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_7k_common.h" 47 #include "qca_debug.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_WRITE_VERIFY_MIN 0 73 #define QCASPI_WRITE_VERIFY_MAX 3 74 static int wr_verify = QCASPI_WRITE_VERIFY_MIN; 75 module_param(wr_verify, int, 0); 76 MODULE_PARM_DESC(wr_verify, "SPI register write verify trails. Use 0-3."); 77 78 #define QCASPI_TX_TIMEOUT (1 * HZ) 79 #define QCASPI_QCA7K_REBOOT_TIME_MS 1000 80 81 static void 82 start_spi_intr_handling(struct qcaspi *qca, u16 *intr_cause) 83 { 84 *intr_cause = 0; 85 86 qcaspi_write_register(qca, SPI_REG_INTR_ENABLE, 0, wr_verify); 87 qcaspi_read_register(qca, SPI_REG_INTR_CAUSE, intr_cause); 88 netdev_dbg(qca->net_dev, "interrupts: 0x%04x\n", *intr_cause); 89 } 90 91 static void 92 end_spi_intr_handling(struct qcaspi *qca, u16 intr_cause) 93 { 94 u16 intr_enable = (SPI_INT_CPU_ON | 95 SPI_INT_PKT_AVLBL | 96 SPI_INT_RDBUF_ERR | 97 SPI_INT_WRBUF_ERR); 98 99 qcaspi_write_register(qca, SPI_REG_INTR_CAUSE, intr_cause, 0); 100 qcaspi_write_register(qca, SPI_REG_INTR_ENABLE, intr_enable, wr_verify); 101 netdev_dbg(qca->net_dev, "acking int: 0x%04x\n", intr_cause); 102 } 103 104 static u32 105 qcaspi_write_burst(struct qcaspi *qca, u8 *src, u32 len) 106 { 107 __be16 cmd; 108 struct spi_message msg; 109 struct spi_transfer transfer[2]; 110 int ret; 111 112 memset(&transfer, 0, sizeof(transfer)); 113 spi_message_init(&msg); 114 115 cmd = cpu_to_be16(QCA7K_SPI_WRITE | QCA7K_SPI_EXTERNAL); 116 transfer[0].tx_buf = &cmd; 117 transfer[0].len = QCASPI_CMD_LEN; 118 transfer[1].tx_buf = src; 119 transfer[1].len = len; 120 121 spi_message_add_tail(&transfer[0], &msg); 122 spi_message_add_tail(&transfer[1], &msg); 123 ret = spi_sync(qca->spi_dev, &msg); 124 125 if (ret || (msg.actual_length != QCASPI_CMD_LEN + len)) { 126 qcaspi_spi_error(qca); 127 return 0; 128 } 129 130 return len; 131 } 132 133 static u32 134 qcaspi_write_legacy(struct qcaspi *qca, u8 *src, u32 len) 135 { 136 struct spi_message msg; 137 struct spi_transfer transfer; 138 int ret; 139 140 memset(&transfer, 0, sizeof(transfer)); 141 spi_message_init(&msg); 142 143 transfer.tx_buf = src; 144 transfer.len = len; 145 146 spi_message_add_tail(&transfer, &msg); 147 ret = spi_sync(qca->spi_dev, &msg); 148 149 if (ret || (msg.actual_length != len)) { 150 qcaspi_spi_error(qca); 151 return 0; 152 } 153 154 return len; 155 } 156 157 static u32 158 qcaspi_read_burst(struct qcaspi *qca, u8 *dst, u32 len) 159 { 160 struct spi_message msg; 161 __be16 cmd; 162 struct spi_transfer transfer[2]; 163 int ret; 164 165 memset(&transfer, 0, sizeof(transfer)); 166 spi_message_init(&msg); 167 168 cmd = cpu_to_be16(QCA7K_SPI_READ | QCA7K_SPI_EXTERNAL); 169 transfer[0].tx_buf = &cmd; 170 transfer[0].len = QCASPI_CMD_LEN; 171 transfer[1].rx_buf = dst; 172 transfer[1].len = len; 173 174 spi_message_add_tail(&transfer[0], &msg); 175 spi_message_add_tail(&transfer[1], &msg); 176 ret = spi_sync(qca->spi_dev, &msg); 177 178 if (ret || (msg.actual_length != QCASPI_CMD_LEN + len)) { 179 qcaspi_spi_error(qca); 180 return 0; 181 } 182 183 return len; 184 } 185 186 static u32 187 qcaspi_read_legacy(struct qcaspi *qca, u8 *dst, u32 len) 188 { 189 struct spi_message msg; 190 struct spi_transfer transfer; 191 int ret; 192 193 memset(&transfer, 0, sizeof(transfer)); 194 spi_message_init(&msg); 195 196 transfer.rx_buf = dst; 197 transfer.len = len; 198 199 spi_message_add_tail(&transfer, &msg); 200 ret = spi_sync(qca->spi_dev, &msg); 201 202 if (ret || (msg.actual_length != len)) { 203 qcaspi_spi_error(qca); 204 return 0; 205 } 206 207 return len; 208 } 209 210 static int 211 qcaspi_tx_cmd(struct qcaspi *qca, u16 cmd) 212 { 213 __be16 tx_data; 214 struct spi_message msg; 215 struct spi_transfer transfer; 216 int ret; 217 218 memset(&transfer, 0, sizeof(transfer)); 219 220 spi_message_init(&msg); 221 222 tx_data = cpu_to_be16(cmd); 223 transfer.len = sizeof(cmd); 224 transfer.tx_buf = &tx_data; 225 spi_message_add_tail(&transfer, &msg); 226 227 ret = spi_sync(qca->spi_dev, &msg); 228 229 if (!ret) 230 ret = msg.status; 231 232 if (ret) 233 qcaspi_spi_error(qca); 234 235 return ret; 236 } 237 238 static int 239 qcaspi_tx_frame(struct qcaspi *qca, struct sk_buff *skb) 240 { 241 u32 count; 242 u32 written; 243 u32 offset; 244 u32 len; 245 246 len = skb->len; 247 248 qcaspi_write_register(qca, SPI_REG_BFR_SIZE, len, wr_verify); 249 if (qca->legacy_mode) 250 qcaspi_tx_cmd(qca, QCA7K_SPI_WRITE | QCA7K_SPI_EXTERNAL); 251 252 offset = 0; 253 while (len) { 254 count = len; 255 if (count > qca->burst_len) 256 count = qca->burst_len; 257 258 if (qca->legacy_mode) { 259 written = qcaspi_write_legacy(qca, 260 skb->data + offset, 261 count); 262 } else { 263 written = qcaspi_write_burst(qca, 264 skb->data + offset, 265 count); 266 } 267 268 if (written != count) 269 return -1; 270 271 offset += count; 272 len -= count; 273 } 274 275 return 0; 276 } 277 278 static int 279 qcaspi_transmit(struct qcaspi *qca) 280 { 281 struct net_device_stats *n_stats = &qca->net_dev->stats; 282 u16 available = 0; 283 u32 pkt_len; 284 u16 new_head; 285 u16 packets = 0; 286 287 if (qca->txr.skb[qca->txr.head] == NULL) 288 return 0; 289 290 qcaspi_read_register(qca, SPI_REG_WRBUF_SPC_AVA, &available); 291 292 if (available > QCASPI_HW_BUF_LEN) { 293 /* This could only happen by interferences on the SPI line. 294 * So retry later ... 295 */ 296 qca->stats.buf_avail_err++; 297 return -1; 298 } 299 300 while (qca->txr.skb[qca->txr.head]) { 301 pkt_len = qca->txr.skb[qca->txr.head]->len + QCASPI_HW_PKT_LEN; 302 303 if (available < pkt_len) { 304 if (packets == 0) 305 qca->stats.write_buf_miss++; 306 break; 307 } 308 309 if (qcaspi_tx_frame(qca, qca->txr.skb[qca->txr.head]) == -1) { 310 qca->stats.write_err++; 311 return -1; 312 } 313 314 packets++; 315 n_stats->tx_packets++; 316 n_stats->tx_bytes += qca->txr.skb[qca->txr.head]->len; 317 available -= pkt_len; 318 319 /* remove the skb from the queue */ 320 /* XXX After inconsistent lock states netif_tx_lock() 321 * has been replaced by netif_tx_lock_bh() and so on. 322 */ 323 netif_tx_lock_bh(qca->net_dev); 324 dev_kfree_skb(qca->txr.skb[qca->txr.head]); 325 qca->txr.skb[qca->txr.head] = NULL; 326 qca->txr.size -= pkt_len; 327 new_head = qca->txr.head + 1; 328 if (new_head >= qca->txr.count) 329 new_head = 0; 330 qca->txr.head = new_head; 331 if (netif_queue_stopped(qca->net_dev)) 332 netif_wake_queue(qca->net_dev); 333 netif_tx_unlock_bh(qca->net_dev); 334 } 335 336 return 0; 337 } 338 339 static int 340 qcaspi_receive(struct qcaspi *qca) 341 { 342 struct net_device *net_dev = qca->net_dev; 343 struct net_device_stats *n_stats = &net_dev->stats; 344 u16 available = 0; 345 u32 bytes_read; 346 u8 *cp; 347 348 /* Allocate rx SKB if we don't have one available. */ 349 if (!qca->rx_skb) { 350 qca->rx_skb = netdev_alloc_skb_ip_align(net_dev, 351 net_dev->mtu + 352 VLAN_ETH_HLEN); 353 if (!qca->rx_skb) { 354 netdev_dbg(net_dev, "out of RX resources\n"); 355 qca->stats.out_of_mem++; 356 return -1; 357 } 358 } 359 360 /* Read the packet size. */ 361 qcaspi_read_register(qca, SPI_REG_RDBUF_BYTE_AVA, &available); 362 363 netdev_dbg(net_dev, "qcaspi_receive: SPI_REG_RDBUF_BYTE_AVA: Value: %08x\n", 364 available); 365 366 if (available > QCASPI_HW_BUF_LEN + QCASPI_HW_PKT_LEN) { 367 /* This could only happen by interferences on the SPI line. 368 * So retry later ... 369 */ 370 qca->stats.buf_avail_err++; 371 return -1; 372 } else if (available == 0) { 373 netdev_dbg(net_dev, "qcaspi_receive called without any data being available!\n"); 374 return -1; 375 } 376 377 qcaspi_write_register(qca, SPI_REG_BFR_SIZE, available, wr_verify); 378 379 if (qca->legacy_mode) 380 qcaspi_tx_cmd(qca, QCA7K_SPI_READ | QCA7K_SPI_EXTERNAL); 381 382 while (available) { 383 u32 count = available; 384 385 if (count > qca->burst_len) 386 count = qca->burst_len; 387 388 if (qca->legacy_mode) { 389 bytes_read = qcaspi_read_legacy(qca, qca->rx_buffer, 390 count); 391 } else { 392 bytes_read = qcaspi_read_burst(qca, qca->rx_buffer, 393 count); 394 } 395 396 netdev_dbg(net_dev, "available: %d, byte read: %d\n", 397 available, bytes_read); 398 399 if (bytes_read) { 400 available -= bytes_read; 401 } else { 402 qca->stats.read_err++; 403 return -1; 404 } 405 406 cp = qca->rx_buffer; 407 408 while ((bytes_read--) && (qca->rx_skb)) { 409 s32 retcode; 410 411 retcode = qcafrm_fsm_decode(&qca->frm_handle, 412 qca->rx_skb->data, 413 skb_tailroom(qca->rx_skb), 414 *cp); 415 cp++; 416 switch (retcode) { 417 case QCAFRM_GATHER: 418 case QCAFRM_NOHEAD: 419 break; 420 case QCAFRM_NOTAIL: 421 netdev_dbg(net_dev, "no RX tail\n"); 422 n_stats->rx_errors++; 423 n_stats->rx_dropped++; 424 break; 425 case QCAFRM_INVLEN: 426 netdev_dbg(net_dev, "invalid RX length\n"); 427 n_stats->rx_errors++; 428 n_stats->rx_dropped++; 429 break; 430 default: 431 qca->rx_skb->dev = qca->net_dev; 432 n_stats->rx_packets++; 433 n_stats->rx_bytes += retcode; 434 skb_put(qca->rx_skb, retcode); 435 qca->rx_skb->protocol = eth_type_trans( 436 qca->rx_skb, qca->rx_skb->dev); 437 skb_checksum_none_assert(qca->rx_skb); 438 netif_rx_ni(qca->rx_skb); 439 qca->rx_skb = netdev_alloc_skb_ip_align(net_dev, 440 net_dev->mtu + VLAN_ETH_HLEN); 441 if (!qca->rx_skb) { 442 netdev_dbg(net_dev, "out of RX resources\n"); 443 n_stats->rx_errors++; 444 qca->stats.out_of_mem++; 445 break; 446 } 447 } 448 } 449 } 450 451 return 0; 452 } 453 454 /* Check that tx ring stores only so much bytes 455 * that fit into the internal QCA buffer. 456 */ 457 458 static int 459 qcaspi_tx_ring_has_space(struct tx_ring *txr) 460 { 461 if (txr->skb[txr->tail]) 462 return 0; 463 464 return (txr->size + QCAFRM_MAX_LEN < QCASPI_HW_BUF_LEN) ? 1 : 0; 465 } 466 467 /* Flush the tx ring. This function is only safe to 468 * call from the qcaspi_spi_thread. 469 */ 470 471 static void 472 qcaspi_flush_tx_ring(struct qcaspi *qca) 473 { 474 int i; 475 476 /* XXX After inconsistent lock states netif_tx_lock() 477 * has been replaced by netif_tx_lock_bh() and so on. 478 */ 479 netif_tx_lock_bh(qca->net_dev); 480 for (i = 0; i < TX_RING_MAX_LEN; i++) { 481 if (qca->txr.skb[i]) { 482 dev_kfree_skb(qca->txr.skb[i]); 483 qca->txr.skb[i] = NULL; 484 qca->net_dev->stats.tx_dropped++; 485 } 486 } 487 qca->txr.tail = 0; 488 qca->txr.head = 0; 489 qca->txr.size = 0; 490 netif_tx_unlock_bh(qca->net_dev); 491 } 492 493 static void 494 qcaspi_qca7k_sync(struct qcaspi *qca, int event) 495 { 496 u16 signature = 0; 497 u16 spi_config; 498 u16 wrbuf_space = 0; 499 500 if (event == QCASPI_EVENT_CPUON) { 501 /* Read signature twice, if not valid 502 * go back to unknown state. 503 */ 504 qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature); 505 qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature); 506 if (signature != QCASPI_GOOD_SIGNATURE) { 507 if (qca->sync == QCASPI_SYNC_READY) 508 qca->stats.bad_signature++; 509 510 qca->sync = QCASPI_SYNC_UNKNOWN; 511 netdev_dbg(qca->net_dev, "sync: got CPU on, but signature was invalid, restart\n"); 512 return; 513 } else { 514 /* ensure that the WRBUF is empty */ 515 qcaspi_read_register(qca, SPI_REG_WRBUF_SPC_AVA, 516 &wrbuf_space); 517 if (wrbuf_space != QCASPI_HW_BUF_LEN) { 518 netdev_dbg(qca->net_dev, "sync: got CPU on, but wrbuf not empty. reset!\n"); 519 qca->sync = QCASPI_SYNC_UNKNOWN; 520 } else { 521 netdev_dbg(qca->net_dev, "sync: got CPU on, now in sync\n"); 522 qca->sync = QCASPI_SYNC_READY; 523 return; 524 } 525 } 526 } 527 528 switch (qca->sync) { 529 case QCASPI_SYNC_READY: 530 /* Check signature twice, if not valid go to unknown state. */ 531 qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature); 532 if (signature != QCASPI_GOOD_SIGNATURE) 533 qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature); 534 535 if (signature != QCASPI_GOOD_SIGNATURE) { 536 qca->sync = QCASPI_SYNC_UNKNOWN; 537 qca->stats.bad_signature++; 538 netdev_dbg(qca->net_dev, "sync: bad signature, restart\n"); 539 /* don't reset right away */ 540 return; 541 } 542 break; 543 case QCASPI_SYNC_UNKNOWN: 544 /* Read signature, if not valid stay in unknown state */ 545 qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature); 546 if (signature != QCASPI_GOOD_SIGNATURE) { 547 netdev_dbg(qca->net_dev, "sync: could not read signature to reset device, retry.\n"); 548 return; 549 } 550 551 /* TODO: use GPIO to reset QCA7000 in legacy mode*/ 552 netdev_dbg(qca->net_dev, "sync: resetting device.\n"); 553 qcaspi_read_register(qca, SPI_REG_SPI_CONFIG, &spi_config); 554 spi_config |= QCASPI_SLAVE_RESET_BIT; 555 qcaspi_write_register(qca, SPI_REG_SPI_CONFIG, spi_config, 0); 556 557 qca->sync = QCASPI_SYNC_RESET; 558 qca->stats.trig_reset++; 559 qca->reset_count = 0; 560 break; 561 case QCASPI_SYNC_RESET: 562 qca->reset_count++; 563 netdev_dbg(qca->net_dev, "sync: waiting for CPU on, count %u.\n", 564 qca->reset_count); 565 if (qca->reset_count >= QCASPI_RESET_TIMEOUT) { 566 /* reset did not seem to take place, try again */ 567 qca->sync = QCASPI_SYNC_UNKNOWN; 568 qca->stats.reset_timeout++; 569 netdev_dbg(qca->net_dev, "sync: reset timeout, restarting process.\n"); 570 } 571 break; 572 } 573 } 574 575 static int 576 qcaspi_spi_thread(void *data) 577 { 578 struct qcaspi *qca = data; 579 u16 intr_cause = 0; 580 581 netdev_info(qca->net_dev, "SPI thread created\n"); 582 while (!kthread_should_stop()) { 583 set_current_state(TASK_INTERRUPTIBLE); 584 if ((qca->intr_req == qca->intr_svc) && 585 (qca->txr.skb[qca->txr.head] == NULL) && 586 (qca->sync == QCASPI_SYNC_READY)) 587 schedule(); 588 589 set_current_state(TASK_RUNNING); 590 591 netdev_dbg(qca->net_dev, "have work to do. int: %d, tx_skb: %p\n", 592 qca->intr_req - qca->intr_svc, 593 qca->txr.skb[qca->txr.head]); 594 595 qcaspi_qca7k_sync(qca, QCASPI_EVENT_UPDATE); 596 597 if (qca->sync != QCASPI_SYNC_READY) { 598 netdev_dbg(qca->net_dev, "sync: not ready %u, turn off carrier and flush\n", 599 (unsigned int)qca->sync); 600 netif_stop_queue(qca->net_dev); 601 netif_carrier_off(qca->net_dev); 602 qcaspi_flush_tx_ring(qca); 603 msleep(QCASPI_QCA7K_REBOOT_TIME_MS); 604 } 605 606 if (qca->intr_svc != qca->intr_req) { 607 qca->intr_svc = qca->intr_req; 608 start_spi_intr_handling(qca, &intr_cause); 609 610 if (intr_cause & SPI_INT_CPU_ON) { 611 qcaspi_qca7k_sync(qca, QCASPI_EVENT_CPUON); 612 613 /* not synced. */ 614 if (qca->sync != QCASPI_SYNC_READY) 615 continue; 616 617 qca->stats.device_reset++; 618 netif_wake_queue(qca->net_dev); 619 netif_carrier_on(qca->net_dev); 620 } 621 622 if (intr_cause & SPI_INT_RDBUF_ERR) { 623 /* restart sync */ 624 netdev_dbg(qca->net_dev, "===> rdbuf error!\n"); 625 qca->stats.read_buf_err++; 626 qca->sync = QCASPI_SYNC_UNKNOWN; 627 continue; 628 } 629 630 if (intr_cause & SPI_INT_WRBUF_ERR) { 631 /* restart sync */ 632 netdev_dbg(qca->net_dev, "===> wrbuf error!\n"); 633 qca->stats.write_buf_err++; 634 qca->sync = QCASPI_SYNC_UNKNOWN; 635 continue; 636 } 637 638 /* can only handle other interrupts 639 * if sync has occurred 640 */ 641 if (qca->sync == QCASPI_SYNC_READY) { 642 if (intr_cause & SPI_INT_PKT_AVLBL) 643 qcaspi_receive(qca); 644 } 645 646 end_spi_intr_handling(qca, intr_cause); 647 } 648 649 if (qca->sync == QCASPI_SYNC_READY) 650 qcaspi_transmit(qca); 651 } 652 set_current_state(TASK_RUNNING); 653 netdev_info(qca->net_dev, "SPI thread exit\n"); 654 655 return 0; 656 } 657 658 static irqreturn_t 659 qcaspi_intr_handler(int irq, void *data) 660 { 661 struct qcaspi *qca = data; 662 663 qca->intr_req++; 664 if (qca->spi_thread) 665 wake_up_process(qca->spi_thread); 666 667 return IRQ_HANDLED; 668 } 669 670 static int 671 qcaspi_netdev_open(struct net_device *dev) 672 { 673 struct qcaspi *qca = netdev_priv(dev); 674 int ret = 0; 675 676 if (!qca) 677 return -EINVAL; 678 679 qca->intr_req = 1; 680 qca->intr_svc = 0; 681 qca->sync = QCASPI_SYNC_UNKNOWN; 682 qcafrm_fsm_init_spi(&qca->frm_handle); 683 684 qca->spi_thread = kthread_run((void *)qcaspi_spi_thread, 685 qca, "%s", dev->name); 686 687 if (IS_ERR(qca->spi_thread)) { 688 netdev_err(dev, "%s: unable to start kernel thread.\n", 689 QCASPI_DRV_NAME); 690 return PTR_ERR(qca->spi_thread); 691 } 692 693 ret = request_irq(qca->spi_dev->irq, qcaspi_intr_handler, 0, 694 dev->name, qca); 695 if (ret) { 696 netdev_err(dev, "%s: unable to get IRQ %d (irqval=%d).\n", 697 QCASPI_DRV_NAME, qca->spi_dev->irq, ret); 698 kthread_stop(qca->spi_thread); 699 return ret; 700 } 701 702 /* SPI thread takes care of TX queue */ 703 704 return 0; 705 } 706 707 static int 708 qcaspi_netdev_close(struct net_device *dev) 709 { 710 struct qcaspi *qca = netdev_priv(dev); 711 712 netif_stop_queue(dev); 713 714 qcaspi_write_register(qca, SPI_REG_INTR_ENABLE, 0, wr_verify); 715 free_irq(qca->spi_dev->irq, qca); 716 717 kthread_stop(qca->spi_thread); 718 qca->spi_thread = NULL; 719 qcaspi_flush_tx_ring(qca); 720 721 return 0; 722 } 723 724 static netdev_tx_t 725 qcaspi_netdev_xmit(struct sk_buff *skb, struct net_device *dev) 726 { 727 u32 frame_len; 728 u8 *ptmp; 729 struct qcaspi *qca = netdev_priv(dev); 730 u16 new_tail; 731 struct sk_buff *tskb; 732 u8 pad_len = 0; 733 734 if (skb->len < QCAFRM_MIN_LEN) 735 pad_len = QCAFRM_MIN_LEN - skb->len; 736 737 if (qca->txr.skb[qca->txr.tail]) { 738 netdev_warn(qca->net_dev, "queue was unexpectedly full!\n"); 739 netif_stop_queue(qca->net_dev); 740 qca->stats.ring_full++; 741 return NETDEV_TX_BUSY; 742 } 743 744 if ((skb_headroom(skb) < QCAFRM_HEADER_LEN) || 745 (skb_tailroom(skb) < QCAFRM_FOOTER_LEN + pad_len)) { 746 tskb = skb_copy_expand(skb, QCAFRM_HEADER_LEN, 747 QCAFRM_FOOTER_LEN + pad_len, GFP_ATOMIC); 748 if (!tskb) { 749 qca->stats.out_of_mem++; 750 return NETDEV_TX_BUSY; 751 } 752 dev_kfree_skb(skb); 753 skb = tskb; 754 } 755 756 frame_len = skb->len + pad_len; 757 758 ptmp = skb_push(skb, QCAFRM_HEADER_LEN); 759 qcafrm_create_header(ptmp, frame_len); 760 761 if (pad_len) { 762 ptmp = skb_put_zero(skb, pad_len); 763 } 764 765 ptmp = skb_put(skb, QCAFRM_FOOTER_LEN); 766 qcafrm_create_footer(ptmp); 767 768 netdev_dbg(qca->net_dev, "Tx-ing packet: Size: 0x%08x\n", 769 skb->len); 770 771 qca->txr.size += skb->len + QCASPI_HW_PKT_LEN; 772 773 new_tail = qca->txr.tail + 1; 774 if (new_tail >= qca->txr.count) 775 new_tail = 0; 776 777 qca->txr.skb[qca->txr.tail] = skb; 778 qca->txr.tail = new_tail; 779 780 if (!qcaspi_tx_ring_has_space(&qca->txr)) { 781 netif_stop_queue(qca->net_dev); 782 qca->stats.ring_full++; 783 } 784 785 netif_trans_update(dev); 786 787 if (qca->spi_thread) 788 wake_up_process(qca->spi_thread); 789 790 return NETDEV_TX_OK; 791 } 792 793 static void 794 qcaspi_netdev_tx_timeout(struct net_device *dev, unsigned int txqueue) 795 { 796 struct qcaspi *qca = netdev_priv(dev); 797 798 netdev_info(qca->net_dev, "Transmit timeout at %ld, latency %ld\n", 799 jiffies, jiffies - dev_trans_start(dev)); 800 qca->net_dev->stats.tx_errors++; 801 /* Trigger tx queue flush and QCA7000 reset */ 802 qca->sync = QCASPI_SYNC_UNKNOWN; 803 804 if (qca->spi_thread) 805 wake_up_process(qca->spi_thread); 806 } 807 808 static int 809 qcaspi_netdev_init(struct net_device *dev) 810 { 811 struct qcaspi *qca = netdev_priv(dev); 812 813 dev->mtu = QCAFRM_MAX_MTU; 814 dev->type = ARPHRD_ETHER; 815 qca->clkspeed = qcaspi_clkspeed; 816 qca->burst_len = qcaspi_burst_len; 817 qca->spi_thread = NULL; 818 qca->buffer_size = (dev->mtu + VLAN_ETH_HLEN + QCAFRM_HEADER_LEN + 819 QCAFRM_FOOTER_LEN + 4) * 4; 820 821 memset(&qca->stats, 0, sizeof(struct qcaspi_stats)); 822 823 qca->rx_buffer = kmalloc(qca->buffer_size, GFP_KERNEL); 824 if (!qca->rx_buffer) 825 return -ENOBUFS; 826 827 qca->rx_skb = netdev_alloc_skb_ip_align(dev, qca->net_dev->mtu + 828 VLAN_ETH_HLEN); 829 if (!qca->rx_skb) { 830 kfree(qca->rx_buffer); 831 netdev_info(qca->net_dev, "Failed to allocate RX sk_buff.\n"); 832 return -ENOBUFS; 833 } 834 835 return 0; 836 } 837 838 static void 839 qcaspi_netdev_uninit(struct net_device *dev) 840 { 841 struct qcaspi *qca = netdev_priv(dev); 842 843 kfree(qca->rx_buffer); 844 qca->buffer_size = 0; 845 dev_kfree_skb(qca->rx_skb); 846 } 847 848 static const struct net_device_ops qcaspi_netdev_ops = { 849 .ndo_init = qcaspi_netdev_init, 850 .ndo_uninit = qcaspi_netdev_uninit, 851 .ndo_open = qcaspi_netdev_open, 852 .ndo_stop = qcaspi_netdev_close, 853 .ndo_start_xmit = qcaspi_netdev_xmit, 854 .ndo_set_mac_address = eth_mac_addr, 855 .ndo_tx_timeout = qcaspi_netdev_tx_timeout, 856 .ndo_validate_addr = eth_validate_addr, 857 }; 858 859 static void 860 qcaspi_netdev_setup(struct net_device *dev) 861 { 862 struct qcaspi *qca = NULL; 863 864 dev->netdev_ops = &qcaspi_netdev_ops; 865 qcaspi_set_ethtool_ops(dev); 866 dev->watchdog_timeo = QCASPI_TX_TIMEOUT; 867 dev->priv_flags &= ~IFF_TX_SKB_SHARING; 868 dev->tx_queue_len = 100; 869 870 /* MTU range: 46 - 1500 */ 871 dev->min_mtu = QCAFRM_MIN_MTU; 872 dev->max_mtu = QCAFRM_MAX_MTU; 873 874 qca = netdev_priv(dev); 875 memset(qca, 0, sizeof(struct qcaspi)); 876 877 memset(&qca->txr, 0, sizeof(qca->txr)); 878 qca->txr.count = TX_RING_MAX_LEN; 879 } 880 881 static const struct of_device_id qca_spi_of_match[] = { 882 { .compatible = "qca,qca7000" }, 883 { /* sentinel */ } 884 }; 885 MODULE_DEVICE_TABLE(of, qca_spi_of_match); 886 887 static int 888 qca_spi_probe(struct spi_device *spi) 889 { 890 struct qcaspi *qca = NULL; 891 struct net_device *qcaspi_devs = NULL; 892 u8 legacy_mode = 0; 893 u16 signature; 894 int ret; 895 896 if (!spi->dev.of_node) { 897 dev_err(&spi->dev, "Missing device tree\n"); 898 return -EINVAL; 899 } 900 901 legacy_mode = of_property_read_bool(spi->dev.of_node, 902 "qca,legacy-mode"); 903 904 if (qcaspi_clkspeed == 0) { 905 if (spi->max_speed_hz) 906 qcaspi_clkspeed = spi->max_speed_hz; 907 else 908 qcaspi_clkspeed = QCASPI_CLK_SPEED; 909 } 910 911 if ((qcaspi_clkspeed < QCASPI_CLK_SPEED_MIN) || 912 (qcaspi_clkspeed > QCASPI_CLK_SPEED_MAX)) { 913 dev_err(&spi->dev, "Invalid clkspeed: %d\n", 914 qcaspi_clkspeed); 915 return -EINVAL; 916 } 917 918 if ((qcaspi_burst_len < QCASPI_BURST_LEN_MIN) || 919 (qcaspi_burst_len > QCASPI_BURST_LEN_MAX)) { 920 dev_err(&spi->dev, "Invalid burst len: %d\n", 921 qcaspi_burst_len); 922 return -EINVAL; 923 } 924 925 if ((qcaspi_pluggable < QCASPI_PLUGGABLE_MIN) || 926 (qcaspi_pluggable > QCASPI_PLUGGABLE_MAX)) { 927 dev_err(&spi->dev, "Invalid pluggable: %d\n", 928 qcaspi_pluggable); 929 return -EINVAL; 930 } 931 932 if (wr_verify < QCASPI_WRITE_VERIFY_MIN || 933 wr_verify > QCASPI_WRITE_VERIFY_MAX) { 934 dev_err(&spi->dev, "Invalid write verify: %d\n", 935 wr_verify); 936 return -EINVAL; 937 } 938 939 dev_info(&spi->dev, "ver=%s, clkspeed=%d, burst_len=%d, pluggable=%d\n", 940 QCASPI_DRV_VERSION, 941 qcaspi_clkspeed, 942 qcaspi_burst_len, 943 qcaspi_pluggable); 944 945 spi->mode = SPI_MODE_3; 946 spi->max_speed_hz = qcaspi_clkspeed; 947 if (spi_setup(spi) < 0) { 948 dev_err(&spi->dev, "Unable to setup SPI device\n"); 949 return -EFAULT; 950 } 951 952 qcaspi_devs = alloc_etherdev(sizeof(struct qcaspi)); 953 if (!qcaspi_devs) 954 return -ENOMEM; 955 956 qcaspi_netdev_setup(qcaspi_devs); 957 SET_NETDEV_DEV(qcaspi_devs, &spi->dev); 958 959 qca = netdev_priv(qcaspi_devs); 960 if (!qca) { 961 free_netdev(qcaspi_devs); 962 dev_err(&spi->dev, "Fail to retrieve private structure\n"); 963 return -ENOMEM; 964 } 965 qca->net_dev = qcaspi_devs; 966 qca->spi_dev = spi; 967 qca->legacy_mode = legacy_mode; 968 969 spi_set_drvdata(spi, qcaspi_devs); 970 971 ret = of_get_ethdev_address(spi->dev.of_node, qca->net_dev); 972 if (ret) { 973 eth_hw_addr_random(qca->net_dev); 974 dev_info(&spi->dev, "Using random MAC address: %pM\n", 975 qca->net_dev->dev_addr); 976 } 977 978 netif_carrier_off(qca->net_dev); 979 980 if (!qcaspi_pluggable) { 981 qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature); 982 qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature); 983 984 if (signature != QCASPI_GOOD_SIGNATURE) { 985 dev_err(&spi->dev, "Invalid signature (0x%04X)\n", 986 signature); 987 free_netdev(qcaspi_devs); 988 return -EFAULT; 989 } 990 } 991 992 if (register_netdev(qcaspi_devs)) { 993 dev_err(&spi->dev, "Unable to register net device %s\n", 994 qcaspi_devs->name); 995 free_netdev(qcaspi_devs); 996 return -EFAULT; 997 } 998 999 qcaspi_init_device_debugfs(qca); 1000 1001 return 0; 1002 } 1003 1004 static int 1005 qca_spi_remove(struct spi_device *spi) 1006 { 1007 struct net_device *qcaspi_devs = spi_get_drvdata(spi); 1008 struct qcaspi *qca = netdev_priv(qcaspi_devs); 1009 1010 qcaspi_remove_device_debugfs(qca); 1011 1012 unregister_netdev(qcaspi_devs); 1013 free_netdev(qcaspi_devs); 1014 1015 return 0; 1016 } 1017 1018 static const struct spi_device_id qca_spi_id[] = { 1019 { "qca7000", 0 }, 1020 { /* sentinel */ } 1021 }; 1022 MODULE_DEVICE_TABLE(spi, qca_spi_id); 1023 1024 static struct spi_driver qca_spi_driver = { 1025 .driver = { 1026 .name = QCASPI_DRV_NAME, 1027 .of_match_table = qca_spi_of_match, 1028 }, 1029 .id_table = qca_spi_id, 1030 .probe = qca_spi_probe, 1031 .remove = qca_spi_remove, 1032 }; 1033 module_spi_driver(qca_spi_driver); 1034 1035 MODULE_DESCRIPTION("Qualcomm Atheros QCA7000 SPI Driver"); 1036 MODULE_AUTHOR("Qualcomm Atheros Communications"); 1037 MODULE_AUTHOR("Stefan Wahren <stefan.wahren@i2se.com>"); 1038 MODULE_LICENSE("Dual BSD/GPL"); 1039 MODULE_VERSION(QCASPI_DRV_VERSION); 1040