xref: /openbmc/linux/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c (revision c51d39010a1bccc9c1294e2d7c00005aefeb2b5c)
1 /*******************************************************************************
2   This is the driver for the ST MAC 10/100/1000 on-chip Ethernet controllers.
3   ST Ethernet IPs are built around a Synopsys IP Core.
4 
5 	Copyright(C) 2007-2011 STMicroelectronics Ltd
6 
7   This program is free software; you can redistribute it and/or modify it
8   under the terms and conditions of the GNU General Public License,
9   version 2, as published by the Free Software Foundation.
10 
11   This program is distributed in the hope it will be useful, but WITHOUT
12   ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13   FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
14   more details.
15 
16   You should have received a copy of the GNU General Public License along with
17   this program; if not, write to the Free Software Foundation, Inc.,
18   51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
19 
20   The full GNU General Public License is included in this distribution in
21   the file called "COPYING".
22 
23   Author: Giuseppe Cavallaro <peppe.cavallaro@st.com>
24 
25   Documentation available at:
26 	http://www.stlinux.com
27   Support available at:
28 	https://bugzilla.stlinux.com/
29 *******************************************************************************/
30 
31 #include <linux/clk.h>
32 #include <linux/kernel.h>
33 #include <linux/interrupt.h>
34 #include <linux/ip.h>
35 #include <linux/tcp.h>
36 #include <linux/skbuff.h>
37 #include <linux/ethtool.h>
38 #include <linux/if_ether.h>
39 #include <linux/crc32.h>
40 #include <linux/mii.h>
41 #include <linux/if.h>
42 #include <linux/if_vlan.h>
43 #include <linux/dma-mapping.h>
44 #include <linux/slab.h>
45 #include <linux/prefetch.h>
46 #include <linux/pinctrl/consumer.h>
47 #ifdef CONFIG_DEBUG_FS
48 #include <linux/debugfs.h>
49 #include <linux/seq_file.h>
50 #endif /* CONFIG_DEBUG_FS */
51 #include <linux/net_tstamp.h>
52 #include "stmmac_ptp.h"
53 #include "stmmac.h"
54 #include <linux/reset.h>
55 #include <linux/of_mdio.h>
56 #include "dwmac1000.h"
57 
58 #define STMMAC_ALIGN(x)	L1_CACHE_ALIGN(x)
59 #define	TSO_MAX_BUFF_SIZE	(SZ_16K - 1)
60 
61 /* Module parameters */
62 #define TX_TIMEO	5000
63 static int watchdog = TX_TIMEO;
64 module_param(watchdog, int, S_IRUGO | S_IWUSR);
65 MODULE_PARM_DESC(watchdog, "Transmit timeout in milliseconds (default 5s)");
66 
67 static int debug = -1;
68 module_param(debug, int, S_IRUGO | S_IWUSR);
69 MODULE_PARM_DESC(debug, "Message Level (-1: default, 0: no output, 16: all)");
70 
71 static int phyaddr = -1;
72 module_param(phyaddr, int, S_IRUGO);
73 MODULE_PARM_DESC(phyaddr, "Physical device address");
74 
75 #define STMMAC_TX_THRESH	(DMA_TX_SIZE / 4)
76 #define STMMAC_RX_THRESH	(DMA_RX_SIZE / 4)
77 
78 static int flow_ctrl = FLOW_OFF;
79 module_param(flow_ctrl, int, S_IRUGO | S_IWUSR);
80 MODULE_PARM_DESC(flow_ctrl, "Flow control ability [on/off]");
81 
82 static int pause = PAUSE_TIME;
83 module_param(pause, int, S_IRUGO | S_IWUSR);
84 MODULE_PARM_DESC(pause, "Flow Control Pause Time");
85 
86 #define TC_DEFAULT 64
87 static int tc = TC_DEFAULT;
88 module_param(tc, int, S_IRUGO | S_IWUSR);
89 MODULE_PARM_DESC(tc, "DMA threshold control value");
90 
91 #define	DEFAULT_BUFSIZE	1536
92 static int buf_sz = DEFAULT_BUFSIZE;
93 module_param(buf_sz, int, S_IRUGO | S_IWUSR);
94 MODULE_PARM_DESC(buf_sz, "DMA buffer size");
95 
96 #define	STMMAC_RX_COPYBREAK	256
97 
98 static const u32 default_msg_level = (NETIF_MSG_DRV | NETIF_MSG_PROBE |
99 				      NETIF_MSG_LINK | NETIF_MSG_IFUP |
100 				      NETIF_MSG_IFDOWN | NETIF_MSG_TIMER);
101 
102 #define STMMAC_DEFAULT_LPI_TIMER	1000
103 static int eee_timer = STMMAC_DEFAULT_LPI_TIMER;
104 module_param(eee_timer, int, S_IRUGO | S_IWUSR);
105 MODULE_PARM_DESC(eee_timer, "LPI tx expiration time in msec");
106 #define STMMAC_LPI_T(x) (jiffies + msecs_to_jiffies(x))
107 
108 /* By default the driver will use the ring mode to manage tx and rx descriptors,
109  * but allow user to force to use the chain instead of the ring
110  */
111 static unsigned int chain_mode;
112 module_param(chain_mode, int, S_IRUGO);
113 MODULE_PARM_DESC(chain_mode, "To use chain instead of ring mode");
114 
115 static irqreturn_t stmmac_interrupt(int irq, void *dev_id);
116 
117 #ifdef CONFIG_DEBUG_FS
118 static int stmmac_init_fs(struct net_device *dev);
119 static void stmmac_exit_fs(struct net_device *dev);
120 #endif
121 
122 #define STMMAC_COAL_TIMER(x) (jiffies + usecs_to_jiffies(x))
123 
124 /**
125  * stmmac_verify_args - verify the driver parameters.
126  * Description: it checks the driver parameters and set a default in case of
127  * errors.
128  */
129 static void stmmac_verify_args(void)
130 {
131 	if (unlikely(watchdog < 0))
132 		watchdog = TX_TIMEO;
133 	if (unlikely((buf_sz < DEFAULT_BUFSIZE) || (buf_sz > BUF_SIZE_16KiB)))
134 		buf_sz = DEFAULT_BUFSIZE;
135 	if (unlikely(flow_ctrl > 1))
136 		flow_ctrl = FLOW_AUTO;
137 	else if (likely(flow_ctrl < 0))
138 		flow_ctrl = FLOW_OFF;
139 	if (unlikely((pause < 0) || (pause > 0xffff)))
140 		pause = PAUSE_TIME;
141 	if (eee_timer < 0)
142 		eee_timer = STMMAC_DEFAULT_LPI_TIMER;
143 }
144 
145 /**
146  * stmmac_clk_csr_set - dynamically set the MDC clock
147  * @priv: driver private structure
148  * Description: this is to dynamically set the MDC clock according to the csr
149  * clock input.
150  * Note:
151  *	If a specific clk_csr value is passed from the platform
152  *	this means that the CSR Clock Range selection cannot be
153  *	changed at run-time and it is fixed (as reported in the driver
154  *	documentation). Viceversa the driver will try to set the MDC
155  *	clock dynamically according to the actual clock input.
156  */
157 static void stmmac_clk_csr_set(struct stmmac_priv *priv)
158 {
159 	u32 clk_rate;
160 
161 	clk_rate = clk_get_rate(priv->stmmac_clk);
162 
163 	/* Platform provided default clk_csr would be assumed valid
164 	 * for all other cases except for the below mentioned ones.
165 	 * For values higher than the IEEE 802.3 specified frequency
166 	 * we can not estimate the proper divider as it is not known
167 	 * the frequency of clk_csr_i. So we do not change the default
168 	 * divider.
169 	 */
170 	if (!(priv->clk_csr & MAC_CSR_H_FRQ_MASK)) {
171 		if (clk_rate < CSR_F_35M)
172 			priv->clk_csr = STMMAC_CSR_20_35M;
173 		else if ((clk_rate >= CSR_F_35M) && (clk_rate < CSR_F_60M))
174 			priv->clk_csr = STMMAC_CSR_35_60M;
175 		else if ((clk_rate >= CSR_F_60M) && (clk_rate < CSR_F_100M))
176 			priv->clk_csr = STMMAC_CSR_60_100M;
177 		else if ((clk_rate >= CSR_F_100M) && (clk_rate < CSR_F_150M))
178 			priv->clk_csr = STMMAC_CSR_100_150M;
179 		else if ((clk_rate >= CSR_F_150M) && (clk_rate < CSR_F_250M))
180 			priv->clk_csr = STMMAC_CSR_150_250M;
181 		else if ((clk_rate >= CSR_F_250M) && (clk_rate < CSR_F_300M))
182 			priv->clk_csr = STMMAC_CSR_250_300M;
183 	}
184 }
185 
186 static void print_pkt(unsigned char *buf, int len)
187 {
188 	pr_debug("len = %d byte, buf addr: 0x%p\n", len, buf);
189 	print_hex_dump_bytes("", DUMP_PREFIX_OFFSET, buf, len);
190 }
191 
192 static inline u32 stmmac_tx_avail(struct stmmac_priv *priv)
193 {
194 	unsigned avail;
195 
196 	if (priv->dirty_tx > priv->cur_tx)
197 		avail = priv->dirty_tx - priv->cur_tx - 1;
198 	else
199 		avail = DMA_TX_SIZE - priv->cur_tx + priv->dirty_tx - 1;
200 
201 	return avail;
202 }
203 
204 static inline u32 stmmac_rx_dirty(struct stmmac_priv *priv)
205 {
206 	unsigned dirty;
207 
208 	if (priv->dirty_rx <= priv->cur_rx)
209 		dirty = priv->cur_rx - priv->dirty_rx;
210 	else
211 		dirty = DMA_RX_SIZE - priv->dirty_rx + priv->cur_rx;
212 
213 	return dirty;
214 }
215 
216 /**
217  * stmmac_hw_fix_mac_speed - callback for speed selection
218  * @priv: driver private structure
219  * Description: on some platforms (e.g. ST), some HW system configuraton
220  * registers have to be set according to the link speed negotiated.
221  */
222 static inline void stmmac_hw_fix_mac_speed(struct stmmac_priv *priv)
223 {
224 	struct net_device *ndev = priv->dev;
225 	struct phy_device *phydev = ndev->phydev;
226 
227 	if (likely(priv->plat->fix_mac_speed))
228 		priv->plat->fix_mac_speed(priv->plat->bsp_priv, phydev->speed);
229 }
230 
231 /**
232  * stmmac_enable_eee_mode - check and enter in LPI mode
233  * @priv: driver private structure
234  * Description: this function is to verify and enter in LPI mode in case of
235  * EEE.
236  */
237 static void stmmac_enable_eee_mode(struct stmmac_priv *priv)
238 {
239 	/* Check and enter in LPI mode */
240 	if ((priv->dirty_tx == priv->cur_tx) &&
241 	    (priv->tx_path_in_lpi_mode == false))
242 		priv->hw->mac->set_eee_mode(priv->hw);
243 }
244 
245 /**
246  * stmmac_disable_eee_mode - disable and exit from LPI mode
247  * @priv: driver private structure
248  * Description: this function is to exit and disable EEE in case of
249  * LPI state is true. This is called by the xmit.
250  */
251 void stmmac_disable_eee_mode(struct stmmac_priv *priv)
252 {
253 	priv->hw->mac->reset_eee_mode(priv->hw);
254 	del_timer_sync(&priv->eee_ctrl_timer);
255 	priv->tx_path_in_lpi_mode = false;
256 }
257 
258 /**
259  * stmmac_eee_ctrl_timer - EEE TX SW timer.
260  * @arg : data hook
261  * Description:
262  *  if there is no data transfer and if we are not in LPI state,
263  *  then MAC Transmitter can be moved to LPI state.
264  */
265 static void stmmac_eee_ctrl_timer(unsigned long arg)
266 {
267 	struct stmmac_priv *priv = (struct stmmac_priv *)arg;
268 
269 	stmmac_enable_eee_mode(priv);
270 	mod_timer(&priv->eee_ctrl_timer, STMMAC_LPI_T(eee_timer));
271 }
272 
273 /**
274  * stmmac_eee_init - init EEE
275  * @priv: driver private structure
276  * Description:
277  *  if the GMAC supports the EEE (from the HW cap reg) and the phy device
278  *  can also manage EEE, this function enable the LPI state and start related
279  *  timer.
280  */
281 bool stmmac_eee_init(struct stmmac_priv *priv)
282 {
283 	struct net_device *ndev = priv->dev;
284 	unsigned long flags;
285 	bool ret = false;
286 
287 	/* Using PCS we cannot dial with the phy registers at this stage
288 	 * so we do not support extra feature like EEE.
289 	 */
290 	if ((priv->hw->pcs == STMMAC_PCS_RGMII) ||
291 	    (priv->hw->pcs == STMMAC_PCS_TBI) ||
292 	    (priv->hw->pcs == STMMAC_PCS_RTBI))
293 		goto out;
294 
295 	/* MAC core supports the EEE feature. */
296 	if (priv->dma_cap.eee) {
297 		int tx_lpi_timer = priv->tx_lpi_timer;
298 
299 		/* Check if the PHY supports EEE */
300 		if (phy_init_eee(ndev->phydev, 1)) {
301 			/* To manage at run-time if the EEE cannot be supported
302 			 * anymore (for example because the lp caps have been
303 			 * changed).
304 			 * In that case the driver disable own timers.
305 			 */
306 			spin_lock_irqsave(&priv->lock, flags);
307 			if (priv->eee_active) {
308 				netdev_dbg(priv->dev, "disable EEE\n");
309 				del_timer_sync(&priv->eee_ctrl_timer);
310 				priv->hw->mac->set_eee_timer(priv->hw, 0,
311 							     tx_lpi_timer);
312 			}
313 			priv->eee_active = 0;
314 			spin_unlock_irqrestore(&priv->lock, flags);
315 			goto out;
316 		}
317 		/* Activate the EEE and start timers */
318 		spin_lock_irqsave(&priv->lock, flags);
319 		if (!priv->eee_active) {
320 			priv->eee_active = 1;
321 			setup_timer(&priv->eee_ctrl_timer,
322 				    stmmac_eee_ctrl_timer,
323 				    (unsigned long)priv);
324 			mod_timer(&priv->eee_ctrl_timer,
325 				  STMMAC_LPI_T(eee_timer));
326 
327 			priv->hw->mac->set_eee_timer(priv->hw,
328 						     STMMAC_DEFAULT_LIT_LS,
329 						     tx_lpi_timer);
330 		}
331 		/* Set HW EEE according to the speed */
332 		priv->hw->mac->set_eee_pls(priv->hw, ndev->phydev->link);
333 
334 		ret = true;
335 		spin_unlock_irqrestore(&priv->lock, flags);
336 
337 		netdev_dbg(priv->dev, "Energy-Efficient Ethernet initialized\n");
338 	}
339 out:
340 	return ret;
341 }
342 
343 /* stmmac_get_tx_hwtstamp - get HW TX timestamps
344  * @priv: driver private structure
345  * @p : descriptor pointer
346  * @skb : the socket buffer
347  * Description :
348  * This function will read timestamp from the descriptor & pass it to stack.
349  * and also perform some sanity checks.
350  */
351 static void stmmac_get_tx_hwtstamp(struct stmmac_priv *priv,
352 				   struct dma_desc *p, struct sk_buff *skb)
353 {
354 	struct skb_shared_hwtstamps shhwtstamp;
355 	u64 ns;
356 
357 	if (!priv->hwts_tx_en)
358 		return;
359 
360 	/* exit if skb doesn't support hw tstamp */
361 	if (likely(!skb || !(skb_shinfo(skb)->tx_flags & SKBTX_IN_PROGRESS)))
362 		return;
363 
364 	/* check tx tstamp status */
365 	if (!priv->hw->desc->get_tx_timestamp_status(p)) {
366 		/* get the valid tstamp */
367 		ns = priv->hw->desc->get_timestamp(p, priv->adv_ts);
368 
369 		memset(&shhwtstamp, 0, sizeof(struct skb_shared_hwtstamps));
370 		shhwtstamp.hwtstamp = ns_to_ktime(ns);
371 
372 		netdev_info(priv->dev, "get valid TX hw timestamp %llu\n", ns);
373 		/* pass tstamp to stack */
374 		skb_tstamp_tx(skb, &shhwtstamp);
375 	}
376 
377 	return;
378 }
379 
380 /* stmmac_get_rx_hwtstamp - get HW RX timestamps
381  * @priv: driver private structure
382  * @p : descriptor pointer
383  * @np : next descriptor pointer
384  * @skb : the socket buffer
385  * Description :
386  * This function will read received packet's timestamp from the descriptor
387  * and pass it to stack. It also perform some sanity checks.
388  */
389 static void stmmac_get_rx_hwtstamp(struct stmmac_priv *priv, struct dma_desc *p,
390 				   struct dma_desc *np, struct sk_buff *skb)
391 {
392 	struct skb_shared_hwtstamps *shhwtstamp = NULL;
393 	u64 ns;
394 
395 	if (!priv->hwts_rx_en)
396 		return;
397 
398 	/* Check if timestamp is available */
399 	if (!priv->hw->desc->get_rx_timestamp_status(p, priv->adv_ts)) {
400 		/* For GMAC4, the valid timestamp is from CTX next desc. */
401 		if (priv->plat->has_gmac4)
402 			ns = priv->hw->desc->get_timestamp(np, priv->adv_ts);
403 		else
404 			ns = priv->hw->desc->get_timestamp(p, priv->adv_ts);
405 
406 		netdev_info(priv->dev, "get valid RX hw timestamp %llu\n", ns);
407 		shhwtstamp = skb_hwtstamps(skb);
408 		memset(shhwtstamp, 0, sizeof(struct skb_shared_hwtstamps));
409 		shhwtstamp->hwtstamp = ns_to_ktime(ns);
410 	} else  {
411 		netdev_err(priv->dev, "cannot get RX hw timestamp\n");
412 	}
413 }
414 
415 /**
416  *  stmmac_hwtstamp_ioctl - control hardware timestamping.
417  *  @dev: device pointer.
418  *  @ifr: An IOCTL specefic structure, that can contain a pointer to
419  *  a proprietary structure used to pass information to the driver.
420  *  Description:
421  *  This function configures the MAC to enable/disable both outgoing(TX)
422  *  and incoming(RX) packets time stamping based on user input.
423  *  Return Value:
424  *  0 on success and an appropriate -ve integer on failure.
425  */
426 static int stmmac_hwtstamp_ioctl(struct net_device *dev, struct ifreq *ifr)
427 {
428 	struct stmmac_priv *priv = netdev_priv(dev);
429 	struct hwtstamp_config config;
430 	struct timespec64 now;
431 	u64 temp = 0;
432 	u32 ptp_v2 = 0;
433 	u32 tstamp_all = 0;
434 	u32 ptp_over_ipv4_udp = 0;
435 	u32 ptp_over_ipv6_udp = 0;
436 	u32 ptp_over_ethernet = 0;
437 	u32 snap_type_sel = 0;
438 	u32 ts_master_en = 0;
439 	u32 ts_event_en = 0;
440 	u32 value = 0;
441 	u32 sec_inc;
442 
443 	if (!(priv->dma_cap.time_stamp || priv->adv_ts)) {
444 		netdev_alert(priv->dev, "No support for HW time stamping\n");
445 		priv->hwts_tx_en = 0;
446 		priv->hwts_rx_en = 0;
447 
448 		return -EOPNOTSUPP;
449 	}
450 
451 	if (copy_from_user(&config, ifr->ifr_data,
452 			   sizeof(struct hwtstamp_config)))
453 		return -EFAULT;
454 
455 	netdev_dbg(priv->dev, "%s config flags:0x%x, tx_type:0x%x, rx_filter:0x%x\n",
456 		   __func__, config.flags, config.tx_type, config.rx_filter);
457 
458 	/* reserved for future extensions */
459 	if (config.flags)
460 		return -EINVAL;
461 
462 	if (config.tx_type != HWTSTAMP_TX_OFF &&
463 	    config.tx_type != HWTSTAMP_TX_ON)
464 		return -ERANGE;
465 
466 	if (priv->adv_ts) {
467 		switch (config.rx_filter) {
468 		case HWTSTAMP_FILTER_NONE:
469 			/* time stamp no incoming packet at all */
470 			config.rx_filter = HWTSTAMP_FILTER_NONE;
471 			break;
472 
473 		case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
474 			/* PTP v1, UDP, any kind of event packet */
475 			config.rx_filter = HWTSTAMP_FILTER_PTP_V1_L4_EVENT;
476 			/* take time stamp for all event messages */
477 			snap_type_sel = PTP_TCR_SNAPTYPSEL_1;
478 
479 			ptp_over_ipv4_udp = PTP_TCR_TSIPV4ENA;
480 			ptp_over_ipv6_udp = PTP_TCR_TSIPV6ENA;
481 			break;
482 
483 		case HWTSTAMP_FILTER_PTP_V1_L4_SYNC:
484 			/* PTP v1, UDP, Sync packet */
485 			config.rx_filter = HWTSTAMP_FILTER_PTP_V1_L4_SYNC;
486 			/* take time stamp for SYNC messages only */
487 			ts_event_en = PTP_TCR_TSEVNTENA;
488 
489 			ptp_over_ipv4_udp = PTP_TCR_TSIPV4ENA;
490 			ptp_over_ipv6_udp = PTP_TCR_TSIPV6ENA;
491 			break;
492 
493 		case HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ:
494 			/* PTP v1, UDP, Delay_req packet */
495 			config.rx_filter = HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ;
496 			/* take time stamp for Delay_Req messages only */
497 			ts_master_en = PTP_TCR_TSMSTRENA;
498 			ts_event_en = PTP_TCR_TSEVNTENA;
499 
500 			ptp_over_ipv4_udp = PTP_TCR_TSIPV4ENA;
501 			ptp_over_ipv6_udp = PTP_TCR_TSIPV6ENA;
502 			break;
503 
504 		case HWTSTAMP_FILTER_PTP_V2_L4_EVENT:
505 			/* PTP v2, UDP, any kind of event packet */
506 			config.rx_filter = HWTSTAMP_FILTER_PTP_V2_L4_EVENT;
507 			ptp_v2 = PTP_TCR_TSVER2ENA;
508 			/* take time stamp for all event messages */
509 			snap_type_sel = PTP_TCR_SNAPTYPSEL_1;
510 
511 			ptp_over_ipv4_udp = PTP_TCR_TSIPV4ENA;
512 			ptp_over_ipv6_udp = PTP_TCR_TSIPV6ENA;
513 			break;
514 
515 		case HWTSTAMP_FILTER_PTP_V2_L4_SYNC:
516 			/* PTP v2, UDP, Sync packet */
517 			config.rx_filter = HWTSTAMP_FILTER_PTP_V2_L4_SYNC;
518 			ptp_v2 = PTP_TCR_TSVER2ENA;
519 			/* take time stamp for SYNC messages only */
520 			ts_event_en = PTP_TCR_TSEVNTENA;
521 
522 			ptp_over_ipv4_udp = PTP_TCR_TSIPV4ENA;
523 			ptp_over_ipv6_udp = PTP_TCR_TSIPV6ENA;
524 			break;
525 
526 		case HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ:
527 			/* PTP v2, UDP, Delay_req packet */
528 			config.rx_filter = HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ;
529 			ptp_v2 = PTP_TCR_TSVER2ENA;
530 			/* take time stamp for Delay_Req messages only */
531 			ts_master_en = PTP_TCR_TSMSTRENA;
532 			ts_event_en = PTP_TCR_TSEVNTENA;
533 
534 			ptp_over_ipv4_udp = PTP_TCR_TSIPV4ENA;
535 			ptp_over_ipv6_udp = PTP_TCR_TSIPV6ENA;
536 			break;
537 
538 		case HWTSTAMP_FILTER_PTP_V2_EVENT:
539 			/* PTP v2/802.AS1 any layer, any kind of event packet */
540 			config.rx_filter = HWTSTAMP_FILTER_PTP_V2_EVENT;
541 			ptp_v2 = PTP_TCR_TSVER2ENA;
542 			/* take time stamp for all event messages */
543 			snap_type_sel = PTP_TCR_SNAPTYPSEL_1;
544 
545 			ptp_over_ipv4_udp = PTP_TCR_TSIPV4ENA;
546 			ptp_over_ipv6_udp = PTP_TCR_TSIPV6ENA;
547 			ptp_over_ethernet = PTP_TCR_TSIPENA;
548 			break;
549 
550 		case HWTSTAMP_FILTER_PTP_V2_SYNC:
551 			/* PTP v2/802.AS1, any layer, Sync packet */
552 			config.rx_filter = HWTSTAMP_FILTER_PTP_V2_SYNC;
553 			ptp_v2 = PTP_TCR_TSVER2ENA;
554 			/* take time stamp for SYNC messages only */
555 			ts_event_en = PTP_TCR_TSEVNTENA;
556 
557 			ptp_over_ipv4_udp = PTP_TCR_TSIPV4ENA;
558 			ptp_over_ipv6_udp = PTP_TCR_TSIPV6ENA;
559 			ptp_over_ethernet = PTP_TCR_TSIPENA;
560 			break;
561 
562 		case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
563 			/* PTP v2/802.AS1, any layer, Delay_req packet */
564 			config.rx_filter = HWTSTAMP_FILTER_PTP_V2_DELAY_REQ;
565 			ptp_v2 = PTP_TCR_TSVER2ENA;
566 			/* take time stamp for Delay_Req messages only */
567 			ts_master_en = PTP_TCR_TSMSTRENA;
568 			ts_event_en = PTP_TCR_TSEVNTENA;
569 
570 			ptp_over_ipv4_udp = PTP_TCR_TSIPV4ENA;
571 			ptp_over_ipv6_udp = PTP_TCR_TSIPV6ENA;
572 			ptp_over_ethernet = PTP_TCR_TSIPENA;
573 			break;
574 
575 		case HWTSTAMP_FILTER_ALL:
576 			/* time stamp any incoming packet */
577 			config.rx_filter = HWTSTAMP_FILTER_ALL;
578 			tstamp_all = PTP_TCR_TSENALL;
579 			break;
580 
581 		default:
582 			return -ERANGE;
583 		}
584 	} else {
585 		switch (config.rx_filter) {
586 		case HWTSTAMP_FILTER_NONE:
587 			config.rx_filter = HWTSTAMP_FILTER_NONE;
588 			break;
589 		default:
590 			/* PTP v1, UDP, any kind of event packet */
591 			config.rx_filter = HWTSTAMP_FILTER_PTP_V1_L4_EVENT;
592 			break;
593 		}
594 	}
595 	priv->hwts_rx_en = ((config.rx_filter == HWTSTAMP_FILTER_NONE) ? 0 : 1);
596 	priv->hwts_tx_en = config.tx_type == HWTSTAMP_TX_ON;
597 
598 	if (!priv->hwts_tx_en && !priv->hwts_rx_en)
599 		priv->hw->ptp->config_hw_tstamping(priv->ptpaddr, 0);
600 	else {
601 		value = (PTP_TCR_TSENA | PTP_TCR_TSCFUPDT | PTP_TCR_TSCTRLSSR |
602 			 tstamp_all | ptp_v2 | ptp_over_ethernet |
603 			 ptp_over_ipv6_udp | ptp_over_ipv4_udp | ts_event_en |
604 			 ts_master_en | snap_type_sel);
605 		priv->hw->ptp->config_hw_tstamping(priv->ptpaddr, value);
606 
607 		/* program Sub Second Increment reg */
608 		sec_inc = priv->hw->ptp->config_sub_second_increment(
609 			priv->ptpaddr, priv->clk_ptp_rate,
610 			priv->plat->has_gmac4);
611 		temp = div_u64(1000000000ULL, sec_inc);
612 
613 		/* calculate default added value:
614 		 * formula is :
615 		 * addend = (2^32)/freq_div_ratio;
616 		 * where, freq_div_ratio = 1e9ns/sec_inc
617 		 */
618 		temp = (u64)(temp << 32);
619 		priv->default_addend = div_u64(temp, priv->clk_ptp_rate);
620 		priv->hw->ptp->config_addend(priv->ptpaddr,
621 					     priv->default_addend);
622 
623 		/* initialize system time */
624 		ktime_get_real_ts64(&now);
625 
626 		/* lower 32 bits of tv_sec are safe until y2106 */
627 		priv->hw->ptp->init_systime(priv->ptpaddr, (u32)now.tv_sec,
628 					    now.tv_nsec);
629 	}
630 
631 	return copy_to_user(ifr->ifr_data, &config,
632 			    sizeof(struct hwtstamp_config)) ? -EFAULT : 0;
633 }
634 
635 /**
636  * stmmac_init_ptp - init PTP
637  * @priv: driver private structure
638  * Description: this is to verify if the HW supports the PTPv1 or PTPv2.
639  * This is done by looking at the HW cap. register.
640  * This function also registers the ptp driver.
641  */
642 static int stmmac_init_ptp(struct stmmac_priv *priv)
643 {
644 	if (!(priv->dma_cap.time_stamp || priv->dma_cap.atime_stamp))
645 		return -EOPNOTSUPP;
646 
647 	/* Fall-back to main clock in case of no PTP ref is passed */
648 	priv->clk_ptp_ref = devm_clk_get(priv->device, "clk_ptp_ref");
649 	if (IS_ERR(priv->clk_ptp_ref)) {
650 		priv->clk_ptp_rate = clk_get_rate(priv->stmmac_clk);
651 		priv->clk_ptp_ref = NULL;
652 		netdev_dbg(priv->dev, "PTP uses main clock\n");
653 	} else {
654 		clk_prepare_enable(priv->clk_ptp_ref);
655 		priv->clk_ptp_rate = clk_get_rate(priv->clk_ptp_ref);
656 		netdev_dbg(priv->dev, "PTP rate %d\n", priv->clk_ptp_rate);
657 	}
658 
659 	priv->adv_ts = 0;
660 	/* Check if adv_ts can be enabled for dwmac 4.x core */
661 	if (priv->plat->has_gmac4 && priv->dma_cap.atime_stamp)
662 		priv->adv_ts = 1;
663 	/* Dwmac 3.x core with extend_desc can support adv_ts */
664 	else if (priv->extend_desc && priv->dma_cap.atime_stamp)
665 		priv->adv_ts = 1;
666 
667 	if (priv->dma_cap.time_stamp)
668 		netdev_info(priv->dev, "IEEE 1588-2002 Timestamp supported\n");
669 
670 	if (priv->adv_ts)
671 		netdev_info(priv->dev,
672 			    "IEEE 1588-2008 Advanced Timestamp supported\n");
673 
674 	priv->hw->ptp = &stmmac_ptp;
675 	priv->hwts_tx_en = 0;
676 	priv->hwts_rx_en = 0;
677 
678 	stmmac_ptp_register(priv);
679 
680 	return 0;
681 }
682 
683 static void stmmac_release_ptp(struct stmmac_priv *priv)
684 {
685 	if (priv->clk_ptp_ref)
686 		clk_disable_unprepare(priv->clk_ptp_ref);
687 	stmmac_ptp_unregister(priv);
688 }
689 
690 /**
691  * stmmac_adjust_link - adjusts the link parameters
692  * @dev: net device structure
693  * Description: this is the helper called by the physical abstraction layer
694  * drivers to communicate the phy link status. According the speed and duplex
695  * this driver can invoke registered glue-logic as well.
696  * It also invoke the eee initialization because it could happen when switch
697  * on different networks (that are eee capable).
698  */
699 static void stmmac_adjust_link(struct net_device *dev)
700 {
701 	struct stmmac_priv *priv = netdev_priv(dev);
702 	struct phy_device *phydev = dev->phydev;
703 	unsigned long flags;
704 	int new_state = 0;
705 	unsigned int fc = priv->flow_ctrl, pause_time = priv->pause;
706 
707 	if (phydev == NULL)
708 		return;
709 
710 	spin_lock_irqsave(&priv->lock, flags);
711 
712 	if (phydev->link) {
713 		u32 ctrl = readl(priv->ioaddr + MAC_CTRL_REG);
714 
715 		/* Now we make sure that we can be in full duplex mode.
716 		 * If not, we operate in half-duplex mode. */
717 		if (phydev->duplex != priv->oldduplex) {
718 			new_state = 1;
719 			if (!(phydev->duplex))
720 				ctrl &= ~priv->hw->link.duplex;
721 			else
722 				ctrl |= priv->hw->link.duplex;
723 			priv->oldduplex = phydev->duplex;
724 		}
725 		/* Flow Control operation */
726 		if (phydev->pause)
727 			priv->hw->mac->flow_ctrl(priv->hw, phydev->duplex,
728 						 fc, pause_time);
729 
730 		if (phydev->speed != priv->speed) {
731 			new_state = 1;
732 			switch (phydev->speed) {
733 			case 1000:
734 				if (likely((priv->plat->has_gmac) ||
735 					   (priv->plat->has_gmac4)))
736 					ctrl &= ~priv->hw->link.port;
737 				stmmac_hw_fix_mac_speed(priv);
738 				break;
739 			case 100:
740 			case 10:
741 				if (likely((priv->plat->has_gmac) ||
742 					   (priv->plat->has_gmac4))) {
743 					ctrl |= priv->hw->link.port;
744 					if (phydev->speed == SPEED_100) {
745 						ctrl |= priv->hw->link.speed;
746 					} else {
747 						ctrl &= ~(priv->hw->link.speed);
748 					}
749 				} else {
750 					ctrl &= ~priv->hw->link.port;
751 				}
752 				stmmac_hw_fix_mac_speed(priv);
753 				break;
754 			default:
755 				netif_warn(priv, link, priv->dev,
756 					   "Speed (%d) not 10/100\n",
757 					   phydev->speed);
758 				break;
759 			}
760 
761 			priv->speed = phydev->speed;
762 		}
763 
764 		writel(ctrl, priv->ioaddr + MAC_CTRL_REG);
765 
766 		if (!priv->oldlink) {
767 			new_state = 1;
768 			priv->oldlink = 1;
769 		}
770 	} else if (priv->oldlink) {
771 		new_state = 1;
772 		priv->oldlink = 0;
773 		priv->speed = 0;
774 		priv->oldduplex = -1;
775 	}
776 
777 	if (new_state && netif_msg_link(priv))
778 		phy_print_status(phydev);
779 
780 	spin_unlock_irqrestore(&priv->lock, flags);
781 
782 	if (phydev->is_pseudo_fixed_link)
783 		/* Stop PHY layer to call the hook to adjust the link in case
784 		 * of a switch is attached to the stmmac driver.
785 		 */
786 		phydev->irq = PHY_IGNORE_INTERRUPT;
787 	else
788 		/* At this stage, init the EEE if supported.
789 		 * Never called in case of fixed_link.
790 		 */
791 		priv->eee_enabled = stmmac_eee_init(priv);
792 }
793 
794 /**
795  * stmmac_check_pcs_mode - verify if RGMII/SGMII is supported
796  * @priv: driver private structure
797  * Description: this is to verify if the HW supports the PCS.
798  * Physical Coding Sublayer (PCS) interface that can be used when the MAC is
799  * configured for the TBI, RTBI, or SGMII PHY interface.
800  */
801 static void stmmac_check_pcs_mode(struct stmmac_priv *priv)
802 {
803 	int interface = priv->plat->interface;
804 
805 	if (priv->dma_cap.pcs) {
806 		if ((interface == PHY_INTERFACE_MODE_RGMII) ||
807 		    (interface == PHY_INTERFACE_MODE_RGMII_ID) ||
808 		    (interface == PHY_INTERFACE_MODE_RGMII_RXID) ||
809 		    (interface == PHY_INTERFACE_MODE_RGMII_TXID)) {
810 			netdev_dbg(priv->dev, "PCS RGMII support enabled\n");
811 			priv->hw->pcs = STMMAC_PCS_RGMII;
812 		} else if (interface == PHY_INTERFACE_MODE_SGMII) {
813 			netdev_dbg(priv->dev, "PCS SGMII support enabled\n");
814 			priv->hw->pcs = STMMAC_PCS_SGMII;
815 		}
816 	}
817 }
818 
819 /**
820  * stmmac_init_phy - PHY initialization
821  * @dev: net device structure
822  * Description: it initializes the driver's PHY state, and attaches the PHY
823  * to the mac driver.
824  *  Return value:
825  *  0 on success
826  */
827 static int stmmac_init_phy(struct net_device *dev)
828 {
829 	struct stmmac_priv *priv = netdev_priv(dev);
830 	struct phy_device *phydev;
831 	char phy_id_fmt[MII_BUS_ID_SIZE + 3];
832 	char bus_id[MII_BUS_ID_SIZE];
833 	int interface = priv->plat->interface;
834 	int max_speed = priv->plat->max_speed;
835 	priv->oldlink = 0;
836 	priv->speed = 0;
837 	priv->oldduplex = -1;
838 
839 	if (priv->plat->phy_node) {
840 		phydev = of_phy_connect(dev, priv->plat->phy_node,
841 					&stmmac_adjust_link, 0, interface);
842 	} else {
843 		snprintf(bus_id, MII_BUS_ID_SIZE, "stmmac-%x",
844 			 priv->plat->bus_id);
845 
846 		snprintf(phy_id_fmt, MII_BUS_ID_SIZE + 3, PHY_ID_FMT, bus_id,
847 			 priv->plat->phy_addr);
848 		netdev_dbg(priv->dev, "%s: trying to attach to %s\n", __func__,
849 			   phy_id_fmt);
850 
851 		phydev = phy_connect(dev, phy_id_fmt, &stmmac_adjust_link,
852 				     interface);
853 	}
854 
855 	if (IS_ERR_OR_NULL(phydev)) {
856 		netdev_err(priv->dev, "Could not attach to PHY\n");
857 		if (!phydev)
858 			return -ENODEV;
859 
860 		return PTR_ERR(phydev);
861 	}
862 
863 	/* Stop Advertising 1000BASE Capability if interface is not GMII */
864 	if ((interface == PHY_INTERFACE_MODE_MII) ||
865 	    (interface == PHY_INTERFACE_MODE_RMII) ||
866 		(max_speed < 1000 && max_speed > 0))
867 		phydev->advertising &= ~(SUPPORTED_1000baseT_Half |
868 					 SUPPORTED_1000baseT_Full);
869 
870 	/*
871 	 * Broken HW is sometimes missing the pull-up resistor on the
872 	 * MDIO line, which results in reads to non-existent devices returning
873 	 * 0 rather than 0xffff. Catch this here and treat 0 as a non-existent
874 	 * device as well.
875 	 * Note: phydev->phy_id is the result of reading the UID PHY registers.
876 	 */
877 	if (!priv->plat->phy_node && phydev->phy_id == 0) {
878 		phy_disconnect(phydev);
879 		return -ENODEV;
880 	}
881 
882 	/* stmmac_adjust_link will change this to PHY_IGNORE_INTERRUPT to avoid
883 	 * subsequent PHY polling, make sure we force a link transition if
884 	 * we have a UP/DOWN/UP transition
885 	 */
886 	if (phydev->is_pseudo_fixed_link)
887 		phydev->irq = PHY_POLL;
888 
889 	netdev_dbg(priv->dev, "%s: attached to PHY (UID 0x%x) Link = %d\n",
890 		   __func__, phydev->phy_id, phydev->link);
891 
892 	return 0;
893 }
894 
895 static void stmmac_display_rings(struct stmmac_priv *priv)
896 {
897 	void *head_rx, *head_tx;
898 
899 	if (priv->extend_desc) {
900 		head_rx = (void *)priv->dma_erx;
901 		head_tx = (void *)priv->dma_etx;
902 	} else {
903 		head_rx = (void *)priv->dma_rx;
904 		head_tx = (void *)priv->dma_tx;
905 	}
906 
907 	/* Display Rx ring */
908 	priv->hw->desc->display_ring(head_rx, DMA_RX_SIZE, true);
909 	/* Display Tx ring */
910 	priv->hw->desc->display_ring(head_tx, DMA_TX_SIZE, false);
911 }
912 
913 static int stmmac_set_bfsize(int mtu, int bufsize)
914 {
915 	int ret = bufsize;
916 
917 	if (mtu >= BUF_SIZE_4KiB)
918 		ret = BUF_SIZE_8KiB;
919 	else if (mtu >= BUF_SIZE_2KiB)
920 		ret = BUF_SIZE_4KiB;
921 	else if (mtu > DEFAULT_BUFSIZE)
922 		ret = BUF_SIZE_2KiB;
923 	else
924 		ret = DEFAULT_BUFSIZE;
925 
926 	return ret;
927 }
928 
929 /**
930  * stmmac_clear_descriptors - clear descriptors
931  * @priv: driver private structure
932  * Description: this function is called to clear the tx and rx descriptors
933  * in case of both basic and extended descriptors are used.
934  */
935 static void stmmac_clear_descriptors(struct stmmac_priv *priv)
936 {
937 	int i;
938 
939 	/* Clear the Rx/Tx descriptors */
940 	for (i = 0; i < DMA_RX_SIZE; i++)
941 		if (priv->extend_desc)
942 			priv->hw->desc->init_rx_desc(&priv->dma_erx[i].basic,
943 						     priv->use_riwt, priv->mode,
944 						     (i == DMA_RX_SIZE - 1));
945 		else
946 			priv->hw->desc->init_rx_desc(&priv->dma_rx[i],
947 						     priv->use_riwt, priv->mode,
948 						     (i == DMA_RX_SIZE - 1));
949 	for (i = 0; i < DMA_TX_SIZE; i++)
950 		if (priv->extend_desc)
951 			priv->hw->desc->init_tx_desc(&priv->dma_etx[i].basic,
952 						     priv->mode,
953 						     (i == DMA_TX_SIZE - 1));
954 		else
955 			priv->hw->desc->init_tx_desc(&priv->dma_tx[i],
956 						     priv->mode,
957 						     (i == DMA_TX_SIZE - 1));
958 }
959 
960 /**
961  * stmmac_init_rx_buffers - init the RX descriptor buffer.
962  * @priv: driver private structure
963  * @p: descriptor pointer
964  * @i: descriptor index
965  * @flags: gfp flag.
966  * Description: this function is called to allocate a receive buffer, perform
967  * the DMA mapping and init the descriptor.
968  */
969 static int stmmac_init_rx_buffers(struct stmmac_priv *priv, struct dma_desc *p,
970 				  int i, gfp_t flags)
971 {
972 	struct sk_buff *skb;
973 
974 	skb = __netdev_alloc_skb_ip_align(priv->dev, priv->dma_buf_sz, flags);
975 	if (!skb) {
976 		netdev_err(priv->dev,
977 			   "%s: Rx init fails; skb is NULL\n", __func__);
978 		return -ENOMEM;
979 	}
980 	priv->rx_skbuff[i] = skb;
981 	priv->rx_skbuff_dma[i] = dma_map_single(priv->device, skb->data,
982 						priv->dma_buf_sz,
983 						DMA_FROM_DEVICE);
984 	if (dma_mapping_error(priv->device, priv->rx_skbuff_dma[i])) {
985 		netdev_err(priv->dev, "%s: DMA mapping error\n", __func__);
986 		dev_kfree_skb_any(skb);
987 		return -EINVAL;
988 	}
989 
990 	if (priv->synopsys_id >= DWMAC_CORE_4_00)
991 		p->des0 = cpu_to_le32(priv->rx_skbuff_dma[i]);
992 	else
993 		p->des2 = cpu_to_le32(priv->rx_skbuff_dma[i]);
994 
995 	if ((priv->hw->mode->init_desc3) &&
996 	    (priv->dma_buf_sz == BUF_SIZE_16KiB))
997 		priv->hw->mode->init_desc3(p);
998 
999 	return 0;
1000 }
1001 
1002 static void stmmac_free_rx_buffers(struct stmmac_priv *priv, int i)
1003 {
1004 	if (priv->rx_skbuff[i]) {
1005 		dma_unmap_single(priv->device, priv->rx_skbuff_dma[i],
1006 				 priv->dma_buf_sz, DMA_FROM_DEVICE);
1007 		dev_kfree_skb_any(priv->rx_skbuff[i]);
1008 	}
1009 	priv->rx_skbuff[i] = NULL;
1010 }
1011 
1012 /**
1013  * init_dma_desc_rings - init the RX/TX descriptor rings
1014  * @dev: net device structure
1015  * @flags: gfp flag.
1016  * Description: this function initializes the DMA RX/TX descriptors
1017  * and allocates the socket buffers. It suppors the chained and ring
1018  * modes.
1019  */
1020 static int init_dma_desc_rings(struct net_device *dev, gfp_t flags)
1021 {
1022 	int i;
1023 	struct stmmac_priv *priv = netdev_priv(dev);
1024 	unsigned int bfsize = 0;
1025 	int ret = -ENOMEM;
1026 
1027 	if (priv->hw->mode->set_16kib_bfsize)
1028 		bfsize = priv->hw->mode->set_16kib_bfsize(dev->mtu);
1029 
1030 	if (bfsize < BUF_SIZE_16KiB)
1031 		bfsize = stmmac_set_bfsize(dev->mtu, priv->dma_buf_sz);
1032 
1033 	priv->dma_buf_sz = bfsize;
1034 
1035 	netif_dbg(priv, probe, priv->dev,
1036 		  "(%s) dma_rx_phy=0x%08x dma_tx_phy=0x%08x\n",
1037 		  __func__, (u32)priv->dma_rx_phy, (u32)priv->dma_tx_phy);
1038 
1039 	/* RX INITIALIZATION */
1040 	netif_dbg(priv, probe, priv->dev,
1041 		  "SKB addresses:\nskb\t\tskb data\tdma data\n");
1042 
1043 	for (i = 0; i < DMA_RX_SIZE; i++) {
1044 		struct dma_desc *p;
1045 		if (priv->extend_desc)
1046 			p = &((priv->dma_erx + i)->basic);
1047 		else
1048 			p = priv->dma_rx + i;
1049 
1050 		ret = stmmac_init_rx_buffers(priv, p, i, flags);
1051 		if (ret)
1052 			goto err_init_rx_buffers;
1053 
1054 		netif_dbg(priv, probe, priv->dev, "[%p]\t[%p]\t[%x]\n",
1055 			  priv->rx_skbuff[i], priv->rx_skbuff[i]->data,
1056 			  (unsigned int)priv->rx_skbuff_dma[i]);
1057 	}
1058 	priv->cur_rx = 0;
1059 	priv->dirty_rx = (unsigned int)(i - DMA_RX_SIZE);
1060 	buf_sz = bfsize;
1061 
1062 	/* Setup the chained descriptor addresses */
1063 	if (priv->mode == STMMAC_CHAIN_MODE) {
1064 		if (priv->extend_desc) {
1065 			priv->hw->mode->init(priv->dma_erx, priv->dma_rx_phy,
1066 					     DMA_RX_SIZE, 1);
1067 			priv->hw->mode->init(priv->dma_etx, priv->dma_tx_phy,
1068 					     DMA_TX_SIZE, 1);
1069 		} else {
1070 			priv->hw->mode->init(priv->dma_rx, priv->dma_rx_phy,
1071 					     DMA_RX_SIZE, 0);
1072 			priv->hw->mode->init(priv->dma_tx, priv->dma_tx_phy,
1073 					     DMA_TX_SIZE, 0);
1074 		}
1075 	}
1076 
1077 	/* TX INITIALIZATION */
1078 	for (i = 0; i < DMA_TX_SIZE; i++) {
1079 		struct dma_desc *p;
1080 		if (priv->extend_desc)
1081 			p = &((priv->dma_etx + i)->basic);
1082 		else
1083 			p = priv->dma_tx + i;
1084 
1085 		if (priv->synopsys_id >= DWMAC_CORE_4_00) {
1086 			p->des0 = 0;
1087 			p->des1 = 0;
1088 			p->des2 = 0;
1089 			p->des3 = 0;
1090 		} else {
1091 			p->des2 = 0;
1092 		}
1093 
1094 		priv->tx_skbuff_dma[i].buf = 0;
1095 		priv->tx_skbuff_dma[i].map_as_page = false;
1096 		priv->tx_skbuff_dma[i].len = 0;
1097 		priv->tx_skbuff_dma[i].last_segment = false;
1098 		priv->tx_skbuff[i] = NULL;
1099 	}
1100 
1101 	priv->dirty_tx = 0;
1102 	priv->cur_tx = 0;
1103 	netdev_reset_queue(priv->dev);
1104 
1105 	stmmac_clear_descriptors(priv);
1106 
1107 	if (netif_msg_hw(priv))
1108 		stmmac_display_rings(priv);
1109 
1110 	return 0;
1111 err_init_rx_buffers:
1112 	while (--i >= 0)
1113 		stmmac_free_rx_buffers(priv, i);
1114 	return ret;
1115 }
1116 
1117 static void dma_free_rx_skbufs(struct stmmac_priv *priv)
1118 {
1119 	int i;
1120 
1121 	for (i = 0; i < DMA_RX_SIZE; i++)
1122 		stmmac_free_rx_buffers(priv, i);
1123 }
1124 
1125 static void dma_free_tx_skbufs(struct stmmac_priv *priv)
1126 {
1127 	int i;
1128 
1129 	for (i = 0; i < DMA_TX_SIZE; i++) {
1130 		struct dma_desc *p;
1131 
1132 		if (priv->extend_desc)
1133 			p = &((priv->dma_etx + i)->basic);
1134 		else
1135 			p = priv->dma_tx + i;
1136 
1137 		if (priv->tx_skbuff_dma[i].buf) {
1138 			if (priv->tx_skbuff_dma[i].map_as_page)
1139 				dma_unmap_page(priv->device,
1140 					       priv->tx_skbuff_dma[i].buf,
1141 					       priv->tx_skbuff_dma[i].len,
1142 					       DMA_TO_DEVICE);
1143 			else
1144 				dma_unmap_single(priv->device,
1145 						 priv->tx_skbuff_dma[i].buf,
1146 						 priv->tx_skbuff_dma[i].len,
1147 						 DMA_TO_DEVICE);
1148 		}
1149 
1150 		if (priv->tx_skbuff[i] != NULL) {
1151 			dev_kfree_skb_any(priv->tx_skbuff[i]);
1152 			priv->tx_skbuff[i] = NULL;
1153 			priv->tx_skbuff_dma[i].buf = 0;
1154 			priv->tx_skbuff_dma[i].map_as_page = false;
1155 		}
1156 	}
1157 }
1158 
1159 /**
1160  * alloc_dma_desc_resources - alloc TX/RX resources.
1161  * @priv: private structure
1162  * Description: according to which descriptor can be used (extend or basic)
1163  * this function allocates the resources for TX and RX paths. In case of
1164  * reception, for example, it pre-allocated the RX socket buffer in order to
1165  * allow zero-copy mechanism.
1166  */
1167 static int alloc_dma_desc_resources(struct stmmac_priv *priv)
1168 {
1169 	int ret = -ENOMEM;
1170 
1171 	priv->rx_skbuff_dma = kmalloc_array(DMA_RX_SIZE, sizeof(dma_addr_t),
1172 					    GFP_KERNEL);
1173 	if (!priv->rx_skbuff_dma)
1174 		return -ENOMEM;
1175 
1176 	priv->rx_skbuff = kmalloc_array(DMA_RX_SIZE, sizeof(struct sk_buff *),
1177 					GFP_KERNEL);
1178 	if (!priv->rx_skbuff)
1179 		goto err_rx_skbuff;
1180 
1181 	priv->tx_skbuff_dma = kmalloc_array(DMA_TX_SIZE,
1182 					    sizeof(*priv->tx_skbuff_dma),
1183 					    GFP_KERNEL);
1184 	if (!priv->tx_skbuff_dma)
1185 		goto err_tx_skbuff_dma;
1186 
1187 	priv->tx_skbuff = kmalloc_array(DMA_TX_SIZE, sizeof(struct sk_buff *),
1188 					GFP_KERNEL);
1189 	if (!priv->tx_skbuff)
1190 		goto err_tx_skbuff;
1191 
1192 	if (priv->extend_desc) {
1193 		priv->dma_erx = dma_zalloc_coherent(priv->device, DMA_RX_SIZE *
1194 						    sizeof(struct
1195 							   dma_extended_desc),
1196 						    &priv->dma_rx_phy,
1197 						    GFP_KERNEL);
1198 		if (!priv->dma_erx)
1199 			goto err_dma;
1200 
1201 		priv->dma_etx = dma_zalloc_coherent(priv->device, DMA_TX_SIZE *
1202 						    sizeof(struct
1203 							   dma_extended_desc),
1204 						    &priv->dma_tx_phy,
1205 						    GFP_KERNEL);
1206 		if (!priv->dma_etx) {
1207 			dma_free_coherent(priv->device, DMA_RX_SIZE *
1208 					  sizeof(struct dma_extended_desc),
1209 					  priv->dma_erx, priv->dma_rx_phy);
1210 			goto err_dma;
1211 		}
1212 	} else {
1213 		priv->dma_rx = dma_zalloc_coherent(priv->device, DMA_RX_SIZE *
1214 						   sizeof(struct dma_desc),
1215 						   &priv->dma_rx_phy,
1216 						   GFP_KERNEL);
1217 		if (!priv->dma_rx)
1218 			goto err_dma;
1219 
1220 		priv->dma_tx = dma_zalloc_coherent(priv->device, DMA_TX_SIZE *
1221 						   sizeof(struct dma_desc),
1222 						   &priv->dma_tx_phy,
1223 						   GFP_KERNEL);
1224 		if (!priv->dma_tx) {
1225 			dma_free_coherent(priv->device, DMA_RX_SIZE *
1226 					  sizeof(struct dma_desc),
1227 					  priv->dma_rx, priv->dma_rx_phy);
1228 			goto err_dma;
1229 		}
1230 	}
1231 
1232 	return 0;
1233 
1234 err_dma:
1235 	kfree(priv->tx_skbuff);
1236 err_tx_skbuff:
1237 	kfree(priv->tx_skbuff_dma);
1238 err_tx_skbuff_dma:
1239 	kfree(priv->rx_skbuff);
1240 err_rx_skbuff:
1241 	kfree(priv->rx_skbuff_dma);
1242 	return ret;
1243 }
1244 
1245 static void free_dma_desc_resources(struct stmmac_priv *priv)
1246 {
1247 	/* Release the DMA TX/RX socket buffers */
1248 	dma_free_rx_skbufs(priv);
1249 	dma_free_tx_skbufs(priv);
1250 
1251 	/* Free DMA regions of consistent memory previously allocated */
1252 	if (!priv->extend_desc) {
1253 		dma_free_coherent(priv->device,
1254 				  DMA_TX_SIZE * sizeof(struct dma_desc),
1255 				  priv->dma_tx, priv->dma_tx_phy);
1256 		dma_free_coherent(priv->device,
1257 				  DMA_RX_SIZE * sizeof(struct dma_desc),
1258 				  priv->dma_rx, priv->dma_rx_phy);
1259 	} else {
1260 		dma_free_coherent(priv->device, DMA_TX_SIZE *
1261 				  sizeof(struct dma_extended_desc),
1262 				  priv->dma_etx, priv->dma_tx_phy);
1263 		dma_free_coherent(priv->device, DMA_RX_SIZE *
1264 				  sizeof(struct dma_extended_desc),
1265 				  priv->dma_erx, priv->dma_rx_phy);
1266 	}
1267 	kfree(priv->rx_skbuff_dma);
1268 	kfree(priv->rx_skbuff);
1269 	kfree(priv->tx_skbuff_dma);
1270 	kfree(priv->tx_skbuff);
1271 }
1272 
1273 /**
1274  *  stmmac_dma_operation_mode - HW DMA operation mode
1275  *  @priv: driver private structure
1276  *  Description: it is used for configuring the DMA operation mode register in
1277  *  order to program the tx/rx DMA thresholds or Store-And-Forward mode.
1278  */
1279 static void stmmac_dma_operation_mode(struct stmmac_priv *priv)
1280 {
1281 	int rxfifosz = priv->plat->rx_fifo_size;
1282 
1283 	if (priv->plat->force_thresh_dma_mode)
1284 		priv->hw->dma->dma_mode(priv->ioaddr, tc, tc, rxfifosz);
1285 	else if (priv->plat->force_sf_dma_mode || priv->plat->tx_coe) {
1286 		/*
1287 		 * In case of GMAC, SF mode can be enabled
1288 		 * to perform the TX COE in HW. This depends on:
1289 		 * 1) TX COE if actually supported
1290 		 * 2) There is no bugged Jumbo frame support
1291 		 *    that needs to not insert csum in the TDES.
1292 		 */
1293 		priv->hw->dma->dma_mode(priv->ioaddr, SF_DMA_MODE, SF_DMA_MODE,
1294 					rxfifosz);
1295 		priv->xstats.threshold = SF_DMA_MODE;
1296 	} else
1297 		priv->hw->dma->dma_mode(priv->ioaddr, tc, SF_DMA_MODE,
1298 					rxfifosz);
1299 }
1300 
1301 /**
1302  * stmmac_tx_clean - to manage the transmission completion
1303  * @priv: driver private structure
1304  * Description: it reclaims the transmit resources after transmission completes.
1305  */
1306 static void stmmac_tx_clean(struct stmmac_priv *priv)
1307 {
1308 	unsigned int bytes_compl = 0, pkts_compl = 0;
1309 	unsigned int entry = priv->dirty_tx;
1310 
1311 	spin_lock(&priv->tx_lock);
1312 
1313 	priv->xstats.tx_clean++;
1314 
1315 	while (entry != priv->cur_tx) {
1316 		struct sk_buff *skb = priv->tx_skbuff[entry];
1317 		struct dma_desc *p;
1318 		int status;
1319 
1320 		if (priv->extend_desc)
1321 			p = (struct dma_desc *)(priv->dma_etx + entry);
1322 		else
1323 			p = priv->dma_tx + entry;
1324 
1325 		status = priv->hw->desc->tx_status(&priv->dev->stats,
1326 						      &priv->xstats, p,
1327 						      priv->ioaddr);
1328 		/* Check if the descriptor is owned by the DMA */
1329 		if (unlikely(status & tx_dma_own))
1330 			break;
1331 
1332 		/* Just consider the last segment and ...*/
1333 		if (likely(!(status & tx_not_ls))) {
1334 			/* ... verify the status error condition */
1335 			if (unlikely(status & tx_err)) {
1336 				priv->dev->stats.tx_errors++;
1337 			} else {
1338 				priv->dev->stats.tx_packets++;
1339 				priv->xstats.tx_pkt_n++;
1340 			}
1341 			stmmac_get_tx_hwtstamp(priv, p, skb);
1342 		}
1343 
1344 		if (likely(priv->tx_skbuff_dma[entry].buf)) {
1345 			if (priv->tx_skbuff_dma[entry].map_as_page)
1346 				dma_unmap_page(priv->device,
1347 					       priv->tx_skbuff_dma[entry].buf,
1348 					       priv->tx_skbuff_dma[entry].len,
1349 					       DMA_TO_DEVICE);
1350 			else
1351 				dma_unmap_single(priv->device,
1352 						 priv->tx_skbuff_dma[entry].buf,
1353 						 priv->tx_skbuff_dma[entry].len,
1354 						 DMA_TO_DEVICE);
1355 			priv->tx_skbuff_dma[entry].buf = 0;
1356 			priv->tx_skbuff_dma[entry].len = 0;
1357 			priv->tx_skbuff_dma[entry].map_as_page = false;
1358 		}
1359 
1360 		if (priv->hw->mode->clean_desc3)
1361 			priv->hw->mode->clean_desc3(priv, p);
1362 
1363 		priv->tx_skbuff_dma[entry].last_segment = false;
1364 		priv->tx_skbuff_dma[entry].is_jumbo = false;
1365 
1366 		if (likely(skb != NULL)) {
1367 			pkts_compl++;
1368 			bytes_compl += skb->len;
1369 			dev_consume_skb_any(skb);
1370 			priv->tx_skbuff[entry] = NULL;
1371 		}
1372 
1373 		priv->hw->desc->release_tx_desc(p, priv->mode);
1374 
1375 		entry = STMMAC_GET_ENTRY(entry, DMA_TX_SIZE);
1376 	}
1377 	priv->dirty_tx = entry;
1378 
1379 	netdev_completed_queue(priv->dev, pkts_compl, bytes_compl);
1380 
1381 	if (unlikely(netif_queue_stopped(priv->dev) &&
1382 		     stmmac_tx_avail(priv) > STMMAC_TX_THRESH)) {
1383 		netif_tx_lock(priv->dev);
1384 		if (netif_queue_stopped(priv->dev) &&
1385 		    stmmac_tx_avail(priv) > STMMAC_TX_THRESH) {
1386 			netif_dbg(priv, tx_done, priv->dev,
1387 				  "%s: restart transmit\n", __func__);
1388 			netif_wake_queue(priv->dev);
1389 		}
1390 		netif_tx_unlock(priv->dev);
1391 	}
1392 
1393 	if ((priv->eee_enabled) && (!priv->tx_path_in_lpi_mode)) {
1394 		stmmac_enable_eee_mode(priv);
1395 		mod_timer(&priv->eee_ctrl_timer, STMMAC_LPI_T(eee_timer));
1396 	}
1397 	spin_unlock(&priv->tx_lock);
1398 }
1399 
1400 static inline void stmmac_enable_dma_irq(struct stmmac_priv *priv)
1401 {
1402 	priv->hw->dma->enable_dma_irq(priv->ioaddr);
1403 }
1404 
1405 static inline void stmmac_disable_dma_irq(struct stmmac_priv *priv)
1406 {
1407 	priv->hw->dma->disable_dma_irq(priv->ioaddr);
1408 }
1409 
1410 /**
1411  * stmmac_tx_err - to manage the tx error
1412  * @priv: driver private structure
1413  * Description: it cleans the descriptors and restarts the transmission
1414  * in case of transmission errors.
1415  */
1416 static void stmmac_tx_err(struct stmmac_priv *priv)
1417 {
1418 	int i;
1419 	netif_stop_queue(priv->dev);
1420 
1421 	priv->hw->dma->stop_tx(priv->ioaddr);
1422 	dma_free_tx_skbufs(priv);
1423 	for (i = 0; i < DMA_TX_SIZE; i++)
1424 		if (priv->extend_desc)
1425 			priv->hw->desc->init_tx_desc(&priv->dma_etx[i].basic,
1426 						     priv->mode,
1427 						     (i == DMA_TX_SIZE - 1));
1428 		else
1429 			priv->hw->desc->init_tx_desc(&priv->dma_tx[i],
1430 						     priv->mode,
1431 						     (i == DMA_TX_SIZE - 1));
1432 	priv->dirty_tx = 0;
1433 	priv->cur_tx = 0;
1434 	netdev_reset_queue(priv->dev);
1435 	priv->hw->dma->start_tx(priv->ioaddr);
1436 
1437 	priv->dev->stats.tx_errors++;
1438 	netif_wake_queue(priv->dev);
1439 }
1440 
1441 /**
1442  * stmmac_dma_interrupt - DMA ISR
1443  * @priv: driver private structure
1444  * Description: this is the DMA ISR. It is called by the main ISR.
1445  * It calls the dwmac dma routine and schedule poll method in case of some
1446  * work can be done.
1447  */
1448 static void stmmac_dma_interrupt(struct stmmac_priv *priv)
1449 {
1450 	int status;
1451 	int rxfifosz = priv->plat->rx_fifo_size;
1452 
1453 	status = priv->hw->dma->dma_interrupt(priv->ioaddr, &priv->xstats);
1454 	if (likely((status & handle_rx)) || (status & handle_tx)) {
1455 		if (likely(napi_schedule_prep(&priv->napi))) {
1456 			stmmac_disable_dma_irq(priv);
1457 			__napi_schedule(&priv->napi);
1458 		}
1459 	}
1460 	if (unlikely(status & tx_hard_error_bump_tc)) {
1461 		/* Try to bump up the dma threshold on this failure */
1462 		if (unlikely(priv->xstats.threshold != SF_DMA_MODE) &&
1463 		    (tc <= 256)) {
1464 			tc += 64;
1465 			if (priv->plat->force_thresh_dma_mode)
1466 				priv->hw->dma->dma_mode(priv->ioaddr, tc, tc,
1467 							rxfifosz);
1468 			else
1469 				priv->hw->dma->dma_mode(priv->ioaddr, tc,
1470 							SF_DMA_MODE, rxfifosz);
1471 			priv->xstats.threshold = tc;
1472 		}
1473 	} else if (unlikely(status == tx_hard_error))
1474 		stmmac_tx_err(priv);
1475 }
1476 
1477 /**
1478  * stmmac_mmc_setup: setup the Mac Management Counters (MMC)
1479  * @priv: driver private structure
1480  * Description: this masks the MMC irq, in fact, the counters are managed in SW.
1481  */
1482 static void stmmac_mmc_setup(struct stmmac_priv *priv)
1483 {
1484 	unsigned int mode = MMC_CNTRL_RESET_ON_READ | MMC_CNTRL_COUNTER_RESET |
1485 			    MMC_CNTRL_PRESET | MMC_CNTRL_FULL_HALF_PRESET;
1486 
1487 	if (priv->synopsys_id >= DWMAC_CORE_4_00) {
1488 		priv->ptpaddr = priv->ioaddr + PTP_GMAC4_OFFSET;
1489 		priv->mmcaddr = priv->ioaddr + MMC_GMAC4_OFFSET;
1490 	} else {
1491 		priv->ptpaddr = priv->ioaddr + PTP_GMAC3_X_OFFSET;
1492 		priv->mmcaddr = priv->ioaddr + MMC_GMAC3_X_OFFSET;
1493 	}
1494 
1495 	dwmac_mmc_intr_all_mask(priv->mmcaddr);
1496 
1497 	if (priv->dma_cap.rmon) {
1498 		dwmac_mmc_ctrl(priv->mmcaddr, mode);
1499 		memset(&priv->mmc, 0, sizeof(struct stmmac_counters));
1500 	} else
1501 		netdev_info(priv->dev, "No MAC Management Counters available\n");
1502 }
1503 
1504 /**
1505  * stmmac_selec_desc_mode - to select among: normal/alternate/extend descriptors
1506  * @priv: driver private structure
1507  * Description: select the Enhanced/Alternate or Normal descriptors.
1508  * In case of Enhanced/Alternate, it checks if the extended descriptors are
1509  * supported by the HW capability register.
1510  */
1511 static void stmmac_selec_desc_mode(struct stmmac_priv *priv)
1512 {
1513 	if (priv->plat->enh_desc) {
1514 		dev_info(priv->device, "Enhanced/Alternate descriptors\n");
1515 
1516 		/* GMAC older than 3.50 has no extended descriptors */
1517 		if (priv->synopsys_id >= DWMAC_CORE_3_50) {
1518 			dev_info(priv->device, "Enabled extended descriptors\n");
1519 			priv->extend_desc = 1;
1520 		} else
1521 			dev_warn(priv->device, "Extended descriptors not supported\n");
1522 
1523 		priv->hw->desc = &enh_desc_ops;
1524 	} else {
1525 		dev_info(priv->device, "Normal descriptors\n");
1526 		priv->hw->desc = &ndesc_ops;
1527 	}
1528 }
1529 
1530 /**
1531  * stmmac_get_hw_features - get MAC capabilities from the HW cap. register.
1532  * @priv: driver private structure
1533  * Description:
1534  *  new GMAC chip generations have a new register to indicate the
1535  *  presence of the optional feature/functions.
1536  *  This can be also used to override the value passed through the
1537  *  platform and necessary for old MAC10/100 and GMAC chips.
1538  */
1539 static int stmmac_get_hw_features(struct stmmac_priv *priv)
1540 {
1541 	u32 ret = 0;
1542 
1543 	if (priv->hw->dma->get_hw_feature) {
1544 		priv->hw->dma->get_hw_feature(priv->ioaddr,
1545 					      &priv->dma_cap);
1546 		ret = 1;
1547 	}
1548 
1549 	return ret;
1550 }
1551 
1552 /**
1553  * stmmac_check_ether_addr - check if the MAC addr is valid
1554  * @priv: driver private structure
1555  * Description:
1556  * it is to verify if the MAC address is valid, in case of failures it
1557  * generates a random MAC address
1558  */
1559 static void stmmac_check_ether_addr(struct stmmac_priv *priv)
1560 {
1561 	if (!is_valid_ether_addr(priv->dev->dev_addr)) {
1562 		priv->hw->mac->get_umac_addr(priv->hw,
1563 					     priv->dev->dev_addr, 0);
1564 		if (!is_valid_ether_addr(priv->dev->dev_addr))
1565 			eth_hw_addr_random(priv->dev);
1566 		netdev_info(priv->dev, "device MAC address %pM\n",
1567 			    priv->dev->dev_addr);
1568 	}
1569 }
1570 
1571 /**
1572  * stmmac_init_dma_engine - DMA init.
1573  * @priv: driver private structure
1574  * Description:
1575  * It inits the DMA invoking the specific MAC/GMAC callback.
1576  * Some DMA parameters can be passed from the platform;
1577  * in case of these are not passed a default is kept for the MAC or GMAC.
1578  */
1579 static int stmmac_init_dma_engine(struct stmmac_priv *priv)
1580 {
1581 	int pbl = DEFAULT_DMA_PBL, fixed_burst = 0, aal = 0;
1582 	int mixed_burst = 0;
1583 	int atds = 0;
1584 	int ret = 0;
1585 
1586 	if (priv->plat->dma_cfg) {
1587 		pbl = priv->plat->dma_cfg->pbl;
1588 		fixed_burst = priv->plat->dma_cfg->fixed_burst;
1589 		mixed_burst = priv->plat->dma_cfg->mixed_burst;
1590 		aal = priv->plat->dma_cfg->aal;
1591 	}
1592 
1593 	if (priv->extend_desc && (priv->mode == STMMAC_RING_MODE))
1594 		atds = 1;
1595 
1596 	ret = priv->hw->dma->reset(priv->ioaddr);
1597 	if (ret) {
1598 		dev_err(priv->device, "Failed to reset the dma\n");
1599 		return ret;
1600 	}
1601 
1602 	priv->hw->dma->init(priv->ioaddr, pbl, fixed_burst, mixed_burst,
1603 			    aal, priv->dma_tx_phy, priv->dma_rx_phy, atds);
1604 
1605 	if (priv->synopsys_id >= DWMAC_CORE_4_00) {
1606 		priv->rx_tail_addr = priv->dma_rx_phy +
1607 			    (DMA_RX_SIZE * sizeof(struct dma_desc));
1608 		priv->hw->dma->set_rx_tail_ptr(priv->ioaddr, priv->rx_tail_addr,
1609 					       STMMAC_CHAN0);
1610 
1611 		priv->tx_tail_addr = priv->dma_tx_phy +
1612 			    (DMA_TX_SIZE * sizeof(struct dma_desc));
1613 		priv->hw->dma->set_tx_tail_ptr(priv->ioaddr, priv->tx_tail_addr,
1614 					       STMMAC_CHAN0);
1615 	}
1616 
1617 	if (priv->plat->axi && priv->hw->dma->axi)
1618 		priv->hw->dma->axi(priv->ioaddr, priv->plat->axi);
1619 
1620 	return ret;
1621 }
1622 
1623 /**
1624  * stmmac_tx_timer - mitigation sw timer for tx.
1625  * @data: data pointer
1626  * Description:
1627  * This is the timer handler to directly invoke the stmmac_tx_clean.
1628  */
1629 static void stmmac_tx_timer(unsigned long data)
1630 {
1631 	struct stmmac_priv *priv = (struct stmmac_priv *)data;
1632 
1633 	stmmac_tx_clean(priv);
1634 }
1635 
1636 /**
1637  * stmmac_init_tx_coalesce - init tx mitigation options.
1638  * @priv: driver private structure
1639  * Description:
1640  * This inits the transmit coalesce parameters: i.e. timer rate,
1641  * timer handler and default threshold used for enabling the
1642  * interrupt on completion bit.
1643  */
1644 static void stmmac_init_tx_coalesce(struct stmmac_priv *priv)
1645 {
1646 	priv->tx_coal_frames = STMMAC_TX_FRAMES;
1647 	priv->tx_coal_timer = STMMAC_COAL_TX_TIMER;
1648 	init_timer(&priv->txtimer);
1649 	priv->txtimer.expires = STMMAC_COAL_TIMER(priv->tx_coal_timer);
1650 	priv->txtimer.data = (unsigned long)priv;
1651 	priv->txtimer.function = stmmac_tx_timer;
1652 	add_timer(&priv->txtimer);
1653 }
1654 
1655 /**
1656  * stmmac_hw_setup - setup mac in a usable state.
1657  *  @dev : pointer to the device structure.
1658  *  Description:
1659  *  this is the main function to setup the HW in a usable state because the
1660  *  dma engine is reset, the core registers are configured (e.g. AXI,
1661  *  Checksum features, timers). The DMA is ready to start receiving and
1662  *  transmitting.
1663  *  Return value:
1664  *  0 on success and an appropriate (-)ve integer as defined in errno.h
1665  *  file on failure.
1666  */
1667 static int stmmac_hw_setup(struct net_device *dev, bool init_ptp)
1668 {
1669 	struct stmmac_priv *priv = netdev_priv(dev);
1670 	int ret;
1671 
1672 	/* DMA initialization and SW reset */
1673 	ret = stmmac_init_dma_engine(priv);
1674 	if (ret < 0) {
1675 		netdev_err(priv->dev, "%s: DMA engine initialization failed\n",
1676 			   __func__);
1677 		return ret;
1678 	}
1679 
1680 	/* Copy the MAC addr into the HW  */
1681 	priv->hw->mac->set_umac_addr(priv->hw, dev->dev_addr, 0);
1682 
1683 	/* If required, perform hw setup of the bus. */
1684 	if (priv->plat->bus_setup)
1685 		priv->plat->bus_setup(priv->ioaddr);
1686 
1687 	/* PS and related bits will be programmed according to the speed */
1688 	if (priv->hw->pcs) {
1689 		int speed = priv->plat->mac_port_sel_speed;
1690 
1691 		if ((speed == SPEED_10) || (speed == SPEED_100) ||
1692 		    (speed == SPEED_1000)) {
1693 			priv->hw->ps = speed;
1694 		} else {
1695 			dev_warn(priv->device, "invalid port speed\n");
1696 			priv->hw->ps = 0;
1697 		}
1698 	}
1699 
1700 	/* Initialize the MAC Core */
1701 	priv->hw->mac->core_init(priv->hw, dev->mtu);
1702 
1703 	ret = priv->hw->mac->rx_ipc(priv->hw);
1704 	if (!ret) {
1705 		netdev_warn(priv->dev, "RX IPC Checksum Offload disabled\n");
1706 		priv->plat->rx_coe = STMMAC_RX_COE_NONE;
1707 		priv->hw->rx_csum = 0;
1708 	}
1709 
1710 	/* Enable the MAC Rx/Tx */
1711 	if (priv->synopsys_id >= DWMAC_CORE_4_00)
1712 		stmmac_dwmac4_set_mac(priv->ioaddr, true);
1713 	else
1714 		stmmac_set_mac(priv->ioaddr, true);
1715 
1716 	/* Set the HW DMA mode and the COE */
1717 	stmmac_dma_operation_mode(priv);
1718 
1719 	stmmac_mmc_setup(priv);
1720 
1721 	if (init_ptp) {
1722 		ret = stmmac_init_ptp(priv);
1723 		if (ret)
1724 			netdev_warn(priv->dev, "fail to init PTP.\n");
1725 	}
1726 
1727 #ifdef CONFIG_DEBUG_FS
1728 	ret = stmmac_init_fs(dev);
1729 	if (ret < 0)
1730 		netdev_warn(priv->dev, "%s: failed debugFS registration\n",
1731 			    __func__);
1732 #endif
1733 	/* Start the ball rolling... */
1734 	netdev_dbg(priv->dev, "DMA RX/TX processes started...\n");
1735 	priv->hw->dma->start_tx(priv->ioaddr);
1736 	priv->hw->dma->start_rx(priv->ioaddr);
1737 
1738 	/* Dump DMA/MAC registers */
1739 	if (netif_msg_hw(priv)) {
1740 		priv->hw->mac->dump_regs(priv->hw);
1741 		priv->hw->dma->dump_regs(priv->ioaddr);
1742 	}
1743 	priv->tx_lpi_timer = STMMAC_DEFAULT_TWT_LS;
1744 
1745 	if ((priv->use_riwt) && (priv->hw->dma->rx_watchdog)) {
1746 		priv->rx_riwt = MAX_DMA_RIWT;
1747 		priv->hw->dma->rx_watchdog(priv->ioaddr, MAX_DMA_RIWT);
1748 	}
1749 
1750 	if (priv->hw->pcs && priv->hw->mac->pcs_ctrl_ane)
1751 		priv->hw->mac->pcs_ctrl_ane(priv->hw, 1, priv->hw->ps, 0);
1752 
1753 	/*  set TX ring length */
1754 	if (priv->hw->dma->set_tx_ring_len)
1755 		priv->hw->dma->set_tx_ring_len(priv->ioaddr,
1756 					       (DMA_TX_SIZE - 1));
1757 	/*  set RX ring length */
1758 	if (priv->hw->dma->set_rx_ring_len)
1759 		priv->hw->dma->set_rx_ring_len(priv->ioaddr,
1760 					       (DMA_RX_SIZE - 1));
1761 	/* Enable TSO */
1762 	if (priv->tso)
1763 		priv->hw->dma->enable_tso(priv->ioaddr, 1, STMMAC_CHAN0);
1764 
1765 	return 0;
1766 }
1767 
1768 /**
1769  *  stmmac_open - open entry point of the driver
1770  *  @dev : pointer to the device structure.
1771  *  Description:
1772  *  This function is the open entry point of the driver.
1773  *  Return value:
1774  *  0 on success and an appropriate (-)ve integer as defined in errno.h
1775  *  file on failure.
1776  */
1777 static int stmmac_open(struct net_device *dev)
1778 {
1779 	struct stmmac_priv *priv = netdev_priv(dev);
1780 	int ret;
1781 
1782 	stmmac_check_ether_addr(priv);
1783 
1784 	if (priv->hw->pcs != STMMAC_PCS_RGMII &&
1785 	    priv->hw->pcs != STMMAC_PCS_TBI &&
1786 	    priv->hw->pcs != STMMAC_PCS_RTBI) {
1787 		ret = stmmac_init_phy(dev);
1788 		if (ret) {
1789 			netdev_err(priv->dev,
1790 				   "%s: Cannot attach to PHY (error: %d)\n",
1791 				   __func__, ret);
1792 			return ret;
1793 		}
1794 	}
1795 
1796 	/* Extra statistics */
1797 	memset(&priv->xstats, 0, sizeof(struct stmmac_extra_stats));
1798 	priv->xstats.threshold = tc;
1799 
1800 	priv->dma_buf_sz = STMMAC_ALIGN(buf_sz);
1801 	priv->rx_copybreak = STMMAC_RX_COPYBREAK;
1802 
1803 	ret = alloc_dma_desc_resources(priv);
1804 	if (ret < 0) {
1805 		netdev_err(priv->dev, "%s: DMA descriptors allocation failed\n",
1806 			   __func__);
1807 		goto dma_desc_error;
1808 	}
1809 
1810 	ret = init_dma_desc_rings(dev, GFP_KERNEL);
1811 	if (ret < 0) {
1812 		netdev_err(priv->dev, "%s: DMA descriptors initialization failed\n",
1813 			   __func__);
1814 		goto init_error;
1815 	}
1816 
1817 	ret = stmmac_hw_setup(dev, true);
1818 	if (ret < 0) {
1819 		netdev_err(priv->dev, "%s: Hw setup failed\n", __func__);
1820 		goto init_error;
1821 	}
1822 
1823 	stmmac_init_tx_coalesce(priv);
1824 
1825 	if (dev->phydev)
1826 		phy_start(dev->phydev);
1827 
1828 	/* Request the IRQ lines */
1829 	ret = request_irq(dev->irq, stmmac_interrupt,
1830 			  IRQF_SHARED, dev->name, dev);
1831 	if (unlikely(ret < 0)) {
1832 		netdev_err(priv->dev,
1833 			   "%s: ERROR: allocating the IRQ %d (error: %d)\n",
1834 			   __func__, dev->irq, ret);
1835 		goto init_error;
1836 	}
1837 
1838 	/* Request the Wake IRQ in case of another line is used for WoL */
1839 	if (priv->wol_irq != dev->irq) {
1840 		ret = request_irq(priv->wol_irq, stmmac_interrupt,
1841 				  IRQF_SHARED, dev->name, dev);
1842 		if (unlikely(ret < 0)) {
1843 			netdev_err(priv->dev,
1844 				   "%s: ERROR: allocating the WoL IRQ %d (%d)\n",
1845 				   __func__, priv->wol_irq, ret);
1846 			goto wolirq_error;
1847 		}
1848 	}
1849 
1850 	/* Request the IRQ lines */
1851 	if (priv->lpi_irq > 0) {
1852 		ret = request_irq(priv->lpi_irq, stmmac_interrupt, IRQF_SHARED,
1853 				  dev->name, dev);
1854 		if (unlikely(ret < 0)) {
1855 			netdev_err(priv->dev,
1856 				   "%s: ERROR: allocating the LPI IRQ %d (%d)\n",
1857 				   __func__, priv->lpi_irq, ret);
1858 			goto lpiirq_error;
1859 		}
1860 	}
1861 
1862 	napi_enable(&priv->napi);
1863 	netif_start_queue(dev);
1864 
1865 	return 0;
1866 
1867 lpiirq_error:
1868 	if (priv->wol_irq != dev->irq)
1869 		free_irq(priv->wol_irq, dev);
1870 wolirq_error:
1871 	free_irq(dev->irq, dev);
1872 
1873 init_error:
1874 	free_dma_desc_resources(priv);
1875 dma_desc_error:
1876 	if (dev->phydev)
1877 		phy_disconnect(dev->phydev);
1878 
1879 	return ret;
1880 }
1881 
1882 /**
1883  *  stmmac_release - close entry point of the driver
1884  *  @dev : device pointer.
1885  *  Description:
1886  *  This is the stop entry point of the driver.
1887  */
1888 static int stmmac_release(struct net_device *dev)
1889 {
1890 	struct stmmac_priv *priv = netdev_priv(dev);
1891 
1892 	if (priv->eee_enabled)
1893 		del_timer_sync(&priv->eee_ctrl_timer);
1894 
1895 	/* Stop and disconnect the PHY */
1896 	if (dev->phydev) {
1897 		phy_stop(dev->phydev);
1898 		phy_disconnect(dev->phydev);
1899 	}
1900 
1901 	netif_stop_queue(dev);
1902 
1903 	napi_disable(&priv->napi);
1904 
1905 	del_timer_sync(&priv->txtimer);
1906 
1907 	/* Free the IRQ lines */
1908 	free_irq(dev->irq, dev);
1909 	if (priv->wol_irq != dev->irq)
1910 		free_irq(priv->wol_irq, dev);
1911 	if (priv->lpi_irq > 0)
1912 		free_irq(priv->lpi_irq, dev);
1913 
1914 	/* Stop TX/RX DMA and clear the descriptors */
1915 	priv->hw->dma->stop_tx(priv->ioaddr);
1916 	priv->hw->dma->stop_rx(priv->ioaddr);
1917 
1918 	/* Release and free the Rx/Tx resources */
1919 	free_dma_desc_resources(priv);
1920 
1921 	/* Disable the MAC Rx/Tx */
1922 	stmmac_set_mac(priv->ioaddr, false);
1923 
1924 	netif_carrier_off(dev);
1925 
1926 #ifdef CONFIG_DEBUG_FS
1927 	stmmac_exit_fs(dev);
1928 #endif
1929 
1930 	stmmac_release_ptp(priv);
1931 
1932 	return 0;
1933 }
1934 
1935 /**
1936  *  stmmac_tso_allocator - close entry point of the driver
1937  *  @priv: driver private structure
1938  *  @des: buffer start address
1939  *  @total_len: total length to fill in descriptors
1940  *  @last_segmant: condition for the last descriptor
1941  *  Description:
1942  *  This function fills descriptor and request new descriptors according to
1943  *  buffer length to fill
1944  */
1945 static void stmmac_tso_allocator(struct stmmac_priv *priv, unsigned int des,
1946 				 int total_len, bool last_segment)
1947 {
1948 	struct dma_desc *desc;
1949 	int tmp_len;
1950 	u32 buff_size;
1951 
1952 	tmp_len = total_len;
1953 
1954 	while (tmp_len > 0) {
1955 		priv->cur_tx = STMMAC_GET_ENTRY(priv->cur_tx, DMA_TX_SIZE);
1956 		desc = priv->dma_tx + priv->cur_tx;
1957 
1958 		desc->des0 = cpu_to_le32(des + (total_len - tmp_len));
1959 		buff_size = tmp_len >= TSO_MAX_BUFF_SIZE ?
1960 			    TSO_MAX_BUFF_SIZE : tmp_len;
1961 
1962 		priv->hw->desc->prepare_tso_tx_desc(desc, 0, buff_size,
1963 			0, 1,
1964 			(last_segment) && (buff_size < TSO_MAX_BUFF_SIZE),
1965 			0, 0);
1966 
1967 		tmp_len -= TSO_MAX_BUFF_SIZE;
1968 	}
1969 }
1970 
1971 /**
1972  *  stmmac_tso_xmit - Tx entry point of the driver for oversized frames (TSO)
1973  *  @skb : the socket buffer
1974  *  @dev : device pointer
1975  *  Description: this is the transmit function that is called on TSO frames
1976  *  (support available on GMAC4 and newer chips).
1977  *  Diagram below show the ring programming in case of TSO frames:
1978  *
1979  *  First Descriptor
1980  *   --------
1981  *   | DES0 |---> buffer1 = L2/L3/L4 header
1982  *   | DES1 |---> TCP Payload (can continue on next descr...)
1983  *   | DES2 |---> buffer 1 and 2 len
1984  *   | DES3 |---> must set TSE, TCP hdr len-> [22:19]. TCP payload len [17:0]
1985  *   --------
1986  *	|
1987  *     ...
1988  *	|
1989  *   --------
1990  *   | DES0 | --| Split TCP Payload on Buffers 1 and 2
1991  *   | DES1 | --|
1992  *   | DES2 | --> buffer 1 and 2 len
1993  *   | DES3 |
1994  *   --------
1995  *
1996  * mss is fixed when enable tso, so w/o programming the TDES3 ctx field.
1997  */
1998 static netdev_tx_t stmmac_tso_xmit(struct sk_buff *skb, struct net_device *dev)
1999 {
2000 	u32 pay_len, mss;
2001 	int tmp_pay_len = 0;
2002 	struct stmmac_priv *priv = netdev_priv(dev);
2003 	int nfrags = skb_shinfo(skb)->nr_frags;
2004 	unsigned int first_entry, des;
2005 	struct dma_desc *desc, *first, *mss_desc = NULL;
2006 	u8 proto_hdr_len;
2007 	int i;
2008 
2009 	spin_lock(&priv->tx_lock);
2010 
2011 	/* Compute header lengths */
2012 	proto_hdr_len = skb_transport_offset(skb) + tcp_hdrlen(skb);
2013 
2014 	/* Desc availability based on threshold should be enough safe */
2015 	if (unlikely(stmmac_tx_avail(priv) <
2016 		(((skb->len - proto_hdr_len) / TSO_MAX_BUFF_SIZE + 1)))) {
2017 		if (!netif_queue_stopped(dev)) {
2018 			netif_stop_queue(dev);
2019 			/* This is a hard error, log it. */
2020 			netdev_err(priv->dev,
2021 				   "%s: Tx Ring full when queue awake\n",
2022 				   __func__);
2023 		}
2024 		spin_unlock(&priv->tx_lock);
2025 		return NETDEV_TX_BUSY;
2026 	}
2027 
2028 	pay_len = skb_headlen(skb) - proto_hdr_len; /* no frags */
2029 
2030 	mss = skb_shinfo(skb)->gso_size;
2031 
2032 	/* set new MSS value if needed */
2033 	if (mss != priv->mss) {
2034 		mss_desc = priv->dma_tx + priv->cur_tx;
2035 		priv->hw->desc->set_mss(mss_desc, mss);
2036 		priv->mss = mss;
2037 		priv->cur_tx = STMMAC_GET_ENTRY(priv->cur_tx, DMA_TX_SIZE);
2038 	}
2039 
2040 	if (netif_msg_tx_queued(priv)) {
2041 		pr_info("%s: tcphdrlen %d, hdr_len %d, pay_len %d, mss %d\n",
2042 			__func__, tcp_hdrlen(skb), proto_hdr_len, pay_len, mss);
2043 		pr_info("\tskb->len %d, skb->data_len %d\n", skb->len,
2044 			skb->data_len);
2045 	}
2046 
2047 	first_entry = priv->cur_tx;
2048 
2049 	desc = priv->dma_tx + first_entry;
2050 	first = desc;
2051 
2052 	/* first descriptor: fill Headers on Buf1 */
2053 	des = dma_map_single(priv->device, skb->data, skb_headlen(skb),
2054 			     DMA_TO_DEVICE);
2055 	if (dma_mapping_error(priv->device, des))
2056 		goto dma_map_err;
2057 
2058 	priv->tx_skbuff_dma[first_entry].buf = des;
2059 	priv->tx_skbuff_dma[first_entry].len = skb_headlen(skb);
2060 	priv->tx_skbuff[first_entry] = skb;
2061 
2062 	first->des0 = cpu_to_le32(des);
2063 
2064 	/* Fill start of payload in buff2 of first descriptor */
2065 	if (pay_len)
2066 		first->des1 = cpu_to_le32(des + proto_hdr_len);
2067 
2068 	/* If needed take extra descriptors to fill the remaining payload */
2069 	tmp_pay_len = pay_len - TSO_MAX_BUFF_SIZE;
2070 
2071 	stmmac_tso_allocator(priv, des, tmp_pay_len, (nfrags == 0));
2072 
2073 	/* Prepare fragments */
2074 	for (i = 0; i < nfrags; i++) {
2075 		const skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
2076 
2077 		des = skb_frag_dma_map(priv->device, frag, 0,
2078 				       skb_frag_size(frag),
2079 				       DMA_TO_DEVICE);
2080 
2081 		stmmac_tso_allocator(priv, des, skb_frag_size(frag),
2082 				     (i == nfrags - 1));
2083 
2084 		priv->tx_skbuff_dma[priv->cur_tx].buf = des;
2085 		priv->tx_skbuff_dma[priv->cur_tx].len = skb_frag_size(frag);
2086 		priv->tx_skbuff[priv->cur_tx] = NULL;
2087 		priv->tx_skbuff_dma[priv->cur_tx].map_as_page = true;
2088 	}
2089 
2090 	priv->tx_skbuff_dma[priv->cur_tx].last_segment = true;
2091 
2092 	priv->cur_tx = STMMAC_GET_ENTRY(priv->cur_tx, DMA_TX_SIZE);
2093 
2094 	if (unlikely(stmmac_tx_avail(priv) <= (MAX_SKB_FRAGS + 1))) {
2095 		netif_dbg(priv, hw, priv->dev, "%s: stop transmitted packets\n",
2096 			  __func__);
2097 		netif_stop_queue(dev);
2098 	}
2099 
2100 	dev->stats.tx_bytes += skb->len;
2101 	priv->xstats.tx_tso_frames++;
2102 	priv->xstats.tx_tso_nfrags += nfrags;
2103 
2104 	/* Manage tx mitigation */
2105 	priv->tx_count_frames += nfrags + 1;
2106 	if (likely(priv->tx_coal_frames > priv->tx_count_frames)) {
2107 		mod_timer(&priv->txtimer,
2108 			  STMMAC_COAL_TIMER(priv->tx_coal_timer));
2109 	} else {
2110 		priv->tx_count_frames = 0;
2111 		priv->hw->desc->set_tx_ic(desc);
2112 		priv->xstats.tx_set_ic_bit++;
2113 	}
2114 
2115 	if (!priv->hwts_tx_en)
2116 		skb_tx_timestamp(skb);
2117 
2118 	if (unlikely((skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP) &&
2119 		     priv->hwts_tx_en)) {
2120 		/* declare that device is doing timestamping */
2121 		skb_shinfo(skb)->tx_flags |= SKBTX_IN_PROGRESS;
2122 		priv->hw->desc->enable_tx_timestamp(first);
2123 	}
2124 
2125 	/* Complete the first descriptor before granting the DMA */
2126 	priv->hw->desc->prepare_tso_tx_desc(first, 1,
2127 			proto_hdr_len,
2128 			pay_len,
2129 			1, priv->tx_skbuff_dma[first_entry].last_segment,
2130 			tcp_hdrlen(skb) / 4, (skb->len - proto_hdr_len));
2131 
2132 	/* If context desc is used to change MSS */
2133 	if (mss_desc)
2134 		priv->hw->desc->set_tx_owner(mss_desc);
2135 
2136 	/* The own bit must be the latest setting done when prepare the
2137 	 * descriptor and then barrier is needed to make sure that
2138 	 * all is coherent before granting the DMA engine.
2139 	 */
2140 	smp_wmb();
2141 
2142 	if (netif_msg_pktdata(priv)) {
2143 		pr_info("%s: curr=%d dirty=%d f=%d, e=%d, f_p=%p, nfrags %d\n",
2144 			__func__, priv->cur_tx, priv->dirty_tx, first_entry,
2145 			priv->cur_tx, first, nfrags);
2146 
2147 		priv->hw->desc->display_ring((void *)priv->dma_tx, DMA_TX_SIZE,
2148 					     0);
2149 
2150 		pr_info(">>> frame to be transmitted: ");
2151 		print_pkt(skb->data, skb_headlen(skb));
2152 	}
2153 
2154 	netdev_sent_queue(dev, skb->len);
2155 
2156 	priv->hw->dma->set_tx_tail_ptr(priv->ioaddr, priv->tx_tail_addr,
2157 				       STMMAC_CHAN0);
2158 
2159 	spin_unlock(&priv->tx_lock);
2160 	return NETDEV_TX_OK;
2161 
2162 dma_map_err:
2163 	spin_unlock(&priv->tx_lock);
2164 	dev_err(priv->device, "Tx dma map failed\n");
2165 	dev_kfree_skb(skb);
2166 	priv->dev->stats.tx_dropped++;
2167 	return NETDEV_TX_OK;
2168 }
2169 
2170 /**
2171  *  stmmac_xmit - Tx entry point of the driver
2172  *  @skb : the socket buffer
2173  *  @dev : device pointer
2174  *  Description : this is the tx entry point of the driver.
2175  *  It programs the chain or the ring and supports oversized frames
2176  *  and SG feature.
2177  */
2178 static netdev_tx_t stmmac_xmit(struct sk_buff *skb, struct net_device *dev)
2179 {
2180 	struct stmmac_priv *priv = netdev_priv(dev);
2181 	unsigned int nopaged_len = skb_headlen(skb);
2182 	int i, csum_insertion = 0, is_jumbo = 0;
2183 	int nfrags = skb_shinfo(skb)->nr_frags;
2184 	unsigned int entry, first_entry;
2185 	struct dma_desc *desc, *first;
2186 	unsigned int enh_desc;
2187 	unsigned int des;
2188 
2189 	/* Manage oversized TCP frames for GMAC4 device */
2190 	if (skb_is_gso(skb) && priv->tso) {
2191 		if (ip_hdr(skb)->protocol == IPPROTO_TCP)
2192 			return stmmac_tso_xmit(skb, dev);
2193 	}
2194 
2195 	spin_lock(&priv->tx_lock);
2196 
2197 	if (unlikely(stmmac_tx_avail(priv) < nfrags + 1)) {
2198 		spin_unlock(&priv->tx_lock);
2199 		if (!netif_queue_stopped(dev)) {
2200 			netif_stop_queue(dev);
2201 			/* This is a hard error, log it. */
2202 			netdev_err(priv->dev,
2203 				   "%s: Tx Ring full when queue awake\n",
2204 				   __func__);
2205 		}
2206 		return NETDEV_TX_BUSY;
2207 	}
2208 
2209 	if (priv->tx_path_in_lpi_mode)
2210 		stmmac_disable_eee_mode(priv);
2211 
2212 	entry = priv->cur_tx;
2213 	first_entry = entry;
2214 
2215 	csum_insertion = (skb->ip_summed == CHECKSUM_PARTIAL);
2216 
2217 	if (likely(priv->extend_desc))
2218 		desc = (struct dma_desc *)(priv->dma_etx + entry);
2219 	else
2220 		desc = priv->dma_tx + entry;
2221 
2222 	first = desc;
2223 
2224 	priv->tx_skbuff[first_entry] = skb;
2225 
2226 	enh_desc = priv->plat->enh_desc;
2227 	/* To program the descriptors according to the size of the frame */
2228 	if (enh_desc)
2229 		is_jumbo = priv->hw->mode->is_jumbo_frm(skb->len, enh_desc);
2230 
2231 	if (unlikely(is_jumbo) && likely(priv->synopsys_id <
2232 					 DWMAC_CORE_4_00)) {
2233 		entry = priv->hw->mode->jumbo_frm(priv, skb, csum_insertion);
2234 		if (unlikely(entry < 0))
2235 			goto dma_map_err;
2236 	}
2237 
2238 	for (i = 0; i < nfrags; i++) {
2239 		const skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
2240 		int len = skb_frag_size(frag);
2241 		bool last_segment = (i == (nfrags - 1));
2242 
2243 		entry = STMMAC_GET_ENTRY(entry, DMA_TX_SIZE);
2244 
2245 		if (likely(priv->extend_desc))
2246 			desc = (struct dma_desc *)(priv->dma_etx + entry);
2247 		else
2248 			desc = priv->dma_tx + entry;
2249 
2250 		des = skb_frag_dma_map(priv->device, frag, 0, len,
2251 				       DMA_TO_DEVICE);
2252 		if (dma_mapping_error(priv->device, des))
2253 			goto dma_map_err; /* should reuse desc w/o issues */
2254 
2255 		priv->tx_skbuff[entry] = NULL;
2256 
2257 		priv->tx_skbuff_dma[entry].buf = des;
2258 		if (unlikely(priv->synopsys_id >= DWMAC_CORE_4_00))
2259 			desc->des0 = cpu_to_le32(des);
2260 		else
2261 			desc->des2 = cpu_to_le32(des);
2262 
2263 		priv->tx_skbuff_dma[entry].map_as_page = true;
2264 		priv->tx_skbuff_dma[entry].len = len;
2265 		priv->tx_skbuff_dma[entry].last_segment = last_segment;
2266 
2267 		/* Prepare the descriptor and set the own bit too */
2268 		priv->hw->desc->prepare_tx_desc(desc, 0, len, csum_insertion,
2269 						priv->mode, 1, last_segment);
2270 	}
2271 
2272 	entry = STMMAC_GET_ENTRY(entry, DMA_TX_SIZE);
2273 
2274 	priv->cur_tx = entry;
2275 
2276 	if (netif_msg_pktdata(priv)) {
2277 		void *tx_head;
2278 
2279 		netdev_dbg(priv->dev,
2280 			   "%s: curr=%d dirty=%d f=%d, e=%d, first=%p, nfrags=%d",
2281 			   __func__, priv->cur_tx, priv->dirty_tx, first_entry,
2282 			   entry, first, nfrags);
2283 
2284 		if (priv->extend_desc)
2285 			tx_head = (void *)priv->dma_etx;
2286 		else
2287 			tx_head = (void *)priv->dma_tx;
2288 
2289 		priv->hw->desc->display_ring(tx_head, DMA_TX_SIZE, false);
2290 
2291 		netdev_dbg(priv->dev, ">>> frame to be transmitted: ");
2292 		print_pkt(skb->data, skb->len);
2293 	}
2294 
2295 	if (unlikely(stmmac_tx_avail(priv) <= (MAX_SKB_FRAGS + 1))) {
2296 		netif_dbg(priv, hw, priv->dev, "%s: stop transmitted packets\n",
2297 			  __func__);
2298 		netif_stop_queue(dev);
2299 	}
2300 
2301 	dev->stats.tx_bytes += skb->len;
2302 
2303 	/* According to the coalesce parameter the IC bit for the latest
2304 	 * segment is reset and the timer re-started to clean the tx status.
2305 	 * This approach takes care about the fragments: desc is the first
2306 	 * element in case of no SG.
2307 	 */
2308 	priv->tx_count_frames += nfrags + 1;
2309 	if (likely(priv->tx_coal_frames > priv->tx_count_frames)) {
2310 		mod_timer(&priv->txtimer,
2311 			  STMMAC_COAL_TIMER(priv->tx_coal_timer));
2312 	} else {
2313 		priv->tx_count_frames = 0;
2314 		priv->hw->desc->set_tx_ic(desc);
2315 		priv->xstats.tx_set_ic_bit++;
2316 	}
2317 
2318 	if (!priv->hwts_tx_en)
2319 		skb_tx_timestamp(skb);
2320 
2321 	/* Ready to fill the first descriptor and set the OWN bit w/o any
2322 	 * problems because all the descriptors are actually ready to be
2323 	 * passed to the DMA engine.
2324 	 */
2325 	if (likely(!is_jumbo)) {
2326 		bool last_segment = (nfrags == 0);
2327 
2328 		des = dma_map_single(priv->device, skb->data,
2329 				     nopaged_len, DMA_TO_DEVICE);
2330 		if (dma_mapping_error(priv->device, des))
2331 			goto dma_map_err;
2332 
2333 		priv->tx_skbuff_dma[first_entry].buf = des;
2334 		if (unlikely(priv->synopsys_id >= DWMAC_CORE_4_00))
2335 			first->des0 = cpu_to_le32(des);
2336 		else
2337 			first->des2 = cpu_to_le32(des);
2338 
2339 		priv->tx_skbuff_dma[first_entry].len = nopaged_len;
2340 		priv->tx_skbuff_dma[first_entry].last_segment = last_segment;
2341 
2342 		if (unlikely((skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP) &&
2343 			     priv->hwts_tx_en)) {
2344 			/* declare that device is doing timestamping */
2345 			skb_shinfo(skb)->tx_flags |= SKBTX_IN_PROGRESS;
2346 			priv->hw->desc->enable_tx_timestamp(first);
2347 		}
2348 
2349 		/* Prepare the first descriptor setting the OWN bit too */
2350 		priv->hw->desc->prepare_tx_desc(first, 1, nopaged_len,
2351 						csum_insertion, priv->mode, 1,
2352 						last_segment);
2353 
2354 		/* The own bit must be the latest setting done when prepare the
2355 		 * descriptor and then barrier is needed to make sure that
2356 		 * all is coherent before granting the DMA engine.
2357 		 */
2358 		smp_wmb();
2359 	}
2360 
2361 	netdev_sent_queue(dev, skb->len);
2362 
2363 	if (priv->synopsys_id < DWMAC_CORE_4_00)
2364 		priv->hw->dma->enable_dma_transmission(priv->ioaddr);
2365 	else
2366 		priv->hw->dma->set_tx_tail_ptr(priv->ioaddr, priv->tx_tail_addr,
2367 					       STMMAC_CHAN0);
2368 
2369 	spin_unlock(&priv->tx_lock);
2370 	return NETDEV_TX_OK;
2371 
2372 dma_map_err:
2373 	spin_unlock(&priv->tx_lock);
2374 	netdev_err(priv->dev, "Tx DMA map failed\n");
2375 	dev_kfree_skb(skb);
2376 	priv->dev->stats.tx_dropped++;
2377 	return NETDEV_TX_OK;
2378 }
2379 
2380 static void stmmac_rx_vlan(struct net_device *dev, struct sk_buff *skb)
2381 {
2382 	struct ethhdr *ehdr;
2383 	u16 vlanid;
2384 
2385 	if ((dev->features & NETIF_F_HW_VLAN_CTAG_RX) ==
2386 	    NETIF_F_HW_VLAN_CTAG_RX &&
2387 	    !__vlan_get_tag(skb, &vlanid)) {
2388 		/* pop the vlan tag */
2389 		ehdr = (struct ethhdr *)skb->data;
2390 		memmove(skb->data + VLAN_HLEN, ehdr, ETH_ALEN * 2);
2391 		skb_pull(skb, VLAN_HLEN);
2392 		__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), vlanid);
2393 	}
2394 }
2395 
2396 
2397 static inline int stmmac_rx_threshold_count(struct stmmac_priv *priv)
2398 {
2399 	if (priv->rx_zeroc_thresh < STMMAC_RX_THRESH)
2400 		return 0;
2401 
2402 	return 1;
2403 }
2404 
2405 /**
2406  * stmmac_rx_refill - refill used skb preallocated buffers
2407  * @priv: driver private structure
2408  * Description : this is to reallocate the skb for the reception process
2409  * that is based on zero-copy.
2410  */
2411 static inline void stmmac_rx_refill(struct stmmac_priv *priv)
2412 {
2413 	int bfsize = priv->dma_buf_sz;
2414 	unsigned int entry = priv->dirty_rx;
2415 	int dirty = stmmac_rx_dirty(priv);
2416 
2417 	while (dirty-- > 0) {
2418 		struct dma_desc *p;
2419 
2420 		if (priv->extend_desc)
2421 			p = (struct dma_desc *)(priv->dma_erx + entry);
2422 		else
2423 			p = priv->dma_rx + entry;
2424 
2425 		if (likely(priv->rx_skbuff[entry] == NULL)) {
2426 			struct sk_buff *skb;
2427 
2428 			skb = netdev_alloc_skb_ip_align(priv->dev, bfsize);
2429 			if (unlikely(!skb)) {
2430 				/* so for a while no zero-copy! */
2431 				priv->rx_zeroc_thresh = STMMAC_RX_THRESH;
2432 				if (unlikely(net_ratelimit()))
2433 					dev_err(priv->device,
2434 						"fail to alloc skb entry %d\n",
2435 						entry);
2436 				break;
2437 			}
2438 
2439 			priv->rx_skbuff[entry] = skb;
2440 			priv->rx_skbuff_dma[entry] =
2441 			    dma_map_single(priv->device, skb->data, bfsize,
2442 					   DMA_FROM_DEVICE);
2443 			if (dma_mapping_error(priv->device,
2444 					      priv->rx_skbuff_dma[entry])) {
2445 				netdev_err(priv->dev, "Rx DMA map failed\n");
2446 				dev_kfree_skb(skb);
2447 				break;
2448 			}
2449 
2450 			if (unlikely(priv->synopsys_id >= DWMAC_CORE_4_00)) {
2451 				p->des0 = cpu_to_le32(priv->rx_skbuff_dma[entry]);
2452 				p->des1 = 0;
2453 			} else {
2454 				p->des2 = cpu_to_le32(priv->rx_skbuff_dma[entry]);
2455 			}
2456 			if (priv->hw->mode->refill_desc3)
2457 				priv->hw->mode->refill_desc3(priv, p);
2458 
2459 			if (priv->rx_zeroc_thresh > 0)
2460 				priv->rx_zeroc_thresh--;
2461 
2462 			netif_dbg(priv, rx_status, priv->dev,
2463 				  "refill entry #%d\n", entry);
2464 		}
2465 		wmb();
2466 
2467 		if (unlikely(priv->synopsys_id >= DWMAC_CORE_4_00))
2468 			priv->hw->desc->init_rx_desc(p, priv->use_riwt, 0, 0);
2469 		else
2470 			priv->hw->desc->set_rx_owner(p);
2471 
2472 		wmb();
2473 
2474 		entry = STMMAC_GET_ENTRY(entry, DMA_RX_SIZE);
2475 	}
2476 	priv->dirty_rx = entry;
2477 }
2478 
2479 /**
2480  * stmmac_rx - manage the receive process
2481  * @priv: driver private structure
2482  * @limit: napi bugget.
2483  * Description :  this the function called by the napi poll method.
2484  * It gets all the frames inside the ring.
2485  */
2486 static int stmmac_rx(struct stmmac_priv *priv, int limit)
2487 {
2488 	unsigned int entry = priv->cur_rx;
2489 	unsigned int next_entry;
2490 	unsigned int count = 0;
2491 	int coe = priv->hw->rx_csum;
2492 
2493 	if (netif_msg_rx_status(priv)) {
2494 		void *rx_head;
2495 
2496 		netdev_dbg(priv->dev, "%s: descriptor ring:\n", __func__);
2497 		if (priv->extend_desc)
2498 			rx_head = (void *)priv->dma_erx;
2499 		else
2500 			rx_head = (void *)priv->dma_rx;
2501 
2502 		priv->hw->desc->display_ring(rx_head, DMA_RX_SIZE, true);
2503 	}
2504 	while (count < limit) {
2505 		int status;
2506 		struct dma_desc *p;
2507 		struct dma_desc *np;
2508 
2509 		if (priv->extend_desc)
2510 			p = (struct dma_desc *)(priv->dma_erx + entry);
2511 		else
2512 			p = priv->dma_rx + entry;
2513 
2514 		/* read the status of the incoming frame */
2515 		status = priv->hw->desc->rx_status(&priv->dev->stats,
2516 						   &priv->xstats, p);
2517 		/* check if managed by the DMA otherwise go ahead */
2518 		if (unlikely(status & dma_own))
2519 			break;
2520 
2521 		count++;
2522 
2523 		priv->cur_rx = STMMAC_GET_ENTRY(priv->cur_rx, DMA_RX_SIZE);
2524 		next_entry = priv->cur_rx;
2525 
2526 		if (priv->extend_desc)
2527 			np = (struct dma_desc *)(priv->dma_erx + next_entry);
2528 		else
2529 			np = priv->dma_rx + next_entry;
2530 
2531 		prefetch(np);
2532 
2533 		if ((priv->extend_desc) && (priv->hw->desc->rx_extended_status))
2534 			priv->hw->desc->rx_extended_status(&priv->dev->stats,
2535 							   &priv->xstats,
2536 							   priv->dma_erx +
2537 							   entry);
2538 		if (unlikely(status == discard_frame)) {
2539 			priv->dev->stats.rx_errors++;
2540 			if (priv->hwts_rx_en && !priv->extend_desc) {
2541 				/* DESC2 & DESC3 will be overwitten by device
2542 				 * with timestamp value, hence reinitialize
2543 				 * them in stmmac_rx_refill() function so that
2544 				 * device can reuse it.
2545 				 */
2546 				priv->rx_skbuff[entry] = NULL;
2547 				dma_unmap_single(priv->device,
2548 						 priv->rx_skbuff_dma[entry],
2549 						 priv->dma_buf_sz,
2550 						 DMA_FROM_DEVICE);
2551 			}
2552 		} else {
2553 			struct sk_buff *skb;
2554 			int frame_len;
2555 			unsigned int des;
2556 
2557 			if (unlikely(priv->synopsys_id >= DWMAC_CORE_4_00))
2558 				des = le32_to_cpu(p->des0);
2559 			else
2560 				des = le32_to_cpu(p->des2);
2561 
2562 			frame_len = priv->hw->desc->get_rx_frame_len(p, coe);
2563 
2564 			/*  If frame length is greather than skb buffer size
2565 			 *  (preallocated during init) then the packet is
2566 			 *  ignored
2567 			 */
2568 			if (frame_len > priv->dma_buf_sz) {
2569 				netdev_err(priv->dev,
2570 					   "len %d larger than size (%d)\n",
2571 					   frame_len, priv->dma_buf_sz);
2572 				priv->dev->stats.rx_length_errors++;
2573 				break;
2574 			}
2575 
2576 			/* ACS is set; GMAC core strips PAD/FCS for IEEE 802.3
2577 			 * Type frames (LLC/LLC-SNAP)
2578 			 */
2579 			if (unlikely(status != llc_snap))
2580 				frame_len -= ETH_FCS_LEN;
2581 
2582 			if (netif_msg_rx_status(priv)) {
2583 				netdev_dbg(priv->dev, "\tdesc: %p [entry %d] buff=0x%x\n",
2584 					   p, entry, des);
2585 				if (frame_len > ETH_FRAME_LEN)
2586 					netdev_dbg(priv->dev, "frame size %d, COE: %d\n",
2587 						   frame_len, status);
2588 			}
2589 
2590 			/* The zero-copy is always used for all the sizes
2591 			 * in case of GMAC4 because it needs
2592 			 * to refill the used descriptors, always.
2593 			 */
2594 			if (unlikely(!priv->plat->has_gmac4 &&
2595 				     ((frame_len < priv->rx_copybreak) ||
2596 				     stmmac_rx_threshold_count(priv)))) {
2597 				skb = netdev_alloc_skb_ip_align(priv->dev,
2598 								frame_len);
2599 				if (unlikely(!skb)) {
2600 					if (net_ratelimit())
2601 						dev_warn(priv->device,
2602 							 "packet dropped\n");
2603 					priv->dev->stats.rx_dropped++;
2604 					break;
2605 				}
2606 
2607 				dma_sync_single_for_cpu(priv->device,
2608 							priv->rx_skbuff_dma
2609 							[entry], frame_len,
2610 							DMA_FROM_DEVICE);
2611 				skb_copy_to_linear_data(skb,
2612 							priv->
2613 							rx_skbuff[entry]->data,
2614 							frame_len);
2615 
2616 				skb_put(skb, frame_len);
2617 				dma_sync_single_for_device(priv->device,
2618 							   priv->rx_skbuff_dma
2619 							   [entry], frame_len,
2620 							   DMA_FROM_DEVICE);
2621 			} else {
2622 				skb = priv->rx_skbuff[entry];
2623 				if (unlikely(!skb)) {
2624 					netdev_err(priv->dev,
2625 						   "%s: Inconsistent Rx chain\n",
2626 						   priv->dev->name);
2627 					priv->dev->stats.rx_dropped++;
2628 					break;
2629 				}
2630 				prefetch(skb->data - NET_IP_ALIGN);
2631 				priv->rx_skbuff[entry] = NULL;
2632 				priv->rx_zeroc_thresh++;
2633 
2634 				skb_put(skb, frame_len);
2635 				dma_unmap_single(priv->device,
2636 						 priv->rx_skbuff_dma[entry],
2637 						 priv->dma_buf_sz,
2638 						 DMA_FROM_DEVICE);
2639 			}
2640 
2641 			if (netif_msg_pktdata(priv)) {
2642 				netdev_dbg(priv->dev, "frame received (%dbytes)",
2643 					   frame_len);
2644 				print_pkt(skb->data, frame_len);
2645 			}
2646 
2647 			stmmac_get_rx_hwtstamp(priv, p, np, skb);
2648 
2649 			stmmac_rx_vlan(priv->dev, skb);
2650 
2651 			skb->protocol = eth_type_trans(skb, priv->dev);
2652 
2653 			if (unlikely(!coe))
2654 				skb_checksum_none_assert(skb);
2655 			else
2656 				skb->ip_summed = CHECKSUM_UNNECESSARY;
2657 
2658 			napi_gro_receive(&priv->napi, skb);
2659 
2660 			priv->dev->stats.rx_packets++;
2661 			priv->dev->stats.rx_bytes += frame_len;
2662 		}
2663 		entry = next_entry;
2664 	}
2665 
2666 	stmmac_rx_refill(priv);
2667 
2668 	priv->xstats.rx_pkt_n += count;
2669 
2670 	return count;
2671 }
2672 
2673 /**
2674  *  stmmac_poll - stmmac poll method (NAPI)
2675  *  @napi : pointer to the napi structure.
2676  *  @budget : maximum number of packets that the current CPU can receive from
2677  *	      all interfaces.
2678  *  Description :
2679  *  To look at the incoming frames and clear the tx resources.
2680  */
2681 static int stmmac_poll(struct napi_struct *napi, int budget)
2682 {
2683 	struct stmmac_priv *priv = container_of(napi, struct stmmac_priv, napi);
2684 	int work_done = 0;
2685 
2686 	priv->xstats.napi_poll++;
2687 	stmmac_tx_clean(priv);
2688 
2689 	work_done = stmmac_rx(priv, budget);
2690 	if (work_done < budget) {
2691 		napi_complete(napi);
2692 		stmmac_enable_dma_irq(priv);
2693 	}
2694 	return work_done;
2695 }
2696 
2697 /**
2698  *  stmmac_tx_timeout
2699  *  @dev : Pointer to net device structure
2700  *  Description: this function is called when a packet transmission fails to
2701  *   complete within a reasonable time. The driver will mark the error in the
2702  *   netdev structure and arrange for the device to be reset to a sane state
2703  *   in order to transmit a new packet.
2704  */
2705 static void stmmac_tx_timeout(struct net_device *dev)
2706 {
2707 	struct stmmac_priv *priv = netdev_priv(dev);
2708 
2709 	/* Clear Tx resources and restart transmitting again */
2710 	stmmac_tx_err(priv);
2711 }
2712 
2713 /**
2714  *  stmmac_set_rx_mode - entry point for multicast addressing
2715  *  @dev : pointer to the device structure
2716  *  Description:
2717  *  This function is a driver entry point which gets called by the kernel
2718  *  whenever multicast addresses must be enabled/disabled.
2719  *  Return value:
2720  *  void.
2721  */
2722 static void stmmac_set_rx_mode(struct net_device *dev)
2723 {
2724 	struct stmmac_priv *priv = netdev_priv(dev);
2725 
2726 	priv->hw->mac->set_filter(priv->hw, dev);
2727 }
2728 
2729 /**
2730  *  stmmac_change_mtu - entry point to change MTU size for the device.
2731  *  @dev : device pointer.
2732  *  @new_mtu : the new MTU size for the device.
2733  *  Description: the Maximum Transfer Unit (MTU) is used by the network layer
2734  *  to drive packet transmission. Ethernet has an MTU of 1500 octets
2735  *  (ETH_DATA_LEN). This value can be changed with ifconfig.
2736  *  Return value:
2737  *  0 on success and an appropriate (-)ve integer as defined in errno.h
2738  *  file on failure.
2739  */
2740 static int stmmac_change_mtu(struct net_device *dev, int new_mtu)
2741 {
2742 	struct stmmac_priv *priv = netdev_priv(dev);
2743 
2744 	if (netif_running(dev)) {
2745 		netdev_err(priv->dev, "must be stopped to change its MTU\n");
2746 		return -EBUSY;
2747 	}
2748 
2749 	dev->mtu = new_mtu;
2750 
2751 	netdev_update_features(dev);
2752 
2753 	return 0;
2754 }
2755 
2756 static netdev_features_t stmmac_fix_features(struct net_device *dev,
2757 					     netdev_features_t features)
2758 {
2759 	struct stmmac_priv *priv = netdev_priv(dev);
2760 
2761 	if (priv->plat->rx_coe == STMMAC_RX_COE_NONE)
2762 		features &= ~NETIF_F_RXCSUM;
2763 
2764 	if (!priv->plat->tx_coe)
2765 		features &= ~NETIF_F_CSUM_MASK;
2766 
2767 	/* Some GMAC devices have a bugged Jumbo frame support that
2768 	 * needs to have the Tx COE disabled for oversized frames
2769 	 * (due to limited buffer sizes). In this case we disable
2770 	 * the TX csum insertionin the TDES and not use SF.
2771 	 */
2772 	if (priv->plat->bugged_jumbo && (dev->mtu > ETH_DATA_LEN))
2773 		features &= ~NETIF_F_CSUM_MASK;
2774 
2775 	/* Disable tso if asked by ethtool */
2776 	if ((priv->plat->tso_en) && (priv->dma_cap.tsoen)) {
2777 		if (features & NETIF_F_TSO)
2778 			priv->tso = true;
2779 		else
2780 			priv->tso = false;
2781 	}
2782 
2783 	return features;
2784 }
2785 
2786 static int stmmac_set_features(struct net_device *netdev,
2787 			       netdev_features_t features)
2788 {
2789 	struct stmmac_priv *priv = netdev_priv(netdev);
2790 
2791 	/* Keep the COE Type in case of csum is supporting */
2792 	if (features & NETIF_F_RXCSUM)
2793 		priv->hw->rx_csum = priv->plat->rx_coe;
2794 	else
2795 		priv->hw->rx_csum = 0;
2796 	/* No check needed because rx_coe has been set before and it will be
2797 	 * fixed in case of issue.
2798 	 */
2799 	priv->hw->mac->rx_ipc(priv->hw);
2800 
2801 	return 0;
2802 }
2803 
2804 /**
2805  *  stmmac_interrupt - main ISR
2806  *  @irq: interrupt number.
2807  *  @dev_id: to pass the net device pointer.
2808  *  Description: this is the main driver interrupt service routine.
2809  *  It can call:
2810  *  o DMA service routine (to manage incoming frame reception and transmission
2811  *    status)
2812  *  o Core interrupts to manage: remote wake-up, management counter, LPI
2813  *    interrupts.
2814  */
2815 static irqreturn_t stmmac_interrupt(int irq, void *dev_id)
2816 {
2817 	struct net_device *dev = (struct net_device *)dev_id;
2818 	struct stmmac_priv *priv = netdev_priv(dev);
2819 
2820 	if (priv->irq_wake)
2821 		pm_wakeup_event(priv->device, 0);
2822 
2823 	if (unlikely(!dev)) {
2824 		netdev_err(priv->dev, "%s: invalid dev pointer\n", __func__);
2825 		return IRQ_NONE;
2826 	}
2827 
2828 	/* To handle GMAC own interrupts */
2829 	if ((priv->plat->has_gmac) || (priv->plat->has_gmac4)) {
2830 		int status = priv->hw->mac->host_irq_status(priv->hw,
2831 							    &priv->xstats);
2832 		if (unlikely(status)) {
2833 			/* For LPI we need to save the tx status */
2834 			if (status & CORE_IRQ_TX_PATH_IN_LPI_MODE)
2835 				priv->tx_path_in_lpi_mode = true;
2836 			if (status & CORE_IRQ_TX_PATH_EXIT_LPI_MODE)
2837 				priv->tx_path_in_lpi_mode = false;
2838 			if (status & CORE_IRQ_MTL_RX_OVERFLOW && priv->hw->dma->set_rx_tail_ptr)
2839 				priv->hw->dma->set_rx_tail_ptr(priv->ioaddr,
2840 							priv->rx_tail_addr,
2841 							STMMAC_CHAN0);
2842 		}
2843 
2844 		/* PCS link status */
2845 		if (priv->hw->pcs) {
2846 			if (priv->xstats.pcs_link)
2847 				netif_carrier_on(dev);
2848 			else
2849 				netif_carrier_off(dev);
2850 		}
2851 	}
2852 
2853 	/* To handle DMA interrupts */
2854 	stmmac_dma_interrupt(priv);
2855 
2856 	return IRQ_HANDLED;
2857 }
2858 
2859 #ifdef CONFIG_NET_POLL_CONTROLLER
2860 /* Polling receive - used by NETCONSOLE and other diagnostic tools
2861  * to allow network I/O with interrupts disabled.
2862  */
2863 static void stmmac_poll_controller(struct net_device *dev)
2864 {
2865 	disable_irq(dev->irq);
2866 	stmmac_interrupt(dev->irq, dev);
2867 	enable_irq(dev->irq);
2868 }
2869 #endif
2870 
2871 /**
2872  *  stmmac_ioctl - Entry point for the Ioctl
2873  *  @dev: Device pointer.
2874  *  @rq: An IOCTL specefic structure, that can contain a pointer to
2875  *  a proprietary structure used to pass information to the driver.
2876  *  @cmd: IOCTL command
2877  *  Description:
2878  *  Currently it supports the phy_mii_ioctl(...) and HW time stamping.
2879  */
2880 static int stmmac_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
2881 {
2882 	int ret = -EOPNOTSUPP;
2883 
2884 	if (!netif_running(dev))
2885 		return -EINVAL;
2886 
2887 	switch (cmd) {
2888 	case SIOCGMIIPHY:
2889 	case SIOCGMIIREG:
2890 	case SIOCSMIIREG:
2891 		if (!dev->phydev)
2892 			return -EINVAL;
2893 		ret = phy_mii_ioctl(dev->phydev, rq, cmd);
2894 		break;
2895 	case SIOCSHWTSTAMP:
2896 		ret = stmmac_hwtstamp_ioctl(dev, rq);
2897 		break;
2898 	default:
2899 		break;
2900 	}
2901 
2902 	return ret;
2903 }
2904 
2905 #ifdef CONFIG_DEBUG_FS
2906 static struct dentry *stmmac_fs_dir;
2907 
2908 static void sysfs_display_ring(void *head, int size, int extend_desc,
2909 			       struct seq_file *seq)
2910 {
2911 	int i;
2912 	struct dma_extended_desc *ep = (struct dma_extended_desc *)head;
2913 	struct dma_desc *p = (struct dma_desc *)head;
2914 
2915 	for (i = 0; i < size; i++) {
2916 		u64 x;
2917 		if (extend_desc) {
2918 			x = *(u64 *) ep;
2919 			seq_printf(seq, "%d [0x%x]: 0x%x 0x%x 0x%x 0x%x\n",
2920 				   i, (unsigned int)virt_to_phys(ep),
2921 				   le32_to_cpu(ep->basic.des0),
2922 				   le32_to_cpu(ep->basic.des1),
2923 				   le32_to_cpu(ep->basic.des2),
2924 				   le32_to_cpu(ep->basic.des3));
2925 			ep++;
2926 		} else {
2927 			x = *(u64 *) p;
2928 			seq_printf(seq, "%d [0x%x]: 0x%x 0x%x 0x%x 0x%x\n",
2929 				   i, (unsigned int)virt_to_phys(ep),
2930 				   le32_to_cpu(p->des0), le32_to_cpu(p->des1),
2931 				   le32_to_cpu(p->des2), le32_to_cpu(p->des3));
2932 			p++;
2933 		}
2934 		seq_printf(seq, "\n");
2935 	}
2936 }
2937 
2938 static int stmmac_sysfs_ring_read(struct seq_file *seq, void *v)
2939 {
2940 	struct net_device *dev = seq->private;
2941 	struct stmmac_priv *priv = netdev_priv(dev);
2942 
2943 	if (priv->extend_desc) {
2944 		seq_printf(seq, "Extended RX descriptor ring:\n");
2945 		sysfs_display_ring((void *)priv->dma_erx, DMA_RX_SIZE, 1, seq);
2946 		seq_printf(seq, "Extended TX descriptor ring:\n");
2947 		sysfs_display_ring((void *)priv->dma_etx, DMA_TX_SIZE, 1, seq);
2948 	} else {
2949 		seq_printf(seq, "RX descriptor ring:\n");
2950 		sysfs_display_ring((void *)priv->dma_rx, DMA_RX_SIZE, 0, seq);
2951 		seq_printf(seq, "TX descriptor ring:\n");
2952 		sysfs_display_ring((void *)priv->dma_tx, DMA_TX_SIZE, 0, seq);
2953 	}
2954 
2955 	return 0;
2956 }
2957 
2958 static int stmmac_sysfs_ring_open(struct inode *inode, struct file *file)
2959 {
2960 	return single_open(file, stmmac_sysfs_ring_read, inode->i_private);
2961 }
2962 
2963 /* Debugfs files, should appear in /sys/kernel/debug/stmmaceth/eth0 */
2964 
2965 static const struct file_operations stmmac_rings_status_fops = {
2966 	.owner = THIS_MODULE,
2967 	.open = stmmac_sysfs_ring_open,
2968 	.read = seq_read,
2969 	.llseek = seq_lseek,
2970 	.release = single_release,
2971 };
2972 
2973 static int stmmac_sysfs_dma_cap_read(struct seq_file *seq, void *v)
2974 {
2975 	struct net_device *dev = seq->private;
2976 	struct stmmac_priv *priv = netdev_priv(dev);
2977 
2978 	if (!priv->hw_cap_support) {
2979 		seq_printf(seq, "DMA HW features not supported\n");
2980 		return 0;
2981 	}
2982 
2983 	seq_printf(seq, "==============================\n");
2984 	seq_printf(seq, "\tDMA HW features\n");
2985 	seq_printf(seq, "==============================\n");
2986 
2987 	seq_printf(seq, "\t10/100 Mbps: %s\n",
2988 		   (priv->dma_cap.mbps_10_100) ? "Y" : "N");
2989 	seq_printf(seq, "\t1000 Mbps: %s\n",
2990 		   (priv->dma_cap.mbps_1000) ? "Y" : "N");
2991 	seq_printf(seq, "\tHalf duplex: %s\n",
2992 		   (priv->dma_cap.half_duplex) ? "Y" : "N");
2993 	seq_printf(seq, "\tHash Filter: %s\n",
2994 		   (priv->dma_cap.hash_filter) ? "Y" : "N");
2995 	seq_printf(seq, "\tMultiple MAC address registers: %s\n",
2996 		   (priv->dma_cap.multi_addr) ? "Y" : "N");
2997 	seq_printf(seq, "\tPCS (TBI/SGMII/RTBI PHY interfatces): %s\n",
2998 		   (priv->dma_cap.pcs) ? "Y" : "N");
2999 	seq_printf(seq, "\tSMA (MDIO) Interface: %s\n",
3000 		   (priv->dma_cap.sma_mdio) ? "Y" : "N");
3001 	seq_printf(seq, "\tPMT Remote wake up: %s\n",
3002 		   (priv->dma_cap.pmt_remote_wake_up) ? "Y" : "N");
3003 	seq_printf(seq, "\tPMT Magic Frame: %s\n",
3004 		   (priv->dma_cap.pmt_magic_frame) ? "Y" : "N");
3005 	seq_printf(seq, "\tRMON module: %s\n",
3006 		   (priv->dma_cap.rmon) ? "Y" : "N");
3007 	seq_printf(seq, "\tIEEE 1588-2002 Time Stamp: %s\n",
3008 		   (priv->dma_cap.time_stamp) ? "Y" : "N");
3009 	seq_printf(seq, "\tIEEE 1588-2008 Advanced Time Stamp: %s\n",
3010 		   (priv->dma_cap.atime_stamp) ? "Y" : "N");
3011 	seq_printf(seq, "\t802.3az - Energy-Efficient Ethernet (EEE): %s\n",
3012 		   (priv->dma_cap.eee) ? "Y" : "N");
3013 	seq_printf(seq, "\tAV features: %s\n", (priv->dma_cap.av) ? "Y" : "N");
3014 	seq_printf(seq, "\tChecksum Offload in TX: %s\n",
3015 		   (priv->dma_cap.tx_coe) ? "Y" : "N");
3016 	if (priv->synopsys_id >= DWMAC_CORE_4_00) {
3017 		seq_printf(seq, "\tIP Checksum Offload in RX: %s\n",
3018 			   (priv->dma_cap.rx_coe) ? "Y" : "N");
3019 	} else {
3020 		seq_printf(seq, "\tIP Checksum Offload (type1) in RX: %s\n",
3021 			   (priv->dma_cap.rx_coe_type1) ? "Y" : "N");
3022 		seq_printf(seq, "\tIP Checksum Offload (type2) in RX: %s\n",
3023 			   (priv->dma_cap.rx_coe_type2) ? "Y" : "N");
3024 	}
3025 	seq_printf(seq, "\tRXFIFO > 2048bytes: %s\n",
3026 		   (priv->dma_cap.rxfifo_over_2048) ? "Y" : "N");
3027 	seq_printf(seq, "\tNumber of Additional RX channel: %d\n",
3028 		   priv->dma_cap.number_rx_channel);
3029 	seq_printf(seq, "\tNumber of Additional TX channel: %d\n",
3030 		   priv->dma_cap.number_tx_channel);
3031 	seq_printf(seq, "\tEnhanced descriptors: %s\n",
3032 		   (priv->dma_cap.enh_desc) ? "Y" : "N");
3033 
3034 	return 0;
3035 }
3036 
3037 static int stmmac_sysfs_dma_cap_open(struct inode *inode, struct file *file)
3038 {
3039 	return single_open(file, stmmac_sysfs_dma_cap_read, inode->i_private);
3040 }
3041 
3042 static const struct file_operations stmmac_dma_cap_fops = {
3043 	.owner = THIS_MODULE,
3044 	.open = stmmac_sysfs_dma_cap_open,
3045 	.read = seq_read,
3046 	.llseek = seq_lseek,
3047 	.release = single_release,
3048 };
3049 
3050 static int stmmac_init_fs(struct net_device *dev)
3051 {
3052 	struct stmmac_priv *priv = netdev_priv(dev);
3053 
3054 	/* Create per netdev entries */
3055 	priv->dbgfs_dir = debugfs_create_dir(dev->name, stmmac_fs_dir);
3056 
3057 	if (!priv->dbgfs_dir || IS_ERR(priv->dbgfs_dir)) {
3058 		netdev_err(priv->dev, "ERROR failed to create debugfs directory\n");
3059 
3060 		return -ENOMEM;
3061 	}
3062 
3063 	/* Entry to report DMA RX/TX rings */
3064 	priv->dbgfs_rings_status =
3065 		debugfs_create_file("descriptors_status", S_IRUGO,
3066 				    priv->dbgfs_dir, dev,
3067 				    &stmmac_rings_status_fops);
3068 
3069 	if (!priv->dbgfs_rings_status || IS_ERR(priv->dbgfs_rings_status)) {
3070 		netdev_err(priv->dev, "ERROR creating stmmac ring debugfs file\n");
3071 		debugfs_remove_recursive(priv->dbgfs_dir);
3072 
3073 		return -ENOMEM;
3074 	}
3075 
3076 	/* Entry to report the DMA HW features */
3077 	priv->dbgfs_dma_cap = debugfs_create_file("dma_cap", S_IRUGO,
3078 					    priv->dbgfs_dir,
3079 					    dev, &stmmac_dma_cap_fops);
3080 
3081 	if (!priv->dbgfs_dma_cap || IS_ERR(priv->dbgfs_dma_cap)) {
3082 		netdev_err(priv->dev, "ERROR creating stmmac MMC debugfs file\n");
3083 		debugfs_remove_recursive(priv->dbgfs_dir);
3084 
3085 		return -ENOMEM;
3086 	}
3087 
3088 	return 0;
3089 }
3090 
3091 static void stmmac_exit_fs(struct net_device *dev)
3092 {
3093 	struct stmmac_priv *priv = netdev_priv(dev);
3094 
3095 	debugfs_remove_recursive(priv->dbgfs_dir);
3096 }
3097 #endif /* CONFIG_DEBUG_FS */
3098 
3099 static const struct net_device_ops stmmac_netdev_ops = {
3100 	.ndo_open = stmmac_open,
3101 	.ndo_start_xmit = stmmac_xmit,
3102 	.ndo_stop = stmmac_release,
3103 	.ndo_change_mtu = stmmac_change_mtu,
3104 	.ndo_fix_features = stmmac_fix_features,
3105 	.ndo_set_features = stmmac_set_features,
3106 	.ndo_set_rx_mode = stmmac_set_rx_mode,
3107 	.ndo_tx_timeout = stmmac_tx_timeout,
3108 	.ndo_do_ioctl = stmmac_ioctl,
3109 #ifdef CONFIG_NET_POLL_CONTROLLER
3110 	.ndo_poll_controller = stmmac_poll_controller,
3111 #endif
3112 	.ndo_set_mac_address = eth_mac_addr,
3113 };
3114 
3115 /**
3116  *  stmmac_hw_init - Init the MAC device
3117  *  @priv: driver private structure
3118  *  Description: this function is to configure the MAC device according to
3119  *  some platform parameters or the HW capability register. It prepares the
3120  *  driver to use either ring or chain modes and to setup either enhanced or
3121  *  normal descriptors.
3122  */
3123 static int stmmac_hw_init(struct stmmac_priv *priv)
3124 {
3125 	struct mac_device_info *mac;
3126 
3127 	/* Identify the MAC HW device */
3128 	if (priv->plat->has_gmac) {
3129 		priv->dev->priv_flags |= IFF_UNICAST_FLT;
3130 		mac = dwmac1000_setup(priv->ioaddr,
3131 				      priv->plat->multicast_filter_bins,
3132 				      priv->plat->unicast_filter_entries,
3133 				      &priv->synopsys_id);
3134 	} else if (priv->plat->has_gmac4) {
3135 		priv->dev->priv_flags |= IFF_UNICAST_FLT;
3136 		mac = dwmac4_setup(priv->ioaddr,
3137 				   priv->plat->multicast_filter_bins,
3138 				   priv->plat->unicast_filter_entries,
3139 				   &priv->synopsys_id);
3140 	} else {
3141 		mac = dwmac100_setup(priv->ioaddr, &priv->synopsys_id);
3142 	}
3143 	if (!mac)
3144 		return -ENOMEM;
3145 
3146 	priv->hw = mac;
3147 
3148 	/* To use the chained or ring mode */
3149 	if (priv->synopsys_id >= DWMAC_CORE_4_00) {
3150 		priv->hw->mode = &dwmac4_ring_mode_ops;
3151 	} else {
3152 		if (chain_mode) {
3153 			priv->hw->mode = &chain_mode_ops;
3154 			dev_info(priv->device, "Chain mode enabled\n");
3155 			priv->mode = STMMAC_CHAIN_MODE;
3156 		} else {
3157 			priv->hw->mode = &ring_mode_ops;
3158 			dev_info(priv->device, "Ring mode enabled\n");
3159 			priv->mode = STMMAC_RING_MODE;
3160 		}
3161 	}
3162 
3163 	/* Get the HW capability (new GMAC newer than 3.50a) */
3164 	priv->hw_cap_support = stmmac_get_hw_features(priv);
3165 	if (priv->hw_cap_support) {
3166 		dev_info(priv->device, "DMA HW capability register supported\n");
3167 
3168 		/* We can override some gmac/dma configuration fields: e.g.
3169 		 * enh_desc, tx_coe (e.g. that are passed through the
3170 		 * platform) with the values from the HW capability
3171 		 * register (if supported).
3172 		 */
3173 		priv->plat->enh_desc = priv->dma_cap.enh_desc;
3174 		priv->plat->pmt = priv->dma_cap.pmt_remote_wake_up;
3175 		priv->hw->pmt = priv->plat->pmt;
3176 
3177 		/* TXCOE doesn't work in thresh DMA mode */
3178 		if (priv->plat->force_thresh_dma_mode)
3179 			priv->plat->tx_coe = 0;
3180 		else
3181 			priv->plat->tx_coe = priv->dma_cap.tx_coe;
3182 
3183 		/* In case of GMAC4 rx_coe is from HW cap register. */
3184 		priv->plat->rx_coe = priv->dma_cap.rx_coe;
3185 
3186 		if (priv->dma_cap.rx_coe_type2)
3187 			priv->plat->rx_coe = STMMAC_RX_COE_TYPE2;
3188 		else if (priv->dma_cap.rx_coe_type1)
3189 			priv->plat->rx_coe = STMMAC_RX_COE_TYPE1;
3190 
3191 	} else {
3192 		dev_info(priv->device, "No HW DMA feature register supported\n");
3193 	}
3194 
3195 	/* To use alternate (extended), normal or GMAC4 descriptor structures */
3196 	if (priv->synopsys_id >= DWMAC_CORE_4_00)
3197 		priv->hw->desc = &dwmac4_desc_ops;
3198 	else
3199 		stmmac_selec_desc_mode(priv);
3200 
3201 	if (priv->plat->rx_coe) {
3202 		priv->hw->rx_csum = priv->plat->rx_coe;
3203 		dev_info(priv->device, "RX Checksum Offload Engine supported\n");
3204 		if (priv->synopsys_id < DWMAC_CORE_4_00)
3205 			dev_info(priv->device, "COE Type %d\n", priv->hw->rx_csum);
3206 	}
3207 	if (priv->plat->tx_coe)
3208 		dev_info(priv->device, "TX Checksum insertion supported\n");
3209 
3210 	if (priv->plat->pmt) {
3211 		dev_info(priv->device, "Wake-Up On Lan supported\n");
3212 		device_set_wakeup_capable(priv->device, 1);
3213 	}
3214 
3215 	if (priv->dma_cap.tsoen)
3216 		dev_info(priv->device, "TSO supported\n");
3217 
3218 	return 0;
3219 }
3220 
3221 /**
3222  * stmmac_dvr_probe
3223  * @device: device pointer
3224  * @plat_dat: platform data pointer
3225  * @res: stmmac resource pointer
3226  * Description: this is the main probe function used to
3227  * call the alloc_etherdev, allocate the priv structure.
3228  * Return:
3229  * returns 0 on success, otherwise errno.
3230  */
3231 int stmmac_dvr_probe(struct device *device,
3232 		     struct plat_stmmacenet_data *plat_dat,
3233 		     struct stmmac_resources *res)
3234 {
3235 	int ret = 0;
3236 	struct net_device *ndev = NULL;
3237 	struct stmmac_priv *priv;
3238 
3239 	ndev = alloc_etherdev(sizeof(struct stmmac_priv));
3240 	if (!ndev)
3241 		return -ENOMEM;
3242 
3243 	SET_NETDEV_DEV(ndev, device);
3244 
3245 	priv = netdev_priv(ndev);
3246 	priv->device = device;
3247 	priv->dev = ndev;
3248 
3249 	stmmac_set_ethtool_ops(ndev);
3250 	priv->pause = pause;
3251 	priv->plat = plat_dat;
3252 	priv->ioaddr = res->addr;
3253 	priv->dev->base_addr = (unsigned long)res->addr;
3254 
3255 	priv->dev->irq = res->irq;
3256 	priv->wol_irq = res->wol_irq;
3257 	priv->lpi_irq = res->lpi_irq;
3258 
3259 	if (res->mac)
3260 		memcpy(priv->dev->dev_addr, res->mac, ETH_ALEN);
3261 
3262 	dev_set_drvdata(device, priv->dev);
3263 
3264 	/* Verify driver arguments */
3265 	stmmac_verify_args();
3266 
3267 	/* Override with kernel parameters if supplied XXX CRS XXX
3268 	 * this needs to have multiple instances
3269 	 */
3270 	if ((phyaddr >= 0) && (phyaddr <= 31))
3271 		priv->plat->phy_addr = phyaddr;
3272 
3273 	priv->stmmac_clk = devm_clk_get(priv->device, STMMAC_RESOURCE_NAME);
3274 	if (IS_ERR(priv->stmmac_clk)) {
3275 		netdev_warn(priv->dev, "%s: warning: cannot get CSR clock\n",
3276 			    __func__);
3277 		/* If failed to obtain stmmac_clk and specific clk_csr value
3278 		 * is NOT passed from the platform, probe fail.
3279 		 */
3280 		if (!priv->plat->clk_csr) {
3281 			ret = PTR_ERR(priv->stmmac_clk);
3282 			goto error_clk_get;
3283 		} else {
3284 			priv->stmmac_clk = NULL;
3285 		}
3286 	}
3287 	clk_prepare_enable(priv->stmmac_clk);
3288 
3289 	priv->pclk = devm_clk_get(priv->device, "pclk");
3290 	if (IS_ERR(priv->pclk)) {
3291 		if (PTR_ERR(priv->pclk) == -EPROBE_DEFER) {
3292 			ret = -EPROBE_DEFER;
3293 			goto error_pclk_get;
3294 		}
3295 		priv->pclk = NULL;
3296 	}
3297 	clk_prepare_enable(priv->pclk);
3298 
3299 	priv->stmmac_rst = devm_reset_control_get(priv->device,
3300 						  STMMAC_RESOURCE_NAME);
3301 	if (IS_ERR(priv->stmmac_rst)) {
3302 		if (PTR_ERR(priv->stmmac_rst) == -EPROBE_DEFER) {
3303 			ret = -EPROBE_DEFER;
3304 			goto error_hw_init;
3305 		}
3306 		dev_info(priv->device, "no reset control found\n");
3307 		priv->stmmac_rst = NULL;
3308 	}
3309 	if (priv->stmmac_rst)
3310 		reset_control_deassert(priv->stmmac_rst);
3311 
3312 	/* Init MAC and get the capabilities */
3313 	ret = stmmac_hw_init(priv);
3314 	if (ret)
3315 		goto error_hw_init;
3316 
3317 	ndev->netdev_ops = &stmmac_netdev_ops;
3318 
3319 	ndev->hw_features = NETIF_F_SG | NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM |
3320 			    NETIF_F_RXCSUM;
3321 
3322 	if ((priv->plat->tso_en) && (priv->dma_cap.tsoen)) {
3323 		ndev->hw_features |= NETIF_F_TSO;
3324 		priv->tso = true;
3325 		dev_info(priv->device, "TSO feature enabled\n");
3326 	}
3327 	ndev->features |= ndev->hw_features | NETIF_F_HIGHDMA;
3328 	ndev->watchdog_timeo = msecs_to_jiffies(watchdog);
3329 #ifdef STMMAC_VLAN_TAG_USED
3330 	/* Both mac100 and gmac support receive VLAN tag detection */
3331 	ndev->features |= NETIF_F_HW_VLAN_CTAG_RX;
3332 #endif
3333 	priv->msg_enable = netif_msg_init(debug, default_msg_level);
3334 
3335 	/* MTU range: 46 - hw-specific max */
3336 	ndev->min_mtu = ETH_ZLEN - ETH_HLEN;
3337 	if ((priv->plat->enh_desc) || (priv->synopsys_id >= DWMAC_CORE_4_00))
3338 		ndev->max_mtu = JUMBO_LEN;
3339 	else
3340 		ndev->max_mtu = SKB_MAX_HEAD(NET_SKB_PAD + NET_IP_ALIGN);
3341 	if (priv->plat->maxmtu < ndev->max_mtu)
3342 		ndev->max_mtu = priv->plat->maxmtu;
3343 
3344 	if (flow_ctrl)
3345 		priv->flow_ctrl = FLOW_AUTO;	/* RX/TX pause on */
3346 
3347 	/* Rx Watchdog is available in the COREs newer than the 3.40.
3348 	 * In some case, for example on bugged HW this feature
3349 	 * has to be disable and this can be done by passing the
3350 	 * riwt_off field from the platform.
3351 	 */
3352 	if ((priv->synopsys_id >= DWMAC_CORE_3_50) && (!priv->plat->riwt_off)) {
3353 		priv->use_riwt = 1;
3354 		netdev_info(priv->dev, "Enable RX Mitigation via HW Watchdog Timer\n");
3355 	}
3356 
3357 	netif_napi_add(ndev, &priv->napi, stmmac_poll, 64);
3358 
3359 	spin_lock_init(&priv->lock);
3360 	spin_lock_init(&priv->tx_lock);
3361 
3362 	ret = register_netdev(ndev);
3363 	if (ret) {
3364 		netdev_err(priv->dev, "%s: ERROR %i registering the device\n",
3365 			   __func__, ret);
3366 		goto error_netdev_register;
3367 	}
3368 
3369 	/* If a specific clk_csr value is passed from the platform
3370 	 * this means that the CSR Clock Range selection cannot be
3371 	 * changed at run-time and it is fixed. Viceversa the driver'll try to
3372 	 * set the MDC clock dynamically according to the csr actual
3373 	 * clock input.
3374 	 */
3375 	if (!priv->plat->clk_csr)
3376 		stmmac_clk_csr_set(priv);
3377 	else
3378 		priv->clk_csr = priv->plat->clk_csr;
3379 
3380 	stmmac_check_pcs_mode(priv);
3381 
3382 	if (priv->hw->pcs != STMMAC_PCS_RGMII  &&
3383 	    priv->hw->pcs != STMMAC_PCS_TBI &&
3384 	    priv->hw->pcs != STMMAC_PCS_RTBI) {
3385 		/* MDIO bus Registration */
3386 		ret = stmmac_mdio_register(ndev);
3387 		if (ret < 0) {
3388 			netdev_err(priv->dev,
3389 				   "%s: MDIO bus (id: %d) registration failed",
3390 				   __func__, priv->plat->bus_id);
3391 			goto error_mdio_register;
3392 		}
3393 	}
3394 
3395 	return 0;
3396 
3397 error_mdio_register:
3398 	unregister_netdev(ndev);
3399 error_netdev_register:
3400 	netif_napi_del(&priv->napi);
3401 error_hw_init:
3402 	clk_disable_unprepare(priv->pclk);
3403 error_pclk_get:
3404 	clk_disable_unprepare(priv->stmmac_clk);
3405 error_clk_get:
3406 	free_netdev(ndev);
3407 
3408 	return ret;
3409 }
3410 EXPORT_SYMBOL_GPL(stmmac_dvr_probe);
3411 
3412 /**
3413  * stmmac_dvr_remove
3414  * @dev: device pointer
3415  * Description: this function resets the TX/RX processes, disables the MAC RX/TX
3416  * changes the link status, releases the DMA descriptor rings.
3417  */
3418 int stmmac_dvr_remove(struct device *dev)
3419 {
3420 	struct net_device *ndev = dev_get_drvdata(dev);
3421 	struct stmmac_priv *priv = netdev_priv(ndev);
3422 
3423 	netdev_info(priv->dev, "%s: removing driver", __func__);
3424 
3425 	priv->hw->dma->stop_rx(priv->ioaddr);
3426 	priv->hw->dma->stop_tx(priv->ioaddr);
3427 
3428 	stmmac_set_mac(priv->ioaddr, false);
3429 	netif_carrier_off(ndev);
3430 	unregister_netdev(ndev);
3431 	if (priv->stmmac_rst)
3432 		reset_control_assert(priv->stmmac_rst);
3433 	clk_disable_unprepare(priv->pclk);
3434 	clk_disable_unprepare(priv->stmmac_clk);
3435 	if (priv->hw->pcs != STMMAC_PCS_RGMII &&
3436 	    priv->hw->pcs != STMMAC_PCS_TBI &&
3437 	    priv->hw->pcs != STMMAC_PCS_RTBI)
3438 		stmmac_mdio_unregister(ndev);
3439 	free_netdev(ndev);
3440 
3441 	return 0;
3442 }
3443 EXPORT_SYMBOL_GPL(stmmac_dvr_remove);
3444 
3445 /**
3446  * stmmac_suspend - suspend callback
3447  * @dev: device pointer
3448  * Description: this is the function to suspend the device and it is called
3449  * by the platform driver to stop the network queue, release the resources,
3450  * program the PMT register (for WoL), clean and release driver resources.
3451  */
3452 int stmmac_suspend(struct device *dev)
3453 {
3454 	struct net_device *ndev = dev_get_drvdata(dev);
3455 	struct stmmac_priv *priv = netdev_priv(ndev);
3456 	unsigned long flags;
3457 
3458 	if (!ndev || !netif_running(ndev))
3459 		return 0;
3460 
3461 	if (ndev->phydev)
3462 		phy_stop(ndev->phydev);
3463 
3464 	spin_lock_irqsave(&priv->lock, flags);
3465 
3466 	netif_device_detach(ndev);
3467 	netif_stop_queue(ndev);
3468 
3469 	napi_disable(&priv->napi);
3470 
3471 	/* Stop TX/RX DMA */
3472 	priv->hw->dma->stop_tx(priv->ioaddr);
3473 	priv->hw->dma->stop_rx(priv->ioaddr);
3474 
3475 	/* Enable Power down mode by programming the PMT regs */
3476 	if (device_may_wakeup(priv->device)) {
3477 		priv->hw->mac->pmt(priv->hw, priv->wolopts);
3478 		priv->irq_wake = 1;
3479 	} else {
3480 		stmmac_set_mac(priv->ioaddr, false);
3481 		pinctrl_pm_select_sleep_state(priv->device);
3482 		/* Disable clock in case of PWM is off */
3483 		clk_disable(priv->pclk);
3484 		clk_disable(priv->stmmac_clk);
3485 	}
3486 	spin_unlock_irqrestore(&priv->lock, flags);
3487 
3488 	priv->oldlink = 0;
3489 	priv->speed = 0;
3490 	priv->oldduplex = -1;
3491 	return 0;
3492 }
3493 EXPORT_SYMBOL_GPL(stmmac_suspend);
3494 
3495 /**
3496  * stmmac_resume - resume callback
3497  * @dev: device pointer
3498  * Description: when resume this function is invoked to setup the DMA and CORE
3499  * in a usable state.
3500  */
3501 int stmmac_resume(struct device *dev)
3502 {
3503 	struct net_device *ndev = dev_get_drvdata(dev);
3504 	struct stmmac_priv *priv = netdev_priv(ndev);
3505 	unsigned long flags;
3506 
3507 	if (!netif_running(ndev))
3508 		return 0;
3509 
3510 	/* Power Down bit, into the PM register, is cleared
3511 	 * automatically as soon as a magic packet or a Wake-up frame
3512 	 * is received. Anyway, it's better to manually clear
3513 	 * this bit because it can generate problems while resuming
3514 	 * from another devices (e.g. serial console).
3515 	 */
3516 	if (device_may_wakeup(priv->device)) {
3517 		spin_lock_irqsave(&priv->lock, flags);
3518 		priv->hw->mac->pmt(priv->hw, 0);
3519 		spin_unlock_irqrestore(&priv->lock, flags);
3520 		priv->irq_wake = 0;
3521 	} else {
3522 		pinctrl_pm_select_default_state(priv->device);
3523 		/* enable the clk prevously disabled */
3524 		clk_enable(priv->stmmac_clk);
3525 		clk_enable(priv->pclk);
3526 		/* reset the phy so that it's ready */
3527 		if (priv->mii)
3528 			stmmac_mdio_reset(priv->mii);
3529 	}
3530 
3531 	netif_device_attach(ndev);
3532 
3533 	spin_lock_irqsave(&priv->lock, flags);
3534 
3535 	priv->cur_rx = 0;
3536 	priv->dirty_rx = 0;
3537 	priv->dirty_tx = 0;
3538 	priv->cur_tx = 0;
3539 	/* reset private mss value to force mss context settings at
3540 	 * next tso xmit (only used for gmac4).
3541 	 */
3542 	priv->mss = 0;
3543 
3544 	stmmac_clear_descriptors(priv);
3545 
3546 	stmmac_hw_setup(ndev, false);
3547 	stmmac_init_tx_coalesce(priv);
3548 	stmmac_set_rx_mode(ndev);
3549 
3550 	napi_enable(&priv->napi);
3551 
3552 	netif_start_queue(ndev);
3553 
3554 	spin_unlock_irqrestore(&priv->lock, flags);
3555 
3556 	if (ndev->phydev)
3557 		phy_start(ndev->phydev);
3558 
3559 	return 0;
3560 }
3561 EXPORT_SYMBOL_GPL(stmmac_resume);
3562 
3563 #ifndef MODULE
3564 static int __init stmmac_cmdline_opt(char *str)
3565 {
3566 	char *opt;
3567 
3568 	if (!str || !*str)
3569 		return -EINVAL;
3570 	while ((opt = strsep(&str, ",")) != NULL) {
3571 		if (!strncmp(opt, "debug:", 6)) {
3572 			if (kstrtoint(opt + 6, 0, &debug))
3573 				goto err;
3574 		} else if (!strncmp(opt, "phyaddr:", 8)) {
3575 			if (kstrtoint(opt + 8, 0, &phyaddr))
3576 				goto err;
3577 		} else if (!strncmp(opt, "buf_sz:", 7)) {
3578 			if (kstrtoint(opt + 7, 0, &buf_sz))
3579 				goto err;
3580 		} else if (!strncmp(opt, "tc:", 3)) {
3581 			if (kstrtoint(opt + 3, 0, &tc))
3582 				goto err;
3583 		} else if (!strncmp(opt, "watchdog:", 9)) {
3584 			if (kstrtoint(opt + 9, 0, &watchdog))
3585 				goto err;
3586 		} else if (!strncmp(opt, "flow_ctrl:", 10)) {
3587 			if (kstrtoint(opt + 10, 0, &flow_ctrl))
3588 				goto err;
3589 		} else if (!strncmp(opt, "pause:", 6)) {
3590 			if (kstrtoint(opt + 6, 0, &pause))
3591 				goto err;
3592 		} else if (!strncmp(opt, "eee_timer:", 10)) {
3593 			if (kstrtoint(opt + 10, 0, &eee_timer))
3594 				goto err;
3595 		} else if (!strncmp(opt, "chain_mode:", 11)) {
3596 			if (kstrtoint(opt + 11, 0, &chain_mode))
3597 				goto err;
3598 		}
3599 	}
3600 	return 0;
3601 
3602 err:
3603 	pr_err("%s: ERROR broken module parameter conversion", __func__);
3604 	return -EINVAL;
3605 }
3606 
3607 __setup("stmmaceth=", stmmac_cmdline_opt);
3608 #endif /* MODULE */
3609 
3610 static int __init stmmac_init(void)
3611 {
3612 #ifdef CONFIG_DEBUG_FS
3613 	/* Create debugfs main directory if it doesn't exist yet */
3614 	if (!stmmac_fs_dir) {
3615 		stmmac_fs_dir = debugfs_create_dir(STMMAC_RESOURCE_NAME, NULL);
3616 
3617 		if (!stmmac_fs_dir || IS_ERR(stmmac_fs_dir)) {
3618 			pr_err("ERROR %s, debugfs create directory failed\n",
3619 			       STMMAC_RESOURCE_NAME);
3620 
3621 			return -ENOMEM;
3622 		}
3623 	}
3624 #endif
3625 
3626 	return 0;
3627 }
3628 
3629 static void __exit stmmac_exit(void)
3630 {
3631 #ifdef CONFIG_DEBUG_FS
3632 	debugfs_remove_recursive(stmmac_fs_dir);
3633 #endif
3634 }
3635 
3636 module_init(stmmac_init)
3637 module_exit(stmmac_exit)
3638 
3639 MODULE_DESCRIPTION("STMMAC 10/100/1000 Ethernet device driver");
3640 MODULE_AUTHOR("Giuseppe Cavallaro <peppe.cavallaro@st.com>");
3641 MODULE_LICENSE("GPL");
3642