2 * Copyright(c) 2015 EZchip Technologies.
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms and conditions of the GNU General Public License,
6 * version 2, as published by the Free Software Foundation.
8 * This program is distributed in the hope it will be useful, but WITHOUT
9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
13 * The full GNU General Public License is included in this distribution in
14 * the file called "COPYING".
17 #include <linux/module.h>
18 #include <linux/etherdevice.h>
19 #include <linux/of_address.h>
20 #include <linux/of_irq.h>
21 #include <linux/of_net.h>
22 #include <linux/of_platform.h>
25 #define DRV_NAME "nps_mgt_enet"
27 static void nps_enet_clean_rx_fifo(struct net_device *ndev, u32 frame_len)
29 struct nps_enet_priv *priv = netdev_priv(ndev);
30 u32 i, len = DIV_ROUND_UP(frame_len, sizeof(u32));
32 /* Empty Rx FIFO buffer by reading all words */
33 for (i = 0; i < len; i++)
34 nps_enet_reg_get(priv, NPS_ENET_REG_RX_BUF);
37 static void nps_enet_read_rx_fifo(struct net_device *ndev,
38 unsigned char *dst, u32 length)
40 struct nps_enet_priv *priv = netdev_priv(ndev);
41 s32 i, last = length & (sizeof(u32) - 1);
42 u32 *reg = (u32 *)dst, len = length / sizeof(u32);
43 bool dst_is_aligned = IS_ALIGNED((unsigned long)dst, sizeof(u32));
45 /* In case dst is not aligned we need an intermediate buffer */
47 for (i = 0; i < len; i++, reg++)
48 *reg = nps_enet_reg_get(priv, NPS_ENET_REG_RX_BUF);
49 else { /* !dst_is_aligned */
50 for (i = 0; i < len; i++, reg++) {
52 nps_enet_reg_get(priv, NPS_ENET_REG_RX_BUF);
54 /* to accommodate word-unaligned address of "reg"
55 * we have to do memcpy_toio() instead of simple "=".
57 memcpy_toio((void __iomem *)reg, &buf, sizeof(buf));
61 /* copy last bytes (if any) */
63 u32 buf = nps_enet_reg_get(priv, NPS_ENET_REG_RX_BUF);
65 memcpy_toio((void __iomem *)reg, &buf, last);
69 static u32 nps_enet_rx_handler(struct net_device *ndev)
71 u32 frame_len, err = 0;
73 struct nps_enet_priv *priv = netdev_priv(ndev);
75 struct nps_enet_rx_ctl rx_ctrl;
77 rx_ctrl.value = nps_enet_reg_get(priv, NPS_ENET_REG_RX_CTL);
78 frame_len = rx_ctrl.nr;
80 /* Check if we got RX */
84 /* If we got here there is a work for us */
89 ndev->stats.rx_errors++;
93 /* Check Rx CRC error */
95 ndev->stats.rx_crc_errors++;
96 ndev->stats.rx_dropped++;
100 /* Check Frame length Min 64b */
101 if (unlikely(frame_len < ETH_ZLEN)) {
102 ndev->stats.rx_length_errors++;
103 ndev->stats.rx_dropped++;
111 skb = netdev_alloc_skb_ip_align(ndev, frame_len);
112 if (unlikely(!skb)) {
113 ndev->stats.rx_errors++;
114 ndev->stats.rx_dropped++;
118 /* Copy frame from Rx fifo into the skb */
119 nps_enet_read_rx_fifo(ndev, skb->data, frame_len);
121 skb_put(skb, frame_len);
122 skb->protocol = eth_type_trans(skb, ndev);
123 skb->ip_summed = CHECKSUM_UNNECESSARY;
125 ndev->stats.rx_packets++;
126 ndev->stats.rx_bytes += frame_len;
127 netif_receive_skb(skb);
129 goto rx_irq_frame_done;
133 nps_enet_clean_rx_fifo(ndev, frame_len);
136 /* Ack Rx ctrl register */
137 nps_enet_reg_set(priv, NPS_ENET_REG_RX_CTL, 0);
142 static void nps_enet_tx_handler(struct net_device *ndev)
144 struct nps_enet_priv *priv = netdev_priv(ndev);
145 struct nps_enet_tx_ctl tx_ctrl;
147 tx_ctrl.value = nps_enet_reg_get(priv, NPS_ENET_REG_TX_CTL);
149 /* Check if we got TX */
150 if (!priv->tx_packet_sent || tx_ctrl.ct)
153 /* Check Tx transmit error */
154 if (unlikely(tx_ctrl.et)) {
155 ndev->stats.tx_errors++;
157 ndev->stats.tx_packets++;
158 ndev->stats.tx_bytes += tx_ctrl.nt;
161 dev_kfree_skb(priv->tx_skb);
162 priv->tx_packet_sent = false;
164 if (netif_queue_stopped(ndev))
165 netif_wake_queue(ndev);
169 * nps_enet_poll - NAPI poll handler.
170 * @napi: Pointer to napi_struct structure.
171 * @budget: How many frames to process on one call.
173 * returns: Number of processed frames
175 static int nps_enet_poll(struct napi_struct *napi, int budget)
177 struct net_device *ndev = napi->dev;
178 struct nps_enet_priv *priv = netdev_priv(ndev);
179 struct nps_enet_buf_int_enable buf_int_enable;
182 buf_int_enable.rx_rdy = NPS_ENET_ENABLE;
183 buf_int_enable.tx_done = NPS_ENET_ENABLE;
184 nps_enet_tx_handler(ndev);
185 work_done = nps_enet_rx_handler(ndev);
186 if (work_done < budget) {
188 nps_enet_reg_set(priv, NPS_ENET_REG_BUF_INT_ENABLE,
189 buf_int_enable.value);
196 * nps_enet_irq_handler - Global interrupt handler for ENET.
198 * @dev_instance: device instance.
200 * returns: IRQ_HANDLED for all cases.
202 * EZchip ENET has 2 interrupt causes, and depending on bits raised in
203 * CTRL registers we may tell what is a reason for interrupt to fire up.
204 * We got one for RX and the other for TX (completion).
206 static irqreturn_t nps_enet_irq_handler(s32 irq, void *dev_instance)
208 struct net_device *ndev = dev_instance;
209 struct nps_enet_priv *priv = netdev_priv(ndev);
210 struct nps_enet_rx_ctl rx_ctrl;
211 struct nps_enet_tx_ctl tx_ctrl;
213 rx_ctrl.value = nps_enet_reg_get(priv, NPS_ENET_REG_RX_CTL);
214 tx_ctrl.value = nps_enet_reg_get(priv, NPS_ENET_REG_TX_CTL);
216 if ((!tx_ctrl.ct && priv->tx_packet_sent) || rx_ctrl.cr)
217 if (likely(napi_schedule_prep(&priv->napi))) {
218 nps_enet_reg_set(priv, NPS_ENET_REG_BUF_INT_ENABLE, 0);
219 __napi_schedule(&priv->napi);
225 static void nps_enet_set_hw_mac_address(struct net_device *ndev)
227 struct nps_enet_priv *priv = netdev_priv(ndev);
228 struct nps_enet_ge_mac_cfg_1 ge_mac_cfg_1;
229 struct nps_enet_ge_mac_cfg_2 *ge_mac_cfg_2 = &priv->ge_mac_cfg_2;
231 /* set MAC address in HW */
232 ge_mac_cfg_1.octet_0 = ndev->dev_addr[0];
233 ge_mac_cfg_1.octet_1 = ndev->dev_addr[1];
234 ge_mac_cfg_1.octet_2 = ndev->dev_addr[2];
235 ge_mac_cfg_1.octet_3 = ndev->dev_addr[3];
236 ge_mac_cfg_2->octet_4 = ndev->dev_addr[4];
237 ge_mac_cfg_2->octet_5 = ndev->dev_addr[5];
239 nps_enet_reg_set(priv, NPS_ENET_REG_GE_MAC_CFG_1,
242 nps_enet_reg_set(priv, NPS_ENET_REG_GE_MAC_CFG_2,
243 ge_mac_cfg_2->value);
247 * nps_enet_hw_reset - Reset the network device.
248 * @ndev: Pointer to the network device.
250 * This function reset the PCS and TX fifo.
251 * The programming model is to set the relevant reset bits
252 * wait for some time for this to propagate and then unset
253 * the reset bits. This way we ensure that reset procedure
254 * is done successfully by device.
256 static void nps_enet_hw_reset(struct net_device *ndev)
258 struct nps_enet_priv *priv = netdev_priv(ndev);
259 struct nps_enet_ge_rst ge_rst;
260 struct nps_enet_phase_fifo_ctl phase_fifo_ctl;
263 phase_fifo_ctl.value = 0;
264 /* Pcs reset sequence*/
265 ge_rst.gmac_0 = NPS_ENET_ENABLE;
266 nps_enet_reg_set(priv, NPS_ENET_REG_GE_RST, ge_rst.value);
267 usleep_range(10, 20);
269 nps_enet_reg_set(priv, NPS_ENET_REG_GE_RST, ge_rst.value);
271 /* Tx fifo reset sequence */
272 phase_fifo_ctl.rst = NPS_ENET_ENABLE;
273 phase_fifo_ctl.init = NPS_ENET_ENABLE;
274 nps_enet_reg_set(priv, NPS_ENET_REG_PHASE_FIFO_CTL,
275 phase_fifo_ctl.value);
276 usleep_range(10, 20);
277 phase_fifo_ctl.value = 0;
278 nps_enet_reg_set(priv, NPS_ENET_REG_PHASE_FIFO_CTL,
279 phase_fifo_ctl.value);
282 static void nps_enet_hw_enable_control(struct net_device *ndev)
284 struct nps_enet_priv *priv = netdev_priv(ndev);
285 struct nps_enet_ge_mac_cfg_0 ge_mac_cfg_0;
286 struct nps_enet_buf_int_enable buf_int_enable;
287 struct nps_enet_ge_mac_cfg_2 *ge_mac_cfg_2 = &priv->ge_mac_cfg_2;
288 struct nps_enet_ge_mac_cfg_3 *ge_mac_cfg_3 = &priv->ge_mac_cfg_3;
289 s32 max_frame_length;
291 ge_mac_cfg_0.value = 0;
292 buf_int_enable.value = 0;
293 /* Enable Rx and Tx statistics */
294 ge_mac_cfg_2->stat_en = NPS_ENET_GE_MAC_CFG_2_STAT_EN;
296 /* Discard packets with different MAC address */
297 ge_mac_cfg_2->disc_da = NPS_ENET_ENABLE;
299 /* Discard multicast packets */
300 ge_mac_cfg_2->disc_mc = NPS_ENET_ENABLE;
302 nps_enet_reg_set(priv, NPS_ENET_REG_GE_MAC_CFG_2,
303 ge_mac_cfg_2->value);
305 /* Discard Packets bigger than max frame length */
306 max_frame_length = ETH_HLEN + ndev->mtu + ETH_FCS_LEN;
307 if (max_frame_length <= NPS_ENET_MAX_FRAME_LENGTH)
308 ge_mac_cfg_3->max_len = max_frame_length;
310 /* Enable interrupts */
311 buf_int_enable.rx_rdy = NPS_ENET_ENABLE;
312 buf_int_enable.tx_done = NPS_ENET_ENABLE;
313 nps_enet_reg_set(priv, NPS_ENET_REG_BUF_INT_ENABLE,
314 buf_int_enable.value);
316 /* Write device MAC address to HW */
317 nps_enet_set_hw_mac_address(ndev);
319 /* Rx and Tx HW features */
320 ge_mac_cfg_0.tx_pad_en = NPS_ENET_ENABLE;
321 ge_mac_cfg_0.tx_crc_en = NPS_ENET_ENABLE;
322 ge_mac_cfg_0.rx_crc_strip = NPS_ENET_ENABLE;
324 /* IFG configuration */
325 ge_mac_cfg_0.rx_ifg = NPS_ENET_GE_MAC_CFG_0_RX_IFG;
326 ge_mac_cfg_0.tx_ifg = NPS_ENET_GE_MAC_CFG_0_TX_IFG;
328 /* preamble configuration */
329 ge_mac_cfg_0.rx_pr_check_en = NPS_ENET_ENABLE;
330 ge_mac_cfg_0.tx_pr_len = NPS_ENET_GE_MAC_CFG_0_TX_PR_LEN;
332 /* enable flow control frames */
333 ge_mac_cfg_0.tx_fc_en = NPS_ENET_ENABLE;
334 ge_mac_cfg_0.rx_fc_en = NPS_ENET_ENABLE;
335 ge_mac_cfg_0.tx_fc_retr = NPS_ENET_GE_MAC_CFG_0_TX_FC_RETR;
336 ge_mac_cfg_3->cf_drop = NPS_ENET_ENABLE;
338 /* Enable Rx and Tx */
339 ge_mac_cfg_0.rx_en = NPS_ENET_ENABLE;
340 ge_mac_cfg_0.tx_en = NPS_ENET_ENABLE;
342 nps_enet_reg_set(priv, NPS_ENET_REG_GE_MAC_CFG_3,
343 ge_mac_cfg_3->value);
344 nps_enet_reg_set(priv, NPS_ENET_REG_GE_MAC_CFG_0,
348 static void nps_enet_hw_disable_control(struct net_device *ndev)
350 struct nps_enet_priv *priv = netdev_priv(ndev);
352 /* Disable interrupts */
353 nps_enet_reg_set(priv, NPS_ENET_REG_BUF_INT_ENABLE, 0);
355 /* Disable Rx and Tx */
356 nps_enet_reg_set(priv, NPS_ENET_REG_GE_MAC_CFG_0, 0);
359 static void nps_enet_send_frame(struct net_device *ndev,
362 struct nps_enet_priv *priv = netdev_priv(ndev);
363 struct nps_enet_tx_ctl tx_ctrl;
364 short length = skb->len;
365 u32 i, len = DIV_ROUND_UP(length, sizeof(u32));
366 u32 *src = (u32 *)virt_to_phys(skb->data);
367 bool src_is_aligned = IS_ALIGNED((unsigned long)src, sizeof(u32));
370 /* In case src is not aligned we need an intermediate buffer */
372 for (i = 0; i < len; i++, src++)
373 nps_enet_reg_set(priv, NPS_ENET_REG_TX_BUF, *src);
374 else { /* !src_is_aligned */
375 for (i = 0; i < len; i++, src++) {
378 /* to accommodate word-unaligned address of "src"
379 * we have to do memcpy_fromio() instead of simple "="
381 memcpy_fromio(&buf, (void __iomem *)src, sizeof(buf));
382 nps_enet_reg_set(priv, NPS_ENET_REG_TX_BUF, buf);
385 /* Write the length of the Frame */
388 /* Indicate SW is done */
389 priv->tx_packet_sent = true;
390 tx_ctrl.ct = NPS_ENET_ENABLE;
393 nps_enet_reg_set(priv, NPS_ENET_REG_TX_CTL, tx_ctrl.value);
397 * nps_enet_set_mac_address - Set the MAC address for this device.
398 * @ndev: Pointer to net_device structure.
399 * @p: 6 byte Address to be written as MAC address.
401 * This function copies the HW address from the sockaddr structure to the
402 * net_device structure and updates the address in HW.
404 * returns: -EBUSY if the net device is busy or 0 if the address is set
407 static s32 nps_enet_set_mac_address(struct net_device *ndev, void *p)
409 struct sockaddr *addr = p;
412 if (netif_running(ndev))
415 res = eth_mac_addr(ndev, p);
417 ether_addr_copy(ndev->dev_addr, addr->sa_data);
418 nps_enet_set_hw_mac_address(ndev);
425 * nps_enet_set_rx_mode - Change the receive filtering mode.
426 * @ndev: Pointer to the network device.
428 * This function enables/disables promiscuous mode
430 static void nps_enet_set_rx_mode(struct net_device *ndev)
432 struct nps_enet_priv *priv = netdev_priv(ndev);
433 struct nps_enet_ge_mac_cfg_2 ge_mac_cfg_2;
435 ge_mac_cfg_2.value = priv->ge_mac_cfg_2.value;
437 if (ndev->flags & IFF_PROMISC) {
438 ge_mac_cfg_2.disc_da = NPS_ENET_DISABLE;
439 ge_mac_cfg_2.disc_mc = NPS_ENET_DISABLE;
441 ge_mac_cfg_2.disc_da = NPS_ENET_ENABLE;
442 ge_mac_cfg_2.disc_mc = NPS_ENET_ENABLE;
445 nps_enet_reg_set(priv, NPS_ENET_REG_GE_MAC_CFG_2, ge_mac_cfg_2.value);
449 * nps_enet_open - Open the network device.
450 * @ndev: Pointer to the network device.
452 * returns: 0, on success or non-zero error value on failure.
454 * This function sets the MAC address, requests and enables an IRQ
455 * for the ENET device and starts the Tx queue.
457 static s32 nps_enet_open(struct net_device *ndev)
459 struct nps_enet_priv *priv = netdev_priv(ndev);
462 /* Reset private variables */
463 priv->tx_packet_sent = false;
464 priv->ge_mac_cfg_2.value = 0;
465 priv->ge_mac_cfg_3.value = 0;
467 /* ge_mac_cfg_3 default values */
468 priv->ge_mac_cfg_3.rx_ifg_th = NPS_ENET_GE_MAC_CFG_3_RX_IFG_TH;
469 priv->ge_mac_cfg_3.max_len = NPS_ENET_GE_MAC_CFG_3_MAX_LEN;
471 /* Disable HW device */
472 nps_enet_hw_disable_control(ndev);
474 /* irq Rx allocation */
475 err = request_irq(priv->irq, nps_enet_irq_handler,
476 0, "enet-rx-tx", ndev);
480 napi_enable(&priv->napi);
482 /* Enable HW device */
483 nps_enet_hw_reset(ndev);
484 nps_enet_hw_enable_control(ndev);
486 netif_start_queue(ndev);
492 * nps_enet_stop - Close the network device.
493 * @ndev: Pointer to the network device.
495 * This function stops the Tx queue, disables interrupts for the ENET device.
497 static s32 nps_enet_stop(struct net_device *ndev)
499 struct nps_enet_priv *priv = netdev_priv(ndev);
501 napi_disable(&priv->napi);
502 netif_stop_queue(ndev);
503 nps_enet_hw_disable_control(ndev);
504 free_irq(priv->irq, ndev);
510 * nps_enet_start_xmit - Starts the data transmission.
511 * @skb: sk_buff pointer that contains data to be Transmitted.
512 * @ndev: Pointer to net_device structure.
514 * returns: NETDEV_TX_OK, on success
515 * NETDEV_TX_BUSY, if any of the descriptors are not free.
517 * This function is invoked from upper layers to initiate transmission.
519 static netdev_tx_t nps_enet_start_xmit(struct sk_buff *skb,
520 struct net_device *ndev)
522 struct nps_enet_priv *priv = netdev_priv(ndev);
524 /* This driver handles one frame at a time */
525 netif_stop_queue(ndev);
529 nps_enet_send_frame(ndev, skb);
534 #ifdef CONFIG_NET_POLL_CONTROLLER
535 static void nps_enet_poll_controller(struct net_device *ndev)
537 disable_irq(ndev->irq);
538 nps_enet_irq_handler(ndev->irq, ndev);
539 enable_irq(ndev->irq);
543 static const struct net_device_ops nps_netdev_ops = {
544 .ndo_open = nps_enet_open,
545 .ndo_stop = nps_enet_stop,
546 .ndo_start_xmit = nps_enet_start_xmit,
547 .ndo_set_mac_address = nps_enet_set_mac_address,
548 .ndo_set_rx_mode = nps_enet_set_rx_mode,
549 #ifdef CONFIG_NET_POLL_CONTROLLER
550 .ndo_poll_controller = nps_enet_poll_controller,
554 static s32 nps_enet_probe(struct platform_device *pdev)
556 struct device *dev = &pdev->dev;
557 struct net_device *ndev;
558 struct nps_enet_priv *priv;
560 const char *mac_addr;
561 struct resource *res_regs;
566 ndev = alloc_etherdev(sizeof(struct nps_enet_priv));
570 platform_set_drvdata(pdev, ndev);
571 SET_NETDEV_DEV(ndev, dev);
572 priv = netdev_priv(ndev);
574 /* The EZ NET specific entries in the device structure. */
575 ndev->netdev_ops = &nps_netdev_ops;
576 ndev->watchdog_timeo = (400 * HZ / 1000);
577 /* FIXME :: no multicast support yet */
578 ndev->flags &= ~IFF_MULTICAST;
580 res_regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
581 priv->regs_base = devm_ioremap_resource(dev, res_regs);
582 if (IS_ERR(priv->regs_base)) {
583 err = PTR_ERR(priv->regs_base);
586 dev_dbg(dev, "Registers base address is 0x%p\n", priv->regs_base);
588 /* set kernel MAC address to dev */
589 mac_addr = of_get_mac_address(dev->of_node);
591 ether_addr_copy(ndev->dev_addr, mac_addr);
593 eth_hw_addr_random(ndev);
596 priv->irq = platform_get_irq(pdev, 0);
598 dev_err(dev, "failed to retrieve <irq Rx-Tx> value from device tree\n");
603 netif_napi_add(ndev, &priv->napi, nps_enet_poll,
604 NPS_ENET_NAPI_POLL_WEIGHT);
606 /* Register the driver. Should be the last thing in probe */
607 err = register_netdev(ndev);
609 dev_err(dev, "Failed to register ndev for %s, err = 0x%08x\n",
610 ndev->name, (s32)err);
614 dev_info(dev, "(rx/tx=%d)\n", priv->irq);
618 netif_napi_del(&priv->napi);
626 static s32 nps_enet_remove(struct platform_device *pdev)
628 struct net_device *ndev = platform_get_drvdata(pdev);
629 struct nps_enet_priv *priv = netdev_priv(ndev);
631 unregister_netdev(ndev);
633 netif_napi_del(&priv->napi);
638 static const struct of_device_id nps_enet_dt_ids[] = {
639 { .compatible = "ezchip,nps-mgt-enet" },
643 static struct platform_driver nps_enet_driver = {
644 .probe = nps_enet_probe,
645 .remove = nps_enet_remove,
648 .of_match_table = nps_enet_dt_ids,
652 module_platform_driver(nps_enet_driver);
654 MODULE_AUTHOR("EZchip Semiconductor");
655 MODULE_LICENSE("GPL v2");