLE, 0); 82 qcaspi_read_register(qca, SPI_REG_INTR_CAUSE, intr_cause); 83 netdev_dbg(qca->net_dev, "interrupts: 0x%04x\n", *intr_cause); 84 } 85 86 static void 87 end_spi_intr_handling(struct qcaspi *qca, u16 intr_cause) 88 { 89 u16 intr_enable = (SPI_INT_CPU_ON | 90 SPI_INT_PKT_AVLBL | 91 SPI_INT_RDBUF_ERR | 92 SPI_INT_WRBUF_ERR); 93 94 qcaspi_write_register(qca, SPI_REG_INTR_CAUSE, intr_cause); 95 qcaspi_write_register(qca, SPI_REG_INTR_ENABLE, intr_enable); 96 netdev_dbg(qca->net_dev, "acking int: 0x%04x\n", intr_cause); 97 } 98 99 static u32 100 qcaspi_write_burst(struct qcaspi *qca, u8 *src, u32 len) 101 { 102 __be16 cmd; 103 struct spi_message *msg = &qca->spi_msg2; 104 struct spi_transfer *transfer = &qca->spi_xfer2[0]; 105 int ret; 106 107 cmd = cpu_to_be16(QCA7K_SPI_WRITE | QCA7K_SPI_EXTERNAL); 108 transfer->tx_buf = &cmd; 109 transfer->rx_buf = NULL; 110 transfer->len = QCASPI_CMD_LEN; 111 transfer = &qca->spi_xfer2[1]; 112 transfer->tx_buf = src; 113 transfer->rx_buf = NULL; 114 transfer->len = len; 115 116 ret = spi_sync(qca->spi_dev, msg); 117 118 if (ret || (msg->actual_length != QCASPI_CMD_LEN + len)) { 119 qcaspi_spi_error(qca); 120 return 0; 121 } 122 123 return len; 124 } 125 126 static u32 127 qcaspi_write_legacy(struct qcaspi *qca, u8 *src, u32 len) 128 { 129 struct spi_message *msg = &qca->spi_msg1; 130 struct spi_transfer *transfer = &qca->spi_xfer1; 131 int ret; 132 133 transfer->tx_buf = src; 134 transfer->rx_buf = NULL; 135 transfer->len = len; 136 137 ret = spi_sync(qca->spi_dev, msg); 138 139 if (ret || (msg->actual_length != len)) { 140 qcaspi_spi_error(qca); 141 return 0; 142 } 143 144 return len; 145 } 146 147 static u32 148 qcaspi_read_burst(struct qcaspi *qca, u8 *dst, u32 len) 149 { 150 struct spi_message *msg = &qca->spi_msg2; 151 __be16 cmd; 152 struct spi_transfer *transfer = &qca->spi_xfer2[0]; 153 int ret; 154 155 cmd = cpu_to_be16(QCA7K_SPI_READ | QCA7K_SPI_EXTERNAL); 156 transfer->tx_buf = &cmd; 157 transfer->rx_buf = NULL; 158 transfer->len = QCASPI_CMD_LEN; 159 transfer = &qca->spi_xfer2[1]; 160 transfer->tx_buf = NULL; 161 transfer->rx_buf = dst; 162 transfer->len = len; 163 164 ret = spi_sync(qca->spi_dev, msg); 165 166 if (ret || (msg->actual_length != QCASPI_CMD_LEN + len)) { 167 qcaspi_spi_error(qca); 168 return 0; 169 } 170 171 return len; 172 } 173 174 static u32 175 qcaspi_read_legacy(struct qcaspi *qca, u8 *dst, u32 len) 176 { 177 struct spi_message *msg = &qca->spi_msg1; 178 struct spi_transfer *transfer = &qca->spi_xfer1; 179 int ret; 180 181 transfer->tx_buf = NULL; 182 transfer->rx_buf = dst; 183 transfer->len = len; 184 185 ret = spi_sync(qca->spi_dev, msg); 186 187 if (ret || (msg->actual_length != len)) { 188 qcaspi_spi_error(qca); 189 return 0; 190 } 191 192 return len; 193 } 194 195 static int 196 qcaspi_tx_frame(struct qcaspi *qca, struct sk_buff *skb) 197 { 198 u32 count; 199 u32 written; 200 u32 offset; 201 u32 len; 202 203 len = skb->len; 204 205 qcaspi_write_register(qca, SPI_REG_BFR_SIZE, len); 206 if (qca->legacy_mode) 207 qcaspi_tx_cmd(qca, QCA7K_SPI_WRITE | QCA7K_SPI_EXTERNAL); 208 209 offset = 0; 210 while (len) { 211 count = len; 212 if (count > qca->burst_len) 213 count = qca->burst_len; 214 215 if (qca->legacy_mode) { 216 written = qcaspi_write_legacy(qca, 217 skb->data + offset, 218 count); 219 } else { 220 written = qcaspi_write_burst(qca, 221 skb->data + offset, 222 count); 223 } 224 225 if (written != count) 226 return -1; 227 228 offset += count; 229 len -= count; 230 } 231 232 return 0; 233 } 234 235 static int 236 qcaspi_transmit(struct qcaspi *qca) 237 { 238 struct net_device_stats *n_stats = &qca->net_dev->stats; 239 u16 available = 0; 240 u32 pkt_len; 241 u16 new_head; 242 u16 packets = 0; 243 244 if (qca->txr.skb[qca->txr.head] == NULL) 245 return 0; 246 247 qcaspi_read_register(qca, SPI_REG_WRBUF_SPC_AVA, &available); 248 249 while (qca->txr.skb[qca->txr.head]) { 250 pkt_len = qca->txr.skb[qca->txr.head]->len + QCASPI_HW_PKT_LEN; 251 252 if (available < pkt_len) { 253 if (packets == 0) 254 qca->stats.write_buf_miss++; 255 break; 256 } 257 258 if (qcaspi_tx_frame(qca, qca->txr.skb[qca->txr.head]) == -1) { 259 qca->stats.write_err++; 260 return -1; 261 } 262 263 packets++; 264 n_stats->tx_packets++; 265 n_stats->tx_bytes += qca->txr.skb[qca->txr.head]->len; 266 available -= pkt_len; 267 268 /* remove the skb from the queue */ 269 /* XXX After inconsistent lock states netif_tx_lock() 270 * has been replaced by netif_tx_lock_bh() and so on. 271 */ 272 netif_tx_lock_bh(qca->net_dev); 273 dev_kfree_skb(qca->txr.skb[qca->txr.head]); 274 qca->txr.skb[qca->txr.head] = NULL; 275 qca->txr.size -= pkt_len; 276 new_head = qca->txr.head + 1; 277 if (new_head >= qca->txr.count) 278 new_head = 0; 279 qca->txr.head = new_head; 280 if (netif_queue_stopped(qca->net_dev)) 281 netif_wake_queue(qca->net_dev); 282 netif_tx_unlock_bh(qca->net_dev); 283 } 284 285 return 0; 286 } 287 288 static int 289 qcaspi_receive(struct qcaspi *qca) 290 { 291 struct net_device *net_dev = qca->net_dev; 292 struct net_device_stats *n_stats = &net_dev->stats; 293 u16 available = 0; 294 u32 bytes_read; 295 u8 *cp; 296 297 /* Allocate rx SKB if we don't have one available. */ 298 if (!qca->rx_skb) { 299 qca->rx_skb = netdev_alloc_skb(net_dev, 300 net_dev->mtu + VLAN_ETH_HLEN); 301 if (!qca->rx_skb) { 302 netdev_dbg(net_dev, "out of RX resources\n"); 303 qca->stats.out_of_mem++; 304 return -1; 305 } 306 } 307 308 /* Read the packet size. */ 309 qcaspi_read_register(qca, SPI_REG_RDBUF_BYTE_AVA, &available); 310 netdev_dbg(net_dev, "qcaspi_receive: SPI_REG_RDBUF_BYTE_AVA: Value: %08x\n", 311 available); 312 313 if (available == 0) { 314 netdev_dbg(net_dev, "qcaspi_receive called without any data being available!\n"); 315 return -1; 316 } 317 318 qcaspi_write_register(qca, SPI_REG_BFR_SIZE, available); 319 320 if (qca->legacy_mode) 321 qcaspi_tx_cmd(qca, QCA7K_SPI_READ | QCA7K_SPI_EXTERNAL); 322 323 while (available) { 324 u32 count = available; 325 326 if (count > qca->burst_len) 327 count = qca->burst_len; 328 329 if (qca->legacy_mode) { 330 bytes_read = qcaspi_read_legacy(qca, qca->rx_buffer, 331 count); 332 } else { 333 bytes_read = qcaspi_read_burst(qca, qca->rx_buffer, 334 count); 335 } 336 337 netdev_dbg(net_dev, "available: %d, byte read: %d\n", 338 available, bytes_read); 339 340 if (bytes_read) { 341 available -= bytes_read; 342 } else { 343 qca->stats.read_err++; 344 return -1; 345 } 346 347 cp = qca->rx_buffer; 348 349 while ((bytes_read--) && (qca->rx_skb)) { 350 s32 retcode; 351 352 retcode = qcafrm_fsm_decode(&qca->frm_handle, 353 qca->rx_skb->data, 354 skb_tailroom(qca->rx_skb), 355 *cp); 356 cp++; 357 switch (retcode) { 358 case QCAFRM_GATHER: 359 case QCAFRM_NOHEAD: 360 break; 361 case QCAFRM_NOTAIL: 362 netdev_dbg(net_dev, "no RX tail\n"); 363 n_stats->rx_errors++; 364 n_stats->rx_dropped++; 365 break; 366 case QCAFRM_INVLEN: 367 netdev_dbg(net_dev, "invalid RX length\n"); 368 n_stats->rx_errors++; 369 n_stats->rx_dropped++; 370 break; 371 default: 372 qca->rx_skb->dev = qca->net_dev; 373 n_stats->rx_packets++; 374 n_stats->rx_bytes += retcode; 375 skb_put(qca->rx_skb, retcode); 376 qca->rx_skb->protocol = eth_type_trans( 377 qca->rx_skb, qca->rx_skb->dev); 378 qca->rx_skb->ip_summed = CHECKSUM_UNNECESSARY; 379 netif_rx_ni(qca->rx_skb); 380 qca->rx_skb = netdev_alloc_skb(net_dev, 381 net_dev->mtu + VLAN_ETH_HLEN); 382 if (!qca->rx_skb) { 383 netdev_dbg(net_dev, "out of RX resources\n"); 384 n_stats->rx_errors++; 385 qca->stats.out_of_mem++; 386 break; 387 } 388 } 389 } 390 } 391 392 return 0; 393 } 394 395 /* Check that tx ring stores only so much bytes 396 * that fit into the internal QCA buffer. 397 */ 398 399 static int 400 qcaspi_tx_ring_has_space(struct tx_ring *txr) 401 { 402 if (txr->skb[txr->tail]) 403 return 0; 404 405 return (txr->size + QCAFRM_ETHMAXLEN < QCASPI_HW_BUF_LEN) ? 1 : 0; 406 } 407 408 /* Flush the tx ring. This function is only safe to 409 * call from the qcaspi_spi_thread. 410 */ 411 412 static void 413 qcaspi_flush_tx_ring(struct qcaspi *qca) 414 { 415 int i; 416 417 /* XXX After inconsistent lock states netif_tx_lock() 418 * has been replaced by netif_tx_lock_bh() and so on. 419 */ 420 netif_tx_lock_bh(qca->net_dev); 421 for (i = 0; i < TX_RING_MAX_LEN; i++) { 422 if (qca->txr.skb[i]) { 423 dev_kfree_skb(qca->txr.skb[i]); 424 qca->txr.skb[i] = NULL; 425 qca->net_dev->stats.tx_dropped++; 426 } 427 } 428 qca->txr.tail = 0; 429 qca->txr.head = 0; 430 qca->txr.size = 0; 431 netif_tx_unlock_bh(qca->net_dev); 432 } 433 434 static void 435 qcaspi_qca7k_sync(struct qcaspi *qca, int event) 436 { 437 u16 signature = 0; 438 u16 spi_config; 439 u16 wrbuf_space = 0; 440 static u16 reset_count; 441 442 if (event == QCASPI_EVENT_CPUON) { 443 /* Read signature twice, if not valid 444 * go back to unknown state. 445 */ 446 qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature); 447 qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature); 448 if (signature != QCASPI_GOOD_SIGNATURE) { 449 qca->sync = QCASPI_SYNC_UNKNOWN; 450 netdev_dbg(qca->net_dev, "sync: got CPU on, but signature was invalid, restart\n"); 451 } else { 452 /* ensure that the WRBUF is empty */ 453 qcaspi_read_register(qca, SPI_REG_WRBUF_SPC_AVA, 454 &wrbuf_space); 455 if (wrbuf_space != QCASPI_HW_BUF_LEN) { 456 netdev_dbg(qca->net_dev, "sync: got CPU on, but wrbuf not empty. reset!\n"); 457 qca->sync = QCASPI_SYNC_UNKNOWN; 458 } else { 459 netdev_dbg(qca->net_dev, "sync: got CPU on, now in sync\n"); 460 qca->sync = QCASPI_SYNC_READY; 461 return; 462 } 463 } 464 } 465 466 switch (qca->sync) { 467 case QCASPI_SYNC_READY: 468 /* Read signature, if not valid go to unknown state. */ 469 qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature); 470 if (signature != QCASPI_GOOD_SIGNATURE) { 471 qca->sync = QCASPI_SYNC_UNKNOWN; 472 netdev_dbg(qca->net_dev, "sync: bad signature, restart\n"); 473 /* don't reset right away */ 474 return; 475 } 476 break; 477 case QCASPI_SYNC_UNKNOWN: 478 /* Read signature, if not valid stay in unknown state */ 479 qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature); 480 if (signature != QCASPI_GOOD_SIGNATURE) { 481 netdev_dbg(qca->net_dev, "sync: could not read signature to reset device, retry.\n"); 482 return; 483 } 484 485 /* TODO: use GPIO to reset QCA7000 in legacy mode*/ 486 netdev_dbg(qca->net_dev, "sync: resetting device.\n"); 487 qcaspi_read_register(qca, SPI_REG_SPI_CONFIG, &spi_config); 488 spi_config |= QCASPI_SLAVE_RESET_BIT; 489 qcaspi_write_register(qca, SPI_REG_SPI_CONFIG, spi_config); 490 491 qca->sync = QCASPI_SYNC_RESET; 492 qca->stats.trig_reset++; 493 reset_count = 0; 494 break; 495 case QCASPI_SYNC_RESET: 496 reset_count++; 497 netdev_dbg(qca->net_dev, "sync: waiting for CPU on, count %u.\n", 498 reset_count); 499 if (reset_count >= QCASPI_RESET_TIMEOUT) { 500 /* reset did not seem to take place, try again */ 501 qca->sync = QCASPI_SYNC_UNKNOWN; 502 qca->stats.reset_timeout++; 503 netdev_dbg(qca->net_dev, "sync: reset timeout, restarting process.\n"); 504 } 505 break; 506 } 507 } 508 509 static int 510 qcaspi_spi_thread(void *data) 511 { 512 struct qcaspi *qca = data; 513 u16 intr_cause = 0; 514 515 netdev_info(qca->net_dev, "SPI thread created\n"); 516 while (!kthread_should_stop()) { 517 set_current_state(TASK_INTERRUPTIBLE); 518 if ((qca->intr_req == qca->intr_svc) && 519 (qca->txr.skb[qca->txr.head] == NULL) && 520 (qca->sync == QCASPI_SYNC_READY)) 521 schedule(); 522 523 set_current_state(TASK_RUNNING); 524 525 netdev_dbg(qca->net_dev, "have work to do. int: %d, tx_skb: %p\n", 526 qca->intr_req - qca->intr_svc, 527 qca->txr.skb[qca->txr.head]); 528 529 qcaspi_qca7k_sync(qca, QCASPI_EVENT_UPDATE); 530 531 if (qca->sync != QCASPI_SYNC_READY) { 532 netdev_dbg(qca->net_dev, "sync: not ready %u, turn off carrier and flush\n", 533 (unsigned int)qca->sync); 534 netif_stop_queue(qca->net_dev); 535 netif_carrier_off(qca->net_dev); 536 qcaspi_flush_tx_ring(qca); 537 msleep(QCASPI_QCA7K_REBOOT_TIME_MS); 538 } 539 540 if (qca->intr_svc != qca->intr_req) { 541 qca->intr_svc = qca->intr_req; 542 start_spi_intr_handling(qca, &intr_cause); 543 544 if (intr_cause & SPI_INT_CPU_ON) { 545 qcaspi_qca7k_sync(qca, QCASPI_EVENT_CPUON); 546 547 /* not synced. */ 548 if (qca->sync != QCASPI_SYNC_READY) 549 continue; 550 551 qca->stats.device_reset++; 552 netif_wake_queue(qca->net_dev); 553 netif_carrier_on(qca->net_dev); 554 } 555 556 if (intr_cause & SPI_INT_RDBUF_ERR) { 557 /* restart sync */ 558 netdev_dbg(qca->net_dev, "===> rdbuf error!\n"); 559 qca->stats.read_buf_err++; 560 qca->sync = QCASPI_SYNC_UNKNOWN; 561 continue; 562 } 563 564 if (intr_cause & SPI_INT_WRBUF_ERR) { 565 /* restart sync */ 566 netdev_dbg(qca->net_dev, "===> wrbuf error!\n"); 567 qca->stats.write_buf_err++; 568 qca->sync = QCASPI_SYNC_UNKNOWN; 569 continue; 570 } 571 572 /* can only handle other interrupts 573 * if sync has occurred 574 */ 575 if (qca->sync == QCASPI_SYNC_READY) { 576 if (intr_cause & SPI_INT_PKT_AVLBL) 577 qcaspi_receive(qca); 578 } 579 580 end_spi_intr_handling(qca, intr_cause); 581 } 582 583 if (qca->sync == QCASPI_SYNC_READY) 584 qcaspi_transmit(qca); 585 } 586 set_current_state(TASK_RUNNING); 587 netdev_info(qca->net_dev, "SPI thread exit\n"); 588 589 return 0; 590 } 591 592 static irqreturn_t 593 qcaspi_intr_handler(int irq, void *data) 594 { 595 struct qcaspi *qca = data; 596 597 qca->intr_req++; 598 if (qca->spi_thread && 599 qca->spi_thread->state != TASK_RUNNING) 600 wake_up_process(qca->spi_thread); 601 602 return IRQ_HANDLED; 603 } 604 605 int 606 qcaspi_netdev_open(struct net_device *dev) 607 { 608 struct qcaspi *qca = netdev_priv(dev); 609 int ret = 0; 610 611 if (!qca) 612 return -EINVAL; 613 614 qca->intr_req = 1; 615 qca->intr_svc = 0; 616 qca->sync = QCASPI_SYNC_UNKNOWN; 617 qcafrm_fsm_init(&qca->frm_handle); 618 619 qca->spi_thread = kthread_run((void *)qcaspi_spi_thread, 620 qca, "%s", dev->name); 621 622 if (IS_ERR(qca->spi_thread)) { 623 netdev_err(dev, "%s: unable to start kernel thread.\n", 624 QCASPI_DRV_NAME); 625 return PTR_ERR(qca->spi_thread); 626 } 627 628 ret = request_irq(qca->spi_dev->irq, qcaspi_intr_handler, 0, 629 dev->name, qca); 630 if (ret) { 631 netdev_err(dev, "%s: unable to get IRQ %d (irqval=%d).\n", 632 QCASPI_DRV_NAME, qca->spi_dev->irq, ret); 633 kthread_stop(qca->spi_thread); 634 return ret; 635 } 636 637 netif_start_queue(qca->net_dev); 638 639 return 0; 640 } 641 642 int 643 qcaspi_netdev_close(struct net_device *dev) 644 { 645 struct qcaspi *qca = netdev_priv(dev); 646 647 netif_stop_queue(dev); 648 649 qcaspi_write_register(qca, SPI_REG_INTR_ENABLE, 0); 650 free_irq(qca->spi_dev->irq, qca); 651 652 kthread_stop(qca->spi_thread); 653 qca->spi_thread = NULL; 654 qcaspi_flush_tx_ring(qca); 655 656 return 0; 657 } 658 659 static netdev_tx_t 660 qcaspi_netdev_xmit(struct sk_buff *skb, struct net_device *dev) 661 { 662 u32 frame_len; 663 u8 *ptmp; 664 struct qcaspi *qca = netdev_priv(dev); 665 u16 new_tail; 666 struct sk_buff *tskb; 667 u8 pad_len = 0; 668 669 if (skb->len < QCAFRM_ETHMINLEN) 670 pad_len = QCAFRM_ETHMINLEN - skb->len; 671 672 if (qca->txr.skb[qca->txr.tail]) { 673 netdev_warn(qca->net_dev, "queue was unexpectedly full!\n"); 674 netif_stop_queue(qca->net_dev); 675 qca->stats.ring_full++; 676 return NETDEV_TX_BUSY; 677 } 678 679 if ((skb_headroom(skb) < QCAFRM_HEADER_LEN) || 680 (skb_tailroom(skb) < QCAFRM_FOOTER_LEN + pad_len)) { 681 tskb = skb_copy_expand(skb, QCAFRM_HEADER_LEN, 682 QCAFRM_FOOTER_LEN + pad_len, GFP_ATOMIC); 683 if (!tskb) { 684 netdev_dbg(qca->net_dev, "could not allocate tx_buff\n"); 685 qca->stats.out_of_mem++; 686 return NETDEV_TX_BUSY; 687 } 688 dev_kfree_skb(skb); 689 skb = tskb; 690 } 691 692 frame_len = skb->len + pad_len; 693 694 ptmp = skb_push(skb, QCAFRM_HEADER_LEN); 695 qcafrm_create_header(ptmp, frame_len); 696 697 if (pad_len) { 698 ptmp = skb_put(skb, pad_len); 699 memset(ptmp, 0, pad_len); 700 } 701 702 ptmp = skb_put(skb, QCAFRM_FOOTER_LEN); 703 qcafrm_create_footer(ptmp); 704 705 netdev_dbg(qca->net_dev, "Tx-ing packet: Size: 0x%08x\n", 706 skb->len); 707 708 qca->txr.size += skb->len + QCASPI_HW_PKT_LEN; 709 710 new_tail = qca->txr.tail + 1; 711 if (new_tail >= qca->txr.count) 712 new_tail = 0; 713 714 qca->txr.skb[qca->txr.tail] = skb; 715 qca->txr.tail = new_tail; 716 717 if (!qcaspi_tx_ring_has_space(&qca->txr)) { 718 netif_stop_queue(qca->net_dev); 719 qca->stats.ring_full++; 720 } 721 722 netif_trans_update(dev); 723 724 if (qca->spi_thread && 725 qca->spi_thread->state != TASK_RUNNING) 726 wake_up_process(qca->spi_thread); 727 728 return NETDEV_TX_OK; 729 } 730 731 static void 732 qcaspi_netdev_tx_timeout(struct net_device *dev) 733 { 734 struct qcaspi *qca = netdev_priv(dev); 735 736 netdev_info(qca->net_dev, "Transmit timeout at %ld, latency %ld\n", 737 jiffies, jiffies - dev_trans_start(dev)); 738 qca->net_dev->stats.tx_errors++; 739 /* Trigger tx queue flush and QCA7000 reset */ 740 qca->sync = QCASPI_SYNC_UNKNOWN; 741 } 742 743 static int 744 qcaspi_netdev_init(struct net_device *dev) 745 { 746 struct qcaspi *qca = netdev_priv(dev); 747 748 dev->mtu = QCASPI_MTU; 749 dev->type = ARPHRD_ETHER; 750 qca->clkspeed = qcaspi_clkspeed; 751 qca->burst_len = qcaspi_burst_len; 752 qca->spi_thread = NULL; 753 qca->buffer_size = (dev->mtu + VLAN_ETH_HLEN + QCAFRM_HEADER_LEN + 754 QCAFRM_FOOTER_LEN + 4) * 4; 755 756 memset(&qca->stats, 0, sizeof(struct qcaspi_stats)); 757 758 qca->rx_buffer = kmalloc(qca->buffer_size, GFP_KERNEL); 759 if (!qca->rx_buffer) 760 return -ENOBUFS; 761 762 qca->rx_skb = netdev_alloc_skb(dev, qca->net_dev->mtu + VLAN_ETH_HLEN); 763 if (!qca->rx_skb) { 764 kfree(qca->rx_buffer); 765 netdev_info(qca->net_dev, "Failed to allocate RX sk_buff.\n"); 766 return -ENOBUFS; 767 } 768 769 return 0; 770 } 771 772 static void 773 qcaspi_netdev_uninit(struct net_device *dev) 774 { 775 struct qcaspi *qca = netdev_priv(dev); 776 777 kfree(qca->rx_buffer); 778 qca->buffer_size = 0; 779 if (qca->rx_skb) 780 dev_kfree_skb(qca->rx_skb); 781 } 782 783 static const struct net_device_ops qcaspi_netdev_ops = { 784 .ndo_init = qcaspi_netdev_init, 785 .ndo_uninit = qcaspi_netdev_uninit, 786 .ndo_open = qcaspi_netdev_open, 787 .ndo_stop = qcaspi_netdev_close, 788 .ndo_start_xmit = qcaspi_netdev_xmit, 789 .ndo_set_mac_address = eth_mac_addr, 790 .ndo_tx_timeout = qcaspi_netdev_tx_timeout, 791 .ndo_validate_addr = eth_validate_addr, 792 }; 793 794 static void 795 qcaspi_netdev_setup(struct net_device *dev) 796 { 797 struct qcaspi *qca = NULL; 798 799 dev->netdev_ops = &qcaspi_netdev_ops; 800 qcaspi_set_ethtool_ops(dev); 801 dev->watchdog_timeo = QCASPI_TX_TIMEOUT; 802 dev->priv_flags &= ~IFF_TX_SKB_SHARING; 803 dev->tx_queue_len = 100; 804 805 /* MTU range: 46 - 1500 */ 806 dev->min_mtu = QCAFRM_ETHMINMTU; 807 dev->max_mtu = QCAFRM_ETHMAXMTU; 808 809 qca = netdev_priv(dev); 810 memset(qca, 0, sizeof(struct qcaspi)); 811 812 memset(&qca->spi_xfer1, 0, sizeof(struct spi_transfer)); 813 memset(&qca->spi_xfer2, 0, sizeof(struct spi_transfer) * 2); 814 815 spi_message_init(&qca->spi_msg1); 816 spi_message_add_tail(&qca->spi_xfer1, &qca->spi_msg1); 817 818 spi_message_init(&qca->spi_msg2); 819 spi_message_add_tail(&qca->spi_xfer2[0], &qca->spi_msg2); 820 spi_message_add_tail(&qca->spi_xfer2[1], &qca->spi_msg2); 821 822 memset(&qca->txr, 0, sizeof(qca->txr)); 823 qca->txr.count = TX_RING_MAX_LEN; 824 } 825 826 static const struct of_device_id qca_spi_of_match[] = { 827 { .compatible = "qca,qca7000" }, 828 { /* sentinel */ } 829 }; 830 MODULE_DEVICE_TABLE(of, qca_spi_of_match); 831 832 static int 833 qca_spi_probe(struct spi_device *spi) 834 { 835 struct qcaspi *qca = NULL; 836 struct net_device *qcaspi_devs = NULL; 837 u8 legacy_mode = 0; 838 u16 signature; 839 const char *mac; 840 841 if (!spi->dev.of_node) { 842 dev_err(&spi->dev, "Missing device tree\n"); 843 return -EINVAL; 844 } 845 846 legacy_mode = of_property_read_bool(spi->dev.of_node, 847 "qca,legacy-mode"); 848 849 if (qcaspi_clkspeed == 0) { 850 if (spi->max_speed_hz) 851 qcaspi_clkspeed = spi->max_speed_hz; 852 else 853 qcaspi_clkspeed = QCASPI_CLK_SPEED; 854 } 855 856 if ((qcaspi_clkspeed < QCASPI_CLK_SPEED_MIN) || 857 (qcaspi_clkspeed > QCASPI_CLK_SPEED_MAX)) { 858 dev_info(&spi->dev, "Invalid clkspeed: %d\n", 859 qcaspi_clkspeed); 860 return -EINVAL; 861 } 862 863 if ((qcaspi_burst_len < QCASPI_BURST_LEN_MIN) || 864 (qcaspi_burst_len > QCASPI_BURST_LEN_MAX)) { 865 dev_info(&spi->dev, "Invalid burst len: %d\n", 866 qcaspi_burst_len); 867 return -EINVAL; 868 } 869 870 if ((qcaspi_pluggable < QCASPI_PLUGGABLE_MIN) || 871 (qcaspi_pluggable > QCASPI_PLUGGABLE_MAX)) { 872 dev_info(&spi->dev, "Invalid pluggable: %d\n", 873 qcaspi_pluggable); 874 return -EINVAL; 875 } 876 877 dev_info(&spi->dev, "ver=%s, clkspeed=%d, burst_len=%d, pluggable=%d\n", 878 QCASPI_DRV_VERSION, 879 qcaspi_clkspeed, 880 qcaspi_burst_len, 881 qcaspi_pluggable); 882 883 spi->mode = SPI_MODE_3; 884 spi->max_speed_hz = qcaspi_clkspeed; 885 if (spi_setup(spi) < 0) { 886 dev_err(&spi->dev, "Unable to setup SPI device\n"); 887 return -EFAULT; 888 } 889 890 qcaspi_devs = alloc_etherdev(sizeof(struct qcaspi)); 891 if (!qcaspi_devs) 892 return -ENOMEM; 893 894 qcaspi_netdev_setup(qcaspi_devs); 895 896 qca = netdev_priv(qcaspi_devs); 897 if (!qca) { 898 free_netdev(qcaspi_devs); 899 dev_err(&spi->dev, "Fail to retrieve private structure\n"); 900 return -ENOMEM; 901 } 902 qca->net_dev = qcaspi_devs; 903 qca->spi_dev = spi; 904 qca->legacy_mode = legacy_mode; 905 906 spi_set_drvdata(spi, qcaspi_devs); 907 908 mac = of_get_mac_address(spi->dev.of_node); 909 910 if (mac) 911 ether_addr_copy(qca->net_dev->dev_addr, mac); 912 913 if (!is_valid_ether_addr(qca->net_dev->dev_addr)) { 914 eth_hw_addr_random(qca->net_dev); 915 dev_info(&spi->dev, "Using random MAC address: %pM\n", 916 qca->net_dev->dev_addr); 917 } 918 919 netif_carrier_off(qca->net_dev); 920 921 if (!qcaspi_pluggable) { 922 qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature); 923 qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature); 924 925 if (signature != QCASPI_GOOD_SIGNATURE) { 926 dev_err(&spi->dev, "Invalid signature (0x%04X)\n", 927 signature); 928 free_netdev(qcaspi_devs); 929 return -EFAULT; 930 } 931 } 932 933 if (register_netdev(qcaspi_devs)) { 934 dev_info(&spi->dev, "Unable to register net device %s\n", 935 qcaspi_devs->name); 936 free_netdev(qcaspi_devs); 937 return -EFAULT; 938 } 939 940 qcaspi_init_device_debugfs(qca); 941 942 return 0; 943 } 944 945 static int 946 qca_spi_remove(struct spi_device *spi) 947 { 948 struct net_device *qcaspi_devs = spi_get_drvdata(spi); 949 struct qcaspi *qca = netdev_priv(qcaspi_devs); 950 951 qcaspi_remove_device_debugfs(qca); 952 953 unregister_netdev(qcaspi_devs); 954 free_netdev(qcaspi_devs); 955 956 return 0; 957 } 958 959 static const struct spi_device_id qca_spi_id[] = { 960 { "qca7000", 0 }, 961 { /* sentinel */ } 962 }; 963 MODULE_DEVICE_TABLE(spi, qca_spi_id); 964 965 static struct spi_driver qca_spi_driver = { 966 .driver = { 967 .name = QCASPI_DRV_NAME, 968 .of_match_table = qca_spi_of_match, 969 }, 970 .id_table = qca_spi_id, 971 .probe = qca_spi_probe, 972 .remove = qca_spi_remove, 973 }; 974 module_spi_driver(qca_spi_driver); 975 976 MODULE_DESCRIPTION("Qualcomm Atheros SPI Driver"); 977 MODULE_AUTHOR("Qualcomm Atheros Communications"); 978 MODULE_AUTHOR("Stefan Wahren <stefan.wahren@i2se.com>"); 979 MODULE_LICENSE("Dual BSD/GPL"); 980 MODULE_VERSION(QCASPI_DRV_VERSION); 981