GNU Linux-libre 6.8.7-gnu
[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, __le32 *desc)
33 {
34         *desc = cpu_to_le32(data);
35 }
36
37 static inline u32 moxart_desc_read(__le32 *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         eth_hw_addr_set(ndev, address->sa_data);
66         moxart_update_mac_address(ndev);
67
68         return 0;
69 }
70
71 static void moxart_mac_free_memory(struct net_device *ndev)
72 {
73         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
74
75         if (priv->tx_desc_base)
76                 dma_free_coherent(&priv->pdev->dev,
77                                   TX_REG_DESC_SIZE * TX_DESC_NUM,
78                                   priv->tx_desc_base, priv->tx_base);
79
80         if (priv->rx_desc_base)
81                 dma_free_coherent(&priv->pdev->dev,
82                                   RX_REG_DESC_SIZE * RX_DESC_NUM,
83                                   priv->rx_desc_base, priv->rx_base);
84
85         kfree(priv->tx_buf_base);
86         kfree(priv->rx_buf_base);
87 }
88
89 static void moxart_mac_reset(struct net_device *ndev)
90 {
91         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
92
93         writel(SW_RST, priv->base + REG_MAC_CTRL);
94         while (readl(priv->base + REG_MAC_CTRL) & SW_RST)
95                 mdelay(10);
96
97         writel(0, priv->base + REG_INTERRUPT_MASK);
98
99         priv->reg_maccr = RX_BROADPKT | FULLDUP | CRC_APD | RX_FTL;
100 }
101
102 static void moxart_mac_enable(struct net_device *ndev)
103 {
104         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
105
106         writel(0x00001010, priv->base + REG_INT_TIMER_CTRL);
107         writel(0x00000001, priv->base + REG_APOLL_TIMER_CTRL);
108         writel(0x00000390, priv->base + REG_DMA_BLEN_CTRL);
109
110         priv->reg_imr |= (RPKT_FINISH_M | XPKT_FINISH_M);
111         writel(priv->reg_imr, priv->base + REG_INTERRUPT_MASK);
112
113         priv->reg_maccr |= (RCV_EN | XMT_EN | RDMA_EN | XDMA_EN);
114         writel(priv->reg_maccr, priv->base + REG_MAC_CTRL);
115 }
116
117 static void moxart_mac_setup_desc_ring(struct net_device *ndev)
118 {
119         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
120         void *desc;
121         int i;
122
123         for (i = 0; i < TX_DESC_NUM; i++) {
124                 desc = priv->tx_desc_base + i * TX_REG_DESC_SIZE;
125                 memset(desc, 0, TX_REG_DESC_SIZE);
126
127                 priv->tx_buf[i] = priv->tx_buf_base + priv->tx_buf_size * i;
128         }
129         moxart_desc_write(TX_DESC1_END, desc + TX_REG_OFFSET_DESC1);
130
131         priv->tx_head = 0;
132         priv->tx_tail = 0;
133
134         for (i = 0; i < RX_DESC_NUM; i++) {
135                 desc = priv->rx_desc_base + i * RX_REG_DESC_SIZE;
136                 memset(desc, 0, RX_REG_DESC_SIZE);
137                 moxart_desc_write(RX_DESC0_DMA_OWN, desc + RX_REG_OFFSET_DESC0);
138                 moxart_desc_write(RX_BUF_SIZE & RX_DESC1_BUF_SIZE_MASK,
139                        desc + RX_REG_OFFSET_DESC1);
140
141                 priv->rx_buf[i] = priv->rx_buf_base + priv->rx_buf_size * i;
142                 priv->rx_mapping[i] = dma_map_single(&priv->pdev->dev,
143                                                      priv->rx_buf[i],
144                                                      priv->rx_buf_size,
145                                                      DMA_FROM_DEVICE);
146                 if (dma_mapping_error(&priv->pdev->dev, priv->rx_mapping[i]))
147                         netdev_err(ndev, "DMA mapping error\n");
148
149                 moxart_desc_write(priv->rx_mapping[i],
150                        desc + RX_REG_OFFSET_DESC2 + RX_DESC2_ADDRESS_PHYS);
151                 moxart_desc_write((uintptr_t)priv->rx_buf[i],
152                        desc + RX_REG_OFFSET_DESC2 + RX_DESC2_ADDRESS_VIRT);
153         }
154         moxart_desc_write(RX_DESC1_END, desc + RX_REG_OFFSET_DESC1);
155
156         priv->rx_head = 0;
157
158         /* reset the MAC controller TX/RX descriptor base address */
159         writel(priv->tx_base, priv->base + REG_TXR_BASE_ADDRESS);
160         writel(priv->rx_base, priv->base + REG_RXR_BASE_ADDRESS);
161 }
162
163 static int moxart_mac_open(struct net_device *ndev)
164 {
165         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
166
167         napi_enable(&priv->napi);
168
169         moxart_mac_reset(ndev);
170         moxart_update_mac_address(ndev);
171         moxart_mac_setup_desc_ring(ndev);
172         moxart_mac_enable(ndev);
173         netif_start_queue(ndev);
174
175         netdev_dbg(ndev, "%s: IMR=0x%x, MACCR=0x%x\n",
176                    __func__, readl(priv->base + REG_INTERRUPT_MASK),
177                    readl(priv->base + REG_MAC_CTRL));
178
179         return 0;
180 }
181
182 static int moxart_mac_stop(struct net_device *ndev)
183 {
184         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
185         int i;
186
187         napi_disable(&priv->napi);
188
189         netif_stop_queue(ndev);
190
191         /* disable all interrupts */
192         writel(0, priv->base + REG_INTERRUPT_MASK);
193
194         /* disable all functions */
195         writel(0, priv->base + REG_MAC_CTRL);
196
197         /* unmap areas mapped in moxart_mac_setup_desc_ring() */
198         for (i = 0; i < RX_DESC_NUM; i++)
199                 dma_unmap_single(&priv->pdev->dev, priv->rx_mapping[i],
200                                  priv->rx_buf_size, DMA_FROM_DEVICE);
201
202         return 0;
203 }
204
205 static int moxart_rx_poll(struct napi_struct *napi, int budget)
206 {
207         struct moxart_mac_priv_t *priv = container_of(napi,
208                                                       struct moxart_mac_priv_t,
209                                                       napi);
210         struct net_device *ndev = priv->ndev;
211         struct sk_buff *skb;
212         void *desc;
213         unsigned int desc0, len;
214         int rx_head = priv->rx_head;
215         int rx = 0;
216
217         while (rx < budget) {
218                 desc = priv->rx_desc_base + (RX_REG_DESC_SIZE * rx_head);
219                 desc0 = moxart_desc_read(desc + RX_REG_OFFSET_DESC0);
220                 rmb(); /* ensure desc0 is up to date */
221
222                 if (desc0 & RX_DESC0_DMA_OWN)
223                         break;
224
225                 if (desc0 & (RX_DESC0_ERR | RX_DESC0_CRC_ERR | RX_DESC0_FTL |
226                              RX_DESC0_RUNT | RX_DESC0_ODD_NB)) {
227                         net_dbg_ratelimited("packet error\n");
228                         ndev->stats.rx_dropped++;
229                         ndev->stats.rx_errors++;
230                         goto rx_next;
231                 }
232
233                 len = desc0 & RX_DESC0_FRAME_LEN_MASK;
234
235                 if (len > RX_BUF_SIZE)
236                         len = RX_BUF_SIZE;
237
238                 dma_sync_single_for_cpu(&priv->pdev->dev,
239                                         priv->rx_mapping[rx_head],
240                                         priv->rx_buf_size, DMA_FROM_DEVICE);
241                 skb = netdev_alloc_skb_ip_align(ndev, len);
242
243                 if (unlikely(!skb)) {
244                         net_dbg_ratelimited("netdev_alloc_skb_ip_align failed\n");
245                         ndev->stats.rx_dropped++;
246                         ndev->stats.rx_errors++;
247                         goto rx_next;
248                 }
249
250                 memcpy(skb->data, priv->rx_buf[rx_head], len);
251                 skb_put(skb, len);
252                 skb->protocol = eth_type_trans(skb, ndev);
253                 napi_gro_receive(&priv->napi, skb);
254                 rx++;
255
256                 ndev->stats.rx_packets++;
257                 ndev->stats.rx_bytes += len;
258                 if (desc0 & RX_DESC0_MULTICAST)
259                         ndev->stats.multicast++;
260
261 rx_next:
262                 wmb(); /* prevent setting ownership back too early */
263                 moxart_desc_write(RX_DESC0_DMA_OWN, desc + RX_REG_OFFSET_DESC0);
264
265                 rx_head = RX_NEXT(rx_head);
266                 priv->rx_head = rx_head;
267         }
268
269         if (rx < budget)
270                 napi_complete_done(napi, rx);
271
272         priv->reg_imr |= RPKT_FINISH_M;
273         writel(priv->reg_imr, priv->base + REG_INTERRUPT_MASK);
274
275         return rx;
276 }
277
278 static int moxart_tx_queue_space(struct net_device *ndev)
279 {
280         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
281
282         return CIRC_SPACE(priv->tx_head, priv->tx_tail, TX_DESC_NUM);
283 }
284
285 static void moxart_tx_finished(struct net_device *ndev)
286 {
287         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
288         unsigned int tx_head = priv->tx_head;
289         unsigned int tx_tail = priv->tx_tail;
290
291         while (tx_tail != tx_head) {
292                 dma_unmap_single(&priv->pdev->dev, priv->tx_mapping[tx_tail],
293                                  priv->tx_len[tx_tail], DMA_TO_DEVICE);
294
295                 ndev->stats.tx_packets++;
296                 ndev->stats.tx_bytes += priv->tx_skb[tx_tail]->len;
297
298                 dev_consume_skb_irq(priv->tx_skb[tx_tail]);
299                 priv->tx_skb[tx_tail] = NULL;
300
301                 tx_tail = TX_NEXT(tx_tail);
302         }
303         priv->tx_tail = tx_tail;
304         if (netif_queue_stopped(ndev) &&
305             moxart_tx_queue_space(ndev) >= TX_WAKE_THRESHOLD)
306                 netif_wake_queue(ndev);
307 }
308
309 static irqreturn_t moxart_mac_interrupt(int irq, void *dev_id)
310 {
311         struct net_device *ndev = (struct net_device *)dev_id;
312         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
313         unsigned int ists = readl(priv->base + REG_INTERRUPT_STATUS);
314
315         if (ists & XPKT_OK_INT_STS)
316                 moxart_tx_finished(ndev);
317
318         if (ists & RPKT_FINISH) {
319                 if (napi_schedule_prep(&priv->napi)) {
320                         priv->reg_imr &= ~RPKT_FINISH_M;
321                         writel(priv->reg_imr, priv->base + REG_INTERRUPT_MASK);
322                         __napi_schedule(&priv->napi);
323                 }
324         }
325
326         return IRQ_HANDLED;
327 }
328
329 static netdev_tx_t moxart_mac_start_xmit(struct sk_buff *skb,
330                                          struct net_device *ndev)
331 {
332         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
333         void *desc;
334         unsigned int len;
335         unsigned int tx_head;
336         u32 txdes1;
337         netdev_tx_t ret = NETDEV_TX_BUSY;
338
339         spin_lock_irq(&priv->txlock);
340
341         tx_head = priv->tx_head;
342         desc = priv->tx_desc_base + (TX_REG_DESC_SIZE * tx_head);
343
344         if (moxart_tx_queue_space(ndev) == 1)
345                 netif_stop_queue(ndev);
346
347         if (moxart_desc_read(desc + TX_REG_OFFSET_DESC0) & TX_DESC0_DMA_OWN) {
348                 net_dbg_ratelimited("no TX space for packet\n");
349                 ndev->stats.tx_dropped++;
350                 goto out_unlock;
351         }
352         rmb(); /* ensure data is only read that had TX_DESC0_DMA_OWN cleared */
353
354         len = skb->len > TX_BUF_SIZE ? TX_BUF_SIZE : skb->len;
355
356         priv->tx_mapping[tx_head] = dma_map_single(&priv->pdev->dev, skb->data,
357                                                    len, DMA_TO_DEVICE);
358         if (dma_mapping_error(&priv->pdev->dev, priv->tx_mapping[tx_head])) {
359                 netdev_err(ndev, "DMA mapping error\n");
360                 goto out_unlock;
361         }
362
363         priv->tx_len[tx_head] = len;
364         priv->tx_skb[tx_head] = skb;
365
366         moxart_desc_write(priv->tx_mapping[tx_head],
367                desc + TX_REG_OFFSET_DESC2 + TX_DESC2_ADDRESS_PHYS);
368         moxart_desc_write((uintptr_t)skb->data,
369                desc + TX_REG_OFFSET_DESC2 + TX_DESC2_ADDRESS_VIRT);
370
371         if (skb->len < ETH_ZLEN) {
372                 memset(&skb->data[skb->len],
373                        0, ETH_ZLEN - skb->len);
374                 len = ETH_ZLEN;
375         }
376
377         dma_sync_single_for_device(&priv->pdev->dev, priv->tx_mapping[tx_head],
378                                    priv->tx_buf_size, DMA_TO_DEVICE);
379
380         txdes1 = TX_DESC1_LTS | TX_DESC1_FTS | (len & TX_DESC1_BUF_SIZE_MASK);
381         if (tx_head == TX_DESC_NUM_MASK)
382                 txdes1 |= TX_DESC1_END;
383         moxart_desc_write(txdes1, desc + TX_REG_OFFSET_DESC1);
384         wmb(); /* flush descriptor before transferring ownership */
385         moxart_desc_write(TX_DESC0_DMA_OWN, desc + TX_REG_OFFSET_DESC0);
386
387         /* start to send packet */
388         writel(0xffffffff, priv->base + REG_TX_POLL_DEMAND);
389
390         priv->tx_head = TX_NEXT(tx_head);
391
392         netif_trans_update(ndev);
393         ret = NETDEV_TX_OK;
394 out_unlock:
395         spin_unlock_irq(&priv->txlock);
396
397         return ret;
398 }
399
400 static void moxart_mac_setmulticast(struct net_device *ndev)
401 {
402         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
403         struct netdev_hw_addr *ha;
404         int crc_val;
405
406         netdev_for_each_mc_addr(ha, ndev) {
407                 crc_val = crc32_le(~0, ha->addr, ETH_ALEN);
408                 crc_val = (crc_val >> 26) & 0x3f;
409                 if (crc_val >= 32) {
410                         writel(readl(priv->base + REG_MCAST_HASH_TABLE1) |
411                                (1UL << (crc_val - 32)),
412                                priv->base + REG_MCAST_HASH_TABLE1);
413                 } else {
414                         writel(readl(priv->base + REG_MCAST_HASH_TABLE0) |
415                                (1UL << crc_val),
416                                priv->base + REG_MCAST_HASH_TABLE0);
417                 }
418         }
419 }
420
421 static void moxart_mac_set_rx_mode(struct net_device *ndev)
422 {
423         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
424
425         spin_lock_irq(&priv->txlock);
426
427         (ndev->flags & IFF_PROMISC) ? (priv->reg_maccr |= RCV_ALL) :
428                                       (priv->reg_maccr &= ~RCV_ALL);
429
430         (ndev->flags & IFF_ALLMULTI) ? (priv->reg_maccr |= RX_MULTIPKT) :
431                                        (priv->reg_maccr &= ~RX_MULTIPKT);
432
433         if ((ndev->flags & IFF_MULTICAST) && netdev_mc_count(ndev)) {
434                 priv->reg_maccr |= HT_MULTI_EN;
435                 moxart_mac_setmulticast(ndev);
436         } else {
437                 priv->reg_maccr &= ~HT_MULTI_EN;
438         }
439
440         writel(priv->reg_maccr, priv->base + REG_MAC_CTRL);
441
442         spin_unlock_irq(&priv->txlock);
443 }
444
445 static const struct net_device_ops moxart_netdev_ops = {
446         .ndo_open               = moxart_mac_open,
447         .ndo_stop               = moxart_mac_stop,
448         .ndo_start_xmit         = moxart_mac_start_xmit,
449         .ndo_set_rx_mode        = moxart_mac_set_rx_mode,
450         .ndo_set_mac_address    = moxart_set_mac_address,
451         .ndo_validate_addr      = eth_validate_addr,
452 };
453
454 static int moxart_mac_probe(struct platform_device *pdev)
455 {
456         struct device *p_dev = &pdev->dev;
457         struct device_node *node = p_dev->of_node;
458         struct net_device *ndev;
459         struct moxart_mac_priv_t *priv;
460         struct resource *res;
461         unsigned int irq;
462         int ret;
463
464         ndev = alloc_etherdev(sizeof(struct moxart_mac_priv_t));
465         if (!ndev)
466                 return -ENOMEM;
467
468         irq = irq_of_parse_and_map(node, 0);
469         if (irq <= 0) {
470                 netdev_err(ndev, "irq_of_parse_and_map failed\n");
471                 ret = -EINVAL;
472                 goto irq_map_fail;
473         }
474
475         priv = netdev_priv(ndev);
476         priv->ndev = ndev;
477         priv->pdev = pdev;
478
479         priv->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
480         if (IS_ERR(priv->base)) {
481                 ret = PTR_ERR(priv->base);
482                 goto init_fail;
483         }
484         ndev->base_addr = res->start;
485
486         ret = platform_get_ethdev_address(p_dev, ndev);
487         if (ret == -EPROBE_DEFER)
488                 goto init_fail;
489         if (ret)
490                 eth_hw_addr_random(ndev);
491         moxart_update_mac_address(ndev);
492
493         spin_lock_init(&priv->txlock);
494
495         priv->tx_buf_size = TX_BUF_SIZE;
496         priv->rx_buf_size = RX_BUF_SIZE;
497
498         priv->tx_desc_base = dma_alloc_coherent(p_dev, TX_REG_DESC_SIZE *
499                                                 TX_DESC_NUM, &priv->tx_base,
500                                                 GFP_DMA | GFP_KERNEL);
501         if (!priv->tx_desc_base) {
502                 ret = -ENOMEM;
503                 goto init_fail;
504         }
505
506         priv->rx_desc_base = dma_alloc_coherent(p_dev, RX_REG_DESC_SIZE *
507                                                 RX_DESC_NUM, &priv->rx_base,
508                                                 GFP_DMA | GFP_KERNEL);
509         if (!priv->rx_desc_base) {
510                 ret = -ENOMEM;
511                 goto init_fail;
512         }
513
514         priv->tx_buf_base = kmalloc_array(priv->tx_buf_size, TX_DESC_NUM,
515                                           GFP_KERNEL);
516         if (!priv->tx_buf_base) {
517                 ret = -ENOMEM;
518                 goto init_fail;
519         }
520
521         priv->rx_buf_base = kmalloc_array(priv->rx_buf_size, RX_DESC_NUM,
522                                           GFP_KERNEL);
523         if (!priv->rx_buf_base) {
524                 ret = -ENOMEM;
525                 goto init_fail;
526         }
527
528         platform_set_drvdata(pdev, ndev);
529
530         ret = devm_request_irq(p_dev, irq, moxart_mac_interrupt, 0,
531                                pdev->name, ndev);
532         if (ret) {
533                 netdev_err(ndev, "devm_request_irq failed\n");
534                 goto init_fail;
535         }
536
537         ndev->netdev_ops = &moxart_netdev_ops;
538         netif_napi_add_weight(ndev, &priv->napi, moxart_rx_poll, RX_DESC_NUM);
539         ndev->priv_flags |= IFF_UNICAST_FLT;
540         ndev->irq = irq;
541
542         SET_NETDEV_DEV(ndev, &pdev->dev);
543
544         ret = register_netdev(ndev);
545         if (ret)
546                 goto init_fail;
547
548         netdev_dbg(ndev, "%s: IRQ=%d address=%pM\n",
549                    __func__, ndev->irq, ndev->dev_addr);
550
551         return 0;
552
553 init_fail:
554         netdev_err(ndev, "init failed\n");
555         moxart_mac_free_memory(ndev);
556 irq_map_fail:
557         free_netdev(ndev);
558         return ret;
559 }
560
561 static void moxart_remove(struct platform_device *pdev)
562 {
563         struct net_device *ndev = platform_get_drvdata(pdev);
564
565         unregister_netdev(ndev);
566         devm_free_irq(&pdev->dev, ndev->irq, ndev);
567         moxart_mac_free_memory(ndev);
568         free_netdev(ndev);
569 }
570
571 static const struct of_device_id moxart_mac_match[] = {
572         { .compatible = "moxa,moxart-mac" },
573         { }
574 };
575 MODULE_DEVICE_TABLE(of, moxart_mac_match);
576
577 static struct platform_driver moxart_mac_driver = {
578         .probe  = moxart_mac_probe,
579         .remove_new = moxart_remove,
580         .driver = {
581                 .name           = "moxart-ethernet",
582                 .of_match_table = moxart_mac_match,
583         },
584 };
585 module_platform_driver(moxart_mac_driver);
586
587 MODULE_DESCRIPTION("MOXART RTL8201CP Ethernet driver");
588 MODULE_LICENSE("GPL v2");
589 MODULE_AUTHOR("Jonas Jensen <jonas.jensen@gmail.com>");