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 #define SPI_INTR 0 39 #define SPI_RESET 1 40 41 /* Modules parameters */ 42 #define QCASPI_CLK_SPEED_MIN 1000000 43 #define QCASPI_CLK_SPEED_MAX 16000000 44 #define QCASPI_CLK_SPEED 8000000 45 static int qcaspi_clkspeed; 46 module_param(qcaspi_clkspeed, int, 0); 47 MODULE_PARM_DESC(qcaspi_clkspeed, "SPI bus clock speed (Hz). Use 1000000-16000000."); 48 49 #define QCASPI_BURST_LEN_MIN 1 50 #define QCASPI_BURST_LEN_MAX MAX_DMA_BURST_LEN 51 static int qcaspi_burst_len = MAX_DMA_BURST_LEN; 52 module_param(qcaspi_burst_len, int, 0); 53 MODULE_PARM_DESC(qcaspi_burst_len, "Number of data bytes per burst. Use 1-5000."); 54 55 #define QCASPI_PLUGGABLE_MIN 0 56 #define QCASPI_PLUGGABLE_MAX 1 57 static int qcaspi_pluggable = QCASPI_PLUGGABLE_MIN; 58 module_param(qcaspi_pluggable, int, 0); 59 MODULE_PARM_DESC(qcaspi_pluggable, "Pluggable SPI connection (yes/no)."); 60 61 #define QCASPI_WRITE_VERIFY_MIN 0 62 #define QCASPI_WRITE_VERIFY_MAX 3 63 static int wr_verify = QCASPI_WRITE_VERIFY_MIN; 64 module_param(wr_verify, int, 0); 65 MODULE_PARM_DESC(wr_verify, "SPI register write verify trails. Use 0-3."); 66 67 #define QCASPI_TX_TIMEOUT (1 * HZ) 68 #define QCASPI_QCA7K_REBOOT_TIME_MS 1000 69 70 static void 71 start_spi_intr_handling(struct qcaspi *qca, u16 *intr_cause) 72 { 73 *intr_cause = 0; 74 75 qcaspi_write_register(qca, SPI_REG_INTR_ENABLE, 0, wr_verify); 76 qcaspi_read_register(qca, SPI_REG_INTR_CAUSE, intr_cause); 77 netdev_dbg(qca->net_dev, "interrupts: 0x%04x\n", *intr_cause); 78 } 79 80 static void 81 end_spi_intr_handling(struct qcaspi *qca, u16 intr_cause) 82 { 83 u16 intr_enable = (SPI_INT_CPU_ON | 84 SPI_INT_PKT_AVLBL | 85 SPI_INT_RDBUF_ERR | 86 SPI_INT_WRBUF_ERR); 87 88 qcaspi_write_register(qca, SPI_REG_INTR_CAUSE, intr_cause, 0); 89 qcaspi_write_register(qca, SPI_REG_INTR_ENABLE, intr_enable, wr_verify); 90 netdev_dbg(qca->net_dev, "acking int: 0x%04x\n", intr_cause); 91 } 92 93 static u32 94 qcaspi_write_burst(struct qcaspi *qca, u8 *src, u32 len) 95 { 96 __be16 cmd; 97 struct spi_message msg; 98 struct spi_transfer transfer[2]; 99 int ret; 100 101 memset(&transfer, 0, sizeof(transfer)); 102 spi_message_init(&msg); 103 104 cmd = cpu_to_be16(QCA7K_SPI_WRITE | QCA7K_SPI_EXTERNAL); 105 transfer[0].tx_buf = &cmd; 106 transfer[0].len = QCASPI_CMD_LEN; 107 transfer[1].tx_buf = src; 108 transfer[1].len = len; 109 110 spi_message_add_tail(&transfer[0], &msg); 111 spi_message_add_tail(&transfer[1], &msg); 112 ret = spi_sync(qca->spi_dev, &msg); 113 114 if (ret || (msg.actual_length != QCASPI_CMD_LEN + len)) { 115 qcaspi_spi_error(qca); 116 return 0; 117 } 118 119 return len; 120 } 121 122 static u32 123 qcaspi_write_legacy(struct qcaspi *qca, u8 *src, u32 len) 124 { 125 struct spi_message msg; 126 struct spi_transfer transfer; 127 int ret; 128 129 memset(&transfer, 0, sizeof(transfer)); 130 spi_message_init(&msg); 131 132 transfer.tx_buf = src; 133 transfer.len = len; 134 135 spi_message_add_tail(&transfer, &msg); 136 ret = spi_sync(qca->spi_dev, &msg); 137 138 if (ret || (msg.actual_length != len)) { 139 qcaspi_spi_error(qca); 140 return 0; 141 } 142 143 return len; 144 } 145 146 static u32 147 qcaspi_read_burst(struct qcaspi *qca, u8 *dst, u32 len) 148 { 149 struct spi_message msg; 150 __be16 cmd; 151 struct spi_transfer transfer[2]; 152 int ret; 153 154 memset(&transfer, 0, sizeof(transfer)); 155 spi_message_init(&msg); 156 157 cmd = cpu_to_be16(QCA7K_SPI_READ | QCA7K_SPI_EXTERNAL); 158 transfer[0].tx_buf = &cmd; 159 transfer[0].len = QCASPI_CMD_LEN; 160 transfer[1].rx_buf = dst; 161 transfer[1].len = len; 162 163 spi_message_add_tail(&transfer[0], &msg); 164 spi_message_add_tail(&transfer[1], &msg); 165 ret = spi_sync(qca->spi_dev, &msg); 166 167 if (ret || (msg.actual_length != QCASPI_CMD_LEN + len)) { 168 qcaspi_spi_error(qca); 169 return 0; 170 } 171 172 return len; 173 } 174 175 static u32 176 qcaspi_read_legacy(struct qcaspi *qca, u8 *dst, u32 len) 177 { 178 struct spi_message msg; 179 struct spi_transfer transfer; 180 int ret; 181 182 memset(&transfer, 0, sizeof(transfer)); 183 spi_message_init(&msg); 184 185 transfer.rx_buf = dst; 186 transfer.len = len; 187 188 spi_message_add_tail(&transfer, &msg); 189 ret = spi_sync(qca->spi_dev, &msg); 190 191 if (ret || (msg.actual_length != len)) { 192 qcaspi_spi_error(qca); 193 return 0; 194 } 195 196 return len; 197 } 198 199 static int 200 qcaspi_tx_cmd(struct qcaspi *qca, u16 cmd) 201 { 202 __be16 tx_data; 203 struct spi_message msg; 204 struct spi_transfer transfer; 205 int ret; 206 207 memset(&transfer, 0, sizeof(transfer)); 208 209 spi_message_init(&msg); 210 211 tx_data = cpu_to_be16(cmd); 212 transfer.len = sizeof(cmd); 213 transfer.tx_buf = &tx_data; 214 spi_message_add_tail(&transfer, &msg); 215 216 ret = spi_sync(qca->spi_dev, &msg); 217 218 if (!ret) 219 ret = msg.status; 220 221 if (ret) 222 qcaspi_spi_error(qca); 223 224 return ret; 225 } 226 227 static int 228 qcaspi_tx_frame(struct qcaspi *qca, struct sk_buff *skb) 229 { 230 u32 count; 231 u32 written; 232 u32 offset; 233 u32 len; 234 235 len = skb->len; 236 237 qcaspi_write_register(qca, SPI_REG_BFR_SIZE, len, wr_verify); 238 if (qca->legacy_mode) 239 qcaspi_tx_cmd(qca, QCA7K_SPI_WRITE | QCA7K_SPI_EXTERNAL); 240 241 offset = 0; 242 while (len) { 243 count = len; 244 if (count > qca->burst_len) 245 count = qca->burst_len; 246 247 if (qca->legacy_mode) { 248 written = qcaspi_write_legacy(qca, 249 skb->data + offset, 250 count); 251 } else { 252 written = qcaspi_write_burst(qca, 253 skb->data + offset, 254 count); 255 } 256 257 if (written != count) 258 return -1; 259 260 offset += count; 261 len -= count; 262 } 263 264 return 0; 265 } 266 267 static int 268 qcaspi_transmit(struct qcaspi *qca) 269 { 270 struct net_device_stats *n_stats = &qca->net_dev->stats; 271 u16 available = 0; 272 u32 pkt_len; 273 u16 new_head; 274 u16 packets = 0; 275 276 if (qca->txr.skb[qca->txr.head] == NULL) 277 return 0; 278 279 qcaspi_read_register(qca, SPI_REG_WRBUF_SPC_AVA, &available); 280 281 if (available > QCASPI_HW_BUF_LEN) { 282 /* This could only happen by interferences on the SPI line. 283 * So retry later ... 284 */ 285 qca->stats.buf_avail_err++; 286 return -1; 287 } 288 289 while (qca->txr.skb[qca->txr.head]) { 290 pkt_len = qca->txr.skb[qca->txr.head]->len + QCASPI_HW_PKT_LEN; 291 292 if (available < pkt_len) { 293 if (packets == 0) 294 qca->stats.write_buf_miss++; 295 break; 296 } 297 298 if (qcaspi_tx_frame(qca, qca->txr.skb[qca->txr.head]) == -1) { 299 qca->stats.write_err++; 300 return -1; 301 } 302 303 packets++; 304 n_stats->tx_packets++; 305 n_stats->tx_bytes += qca->txr.skb[qca->txr.head]->len; 306 available -= pkt_len; 307 308 /* remove the skb from the queue */ 309 /* XXX After inconsistent lock states netif_tx_lock() 310 * has been replaced by netif_tx_lock_bh() and so on. 311 */ 312 netif_tx_lock_bh(qca->net_dev); 313 dev_kfree_skb(qca->txr.skb[qca->txr.head]); 314 qca->txr.skb[qca->txr.head] = NULL; 315 qca->txr.size -= pkt_len; 316 new_head = qca->txr.head + 1; 317 if (new_head >= qca->txr.count) 318 new_head = 0; 319 qca->txr.head = new_head; 320 if (netif_queue_stopped(qca->net_dev)) 321 netif_wake_queue(qca->net_dev); 322 netif_tx_unlock_bh(qca->net_dev); 323 } 324 325 return 0; 326 } 327 328 static int 329 qcaspi_receive(struct qcaspi *qca) 330 { 331 struct net_device *net_dev = qca->net_dev; 332 struct net_device_stats *n_stats = &net_dev->stats; 333 u16 available = 0; 334 u32 bytes_read; 335 u8 *cp; 336 337 /* Allocate rx SKB if we don't have one available. */ 338 if (!qca->rx_skb) { 339 qca->rx_skb = netdev_alloc_skb_ip_align(net_dev, 340 net_dev->mtu + 341 VLAN_ETH_HLEN); 342 if (!qca->rx_skb) { 343 netdev_dbg(net_dev, "out of RX resources\n"); 344 qca->stats.out_of_mem++; 345 return -1; 346 } 347 } 348 349 /* Read the packet size. */ 350 qcaspi_read_register(qca, SPI_REG_RDBUF_BYTE_AVA, &available); 351 352 netdev_dbg(net_dev, "qcaspi_receive: SPI_REG_RDBUF_BYTE_AVA: Value: %04x\n", 353 available); 354 355 if (available > QCASPI_HW_BUF_LEN + QCASPI_HW_PKT_LEN) { 356 /* This could only happen by interferences on the SPI line. 357 * So retry later ... 358 */ 359 qca->stats.buf_avail_err++; 360 return -1; 361 } else if (available == 0) { 362 netdev_dbg(net_dev, "qcaspi_receive called without any data being available!\n"); 363 return -1; 364 } 365 366 qcaspi_write_register(qca, SPI_REG_BFR_SIZE, available, wr_verify); 367 368 if (qca->legacy_mode) 369 qcaspi_tx_cmd(qca, QCA7K_SPI_READ | QCA7K_SPI_EXTERNAL); 370 371 while (available) { 372 u32 count = available; 373 374 if (count > qca->burst_len) 375 count = qca->burst_len; 376 377 if (qca->legacy_mode) { 378 bytes_read = qcaspi_read_legacy(qca, qca->rx_buffer, 379 count); 380 } else { 381 bytes_read = qcaspi_read_burst(qca, qca->rx_buffer, 382 count); 383 } 384 385 netdev_dbg(net_dev, "available: %d, byte read: %d\n", 386 available, bytes_read); 387 388 if (bytes_read) { 389 available -= bytes_read; 390 } else { 391 qca->stats.read_err++; 392 return -1; 393 } 394 395 cp = qca->rx_buffer; 396 397 while ((bytes_read--) && (qca->rx_skb)) { 398 s32 retcode; 399 400 retcode = qcafrm_fsm_decode(&qca->frm_handle, 401 qca->rx_skb->data, 402 skb_tailroom(qca->rx_skb), 403 *cp); 404 cp++; 405 switch (retcode) { 406 case QCAFRM_GATHER: 407 case QCAFRM_NOHEAD: 408 break; 409 case QCAFRM_NOTAIL: 410 netdev_dbg(net_dev, "no RX tail\n"); 411 n_stats->rx_errors++; 412 n_stats->rx_dropped++; 413 break; 414 case QCAFRM_INVLEN: 415 netdev_dbg(net_dev, "invalid RX length\n"); 416 n_stats->rx_errors++; 417 n_stats->rx_dropped++; 418 break; 419 default: 420 qca->rx_skb->dev = qca->net_dev; 421 n_stats->rx_packets++; 422 n_stats->rx_bytes += retcode; 423 skb_put(qca->rx_skb, retcode); 424 qca->rx_skb->protocol = eth_type_trans( 425 qca->rx_skb, qca->rx_skb->dev); 426 skb_checksum_none_assert(qca->rx_skb); 427 netif_rx(qca->rx_skb); 428 qca->rx_skb = netdev_alloc_skb_ip_align(net_dev, 429 net_dev->mtu + VLAN_ETH_HLEN); 430 if (!qca->rx_skb) { 431 netdev_dbg(net_dev, "out of RX resources\n"); 432 n_stats->rx_errors++; 433 qca->stats.out_of_mem++; 434 break; 435 } 436 } 437 } 438 } 439 440 return 0; 441 } 442 443 /* Check that tx ring stores only so much bytes 444 * that fit into the internal QCA buffer. 445 */ 446 447 static int 448 qcaspi_tx_ring_has_space(struct tx_ring *txr) 449 { 450 if (txr->skb[txr->tail]) 451 return 0; 452 453 return (txr->size + QCAFRM_MAX_LEN < QCASPI_HW_BUF_LEN) ? 1 : 0; 454 } 455 456 /* Flush the tx ring. This function is only safe to 457 * call from the qcaspi_spi_thread. 458 */ 459 460 static void 461 qcaspi_flush_tx_ring(struct qcaspi *qca) 462 { 463 int i; 464 465 /* XXX After inconsistent lock states netif_tx_lock() 466 * has been replaced by netif_tx_lock_bh() and so on. 467 */ 468 netif_tx_lock_bh(qca->net_dev); 469 for (i = 0; i < QCASPI_TX_RING_MAX_LEN; i++) { 470 if (qca->txr.skb[i]) { 471 dev_kfree_skb(qca->txr.skb[i]); 472 qca->txr.skb[i] = NULL; 473 qca->net_dev->stats.tx_dropped++; 474 } 475 } 476 qca->txr.tail = 0; 477 qca->txr.head = 0; 478 qca->txr.size = 0; 479 netif_tx_unlock_bh(qca->net_dev); 480 } 481 482 static void 483 qcaspi_qca7k_sync(struct qcaspi *qca, int event) 484 { 485 u16 signature = 0; 486 u16 spi_config; 487 u16 wrbuf_space = 0; 488 489 if (event == QCASPI_EVENT_CPUON) { 490 /* Read signature twice, if not valid 491 * go back to unknown state. 492 */ 493 qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature); 494 qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature); 495 if (signature != QCASPI_GOOD_SIGNATURE) { 496 if (qca->sync == QCASPI_SYNC_READY) 497 qca->stats.bad_signature++; 498 499 set_bit(SPI_RESET, &qca->flags); 500 netdev_dbg(qca->net_dev, "sync: got CPU on, but signature was invalid, restart\n"); 501 return; 502 } else { 503 /* ensure that the WRBUF is empty */ 504 qcaspi_read_register(qca, SPI_REG_WRBUF_SPC_AVA, 505 &wrbuf_space); 506 if (wrbuf_space != QCASPI_HW_BUF_LEN) { 507 netdev_dbg(qca->net_dev, "sync: got CPU on, but wrbuf not empty. reset!\n"); 508 qca->sync = QCASPI_SYNC_UNKNOWN; 509 qca->stats.buf_avail_err++; 510 } else { 511 netdev_dbg(qca->net_dev, "sync: got CPU on, now in sync\n"); 512 qca->sync = QCASPI_SYNC_READY; 513 return; 514 } 515 } 516 } else { 517 /* Handle reset only on QCASPI_EVENT_UPDATE */ 518 if (test_and_clear_bit(SPI_RESET, &qca->flags)) 519 qca->sync = QCASPI_SYNC_UNKNOWN; 520 } 521 522 switch (qca->sync) { 523 case QCASPI_SYNC_READY: 524 /* Check signature twice, if not valid go to unknown state. */ 525 qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature); 526 if (signature != QCASPI_GOOD_SIGNATURE) 527 qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature); 528 529 if (signature != QCASPI_GOOD_SIGNATURE) { 530 set_bit(SPI_RESET, &qca->flags); 531 qca->stats.bad_signature++; 532 netdev_dbg(qca->net_dev, "sync: bad signature, restart\n"); 533 /* don't reset right away */ 534 return; 535 } 536 break; 537 case QCASPI_SYNC_UNKNOWN: 538 /* Read signature, if not valid stay in unknown state */ 539 qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature); 540 if (signature != QCASPI_GOOD_SIGNATURE) { 541 netdev_dbg(qca->net_dev, "sync: could not read signature to reset device, retry.\n"); 542 return; 543 } 544 545 /* TODO: use GPIO to reset QCA7000 in legacy mode*/ 546 netdev_dbg(qca->net_dev, "sync: resetting device.\n"); 547 qcaspi_read_register(qca, SPI_REG_SPI_CONFIG, &spi_config); 548 spi_config |= QCASPI_SLAVE_RESET_BIT; 549 qcaspi_write_register(qca, SPI_REG_SPI_CONFIG, spi_config, 0); 550 551 qca->sync = QCASPI_SYNC_RESET; 552 qca->stats.trig_reset++; 553 qca->reset_count = 0; 554 break; 555 case QCASPI_SYNC_RESET: 556 qca->reset_count++; 557 netdev_dbg(qca->net_dev, "sync: waiting for CPU on, count %u.\n", 558 qca->reset_count); 559 if (qca->reset_count >= QCASPI_RESET_TIMEOUT) { 560 /* reset did not seem to take place, try again */ 561 set_bit(SPI_RESET, &qca->flags); 562 qca->stats.reset_timeout++; 563 netdev_dbg(qca->net_dev, "sync: reset timeout, restarting process.\n"); 564 } 565 break; 566 } 567 } 568 569 static int 570 qcaspi_spi_thread(void *data) 571 { 572 struct qcaspi *qca = data; 573 u16 intr_cause = 0; 574 575 netdev_info(qca->net_dev, "SPI thread created\n"); 576 while (!kthread_should_stop()) { 577 set_current_state(TASK_INTERRUPTIBLE); 578 if (kthread_should_park()) { 579 netif_tx_disable(qca->net_dev); 580 netif_carrier_off(qca->net_dev); 581 qcaspi_flush_tx_ring(qca); 582 kthread_parkme(); 583 if (qca->sync == QCASPI_SYNC_READY) { 584 netif_carrier_on(qca->net_dev); 585 netif_wake_queue(qca->net_dev); 586 } 587 continue; 588 } 589 590 if (!qca->flags && 591 !qca->txr.skb[qca->txr.head]) 592 schedule(); 593 594 set_current_state(TASK_RUNNING); 595 596 netdev_dbg(qca->net_dev, "have work to do. int: %lu, tx_skb: %p\n", 597 qca->flags, 598 qca->txr.skb[qca->txr.head]); 599 600 qcaspi_qca7k_sync(qca, QCASPI_EVENT_UPDATE); 601 602 if (qca->sync != QCASPI_SYNC_READY) { 603 netdev_dbg(qca->net_dev, "sync: not ready %u, turn off carrier and flush\n", 604 (unsigned int)qca->sync); 605 netif_stop_queue(qca->net_dev); 606 netif_carrier_off(qca->net_dev); 607 qcaspi_flush_tx_ring(qca); 608 msleep(QCASPI_QCA7K_REBOOT_TIME_MS); 609 } 610 611 if (test_and_clear_bit(SPI_INTR, &qca->flags)) { 612 start_spi_intr_handling(qca, &intr_cause); 613 614 if (intr_cause & SPI_INT_CPU_ON) { 615 qcaspi_qca7k_sync(qca, QCASPI_EVENT_CPUON); 616 617 /* Frame decoding in progress */ 618 if (qca->frm_handle.state != qca->frm_handle.init) 619 qca->net_dev->stats.rx_dropped++; 620 621 qcafrm_fsm_init_spi(&qca->frm_handle); 622 qca->stats.device_reset++; 623 624 /* not synced. */ 625 if (qca->sync != QCASPI_SYNC_READY) 626 continue; 627 628 netif_wake_queue(qca->net_dev); 629 netif_carrier_on(qca->net_dev); 630 } 631 632 if (intr_cause & SPI_INT_RDBUF_ERR) { 633 /* restart sync */ 634 netdev_dbg(qca->net_dev, "===> rdbuf error!\n"); 635 qca->stats.read_buf_err++; 636 set_bit(SPI_RESET, &qca->flags); 637 continue; 638 } 639 640 if (intr_cause & SPI_INT_WRBUF_ERR) { 641 /* restart sync */ 642 netdev_dbg(qca->net_dev, "===> wrbuf error!\n"); 643 qca->stats.write_buf_err++; 644 set_bit(SPI_RESET, &qca->flags); 645 continue; 646 } 647 648 /* can only handle other interrupts 649 * if sync has occurred 650 */ 651 if (qca->sync == QCASPI_SYNC_READY) { 652 if (intr_cause & SPI_INT_PKT_AVLBL) 653 qcaspi_receive(qca); 654 } 655 656 end_spi_intr_handling(qca, intr_cause); 657 } 658 659 if (qca->sync == QCASPI_SYNC_READY) 660 qcaspi_transmit(qca); 661 } 662 set_current_state(TASK_RUNNING); 663 netdev_info(qca->net_dev, "SPI thread exit\n"); 664 665 return 0; 666 } 667 668 static irqreturn_t 669 qcaspi_intr_handler(int irq, void *data) 670 { 671 struct qcaspi *qca = data; 672 673 set_bit(SPI_INTR, &qca->flags); 674 if (qca->spi_thread) 675 wake_up_process(qca->spi_thread); 676 677 return IRQ_HANDLED; 678 } 679 680 static int 681 qcaspi_netdev_open(struct net_device *dev) 682 { 683 struct qcaspi *qca = netdev_priv(dev); 684 struct task_struct *thread; 685 686 if (!qca) 687 return -EINVAL; 688 689 set_bit(SPI_INTR, &qca->flags); 690 qca->sync = QCASPI_SYNC_UNKNOWN; 691 qcafrm_fsm_init_spi(&qca->frm_handle); 692 693 thread = kthread_run((void *)qcaspi_spi_thread, 694 qca, "%s", dev->name); 695 696 if (IS_ERR(thread)) { 697 netdev_err(dev, "%s: unable to start kernel thread.\n", 698 QCASPI_DRV_NAME); 699 return PTR_ERR(thread); 700 } 701 702 qca->spi_thread = thread; 703 704 enable_irq(qca->spi_dev->irq); 705 706 /* SPI thread takes care of TX queue */ 707 708 return 0; 709 } 710 711 static int 712 qcaspi_netdev_close(struct net_device *dev) 713 { 714 struct qcaspi *qca = netdev_priv(dev); 715 716 netif_stop_queue(dev); 717 718 qcaspi_write_register(qca, SPI_REG_INTR_ENABLE, 0, wr_verify); 719 disable_irq(qca->spi_dev->irq); 720 721 if (qca->spi_thread) { 722 kthread_stop(qca->spi_thread); 723 qca->spi_thread = NULL; 724 } 725 qcaspi_flush_tx_ring(qca); 726 727 return 0; 728 } 729 730 static netdev_tx_t 731 qcaspi_netdev_xmit(struct sk_buff *skb, struct net_device *dev) 732 { 733 u32 frame_len; 734 u8 *ptmp; 735 struct qcaspi *qca = netdev_priv(dev); 736 u16 new_tail; 737 struct sk_buff *tskb; 738 u8 pad_len = 0; 739 740 if (skb->len < QCAFRM_MIN_LEN) 741 pad_len = QCAFRM_MIN_LEN - skb->len; 742 743 if (qca->txr.skb[qca->txr.tail]) { 744 netdev_warn(qca->net_dev, "queue was unexpectedly full!\n"); 745 netif_stop_queue(qca->net_dev); 746 qca->stats.ring_full++; 747 return NETDEV_TX_BUSY; 748 } 749 750 if ((skb_headroom(skb) < QCAFRM_HEADER_LEN) || 751 (skb_tailroom(skb) < QCAFRM_FOOTER_LEN + pad_len)) { 752 tskb = skb_copy_expand(skb, QCAFRM_HEADER_LEN, 753 QCAFRM_FOOTER_LEN + pad_len, GFP_ATOMIC); 754 if (!tskb) { 755 qca->stats.out_of_mem++; 756 return NETDEV_TX_BUSY; 757 } 758 dev_kfree_skb(skb); 759 skb = tskb; 760 } 761 762 frame_len = skb->len + pad_len; 763 764 ptmp = skb_push(skb, QCAFRM_HEADER_LEN); 765 qcafrm_create_header(ptmp, frame_len); 766 767 if (pad_len) { 768 ptmp = skb_put_zero(skb, pad_len); 769 } 770 771 ptmp = skb_put(skb, QCAFRM_FOOTER_LEN); 772 qcafrm_create_footer(ptmp); 773 774 netdev_dbg(qca->net_dev, "Tx-ing packet: Size: 0x%08x\n", 775 skb->len); 776 777 qca->txr.size += skb->len + QCASPI_HW_PKT_LEN; 778 779 new_tail = qca->txr.tail + 1; 780 if (new_tail >= qca->txr.count) 781 new_tail = 0; 782 783 qca->txr.skb[qca->txr.tail] = skb; 784 qca->txr.tail = new_tail; 785 786 if (!qcaspi_tx_ring_has_space(&qca->txr)) { 787 netif_stop_queue(qca->net_dev); 788 qca->stats.ring_full++; 789 } 790 791 netif_trans_update(dev); 792 793 if (qca->spi_thread) 794 wake_up_process(qca->spi_thread); 795 796 return NETDEV_TX_OK; 797 } 798 799 static void 800 qcaspi_netdev_tx_timeout(struct net_device *dev, unsigned int txqueue) 801 { 802 struct qcaspi *qca = netdev_priv(dev); 803 804 netdev_info(qca->net_dev, "Transmit timeout at %ld, latency %ld\n", 805 jiffies, jiffies - dev_trans_start(dev)); 806 qca->net_dev->stats.tx_errors++; 807 /* Trigger tx queue flush and QCA7000 reset */ 808 set_bit(SPI_RESET, &qca->flags); 809 810 if (qca->spi_thread) 811 wake_up_process(qca->spi_thread); 812 } 813 814 static int 815 qcaspi_netdev_init(struct net_device *dev) 816 { 817 struct qcaspi *qca = netdev_priv(dev); 818 819 dev->mtu = QCAFRM_MAX_MTU; 820 dev->type = ARPHRD_ETHER; 821 qca->clkspeed = qcaspi_clkspeed; 822 qca->burst_len = qcaspi_burst_len; 823 qca->spi_thread = NULL; 824 qca->buffer_size = (QCAFRM_MAX_MTU + VLAN_ETH_HLEN + QCAFRM_HEADER_LEN + 825 QCAFRM_FOOTER_LEN + QCASPI_HW_PKT_LEN) * QCASPI_RX_MAX_FRAMES; 826 827 memset(&qca->stats, 0, sizeof(struct qcaspi_stats)); 828 829 qca->rx_buffer = kmalloc(qca->buffer_size, GFP_KERNEL); 830 if (!qca->rx_buffer) 831 return -ENOBUFS; 832 833 qca->rx_skb = netdev_alloc_skb_ip_align(dev, qca->net_dev->mtu + 834 VLAN_ETH_HLEN); 835 if (!qca->rx_skb) { 836 kfree(qca->rx_buffer); 837 netdev_info(qca->net_dev, "Failed to allocate RX sk_buff.\n"); 838 return -ENOBUFS; 839 } 840 841 return 0; 842 } 843 844 static void 845 qcaspi_netdev_uninit(struct net_device *dev) 846 { 847 struct qcaspi *qca = netdev_priv(dev); 848 849 kfree(qca->rx_buffer); 850 qca->buffer_size = 0; 851 dev_kfree_skb(qca->rx_skb); 852 } 853 854 static const struct net_device_ops qcaspi_netdev_ops = { 855 .ndo_init = qcaspi_netdev_init, 856 .ndo_uninit = qcaspi_netdev_uninit, 857 .ndo_open = qcaspi_netdev_open, 858 .ndo_stop = qcaspi_netdev_close, 859 .ndo_start_xmit = qcaspi_netdev_xmit, 860 .ndo_set_mac_address = eth_mac_addr, 861 .ndo_tx_timeout = qcaspi_netdev_tx_timeout, 862 .ndo_validate_addr = eth_validate_addr, 863 }; 864 865 static void 866 qcaspi_netdev_setup(struct net_device *dev) 867 { 868 struct qcaspi *qca = NULL; 869 870 dev->netdev_ops = &qcaspi_netdev_ops; 871 qcaspi_set_ethtool_ops(dev); 872 dev->watchdog_timeo = QCASPI_TX_TIMEOUT; 873 dev->priv_flags &= ~IFF_TX_SKB_SHARING; 874 dev->needed_tailroom = ALIGN(QCAFRM_FOOTER_LEN + QCAFRM_MIN_LEN, 4); 875 dev->needed_headroom = ALIGN(QCAFRM_HEADER_LEN, 4); 876 dev->tx_queue_len = 100; 877 878 /* MTU range: 46 - 1500 */ 879 dev->min_mtu = QCAFRM_MIN_MTU; 880 dev->max_mtu = QCAFRM_MAX_MTU; 881 882 qca = netdev_priv(dev); 883 memset(qca, 0, sizeof(struct qcaspi)); 884 885 memset(&qca->txr, 0, sizeof(qca->txr)); 886 qca->txr.count = QCASPI_TX_RING_MAX_LEN; 887 } 888 889 static const struct of_device_id qca_spi_of_match[] = { 890 { .compatible = "qca,qca7000" }, 891 { /* sentinel */ } 892 }; 893 MODULE_DEVICE_TABLE(of, qca_spi_of_match); 894 895 static int 896 qca_spi_probe(struct spi_device *spi) 897 { 898 struct qcaspi *qca = NULL; 899 struct net_device *qcaspi_devs = NULL; 900 u8 legacy_mode = 0; 901 u16 signature; 902 int ret; 903 904 if (!spi->dev.of_node) { 905 dev_err(&spi->dev, "Missing device tree\n"); 906 return -EINVAL; 907 } 908 909 legacy_mode = of_property_read_bool(spi->dev.of_node, 910 "qca,legacy-mode"); 911 912 if (qcaspi_clkspeed == 0) { 913 if (spi->max_speed_hz) 914 qcaspi_clkspeed = spi->max_speed_hz; 915 else 916 qcaspi_clkspeed = QCASPI_CLK_SPEED; 917 } 918 919 if ((qcaspi_clkspeed < QCASPI_CLK_SPEED_MIN) || 920 (qcaspi_clkspeed > QCASPI_CLK_SPEED_MAX)) { 921 dev_err(&spi->dev, "Invalid clkspeed: %d\n", 922 qcaspi_clkspeed); 923 return -EINVAL; 924 } 925 926 if ((qcaspi_burst_len < QCASPI_BURST_LEN_MIN) || 927 (qcaspi_burst_len > QCASPI_BURST_LEN_MAX)) { 928 dev_err(&spi->dev, "Invalid burst len: %d\n", 929 qcaspi_burst_len); 930 return -EINVAL; 931 } 932 933 if ((qcaspi_pluggable < QCASPI_PLUGGABLE_MIN) || 934 (qcaspi_pluggable > QCASPI_PLUGGABLE_MAX)) { 935 dev_err(&spi->dev, "Invalid pluggable: %d\n", 936 qcaspi_pluggable); 937 return -EINVAL; 938 } 939 940 if (wr_verify < QCASPI_WRITE_VERIFY_MIN || 941 wr_verify > QCASPI_WRITE_VERIFY_MAX) { 942 dev_err(&spi->dev, "Invalid write verify: %d\n", 943 wr_verify); 944 return -EINVAL; 945 } 946 947 dev_info(&spi->dev, "ver=%s, clkspeed=%d, burst_len=%d, pluggable=%d\n", 948 QCASPI_DRV_VERSION, 949 qcaspi_clkspeed, 950 qcaspi_burst_len, 951 qcaspi_pluggable); 952 953 spi->mode = SPI_MODE_3; 954 spi->max_speed_hz = qcaspi_clkspeed; 955 if (spi_setup(spi) < 0) { 956 dev_err(&spi->dev, "Unable to setup SPI device\n"); 957 return -EFAULT; 958 } 959 960 qcaspi_devs = alloc_etherdev(sizeof(struct qcaspi)); 961 if (!qcaspi_devs) 962 return -ENOMEM; 963 964 qcaspi_netdev_setup(qcaspi_devs); 965 SET_NETDEV_DEV(qcaspi_devs, &spi->dev); 966 967 qca = netdev_priv(qcaspi_devs); 968 if (!qca) { 969 free_netdev(qcaspi_devs); 970 dev_err(&spi->dev, "Fail to retrieve private structure\n"); 971 return -ENOMEM; 972 } 973 qca->net_dev = qcaspi_devs; 974 qca->spi_dev = spi; 975 qca->legacy_mode = legacy_mode; 976 977 spi_set_drvdata(spi, qcaspi_devs); 978 979 ret = devm_request_irq(&spi->dev, spi->irq, qcaspi_intr_handler, 980 IRQF_NO_AUTOEN, qca->net_dev->name, qca); 981 if (ret) { 982 dev_err(&spi->dev, "Unable to get IRQ %d (irqval=%d).\n", 983 spi->irq, ret); 984 free_netdev(qcaspi_devs); 985 return ret; 986 } 987 988 ret = of_get_ethdev_address(spi->dev.of_node, qca->net_dev); 989 if (ret) { 990 eth_hw_addr_random(qca->net_dev); 991 dev_info(&spi->dev, "Using random MAC address: %pM\n", 992 qca->net_dev->dev_addr); 993 } 994 995 netif_carrier_off(qca->net_dev); 996 997 if (!qcaspi_pluggable) { 998 qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature); 999 qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature); 1000 1001 if (signature != QCASPI_GOOD_SIGNATURE) { 1002 dev_err(&spi->dev, "Invalid signature (expected 0x%04x, read 0x%04x)\n", 1003 QCASPI_GOOD_SIGNATURE, signature); 1004 free_netdev(qcaspi_devs); 1005 return -EFAULT; 1006 } 1007 } 1008 1009 if (register_netdev(qcaspi_devs)) { 1010 dev_err(&spi->dev, "Unable to register net device %s\n", 1011 qcaspi_devs->name); 1012 free_netdev(qcaspi_devs); 1013 return -EFAULT; 1014 } 1015 1016 qcaspi_init_device_debugfs(qca); 1017 1018 return 0; 1019 } 1020 1021 static void 1022 qca_spi_remove(struct spi_device *spi) 1023 { 1024 struct net_device *qcaspi_devs = spi_get_drvdata(spi); 1025 struct qcaspi *qca = netdev_priv(qcaspi_devs); 1026 1027 qcaspi_remove_device_debugfs(qca); 1028 1029 unregister_netdev(qcaspi_devs); 1030 free_netdev(qcaspi_devs); 1031 } 1032 1033 static const struct spi_device_id qca_spi_id[] = { 1034 { "qca7000", 0 }, 1035 { /* sentinel */ } 1036 }; 1037 MODULE_DEVICE_TABLE(spi, qca_spi_id); 1038 1039 static struct spi_driver qca_spi_driver = { 1040 .driver = { 1041 .name = QCASPI_DRV_NAME, 1042 .of_match_table = qca_spi_of_match, 1043 }, 1044 .id_table = qca_spi_id, 1045 .probe = qca_spi_probe, 1046 .remove = qca_spi_remove, 1047 }; 1048 module_spi_driver(qca_spi_driver); 1049 1050 MODULE_DESCRIPTION("Qualcomm Atheros QCA7000 SPI Driver"); 1051 MODULE_AUTHOR("Qualcomm Atheros Communications"); 1052 MODULE_AUTHOR("Stefan Wahren <wahrenst@gmx.net>"); 1053 MODULE_LICENSE("Dual BSD/GPL"); 1054 MODULE_VERSION(QCASPI_DRV_VERSION); 1055