blob: f66641d961e3bc18ae15a301323497ff9fb265e8 [file] [log] [blame]
Stefan Wahren291ab062014-09-26 22:21:21 +00001/*
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>
Stefan Wahren291ab062014-09-26 22:21:21 +000044
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
56static int qcaspi_clkspeed;
57module_param(qcaspi_clkspeed, int, 0);
58MODULE_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
62static int qcaspi_burst_len = MAX_DMA_BURST_LEN;
63module_param(qcaspi_burst_len, int, 0);
64MODULE_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
68static int qcaspi_pluggable = QCASPI_PLUGGABLE_MIN;
69module_param(qcaspi_pluggable, int, 0);
70MODULE_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
76static void
77start_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
86static void
87end_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
99static u32
100qcaspi_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
126static u32
127qcaspi_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
147static u32
148qcaspi_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
174static u32
175qcaspi_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
195static int
196qcaspi_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
235static int
236qcaspi_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
288static int
289qcaspi_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
399static int
400qcaspi_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
412static void
413qcaspi_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
434static void
435qcaspi_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
509static int
510qcaspi_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
Joe Perchesdbedd442015-03-06 20:49:12 -0800573 * if sync has occurred
Stefan Wahren291ab062014-09-26 22:21:21 +0000574 */
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
592static irqreturn_t
593qcaspi_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
605int
606qcaspi_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
642int
643qcaspi_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
659static netdev_tx_t
660qcaspi_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 dev->trans_start = jiffies;
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
731static void
732qcaspi_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);
738 qca->net_dev->stats.tx_errors++;
739 /* wake the queue if there is room */
740 if (qcaspi_tx_ring_has_space(&qca->txr))
741 netif_wake_queue(dev);
742}
743
744static int
745qcaspi_netdev_init(struct net_device *dev)
746{
747 struct qcaspi *qca = netdev_priv(dev);
748
749 dev->mtu = QCASPI_MTU;
750 dev->type = ARPHRD_ETHER;
751 qca->clkspeed = qcaspi_clkspeed;
752 qca->burst_len = qcaspi_burst_len;
753 qca->spi_thread = NULL;
754 qca->buffer_size = (dev->mtu + VLAN_ETH_HLEN + QCAFRM_HEADER_LEN +
755 QCAFRM_FOOTER_LEN + 4) * 4;
756
757 memset(&qca->stats, 0, sizeof(struct qcaspi_stats));
758
759 qca->rx_buffer = kmalloc(qca->buffer_size, GFP_KERNEL);
760 if (!qca->rx_buffer)
761 return -ENOBUFS;
762
763 qca->rx_skb = netdev_alloc_skb(dev, qca->net_dev->mtu + VLAN_ETH_HLEN);
764 if (!qca->rx_skb) {
765 kfree(qca->rx_buffer);
766 netdev_info(qca->net_dev, "Failed to allocate RX sk_buff.\n");
767 return -ENOBUFS;
768 }
769
770 return 0;
771}
772
773static void
774qcaspi_netdev_uninit(struct net_device *dev)
775{
776 struct qcaspi *qca = netdev_priv(dev);
777
778 kfree(qca->rx_buffer);
779 qca->buffer_size = 0;
780 if (qca->rx_skb)
781 dev_kfree_skb(qca->rx_skb);
782}
783
784static int
785qcaspi_netdev_change_mtu(struct net_device *dev, int new_mtu)
786{
787 if ((new_mtu < QCAFRM_ETHMINMTU) || (new_mtu > QCAFRM_ETHMAXMTU))
788 return -EINVAL;
789
790 dev->mtu = new_mtu;
791
792 return 0;
793}
794
795static const struct net_device_ops qcaspi_netdev_ops = {
796 .ndo_init = qcaspi_netdev_init,
797 .ndo_uninit = qcaspi_netdev_uninit,
798 .ndo_open = qcaspi_netdev_open,
799 .ndo_stop = qcaspi_netdev_close,
800 .ndo_start_xmit = qcaspi_netdev_xmit,
801 .ndo_change_mtu = qcaspi_netdev_change_mtu,
802 .ndo_set_mac_address = eth_mac_addr,
803 .ndo_tx_timeout = qcaspi_netdev_tx_timeout,
804 .ndo_validate_addr = eth_validate_addr,
805};
806
807static void
808qcaspi_netdev_setup(struct net_device *dev)
809{
810 struct qcaspi *qca = NULL;
811
Stefan Wahren291ab062014-09-26 22:21:21 +0000812 dev->netdev_ops = &qcaspi_netdev_ops;
813 qcaspi_set_ethtool_ops(dev);
814 dev->watchdog_timeo = QCASPI_TX_TIMEOUT;
815 dev->flags = IFF_MULTICAST;
816 dev->tx_queue_len = 100;
817
818 qca = netdev_priv(dev);
819 memset(qca, 0, sizeof(struct qcaspi));
820
821 memset(&qca->spi_xfer1, 0, sizeof(struct spi_transfer));
822 memset(&qca->spi_xfer2, 0, sizeof(struct spi_transfer) * 2);
823
824 spi_message_init(&qca->spi_msg1);
825 spi_message_add_tail(&qca->spi_xfer1, &qca->spi_msg1);
826
827 spi_message_init(&qca->spi_msg2);
828 spi_message_add_tail(&qca->spi_xfer2[0], &qca->spi_msg2);
829 spi_message_add_tail(&qca->spi_xfer2[1], &qca->spi_msg2);
830
831 memset(&qca->txr, 0, sizeof(qca->txr));
832 qca->txr.count = TX_RING_MAX_LEN;
833}
834
835static const struct of_device_id qca_spi_of_match[] = {
836 { .compatible = "qca,qca7000" },
837 { /* sentinel */ }
838};
839MODULE_DEVICE_TABLE(of, qca_spi_of_match);
840
841static int
842qca_spi_probe(struct spi_device *spi_device)
843{
844 struct qcaspi *qca = NULL;
845 struct net_device *qcaspi_devs = NULL;
846 u8 legacy_mode = 0;
847 u16 signature;
848 const char *mac;
849
850 if (!spi_device->dev.of_node) {
851 dev_err(&spi_device->dev, "Missing device tree\n");
852 return -EINVAL;
853 }
854
855 legacy_mode = of_property_read_bool(spi_device->dev.of_node,
856 "qca,legacy-mode");
857
858 if (qcaspi_clkspeed == 0) {
859 if (spi_device->max_speed_hz)
860 qcaspi_clkspeed = spi_device->max_speed_hz;
861 else
862 qcaspi_clkspeed = QCASPI_CLK_SPEED;
863 }
864
865 if ((qcaspi_clkspeed < QCASPI_CLK_SPEED_MIN) ||
866 (qcaspi_clkspeed > QCASPI_CLK_SPEED_MAX)) {
867 dev_info(&spi_device->dev, "Invalid clkspeed: %d\n",
868 qcaspi_clkspeed);
869 return -EINVAL;
870 }
871
872 if ((qcaspi_burst_len < QCASPI_BURST_LEN_MIN) ||
873 (qcaspi_burst_len > QCASPI_BURST_LEN_MAX)) {
874 dev_info(&spi_device->dev, "Invalid burst len: %d\n",
875 qcaspi_burst_len);
876 return -EINVAL;
877 }
878
879 if ((qcaspi_pluggable < QCASPI_PLUGGABLE_MIN) ||
880 (qcaspi_pluggable > QCASPI_PLUGGABLE_MAX)) {
881 dev_info(&spi_device->dev, "Invalid pluggable: %d\n",
882 qcaspi_pluggable);
883 return -EINVAL;
884 }
885
886 dev_info(&spi_device->dev, "ver=%s, clkspeed=%d, burst_len=%d, pluggable=%d\n",
887 QCASPI_DRV_VERSION,
888 qcaspi_clkspeed,
889 qcaspi_burst_len,
890 qcaspi_pluggable);
891
892 spi_device->mode = SPI_MODE_3;
893 spi_device->max_speed_hz = qcaspi_clkspeed;
894 if (spi_setup(spi_device) < 0) {
895 dev_err(&spi_device->dev, "Unable to setup SPI device\n");
896 return -EFAULT;
897 }
898
899 qcaspi_devs = alloc_etherdev(sizeof(struct qcaspi));
900 if (!qcaspi_devs)
901 return -ENOMEM;
902
903 qcaspi_netdev_setup(qcaspi_devs);
904
905 qca = netdev_priv(qcaspi_devs);
906 if (!qca) {
907 free_netdev(qcaspi_devs);
908 dev_err(&spi_device->dev, "Fail to retrieve private structure\n");
909 return -ENOMEM;
910 }
911 qca->net_dev = qcaspi_devs;
912 qca->spi_dev = spi_device;
913 qca->legacy_mode = legacy_mode;
914
915 mac = of_get_mac_address(spi_device->dev.of_node);
916
917 if (mac)
918 ether_addr_copy(qca->net_dev->dev_addr, mac);
919
920 if (!is_valid_ether_addr(qca->net_dev->dev_addr)) {
921 eth_hw_addr_random(qca->net_dev);
922 dev_info(&spi_device->dev, "Using random MAC address: %pM\n",
923 qca->net_dev->dev_addr);
924 }
925
926 netif_carrier_off(qca->net_dev);
927
928 if (!qcaspi_pluggable) {
929 qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature);
930 qcaspi_read_register(qca, SPI_REG_SIGNATURE, &signature);
931
932 if (signature != QCASPI_GOOD_SIGNATURE) {
933 dev_err(&spi_device->dev, "Invalid signature (0x%04X)\n",
934 signature);
935 free_netdev(qcaspi_devs);
936 return -EFAULT;
937 }
938 }
939
940 if (register_netdev(qcaspi_devs)) {
941 dev_info(&spi_device->dev, "Unable to register net device %s\n",
942 qcaspi_devs->name);
943 free_netdev(qcaspi_devs);
944 return -EFAULT;
945 }
946
947 spi_set_drvdata(spi_device, qcaspi_devs);
948
949 qcaspi_init_device_debugfs(qca);
950
951 return 0;
952}
953
954static int
955qca_spi_remove(struct spi_device *spi_device)
956{
957 struct net_device *qcaspi_devs = spi_get_drvdata(spi_device);
958 struct qcaspi *qca = netdev_priv(qcaspi_devs);
959
960 qcaspi_remove_device_debugfs(qca);
961
962 unregister_netdev(qcaspi_devs);
963 free_netdev(qcaspi_devs);
964
965 return 0;
966}
967
968static const struct spi_device_id qca_spi_id[] = {
969 { "qca7000", 0 },
970 { /* sentinel */ }
971};
972MODULE_DEVICE_TABLE(spi, qca_spi_id);
973
974static struct spi_driver qca_spi_driver = {
975 .driver = {
976 .name = QCASPI_DRV_NAME,
977 .owner = THIS_MODULE,
978 .of_match_table = qca_spi_of_match,
979 },
980 .id_table = qca_spi_id,
981 .probe = qca_spi_probe,
982 .remove = qca_spi_remove,
983};
984module_spi_driver(qca_spi_driver);
985
986MODULE_DESCRIPTION("Qualcomm Atheros SPI Driver");
987MODULE_AUTHOR("Qualcomm Atheros Communications");
988MODULE_AUTHOR("Stefan Wahren <stefan.wahren@i2se.com>");
989MODULE_LICENSE("Dual BSD/GPL");
990MODULE_VERSION(QCASPI_DRV_VERSION);