1 // SPDX-License-Identifier: GPL-2.0-only OR BSD-3-Clause
2 
3 /* Gigabit Ethernet driver for Mellanox BlueField SoC
4  *
5  * Copyright (C) 2020-2021 NVIDIA CORPORATION & AFFILIATES
6  */
7 
8 #include <linux/acpi.h>
9 #include <linux/device.h>
10 #include <linux/dma-mapping.h>
11 #include <linux/etherdevice.h>
12 #include <linux/interrupt.h>
13 #include <linux/iopoll.h>
14 #include <linux/module.h>
15 #include <linux/phy.h>
16 #include <linux/platform_device.h>
17 #include <linux/skbuff.h>
18 
19 #include "mlxbf_gige.h"
20 #include "mlxbf_gige_regs.h"
21 
22 /* Allocate SKB whose payload pointer aligns with the Bluefield
23  * hardware DMA limitation, i.e. DMA operation can't cross
24  * a 4KB boundary.  A maximum packet size of 2KB is assumed in the
25  * alignment formula.  The alignment logic overallocates an SKB,
26  * and then adjusts the headroom so that the SKB data pointer is
27  * naturally aligned to a 2KB boundary.
28  */
29 struct sk_buff *mlxbf_gige_alloc_skb(struct mlxbf_gige *priv,
30 				     unsigned int map_len,
31 				     dma_addr_t *buf_dma,
32 				     enum dma_data_direction dir)
33 {
34 	struct sk_buff *skb;
35 	u64 addr, offset;
36 
37 	/* Overallocate the SKB so that any headroom adjustment (to
38 	 * provide 2KB natural alignment) does not exceed payload area
39 	 */
40 	skb = netdev_alloc_skb(priv->netdev, MLXBF_GIGE_DEFAULT_BUF_SZ * 2);
41 	if (!skb)
42 		return NULL;
43 
44 	/* Adjust the headroom so that skb->data is naturally aligned to
45 	 * a 2KB boundary, which is the maximum packet size supported.
46 	 */
47 	addr = (long)skb->data;
48 	offset = (addr + MLXBF_GIGE_DEFAULT_BUF_SZ - 1) &
49 		~(MLXBF_GIGE_DEFAULT_BUF_SZ - 1);
50 	offset -= addr;
51 	if (offset)
52 		skb_reserve(skb, offset);
53 
54 	/* Return streaming DMA mapping to caller */
55 	*buf_dma = dma_map_single(priv->dev, skb->data, map_len, dir);
56 	if (dma_mapping_error(priv->dev, *buf_dma)) {
57 		dev_kfree_skb(skb);
58 		*buf_dma = (dma_addr_t)0;
59 		return NULL;
60 	}
61 
62 	return skb;
63 }
64 
65 static void mlxbf_gige_initial_mac(struct mlxbf_gige *priv)
66 {
67 	u8 mac[ETH_ALEN];
68 	u64 local_mac;
69 
70 	eth_zero_addr(mac);
71 	mlxbf_gige_get_mac_rx_filter(priv, MLXBF_GIGE_LOCAL_MAC_FILTER_IDX,
72 				     &local_mac);
73 	u64_to_ether_addr(local_mac, mac);
74 
75 	if (is_valid_ether_addr(mac)) {
76 		eth_hw_addr_set(priv->netdev, mac);
77 	} else {
78 		/* Provide a random MAC if for some reason the device has
79 		 * not been configured with a valid MAC address already.
80 		 */
81 		eth_hw_addr_random(priv->netdev);
82 	}
83 
84 	local_mac = ether_addr_to_u64(priv->netdev->dev_addr);
85 	mlxbf_gige_set_mac_rx_filter(priv, MLXBF_GIGE_LOCAL_MAC_FILTER_IDX,
86 				     local_mac);
87 }
88 
89 static void mlxbf_gige_cache_stats(struct mlxbf_gige *priv)
90 {
91 	struct mlxbf_gige_stats *p;
92 
93 	/* Cache stats that will be cleared by clean port operation */
94 	p = &priv->stats;
95 	p->rx_din_dropped_pkts += readq(priv->base +
96 					MLXBF_GIGE_RX_DIN_DROP_COUNTER);
97 	p->rx_filter_passed_pkts += readq(priv->base +
98 					  MLXBF_GIGE_RX_PASS_COUNTER_ALL);
99 	p->rx_filter_discard_pkts += readq(priv->base +
100 					   MLXBF_GIGE_RX_DISC_COUNTER_ALL);
101 }
102 
103 static int mlxbf_gige_clean_port(struct mlxbf_gige *priv)
104 {
105 	u64 control;
106 	u64 temp;
107 	int err;
108 
109 	/* Set the CLEAN_PORT_EN bit to trigger SW reset */
110 	control = readq(priv->base + MLXBF_GIGE_CONTROL);
111 	control |= MLXBF_GIGE_CONTROL_CLEAN_PORT_EN;
112 	writeq(control, priv->base + MLXBF_GIGE_CONTROL);
113 
114 	/* Ensure completion of "clean port" write before polling status */
115 	mb();
116 
117 	err = readq_poll_timeout_atomic(priv->base + MLXBF_GIGE_STATUS, temp,
118 					(temp & MLXBF_GIGE_STATUS_READY),
119 					100, 100000);
120 
121 	/* Clear the CLEAN_PORT_EN bit at end of this loop */
122 	control = readq(priv->base + MLXBF_GIGE_CONTROL);
123 	control &= ~MLXBF_GIGE_CONTROL_CLEAN_PORT_EN;
124 	writeq(control, priv->base + MLXBF_GIGE_CONTROL);
125 
126 	return err;
127 }
128 
129 static int mlxbf_gige_open(struct net_device *netdev)
130 {
131 	struct mlxbf_gige *priv = netdev_priv(netdev);
132 	struct phy_device *phydev = netdev->phydev;
133 	u64 control;
134 	u64 int_en;
135 	int err;
136 
137 	/* Perform general init of GigE block */
138 	control = readq(priv->base + MLXBF_GIGE_CONTROL);
139 	control |= MLXBF_GIGE_CONTROL_PORT_EN;
140 	writeq(control, priv->base + MLXBF_GIGE_CONTROL);
141 
142 	err = mlxbf_gige_request_irqs(priv);
143 	if (err)
144 		return err;
145 	mlxbf_gige_cache_stats(priv);
146 	err = mlxbf_gige_clean_port(priv);
147 	if (err)
148 		goto free_irqs;
149 
150 	/* Clear driver's valid_polarity to match hardware,
151 	 * since the above call to clean_port() resets the
152 	 * receive polarity used by hardware.
153 	 */
154 	priv->valid_polarity = 0;
155 
156 	phy_start(phydev);
157 
158 	err = mlxbf_gige_tx_init(priv);
159 	if (err)
160 		goto free_irqs;
161 	err = mlxbf_gige_rx_init(priv);
162 	if (err)
163 		goto tx_deinit;
164 
165 	netif_napi_add(netdev, &priv->napi, mlxbf_gige_poll);
166 	napi_enable(&priv->napi);
167 	netif_start_queue(netdev);
168 
169 	/* Set bits in INT_EN that we care about */
170 	int_en = MLXBF_GIGE_INT_EN_HW_ACCESS_ERROR |
171 		 MLXBF_GIGE_INT_EN_TX_CHECKSUM_INPUTS |
172 		 MLXBF_GIGE_INT_EN_TX_SMALL_FRAME_SIZE |
173 		 MLXBF_GIGE_INT_EN_TX_PI_CI_EXCEED_WQ_SIZE |
174 		 MLXBF_GIGE_INT_EN_SW_CONFIG_ERROR |
175 		 MLXBF_GIGE_INT_EN_SW_ACCESS_ERROR |
176 		 MLXBF_GIGE_INT_EN_RX_RECEIVE_PACKET;
177 
178 	/* Ensure completion of all initialization before enabling interrupts */
179 	mb();
180 
181 	writeq(int_en, priv->base + MLXBF_GIGE_INT_EN);
182 
183 	return 0;
184 
185 tx_deinit:
186 	mlxbf_gige_tx_deinit(priv);
187 
188 free_irqs:
189 	mlxbf_gige_free_irqs(priv);
190 	return err;
191 }
192 
193 static int mlxbf_gige_stop(struct net_device *netdev)
194 {
195 	struct mlxbf_gige *priv = netdev_priv(netdev);
196 
197 	writeq(0, priv->base + MLXBF_GIGE_INT_EN);
198 	netif_stop_queue(netdev);
199 	napi_disable(&priv->napi);
200 	netif_napi_del(&priv->napi);
201 	mlxbf_gige_free_irqs(priv);
202 
203 	phy_stop(netdev->phydev);
204 
205 	mlxbf_gige_rx_deinit(priv);
206 	mlxbf_gige_tx_deinit(priv);
207 	mlxbf_gige_cache_stats(priv);
208 	mlxbf_gige_clean_port(priv);
209 
210 	return 0;
211 }
212 
213 static int mlxbf_gige_eth_ioctl(struct net_device *netdev,
214 				struct ifreq *ifr, int cmd)
215 {
216 	if (!(netif_running(netdev)))
217 		return -EINVAL;
218 
219 	return phy_mii_ioctl(netdev->phydev, ifr, cmd);
220 }
221 
222 static void mlxbf_gige_set_rx_mode(struct net_device *netdev)
223 {
224 	struct mlxbf_gige *priv = netdev_priv(netdev);
225 	bool new_promisc_enabled;
226 
227 	new_promisc_enabled = netdev->flags & IFF_PROMISC;
228 
229 	/* Only write to the hardware registers if the new setting
230 	 * of promiscuous mode is different from the current one.
231 	 */
232 	if (new_promisc_enabled != priv->promisc_enabled) {
233 		priv->promisc_enabled = new_promisc_enabled;
234 
235 		if (new_promisc_enabled)
236 			mlxbf_gige_enable_promisc(priv);
237 		else
238 			mlxbf_gige_disable_promisc(priv);
239 	}
240 }
241 
242 static void mlxbf_gige_get_stats64(struct net_device *netdev,
243 				   struct rtnl_link_stats64 *stats)
244 {
245 	struct mlxbf_gige *priv = netdev_priv(netdev);
246 
247 	netdev_stats_to_stats64(stats, &netdev->stats);
248 
249 	stats->rx_length_errors = priv->stats.rx_truncate_errors;
250 	stats->rx_fifo_errors = priv->stats.rx_din_dropped_pkts +
251 				readq(priv->base + MLXBF_GIGE_RX_DIN_DROP_COUNTER);
252 	stats->rx_crc_errors = priv->stats.rx_mac_errors;
253 	stats->rx_errors = stats->rx_length_errors +
254 			   stats->rx_fifo_errors +
255 			   stats->rx_crc_errors;
256 
257 	stats->tx_fifo_errors = priv->stats.tx_fifo_full;
258 	stats->tx_errors = stats->tx_fifo_errors;
259 }
260 
261 static const struct net_device_ops mlxbf_gige_netdev_ops = {
262 	.ndo_open		= mlxbf_gige_open,
263 	.ndo_stop		= mlxbf_gige_stop,
264 	.ndo_start_xmit		= mlxbf_gige_start_xmit,
265 	.ndo_set_mac_address	= eth_mac_addr,
266 	.ndo_validate_addr	= eth_validate_addr,
267 	.ndo_eth_ioctl		= mlxbf_gige_eth_ioctl,
268 	.ndo_set_rx_mode        = mlxbf_gige_set_rx_mode,
269 	.ndo_get_stats64        = mlxbf_gige_get_stats64,
270 };
271 
272 static void mlxbf_gige_bf2_adjust_link(struct net_device *netdev)
273 {
274 	struct phy_device *phydev = netdev->phydev;
275 
276 	phy_print_status(phydev);
277 }
278 
279 static void mlxbf_gige_bf3_adjust_link(struct net_device *netdev)
280 {
281 	struct mlxbf_gige *priv = netdev_priv(netdev);
282 	struct phy_device *phydev = netdev->phydev;
283 	u8 sgmii_mode;
284 	u16 ipg_size;
285 	u32 val;
286 
287 	if (phydev->link && phydev->speed != priv->prev_speed) {
288 		switch (phydev->speed) {
289 		case 1000:
290 			ipg_size = MLXBF_GIGE_1G_IPG_SIZE;
291 			sgmii_mode = MLXBF_GIGE_1G_SGMII_MODE;
292 			break;
293 		case 100:
294 			ipg_size = MLXBF_GIGE_100M_IPG_SIZE;
295 			sgmii_mode = MLXBF_GIGE_100M_SGMII_MODE;
296 			break;
297 		case 10:
298 			ipg_size = MLXBF_GIGE_10M_IPG_SIZE;
299 			sgmii_mode = MLXBF_GIGE_10M_SGMII_MODE;
300 			break;
301 		default:
302 			return;
303 		}
304 
305 		val = readl(priv->plu_base + MLXBF_GIGE_PLU_TX_REG0);
306 		val &= ~(MLXBF_GIGE_PLU_TX_IPG_SIZE_MASK | MLXBF_GIGE_PLU_TX_SGMII_MODE_MASK);
307 		val |= FIELD_PREP(MLXBF_GIGE_PLU_TX_IPG_SIZE_MASK, ipg_size);
308 		val |= FIELD_PREP(MLXBF_GIGE_PLU_TX_SGMII_MODE_MASK, sgmii_mode);
309 		writel(val, priv->plu_base + MLXBF_GIGE_PLU_TX_REG0);
310 
311 		val = readl(priv->plu_base + MLXBF_GIGE_PLU_RX_REG0);
312 		val &= ~MLXBF_GIGE_PLU_RX_SGMII_MODE_MASK;
313 		val |= FIELD_PREP(MLXBF_GIGE_PLU_RX_SGMII_MODE_MASK, sgmii_mode);
314 		writel(val, priv->plu_base + MLXBF_GIGE_PLU_RX_REG0);
315 
316 		priv->prev_speed = phydev->speed;
317 	}
318 
319 	phy_print_status(phydev);
320 }
321 
322 static void mlxbf_gige_bf2_set_phy_link_mode(struct phy_device *phydev)
323 {
324 	/* MAC only supports 1000T full duplex mode */
325 	phy_remove_link_mode(phydev, ETHTOOL_LINK_MODE_1000baseT_Half_BIT);
326 	phy_remove_link_mode(phydev, ETHTOOL_LINK_MODE_100baseT_Full_BIT);
327 	phy_remove_link_mode(phydev, ETHTOOL_LINK_MODE_100baseT_Half_BIT);
328 	phy_remove_link_mode(phydev, ETHTOOL_LINK_MODE_10baseT_Full_BIT);
329 	phy_remove_link_mode(phydev, ETHTOOL_LINK_MODE_10baseT_Half_BIT);
330 
331 	/* Only symmetric pause with flow control enabled is supported so no
332 	 * need to negotiate pause.
333 	 */
334 	linkmode_clear_bit(ETHTOOL_LINK_MODE_Pause_BIT, phydev->advertising);
335 	linkmode_clear_bit(ETHTOOL_LINK_MODE_Asym_Pause_BIT, phydev->advertising);
336 }
337 
338 static void mlxbf_gige_bf3_set_phy_link_mode(struct phy_device *phydev)
339 {
340 	/* MAC only supports full duplex mode */
341 	phy_remove_link_mode(phydev, ETHTOOL_LINK_MODE_1000baseT_Half_BIT);
342 	phy_remove_link_mode(phydev, ETHTOOL_LINK_MODE_100baseT_Half_BIT);
343 	phy_remove_link_mode(phydev, ETHTOOL_LINK_MODE_10baseT_Half_BIT);
344 
345 	/* Only symmetric pause with flow control enabled is supported so no
346 	 * need to negotiate pause.
347 	 */
348 	linkmode_clear_bit(ETHTOOL_LINK_MODE_Pause_BIT, phydev->advertising);
349 	linkmode_clear_bit(ETHTOOL_LINK_MODE_Asym_Pause_BIT, phydev->advertising);
350 }
351 
352 static struct mlxbf_gige_link_cfg mlxbf_gige_link_cfgs[] = {
353 	[MLXBF_GIGE_VERSION_BF2] = {
354 		.set_phy_link_mode = mlxbf_gige_bf2_set_phy_link_mode,
355 		.adjust_link = mlxbf_gige_bf2_adjust_link,
356 		.phy_mode = PHY_INTERFACE_MODE_GMII
357 	},
358 	[MLXBF_GIGE_VERSION_BF3] = {
359 		.set_phy_link_mode = mlxbf_gige_bf3_set_phy_link_mode,
360 		.adjust_link = mlxbf_gige_bf3_adjust_link,
361 		.phy_mode = PHY_INTERFACE_MODE_SGMII
362 	}
363 };
364 
365 static int mlxbf_gige_probe(struct platform_device *pdev)
366 {
367 	struct phy_device *phydev;
368 	struct net_device *netdev;
369 	struct mlxbf_gige *priv;
370 	void __iomem *llu_base;
371 	void __iomem *plu_base;
372 	void __iomem *base;
373 	int addr, phy_irq;
374 	int err;
375 
376 	base = devm_platform_ioremap_resource(pdev, MLXBF_GIGE_RES_MAC);
377 	if (IS_ERR(base))
378 		return PTR_ERR(base);
379 
380 	llu_base = devm_platform_ioremap_resource(pdev, MLXBF_GIGE_RES_LLU);
381 	if (IS_ERR(llu_base))
382 		return PTR_ERR(llu_base);
383 
384 	plu_base = devm_platform_ioremap_resource(pdev, MLXBF_GIGE_RES_PLU);
385 	if (IS_ERR(plu_base))
386 		return PTR_ERR(plu_base);
387 
388 	netdev = devm_alloc_etherdev(&pdev->dev, sizeof(*priv));
389 	if (!netdev)
390 		return -ENOMEM;
391 
392 	SET_NETDEV_DEV(netdev, &pdev->dev);
393 	netdev->netdev_ops = &mlxbf_gige_netdev_ops;
394 	netdev->ethtool_ops = &mlxbf_gige_ethtool_ops;
395 	priv = netdev_priv(netdev);
396 	priv->netdev = netdev;
397 
398 	platform_set_drvdata(pdev, priv);
399 	priv->dev = &pdev->dev;
400 	priv->pdev = pdev;
401 
402 	spin_lock_init(&priv->lock);
403 
404 	priv->hw_version = readq(base + MLXBF_GIGE_VERSION);
405 
406 	/* Attach MDIO device */
407 	err = mlxbf_gige_mdio_probe(pdev, priv);
408 	if (err)
409 		return err;
410 
411 	priv->base = base;
412 	priv->llu_base = llu_base;
413 	priv->plu_base = plu_base;
414 
415 	priv->rx_q_entries = MLXBF_GIGE_DEFAULT_RXQ_SZ;
416 	priv->tx_q_entries = MLXBF_GIGE_DEFAULT_TXQ_SZ;
417 
418 	/* Write initial MAC address to hardware */
419 	mlxbf_gige_initial_mac(priv);
420 
421 	err = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
422 	if (err) {
423 		dev_err(&pdev->dev, "DMA configuration failed: 0x%x\n", err);
424 		goto out;
425 	}
426 
427 	priv->error_irq = platform_get_irq(pdev, MLXBF_GIGE_ERROR_INTR_IDX);
428 	priv->rx_irq = platform_get_irq(pdev, MLXBF_GIGE_RECEIVE_PKT_INTR_IDX);
429 	priv->llu_plu_irq = platform_get_irq(pdev, MLXBF_GIGE_LLU_PLU_INTR_IDX);
430 
431 	phy_irq = acpi_dev_gpio_irq_get_by(ACPI_COMPANION(&pdev->dev), "phy-gpios", 0);
432 	if (phy_irq < 0) {
433 		dev_err(&pdev->dev, "Error getting PHY irq. Use polling instead");
434 		phy_irq = PHY_POLL;
435 	}
436 
437 	phydev = phy_find_first(priv->mdiobus);
438 	if (!phydev) {
439 		err = -ENODEV;
440 		goto out;
441 	}
442 
443 	addr = phydev->mdio.addr;
444 	priv->mdiobus->irq[addr] = phy_irq;
445 	phydev->irq = phy_irq;
446 
447 	err = phy_connect_direct(netdev, phydev,
448 				 mlxbf_gige_link_cfgs[priv->hw_version].adjust_link,
449 				 mlxbf_gige_link_cfgs[priv->hw_version].phy_mode);
450 	if (err) {
451 		dev_err(&pdev->dev, "Could not attach to PHY\n");
452 		goto out;
453 	}
454 
455 	mlxbf_gige_link_cfgs[priv->hw_version].set_phy_link_mode(phydev);
456 
457 	/* Display information about attached PHY device */
458 	phy_attached_info(phydev);
459 
460 	err = register_netdev(netdev);
461 	if (err) {
462 		dev_err(&pdev->dev, "Failed to register netdev\n");
463 		phy_disconnect(phydev);
464 		goto out;
465 	}
466 
467 	return 0;
468 
469 out:
470 	mlxbf_gige_mdio_remove(priv);
471 	return err;
472 }
473 
474 static int mlxbf_gige_remove(struct platform_device *pdev)
475 {
476 	struct mlxbf_gige *priv = platform_get_drvdata(pdev);
477 
478 	unregister_netdev(priv->netdev);
479 	phy_disconnect(priv->netdev->phydev);
480 	mlxbf_gige_mdio_remove(priv);
481 	platform_set_drvdata(pdev, NULL);
482 
483 	return 0;
484 }
485 
486 static void mlxbf_gige_shutdown(struct platform_device *pdev)
487 {
488 	struct mlxbf_gige *priv = platform_get_drvdata(pdev);
489 
490 	writeq(0, priv->base + MLXBF_GIGE_INT_EN);
491 	mlxbf_gige_clean_port(priv);
492 }
493 
494 static const struct acpi_device_id __maybe_unused mlxbf_gige_acpi_match[] = {
495 	{ "MLNXBF17", 0 },
496 	{},
497 };
498 MODULE_DEVICE_TABLE(acpi, mlxbf_gige_acpi_match);
499 
500 static struct platform_driver mlxbf_gige_driver = {
501 	.probe = mlxbf_gige_probe,
502 	.remove = mlxbf_gige_remove,
503 	.shutdown = mlxbf_gige_shutdown,
504 	.driver = {
505 		.name = KBUILD_MODNAME,
506 		.acpi_match_table = ACPI_PTR(mlxbf_gige_acpi_match),
507 	},
508 };
509 
510 module_platform_driver(mlxbf_gige_driver);
511 
512 MODULE_DESCRIPTION("Mellanox BlueField SoC Gigabit Ethernet Driver");
513 MODULE_AUTHOR("David Thompson <davthompson@nvidia.com>");
514 MODULE_AUTHOR("Asmaa Mnebhi <asmaa@nvidia.com>");
515 MODULE_LICENSE("Dual BSD/GPL");
516