1 // SPDX-License-Identifier: GPL-2.0 OR BSD-2-Clause 2 /* 3 * Copyright (c) 2011, 2012, Qualcomm Atheros Communications Inc. 4 * Copyright (c) 2014, I2SE GmbH 5 */ 6 7 /* This module implements the Qualcomm Atheros SPI protocol for 8 * kernel-based SPI device; it is essentially an Ethernet-to-SPI 9 * serial converter; 10 */ 11 12 #include <linux/errno.h> 13 #include <linux/etherdevice.h> 14 #include <linux/if_arp.h> 15 #include <linux/if_ether.h> 16 #include <linux/init.h> 17 #include <linux/interrupt.h> 18 #include <linux/jiffies.h> 19 #include <linux/kernel.h> 20 #include <linux/kthread.h> 21 #include <linux/module.h> 22 #include <linux/moduleparam.h> 23 #include <linux/netdevice.h> 24 #include <linux/of.h> 25 #include <linux/of_net.h> 26 #include <linux/sched.h> 27 #include <linux/skbuff.h> 28 #include <linux/spi/spi.h> 29 #include <linux/types.h> 30 31 #include "qca_7k.h" 32 #include "qca_7k_common.h" 33 #include "qca_debug.h" 34 #include "qca_spi.h" 35 36 #define MAX_DMA_BURST_LEN 5000 37 38 /* Modules parameters */ 39 #define QCASPI_CLK_SPEED_MIN 1000000 40 #define QCASPI_CLK_SPEED_MAX 16000000 41 #define QCASPI_CLK_SPEED 8000000 42 static int qcaspi_clkspeed; 43 module_param(qcaspi_clkspeed, int, 0); 44 MODULE_PARM_DESC(qcaspi_clkspeed, "SPI bus clock speed (Hz). Use 1000000-16000000."); 45 46 #define QCASPI_BURST_LEN_MIN 1 47 #define QCASPI_BURST_LEN_MAX MAX_DMA_BURST_LEN 48 static int qcaspi_burst_len = MAX_DMA_BURST_LEN; 49 module_param(qcaspi_burst_len, int, 0); 50 MODULE_PARM_DESC(qcaspi_burst_len, "Number of data bytes per burst. Use 1-5000."); 51 52 #define QCASPI_PLUGGABLE_MIN 0 53 #define QCASPI_PLUGGABLE_MAX 1 54 static int qcaspi_pluggable = QCASPI_PLUGGABLE_MIN; 55 module_param(qcaspi_pluggable, int, 0); 56 MODULE_PARM_DESC(qcaspi_pluggable, "Pluggable SPI connection (yes/no)."); 57 58 #define QCASPI_WRITE_VERIFY_MIN 0 59 #define QCASPI_WRITE_VERIFY_MAX 3 60 static int wr_verify = QCASPI_WRITE_VERIFY_MIN; 61 module_param(wr_verify, int, 0); 62 MODULE_PARM_DESC(wr_verify, "SPI register write verify trails. Use 0-3."); 63 64 #define QCASPI_TX_TIMEOUT (1 * HZ) 65 #define QCASPI_QCA7K_REBOOT_TIME_MS 1000 66 67 static void 68 start_spi_intr_handling(struct qcaspi *qca, u16 *intr_cause) 69 { 70 *intr_cause = 0; 71 72 qcaspi_write_register(qca, SPI_REG_INTR_ENABLE, 0, wr_verify); 73 qcaspi_read_register(qca, SPI_REG_INTR_CAUSE, intr_cause); 74 netdev_dbg(qca->net_dev, "interrupts: 0x%04x\n", *intr_cause); 75 } 76 77 static void 78 end_spi_intr_handling(struct qcaspi *qca, u16 intr_cause) 79 { 80 u16 intr_enable = (SPI_INT_CPU_ON | 81 SPI_INT_PKT_AVLBL | 82 SPI_INT_RDBUF_ERR | 83 SPI_INT_WRBUF_ERR); 84 85 qcaspi_write_register(qca, SPI_REG_INTR_CAUSE, intr_cause, 0); 86 qcaspi_write_register(qca, SPI_REG_INTR_ENABLE, intr_enable, wr_verify); 87 netdev_dbg(qca->net_dev, "acking int: 0x%04x\n", intr_cause); 88 } 89 90 static u32 91 qcaspi_write_burst(struct qcaspi *qca, u8 *src, u32 len) 92 { 93 __be16 cmd; 94 struct spi_message msg; 95 struct spi_transfer transfer[2]; 96 int ret; 97 98 memset(&transfer, 0, sizeof(transfer)); 99 spi_message_init(&msg); 100 101 cmd = cpu_to_be16(QCA7K_SPI_WRITE | QCA7K_SPI_EXTERNAL); 102 transfer[0].tx_buf = &cmd; 103 transfer[0].len = QCASPI_CMD_LEN; 104 transfer[1].tx_buf = src; 105 transfer[1].len = len; 106 107 spi_message_add_tail(&transfer[0], &msg); 108 spi_message_add_tail(&transfer[1], &msg); 109 ret = spi_sync(qca->spi_dev, &msg); 110 111 if (ret || (msg.actual_length != QCASPI_CMD_LEN + len)) { 112 qcaspi_spi_error(qca); 113 return 0; 114 } 115 116 return len; 117 } 118 119 static u32 120 qcaspi_write_legacy(struct qcaspi *qca, u8 *src, u32 len) 121 { 122 struct spi_message msg; 123 struct spi_transfer transfer; 124 int ret; 125 126 memset(&transfer, 0, sizeof(transfer)); 127 spi_message_init(&msg); 128 129 transfer.tx_buf = src; 130 transfer.len = len; 131 132 spi_message_add_tail(&transfer, &msg); 133 ret = spi_sync(qca->spi_dev, &msg); 134 135 if (ret || (msg.actual_length != len)) { 136 qcaspi_spi_error(qca); 137 return 0; 138 } 139 140 return len; 141 } 142 143 static u32 144 qcaspi_read_burst(struct qcaspi *qca, u8 *dst, u32 len) 145 { 146 struct spi_message msg; 147 __be16 cmd; 148 struct spi_transfer transfer[2]; 149 int ret; 150 151 memset(&transfer, 0, sizeof(transfer)); 152 spi_message_init(&msg); 153 154 cmd = cpu_to_be16(QCA7K_SPI_READ | QCA7K_SPI_EXTERNAL); 155 transfer[0].tx_buf = &cmd; 156 transfer[0].len = QCASPI_CMD_LEN; 157 transfer[1].rx_buf = dst; 158 transfer[1].len = len; 159 160 spi_message_add_tail(&transfer[0], &msg); 161 spi_message_add_tail(&transfer[1], &msg); 162 ret = spi_sync(qca->spi_dev, &msg); 163 164 if (ret || (msg.actual_length != QCASPI_CMD_LEN + len)) { 165 qcaspi_spi_error(qca); 166 return 0; 167 } 168 169 return len; 170 } 171 172 static u32 173 qcaspi_read_legacy(struct qcaspi *qca, u8 *dst, u32 len) 174 { 175 struct spi_message msg; 176 struct spi_transfer transfer; 177 int ret; 178 179 memset(&transfer, 0, sizeof(transfer)); 180 spi_message_init(&msg); 181 182 transfer.rx_buf = dst; 183 transfer.len = len; 184 185 spi_message_add_tail(&transfer, &msg); 186 ret = spi_sync(qca->spi_dev, &msg); 187 188 if (ret || (msg.actual_length != len)) { 189 qcaspi_spi_error(qca); 190 return 0; 191 } 192 193 return len; 194 } 195 196 static int 197 qcaspi_tx_cmd(struct qcaspi *qca, u16 cmd) 198 { 199 __be16 tx_data; 200 struct spi_message msg; 201 struct spi_transfer transfer; 202 int ret; 203 204 memset(&transfer, 0, sizeof(transfer)); 205 206 spi_message_init(&msg); 207 208 tx_data = cpu_to_be16(cmd); 209 transfer.len = sizeof(cmd); 210 transfer.tx_buf = &tx_data; 211 spi_message_add_tail(&transfer, &msg); 212 213 ret = spi_sync(qca->spi_dev, &msg); 214 215 if (!ret) 216 ret = msg.status; 217 218 if (ret) 219 qcaspi_spi_error(qca); 220 221 return ret; 222 } 223 224 static int 225 qcaspi_tx_frame(struct qcaspi *qca, struct sk_buff *skb) 226 { 227 u32 count; 228 u32 written; 229 u32 offset; 230 u32 len; 231 232 len = skb->len; 233 234 qcaspi_write_register(qca, SPI_REG_BFR_SIZE, len, wr_verify); 235 if (qca->legacy_mode) 236 qcaspi_tx_cmd(qca, QCA7K_SPI_WRITE | QCA7K_SPI_EXTERNAL); 237 238 offset = 0; 239 while (len) { 240 count = len; 241 if (count > qca->burst_len) 242 count = qca->burst_len; 243 244 if (qca->legacy_mode) { 245 written = qcaspi_write_legacy(qca, 246 skb->data + offset, 247 count); 248 } else { 249 written = qcaspi_write_burst(qca, 250 skb->data + offset, 251 count); 252 } 253 254 if (written != count) 255 return -1; 256 257 offset += count; 258 len -= count; 259 } 260 261 return 0; 262 } 263 264 static int 265 qcaspi_transmit(struct qcaspi *qca) 266 { 267 struct net_device_stats *n_stats = &qca->net_dev->stats; 268 u16 available = 0; 269 u32 pkt_len; 270 u16 new_head; 271 u16 packets = 0; 272 273 if (qca->txr.skb[qca->txr.head] == NULL) 274 return 0; 275 276 qcaspi_read_register(qca, SPI_REG_WRBUF_SPC_AVA, &available); 277 278 if (available > QCASPI_HW_BUF_LEN) { 279 /* This could only happen by interferences on the SPI line. 280 * So retry later ... 281 */ 282 qca->stats.buf_avail_err++; 283 return -1; 284 } 285 286 while (qca->txr.skb[qca->txr.head]) { 287 pkt_len = qca->txr.skb[qca->txr.head]->len + QCASPI_HW_PKT_LEN; 288 289 if (available < pkt_len) { 290 if (packets == 0) 291 qca->stats.write_buf_miss++; 292 break; 293 } 294 295 if (qcaspi_tx_frame(qca, qca->txr.skb[qca->txr.head]) == -1) { 296 qca->stats.write_err++; 297 return -1; 298 } 299 300 packets++; 301 n_stats->tx_packets++; 302 n_stats->tx_bytes += qca->txr.skb[qca->txr.head]->len; 303 available -= pkt_len; 304 305 /* remove the skb from the queue */ 306 /* XXX After inconsistent lock states netif_tx_lock() 307 * has been replaced by netif_tx_lock_bh() and so on. 308 */ 309 netif_tx_lock_bh(qca->net_dev); 310 dev_kfree_skb(qca->txr.skb[qca->txr.head]); 311 qca->txr.skb[qca->txr.head] = NULL; 312 qca->txr.size -= pkt_len; 313 new_head = qca->txr.head + 1; 314 if (new_head >= qca->txr.count) 315 new_head = 0; 316 qca->txr.head = new_head; 317 if (netif_queue_stopped(qca->net_dev)) 318 netif_wake_queue(qca->net_dev); 319 netif_tx_unlock_bh(qca->net_dev); 320 } 321 322 return 0; 323 } 324 325 static int 326 qcaspi_receive(struct qcaspi *qca) 327 { 328 struct net_device *net_dev = qca->net_dev; 329 struct net_device_stats *n_stats = &net_dev->stats; 330 u16 available = 0; 331 u32 bytes_read; 332 u8 *cp; 333 334 /* Allocate rx SKB if we don't have one available. */ 335 if (!qca->rx_skb) { 336 qca->rx_skb = netdev_alloc_skb_ip_align(net_dev, 337 net_dev->mtu + 338 VLAN_ETH_HLEN); 339 if (!qca->rx_skb) { 340 netdev_dbg(net_dev, "out of RX resources\n"); 341 qca->stats.out_of_mem++; 342 return -1; 343 } 344 } 345 346 /* Read the packet size. */ 347 qcaspi_read_register(qca, SPI_REG_RDBUF_BYTE_AVA, &available); 348 349 netdev_dbg(net_dev, "qcaspi_receive: SPI_REG_RDBUF_BYTE_AVA: Value: %04x\n", 350 available); 351 352 if (available > QCASPI_HW_BUF_LEN + QCASPI_HW_PKT_LEN) { 353 /* This could only happen by interferences on the SPI line. 354 * So retry later ... 355 */ 356 qca->stats.buf_avail_err++; 357 return -1; 358 } else if (available == 0) { 359 netdev_dbg(net_dev, "qcaspi_receive called without any data being available!\n"); 360 return -1; 361 } 362 363 qcaspi_write_register(qca, SPI_REG_BFR_SIZE, available, wr_verify); 364 365 if (qca->legacy_mode) 366 qcaspi_tx_cmd(qca, QCA7K_SPI_READ | QCA7K_SPI_EXTERNAL); 367 368 while (available) { 369 u32 count = available; 370 371 if (count > qca->burst_len) 372 count = qca->burst_len; 373 374 if (qca->legacy_mode) { 375 bytes_read = qcaspi_read_legacy(qca, qca->rx_buffer, 376 count); 377 } else { 378 bytes_read = qcaspi_read_burst(qca, qca->rx_buffer, 379 count); 380 } 381 382 netdev_dbg(net_dev, "available: %d, byte read: %d\n", 383 available, bytes_read); 384 385 if (bytes_read) { 386 available -= bytes_read; 387 } else { 388 qca->stats.read_err++; 389 return -1; 390 } 391 392 cp = qca->rx_buffer; 393 394 while ((bytes_read--) && (qca->rx_skb)) { 395 s32 retcode; 396 397 retcode = qcafrm_fsm_decode(&qca->frm_handle, 398 qca->rx_skb->data, 399 skb_tailroom(qca->rx_skb), 400 *cp); 401 cp++; 402 switch (retcode) { 403 case QCAFRM_GATHER: 404 case QCAFRM_NOHEAD: 405 break; 406 case QCAFRM_NOTAIL: 407 netdev_dbg(net_dev, "no RX tail\n"); 408 n_stats->rx_errors++; 409 n_stats->rx_dropped++; 410 break; 411 case QCAFRM_INVLEN: 412 netdev_dbg(net_dev, "invalid RX length\n"); 413 n_stats->rx_errors++; 414 n_stats->rx_dropped++; 415 break; 416 default: 417 qca->rx_skb->dev = qca->net_dev; 418 n_stats->rx_packets++; 419 n_stats->rx_bytes += retcode; 420 skb_put(qca->rx_skb, retcode); 421 qca->rx_skb->protocol = eth_type_trans( 422 qca->rx_skb, qca->rx_skb->dev); 423 skb_checksum_none_assert(qca->rx_skb); 424 netif_rx(qca->rx_skb); 425 qca->rx_skb = netdev_alloc_skb_ip_align(net_dev, 426 net_dev->mtu + VLAN_ETH_HLEN); 427 if (!qca->rx_skb) { 428 netdev_dbg(net_dev, "out of RX resources\n"); 429 n_stats->rx_errors++; 430 qca->stats.out_of_mem++; 431 break; 432 } 433 } 434 } 435 } 436 437 return 0; 438 } 439 440 /* Check that tx ring stores only so much bytes 441 * that fit into the internal QCA buffer. 442 */ 443 444 static int 445 qcaspi_tx_ring_has_space(struct tx_ring *txr) 446 { 447 if (txr->skb[txr->tail]) 448 return 0; 449 450 return (txr->size + QCAFRM_MAX_LEN < QCASPI_HW_BUF_LEN) ? 1 : 0; 451 } 452 453 /* Flush the tx ring. This function is only safe to 454 * call from the qcaspi_spi_thread. 455 */ 456 457 static void 458 qcaspi_flush_tx_ring(struct qcaspi *qca) 459 { 460 int i; 461 462 /* XXX After inconsistent lock states netif_tx_lock() 463 * has been replaced by netif_tx_lock_bh() and so on. 464 */ 465 netif_tx_lock_bh(qca->net_dev); 466 for (i = 0; i < QCASPI_TX_RING_MAX_LEN; i++) { 467 if (qca->txr.skb[i]) { 468 dev_kfree_skb(qca->txr.skb[i]); 469 qca->txr.skb[i] = NULL; 470 qca->net_dev->stats.tx_dropped++; 471 } 472 } 473 qca->txr.tail = 0; 474 qca->txr.head = 0; 475 qca->txr.size = 0; 476 netif_tx_unlock_bh(qca->net_dev); 477 } 478 479 static void 480 qcaspi_qca7k_sync(struct qcaspi *qca, int event) 481 { 482 u16 signature = 0; 483 u16 spi_config; 484 u16 wrbuf_space = 0; 485 486 if (event == QCASPI_EVENT_CPUON) { 487 /* Read signature twice, if not valid 488 * go back to unknown state. 489 */ 490 qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature); 491 qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature); 492 if (signature != QCASPI_GOOD_SIGNATURE) { 493 if (qca->sync == QCASPI_SYNC_READY) 494 qca->stats.bad_signature++; 495 496 qca->sync = QCASPI_SYNC_UNKNOWN; 497 netdev_dbg(qca->net_dev, "sync: got CPU on, but signature was invalid, restart\n"); 498 return; 499 } else { 500 /* ensure that the WRBUF is empty */ 501 qcaspi_read_register(qca, SPI_REG_WRBUF_SPC_AVA, 502 &wrbuf_space); 503 if (wrbuf_space != QCASPI_HW_BUF_LEN) { 504 netdev_dbg(qca->net_dev, "sync: got CPU on, but wrbuf not empty. reset!\n"); 505 qca->sync = QCASPI_SYNC_UNKNOWN; 506 } else { 507 netdev_dbg(qca->net_dev, "sync: got CPU on, now in sync\n"); 508 qca->sync = QCASPI_SYNC_READY; 509 return; 510 } 511 } 512 } 513 514 switch (qca->sync) { 515 case QCASPI_SYNC_READY: 516 /* Check signature twice, if not valid go to unknown state. */ 517 qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature); 518 if (signature != QCASPI_GOOD_SIGNATURE) 519 qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature); 520 521 if (signature != QCASPI_GOOD_SIGNATURE) { 522 qca->sync = QCASPI_SYNC_UNKNOWN; 523 qca->stats.bad_signature++; 524 netdev_dbg(qca->net_dev, "sync: bad signature, restart\n"); 525 /* don't reset right away */ 526 return; 527 } 528 break; 529 case QCASPI_SYNC_UNKNOWN: 530 /* Read signature, if not valid stay in unknown state */ 531 qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature); 532 if (signature != QCASPI_GOOD_SIGNATURE) { 533 netdev_dbg(qca->net_dev, "sync: could not read signature to reset device, retry.\n"); 534 return; 535 } 536 537 /* TODO: use GPIO to reset QCA7000 in legacy mode*/ 538 netdev_dbg(qca->net_dev, "sync: resetting device.\n"); 539 qcaspi_read_register(qca, SPI_REG_SPI_CONFIG, &spi_config); 540 spi_config |= QCASPI_SLAVE_RESET_BIT; 541 qcaspi_write_register(qca, SPI_REG_SPI_CONFIG, spi_config, 0); 542 543 qca->sync = QCASPI_SYNC_RESET; 544 qca->stats.trig_reset++; 545 qca->reset_count = 0; 546 break; 547 case QCASPI_SYNC_RESET: 548 qca->reset_count++; 549 netdev_dbg(qca->net_dev, "sync: waiting for CPU on, count %u.\n", 550 qca->reset_count); 551 if (qca->reset_count >= QCASPI_RESET_TIMEOUT) { 552 /* reset did not seem to take place, try again */ 553 qca->sync = QCASPI_SYNC_UNKNOWN; 554 qca->stats.reset_timeout++; 555 netdev_dbg(qca->net_dev, "sync: reset timeout, restarting process.\n"); 556 } 557 break; 558 } 559 } 560 561 static int 562 qcaspi_spi_thread(void *data) 563 { 564 struct qcaspi *qca = data; 565 u16 intr_cause = 0; 566 567 netdev_info(qca->net_dev, "SPI thread created\n"); 568 while (!kthread_should_stop()) { 569 set_current_state(TASK_INTERRUPTIBLE); 570 if (kthread_should_park()) { 571 netif_tx_disable(qca->net_dev); 572 netif_carrier_off(qca->net_dev); 573 qcaspi_flush_tx_ring(qca); 574 kthread_parkme(); 575 if (qca->sync == QCASPI_SYNC_READY) { 576 netif_carrier_on(qca->net_dev); 577 netif_wake_queue(qca->net_dev); 578 } 579 continue; 580 } 581 582 if ((qca->intr_req == qca->intr_svc) && 583 !qca->txr.skb[qca->txr.head]) 584 schedule(); 585 586 set_current_state(TASK_RUNNING); 587 588 netdev_dbg(qca->net_dev, "have work to do. int: %d, tx_skb: %p\n", 589 qca->intr_req - qca->intr_svc, 590 qca->txr.skb[qca->txr.head]); 591 592 qcaspi_qca7k_sync(qca, QCASPI_EVENT_UPDATE); 593 594 if (qca->sync != QCASPI_SYNC_READY) { 595 netdev_dbg(qca->net_dev, "sync: not ready %u, turn off carrier and flush\n", 596 (unsigned int)qca->sync); 597 netif_stop_queue(qca->net_dev); 598 netif_carrier_off(qca->net_dev); 599 qcaspi_flush_tx_ring(qca); 600 msleep(QCASPI_QCA7K_REBOOT_TIME_MS); 601 } 602 603 if (qca->intr_svc != qca->intr_req) { 604 qca->intr_svc = qca->intr_req; 605 start_spi_intr_handling(qca, &intr_cause); 606 607 if (intr_cause & SPI_INT_CPU_ON) { 608 qcaspi_qca7k_sync(qca, QCASPI_EVENT_CPUON); 609 610 /* Frame decoding in progress */ 611 if (qca->frm_handle.state != qca->frm_handle.init) 612 qca->net_dev->stats.rx_dropped++; 613 614 qcafrm_fsm_init_spi(&qca->frm_handle); 615 qca->stats.device_reset++; 616 617 /* not synced. */ 618 if (qca->sync != QCASPI_SYNC_READY) 619 continue; 620 621 netif_wake_queue(qca->net_dev); 622 netif_carrier_on(qca->net_dev); 623 } 624 625 if (intr_cause & SPI_INT_RDBUF_ERR) { 626 /* restart sync */ 627 netdev_dbg(qca->net_dev, "===> rdbuf error!\n"); 628 qca->stats.read_buf_err++; 629 qca->sync = QCASPI_SYNC_UNKNOWN; 630 continue; 631 } 632 633 if (intr_cause & SPI_INT_WRBUF_ERR) { 634 /* restart sync */ 635 netdev_dbg(qca->net_dev, "===> wrbuf error!\n"); 636 qca->stats.write_buf_err++; 637 qca->sync = QCASPI_SYNC_UNKNOWN; 638 continue; 639 } 640 641 /* can only handle other interrupts 642 * if sync has occurred 643 */ 644 if (qca->sync == QCASPI_SYNC_READY) { 645 if (intr_cause & SPI_INT_PKT_AVLBL) 646 qcaspi_receive(qca); 647 } 648 649 end_spi_intr_handling(qca, intr_cause); 650 } 651 652 if (qca->sync == QCASPI_SYNC_READY) 653 qcaspi_transmit(qca); 654 } 655 set_current_state(TASK_RUNNING); 656 netdev_info(qca->net_dev, "SPI thread exit\n"); 657 658 return 0; 659 } 660 661 static irqreturn_t 662 qcaspi_intr_handler(int irq, void *data) 663 { 664 struct qcaspi *qca = data; 665 666 qca->intr_req++; 667 if (qca->spi_thread) 668 wake_up_process(qca->spi_thread); 669 670 return IRQ_HANDLED; 671 } 672 673 static int 674 qcaspi_netdev_open(struct net_device *dev) 675 { 676 struct qcaspi *qca = netdev_priv(dev); 677 struct task_struct *thread; 678 679 if (!qca) 680 return -EINVAL; 681 682 qca->intr_req = 1; 683 qca->intr_svc = 0; 684 qca->sync = QCASPI_SYNC_UNKNOWN; 685 qcafrm_fsm_init_spi(&qca->frm_handle); 686 687 thread = kthread_run((void *)qcaspi_spi_thread, 688 qca, "%s", dev->name); 689 690 if (IS_ERR(thread)) { 691 netdev_err(dev, "%s: unable to start kernel thread.\n", 692 QCASPI_DRV_NAME); 693 return PTR_ERR(thread); 694 } 695 696 qca->spi_thread = thread; 697 698 enable_irq(qca->spi_dev->irq); 699 700 /* SPI thread takes care of TX queue */ 701 702 return 0; 703 } 704 705 static int 706 qcaspi_netdev_close(struct net_device *dev) 707 { 708 struct qcaspi *qca = netdev_priv(dev); 709 710 netif_stop_queue(dev); 711 712 qcaspi_write_register(qca, SPI_REG_INTR_ENABLE, 0, wr_verify); 713 disable_irq(qca->spi_dev->irq); 714 715 if (qca->spi_thread) { 716 kthread_stop(qca->spi_thread); 717 qca->spi_thread = NULL; 718 } 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 = (QCAFRM_MAX_MTU + VLAN_ETH_HLEN + QCAFRM_HEADER_LEN + 819 QCAFRM_FOOTER_LEN + QCASPI_HW_PKT_LEN) * QCASPI_RX_MAX_FRAMES; 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->needed_tailroom = ALIGN(QCAFRM_FOOTER_LEN + QCAFRM_MIN_LEN, 4); 869 dev->needed_headroom = ALIGN(QCAFRM_HEADER_LEN, 4); 870 dev->tx_queue_len = 100; 871 872 /* MTU range: 46 - 1500 */ 873 dev->min_mtu = QCAFRM_MIN_MTU; 874 dev->max_mtu = QCAFRM_MAX_MTU; 875 876 qca = netdev_priv(dev); 877 memset(qca, 0, sizeof(struct qcaspi)); 878 879 memset(&qca->txr, 0, sizeof(qca->txr)); 880 qca->txr.count = QCASPI_TX_RING_MAX_LEN; 881 } 882 883 static const struct of_device_id qca_spi_of_match[] = { 884 { .compatible = "qca,qca7000" }, 885 { /* sentinel */ } 886 }; 887 MODULE_DEVICE_TABLE(of, qca_spi_of_match); 888 889 static int 890 qca_spi_probe(struct spi_device *spi) 891 { 892 struct qcaspi *qca = NULL; 893 struct net_device *qcaspi_devs = NULL; 894 u8 legacy_mode = 0; 895 u16 signature; 896 int ret; 897 898 if (!spi->dev.of_node) { 899 dev_err(&spi->dev, "Missing device tree\n"); 900 return -EINVAL; 901 } 902 903 legacy_mode = of_property_read_bool(spi->dev.of_node, 904 "qca,legacy-mode"); 905 906 if (qcaspi_clkspeed == 0) { 907 if (spi->max_speed_hz) 908 qcaspi_clkspeed = spi->max_speed_hz; 909 else 910 qcaspi_clkspeed = QCASPI_CLK_SPEED; 911 } 912 913 if ((qcaspi_clkspeed < QCASPI_CLK_SPEED_MIN) || 914 (qcaspi_clkspeed > QCASPI_CLK_SPEED_MAX)) { 915 dev_err(&spi->dev, "Invalid clkspeed: %d\n", 916 qcaspi_clkspeed); 917 return -EINVAL; 918 } 919 920 if ((qcaspi_burst_len < QCASPI_BURST_LEN_MIN) || 921 (qcaspi_burst_len > QCASPI_BURST_LEN_MAX)) { 922 dev_err(&spi->dev, "Invalid burst len: %d\n", 923 qcaspi_burst_len); 924 return -EINVAL; 925 } 926 927 if ((qcaspi_pluggable < QCASPI_PLUGGABLE_MIN) || 928 (qcaspi_pluggable > QCASPI_PLUGGABLE_MAX)) { 929 dev_err(&spi->dev, "Invalid pluggable: %d\n", 930 qcaspi_pluggable); 931 return -EINVAL; 932 } 933 934 if (wr_verify < QCASPI_WRITE_VERIFY_MIN || 935 wr_verify > QCASPI_WRITE_VERIFY_MAX) { 936 dev_err(&spi->dev, "Invalid write verify: %d\n", 937 wr_verify); 938 return -EINVAL; 939 } 940 941 dev_info(&spi->dev, "ver=%s, clkspeed=%d, burst_len=%d, pluggable=%d\n", 942 QCASPI_DRV_VERSION, 943 qcaspi_clkspeed, 944 qcaspi_burst_len, 945 qcaspi_pluggable); 946 947 spi->mode = SPI_MODE_3; 948 spi->max_speed_hz = qcaspi_clkspeed; 949 if (spi_setup(spi) < 0) { 950 dev_err(&spi->dev, "Unable to setup SPI device\n"); 951 return -EFAULT; 952 } 953 954 qcaspi_devs = alloc_etherdev(sizeof(struct qcaspi)); 955 if (!qcaspi_devs) 956 return -ENOMEM; 957 958 qcaspi_netdev_setup(qcaspi_devs); 959 SET_NETDEV_DEV(qcaspi_devs, &spi->dev); 960 961 qca = netdev_priv(qcaspi_devs); 962 if (!qca) { 963 free_netdev(qcaspi_devs); 964 dev_err(&spi->dev, "Fail to retrieve private structure\n"); 965 return -ENOMEM; 966 } 967 qca->net_dev = qcaspi_devs; 968 qca->spi_dev = spi; 969 qca->legacy_mode = legacy_mode; 970 971 spi_set_drvdata(spi, qcaspi_devs); 972 973 ret = devm_request_irq(&spi->dev, spi->irq, qcaspi_intr_handler, 974 IRQF_NO_AUTOEN, qca->net_dev->name, qca); 975 if (ret) { 976 dev_err(&spi->dev, "Unable to get IRQ %d (irqval=%d).\n", 977 spi->irq, ret); 978 free_netdev(qcaspi_devs); 979 return ret; 980 } 981 982 ret = of_get_ethdev_address(spi->dev.of_node, qca->net_dev); 983 if (ret) { 984 eth_hw_addr_random(qca->net_dev); 985 dev_info(&spi->dev, "Using random MAC address: %pM\n", 986 qca->net_dev->dev_addr); 987 } 988 989 netif_carrier_off(qca->net_dev); 990 991 if (!qcaspi_pluggable) { 992 qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature); 993 qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature); 994 995 if (signature != QCASPI_GOOD_SIGNATURE) { 996 dev_err(&spi->dev, "Invalid signature (expected 0x%04x, read 0x%04x)\n", 997 QCASPI_GOOD_SIGNATURE, signature); 998 free_netdev(qcaspi_devs); 999 return -EFAULT; 1000 } 1001 } 1002 1003 if (register_netdev(qcaspi_devs)) { 1004 dev_err(&spi->dev, "Unable to register net device %s\n", 1005 qcaspi_devs->name); 1006 free_netdev(qcaspi_devs); 1007 return -EFAULT; 1008 } 1009 1010 qcaspi_init_device_debugfs(qca); 1011 1012 return 0; 1013 } 1014 1015 static void 1016 qca_spi_remove(struct spi_device *spi) 1017 { 1018 struct net_device *qcaspi_devs = spi_get_drvdata(spi); 1019 struct qcaspi *qca = netdev_priv(qcaspi_devs); 1020 1021 qcaspi_remove_device_debugfs(qca); 1022 1023 unregister_netdev(qcaspi_devs); 1024 free_netdev(qcaspi_devs); 1025 } 1026 1027 static const struct spi_device_id qca_spi_id[] = { 1028 { "qca7000", 0 }, 1029 { /* sentinel */ } 1030 }; 1031 MODULE_DEVICE_TABLE(spi, qca_spi_id); 1032 1033 static struct spi_driver qca_spi_driver = { 1034 .driver = { 1035 .name = QCASPI_DRV_NAME, 1036 .of_match_table = qca_spi_of_match, 1037 }, 1038 .id_table = qca_spi_id, 1039 .probe = qca_spi_probe, 1040 .remove = qca_spi_remove, 1041 }; 1042 module_spi_driver(qca_spi_driver); 1043 1044 MODULE_DESCRIPTION("Qualcomm Atheros QCA7000 SPI Driver"); 1045 MODULE_AUTHOR("Qualcomm Atheros Communications"); 1046 MODULE_AUTHOR("Stefan Wahren <wahrenst@gmx.net>"); 1047 MODULE_LICENSE("Dual BSD/GPL"); 1048 MODULE_VERSION(QCASPI_DRV_VERSION); 1049