1 /*
2 * drivers/net/ethernet/ec_bhf.c
3 *
4 * Copyright (C) 2014 Darek Marcinkiewicz <reksio@newterm.pl>
5 *
6 * This software is licensed under the terms of the GNU General Public
7 * License version 2, as published by the Free Software Foundation, and
8 * may be copied, distributed, and modified under those terms.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 */
16
17 /* This is a driver for EtherCAT master module present on CCAT FPGA.
18 * Those can be found on Bechhoff CX50xx industrial PCs.
19 */
20
21 #include <linux/kernel.h>
22 #include <linux/module.h>
23 #include <linux/moduleparam.h>
24 #include <linux/pci.h>
25 #include <linux/init.h>
26
27 #include <linux/netdevice.h>
28 #include <linux/etherdevice.h>
29 #include <linux/ip.h>
30 #include <linux/skbuff.h>
31 #include <linux/hrtimer.h>
32 #include <linux/interrupt.h>
33 #include <linux/stat.h>
34
35 #define TIMER_INTERVAL_NSEC 20000
36
37 #define INFO_BLOCK_SIZE 0x10
38 #define INFO_BLOCK_TYPE 0x0
39 #define INFO_BLOCK_REV 0x2
40 #define INFO_BLOCK_BLK_CNT 0x4
41 #define INFO_BLOCK_TX_CHAN 0x4
42 #define INFO_BLOCK_RX_CHAN 0x5
43 #define INFO_BLOCK_OFFSET 0x8
44
45 #define EC_MII_OFFSET 0x4
46 #define EC_FIFO_OFFSET 0x8
47 #define EC_MAC_OFFSET 0xc
48
49 #define MAC_FRAME_ERR_CNT 0x0
50 #define MAC_RX_ERR_CNT 0x1
51 #define MAC_CRC_ERR_CNT 0x2
52 #define MAC_LNK_LST_ERR_CNT 0x3
53 #define MAC_TX_FRAME_CNT 0x10
54 #define MAC_RX_FRAME_CNT 0x14
55 #define MAC_TX_FIFO_LVL 0x20
56 #define MAC_DROPPED_FRMS 0x28
57 #define MAC_CONNECTED_CCAT_FLAG 0x78
58
59 #define MII_MAC_ADDR 0x8
60 #define MII_MAC_FILT_FLAG 0xe
61 #define MII_LINK_STATUS 0xf
62
63 #define FIFO_TX_REG 0x0
64 #define FIFO_TX_RESET 0x8
65 #define FIFO_RX_REG 0x10
66 #define FIFO_RX_ADDR_VALID (1u << 31)
67 #define FIFO_RX_RESET 0x18
68
69 #define DMA_CHAN_OFFSET 0x1000
70 #define DMA_CHAN_SIZE 0x8
71
72 #define DMA_WINDOW_SIZE_MASK 0xfffffffc
73
74 #define ETHERCAT_MASTER_ID 0x14
75
76 static const struct pci_device_id ids[] = {
77 { PCI_DEVICE(0x15ec, 0x5000), },
78 { 0, }
79 };
80 MODULE_DEVICE_TABLE(pci, ids);
81
82 struct rx_header {
83 #define RXHDR_NEXT_ADDR_MASK 0xffffffu
84 #define RXHDR_NEXT_VALID (1u << 31)
85 __le32 next;
86 #define RXHDR_NEXT_RECV_FLAG 0x1
87 __le32 recv;
88 #define RXHDR_LEN_MASK 0xfffu
89 __le16 len;
90 __le16 port;
91 __le32 reserved;
92 u8 timestamp[8];
93 } __packed;
94
95 #define PKT_PAYLOAD_SIZE 0x7e8
96 struct rx_desc {
97 struct rx_header header;
98 u8 data[PKT_PAYLOAD_SIZE];
99 } __packed;
100
101 struct tx_header {
102 __le16 len;
103 #define TX_HDR_PORT_0 0x1
104 #define TX_HDR_PORT_1 0x2
105 u8 port;
106 u8 ts_enable;
107 #define TX_HDR_SENT 0x1
108 __le32 sent;
109 u8 timestamp[8];
110 } __packed;
111
112 struct tx_desc {
113 struct tx_header header;
114 u8 data[PKT_PAYLOAD_SIZE];
115 } __packed;
116
117 #define FIFO_SIZE 64
118
119 static long polling_frequency = TIMER_INTERVAL_NSEC;
120
121 struct bhf_dma {
122 u8 *buf;
123 size_t len;
124 dma_addr_t buf_phys;
125
126 u8 *alloc;
127 size_t alloc_len;
128 dma_addr_t alloc_phys;
129 };
130
131 struct ec_bhf_priv {
132 struct net_device *net_dev;
133 struct pci_dev *dev;
134
135 void __iomem *io;
136 void __iomem *dma_io;
137
138 struct hrtimer hrtimer;
139
140 int tx_dma_chan;
141 int rx_dma_chan;
142 void __iomem *ec_io;
143 void __iomem *fifo_io;
144 void __iomem *mii_io;
145 void __iomem *mac_io;
146
147 struct bhf_dma rx_buf;
148 struct rx_desc *rx_descs;
149 int rx_dnext;
150 int rx_dcount;
151
152 struct bhf_dma tx_buf;
153 struct tx_desc *tx_descs;
154 int tx_dcount;
155 int tx_dnext;
156
157 u64 stat_rx_bytes;
158 u64 stat_tx_bytes;
159 };
160
161 #define PRIV_TO_DEV(priv) (&(priv)->dev->dev)
162
ec_bhf_reset(struct ec_bhf_priv * priv)163 static void ec_bhf_reset(struct ec_bhf_priv *priv)
164 {
165 iowrite8(0, priv->mac_io + MAC_FRAME_ERR_CNT);
166 iowrite8(0, priv->mac_io + MAC_RX_ERR_CNT);
167 iowrite8(0, priv->mac_io + MAC_CRC_ERR_CNT);
168 iowrite8(0, priv->mac_io + MAC_LNK_LST_ERR_CNT);
169 iowrite32(0, priv->mac_io + MAC_TX_FRAME_CNT);
170 iowrite32(0, priv->mac_io + MAC_RX_FRAME_CNT);
171 iowrite8(0, priv->mac_io + MAC_DROPPED_FRMS);
172
173 iowrite8(0, priv->fifo_io + FIFO_TX_RESET);
174 iowrite8(0, priv->fifo_io + FIFO_RX_RESET);
175
176 iowrite8(0, priv->mac_io + MAC_TX_FIFO_LVL);
177 }
178
ec_bhf_send_packet(struct ec_bhf_priv * priv,struct tx_desc * desc)179 static void ec_bhf_send_packet(struct ec_bhf_priv *priv, struct tx_desc *desc)
180 {
181 u32 len = le16_to_cpu(desc->header.len) + sizeof(desc->header);
182 u32 addr = (u8 *)desc - priv->tx_buf.buf;
183
184 iowrite32((ALIGN(len, 8) << 24) | addr, priv->fifo_io + FIFO_TX_REG);
185 }
186
ec_bhf_desc_sent(struct tx_desc * desc)187 static int ec_bhf_desc_sent(struct tx_desc *desc)
188 {
189 return le32_to_cpu(desc->header.sent) & TX_HDR_SENT;
190 }
191
ec_bhf_process_tx(struct ec_bhf_priv * priv)192 static void ec_bhf_process_tx(struct ec_bhf_priv *priv)
193 {
194 if (unlikely(netif_queue_stopped(priv->net_dev))) {
195 /* Make sure that we perceive changes to tx_dnext. */
196 smp_rmb();
197
198 if (ec_bhf_desc_sent(&priv->tx_descs[priv->tx_dnext]))
199 netif_wake_queue(priv->net_dev);
200 }
201 }
202
ec_bhf_pkt_received(struct rx_desc * desc)203 static int ec_bhf_pkt_received(struct rx_desc *desc)
204 {
205 return le32_to_cpu(desc->header.recv) & RXHDR_NEXT_RECV_FLAG;
206 }
207
ec_bhf_add_rx_desc(struct ec_bhf_priv * priv,struct rx_desc * desc)208 static void ec_bhf_add_rx_desc(struct ec_bhf_priv *priv, struct rx_desc *desc)
209 {
210 iowrite32(FIFO_RX_ADDR_VALID | ((u8 *)(desc) - priv->rx_buf.buf),
211 priv->fifo_io + FIFO_RX_REG);
212 }
213
ec_bhf_process_rx(struct ec_bhf_priv * priv)214 static void ec_bhf_process_rx(struct ec_bhf_priv *priv)
215 {
216 struct rx_desc *desc = &priv->rx_descs[priv->rx_dnext];
217
218 while (ec_bhf_pkt_received(desc)) {
219 int pkt_size = (le16_to_cpu(desc->header.len) &
220 RXHDR_LEN_MASK) - sizeof(struct rx_header) - 4;
221 u8 *data = desc->data;
222 struct sk_buff *skb;
223
224 skb = netdev_alloc_skb_ip_align(priv->net_dev, pkt_size);
225 if (skb) {
226 skb_put_data(skb, data, pkt_size);
227 skb->protocol = eth_type_trans(skb, priv->net_dev);
228 priv->stat_rx_bytes += pkt_size;
229
230 netif_rx(skb);
231 } else {
232 dev_err_ratelimited(PRIV_TO_DEV(priv),
233 "Couldn't allocate a skb_buff for a packet of size %u\n",
234 pkt_size);
235 }
236
237 desc->header.recv = 0;
238
239 ec_bhf_add_rx_desc(priv, desc);
240
241 priv->rx_dnext = (priv->rx_dnext + 1) % priv->rx_dcount;
242 desc = &priv->rx_descs[priv->rx_dnext];
243 }
244 }
245
ec_bhf_timer_fun(struct hrtimer * timer)246 static enum hrtimer_restart ec_bhf_timer_fun(struct hrtimer *timer)
247 {
248 struct ec_bhf_priv *priv = container_of(timer, struct ec_bhf_priv,
249 hrtimer);
250 ec_bhf_process_rx(priv);
251 ec_bhf_process_tx(priv);
252
253 if (!netif_running(priv->net_dev))
254 return HRTIMER_NORESTART;
255
256 hrtimer_forward_now(timer, polling_frequency);
257 return HRTIMER_RESTART;
258 }
259
ec_bhf_setup_offsets(struct ec_bhf_priv * priv)260 static int ec_bhf_setup_offsets(struct ec_bhf_priv *priv)
261 {
262 struct device *dev = PRIV_TO_DEV(priv);
263 unsigned block_count, i;
264 void __iomem *ec_info;
265
266 block_count = ioread8(priv->io + INFO_BLOCK_BLK_CNT);
267 for (i = 0; i < block_count; i++) {
268 u16 type = ioread16(priv->io + i * INFO_BLOCK_SIZE +
269 INFO_BLOCK_TYPE);
270 if (type == ETHERCAT_MASTER_ID)
271 break;
272 }
273 if (i == block_count) {
274 dev_err(dev, "EtherCAT master with DMA block not found\n");
275 return -ENODEV;
276 }
277
278 ec_info = priv->io + i * INFO_BLOCK_SIZE;
279
280 priv->tx_dma_chan = ioread8(ec_info + INFO_BLOCK_TX_CHAN);
281 priv->rx_dma_chan = ioread8(ec_info + INFO_BLOCK_RX_CHAN);
282
283 priv->ec_io = priv->io + ioread32(ec_info + INFO_BLOCK_OFFSET);
284 priv->mii_io = priv->ec_io + ioread32(priv->ec_io + EC_MII_OFFSET);
285 priv->fifo_io = priv->ec_io + ioread32(priv->ec_io + EC_FIFO_OFFSET);
286 priv->mac_io = priv->ec_io + ioread32(priv->ec_io + EC_MAC_OFFSET);
287
288 return 0;
289 }
290
ec_bhf_start_xmit(struct sk_buff * skb,struct net_device * net_dev)291 static netdev_tx_t ec_bhf_start_xmit(struct sk_buff *skb,
292 struct net_device *net_dev)
293 {
294 struct ec_bhf_priv *priv = netdev_priv(net_dev);
295 struct tx_desc *desc;
296 unsigned len;
297
298 desc = &priv->tx_descs[priv->tx_dnext];
299
300 skb_copy_and_csum_dev(skb, desc->data);
301 len = skb->len;
302
303 memset(&desc->header, 0, sizeof(desc->header));
304 desc->header.len = cpu_to_le16(len);
305 desc->header.port = TX_HDR_PORT_0;
306
307 ec_bhf_send_packet(priv, desc);
308
309 priv->tx_dnext = (priv->tx_dnext + 1) % priv->tx_dcount;
310
311 if (!ec_bhf_desc_sent(&priv->tx_descs[priv->tx_dnext])) {
312 /* Make sure that updates to tx_dnext are perceived
313 * by timer routine.
314 */
315 smp_wmb();
316
317 netif_stop_queue(net_dev);
318 }
319
320 priv->stat_tx_bytes += len;
321
322 dev_kfree_skb(skb);
323
324 return NETDEV_TX_OK;
325 }
326
ec_bhf_alloc_dma_mem(struct ec_bhf_priv * priv,struct bhf_dma * buf,int channel,int size)327 static int ec_bhf_alloc_dma_mem(struct ec_bhf_priv *priv,
328 struct bhf_dma *buf,
329 int channel,
330 int size)
331 {
332 int offset = channel * DMA_CHAN_SIZE + DMA_CHAN_OFFSET;
333 struct device *dev = PRIV_TO_DEV(priv);
334 u32 mask;
335
336 iowrite32(0xffffffff, priv->dma_io + offset);
337
338 mask = ioread32(priv->dma_io + offset);
339 mask &= DMA_WINDOW_SIZE_MASK;
340
341 /* We want to allocate a chunk of memory that is:
342 * - aligned to the mask we just read
343 * - is of size 2^mask bytes (at most)
344 * In order to ensure that we will allocate buffer of
345 * 2 * 2^mask bytes.
346 */
347 buf->len = min_t(int, ~mask + 1, size);
348 buf->alloc_len = 2 * buf->len;
349
350 buf->alloc = dma_alloc_coherent(dev, buf->alloc_len, &buf->alloc_phys,
351 GFP_KERNEL);
352 if (buf->alloc == NULL) {
353 dev_err(dev, "Failed to allocate buffer\n");
354 return -ENOMEM;
355 }
356
357 buf->buf_phys = (buf->alloc_phys + buf->len) & mask;
358 buf->buf = buf->alloc + (buf->buf_phys - buf->alloc_phys);
359
360 iowrite32(0, priv->dma_io + offset + 4);
361 iowrite32(buf->buf_phys, priv->dma_io + offset);
362
363 return 0;
364 }
365
ec_bhf_setup_tx_descs(struct ec_bhf_priv * priv)366 static void ec_bhf_setup_tx_descs(struct ec_bhf_priv *priv)
367 {
368 int i = 0;
369
370 priv->tx_dcount = priv->tx_buf.len / sizeof(struct tx_desc);
371 priv->tx_descs = (struct tx_desc *)priv->tx_buf.buf;
372 priv->tx_dnext = 0;
373
374 for (i = 0; i < priv->tx_dcount; i++)
375 priv->tx_descs[i].header.sent = cpu_to_le32(TX_HDR_SENT);
376 }
377
ec_bhf_setup_rx_descs(struct ec_bhf_priv * priv)378 static void ec_bhf_setup_rx_descs(struct ec_bhf_priv *priv)
379 {
380 int i;
381
382 priv->rx_dcount = priv->rx_buf.len / sizeof(struct rx_desc);
383 priv->rx_descs = (struct rx_desc *)priv->rx_buf.buf;
384 priv->rx_dnext = 0;
385
386 for (i = 0; i < priv->rx_dcount; i++) {
387 struct rx_desc *desc = &priv->rx_descs[i];
388 u32 next;
389
390 if (i != priv->rx_dcount - 1)
391 next = (u8 *)(desc + 1) - priv->rx_buf.buf;
392 else
393 next = 0;
394 next |= RXHDR_NEXT_VALID;
395 desc->header.next = cpu_to_le32(next);
396 desc->header.recv = 0;
397 ec_bhf_add_rx_desc(priv, desc);
398 }
399 }
400
ec_bhf_open(struct net_device * net_dev)401 static int ec_bhf_open(struct net_device *net_dev)
402 {
403 struct ec_bhf_priv *priv = netdev_priv(net_dev);
404 struct device *dev = PRIV_TO_DEV(priv);
405 int err = 0;
406
407 ec_bhf_reset(priv);
408
409 err = ec_bhf_alloc_dma_mem(priv, &priv->rx_buf, priv->rx_dma_chan,
410 FIFO_SIZE * sizeof(struct rx_desc));
411 if (err) {
412 dev_err(dev, "Failed to allocate rx buffer\n");
413 goto out;
414 }
415 ec_bhf_setup_rx_descs(priv);
416
417 err = ec_bhf_alloc_dma_mem(priv, &priv->tx_buf, priv->tx_dma_chan,
418 FIFO_SIZE * sizeof(struct tx_desc));
419 if (err) {
420 dev_err(dev, "Failed to allocate tx buffer\n");
421 goto error_rx_free;
422 }
423 iowrite8(0, priv->mii_io + MII_MAC_FILT_FLAG);
424 ec_bhf_setup_tx_descs(priv);
425
426 netif_start_queue(net_dev);
427
428 hrtimer_init(&priv->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
429 priv->hrtimer.function = ec_bhf_timer_fun;
430 hrtimer_start(&priv->hrtimer, polling_frequency, HRTIMER_MODE_REL);
431
432 return 0;
433
434 error_rx_free:
435 dma_free_coherent(dev, priv->rx_buf.alloc_len, priv->rx_buf.alloc,
436 priv->rx_buf.alloc_len);
437 out:
438 return err;
439 }
440
ec_bhf_stop(struct net_device * net_dev)441 static int ec_bhf_stop(struct net_device *net_dev)
442 {
443 struct ec_bhf_priv *priv = netdev_priv(net_dev);
444 struct device *dev = PRIV_TO_DEV(priv);
445
446 hrtimer_cancel(&priv->hrtimer);
447
448 ec_bhf_reset(priv);
449
450 netif_tx_disable(net_dev);
451
452 dma_free_coherent(dev, priv->tx_buf.alloc_len,
453 priv->tx_buf.alloc, priv->tx_buf.alloc_phys);
454 dma_free_coherent(dev, priv->rx_buf.alloc_len,
455 priv->rx_buf.alloc, priv->rx_buf.alloc_phys);
456
457 return 0;
458 }
459
460 static void
ec_bhf_get_stats(struct net_device * net_dev,struct rtnl_link_stats64 * stats)461 ec_bhf_get_stats(struct net_device *net_dev,
462 struct rtnl_link_stats64 *stats)
463 {
464 struct ec_bhf_priv *priv = netdev_priv(net_dev);
465
466 stats->rx_errors = ioread8(priv->mac_io + MAC_RX_ERR_CNT) +
467 ioread8(priv->mac_io + MAC_CRC_ERR_CNT) +
468 ioread8(priv->mac_io + MAC_FRAME_ERR_CNT);
469 stats->rx_packets = ioread32(priv->mac_io + MAC_RX_FRAME_CNT);
470 stats->tx_packets = ioread32(priv->mac_io + MAC_TX_FRAME_CNT);
471 stats->rx_dropped = ioread8(priv->mac_io + MAC_DROPPED_FRMS);
472
473 stats->tx_bytes = priv->stat_tx_bytes;
474 stats->rx_bytes = priv->stat_rx_bytes;
475 }
476
477 static const struct net_device_ops ec_bhf_netdev_ops = {
478 .ndo_start_xmit = ec_bhf_start_xmit,
479 .ndo_open = ec_bhf_open,
480 .ndo_stop = ec_bhf_stop,
481 .ndo_get_stats64 = ec_bhf_get_stats,
482 .ndo_validate_addr = eth_validate_addr,
483 .ndo_set_mac_address = eth_mac_addr
484 };
485
ec_bhf_probe(struct pci_dev * dev,const struct pci_device_id * id)486 static int ec_bhf_probe(struct pci_dev *dev, const struct pci_device_id *id)
487 {
488 struct net_device *net_dev;
489 struct ec_bhf_priv *priv;
490 void __iomem *dma_io;
491 void __iomem *io;
492 int err = 0;
493
494 err = pci_enable_device(dev);
495 if (err)
496 return err;
497
498 pci_set_master(dev);
499
500 err = pci_set_dma_mask(dev, DMA_BIT_MASK(32));
501 if (err) {
502 dev_err(&dev->dev,
503 "Required dma mask not supported, failed to initialize device\n");
504 err = -EIO;
505 goto err_disable_dev;
506 }
507
508 err = pci_set_consistent_dma_mask(dev, DMA_BIT_MASK(32));
509 if (err) {
510 dev_err(&dev->dev,
511 "Required dma mask not supported, failed to initialize device\n");
512 goto err_disable_dev;
513 }
514
515 err = pci_request_regions(dev, "ec_bhf");
516 if (err) {
517 dev_err(&dev->dev, "Failed to request pci memory regions\n");
518 goto err_disable_dev;
519 }
520
521 io = pci_iomap(dev, 0, 0);
522 if (!io) {
523 dev_err(&dev->dev, "Failed to map pci card memory bar 0");
524 err = -EIO;
525 goto err_release_regions;
526 }
527
528 dma_io = pci_iomap(dev, 2, 0);
529 if (!dma_io) {
530 dev_err(&dev->dev, "Failed to map pci card memory bar 2");
531 err = -EIO;
532 goto err_unmap;
533 }
534
535 net_dev = alloc_etherdev(sizeof(struct ec_bhf_priv));
536 if (net_dev == NULL) {
537 err = -ENOMEM;
538 goto err_unmap_dma_io;
539 }
540
541 pci_set_drvdata(dev, net_dev);
542 SET_NETDEV_DEV(net_dev, &dev->dev);
543
544 net_dev->features = 0;
545 net_dev->flags |= IFF_NOARP;
546
547 net_dev->netdev_ops = &ec_bhf_netdev_ops;
548
549 priv = netdev_priv(net_dev);
550 priv->net_dev = net_dev;
551 priv->io = io;
552 priv->dma_io = dma_io;
553 priv->dev = dev;
554
555 err = ec_bhf_setup_offsets(priv);
556 if (err < 0)
557 goto err_free_net_dev;
558
559 memcpy_fromio(net_dev->dev_addr, priv->mii_io + MII_MAC_ADDR, 6);
560
561 err = register_netdev(net_dev);
562 if (err < 0)
563 goto err_free_net_dev;
564
565 return 0;
566
567 err_free_net_dev:
568 free_netdev(net_dev);
569 err_unmap_dma_io:
570 pci_iounmap(dev, dma_io);
571 err_unmap:
572 pci_iounmap(dev, io);
573 err_release_regions:
574 pci_release_regions(dev);
575 err_disable_dev:
576 pci_clear_master(dev);
577 pci_disable_device(dev);
578
579 return err;
580 }
581
ec_bhf_remove(struct pci_dev * dev)582 static void ec_bhf_remove(struct pci_dev *dev)
583 {
584 struct net_device *net_dev = pci_get_drvdata(dev);
585 struct ec_bhf_priv *priv = netdev_priv(net_dev);
586
587 unregister_netdev(net_dev);
588 free_netdev(net_dev);
589
590 pci_iounmap(dev, priv->dma_io);
591 pci_iounmap(dev, priv->io);
592 pci_release_regions(dev);
593 pci_clear_master(dev);
594 pci_disable_device(dev);
595 }
596
597 static struct pci_driver pci_driver = {
598 .name = "ec_bhf",
599 .id_table = ids,
600 .probe = ec_bhf_probe,
601 .remove = ec_bhf_remove,
602 };
603 module_pci_driver(pci_driver);
604
605 module_param(polling_frequency, long, 0444);
606 MODULE_PARM_DESC(polling_frequency, "Polling timer frequency in ns");
607
608 MODULE_LICENSE("GPL");
609 MODULE_AUTHOR("Dariusz Marcinkiewicz <reksio@newterm.pl>");
610
