GNU Linux-libre 4.19.264-gnu1
[releases.git] / drivers / net / ethernet / moxa / moxart_ether.c
1 /* MOXA ART Ethernet (RTL8201CP) driver.
2  *
3  * Copyright (C) 2013 Jonas Jensen
4  *
5  * Jonas Jensen <jonas.jensen@gmail.com>
6  *
7  * Based on code from
8  * Moxa Technology Co., Ltd. <www.moxa.com>
9  *
10  * This file is licensed under the terms of the GNU General Public
11  * License version 2.  This program is licensed "as is" without any
12  * warranty of any kind, whether express or implied.
13  */
14
15 #include <linux/module.h>
16 #include <linux/netdevice.h>
17 #include <linux/etherdevice.h>
18 #include <linux/skbuff.h>
19 #include <linux/dma-mapping.h>
20 #include <linux/ethtool.h>
21 #include <linux/platform_device.h>
22 #include <linux/interrupt.h>
23 #include <linux/irq.h>
24 #include <linux/of_address.h>
25 #include <linux/of_irq.h>
26 #include <linux/crc32.h>
27 #include <linux/crc32c.h>
28 #include <linux/circ_buf.h>
29
30 #include "moxart_ether.h"
31
32 static inline void moxart_desc_write(u32 data, u32 *desc)
33 {
34         *desc = cpu_to_le32(data);
35 }
36
37 static inline u32 moxart_desc_read(u32 *desc)
38 {
39         return le32_to_cpu(*desc);
40 }
41
42 static inline void moxart_emac_write(struct net_device *ndev,
43                                      unsigned int reg, unsigned long value)
44 {
45         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
46
47         writel(value, priv->base + reg);
48 }
49
50 static void moxart_update_mac_address(struct net_device *ndev)
51 {
52         moxart_emac_write(ndev, REG_MAC_MS_ADDRESS,
53                           ((ndev->dev_addr[0] << 8) | (ndev->dev_addr[1])));
54         moxart_emac_write(ndev, REG_MAC_MS_ADDRESS + 4,
55                           ((ndev->dev_addr[2] << 24) |
56                            (ndev->dev_addr[3] << 16) |
57                            (ndev->dev_addr[4] << 8) |
58                            (ndev->dev_addr[5])));
59 }
60
61 static int moxart_set_mac_address(struct net_device *ndev, void *addr)
62 {
63         struct sockaddr *address = addr;
64
65         if (!is_valid_ether_addr(address->sa_data))
66                 return -EADDRNOTAVAIL;
67
68         memcpy(ndev->dev_addr, address->sa_data, ndev->addr_len);
69         moxart_update_mac_address(ndev);
70
71         return 0;
72 }
73
74 static void moxart_mac_free_memory(struct net_device *ndev)
75 {
76         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
77         int i;
78
79         for (i = 0; i < RX_DESC_NUM; i++)
80                 dma_unmap_single(&ndev->dev, priv->rx_mapping[i],
81                                  priv->rx_buf_size, DMA_FROM_DEVICE);
82
83         if (priv->tx_desc_base)
84                 dma_free_coherent(NULL, TX_REG_DESC_SIZE * TX_DESC_NUM,
85                                   priv->tx_desc_base, priv->tx_base);
86
87         if (priv->rx_desc_base)
88                 dma_free_coherent(NULL, RX_REG_DESC_SIZE * RX_DESC_NUM,
89                                   priv->rx_desc_base, priv->rx_base);
90
91         kfree(priv->tx_buf_base);
92         kfree(priv->rx_buf_base);
93 }
94
95 static void moxart_mac_reset(struct net_device *ndev)
96 {
97         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
98
99         writel(SW_RST, priv->base + REG_MAC_CTRL);
100         while (readl(priv->base + REG_MAC_CTRL) & SW_RST)
101                 mdelay(10);
102
103         writel(0, priv->base + REG_INTERRUPT_MASK);
104
105         priv->reg_maccr = RX_BROADPKT | FULLDUP | CRC_APD | RX_FTL;
106 }
107
108 static void moxart_mac_enable(struct net_device *ndev)
109 {
110         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
111
112         writel(0x00001010, priv->base + REG_INT_TIMER_CTRL);
113         writel(0x00000001, priv->base + REG_APOLL_TIMER_CTRL);
114         writel(0x00000390, priv->base + REG_DMA_BLEN_CTRL);
115
116         priv->reg_imr |= (RPKT_FINISH_M | XPKT_FINISH_M);
117         writel(priv->reg_imr, priv->base + REG_INTERRUPT_MASK);
118
119         priv->reg_maccr |= (RCV_EN | XMT_EN | RDMA_EN | XDMA_EN);
120         writel(priv->reg_maccr, priv->base + REG_MAC_CTRL);
121 }
122
123 static void moxart_mac_setup_desc_ring(struct net_device *ndev)
124 {
125         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
126         void *desc;
127         int i;
128
129         for (i = 0; i < TX_DESC_NUM; i++) {
130                 desc = priv->tx_desc_base + i * TX_REG_DESC_SIZE;
131                 memset(desc, 0, TX_REG_DESC_SIZE);
132
133                 priv->tx_buf[i] = priv->tx_buf_base + priv->tx_buf_size * i;
134         }
135         moxart_desc_write(TX_DESC1_END, desc + TX_REG_OFFSET_DESC1);
136
137         priv->tx_head = 0;
138         priv->tx_tail = 0;
139
140         for (i = 0; i < RX_DESC_NUM; i++) {
141                 desc = priv->rx_desc_base + i * RX_REG_DESC_SIZE;
142                 memset(desc, 0, RX_REG_DESC_SIZE);
143                 moxart_desc_write(RX_DESC0_DMA_OWN, desc + RX_REG_OFFSET_DESC0);
144                 moxart_desc_write(RX_BUF_SIZE & RX_DESC1_BUF_SIZE_MASK,
145                        desc + RX_REG_OFFSET_DESC1);
146
147                 priv->rx_buf[i] = priv->rx_buf_base + priv->rx_buf_size * i;
148                 priv->rx_mapping[i] = dma_map_single(&ndev->dev,
149                                                      priv->rx_buf[i],
150                                                      priv->rx_buf_size,
151                                                      DMA_FROM_DEVICE);
152                 if (dma_mapping_error(&ndev->dev, priv->rx_mapping[i]))
153                         netdev_err(ndev, "DMA mapping error\n");
154
155                 moxart_desc_write(priv->rx_mapping[i],
156                        desc + RX_REG_OFFSET_DESC2 + RX_DESC2_ADDRESS_PHYS);
157                 moxart_desc_write((uintptr_t)priv->rx_buf[i],
158                        desc + RX_REG_OFFSET_DESC2 + RX_DESC2_ADDRESS_VIRT);
159         }
160         moxart_desc_write(RX_DESC1_END, desc + RX_REG_OFFSET_DESC1);
161
162         priv->rx_head = 0;
163
164         /* reset the MAC controller TX/RX descriptor base address */
165         writel(priv->tx_base, priv->base + REG_TXR_BASE_ADDRESS);
166         writel(priv->rx_base, priv->base + REG_RXR_BASE_ADDRESS);
167 }
168
169 static int moxart_mac_open(struct net_device *ndev)
170 {
171         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
172
173         if (!is_valid_ether_addr(ndev->dev_addr))
174                 return -EADDRNOTAVAIL;
175
176         napi_enable(&priv->napi);
177
178         moxart_mac_reset(ndev);
179         moxart_update_mac_address(ndev);
180         moxart_mac_setup_desc_ring(ndev);
181         moxart_mac_enable(ndev);
182         netif_start_queue(ndev);
183
184         netdev_dbg(ndev, "%s: IMR=0x%x, MACCR=0x%x\n",
185                    __func__, readl(priv->base + REG_INTERRUPT_MASK),
186                    readl(priv->base + REG_MAC_CTRL));
187
188         return 0;
189 }
190
191 static int moxart_mac_stop(struct net_device *ndev)
192 {
193         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
194
195         napi_disable(&priv->napi);
196
197         netif_stop_queue(ndev);
198
199         /* disable all interrupts */
200         writel(0, priv->base + REG_INTERRUPT_MASK);
201
202         /* disable all functions */
203         writel(0, priv->base + REG_MAC_CTRL);
204
205         return 0;
206 }
207
208 static int moxart_rx_poll(struct napi_struct *napi, int budget)
209 {
210         struct moxart_mac_priv_t *priv = container_of(napi,
211                                                       struct moxart_mac_priv_t,
212                                                       napi);
213         struct net_device *ndev = priv->ndev;
214         struct sk_buff *skb;
215         void *desc;
216         unsigned int desc0, len;
217         int rx_head = priv->rx_head;
218         int rx = 0;
219
220         while (rx < budget) {
221                 desc = priv->rx_desc_base + (RX_REG_DESC_SIZE * rx_head);
222                 desc0 = moxart_desc_read(desc + RX_REG_OFFSET_DESC0);
223                 rmb(); /* ensure desc0 is up to date */
224
225                 if (desc0 & RX_DESC0_DMA_OWN)
226                         break;
227
228                 if (desc0 & (RX_DESC0_ERR | RX_DESC0_CRC_ERR | RX_DESC0_FTL |
229                              RX_DESC0_RUNT | RX_DESC0_ODD_NB)) {
230                         net_dbg_ratelimited("packet error\n");
231                         ndev->stats.rx_dropped++;
232                         ndev->stats.rx_errors++;
233                         goto rx_next;
234                 }
235
236                 len = desc0 & RX_DESC0_FRAME_LEN_MASK;
237
238                 if (len > RX_BUF_SIZE)
239                         len = RX_BUF_SIZE;
240
241                 dma_sync_single_for_cpu(&ndev->dev,
242                                         priv->rx_mapping[rx_head],
243                                         priv->rx_buf_size, DMA_FROM_DEVICE);
244                 skb = netdev_alloc_skb_ip_align(ndev, len);
245
246                 if (unlikely(!skb)) {
247                         net_dbg_ratelimited("netdev_alloc_skb_ip_align failed\n");
248                         ndev->stats.rx_dropped++;
249                         ndev->stats.rx_errors++;
250                         goto rx_next;
251                 }
252
253                 memcpy(skb->data, priv->rx_buf[rx_head], len);
254                 skb_put(skb, len);
255                 skb->protocol = eth_type_trans(skb, ndev);
256                 napi_gro_receive(&priv->napi, skb);
257                 rx++;
258
259                 ndev->stats.rx_packets++;
260                 ndev->stats.rx_bytes += len;
261                 if (desc0 & RX_DESC0_MULTICAST)
262                         ndev->stats.multicast++;
263
264 rx_next:
265                 wmb(); /* prevent setting ownership back too early */
266                 moxart_desc_write(RX_DESC0_DMA_OWN, desc + RX_REG_OFFSET_DESC0);
267
268                 rx_head = RX_NEXT(rx_head);
269                 priv->rx_head = rx_head;
270         }
271
272         if (rx < budget)
273                 napi_complete_done(napi, rx);
274
275         priv->reg_imr |= RPKT_FINISH_M;
276         writel(priv->reg_imr, priv->base + REG_INTERRUPT_MASK);
277
278         return rx;
279 }
280
281 static int moxart_tx_queue_space(struct net_device *ndev)
282 {
283         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
284
285         return CIRC_SPACE(priv->tx_head, priv->tx_tail, TX_DESC_NUM);
286 }
287
288 static void moxart_tx_finished(struct net_device *ndev)
289 {
290         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
291         unsigned int tx_head = priv->tx_head;
292         unsigned int tx_tail = priv->tx_tail;
293
294         while (tx_tail != tx_head) {
295                 dma_unmap_single(&ndev->dev, priv->tx_mapping[tx_tail],
296                                  priv->tx_len[tx_tail], DMA_TO_DEVICE);
297
298                 ndev->stats.tx_packets++;
299                 ndev->stats.tx_bytes += priv->tx_skb[tx_tail]->len;
300
301                 dev_kfree_skb_irq(priv->tx_skb[tx_tail]);
302                 priv->tx_skb[tx_tail] = NULL;
303
304                 tx_tail = TX_NEXT(tx_tail);
305         }
306         priv->tx_tail = tx_tail;
307         if (netif_queue_stopped(ndev) &&
308             moxart_tx_queue_space(ndev) >= TX_WAKE_THRESHOLD)
309                 netif_wake_queue(ndev);
310 }
311
312 static irqreturn_t moxart_mac_interrupt(int irq, void *dev_id)
313 {
314         struct net_device *ndev = (struct net_device *)dev_id;
315         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
316         unsigned int ists = readl(priv->base + REG_INTERRUPT_STATUS);
317
318         if (ists & XPKT_OK_INT_STS)
319                 moxart_tx_finished(ndev);
320
321         if (ists & RPKT_FINISH) {
322                 if (napi_schedule_prep(&priv->napi)) {
323                         priv->reg_imr &= ~RPKT_FINISH_M;
324                         writel(priv->reg_imr, priv->base + REG_INTERRUPT_MASK);
325                         __napi_schedule(&priv->napi);
326                 }
327         }
328
329         return IRQ_HANDLED;
330 }
331
332 static int moxart_mac_start_xmit(struct sk_buff *skb, struct net_device *ndev)
333 {
334         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
335         void *desc;
336         unsigned int len;
337         unsigned int tx_head;
338         u32 txdes1;
339         int ret = NETDEV_TX_BUSY;
340
341         spin_lock_irq(&priv->txlock);
342
343         tx_head = priv->tx_head;
344         desc = priv->tx_desc_base + (TX_REG_DESC_SIZE * tx_head);
345
346         if (moxart_tx_queue_space(ndev) == 1)
347                 netif_stop_queue(ndev);
348
349         if (moxart_desc_read(desc + TX_REG_OFFSET_DESC0) & TX_DESC0_DMA_OWN) {
350                 net_dbg_ratelimited("no TX space for packet\n");
351                 ndev->stats.tx_dropped++;
352                 goto out_unlock;
353         }
354         rmb(); /* ensure data is only read that had TX_DESC0_DMA_OWN cleared */
355
356         len = skb->len > TX_BUF_SIZE ? TX_BUF_SIZE : skb->len;
357
358         priv->tx_mapping[tx_head] = dma_map_single(&ndev->dev, skb->data,
359                                                    len, DMA_TO_DEVICE);
360         if (dma_mapping_error(&ndev->dev, priv->tx_mapping[tx_head])) {
361                 netdev_err(ndev, "DMA mapping error\n");
362                 goto out_unlock;
363         }
364
365         priv->tx_len[tx_head] = len;
366         priv->tx_skb[tx_head] = skb;
367
368         moxart_desc_write(priv->tx_mapping[tx_head],
369                desc + TX_REG_OFFSET_DESC2 + TX_DESC2_ADDRESS_PHYS);
370         moxart_desc_write((uintptr_t)skb->data,
371                desc + TX_REG_OFFSET_DESC2 + TX_DESC2_ADDRESS_VIRT);
372
373         if (skb->len < ETH_ZLEN) {
374                 memset(&skb->data[skb->len],
375                        0, ETH_ZLEN - skb->len);
376                 len = ETH_ZLEN;
377         }
378
379         dma_sync_single_for_device(&ndev->dev, priv->tx_mapping[tx_head],
380                                    priv->tx_buf_size, DMA_TO_DEVICE);
381
382         txdes1 = TX_DESC1_LTS | TX_DESC1_FTS | (len & TX_DESC1_BUF_SIZE_MASK);
383         if (tx_head == TX_DESC_NUM_MASK)
384                 txdes1 |= TX_DESC1_END;
385         moxart_desc_write(txdes1, desc + TX_REG_OFFSET_DESC1);
386         wmb(); /* flush descriptor before transferring ownership */
387         moxart_desc_write(TX_DESC0_DMA_OWN, desc + TX_REG_OFFSET_DESC0);
388
389         /* start to send packet */
390         writel(0xffffffff, priv->base + REG_TX_POLL_DEMAND);
391
392         priv->tx_head = TX_NEXT(tx_head);
393
394         netif_trans_update(ndev);
395         ret = NETDEV_TX_OK;
396 out_unlock:
397         spin_unlock_irq(&priv->txlock);
398
399         return ret;
400 }
401
402 static void moxart_mac_setmulticast(struct net_device *ndev)
403 {
404         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
405         struct netdev_hw_addr *ha;
406         int crc_val;
407
408         netdev_for_each_mc_addr(ha, ndev) {
409                 crc_val = crc32_le(~0, ha->addr, ETH_ALEN);
410                 crc_val = (crc_val >> 26) & 0x3f;
411                 if (crc_val >= 32) {
412                         writel(readl(priv->base + REG_MCAST_HASH_TABLE1) |
413                                (1UL << (crc_val - 32)),
414                                priv->base + REG_MCAST_HASH_TABLE1);
415                 } else {
416                         writel(readl(priv->base + REG_MCAST_HASH_TABLE0) |
417                                (1UL << crc_val),
418                                priv->base + REG_MCAST_HASH_TABLE0);
419                 }
420         }
421 }
422
423 static void moxart_mac_set_rx_mode(struct net_device *ndev)
424 {
425         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
426
427         spin_lock_irq(&priv->txlock);
428
429         (ndev->flags & IFF_PROMISC) ? (priv->reg_maccr |= RCV_ALL) :
430                                       (priv->reg_maccr &= ~RCV_ALL);
431
432         (ndev->flags & IFF_ALLMULTI) ? (priv->reg_maccr |= RX_MULTIPKT) :
433                                        (priv->reg_maccr &= ~RX_MULTIPKT);
434
435         if ((ndev->flags & IFF_MULTICAST) && netdev_mc_count(ndev)) {
436                 priv->reg_maccr |= HT_MULTI_EN;
437                 moxart_mac_setmulticast(ndev);
438         } else {
439                 priv->reg_maccr &= ~HT_MULTI_EN;
440         }
441
442         writel(priv->reg_maccr, priv->base + REG_MAC_CTRL);
443
444         spin_unlock_irq(&priv->txlock);
445 }
446
447 static const struct net_device_ops moxart_netdev_ops = {
448         .ndo_open               = moxart_mac_open,
449         .ndo_stop               = moxart_mac_stop,
450         .ndo_start_xmit         = moxart_mac_start_xmit,
451         .ndo_set_rx_mode        = moxart_mac_set_rx_mode,
452         .ndo_set_mac_address    = moxart_set_mac_address,
453         .ndo_validate_addr      = eth_validate_addr,
454 };
455
456 static int moxart_mac_probe(struct platform_device *pdev)
457 {
458         struct device *p_dev = &pdev->dev;
459         struct device_node *node = p_dev->of_node;
460         struct net_device *ndev;
461         struct moxart_mac_priv_t *priv;
462         struct resource *res;
463         unsigned int irq;
464         int ret;
465
466         ndev = alloc_etherdev(sizeof(struct moxart_mac_priv_t));
467         if (!ndev)
468                 return -ENOMEM;
469
470         irq = irq_of_parse_and_map(node, 0);
471         if (irq <= 0) {
472                 netdev_err(ndev, "irq_of_parse_and_map failed\n");
473                 ret = -EINVAL;
474                 goto irq_map_fail;
475         }
476
477         priv = netdev_priv(ndev);
478         priv->ndev = ndev;
479
480         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
481         ndev->base_addr = res->start;
482         priv->base = devm_ioremap_resource(p_dev, res);
483         if (IS_ERR(priv->base)) {
484                 dev_err(p_dev, "devm_ioremap_resource failed\n");
485                 ret = PTR_ERR(priv->base);
486                 goto init_fail;
487         }
488
489         spin_lock_init(&priv->txlock);
490
491         priv->tx_buf_size = TX_BUF_SIZE;
492         priv->rx_buf_size = RX_BUF_SIZE;
493
494         priv->tx_desc_base = dma_alloc_coherent(NULL, TX_REG_DESC_SIZE *
495                                                 TX_DESC_NUM, &priv->tx_base,
496                                                 GFP_DMA | GFP_KERNEL);
497         if (!priv->tx_desc_base) {
498                 ret = -ENOMEM;
499                 goto init_fail;
500         }
501
502         priv->rx_desc_base = dma_alloc_coherent(NULL, RX_REG_DESC_SIZE *
503                                                 RX_DESC_NUM, &priv->rx_base,
504                                                 GFP_DMA | GFP_KERNEL);
505         if (!priv->rx_desc_base) {
506                 ret = -ENOMEM;
507                 goto init_fail;
508         }
509
510         priv->tx_buf_base = kmalloc_array(priv->tx_buf_size, TX_DESC_NUM,
511                                           GFP_ATOMIC);
512         if (!priv->tx_buf_base) {
513                 ret = -ENOMEM;
514                 goto init_fail;
515         }
516
517         priv->rx_buf_base = kmalloc_array(priv->rx_buf_size, RX_DESC_NUM,
518                                           GFP_ATOMIC);
519         if (!priv->rx_buf_base) {
520                 ret = -ENOMEM;
521                 goto init_fail;
522         }
523
524         platform_set_drvdata(pdev, ndev);
525
526         ret = devm_request_irq(p_dev, irq, moxart_mac_interrupt, 0,
527                                pdev->name, ndev);
528         if (ret) {
529                 netdev_err(ndev, "devm_request_irq failed\n");
530                 goto init_fail;
531         }
532
533         ndev->netdev_ops = &moxart_netdev_ops;
534         netif_napi_add(ndev, &priv->napi, moxart_rx_poll, RX_DESC_NUM);
535         ndev->priv_flags |= IFF_UNICAST_FLT;
536         ndev->irq = irq;
537
538         SET_NETDEV_DEV(ndev, &pdev->dev);
539
540         ret = register_netdev(ndev);
541         if (ret)
542                 goto init_fail;
543
544         netdev_dbg(ndev, "%s: IRQ=%d address=%pM\n",
545                    __func__, ndev->irq, ndev->dev_addr);
546
547         return 0;
548
549 init_fail:
550         netdev_err(ndev, "init failed\n");
551         moxart_mac_free_memory(ndev);
552 irq_map_fail:
553         free_netdev(ndev);
554         return ret;
555 }
556
557 static int moxart_remove(struct platform_device *pdev)
558 {
559         struct net_device *ndev = platform_get_drvdata(pdev);
560
561         unregister_netdev(ndev);
562         devm_free_irq(&pdev->dev, ndev->irq, ndev);
563         moxart_mac_free_memory(ndev);
564         free_netdev(ndev);
565
566         return 0;
567 }
568
569 static const struct of_device_id moxart_mac_match[] = {
570         { .compatible = "moxa,moxart-mac" },
571         { }
572 };
573 MODULE_DEVICE_TABLE(of, moxart_mac_match);
574
575 static struct platform_driver moxart_mac_driver = {
576         .probe  = moxart_mac_probe,
577         .remove = moxart_remove,
578         .driver = {
579                 .name           = "moxart-ethernet",
580                 .of_match_table = moxart_mac_match,
581         },
582 };
583 module_platform_driver(moxart_mac_driver);
584
585 MODULE_DESCRIPTION("MOXART RTL8201CP Ethernet driver");
586 MODULE_LICENSE("GPL v2");
587 MODULE_AUTHOR("Jonas Jensen <jonas.jensen@gmail.com>");