Merge tag 'vexpress-for-v4.6/dt-updates-2' of git://git.kernel.org/pub/scm/linux...
[cascardo/linux.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
29 #include "moxart_ether.h"
30
31 static inline void moxart_desc_write(u32 data, u32 *desc)
32 {
33         *desc = cpu_to_le32(data);
34 }
35
36 static inline u32 moxart_desc_read(u32 *desc)
37 {
38         return le32_to_cpu(*desc);
39 }
40
41 static inline void moxart_emac_write(struct net_device *ndev,
42                                      unsigned int reg, unsigned long value)
43 {
44         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
45
46         writel(value, priv->base + reg);
47 }
48
49 static void moxart_update_mac_address(struct net_device *ndev)
50 {
51         moxart_emac_write(ndev, REG_MAC_MS_ADDRESS,
52                           ((ndev->dev_addr[0] << 8) | (ndev->dev_addr[1])));
53         moxart_emac_write(ndev, REG_MAC_MS_ADDRESS + 4,
54                           ((ndev->dev_addr[2] << 24) |
55                            (ndev->dev_addr[3] << 16) |
56                            (ndev->dev_addr[4] << 8) |
57                            (ndev->dev_addr[5])));
58 }
59
60 static int moxart_set_mac_address(struct net_device *ndev, void *addr)
61 {
62         struct sockaddr *address = addr;
63
64         if (!is_valid_ether_addr(address->sa_data))
65                 return -EADDRNOTAVAIL;
66
67         memcpy(ndev->dev_addr, address->sa_data, ndev->addr_len);
68         moxart_update_mac_address(ndev);
69
70         return 0;
71 }
72
73 static void moxart_mac_free_memory(struct net_device *ndev)
74 {
75         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
76         int i;
77
78         for (i = 0; i < RX_DESC_NUM; i++)
79                 dma_unmap_single(&ndev->dev, priv->rx_mapping[i],
80                                  priv->rx_buf_size, DMA_FROM_DEVICE);
81
82         if (priv->tx_desc_base)
83                 dma_free_coherent(NULL, TX_REG_DESC_SIZE * TX_DESC_NUM,
84                                   priv->tx_desc_base, priv->tx_base);
85
86         if (priv->rx_desc_base)
87                 dma_free_coherent(NULL, RX_REG_DESC_SIZE * RX_DESC_NUM,
88                                   priv->rx_desc_base, priv->rx_base);
89
90         kfree(priv->tx_buf_base);
91         kfree(priv->rx_buf_base);
92 }
93
94 static void moxart_mac_reset(struct net_device *ndev)
95 {
96         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
97
98         writel(SW_RST, priv->base + REG_MAC_CTRL);
99         while (readl(priv->base + REG_MAC_CTRL) & SW_RST)
100                 mdelay(10);
101
102         writel(0, priv->base + REG_INTERRUPT_MASK);
103
104         priv->reg_maccr = RX_BROADPKT | FULLDUP | CRC_APD | RX_FTL;
105 }
106
107 static void moxart_mac_enable(struct net_device *ndev)
108 {
109         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
110
111         writel(0x00001010, priv->base + REG_INT_TIMER_CTRL);
112         writel(0x00000001, priv->base + REG_APOLL_TIMER_CTRL);
113         writel(0x00000390, priv->base + REG_DMA_BLEN_CTRL);
114
115         priv->reg_imr |= (RPKT_FINISH_M | XPKT_FINISH_M);
116         writel(priv->reg_imr, priv->base + REG_INTERRUPT_MASK);
117
118         priv->reg_maccr |= (RCV_EN | XMT_EN | RDMA_EN | XDMA_EN);
119         writel(priv->reg_maccr, priv->base + REG_MAC_CTRL);
120 }
121
122 static void moxart_mac_setup_desc_ring(struct net_device *ndev)
123 {
124         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
125         void *desc;
126         int i;
127
128         for (i = 0; i < TX_DESC_NUM; i++) {
129                 desc = priv->tx_desc_base + i * TX_REG_DESC_SIZE;
130                 memset(desc, 0, TX_REG_DESC_SIZE);
131
132                 priv->tx_buf[i] = priv->tx_buf_base + priv->tx_buf_size * i;
133         }
134         moxart_desc_write(TX_DESC1_END, desc + TX_REG_OFFSET_DESC1);
135
136         priv->tx_head = 0;
137         priv->tx_tail = 0;
138
139         for (i = 0; i < RX_DESC_NUM; i++) {
140                 desc = priv->rx_desc_base + i * RX_REG_DESC_SIZE;
141                 memset(desc, 0, RX_REG_DESC_SIZE);
142                 moxart_desc_write(RX_DESC0_DMA_OWN, desc + RX_REG_OFFSET_DESC0);
143                 moxart_desc_write(RX_BUF_SIZE & RX_DESC1_BUF_SIZE_MASK,
144                        desc + RX_REG_OFFSET_DESC1);
145
146                 priv->rx_buf[i] = priv->rx_buf_base + priv->rx_buf_size * i;
147                 priv->rx_mapping[i] = dma_map_single(&ndev->dev,
148                                                      priv->rx_buf[i],
149                                                      priv->rx_buf_size,
150                                                      DMA_FROM_DEVICE);
151                 if (dma_mapping_error(&ndev->dev, priv->rx_mapping[i]))
152                         netdev_err(ndev, "DMA mapping error\n");
153
154                 moxart_desc_write(priv->rx_mapping[i],
155                        desc + RX_REG_OFFSET_DESC2 + RX_DESC2_ADDRESS_PHYS);
156                 moxart_desc_write((uintptr_t)priv->rx_buf[i],
157                        desc + RX_REG_OFFSET_DESC2 + RX_DESC2_ADDRESS_VIRT);
158         }
159         moxart_desc_write(RX_DESC1_END, desc + RX_REG_OFFSET_DESC1);
160
161         priv->rx_head = 0;
162
163         /* reset the MAC controller TX/RX desciptor base address */
164         writel(priv->tx_base, priv->base + REG_TXR_BASE_ADDRESS);
165         writel(priv->rx_base, priv->base + REG_RXR_BASE_ADDRESS);
166 }
167
168 static int moxart_mac_open(struct net_device *ndev)
169 {
170         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
171
172         if (!is_valid_ether_addr(ndev->dev_addr))
173                 return -EADDRNOTAVAIL;
174
175         napi_enable(&priv->napi);
176
177         moxart_mac_reset(ndev);
178         moxart_update_mac_address(ndev);
179         moxart_mac_setup_desc_ring(ndev);
180         moxart_mac_enable(ndev);
181         netif_start_queue(ndev);
182
183         netdev_dbg(ndev, "%s: IMR=0x%x, MACCR=0x%x\n",
184                    __func__, readl(priv->base + REG_INTERRUPT_MASK),
185                    readl(priv->base + REG_MAC_CTRL));
186
187         return 0;
188 }
189
190 static int moxart_mac_stop(struct net_device *ndev)
191 {
192         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
193
194         napi_disable(&priv->napi);
195
196         netif_stop_queue(ndev);
197
198         /* disable all interrupts */
199         writel(0, priv->base + REG_INTERRUPT_MASK);
200
201         /* disable all functions */
202         writel(0, priv->base + REG_MAC_CTRL);
203
204         return 0;
205 }
206
207 static int moxart_rx_poll(struct napi_struct *napi, int budget)
208 {
209         struct moxart_mac_priv_t *priv = container_of(napi,
210                                                       struct moxart_mac_priv_t,
211                                                       napi);
212         struct net_device *ndev = priv->ndev;
213         struct sk_buff *skb;
214         void *desc;
215         unsigned int desc0, len;
216         int rx_head = priv->rx_head;
217         int rx = 0;
218
219         while (rx < budget) {
220                 desc = priv->rx_desc_base + (RX_REG_DESC_SIZE * rx_head);
221                 desc0 = moxart_desc_read(desc + RX_REG_OFFSET_DESC0);
222                 rmb(); /* ensure desc0 is up to date */
223
224                 if (desc0 & RX_DESC0_DMA_OWN)
225                         break;
226
227                 if (desc0 & (RX_DESC0_ERR | RX_DESC0_CRC_ERR | RX_DESC0_FTL |
228                              RX_DESC0_RUNT | RX_DESC0_ODD_NB)) {
229                         net_dbg_ratelimited("packet error\n");
230                         priv->stats.rx_dropped++;
231                         priv->stats.rx_errors++;
232                         goto rx_next;
233                 }
234
235                 len = desc0 & RX_DESC0_FRAME_LEN_MASK;
236
237                 if (len > RX_BUF_SIZE)
238                         len = RX_BUF_SIZE;
239
240                 dma_sync_single_for_cpu(&ndev->dev,
241                                         priv->rx_mapping[rx_head],
242                                         priv->rx_buf_size, DMA_FROM_DEVICE);
243                 skb = netdev_alloc_skb_ip_align(ndev, len);
244
245                 if (unlikely(!skb)) {
246                         net_dbg_ratelimited("netdev_alloc_skb_ip_align failed\n");
247                         priv->stats.rx_dropped++;
248                         priv->stats.rx_errors++;
249                         goto rx_next;
250                 }
251
252                 memcpy(skb->data, priv->rx_buf[rx_head], len);
253                 skb_put(skb, len);
254                 skb->protocol = eth_type_trans(skb, ndev);
255                 napi_gro_receive(&priv->napi, skb);
256                 rx++;
257
258                 priv->stats.rx_packets++;
259                 priv->stats.rx_bytes += len;
260                 if (desc0 & RX_DESC0_MULTICAST)
261                         priv->stats.multicast++;
262
263 rx_next:
264                 wmb(); /* prevent setting ownership back too early */
265                 moxart_desc_write(RX_DESC0_DMA_OWN, desc + RX_REG_OFFSET_DESC0);
266
267                 rx_head = RX_NEXT(rx_head);
268                 priv->rx_head = rx_head;
269         }
270
271         if (rx < budget) {
272                 napi_complete(napi);
273         }
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 void moxart_tx_finished(struct net_device *ndev)
282 {
283         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
284         unsigned tx_head = priv->tx_head;
285         unsigned tx_tail = priv->tx_tail;
286
287         while (tx_tail != tx_head) {
288                 dma_unmap_single(&ndev->dev, priv->tx_mapping[tx_tail],
289                                  priv->tx_len[tx_tail], DMA_TO_DEVICE);
290
291                 priv->stats.tx_packets++;
292                 priv->stats.tx_bytes += priv->tx_skb[tx_tail]->len;
293
294                 dev_kfree_skb_irq(priv->tx_skb[tx_tail]);
295                 priv->tx_skb[tx_tail] = NULL;
296
297                 tx_tail = TX_NEXT(tx_tail);
298         }
299         priv->tx_tail = tx_tail;
300 }
301
302 static irqreturn_t moxart_mac_interrupt(int irq, void *dev_id)
303 {
304         struct net_device *ndev = (struct net_device *) dev_id;
305         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
306         unsigned int ists = readl(priv->base + REG_INTERRUPT_STATUS);
307
308         if (ists & XPKT_OK_INT_STS)
309                 moxart_tx_finished(ndev);
310
311         if (ists & RPKT_FINISH) {
312                 if (napi_schedule_prep(&priv->napi)) {
313                         priv->reg_imr &= ~RPKT_FINISH_M;
314                         writel(priv->reg_imr, priv->base + REG_INTERRUPT_MASK);
315                         __napi_schedule(&priv->napi);
316                 }
317         }
318
319         return IRQ_HANDLED;
320 }
321
322 static int moxart_mac_start_xmit(struct sk_buff *skb, struct net_device *ndev)
323 {
324         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
325         void *desc;
326         unsigned int len;
327         unsigned int tx_head = priv->tx_head;
328         u32 txdes1;
329         int ret = NETDEV_TX_BUSY;
330
331         desc = priv->tx_desc_base + (TX_REG_DESC_SIZE * tx_head);
332
333         spin_lock_irq(&priv->txlock);
334         if (moxart_desc_read(desc + TX_REG_OFFSET_DESC0) & TX_DESC0_DMA_OWN) {
335                 net_dbg_ratelimited("no TX space for packet\n");
336                 priv->stats.tx_dropped++;
337                 goto out_unlock;
338         }
339         rmb(); /* ensure data is only read that had TX_DESC0_DMA_OWN cleared */
340
341         len = skb->len > TX_BUF_SIZE ? TX_BUF_SIZE : skb->len;
342
343         priv->tx_mapping[tx_head] = dma_map_single(&ndev->dev, skb->data,
344                                                    len, DMA_TO_DEVICE);
345         if (dma_mapping_error(&ndev->dev, priv->tx_mapping[tx_head])) {
346                 netdev_err(ndev, "DMA mapping error\n");
347                 goto out_unlock;
348         }
349
350         priv->tx_len[tx_head] = len;
351         priv->tx_skb[tx_head] = skb;
352
353         moxart_desc_write(priv->tx_mapping[tx_head],
354                desc + TX_REG_OFFSET_DESC2 + TX_DESC2_ADDRESS_PHYS);
355         moxart_desc_write((uintptr_t)skb->data,
356                desc + TX_REG_OFFSET_DESC2 + TX_DESC2_ADDRESS_VIRT);
357
358         if (skb->len < ETH_ZLEN) {
359                 memset(&skb->data[skb->len],
360                        0, ETH_ZLEN - skb->len);
361                 len = ETH_ZLEN;
362         }
363
364         dma_sync_single_for_device(&ndev->dev, priv->tx_mapping[tx_head],
365                                    priv->tx_buf_size, DMA_TO_DEVICE);
366
367         txdes1 = TX_DESC1_LTS | TX_DESC1_FTS | (len & TX_DESC1_BUF_SIZE_MASK);
368         if (tx_head == TX_DESC_NUM_MASK)
369                 txdes1 |= TX_DESC1_END;
370         moxart_desc_write(txdes1, desc + TX_REG_OFFSET_DESC1);
371         wmb(); /* flush descriptor before transferring ownership */
372         moxart_desc_write(TX_DESC0_DMA_OWN, desc + TX_REG_OFFSET_DESC0);
373
374         /* start to send packet */
375         writel(0xffffffff, priv->base + REG_TX_POLL_DEMAND);
376
377         priv->tx_head = TX_NEXT(tx_head);
378
379         ndev->trans_start = jiffies;
380         ret = NETDEV_TX_OK;
381 out_unlock:
382         spin_unlock_irq(&priv->txlock);
383
384         return ret;
385 }
386
387 static struct net_device_stats *moxart_mac_get_stats(struct net_device *ndev)
388 {
389         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
390
391         return &priv->stats;
392 }
393
394 static void moxart_mac_setmulticast(struct net_device *ndev)
395 {
396         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
397         struct netdev_hw_addr *ha;
398         int crc_val;
399
400         netdev_for_each_mc_addr(ha, ndev) {
401                 crc_val = crc32_le(~0, ha->addr, ETH_ALEN);
402                 crc_val = (crc_val >> 26) & 0x3f;
403                 if (crc_val >= 32) {
404                         writel(readl(priv->base + REG_MCAST_HASH_TABLE1) |
405                                (1UL << (crc_val - 32)),
406                                priv->base + REG_MCAST_HASH_TABLE1);
407                 } else {
408                         writel(readl(priv->base + REG_MCAST_HASH_TABLE0) |
409                                (1UL << crc_val),
410                                priv->base + REG_MCAST_HASH_TABLE0);
411                 }
412         }
413 }
414
415 static void moxart_mac_set_rx_mode(struct net_device *ndev)
416 {
417         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
418
419         spin_lock_irq(&priv->txlock);
420
421         (ndev->flags & IFF_PROMISC) ? (priv->reg_maccr |= RCV_ALL) :
422                                       (priv->reg_maccr &= ~RCV_ALL);
423
424         (ndev->flags & IFF_ALLMULTI) ? (priv->reg_maccr |= RX_MULTIPKT) :
425                                        (priv->reg_maccr &= ~RX_MULTIPKT);
426
427         if ((ndev->flags & IFF_MULTICAST) && netdev_mc_count(ndev)) {
428                 priv->reg_maccr |= HT_MULTI_EN;
429                 moxart_mac_setmulticast(ndev);
430         } else {
431                 priv->reg_maccr &= ~HT_MULTI_EN;
432         }
433
434         writel(priv->reg_maccr, priv->base + REG_MAC_CTRL);
435
436         spin_unlock_irq(&priv->txlock);
437 }
438
439 static struct net_device_ops moxart_netdev_ops = {
440         .ndo_open               = moxart_mac_open,
441         .ndo_stop               = moxart_mac_stop,
442         .ndo_start_xmit         = moxart_mac_start_xmit,
443         .ndo_get_stats          = moxart_mac_get_stats,
444         .ndo_set_rx_mode        = moxart_mac_set_rx_mode,
445         .ndo_set_mac_address    = moxart_set_mac_address,
446         .ndo_validate_addr      = eth_validate_addr,
447         .ndo_change_mtu         = eth_change_mtu,
448 };
449
450 static int moxart_mac_probe(struct platform_device *pdev)
451 {
452         struct device *p_dev = &pdev->dev;
453         struct device_node *node = p_dev->of_node;
454         struct net_device *ndev;
455         struct moxart_mac_priv_t *priv;
456         struct resource *res;
457         unsigned int irq;
458         int ret;
459
460         ndev = alloc_etherdev(sizeof(struct moxart_mac_priv_t));
461         if (!ndev)
462                 return -ENOMEM;
463
464         irq = irq_of_parse_and_map(node, 0);
465         if (irq <= 0) {
466                 netdev_err(ndev, "irq_of_parse_and_map failed\n");
467                 ret = -EINVAL;
468                 goto irq_map_fail;
469         }
470
471         priv = netdev_priv(ndev);
472         priv->ndev = ndev;
473
474         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
475         ndev->base_addr = res->start;
476         priv->base = devm_ioremap_resource(p_dev, res);
477         ret = IS_ERR(priv->base);
478         if (ret) {
479                 dev_err(p_dev, "devm_ioremap_resource failed\n");
480                 goto init_fail;
481         }
482
483         spin_lock_init(&priv->txlock);
484
485         priv->tx_buf_size = TX_BUF_SIZE;
486         priv->rx_buf_size = RX_BUF_SIZE;
487
488         priv->tx_desc_base = dma_alloc_coherent(NULL, TX_REG_DESC_SIZE *
489                                                 TX_DESC_NUM, &priv->tx_base,
490                                                 GFP_DMA | GFP_KERNEL);
491         if (priv->tx_desc_base == NULL) {
492                 ret = -ENOMEM;
493                 goto init_fail;
494         }
495
496         priv->rx_desc_base = dma_alloc_coherent(NULL, RX_REG_DESC_SIZE *
497                                                 RX_DESC_NUM, &priv->rx_base,
498                                                 GFP_DMA | GFP_KERNEL);
499         if (priv->rx_desc_base == NULL) {
500                 ret = -ENOMEM;
501                 goto init_fail;
502         }
503
504         priv->tx_buf_base = kmalloc(priv->tx_buf_size * TX_DESC_NUM,
505                                     GFP_ATOMIC);
506         if (!priv->tx_buf_base) {
507                 ret = -ENOMEM;
508                 goto init_fail;
509         }
510
511         priv->rx_buf_base = kmalloc(priv->rx_buf_size * RX_DESC_NUM,
512                                     GFP_ATOMIC);
513         if (!priv->rx_buf_base) {
514                 ret = -ENOMEM;
515                 goto init_fail;
516         }
517
518         platform_set_drvdata(pdev, ndev);
519
520         ret = devm_request_irq(p_dev, irq, moxart_mac_interrupt, 0,
521                                pdev->name, ndev);
522         if (ret) {
523                 netdev_err(ndev, "devm_request_irq failed\n");
524                 goto init_fail;
525         }
526
527         ndev->netdev_ops = &moxart_netdev_ops;
528         netif_napi_add(ndev, &priv->napi, moxart_rx_poll, RX_DESC_NUM);
529         ndev->priv_flags |= IFF_UNICAST_FLT;
530         ndev->irq = irq;
531
532         SET_NETDEV_DEV(ndev, &pdev->dev);
533
534         ret = register_netdev(ndev);
535         if (ret) {
536                 free_netdev(ndev);
537                 goto init_fail;
538         }
539
540         netdev_dbg(ndev, "%s: IRQ=%d address=%pM\n",
541                    __func__, ndev->irq, ndev->dev_addr);
542
543         return 0;
544
545 init_fail:
546         netdev_err(ndev, "init failed\n");
547         moxart_mac_free_memory(ndev);
548 irq_map_fail:
549         free_netdev(ndev);
550         return ret;
551 }
552
553 static int moxart_remove(struct platform_device *pdev)
554 {
555         struct net_device *ndev = platform_get_drvdata(pdev);
556
557         unregister_netdev(ndev);
558         free_irq(ndev->irq, ndev);
559         moxart_mac_free_memory(ndev);
560         free_netdev(ndev);
561
562         return 0;
563 }
564
565 static const struct of_device_id moxart_mac_match[] = {
566         { .compatible = "moxa,moxart-mac" },
567         { }
568 };
569 MODULE_DEVICE_TABLE(of, moxart_mac_match);
570
571 static struct platform_driver moxart_mac_driver = {
572         .probe  = moxart_mac_probe,
573         .remove = moxart_remove,
574         .driver = {
575                 .name           = "moxart-ethernet",
576                 .of_match_table = moxart_mac_match,
577         },
578 };
579 module_platform_driver(moxart_mac_driver);
580
581 MODULE_DESCRIPTION("MOXART RTL8201CP Ethernet driver");
582 MODULE_LICENSE("GPL v2");
583 MODULE_AUTHOR("Jonas Jensen <jonas.jensen@gmail.com>");