xref: /openbmc/linux/drivers/net/ethernet/cortina/gemini.c (revision 0760aad038b5a032c31ea124feed63d88627d2f1)
1 // SPDX-License-Identifier: GPL-2.0
2 /* Ethernet device driver for Cortina Systems Gemini SoC
3  * Also known as the StorLink SL3512 and SL3516 (SL351x) or Lepus
4  * Net Engine and Gigabit Ethernet MAC (GMAC)
5  * This hardware contains a TCP Offload Engine (TOE) but currently the
6  * driver does not make use of it.
7  *
8  * Authors:
9  * Linus Walleij <linus.walleij@linaro.org>
10  * Tobias Waldvogel <tobias.waldvogel@gmail.com> (OpenWRT)
11  * Michał Mirosław <mirq-linux@rere.qmqm.pl>
12  * Paulius Zaleckas <paulius.zaleckas@gmail.com>
13  * Giuseppe De Robertis <Giuseppe.DeRobertis@ba.infn.it>
14  * Gary Chen & Ch Hsu Storlink Semiconductor
15  */
16 #include <linux/kernel.h>
17 #include <linux/init.h>
18 #include <linux/module.h>
19 #include <linux/platform_device.h>
20 #include <linux/spinlock.h>
21 #include <linux/slab.h>
22 #include <linux/dma-mapping.h>
23 #include <linux/cache.h>
24 #include <linux/interrupt.h>
25 #include <linux/reset.h>
26 #include <linux/clk.h>
27 #include <linux/of.h>
28 #include <linux/of_mdio.h>
29 #include <linux/of_net.h>
30 #include <linux/of_platform.h>
31 #include <linux/etherdevice.h>
32 #include <linux/if_vlan.h>
33 #include <linux/skbuff.h>
34 #include <linux/phy.h>
35 #include <linux/crc32.h>
36 #include <linux/ethtool.h>
37 #include <linux/tcp.h>
38 #include <linux/u64_stats_sync.h>
39 
40 #include <linux/in.h>
41 #include <linux/ip.h>
42 #include <linux/ipv6.h>
43 
44 #include "gemini.h"
45 
46 #define DRV_NAME		"gmac-gemini"
47 
48 #define DEFAULT_MSG_ENABLE (NETIF_MSG_DRV | NETIF_MSG_PROBE | NETIF_MSG_LINK)
49 static int debug = -1;
50 module_param(debug, int, 0);
51 MODULE_PARM_DESC(debug, "Debug level (0=none,...,16=all)");
52 
53 #define HSIZE_8			0x00
54 #define HSIZE_16		0x01
55 #define HSIZE_32		0x02
56 
57 #define HBURST_SINGLE		0x00
58 #define HBURST_INCR		0x01
59 #define HBURST_INCR4		0x02
60 #define HBURST_INCR8		0x03
61 
62 #define HPROT_DATA_CACHE	BIT(0)
63 #define HPROT_PRIVILIGED	BIT(1)
64 #define HPROT_BUFFERABLE	BIT(2)
65 #define HPROT_CACHABLE		BIT(3)
66 
67 #define DEFAULT_RX_COALESCE_NSECS	0
68 #define DEFAULT_GMAC_RXQ_ORDER		9
69 #define DEFAULT_GMAC_TXQ_ORDER		8
70 #define DEFAULT_RX_BUF_ORDER		11
71 #define DEFAULT_NAPI_WEIGHT		64
72 #define TX_MAX_FRAGS			16
73 #define TX_QUEUE_NUM			1	/* max: 6 */
74 #define RX_MAX_ALLOC_ORDER		2
75 
76 #define GMAC0_IRQ0_2 (GMAC0_TXDERR_INT_BIT | GMAC0_TXPERR_INT_BIT | \
77 		      GMAC0_RXDERR_INT_BIT | GMAC0_RXPERR_INT_BIT)
78 #define GMAC0_IRQ0_TXQ0_INTS (GMAC0_SWTQ00_EOF_INT_BIT | \
79 			      GMAC0_SWTQ00_FIN_INT_BIT)
80 #define GMAC0_IRQ4_8 (GMAC0_MIB_INT_BIT | GMAC0_RX_OVERRUN_INT_BIT)
81 
82 #define GMAC_OFFLOAD_FEATURES (NETIF_F_SG | NETIF_F_IP_CSUM | \
83 		NETIF_F_IPV6_CSUM | NETIF_F_RXCSUM | \
84 		NETIF_F_TSO | NETIF_F_TSO_ECN | NETIF_F_TSO6)
85 
86 /**
87  * struct gmac_queue_page - page buffer per-page info
88  */
89 struct gmac_queue_page {
90 	struct page *page;
91 	dma_addr_t mapping;
92 };
93 
94 struct gmac_txq {
95 	struct gmac_txdesc *ring;
96 	struct sk_buff	**skb;
97 	unsigned int	cptr;
98 	unsigned int	noirq_packets;
99 };
100 
101 struct gemini_ethernet;
102 
103 struct gemini_ethernet_port {
104 	u8 id; /* 0 or 1 */
105 
106 	struct gemini_ethernet *geth;
107 	struct net_device *netdev;
108 	struct device *dev;
109 	void __iomem *dma_base;
110 	void __iomem *gmac_base;
111 	struct clk *pclk;
112 	struct reset_control *reset;
113 	int irq;
114 	__le32 mac_addr[3];
115 
116 	void __iomem		*rxq_rwptr;
117 	struct gmac_rxdesc	*rxq_ring;
118 	unsigned int		rxq_order;
119 
120 	struct napi_struct	napi;
121 	struct hrtimer		rx_coalesce_timer;
122 	unsigned int		rx_coalesce_nsecs;
123 	unsigned int		freeq_refill;
124 	struct gmac_txq		txq[TX_QUEUE_NUM];
125 	unsigned int		txq_order;
126 	unsigned int		irq_every_tx_packets;
127 
128 	dma_addr_t		rxq_dma_base;
129 	dma_addr_t		txq_dma_base;
130 
131 	unsigned int		msg_enable;
132 	spinlock_t		config_lock; /* Locks config register */
133 
134 	struct u64_stats_sync	tx_stats_syncp;
135 	struct u64_stats_sync	rx_stats_syncp;
136 	struct u64_stats_sync	ir_stats_syncp;
137 
138 	struct rtnl_link_stats64 stats;
139 	u64			hw_stats[RX_STATS_NUM];
140 	u64			rx_stats[RX_STATUS_NUM];
141 	u64			rx_csum_stats[RX_CHKSUM_NUM];
142 	u64			rx_napi_exits;
143 	u64			tx_frag_stats[TX_MAX_FRAGS];
144 	u64			tx_frags_linearized;
145 	u64			tx_hw_csummed;
146 };
147 
148 struct gemini_ethernet {
149 	struct device *dev;
150 	void __iomem *base;
151 	struct gemini_ethernet_port *port0;
152 	struct gemini_ethernet_port *port1;
153 	bool initialized;
154 
155 	spinlock_t	irq_lock; /* Locks IRQ-related registers */
156 	unsigned int	freeq_order;
157 	unsigned int	freeq_frag_order;
158 	struct gmac_rxdesc *freeq_ring;
159 	dma_addr_t	freeq_dma_base;
160 	struct gmac_queue_page	*freeq_pages;
161 	unsigned int	num_freeq_pages;
162 	spinlock_t	freeq_lock; /* Locks queue from reentrance */
163 };
164 
165 #define GMAC_STATS_NUM	( \
166 	RX_STATS_NUM + RX_STATUS_NUM + RX_CHKSUM_NUM + 1 + \
167 	TX_MAX_FRAGS + 2)
168 
169 static const char gmac_stats_strings[GMAC_STATS_NUM][ETH_GSTRING_LEN] = {
170 	"GMAC_IN_DISCARDS",
171 	"GMAC_IN_ERRORS",
172 	"GMAC_IN_MCAST",
173 	"GMAC_IN_BCAST",
174 	"GMAC_IN_MAC1",
175 	"GMAC_IN_MAC2",
176 	"RX_STATUS_GOOD_FRAME",
177 	"RX_STATUS_TOO_LONG_GOOD_CRC",
178 	"RX_STATUS_RUNT_FRAME",
179 	"RX_STATUS_SFD_NOT_FOUND",
180 	"RX_STATUS_CRC_ERROR",
181 	"RX_STATUS_TOO_LONG_BAD_CRC",
182 	"RX_STATUS_ALIGNMENT_ERROR",
183 	"RX_STATUS_TOO_LONG_BAD_ALIGN",
184 	"RX_STATUS_RX_ERR",
185 	"RX_STATUS_DA_FILTERED",
186 	"RX_STATUS_BUFFER_FULL",
187 	"RX_STATUS_11",
188 	"RX_STATUS_12",
189 	"RX_STATUS_13",
190 	"RX_STATUS_14",
191 	"RX_STATUS_15",
192 	"RX_CHKSUM_IP_UDP_TCP_OK",
193 	"RX_CHKSUM_IP_OK_ONLY",
194 	"RX_CHKSUM_NONE",
195 	"RX_CHKSUM_3",
196 	"RX_CHKSUM_IP_ERR_UNKNOWN",
197 	"RX_CHKSUM_IP_ERR",
198 	"RX_CHKSUM_TCP_UDP_ERR",
199 	"RX_CHKSUM_7",
200 	"RX_NAPI_EXITS",
201 	"TX_FRAGS[1]",
202 	"TX_FRAGS[2]",
203 	"TX_FRAGS[3]",
204 	"TX_FRAGS[4]",
205 	"TX_FRAGS[5]",
206 	"TX_FRAGS[6]",
207 	"TX_FRAGS[7]",
208 	"TX_FRAGS[8]",
209 	"TX_FRAGS[9]",
210 	"TX_FRAGS[10]",
211 	"TX_FRAGS[11]",
212 	"TX_FRAGS[12]",
213 	"TX_FRAGS[13]",
214 	"TX_FRAGS[14]",
215 	"TX_FRAGS[15]",
216 	"TX_FRAGS[16+]",
217 	"TX_FRAGS_LINEARIZED",
218 	"TX_HW_CSUMMED",
219 };
220 
221 static void gmac_dump_dma_state(struct net_device *netdev);
222 
223 static void gmac_update_config0_reg(struct net_device *netdev,
224 				    u32 val, u32 vmask)
225 {
226 	struct gemini_ethernet_port *port = netdev_priv(netdev);
227 	unsigned long flags;
228 	u32 reg;
229 
230 	spin_lock_irqsave(&port->config_lock, flags);
231 
232 	reg = readl(port->gmac_base + GMAC_CONFIG0);
233 	reg = (reg & ~vmask) | val;
234 	writel(reg, port->gmac_base + GMAC_CONFIG0);
235 
236 	spin_unlock_irqrestore(&port->config_lock, flags);
237 }
238 
239 static void gmac_enable_tx_rx(struct net_device *netdev)
240 {
241 	struct gemini_ethernet_port *port = netdev_priv(netdev);
242 	unsigned long flags;
243 	u32 reg;
244 
245 	spin_lock_irqsave(&port->config_lock, flags);
246 
247 	reg = readl(port->gmac_base + GMAC_CONFIG0);
248 	reg &= ~CONFIG0_TX_RX_DISABLE;
249 	writel(reg, port->gmac_base + GMAC_CONFIG0);
250 
251 	spin_unlock_irqrestore(&port->config_lock, flags);
252 }
253 
254 static void gmac_disable_tx_rx(struct net_device *netdev)
255 {
256 	struct gemini_ethernet_port *port = netdev_priv(netdev);
257 	unsigned long flags;
258 	u32 val;
259 
260 	spin_lock_irqsave(&port->config_lock, flags);
261 
262 	val = readl(port->gmac_base + GMAC_CONFIG0);
263 	val |= CONFIG0_TX_RX_DISABLE;
264 	writel(val, port->gmac_base + GMAC_CONFIG0);
265 
266 	spin_unlock_irqrestore(&port->config_lock, flags);
267 
268 	mdelay(10);	/* let GMAC consume packet */
269 }
270 
271 static void gmac_set_flow_control(struct net_device *netdev, bool tx, bool rx)
272 {
273 	struct gemini_ethernet_port *port = netdev_priv(netdev);
274 	unsigned long flags;
275 	u32 val;
276 
277 	spin_lock_irqsave(&port->config_lock, flags);
278 
279 	val = readl(port->gmac_base + GMAC_CONFIG0);
280 	val &= ~CONFIG0_FLOW_CTL;
281 	if (tx)
282 		val |= CONFIG0_FLOW_TX;
283 	if (rx)
284 		val |= CONFIG0_FLOW_RX;
285 	writel(val, port->gmac_base + GMAC_CONFIG0);
286 
287 	spin_unlock_irqrestore(&port->config_lock, flags);
288 }
289 
290 static void gmac_speed_set(struct net_device *netdev)
291 {
292 	struct gemini_ethernet_port *port = netdev_priv(netdev);
293 	struct phy_device *phydev = netdev->phydev;
294 	union gmac_status status, old_status;
295 	int pause_tx = 0;
296 	int pause_rx = 0;
297 
298 	status.bits32 = readl(port->gmac_base + GMAC_STATUS);
299 	old_status.bits32 = status.bits32;
300 	status.bits.link = phydev->link;
301 	status.bits.duplex = phydev->duplex;
302 
303 	switch (phydev->speed) {
304 	case 1000:
305 		status.bits.speed = GMAC_SPEED_1000;
306 		if (phydev->interface == PHY_INTERFACE_MODE_RGMII)
307 			status.bits.mii_rmii = GMAC_PHY_RGMII_1000;
308 		netdev_dbg(netdev, "connect %s to RGMII @ 1Gbit\n",
309 			   phydev_name(phydev));
310 		break;
311 	case 100:
312 		status.bits.speed = GMAC_SPEED_100;
313 		if (phydev->interface == PHY_INTERFACE_MODE_RGMII)
314 			status.bits.mii_rmii = GMAC_PHY_RGMII_100_10;
315 		netdev_dbg(netdev, "connect %s to RGMII @ 100 Mbit\n",
316 			   phydev_name(phydev));
317 		break;
318 	case 10:
319 		status.bits.speed = GMAC_SPEED_10;
320 		if (phydev->interface == PHY_INTERFACE_MODE_RGMII)
321 			status.bits.mii_rmii = GMAC_PHY_RGMII_100_10;
322 		netdev_dbg(netdev, "connect %s to RGMII @ 10 Mbit\n",
323 			   phydev_name(phydev));
324 		break;
325 	default:
326 		netdev_warn(netdev, "Unsupported PHY speed (%d) on %s\n",
327 			    phydev->speed, phydev_name(phydev));
328 	}
329 
330 	if (phydev->duplex == DUPLEX_FULL) {
331 		u16 lcladv = phy_read(phydev, MII_ADVERTISE);
332 		u16 rmtadv = phy_read(phydev, MII_LPA);
333 		u8 cap = mii_resolve_flowctrl_fdx(lcladv, rmtadv);
334 
335 		if (cap & FLOW_CTRL_RX)
336 			pause_rx = 1;
337 		if (cap & FLOW_CTRL_TX)
338 			pause_tx = 1;
339 	}
340 
341 	gmac_set_flow_control(netdev, pause_tx, pause_rx);
342 
343 	if (old_status.bits32 == status.bits32)
344 		return;
345 
346 	if (netif_msg_link(port)) {
347 		phy_print_status(phydev);
348 		netdev_info(netdev, "link flow control: %s\n",
349 			    phydev->pause
350 			    ? (phydev->asym_pause ? "tx" : "both")
351 			    : (phydev->asym_pause ? "rx" : "none")
352 		);
353 	}
354 
355 	gmac_disable_tx_rx(netdev);
356 	writel(status.bits32, port->gmac_base + GMAC_STATUS);
357 	gmac_enable_tx_rx(netdev);
358 }
359 
360 static int gmac_setup_phy(struct net_device *netdev)
361 {
362 	struct gemini_ethernet_port *port = netdev_priv(netdev);
363 	union gmac_status status = { .bits32 = 0 };
364 	struct device *dev = port->dev;
365 	struct phy_device *phy;
366 
367 	phy = of_phy_get_and_connect(netdev,
368 				     dev->of_node,
369 				     gmac_speed_set);
370 	if (!phy)
371 		return -ENODEV;
372 	netdev->phydev = phy;
373 
374 	phy_set_max_speed(phy, SPEED_1000);
375 	phy_support_asym_pause(phy);
376 
377 	/* set PHY interface type */
378 	switch (phy->interface) {
379 	case PHY_INTERFACE_MODE_MII:
380 		netdev_dbg(netdev,
381 			   "MII: set GMAC0 to GMII mode, GMAC1 disabled\n");
382 		status.bits.mii_rmii = GMAC_PHY_MII;
383 		break;
384 	case PHY_INTERFACE_MODE_GMII:
385 		netdev_dbg(netdev,
386 			   "GMII: set GMAC0 to GMII mode, GMAC1 disabled\n");
387 		status.bits.mii_rmii = GMAC_PHY_GMII;
388 		break;
389 	case PHY_INTERFACE_MODE_RGMII:
390 		netdev_dbg(netdev,
391 			   "RGMII: set GMAC0 and GMAC1 to MII/RGMII mode\n");
392 		status.bits.mii_rmii = GMAC_PHY_RGMII_100_10;
393 		break;
394 	default:
395 		netdev_err(netdev, "Unsupported MII interface\n");
396 		phy_disconnect(phy);
397 		netdev->phydev = NULL;
398 		return -EINVAL;
399 	}
400 	writel(status.bits32, port->gmac_base + GMAC_STATUS);
401 
402 	if (netif_msg_link(port))
403 		phy_attached_info(phy);
404 
405 	return 0;
406 }
407 
408 /* The maximum frame length is not logically enumerated in the
409  * hardware, so we do a table lookup to find the applicable max
410  * frame length.
411  */
412 struct gmac_max_framelen {
413 	unsigned int max_l3_len;
414 	u8 val;
415 };
416 
417 static const struct gmac_max_framelen gmac_maxlens[] = {
418 	{
419 		.max_l3_len = 1518,
420 		.val = CONFIG0_MAXLEN_1518,
421 	},
422 	{
423 		.max_l3_len = 1522,
424 		.val = CONFIG0_MAXLEN_1522,
425 	},
426 	{
427 		.max_l3_len = 1536,
428 		.val = CONFIG0_MAXLEN_1536,
429 	},
430 	{
431 		.max_l3_len = 1542,
432 		.val = CONFIG0_MAXLEN_1542,
433 	},
434 	{
435 		.max_l3_len = 9212,
436 		.val = CONFIG0_MAXLEN_9k,
437 	},
438 	{
439 		.max_l3_len = 10236,
440 		.val = CONFIG0_MAXLEN_10k,
441 	},
442 };
443 
444 static int gmac_pick_rx_max_len(unsigned int max_l3_len)
445 {
446 	const struct gmac_max_framelen *maxlen;
447 	int maxtot;
448 	int i;
449 
450 	maxtot = max_l3_len + ETH_HLEN + VLAN_HLEN;
451 
452 	for (i = 0; i < ARRAY_SIZE(gmac_maxlens); i++) {
453 		maxlen = &gmac_maxlens[i];
454 		if (maxtot <= maxlen->max_l3_len)
455 			return maxlen->val;
456 	}
457 
458 	return -1;
459 }
460 
461 static int gmac_init(struct net_device *netdev)
462 {
463 	struct gemini_ethernet_port *port = netdev_priv(netdev);
464 	union gmac_config0 config0 = { .bits = {
465 		.dis_tx = 1,
466 		.dis_rx = 1,
467 		.ipv4_rx_chksum = 1,
468 		.ipv6_rx_chksum = 1,
469 		.rx_err_detect = 1,
470 		.rgmm_edge = 1,
471 		.port0_chk_hwq = 1,
472 		.port1_chk_hwq = 1,
473 		.port0_chk_toeq = 1,
474 		.port1_chk_toeq = 1,
475 		.port0_chk_classq = 1,
476 		.port1_chk_classq = 1,
477 	} };
478 	union gmac_ahb_weight ahb_weight = { .bits = {
479 		.rx_weight = 1,
480 		.tx_weight = 1,
481 		.hash_weight = 1,
482 		.pre_req = 0x1f,
483 		.tq_dv_threshold = 0,
484 	} };
485 	union gmac_tx_wcr0 hw_weigh = { .bits = {
486 		.hw_tq3 = 1,
487 		.hw_tq2 = 1,
488 		.hw_tq1 = 1,
489 		.hw_tq0 = 1,
490 	} };
491 	union gmac_tx_wcr1 sw_weigh = { .bits = {
492 		.sw_tq5 = 1,
493 		.sw_tq4 = 1,
494 		.sw_tq3 = 1,
495 		.sw_tq2 = 1,
496 		.sw_tq1 = 1,
497 		.sw_tq0 = 1,
498 	} };
499 	union gmac_config1 config1 = { .bits = {
500 		.set_threshold = 16,
501 		.rel_threshold = 24,
502 	} };
503 	union gmac_config2 config2 = { .bits = {
504 		.set_threshold = 16,
505 		.rel_threshold = 32,
506 	} };
507 	union gmac_config3 config3 = { .bits = {
508 		.set_threshold = 0,
509 		.rel_threshold = 0,
510 	} };
511 	union gmac_config0 tmp;
512 	u32 val;
513 
514 	config0.bits.max_len = gmac_pick_rx_max_len(netdev->mtu);
515 	tmp.bits32 = readl(port->gmac_base + GMAC_CONFIG0);
516 	config0.bits.reserved = tmp.bits.reserved;
517 	writel(config0.bits32, port->gmac_base + GMAC_CONFIG0);
518 	writel(config1.bits32, port->gmac_base + GMAC_CONFIG1);
519 	writel(config2.bits32, port->gmac_base + GMAC_CONFIG2);
520 	writel(config3.bits32, port->gmac_base + GMAC_CONFIG3);
521 
522 	val = readl(port->dma_base + GMAC_AHB_WEIGHT_REG);
523 	writel(ahb_weight.bits32, port->dma_base + GMAC_AHB_WEIGHT_REG);
524 
525 	writel(hw_weigh.bits32,
526 	       port->dma_base + GMAC_TX_WEIGHTING_CTRL_0_REG);
527 	writel(sw_weigh.bits32,
528 	       port->dma_base + GMAC_TX_WEIGHTING_CTRL_1_REG);
529 
530 	port->rxq_order = DEFAULT_GMAC_RXQ_ORDER;
531 	port->txq_order = DEFAULT_GMAC_TXQ_ORDER;
532 	port->rx_coalesce_nsecs = DEFAULT_RX_COALESCE_NSECS;
533 
534 	/* Mark every quarter of the queue a packet for interrupt
535 	 * in order to be able to wake up the queue if it was stopped
536 	 */
537 	port->irq_every_tx_packets = 1 << (port->txq_order - 2);
538 
539 	return 0;
540 }
541 
542 static int gmac_setup_txqs(struct net_device *netdev)
543 {
544 	struct gemini_ethernet_port *port = netdev_priv(netdev);
545 	unsigned int n_txq = netdev->num_tx_queues;
546 	struct gemini_ethernet *geth = port->geth;
547 	size_t entries = 1 << port->txq_order;
548 	struct gmac_txq *txq = port->txq;
549 	struct gmac_txdesc *desc_ring;
550 	size_t len = n_txq * entries;
551 	struct sk_buff **skb_tab;
552 	void __iomem *rwptr_reg;
553 	unsigned int r;
554 	int i;
555 
556 	rwptr_reg = port->dma_base + GMAC_SW_TX_QUEUE0_PTR_REG;
557 
558 	skb_tab = kcalloc(len, sizeof(*skb_tab), GFP_KERNEL);
559 	if (!skb_tab)
560 		return -ENOMEM;
561 
562 	desc_ring = dma_alloc_coherent(geth->dev, len * sizeof(*desc_ring),
563 				       &port->txq_dma_base, GFP_KERNEL);
564 
565 	if (!desc_ring) {
566 		kfree(skb_tab);
567 		return -ENOMEM;
568 	}
569 
570 	if (port->txq_dma_base & ~DMA_Q_BASE_MASK) {
571 		dev_warn(geth->dev, "TX queue base is not aligned\n");
572 		dma_free_coherent(geth->dev, len * sizeof(*desc_ring),
573 				  desc_ring, port->txq_dma_base);
574 		kfree(skb_tab);
575 		return -ENOMEM;
576 	}
577 
578 	writel(port->txq_dma_base | port->txq_order,
579 	       port->dma_base + GMAC_SW_TX_QUEUE_BASE_REG);
580 
581 	for (i = 0; i < n_txq; i++) {
582 		txq->ring = desc_ring;
583 		txq->skb = skb_tab;
584 		txq->noirq_packets = 0;
585 
586 		r = readw(rwptr_reg);
587 		rwptr_reg += 2;
588 		writew(r, rwptr_reg);
589 		rwptr_reg += 2;
590 		txq->cptr = r;
591 
592 		txq++;
593 		desc_ring += entries;
594 		skb_tab += entries;
595 	}
596 
597 	return 0;
598 }
599 
600 static void gmac_clean_txq(struct net_device *netdev, struct gmac_txq *txq,
601 			   unsigned int r)
602 {
603 	struct gemini_ethernet_port *port = netdev_priv(netdev);
604 	unsigned int m = (1 << port->txq_order) - 1;
605 	struct gemini_ethernet *geth = port->geth;
606 	unsigned int c = txq->cptr;
607 	union gmac_txdesc_0 word0;
608 	union gmac_txdesc_1 word1;
609 	unsigned int hwchksum = 0;
610 	unsigned long bytes = 0;
611 	struct gmac_txdesc *txd;
612 	unsigned short nfrags;
613 	unsigned int errs = 0;
614 	unsigned int pkts = 0;
615 	unsigned int word3;
616 	dma_addr_t mapping;
617 
618 	if (c == r)
619 		return;
620 
621 	while (c != r) {
622 		txd = txq->ring + c;
623 		word0 = txd->word0;
624 		word1 = txd->word1;
625 		mapping = txd->word2.buf_adr;
626 		word3 = txd->word3.bits32;
627 
628 		dma_unmap_single(geth->dev, mapping,
629 				 word0.bits.buffer_size, DMA_TO_DEVICE);
630 
631 		if (word3 & EOF_BIT)
632 			dev_kfree_skb(txq->skb[c]);
633 
634 		c++;
635 		c &= m;
636 
637 		if (!(word3 & SOF_BIT))
638 			continue;
639 
640 		if (!word0.bits.status_tx_ok) {
641 			errs++;
642 			continue;
643 		}
644 
645 		pkts++;
646 		bytes += txd->word1.bits.byte_count;
647 
648 		if (word1.bits32 & TSS_CHECKUM_ENABLE)
649 			hwchksum++;
650 
651 		nfrags = word0.bits.desc_count - 1;
652 		if (nfrags) {
653 			if (nfrags >= TX_MAX_FRAGS)
654 				nfrags = TX_MAX_FRAGS - 1;
655 
656 			u64_stats_update_begin(&port->tx_stats_syncp);
657 			port->tx_frag_stats[nfrags]++;
658 			u64_stats_update_end(&port->tx_stats_syncp);
659 		}
660 	}
661 
662 	u64_stats_update_begin(&port->ir_stats_syncp);
663 	port->stats.tx_errors += errs;
664 	port->stats.tx_packets += pkts;
665 	port->stats.tx_bytes += bytes;
666 	port->tx_hw_csummed += hwchksum;
667 	u64_stats_update_end(&port->ir_stats_syncp);
668 
669 	txq->cptr = c;
670 }
671 
672 static void gmac_cleanup_txqs(struct net_device *netdev)
673 {
674 	struct gemini_ethernet_port *port = netdev_priv(netdev);
675 	unsigned int n_txq = netdev->num_tx_queues;
676 	struct gemini_ethernet *geth = port->geth;
677 	void __iomem *rwptr_reg;
678 	unsigned int r, i;
679 
680 	rwptr_reg = port->dma_base + GMAC_SW_TX_QUEUE0_PTR_REG;
681 
682 	for (i = 0; i < n_txq; i++) {
683 		r = readw(rwptr_reg);
684 		rwptr_reg += 2;
685 		writew(r, rwptr_reg);
686 		rwptr_reg += 2;
687 
688 		gmac_clean_txq(netdev, port->txq + i, r);
689 	}
690 	writel(0, port->dma_base + GMAC_SW_TX_QUEUE_BASE_REG);
691 
692 	kfree(port->txq->skb);
693 	dma_free_coherent(geth->dev,
694 			  n_txq * sizeof(*port->txq->ring) << port->txq_order,
695 			  port->txq->ring, port->txq_dma_base);
696 }
697 
698 static int gmac_setup_rxq(struct net_device *netdev)
699 {
700 	struct gemini_ethernet_port *port = netdev_priv(netdev);
701 	struct gemini_ethernet *geth = port->geth;
702 	struct nontoe_qhdr __iomem *qhdr;
703 
704 	qhdr = geth->base + TOE_DEFAULT_Q_HDR_BASE(netdev->dev_id);
705 	port->rxq_rwptr = &qhdr->word1;
706 
707 	/* Remap a slew of memory to use for the RX queue */
708 	port->rxq_ring = dma_alloc_coherent(geth->dev,
709 				sizeof(*port->rxq_ring) << port->rxq_order,
710 				&port->rxq_dma_base, GFP_KERNEL);
711 	if (!port->rxq_ring)
712 		return -ENOMEM;
713 	if (port->rxq_dma_base & ~NONTOE_QHDR0_BASE_MASK) {
714 		dev_warn(geth->dev, "RX queue base is not aligned\n");
715 		return -ENOMEM;
716 	}
717 
718 	writel(port->rxq_dma_base | port->rxq_order, &qhdr->word0);
719 	writel(0, port->rxq_rwptr);
720 	return 0;
721 }
722 
723 static struct gmac_queue_page *
724 gmac_get_queue_page(struct gemini_ethernet *geth,
725 		    struct gemini_ethernet_port *port,
726 		    dma_addr_t addr)
727 {
728 	struct gmac_queue_page *gpage;
729 	dma_addr_t mapping;
730 	int i;
731 
732 	/* Only look for even pages */
733 	mapping = addr & PAGE_MASK;
734 
735 	if (!geth->freeq_pages) {
736 		dev_err(geth->dev, "try to get page with no page list\n");
737 		return NULL;
738 	}
739 
740 	/* Look up a ring buffer page from virtual mapping */
741 	for (i = 0; i < geth->num_freeq_pages; i++) {
742 		gpage = &geth->freeq_pages[i];
743 		if (gpage->mapping == mapping)
744 			return gpage;
745 	}
746 
747 	return NULL;
748 }
749 
750 static void gmac_cleanup_rxq(struct net_device *netdev)
751 {
752 	struct gemini_ethernet_port *port = netdev_priv(netdev);
753 	struct gemini_ethernet *geth = port->geth;
754 	struct gmac_rxdesc *rxd = port->rxq_ring;
755 	static struct gmac_queue_page *gpage;
756 	struct nontoe_qhdr __iomem *qhdr;
757 	void __iomem *dma_reg;
758 	void __iomem *ptr_reg;
759 	dma_addr_t mapping;
760 	union dma_rwptr rw;
761 	unsigned int r, w;
762 
763 	qhdr = geth->base +
764 		TOE_DEFAULT_Q_HDR_BASE(netdev->dev_id);
765 	dma_reg = &qhdr->word0;
766 	ptr_reg = &qhdr->word1;
767 
768 	rw.bits32 = readl(ptr_reg);
769 	r = rw.bits.rptr;
770 	w = rw.bits.wptr;
771 	writew(r, ptr_reg + 2);
772 
773 	writel(0, dma_reg);
774 
775 	/* Loop from read pointer to write pointer of the RX queue
776 	 * and free up all pages by the queue.
777 	 */
778 	while (r != w) {
779 		mapping = rxd[r].word2.buf_adr;
780 		r++;
781 		r &= ((1 << port->rxq_order) - 1);
782 
783 		if (!mapping)
784 			continue;
785 
786 		/* Freeq pointers are one page off */
787 		gpage = gmac_get_queue_page(geth, port, mapping + PAGE_SIZE);
788 		if (!gpage) {
789 			dev_err(geth->dev, "could not find page\n");
790 			continue;
791 		}
792 		/* Release the RX queue reference to the page */
793 		put_page(gpage->page);
794 	}
795 
796 	dma_free_coherent(geth->dev, sizeof(*port->rxq_ring) << port->rxq_order,
797 			  port->rxq_ring, port->rxq_dma_base);
798 }
799 
800 static struct page *geth_freeq_alloc_map_page(struct gemini_ethernet *geth,
801 					      int pn)
802 {
803 	struct gmac_rxdesc *freeq_entry;
804 	struct gmac_queue_page *gpage;
805 	unsigned int fpp_order;
806 	unsigned int frag_len;
807 	dma_addr_t mapping;
808 	struct page *page;
809 	int i;
810 
811 	/* First allocate and DMA map a single page */
812 	page = alloc_page(GFP_ATOMIC);
813 	if (!page)
814 		return NULL;
815 
816 	mapping = dma_map_single(geth->dev, page_address(page),
817 				 PAGE_SIZE, DMA_FROM_DEVICE);
818 	if (dma_mapping_error(geth->dev, mapping)) {
819 		put_page(page);
820 		return NULL;
821 	}
822 
823 	/* The assign the page mapping (physical address) to the buffer address
824 	 * in the hardware queue. PAGE_SHIFT on ARM is 12 (1 page is 4096 bytes,
825 	 * 4k), and the default RX frag order is 11 (fragments are up 20 2048
826 	 * bytes, 2k) so fpp_order (fragments per page order) is default 1. Thus
827 	 * each page normally needs two entries in the queue.
828 	 */
829 	frag_len = 1 << geth->freeq_frag_order; /* Usually 2048 */
830 	fpp_order = PAGE_SHIFT - geth->freeq_frag_order;
831 	freeq_entry = geth->freeq_ring + (pn << fpp_order);
832 	dev_dbg(geth->dev, "allocate page %d fragment length %d fragments per page %d, freeq entry %p\n",
833 		 pn, frag_len, (1 << fpp_order), freeq_entry);
834 	for (i = (1 << fpp_order); i > 0; i--) {
835 		freeq_entry->word2.buf_adr = mapping;
836 		freeq_entry++;
837 		mapping += frag_len;
838 	}
839 
840 	/* If the freeq entry already has a page mapped, then unmap it. */
841 	gpage = &geth->freeq_pages[pn];
842 	if (gpage->page) {
843 		mapping = geth->freeq_ring[pn << fpp_order].word2.buf_adr;
844 		dma_unmap_single(geth->dev, mapping, frag_len, DMA_FROM_DEVICE);
845 		/* This should be the last reference to the page so it gets
846 		 * released
847 		 */
848 		put_page(gpage->page);
849 	}
850 
851 	/* Then put our new mapping into the page table */
852 	dev_dbg(geth->dev, "page %d, DMA addr: %08x, page %p\n",
853 		pn, (unsigned int)mapping, page);
854 	gpage->mapping = mapping;
855 	gpage->page = page;
856 
857 	return page;
858 }
859 
860 /**
861  * geth_fill_freeq() - Fill the freeq with empty fragments to use
862  * @geth: the ethernet adapter
863  * @refill: whether to reset the queue by filling in all freeq entries or
864  * just refill it, usually the interrupt to refill the queue happens when
865  * the queue is half empty.
866  */
867 static unsigned int geth_fill_freeq(struct gemini_ethernet *geth, bool refill)
868 {
869 	unsigned int fpp_order = PAGE_SHIFT - geth->freeq_frag_order;
870 	unsigned int count = 0;
871 	unsigned int pn, epn;
872 	unsigned long flags;
873 	union dma_rwptr rw;
874 	unsigned int m_pn;
875 
876 	/* Mask for page */
877 	m_pn = (1 << (geth->freeq_order - fpp_order)) - 1;
878 
879 	spin_lock_irqsave(&geth->freeq_lock, flags);
880 
881 	rw.bits32 = readl(geth->base + GLOBAL_SWFQ_RWPTR_REG);
882 	pn = (refill ? rw.bits.wptr : rw.bits.rptr) >> fpp_order;
883 	epn = (rw.bits.rptr >> fpp_order) - 1;
884 	epn &= m_pn;
885 
886 	/* Loop over the freeq ring buffer entries */
887 	while (pn != epn) {
888 		struct gmac_queue_page *gpage;
889 		struct page *page;
890 
891 		gpage = &geth->freeq_pages[pn];
892 		page = gpage->page;
893 
894 		dev_dbg(geth->dev, "fill entry %d page ref count %d add %d refs\n",
895 			pn, page_ref_count(page), 1 << fpp_order);
896 
897 		if (page_ref_count(page) > 1) {
898 			unsigned int fl = (pn - epn) & m_pn;
899 
900 			if (fl > 64 >> fpp_order)
901 				break;
902 
903 			page = geth_freeq_alloc_map_page(geth, pn);
904 			if (!page)
905 				break;
906 		}
907 
908 		/* Add one reference per fragment in the page */
909 		page_ref_add(page, 1 << fpp_order);
910 		count += 1 << fpp_order;
911 		pn++;
912 		pn &= m_pn;
913 	}
914 
915 	writew(pn << fpp_order, geth->base + GLOBAL_SWFQ_RWPTR_REG + 2);
916 
917 	spin_unlock_irqrestore(&geth->freeq_lock, flags);
918 
919 	return count;
920 }
921 
922 static int geth_setup_freeq(struct gemini_ethernet *geth)
923 {
924 	unsigned int fpp_order = PAGE_SHIFT - geth->freeq_frag_order;
925 	unsigned int frag_len = 1 << geth->freeq_frag_order;
926 	unsigned int len = 1 << geth->freeq_order;
927 	unsigned int pages = len >> fpp_order;
928 	union queue_threshold qt;
929 	union dma_skb_size skbsz;
930 	unsigned int filled;
931 	unsigned int pn;
932 
933 	geth->freeq_ring = dma_alloc_coherent(geth->dev,
934 		sizeof(*geth->freeq_ring) << geth->freeq_order,
935 		&geth->freeq_dma_base, GFP_KERNEL);
936 	if (!geth->freeq_ring)
937 		return -ENOMEM;
938 	if (geth->freeq_dma_base & ~DMA_Q_BASE_MASK) {
939 		dev_warn(geth->dev, "queue ring base is not aligned\n");
940 		goto err_freeq;
941 	}
942 
943 	/* Allocate a mapping to page look-up index */
944 	geth->freeq_pages = kcalloc(pages, sizeof(*geth->freeq_pages),
945 				    GFP_KERNEL);
946 	if (!geth->freeq_pages)
947 		goto err_freeq;
948 	geth->num_freeq_pages = pages;
949 
950 	dev_info(geth->dev, "allocate %d pages for queue\n", pages);
951 	for (pn = 0; pn < pages; pn++)
952 		if (!geth_freeq_alloc_map_page(geth, pn))
953 			goto err_freeq_alloc;
954 
955 	filled = geth_fill_freeq(geth, false);
956 	if (!filled)
957 		goto err_freeq_alloc;
958 
959 	qt.bits32 = readl(geth->base + GLOBAL_QUEUE_THRESHOLD_REG);
960 	qt.bits.swfq_empty = 32;
961 	writel(qt.bits32, geth->base + GLOBAL_QUEUE_THRESHOLD_REG);
962 
963 	skbsz.bits.sw_skb_size = 1 << geth->freeq_frag_order;
964 	writel(skbsz.bits32, geth->base + GLOBAL_DMA_SKB_SIZE_REG);
965 	writel(geth->freeq_dma_base | geth->freeq_order,
966 	       geth->base + GLOBAL_SW_FREEQ_BASE_SIZE_REG);
967 
968 	return 0;
969 
970 err_freeq_alloc:
971 	while (pn > 0) {
972 		struct gmac_queue_page *gpage;
973 		dma_addr_t mapping;
974 
975 		--pn;
976 		mapping = geth->freeq_ring[pn << fpp_order].word2.buf_adr;
977 		dma_unmap_single(geth->dev, mapping, frag_len, DMA_FROM_DEVICE);
978 		gpage = &geth->freeq_pages[pn];
979 		put_page(gpage->page);
980 	}
981 
982 	kfree(geth->freeq_pages);
983 err_freeq:
984 	dma_free_coherent(geth->dev,
985 			  sizeof(*geth->freeq_ring) << geth->freeq_order,
986 			  geth->freeq_ring, geth->freeq_dma_base);
987 	geth->freeq_ring = NULL;
988 	return -ENOMEM;
989 }
990 
991 /**
992  * geth_cleanup_freeq() - cleanup the DMA mappings and free the queue
993  * @geth: the Gemini global ethernet state
994  */
995 static void geth_cleanup_freeq(struct gemini_ethernet *geth)
996 {
997 	unsigned int fpp_order = PAGE_SHIFT - geth->freeq_frag_order;
998 	unsigned int frag_len = 1 << geth->freeq_frag_order;
999 	unsigned int len = 1 << geth->freeq_order;
1000 	unsigned int pages = len >> fpp_order;
1001 	unsigned int pn;
1002 
1003 	writew(readw(geth->base + GLOBAL_SWFQ_RWPTR_REG),
1004 	       geth->base + GLOBAL_SWFQ_RWPTR_REG + 2);
1005 	writel(0, geth->base + GLOBAL_SW_FREEQ_BASE_SIZE_REG);
1006 
1007 	for (pn = 0; pn < pages; pn++) {
1008 		struct gmac_queue_page *gpage;
1009 		dma_addr_t mapping;
1010 
1011 		mapping = geth->freeq_ring[pn << fpp_order].word2.buf_adr;
1012 		dma_unmap_single(geth->dev, mapping, frag_len, DMA_FROM_DEVICE);
1013 
1014 		gpage = &geth->freeq_pages[pn];
1015 		while (page_ref_count(gpage->page) > 0)
1016 			put_page(gpage->page);
1017 	}
1018 
1019 	kfree(geth->freeq_pages);
1020 
1021 	dma_free_coherent(geth->dev,
1022 			  sizeof(*geth->freeq_ring) << geth->freeq_order,
1023 			  geth->freeq_ring, geth->freeq_dma_base);
1024 }
1025 
1026 /**
1027  * geth_resize_freeq() - resize the software queue depth
1028  * @port: the port requesting the change
1029  *
1030  * This gets called at least once during probe() so the device queue gets
1031  * "resized" from the hardware defaults. Since both ports/net devices share
1032  * the same hardware queue, some synchronization between the ports is
1033  * needed.
1034  */
1035 static int geth_resize_freeq(struct gemini_ethernet_port *port)
1036 {
1037 	struct gemini_ethernet *geth = port->geth;
1038 	struct net_device *netdev = port->netdev;
1039 	struct gemini_ethernet_port *other_port;
1040 	struct net_device *other_netdev;
1041 	unsigned int new_size = 0;
1042 	unsigned int new_order;
1043 	unsigned long flags;
1044 	u32 en;
1045 	int ret;
1046 
1047 	if (netdev->dev_id == 0)
1048 		other_netdev = geth->port1->netdev;
1049 	else
1050 		other_netdev = geth->port0->netdev;
1051 
1052 	if (other_netdev && netif_running(other_netdev))
1053 		return -EBUSY;
1054 
1055 	new_size = 1 << (port->rxq_order + 1);
1056 	netdev_dbg(netdev, "port %d size: %d order %d\n",
1057 		   netdev->dev_id,
1058 		   new_size,
1059 		   port->rxq_order);
1060 	if (other_netdev) {
1061 		other_port = netdev_priv(other_netdev);
1062 		new_size += 1 << (other_port->rxq_order + 1);
1063 		netdev_dbg(other_netdev, "port %d size: %d order %d\n",
1064 			   other_netdev->dev_id,
1065 			   (1 << (other_port->rxq_order + 1)),
1066 			   other_port->rxq_order);
1067 	}
1068 
1069 	new_order = min(15, ilog2(new_size - 1) + 1);
1070 	dev_dbg(geth->dev, "set shared queue to size %d order %d\n",
1071 		new_size, new_order);
1072 	if (geth->freeq_order == new_order)
1073 		return 0;
1074 
1075 	spin_lock_irqsave(&geth->irq_lock, flags);
1076 
1077 	/* Disable the software queue IRQs */
1078 	en = readl(geth->base + GLOBAL_INTERRUPT_ENABLE_4_REG);
1079 	en &= ~SWFQ_EMPTY_INT_BIT;
1080 	writel(en, geth->base + GLOBAL_INTERRUPT_ENABLE_4_REG);
1081 	spin_unlock_irqrestore(&geth->irq_lock, flags);
1082 
1083 	/* Drop the old queue */
1084 	if (geth->freeq_ring)
1085 		geth_cleanup_freeq(geth);
1086 
1087 	/* Allocate a new queue with the desired order */
1088 	geth->freeq_order = new_order;
1089 	ret = geth_setup_freeq(geth);
1090 
1091 	/* Restart the interrupts - NOTE if this is the first resize
1092 	 * after probe(), this is where the interrupts get turned on
1093 	 * in the first place.
1094 	 */
1095 	spin_lock_irqsave(&geth->irq_lock, flags);
1096 	en |= SWFQ_EMPTY_INT_BIT;
1097 	writel(en, geth->base + GLOBAL_INTERRUPT_ENABLE_4_REG);
1098 	spin_unlock_irqrestore(&geth->irq_lock, flags);
1099 
1100 	return ret;
1101 }
1102 
1103 static void gmac_tx_irq_enable(struct net_device *netdev,
1104 			       unsigned int txq, int en)
1105 {
1106 	struct gemini_ethernet_port *port = netdev_priv(netdev);
1107 	struct gemini_ethernet *geth = port->geth;
1108 	u32 val, mask;
1109 
1110 	netdev_dbg(netdev, "%s device %d\n", __func__, netdev->dev_id);
1111 
1112 	mask = GMAC0_IRQ0_TXQ0_INTS << (6 * netdev->dev_id + txq);
1113 
1114 	if (en)
1115 		writel(mask, geth->base + GLOBAL_INTERRUPT_STATUS_0_REG);
1116 
1117 	val = readl(geth->base + GLOBAL_INTERRUPT_ENABLE_0_REG);
1118 	val = en ? val | mask : val & ~mask;
1119 	writel(val, geth->base + GLOBAL_INTERRUPT_ENABLE_0_REG);
1120 }
1121 
1122 static void gmac_tx_irq(struct net_device *netdev, unsigned int txq_num)
1123 {
1124 	struct netdev_queue *ntxq = netdev_get_tx_queue(netdev, txq_num);
1125 
1126 	gmac_tx_irq_enable(netdev, txq_num, 0);
1127 	netif_tx_wake_queue(ntxq);
1128 }
1129 
1130 static int gmac_map_tx_bufs(struct net_device *netdev, struct sk_buff *skb,
1131 			    struct gmac_txq *txq, unsigned short *desc)
1132 {
1133 	struct gemini_ethernet_port *port = netdev_priv(netdev);
1134 	struct skb_shared_info *skb_si =  skb_shinfo(skb);
1135 	unsigned short m = (1 << port->txq_order) - 1;
1136 	short frag, last_frag = skb_si->nr_frags - 1;
1137 	struct gemini_ethernet *geth = port->geth;
1138 	unsigned int word1, word3, buflen;
1139 	unsigned short w = *desc;
1140 	struct gmac_txdesc *txd;
1141 	skb_frag_t *skb_frag;
1142 	dma_addr_t mapping;
1143 	unsigned short mtu;
1144 	void *buffer;
1145 
1146 	mtu  = ETH_HLEN;
1147 	mtu += netdev->mtu;
1148 	if (skb->protocol == htons(ETH_P_8021Q))
1149 		mtu += VLAN_HLEN;
1150 
1151 	word1 = skb->len;
1152 	word3 = SOF_BIT;
1153 
1154 	if (word1 > mtu) {
1155 		word1 |= TSS_MTU_ENABLE_BIT;
1156 		word3 |= mtu;
1157 	}
1158 
1159 	if (skb->ip_summed != CHECKSUM_NONE) {
1160 		int tcp = 0;
1161 
1162 		if (skb->protocol == htons(ETH_P_IP)) {
1163 			word1 |= TSS_IP_CHKSUM_BIT;
1164 			tcp = ip_hdr(skb)->protocol == IPPROTO_TCP;
1165 		} else { /* IPv6 */
1166 			word1 |= TSS_IPV6_ENABLE_BIT;
1167 			tcp = ipv6_hdr(skb)->nexthdr == IPPROTO_TCP;
1168 		}
1169 
1170 		word1 |= tcp ? TSS_TCP_CHKSUM_BIT : TSS_UDP_CHKSUM_BIT;
1171 	}
1172 
1173 	frag = -1;
1174 	while (frag <= last_frag) {
1175 		if (frag == -1) {
1176 			buffer = skb->data;
1177 			buflen = skb_headlen(skb);
1178 		} else {
1179 			skb_frag = skb_si->frags + frag;
1180 			buffer = skb_frag_address(skb_frag);
1181 			buflen = skb_frag_size(skb_frag);
1182 		}
1183 
1184 		if (frag == last_frag) {
1185 			word3 |= EOF_BIT;
1186 			txq->skb[w] = skb;
1187 		}
1188 
1189 		mapping = dma_map_single(geth->dev, buffer, buflen,
1190 					 DMA_TO_DEVICE);
1191 		if (dma_mapping_error(geth->dev, mapping))
1192 			goto map_error;
1193 
1194 		txd = txq->ring + w;
1195 		txd->word0.bits32 = buflen;
1196 		txd->word1.bits32 = word1;
1197 		txd->word2.buf_adr = mapping;
1198 		txd->word3.bits32 = word3;
1199 
1200 		word3 &= MTU_SIZE_BIT_MASK;
1201 		w++;
1202 		w &= m;
1203 		frag++;
1204 	}
1205 
1206 	*desc = w;
1207 	return 0;
1208 
1209 map_error:
1210 	while (w != *desc) {
1211 		w--;
1212 		w &= m;
1213 
1214 		dma_unmap_page(geth->dev, txq->ring[w].word2.buf_adr,
1215 			       txq->ring[w].word0.bits.buffer_size,
1216 			       DMA_TO_DEVICE);
1217 	}
1218 	return -ENOMEM;
1219 }
1220 
1221 static netdev_tx_t gmac_start_xmit(struct sk_buff *skb,
1222 				   struct net_device *netdev)
1223 {
1224 	struct gemini_ethernet_port *port = netdev_priv(netdev);
1225 	unsigned short m = (1 << port->txq_order) - 1;
1226 	struct netdev_queue *ntxq;
1227 	unsigned short r, w, d;
1228 	void __iomem *ptr_reg;
1229 	struct gmac_txq *txq;
1230 	int txq_num, nfrags;
1231 	union dma_rwptr rw;
1232 
1233 	if (skb->len >= 0x10000)
1234 		goto out_drop_free;
1235 
1236 	txq_num = skb_get_queue_mapping(skb);
1237 	ptr_reg = port->dma_base + GMAC_SW_TX_QUEUE_PTR_REG(txq_num);
1238 	txq = &port->txq[txq_num];
1239 	ntxq = netdev_get_tx_queue(netdev, txq_num);
1240 	nfrags = skb_shinfo(skb)->nr_frags;
1241 
1242 	rw.bits32 = readl(ptr_reg);
1243 	r = rw.bits.rptr;
1244 	w = rw.bits.wptr;
1245 
1246 	d = txq->cptr - w - 1;
1247 	d &= m;
1248 
1249 	if (d < nfrags + 2) {
1250 		gmac_clean_txq(netdev, txq, r);
1251 		d = txq->cptr - w - 1;
1252 		d &= m;
1253 
1254 		if (d < nfrags + 2) {
1255 			netif_tx_stop_queue(ntxq);
1256 
1257 			d = txq->cptr + nfrags + 16;
1258 			d &= m;
1259 			txq->ring[d].word3.bits.eofie = 1;
1260 			gmac_tx_irq_enable(netdev, txq_num, 1);
1261 
1262 			u64_stats_update_begin(&port->tx_stats_syncp);
1263 			netdev->stats.tx_fifo_errors++;
1264 			u64_stats_update_end(&port->tx_stats_syncp);
1265 			return NETDEV_TX_BUSY;
1266 		}
1267 	}
1268 
1269 	if (gmac_map_tx_bufs(netdev, skb, txq, &w)) {
1270 		if (skb_linearize(skb))
1271 			goto out_drop;
1272 
1273 		u64_stats_update_begin(&port->tx_stats_syncp);
1274 		port->tx_frags_linearized++;
1275 		u64_stats_update_end(&port->tx_stats_syncp);
1276 
1277 		if (gmac_map_tx_bufs(netdev, skb, txq, &w))
1278 			goto out_drop_free;
1279 	}
1280 
1281 	writew(w, ptr_reg + 2);
1282 
1283 	gmac_clean_txq(netdev, txq, r);
1284 	return NETDEV_TX_OK;
1285 
1286 out_drop_free:
1287 	dev_kfree_skb(skb);
1288 out_drop:
1289 	u64_stats_update_begin(&port->tx_stats_syncp);
1290 	port->stats.tx_dropped++;
1291 	u64_stats_update_end(&port->tx_stats_syncp);
1292 	return NETDEV_TX_OK;
1293 }
1294 
1295 static void gmac_tx_timeout(struct net_device *netdev, unsigned int txqueue)
1296 {
1297 	netdev_err(netdev, "Tx timeout\n");
1298 	gmac_dump_dma_state(netdev);
1299 }
1300 
1301 static void gmac_enable_irq(struct net_device *netdev, int enable)
1302 {
1303 	struct gemini_ethernet_port *port = netdev_priv(netdev);
1304 	struct gemini_ethernet *geth = port->geth;
1305 	unsigned long flags;
1306 	u32 val, mask;
1307 
1308 	netdev_dbg(netdev, "%s device %d %s\n", __func__,
1309 		   netdev->dev_id, enable ? "enable" : "disable");
1310 	spin_lock_irqsave(&geth->irq_lock, flags);
1311 
1312 	mask = GMAC0_IRQ0_2 << (netdev->dev_id * 2);
1313 	val = readl(geth->base + GLOBAL_INTERRUPT_ENABLE_0_REG);
1314 	val = enable ? (val | mask) : (val & ~mask);
1315 	writel(val, geth->base + GLOBAL_INTERRUPT_ENABLE_0_REG);
1316 
1317 	mask = DEFAULT_Q0_INT_BIT << netdev->dev_id;
1318 	val = readl(geth->base + GLOBAL_INTERRUPT_ENABLE_1_REG);
1319 	val = enable ? (val | mask) : (val & ~mask);
1320 	writel(val, geth->base + GLOBAL_INTERRUPT_ENABLE_1_REG);
1321 
1322 	mask = GMAC0_IRQ4_8 << (netdev->dev_id * 8);
1323 	val = readl(geth->base + GLOBAL_INTERRUPT_ENABLE_4_REG);
1324 	val = enable ? (val | mask) : (val & ~mask);
1325 	writel(val, geth->base + GLOBAL_INTERRUPT_ENABLE_4_REG);
1326 
1327 	spin_unlock_irqrestore(&geth->irq_lock, flags);
1328 }
1329 
1330 static void gmac_enable_rx_irq(struct net_device *netdev, int enable)
1331 {
1332 	struct gemini_ethernet_port *port = netdev_priv(netdev);
1333 	struct gemini_ethernet *geth = port->geth;
1334 	unsigned long flags;
1335 	u32 val, mask;
1336 
1337 	netdev_dbg(netdev, "%s device %d %s\n", __func__, netdev->dev_id,
1338 		   enable ? "enable" : "disable");
1339 	spin_lock_irqsave(&geth->irq_lock, flags);
1340 	mask = DEFAULT_Q0_INT_BIT << netdev->dev_id;
1341 
1342 	val = readl(geth->base + GLOBAL_INTERRUPT_ENABLE_1_REG);
1343 	val = enable ? (val | mask) : (val & ~mask);
1344 	writel(val, geth->base + GLOBAL_INTERRUPT_ENABLE_1_REG);
1345 
1346 	spin_unlock_irqrestore(&geth->irq_lock, flags);
1347 }
1348 
1349 static struct sk_buff *gmac_skb_if_good_frame(struct gemini_ethernet_port *port,
1350 					      union gmac_rxdesc_0 word0,
1351 					      unsigned int frame_len)
1352 {
1353 	unsigned int rx_csum = word0.bits.chksum_status;
1354 	unsigned int rx_status = word0.bits.status;
1355 	struct sk_buff *skb = NULL;
1356 
1357 	port->rx_stats[rx_status]++;
1358 	port->rx_csum_stats[rx_csum]++;
1359 
1360 	if (word0.bits.derr || word0.bits.perr ||
1361 	    rx_status || frame_len < ETH_ZLEN ||
1362 	    rx_csum >= RX_CHKSUM_IP_ERR_UNKNOWN) {
1363 		port->stats.rx_errors++;
1364 
1365 		if (frame_len < ETH_ZLEN || RX_ERROR_LENGTH(rx_status))
1366 			port->stats.rx_length_errors++;
1367 		if (RX_ERROR_OVER(rx_status))
1368 			port->stats.rx_over_errors++;
1369 		if (RX_ERROR_CRC(rx_status))
1370 			port->stats.rx_crc_errors++;
1371 		if (RX_ERROR_FRAME(rx_status))
1372 			port->stats.rx_frame_errors++;
1373 		return NULL;
1374 	}
1375 
1376 	skb = napi_get_frags(&port->napi);
1377 	if (!skb)
1378 		goto update_exit;
1379 
1380 	if (rx_csum == RX_CHKSUM_IP_UDP_TCP_OK)
1381 		skb->ip_summed = CHECKSUM_UNNECESSARY;
1382 
1383 update_exit:
1384 	port->stats.rx_bytes += frame_len;
1385 	port->stats.rx_packets++;
1386 	return skb;
1387 }
1388 
1389 static unsigned int gmac_rx(struct net_device *netdev, unsigned int budget)
1390 {
1391 	struct gemini_ethernet_port *port = netdev_priv(netdev);
1392 	unsigned short m = (1 << port->rxq_order) - 1;
1393 	struct gemini_ethernet *geth = port->geth;
1394 	void __iomem *ptr_reg = port->rxq_rwptr;
1395 	unsigned int frame_len, frag_len;
1396 	struct gmac_rxdesc *rx = NULL;
1397 	struct gmac_queue_page *gpage;
1398 	static struct sk_buff *skb;
1399 	union gmac_rxdesc_0 word0;
1400 	union gmac_rxdesc_1 word1;
1401 	union gmac_rxdesc_3 word3;
1402 	struct page *page = NULL;
1403 	unsigned int page_offs;
1404 	unsigned short r, w;
1405 	union dma_rwptr rw;
1406 	dma_addr_t mapping;
1407 	int frag_nr = 0;
1408 
1409 	rw.bits32 = readl(ptr_reg);
1410 	/* Reset interrupt as all packages until here are taken into account */
1411 	writel(DEFAULT_Q0_INT_BIT << netdev->dev_id,
1412 	       geth->base + GLOBAL_INTERRUPT_STATUS_1_REG);
1413 	r = rw.bits.rptr;
1414 	w = rw.bits.wptr;
1415 
1416 	while (budget && w != r) {
1417 		rx = port->rxq_ring + r;
1418 		word0 = rx->word0;
1419 		word1 = rx->word1;
1420 		mapping = rx->word2.buf_adr;
1421 		word3 = rx->word3;
1422 
1423 		r++;
1424 		r &= m;
1425 
1426 		frag_len = word0.bits.buffer_size;
1427 		frame_len = word1.bits.byte_count;
1428 		page_offs = mapping & ~PAGE_MASK;
1429 
1430 		if (!mapping) {
1431 			netdev_err(netdev,
1432 				   "rxq[%u]: HW BUG: zero DMA desc\n", r);
1433 			goto err_drop;
1434 		}
1435 
1436 		/* Freeq pointers are one page off */
1437 		gpage = gmac_get_queue_page(geth, port, mapping + PAGE_SIZE);
1438 		if (!gpage) {
1439 			dev_err(geth->dev, "could not find mapping\n");
1440 			continue;
1441 		}
1442 		page = gpage->page;
1443 
1444 		if (word3.bits32 & SOF_BIT) {
1445 			if (skb) {
1446 				napi_free_frags(&port->napi);
1447 				port->stats.rx_dropped++;
1448 			}
1449 
1450 			skb = gmac_skb_if_good_frame(port, word0, frame_len);
1451 			if (!skb)
1452 				goto err_drop;
1453 
1454 			page_offs += NET_IP_ALIGN;
1455 			frag_len -= NET_IP_ALIGN;
1456 			frag_nr = 0;
1457 
1458 		} else if (!skb) {
1459 			put_page(page);
1460 			continue;
1461 		}
1462 
1463 		if (word3.bits32 & EOF_BIT)
1464 			frag_len = frame_len - skb->len;
1465 
1466 		/* append page frag to skb */
1467 		if (frag_nr == MAX_SKB_FRAGS)
1468 			goto err_drop;
1469 
1470 		if (frag_len == 0)
1471 			netdev_err(netdev, "Received fragment with len = 0\n");
1472 
1473 		skb_fill_page_desc(skb, frag_nr, page, page_offs, frag_len);
1474 		skb->len += frag_len;
1475 		skb->data_len += frag_len;
1476 		skb->truesize += frag_len;
1477 		frag_nr++;
1478 
1479 		if (word3.bits32 & EOF_BIT) {
1480 			napi_gro_frags(&port->napi);
1481 			skb = NULL;
1482 			--budget;
1483 		}
1484 		continue;
1485 
1486 err_drop:
1487 		if (skb) {
1488 			napi_free_frags(&port->napi);
1489 			skb = NULL;
1490 		}
1491 
1492 		if (mapping)
1493 			put_page(page);
1494 
1495 		port->stats.rx_dropped++;
1496 	}
1497 
1498 	writew(r, ptr_reg);
1499 	return budget;
1500 }
1501 
1502 static int gmac_napi_poll(struct napi_struct *napi, int budget)
1503 {
1504 	struct gemini_ethernet_port *port = netdev_priv(napi->dev);
1505 	struct gemini_ethernet *geth = port->geth;
1506 	unsigned int freeq_threshold;
1507 	unsigned int received;
1508 
1509 	freeq_threshold = 1 << (geth->freeq_order - 1);
1510 	u64_stats_update_begin(&port->rx_stats_syncp);
1511 
1512 	received = gmac_rx(napi->dev, budget);
1513 	if (received < budget) {
1514 		napi_gro_flush(napi, false);
1515 		napi_complete_done(napi, received);
1516 		gmac_enable_rx_irq(napi->dev, 1);
1517 		++port->rx_napi_exits;
1518 	}
1519 
1520 	port->freeq_refill += (budget - received);
1521 	if (port->freeq_refill > freeq_threshold) {
1522 		port->freeq_refill -= freeq_threshold;
1523 		geth_fill_freeq(geth, true);
1524 	}
1525 
1526 	u64_stats_update_end(&port->rx_stats_syncp);
1527 	return received;
1528 }
1529 
1530 static void gmac_dump_dma_state(struct net_device *netdev)
1531 {
1532 	struct gemini_ethernet_port *port = netdev_priv(netdev);
1533 	struct gemini_ethernet *geth = port->geth;
1534 	void __iomem *ptr_reg;
1535 	u32 reg[5];
1536 
1537 	/* Interrupt status */
1538 	reg[0] = readl(geth->base + GLOBAL_INTERRUPT_STATUS_0_REG);
1539 	reg[1] = readl(geth->base + GLOBAL_INTERRUPT_STATUS_1_REG);
1540 	reg[2] = readl(geth->base + GLOBAL_INTERRUPT_STATUS_2_REG);
1541 	reg[3] = readl(geth->base + GLOBAL_INTERRUPT_STATUS_3_REG);
1542 	reg[4] = readl(geth->base + GLOBAL_INTERRUPT_STATUS_4_REG);
1543 	netdev_err(netdev, "IRQ status: 0x%08x 0x%08x 0x%08x 0x%08x 0x%08x\n",
1544 		   reg[0], reg[1], reg[2], reg[3], reg[4]);
1545 
1546 	/* Interrupt enable */
1547 	reg[0] = readl(geth->base + GLOBAL_INTERRUPT_ENABLE_0_REG);
1548 	reg[1] = readl(geth->base + GLOBAL_INTERRUPT_ENABLE_1_REG);
1549 	reg[2] = readl(geth->base + GLOBAL_INTERRUPT_ENABLE_2_REG);
1550 	reg[3] = readl(geth->base + GLOBAL_INTERRUPT_ENABLE_3_REG);
1551 	reg[4] = readl(geth->base + GLOBAL_INTERRUPT_ENABLE_4_REG);
1552 	netdev_err(netdev, "IRQ enable: 0x%08x 0x%08x 0x%08x 0x%08x 0x%08x\n",
1553 		   reg[0], reg[1], reg[2], reg[3], reg[4]);
1554 
1555 	/* RX DMA status */
1556 	reg[0] = readl(port->dma_base + GMAC_DMA_RX_FIRST_DESC_REG);
1557 	reg[1] = readl(port->dma_base + GMAC_DMA_RX_CURR_DESC_REG);
1558 	reg[2] = GET_RPTR(port->rxq_rwptr);
1559 	reg[3] = GET_WPTR(port->rxq_rwptr);
1560 	netdev_err(netdev, "RX DMA regs: 0x%08x 0x%08x, ptr: %u %u\n",
1561 		   reg[0], reg[1], reg[2], reg[3]);
1562 
1563 	reg[0] = readl(port->dma_base + GMAC_DMA_RX_DESC_WORD0_REG);
1564 	reg[1] = readl(port->dma_base + GMAC_DMA_RX_DESC_WORD1_REG);
1565 	reg[2] = readl(port->dma_base + GMAC_DMA_RX_DESC_WORD2_REG);
1566 	reg[3] = readl(port->dma_base + GMAC_DMA_RX_DESC_WORD3_REG);
1567 	netdev_err(netdev, "RX DMA descriptor: 0x%08x 0x%08x 0x%08x 0x%08x\n",
1568 		   reg[0], reg[1], reg[2], reg[3]);
1569 
1570 	/* TX DMA status */
1571 	ptr_reg = port->dma_base + GMAC_SW_TX_QUEUE0_PTR_REG;
1572 
1573 	reg[0] = readl(port->dma_base + GMAC_DMA_TX_FIRST_DESC_REG);
1574 	reg[1] = readl(port->dma_base + GMAC_DMA_TX_CURR_DESC_REG);
1575 	reg[2] = GET_RPTR(ptr_reg);
1576 	reg[3] = GET_WPTR(ptr_reg);
1577 	netdev_err(netdev, "TX DMA regs: 0x%08x 0x%08x, ptr: %u %u\n",
1578 		   reg[0], reg[1], reg[2], reg[3]);
1579 
1580 	reg[0] = readl(port->dma_base + GMAC_DMA_TX_DESC_WORD0_REG);
1581 	reg[1] = readl(port->dma_base + GMAC_DMA_TX_DESC_WORD1_REG);
1582 	reg[2] = readl(port->dma_base + GMAC_DMA_TX_DESC_WORD2_REG);
1583 	reg[3] = readl(port->dma_base + GMAC_DMA_TX_DESC_WORD3_REG);
1584 	netdev_err(netdev, "TX DMA descriptor: 0x%08x 0x%08x 0x%08x 0x%08x\n",
1585 		   reg[0], reg[1], reg[2], reg[3]);
1586 
1587 	/* FREE queues status */
1588 	ptr_reg = geth->base + GLOBAL_SWFQ_RWPTR_REG;
1589 
1590 	reg[0] = GET_RPTR(ptr_reg);
1591 	reg[1] = GET_WPTR(ptr_reg);
1592 
1593 	ptr_reg = geth->base + GLOBAL_HWFQ_RWPTR_REG;
1594 
1595 	reg[2] = GET_RPTR(ptr_reg);
1596 	reg[3] = GET_WPTR(ptr_reg);
1597 	netdev_err(netdev, "FQ SW ptr: %u %u, HW ptr: %u %u\n",
1598 		   reg[0], reg[1], reg[2], reg[3]);
1599 }
1600 
1601 static void gmac_update_hw_stats(struct net_device *netdev)
1602 {
1603 	struct gemini_ethernet_port *port = netdev_priv(netdev);
1604 	unsigned int rx_discards, rx_mcast, rx_bcast;
1605 	struct gemini_ethernet *geth = port->geth;
1606 	unsigned long flags;
1607 
1608 	spin_lock_irqsave(&geth->irq_lock, flags);
1609 	u64_stats_update_begin(&port->ir_stats_syncp);
1610 
1611 	rx_discards = readl(port->gmac_base + GMAC_IN_DISCARDS);
1612 	port->hw_stats[0] += rx_discards;
1613 	port->hw_stats[1] += readl(port->gmac_base + GMAC_IN_ERRORS);
1614 	rx_mcast = readl(port->gmac_base + GMAC_IN_MCAST);
1615 	port->hw_stats[2] += rx_mcast;
1616 	rx_bcast = readl(port->gmac_base + GMAC_IN_BCAST);
1617 	port->hw_stats[3] += rx_bcast;
1618 	port->hw_stats[4] += readl(port->gmac_base + GMAC_IN_MAC1);
1619 	port->hw_stats[5] += readl(port->gmac_base + GMAC_IN_MAC2);
1620 
1621 	port->stats.rx_missed_errors += rx_discards;
1622 	port->stats.multicast += rx_mcast;
1623 	port->stats.multicast += rx_bcast;
1624 
1625 	writel(GMAC0_MIB_INT_BIT << (netdev->dev_id * 8),
1626 	       geth->base + GLOBAL_INTERRUPT_STATUS_4_REG);
1627 
1628 	u64_stats_update_end(&port->ir_stats_syncp);
1629 	spin_unlock_irqrestore(&geth->irq_lock, flags);
1630 }
1631 
1632 /**
1633  * gmac_get_intr_flags() - get interrupt status flags for a port from
1634  * @netdev: the net device for the port to get flags from
1635  * @i: the interrupt status register 0..4
1636  */
1637 static u32 gmac_get_intr_flags(struct net_device *netdev, int i)
1638 {
1639 	struct gemini_ethernet_port *port = netdev_priv(netdev);
1640 	struct gemini_ethernet *geth = port->geth;
1641 	void __iomem *irqif_reg, *irqen_reg;
1642 	unsigned int offs, val;
1643 
1644 	/* Calculate the offset using the stride of the status registers */
1645 	offs = i * (GLOBAL_INTERRUPT_STATUS_1_REG -
1646 		    GLOBAL_INTERRUPT_STATUS_0_REG);
1647 
1648 	irqif_reg = geth->base + GLOBAL_INTERRUPT_STATUS_0_REG + offs;
1649 	irqen_reg = geth->base + GLOBAL_INTERRUPT_ENABLE_0_REG + offs;
1650 
1651 	val = readl(irqif_reg) & readl(irqen_reg);
1652 	return val;
1653 }
1654 
1655 static enum hrtimer_restart gmac_coalesce_delay_expired(struct hrtimer *timer)
1656 {
1657 	struct gemini_ethernet_port *port =
1658 		container_of(timer, struct gemini_ethernet_port,
1659 			     rx_coalesce_timer);
1660 
1661 	napi_schedule(&port->napi);
1662 	return HRTIMER_NORESTART;
1663 }
1664 
1665 static irqreturn_t gmac_irq(int irq, void *data)
1666 {
1667 	struct gemini_ethernet_port *port;
1668 	struct net_device *netdev = data;
1669 	struct gemini_ethernet *geth;
1670 	u32 val, orr = 0;
1671 
1672 	port = netdev_priv(netdev);
1673 	geth = port->geth;
1674 
1675 	val = gmac_get_intr_flags(netdev, 0);
1676 	orr |= val;
1677 
1678 	if (val & (GMAC0_IRQ0_2 << (netdev->dev_id * 2))) {
1679 		/* Oh, crap */
1680 		netdev_err(netdev, "hw failure/sw bug\n");
1681 		gmac_dump_dma_state(netdev);
1682 
1683 		/* don't know how to recover, just reduce losses */
1684 		gmac_enable_irq(netdev, 0);
1685 		return IRQ_HANDLED;
1686 	}
1687 
1688 	if (val & (GMAC0_IRQ0_TXQ0_INTS << (netdev->dev_id * 6)))
1689 		gmac_tx_irq(netdev, 0);
1690 
1691 	val = gmac_get_intr_flags(netdev, 1);
1692 	orr |= val;
1693 
1694 	if (val & (DEFAULT_Q0_INT_BIT << netdev->dev_id)) {
1695 		gmac_enable_rx_irq(netdev, 0);
1696 
1697 		if (!port->rx_coalesce_nsecs) {
1698 			napi_schedule(&port->napi);
1699 		} else {
1700 			ktime_t ktime;
1701 
1702 			ktime = ktime_set(0, port->rx_coalesce_nsecs);
1703 			hrtimer_start(&port->rx_coalesce_timer, ktime,
1704 				      HRTIMER_MODE_REL);
1705 		}
1706 	}
1707 
1708 	val = gmac_get_intr_flags(netdev, 4);
1709 	orr |= val;
1710 
1711 	if (val & (GMAC0_MIB_INT_BIT << (netdev->dev_id * 8)))
1712 		gmac_update_hw_stats(netdev);
1713 
1714 	if (val & (GMAC0_RX_OVERRUN_INT_BIT << (netdev->dev_id * 8))) {
1715 		writel(GMAC0_RXDERR_INT_BIT << (netdev->dev_id * 8),
1716 		       geth->base + GLOBAL_INTERRUPT_STATUS_4_REG);
1717 
1718 		spin_lock(&geth->irq_lock);
1719 		u64_stats_update_begin(&port->ir_stats_syncp);
1720 		++port->stats.rx_fifo_errors;
1721 		u64_stats_update_end(&port->ir_stats_syncp);
1722 		spin_unlock(&geth->irq_lock);
1723 	}
1724 
1725 	return orr ? IRQ_HANDLED : IRQ_NONE;
1726 }
1727 
1728 static void gmac_start_dma(struct gemini_ethernet_port *port)
1729 {
1730 	void __iomem *dma_ctrl_reg = port->dma_base + GMAC_DMA_CTRL_REG;
1731 	union gmac_dma_ctrl dma_ctrl;
1732 
1733 	dma_ctrl.bits32 = readl(dma_ctrl_reg);
1734 	dma_ctrl.bits.rd_enable = 1;
1735 	dma_ctrl.bits.td_enable = 1;
1736 	dma_ctrl.bits.loopback = 0;
1737 	dma_ctrl.bits.drop_small_ack = 0;
1738 	dma_ctrl.bits.rd_insert_bytes = NET_IP_ALIGN;
1739 	dma_ctrl.bits.rd_prot = HPROT_DATA_CACHE | HPROT_PRIVILIGED;
1740 	dma_ctrl.bits.rd_burst_size = HBURST_INCR8;
1741 	dma_ctrl.bits.rd_bus = HSIZE_8;
1742 	dma_ctrl.bits.td_prot = HPROT_DATA_CACHE;
1743 	dma_ctrl.bits.td_burst_size = HBURST_INCR8;
1744 	dma_ctrl.bits.td_bus = HSIZE_8;
1745 
1746 	writel(dma_ctrl.bits32, dma_ctrl_reg);
1747 }
1748 
1749 static void gmac_stop_dma(struct gemini_ethernet_port *port)
1750 {
1751 	void __iomem *dma_ctrl_reg = port->dma_base + GMAC_DMA_CTRL_REG;
1752 	union gmac_dma_ctrl dma_ctrl;
1753 
1754 	dma_ctrl.bits32 = readl(dma_ctrl_reg);
1755 	dma_ctrl.bits.rd_enable = 0;
1756 	dma_ctrl.bits.td_enable = 0;
1757 	writel(dma_ctrl.bits32, dma_ctrl_reg);
1758 }
1759 
1760 static int gmac_open(struct net_device *netdev)
1761 {
1762 	struct gemini_ethernet_port *port = netdev_priv(netdev);
1763 	int err;
1764 
1765 	err = request_irq(netdev->irq, gmac_irq,
1766 			  IRQF_SHARED, netdev->name, netdev);
1767 	if (err) {
1768 		netdev_err(netdev, "no IRQ\n");
1769 		return err;
1770 	}
1771 
1772 	netif_carrier_off(netdev);
1773 	phy_start(netdev->phydev);
1774 
1775 	err = geth_resize_freeq(port);
1776 	/* It's fine if it's just busy, the other port has set up
1777 	 * the freeq in that case.
1778 	 */
1779 	if (err && (err != -EBUSY)) {
1780 		netdev_err(netdev, "could not resize freeq\n");
1781 		goto err_stop_phy;
1782 	}
1783 
1784 	err = gmac_setup_rxq(netdev);
1785 	if (err) {
1786 		netdev_err(netdev, "could not setup RXQ\n");
1787 		goto err_stop_phy;
1788 	}
1789 
1790 	err = gmac_setup_txqs(netdev);
1791 	if (err) {
1792 		netdev_err(netdev, "could not setup TXQs\n");
1793 		gmac_cleanup_rxq(netdev);
1794 		goto err_stop_phy;
1795 	}
1796 
1797 	napi_enable(&port->napi);
1798 
1799 	gmac_start_dma(port);
1800 	gmac_enable_irq(netdev, 1);
1801 	gmac_enable_tx_rx(netdev);
1802 	netif_tx_start_all_queues(netdev);
1803 
1804 	hrtimer_init(&port->rx_coalesce_timer, CLOCK_MONOTONIC,
1805 		     HRTIMER_MODE_REL);
1806 	port->rx_coalesce_timer.function = &gmac_coalesce_delay_expired;
1807 
1808 	netdev_dbg(netdev, "opened\n");
1809 
1810 	return 0;
1811 
1812 err_stop_phy:
1813 	phy_stop(netdev->phydev);
1814 	free_irq(netdev->irq, netdev);
1815 	return err;
1816 }
1817 
1818 static int gmac_stop(struct net_device *netdev)
1819 {
1820 	struct gemini_ethernet_port *port = netdev_priv(netdev);
1821 
1822 	hrtimer_cancel(&port->rx_coalesce_timer);
1823 	netif_tx_stop_all_queues(netdev);
1824 	gmac_disable_tx_rx(netdev);
1825 	gmac_stop_dma(port);
1826 	napi_disable(&port->napi);
1827 
1828 	gmac_enable_irq(netdev, 0);
1829 	gmac_cleanup_rxq(netdev);
1830 	gmac_cleanup_txqs(netdev);
1831 
1832 	phy_stop(netdev->phydev);
1833 	free_irq(netdev->irq, netdev);
1834 
1835 	gmac_update_hw_stats(netdev);
1836 	return 0;
1837 }
1838 
1839 static void gmac_set_rx_mode(struct net_device *netdev)
1840 {
1841 	struct gemini_ethernet_port *port = netdev_priv(netdev);
1842 	union gmac_rx_fltr filter = { .bits = {
1843 		.broadcast = 1,
1844 		.multicast = 1,
1845 		.unicast = 1,
1846 	} };
1847 	struct netdev_hw_addr *ha;
1848 	unsigned int bit_nr;
1849 	u32 mc_filter[2];
1850 
1851 	mc_filter[1] = 0;
1852 	mc_filter[0] = 0;
1853 
1854 	if (netdev->flags & IFF_PROMISC) {
1855 		filter.bits.error = 1;
1856 		filter.bits.promiscuous = 1;
1857 		mc_filter[1] = ~0;
1858 		mc_filter[0] = ~0;
1859 	} else if (netdev->flags & IFF_ALLMULTI) {
1860 		mc_filter[1] = ~0;
1861 		mc_filter[0] = ~0;
1862 	} else {
1863 		netdev_for_each_mc_addr(ha, netdev) {
1864 			bit_nr = ~crc32_le(~0, ha->addr, ETH_ALEN) & 0x3f;
1865 			mc_filter[bit_nr >> 5] |= 1 << (bit_nr & 0x1f);
1866 		}
1867 	}
1868 
1869 	writel(mc_filter[0], port->gmac_base + GMAC_MCAST_FIL0);
1870 	writel(mc_filter[1], port->gmac_base + GMAC_MCAST_FIL1);
1871 	writel(filter.bits32, port->gmac_base + GMAC_RX_FLTR);
1872 }
1873 
1874 static void gmac_write_mac_address(struct net_device *netdev)
1875 {
1876 	struct gemini_ethernet_port *port = netdev_priv(netdev);
1877 	__le32 addr[3];
1878 
1879 	memset(addr, 0, sizeof(addr));
1880 	memcpy(addr, netdev->dev_addr, ETH_ALEN);
1881 
1882 	writel(le32_to_cpu(addr[0]), port->gmac_base + GMAC_STA_ADD0);
1883 	writel(le32_to_cpu(addr[1]), port->gmac_base + GMAC_STA_ADD1);
1884 	writel(le32_to_cpu(addr[2]), port->gmac_base + GMAC_STA_ADD2);
1885 }
1886 
1887 static int gmac_set_mac_address(struct net_device *netdev, void *addr)
1888 {
1889 	struct sockaddr *sa = addr;
1890 
1891 	memcpy(netdev->dev_addr, sa->sa_data, ETH_ALEN);
1892 	gmac_write_mac_address(netdev);
1893 
1894 	return 0;
1895 }
1896 
1897 static void gmac_clear_hw_stats(struct net_device *netdev)
1898 {
1899 	struct gemini_ethernet_port *port = netdev_priv(netdev);
1900 
1901 	readl(port->gmac_base + GMAC_IN_DISCARDS);
1902 	readl(port->gmac_base + GMAC_IN_ERRORS);
1903 	readl(port->gmac_base + GMAC_IN_MCAST);
1904 	readl(port->gmac_base + GMAC_IN_BCAST);
1905 	readl(port->gmac_base + GMAC_IN_MAC1);
1906 	readl(port->gmac_base + GMAC_IN_MAC2);
1907 }
1908 
1909 static void gmac_get_stats64(struct net_device *netdev,
1910 			     struct rtnl_link_stats64 *stats)
1911 {
1912 	struct gemini_ethernet_port *port = netdev_priv(netdev);
1913 	unsigned int start;
1914 
1915 	gmac_update_hw_stats(netdev);
1916 
1917 	/* Racing with RX NAPI */
1918 	do {
1919 		start = u64_stats_fetch_begin(&port->rx_stats_syncp);
1920 
1921 		stats->rx_packets = port->stats.rx_packets;
1922 		stats->rx_bytes = port->stats.rx_bytes;
1923 		stats->rx_errors = port->stats.rx_errors;
1924 		stats->rx_dropped = port->stats.rx_dropped;
1925 
1926 		stats->rx_length_errors = port->stats.rx_length_errors;
1927 		stats->rx_over_errors = port->stats.rx_over_errors;
1928 		stats->rx_crc_errors = port->stats.rx_crc_errors;
1929 		stats->rx_frame_errors = port->stats.rx_frame_errors;
1930 
1931 	} while (u64_stats_fetch_retry(&port->rx_stats_syncp, start));
1932 
1933 	/* Racing with MIB and TX completion interrupts */
1934 	do {
1935 		start = u64_stats_fetch_begin(&port->ir_stats_syncp);
1936 
1937 		stats->tx_errors = port->stats.tx_errors;
1938 		stats->tx_packets = port->stats.tx_packets;
1939 		stats->tx_bytes = port->stats.tx_bytes;
1940 
1941 		stats->multicast = port->stats.multicast;
1942 		stats->rx_missed_errors = port->stats.rx_missed_errors;
1943 		stats->rx_fifo_errors = port->stats.rx_fifo_errors;
1944 
1945 	} while (u64_stats_fetch_retry(&port->ir_stats_syncp, start));
1946 
1947 	/* Racing with hard_start_xmit */
1948 	do {
1949 		start = u64_stats_fetch_begin(&port->tx_stats_syncp);
1950 
1951 		stats->tx_dropped = port->stats.tx_dropped;
1952 
1953 	} while (u64_stats_fetch_retry(&port->tx_stats_syncp, start));
1954 
1955 	stats->rx_dropped += stats->rx_missed_errors;
1956 }
1957 
1958 static int gmac_change_mtu(struct net_device *netdev, int new_mtu)
1959 {
1960 	int max_len = gmac_pick_rx_max_len(new_mtu);
1961 
1962 	if (max_len < 0)
1963 		return -EINVAL;
1964 
1965 	gmac_disable_tx_rx(netdev);
1966 
1967 	netdev->mtu = new_mtu;
1968 	gmac_update_config0_reg(netdev, max_len << CONFIG0_MAXLEN_SHIFT,
1969 				CONFIG0_MAXLEN_MASK);
1970 
1971 	netdev_update_features(netdev);
1972 
1973 	gmac_enable_tx_rx(netdev);
1974 
1975 	return 0;
1976 }
1977 
1978 static netdev_features_t gmac_fix_features(struct net_device *netdev,
1979 					   netdev_features_t features)
1980 {
1981 	if (netdev->mtu + ETH_HLEN + VLAN_HLEN > MTU_SIZE_BIT_MASK)
1982 		features &= ~GMAC_OFFLOAD_FEATURES;
1983 
1984 	return features;
1985 }
1986 
1987 static int gmac_set_features(struct net_device *netdev,
1988 			     netdev_features_t features)
1989 {
1990 	struct gemini_ethernet_port *port = netdev_priv(netdev);
1991 	int enable = features & NETIF_F_RXCSUM;
1992 	unsigned long flags;
1993 	u32 reg;
1994 
1995 	spin_lock_irqsave(&port->config_lock, flags);
1996 
1997 	reg = readl(port->gmac_base + GMAC_CONFIG0);
1998 	reg = enable ? reg | CONFIG0_RX_CHKSUM : reg & ~CONFIG0_RX_CHKSUM;
1999 	writel(reg, port->gmac_base + GMAC_CONFIG0);
2000 
2001 	spin_unlock_irqrestore(&port->config_lock, flags);
2002 	return 0;
2003 }
2004 
2005 static int gmac_get_sset_count(struct net_device *netdev, int sset)
2006 {
2007 	return sset == ETH_SS_STATS ? GMAC_STATS_NUM : 0;
2008 }
2009 
2010 static void gmac_get_strings(struct net_device *netdev, u32 stringset, u8 *data)
2011 {
2012 	if (stringset != ETH_SS_STATS)
2013 		return;
2014 
2015 	memcpy(data, gmac_stats_strings, sizeof(gmac_stats_strings));
2016 }
2017 
2018 static void gmac_get_ethtool_stats(struct net_device *netdev,
2019 				   struct ethtool_stats *estats, u64 *values)
2020 {
2021 	struct gemini_ethernet_port *port = netdev_priv(netdev);
2022 	unsigned int start;
2023 	u64 *p;
2024 	int i;
2025 
2026 	gmac_update_hw_stats(netdev);
2027 
2028 	/* Racing with MIB interrupt */
2029 	do {
2030 		p = values;
2031 		start = u64_stats_fetch_begin(&port->ir_stats_syncp);
2032 
2033 		for (i = 0; i < RX_STATS_NUM; i++)
2034 			*p++ = port->hw_stats[i];
2035 
2036 	} while (u64_stats_fetch_retry(&port->ir_stats_syncp, start));
2037 	values = p;
2038 
2039 	/* Racing with RX NAPI */
2040 	do {
2041 		p = values;
2042 		start = u64_stats_fetch_begin(&port->rx_stats_syncp);
2043 
2044 		for (i = 0; i < RX_STATUS_NUM; i++)
2045 			*p++ = port->rx_stats[i];
2046 		for (i = 0; i < RX_CHKSUM_NUM; i++)
2047 			*p++ = port->rx_csum_stats[i];
2048 		*p++ = port->rx_napi_exits;
2049 
2050 	} while (u64_stats_fetch_retry(&port->rx_stats_syncp, start));
2051 	values = p;
2052 
2053 	/* Racing with TX start_xmit */
2054 	do {
2055 		p = values;
2056 		start = u64_stats_fetch_begin(&port->tx_stats_syncp);
2057 
2058 		for (i = 0; i < TX_MAX_FRAGS; i++) {
2059 			*values++ = port->tx_frag_stats[i];
2060 			port->tx_frag_stats[i] = 0;
2061 		}
2062 		*values++ = port->tx_frags_linearized;
2063 		*values++ = port->tx_hw_csummed;
2064 
2065 	} while (u64_stats_fetch_retry(&port->tx_stats_syncp, start));
2066 }
2067 
2068 static int gmac_get_ksettings(struct net_device *netdev,
2069 			      struct ethtool_link_ksettings *cmd)
2070 {
2071 	if (!netdev->phydev)
2072 		return -ENXIO;
2073 	phy_ethtool_ksettings_get(netdev->phydev, cmd);
2074 
2075 	return 0;
2076 }
2077 
2078 static int gmac_set_ksettings(struct net_device *netdev,
2079 			      const struct ethtool_link_ksettings *cmd)
2080 {
2081 	if (!netdev->phydev)
2082 		return -ENXIO;
2083 	return phy_ethtool_ksettings_set(netdev->phydev, cmd);
2084 }
2085 
2086 static int gmac_nway_reset(struct net_device *netdev)
2087 {
2088 	if (!netdev->phydev)
2089 		return -ENXIO;
2090 	return phy_start_aneg(netdev->phydev);
2091 }
2092 
2093 static void gmac_get_pauseparam(struct net_device *netdev,
2094 				struct ethtool_pauseparam *pparam)
2095 {
2096 	struct gemini_ethernet_port *port = netdev_priv(netdev);
2097 	union gmac_config0 config0;
2098 
2099 	config0.bits32 = readl(port->gmac_base + GMAC_CONFIG0);
2100 
2101 	pparam->rx_pause = config0.bits.rx_fc_en;
2102 	pparam->tx_pause = config0.bits.tx_fc_en;
2103 	pparam->autoneg = true;
2104 }
2105 
2106 static void gmac_get_ringparam(struct net_device *netdev,
2107 			       struct ethtool_ringparam *rp)
2108 {
2109 	struct gemini_ethernet_port *port = netdev_priv(netdev);
2110 	union gmac_config0 config0;
2111 
2112 	config0.bits32 = readl(port->gmac_base + GMAC_CONFIG0);
2113 
2114 	rp->rx_max_pending = 1 << 15;
2115 	rp->rx_mini_max_pending = 0;
2116 	rp->rx_jumbo_max_pending = 0;
2117 	rp->tx_max_pending = 1 << 15;
2118 
2119 	rp->rx_pending = 1 << port->rxq_order;
2120 	rp->rx_mini_pending = 0;
2121 	rp->rx_jumbo_pending = 0;
2122 	rp->tx_pending = 1 << port->txq_order;
2123 }
2124 
2125 static int gmac_set_ringparam(struct net_device *netdev,
2126 			      struct ethtool_ringparam *rp)
2127 {
2128 	struct gemini_ethernet_port *port = netdev_priv(netdev);
2129 	int err = 0;
2130 
2131 	if (netif_running(netdev))
2132 		return -EBUSY;
2133 
2134 	if (rp->rx_pending) {
2135 		port->rxq_order = min(15, ilog2(rp->rx_pending - 1) + 1);
2136 		err = geth_resize_freeq(port);
2137 	}
2138 	if (rp->tx_pending) {
2139 		port->txq_order = min(15, ilog2(rp->tx_pending - 1) + 1);
2140 		port->irq_every_tx_packets = 1 << (port->txq_order - 2);
2141 	}
2142 
2143 	return err;
2144 }
2145 
2146 static int gmac_get_coalesce(struct net_device *netdev,
2147 			     struct ethtool_coalesce *ecmd)
2148 {
2149 	struct gemini_ethernet_port *port = netdev_priv(netdev);
2150 
2151 	ecmd->rx_max_coalesced_frames = 1;
2152 	ecmd->tx_max_coalesced_frames = port->irq_every_tx_packets;
2153 	ecmd->rx_coalesce_usecs = port->rx_coalesce_nsecs / 1000;
2154 
2155 	return 0;
2156 }
2157 
2158 static int gmac_set_coalesce(struct net_device *netdev,
2159 			     struct ethtool_coalesce *ecmd)
2160 {
2161 	struct gemini_ethernet_port *port = netdev_priv(netdev);
2162 
2163 	if (ecmd->tx_max_coalesced_frames < 1)
2164 		return -EINVAL;
2165 	if (ecmd->tx_max_coalesced_frames >= 1 << port->txq_order)
2166 		return -EINVAL;
2167 
2168 	port->irq_every_tx_packets = ecmd->tx_max_coalesced_frames;
2169 	port->rx_coalesce_nsecs = ecmd->rx_coalesce_usecs * 1000;
2170 
2171 	return 0;
2172 }
2173 
2174 static u32 gmac_get_msglevel(struct net_device *netdev)
2175 {
2176 	struct gemini_ethernet_port *port = netdev_priv(netdev);
2177 
2178 	return port->msg_enable;
2179 }
2180 
2181 static void gmac_set_msglevel(struct net_device *netdev, u32 level)
2182 {
2183 	struct gemini_ethernet_port *port = netdev_priv(netdev);
2184 
2185 	port->msg_enable = level;
2186 }
2187 
2188 static void gmac_get_drvinfo(struct net_device *netdev,
2189 			     struct ethtool_drvinfo *info)
2190 {
2191 	strcpy(info->driver,  DRV_NAME);
2192 	strcpy(info->bus_info, netdev->dev_id ? "1" : "0");
2193 }
2194 
2195 static const struct net_device_ops gmac_351x_ops = {
2196 	.ndo_init		= gmac_init,
2197 	.ndo_open		= gmac_open,
2198 	.ndo_stop		= gmac_stop,
2199 	.ndo_start_xmit		= gmac_start_xmit,
2200 	.ndo_tx_timeout		= gmac_tx_timeout,
2201 	.ndo_set_rx_mode	= gmac_set_rx_mode,
2202 	.ndo_set_mac_address	= gmac_set_mac_address,
2203 	.ndo_get_stats64	= gmac_get_stats64,
2204 	.ndo_change_mtu		= gmac_change_mtu,
2205 	.ndo_fix_features	= gmac_fix_features,
2206 	.ndo_set_features	= gmac_set_features,
2207 };
2208 
2209 static const struct ethtool_ops gmac_351x_ethtool_ops = {
2210 	.supported_coalesce_params = ETHTOOL_COALESCE_RX_USECS |
2211 				     ETHTOOL_COALESCE_MAX_FRAMES,
2212 	.get_sset_count	= gmac_get_sset_count,
2213 	.get_strings	= gmac_get_strings,
2214 	.get_ethtool_stats = gmac_get_ethtool_stats,
2215 	.get_link	= ethtool_op_get_link,
2216 	.get_link_ksettings = gmac_get_ksettings,
2217 	.set_link_ksettings = gmac_set_ksettings,
2218 	.nway_reset	= gmac_nway_reset,
2219 	.get_pauseparam	= gmac_get_pauseparam,
2220 	.get_ringparam	= gmac_get_ringparam,
2221 	.set_ringparam	= gmac_set_ringparam,
2222 	.get_coalesce	= gmac_get_coalesce,
2223 	.set_coalesce	= gmac_set_coalesce,
2224 	.get_msglevel	= gmac_get_msglevel,
2225 	.set_msglevel	= gmac_set_msglevel,
2226 	.get_drvinfo	= gmac_get_drvinfo,
2227 };
2228 
2229 static irqreturn_t gemini_port_irq_thread(int irq, void *data)
2230 {
2231 	unsigned long irqmask = SWFQ_EMPTY_INT_BIT;
2232 	struct gemini_ethernet_port *port = data;
2233 	struct gemini_ethernet *geth;
2234 	unsigned long flags;
2235 
2236 	geth = port->geth;
2237 	/* The queue is half empty so refill it */
2238 	geth_fill_freeq(geth, true);
2239 
2240 	spin_lock_irqsave(&geth->irq_lock, flags);
2241 	/* ACK queue interrupt */
2242 	writel(irqmask, geth->base + GLOBAL_INTERRUPT_STATUS_4_REG);
2243 	/* Enable queue interrupt again */
2244 	irqmask |= readl(geth->base + GLOBAL_INTERRUPT_ENABLE_4_REG);
2245 	writel(irqmask, geth->base + GLOBAL_INTERRUPT_ENABLE_4_REG);
2246 	spin_unlock_irqrestore(&geth->irq_lock, flags);
2247 
2248 	return IRQ_HANDLED;
2249 }
2250 
2251 static irqreturn_t gemini_port_irq(int irq, void *data)
2252 {
2253 	struct gemini_ethernet_port *port = data;
2254 	struct gemini_ethernet *geth;
2255 	irqreturn_t ret = IRQ_NONE;
2256 	u32 val, en;
2257 
2258 	geth = port->geth;
2259 	spin_lock(&geth->irq_lock);
2260 
2261 	val = readl(geth->base + GLOBAL_INTERRUPT_STATUS_4_REG);
2262 	en = readl(geth->base + GLOBAL_INTERRUPT_ENABLE_4_REG);
2263 
2264 	if (val & en & SWFQ_EMPTY_INT_BIT) {
2265 		/* Disable the queue empty interrupt while we work on
2266 		 * processing the queue. Also disable overrun interrupts
2267 		 * as there is not much we can do about it here.
2268 		 */
2269 		en &= ~(SWFQ_EMPTY_INT_BIT | GMAC0_RX_OVERRUN_INT_BIT
2270 					   | GMAC1_RX_OVERRUN_INT_BIT);
2271 		writel(en, geth->base + GLOBAL_INTERRUPT_ENABLE_4_REG);
2272 		ret = IRQ_WAKE_THREAD;
2273 	}
2274 
2275 	spin_unlock(&geth->irq_lock);
2276 
2277 	return ret;
2278 }
2279 
2280 static void gemini_port_remove(struct gemini_ethernet_port *port)
2281 {
2282 	if (port->netdev) {
2283 		phy_disconnect(port->netdev->phydev);
2284 		unregister_netdev(port->netdev);
2285 	}
2286 	clk_disable_unprepare(port->pclk);
2287 	geth_cleanup_freeq(port->geth);
2288 }
2289 
2290 static void gemini_ethernet_init(struct gemini_ethernet *geth)
2291 {
2292 	/* Only do this once both ports are online */
2293 	if (geth->initialized)
2294 		return;
2295 	if (geth->port0 && geth->port1)
2296 		geth->initialized = true;
2297 	else
2298 		return;
2299 
2300 	writel(0, geth->base + GLOBAL_INTERRUPT_ENABLE_0_REG);
2301 	writel(0, geth->base + GLOBAL_INTERRUPT_ENABLE_1_REG);
2302 	writel(0, geth->base + GLOBAL_INTERRUPT_ENABLE_2_REG);
2303 	writel(0, geth->base + GLOBAL_INTERRUPT_ENABLE_3_REG);
2304 	writel(0, geth->base + GLOBAL_INTERRUPT_ENABLE_4_REG);
2305 
2306 	/* Interrupt config:
2307 	 *
2308 	 *	GMAC0 intr bits ------> int0 ----> eth0
2309 	 *	GMAC1 intr bits ------> int1 ----> eth1
2310 	 *	TOE intr -------------> int1 ----> eth1
2311 	 *	Classification Intr --> int0 ----> eth0
2312 	 *	Default Q0 -----------> int0 ----> eth0
2313 	 *	Default Q1 -----------> int1 ----> eth1
2314 	 *	FreeQ intr -----------> int1 ----> eth1
2315 	 */
2316 	writel(0xCCFC0FC0, geth->base + GLOBAL_INTERRUPT_SELECT_0_REG);
2317 	writel(0x00F00002, geth->base + GLOBAL_INTERRUPT_SELECT_1_REG);
2318 	writel(0xFFFFFFFF, geth->base + GLOBAL_INTERRUPT_SELECT_2_REG);
2319 	writel(0xFFFFFFFF, geth->base + GLOBAL_INTERRUPT_SELECT_3_REG);
2320 	writel(0xFF000003, geth->base + GLOBAL_INTERRUPT_SELECT_4_REG);
2321 
2322 	/* edge-triggered interrupts packed to level-triggered one... */
2323 	writel(~0, geth->base + GLOBAL_INTERRUPT_STATUS_0_REG);
2324 	writel(~0, geth->base + GLOBAL_INTERRUPT_STATUS_1_REG);
2325 	writel(~0, geth->base + GLOBAL_INTERRUPT_STATUS_2_REG);
2326 	writel(~0, geth->base + GLOBAL_INTERRUPT_STATUS_3_REG);
2327 	writel(~0, geth->base + GLOBAL_INTERRUPT_STATUS_4_REG);
2328 
2329 	/* Set up queue */
2330 	writel(0, geth->base + GLOBAL_SW_FREEQ_BASE_SIZE_REG);
2331 	writel(0, geth->base + GLOBAL_HW_FREEQ_BASE_SIZE_REG);
2332 	writel(0, geth->base + GLOBAL_SWFQ_RWPTR_REG);
2333 	writel(0, geth->base + GLOBAL_HWFQ_RWPTR_REG);
2334 
2335 	geth->freeq_frag_order = DEFAULT_RX_BUF_ORDER;
2336 	/* This makes the queue resize on probe() so that we
2337 	 * set up and enable the queue IRQ. FIXME: fragile.
2338 	 */
2339 	geth->freeq_order = 1;
2340 }
2341 
2342 static void gemini_port_save_mac_addr(struct gemini_ethernet_port *port)
2343 {
2344 	port->mac_addr[0] =
2345 		cpu_to_le32(readl(port->gmac_base + GMAC_STA_ADD0));
2346 	port->mac_addr[1] =
2347 		cpu_to_le32(readl(port->gmac_base + GMAC_STA_ADD1));
2348 	port->mac_addr[2] =
2349 		cpu_to_le32(readl(port->gmac_base + GMAC_STA_ADD2));
2350 }
2351 
2352 static int gemini_ethernet_port_probe(struct platform_device *pdev)
2353 {
2354 	char *port_names[2] = { "ethernet0", "ethernet1" };
2355 	struct gemini_ethernet_port *port;
2356 	struct device *dev = &pdev->dev;
2357 	struct gemini_ethernet *geth;
2358 	struct net_device *netdev;
2359 	struct resource *gmacres;
2360 	struct resource *dmares;
2361 	struct device *parent;
2362 	unsigned int id;
2363 	int irq;
2364 	int ret;
2365 
2366 	parent = dev->parent;
2367 	geth = dev_get_drvdata(parent);
2368 
2369 	if (!strcmp(dev_name(dev), "60008000.ethernet-port"))
2370 		id = 0;
2371 	else if (!strcmp(dev_name(dev), "6000c000.ethernet-port"))
2372 		id = 1;
2373 	else
2374 		return -ENODEV;
2375 
2376 	dev_info(dev, "probe %s ID %d\n", dev_name(dev), id);
2377 
2378 	netdev = devm_alloc_etherdev_mqs(dev, sizeof(*port), TX_QUEUE_NUM, TX_QUEUE_NUM);
2379 	if (!netdev) {
2380 		dev_err(dev, "Can't allocate ethernet device #%d\n", id);
2381 		return -ENOMEM;
2382 	}
2383 
2384 	port = netdev_priv(netdev);
2385 	SET_NETDEV_DEV(netdev, dev);
2386 	port->netdev = netdev;
2387 	port->id = id;
2388 	port->geth = geth;
2389 	port->dev = dev;
2390 	port->msg_enable = netif_msg_init(debug, DEFAULT_MSG_ENABLE);
2391 
2392 	/* DMA memory */
2393 	dmares = platform_get_resource(pdev, IORESOURCE_MEM, 0);
2394 	if (!dmares) {
2395 		dev_err(dev, "no DMA resource\n");
2396 		return -ENODEV;
2397 	}
2398 	port->dma_base = devm_ioremap_resource(dev, dmares);
2399 	if (IS_ERR(port->dma_base))
2400 		return PTR_ERR(port->dma_base);
2401 
2402 	/* GMAC config memory */
2403 	gmacres = platform_get_resource(pdev, IORESOURCE_MEM, 1);
2404 	if (!gmacres) {
2405 		dev_err(dev, "no GMAC resource\n");
2406 		return -ENODEV;
2407 	}
2408 	port->gmac_base = devm_ioremap_resource(dev, gmacres);
2409 	if (IS_ERR(port->gmac_base))
2410 		return PTR_ERR(port->gmac_base);
2411 
2412 	/* Interrupt */
2413 	irq = platform_get_irq(pdev, 0);
2414 	if (irq <= 0)
2415 		return irq ? irq : -ENODEV;
2416 	port->irq = irq;
2417 
2418 	/* Clock the port */
2419 	port->pclk = devm_clk_get(dev, "PCLK");
2420 	if (IS_ERR(port->pclk)) {
2421 		dev_err(dev, "no PCLK\n");
2422 		return PTR_ERR(port->pclk);
2423 	}
2424 	ret = clk_prepare_enable(port->pclk);
2425 	if (ret)
2426 		return ret;
2427 
2428 	/* Maybe there is a nice ethernet address we should use */
2429 	gemini_port_save_mac_addr(port);
2430 
2431 	/* Reset the port */
2432 	port->reset = devm_reset_control_get_exclusive(dev, NULL);
2433 	if (IS_ERR(port->reset)) {
2434 		dev_err(dev, "no reset\n");
2435 		ret = PTR_ERR(port->reset);
2436 		goto unprepare;
2437 	}
2438 	reset_control_reset(port->reset);
2439 	usleep_range(100, 500);
2440 
2441 	/* Assign pointer in the main state container */
2442 	if (!id)
2443 		geth->port0 = port;
2444 	else
2445 		geth->port1 = port;
2446 
2447 	/* This will just be done once both ports are up and reset */
2448 	gemini_ethernet_init(geth);
2449 
2450 	platform_set_drvdata(pdev, port);
2451 
2452 	/* Set up and register the netdev */
2453 	netdev->dev_id = port->id;
2454 	netdev->irq = irq;
2455 	netdev->netdev_ops = &gmac_351x_ops;
2456 	netdev->ethtool_ops = &gmac_351x_ethtool_ops;
2457 
2458 	spin_lock_init(&port->config_lock);
2459 	gmac_clear_hw_stats(netdev);
2460 
2461 	netdev->hw_features = GMAC_OFFLOAD_FEATURES;
2462 	netdev->features |= GMAC_OFFLOAD_FEATURES | NETIF_F_GRO;
2463 	/* We can handle jumbo frames up to 10236 bytes so, let's accept
2464 	 * payloads of 10236 bytes minus VLAN and ethernet header
2465 	 */
2466 	netdev->min_mtu = ETH_MIN_MTU;
2467 	netdev->max_mtu = 10236 - VLAN_ETH_HLEN;
2468 
2469 	port->freeq_refill = 0;
2470 	netif_napi_add(netdev, &port->napi, gmac_napi_poll,
2471 		       DEFAULT_NAPI_WEIGHT);
2472 
2473 	if (is_valid_ether_addr((void *)port->mac_addr)) {
2474 		memcpy(netdev->dev_addr, port->mac_addr, ETH_ALEN);
2475 	} else {
2476 		dev_dbg(dev, "ethernet address 0x%08x%08x%08x invalid\n",
2477 			port->mac_addr[0], port->mac_addr[1],
2478 			port->mac_addr[2]);
2479 		dev_info(dev, "using a random ethernet address\n");
2480 		eth_random_addr(netdev->dev_addr);
2481 	}
2482 	gmac_write_mac_address(netdev);
2483 
2484 	ret = devm_request_threaded_irq(port->dev,
2485 					port->irq,
2486 					gemini_port_irq,
2487 					gemini_port_irq_thread,
2488 					IRQF_SHARED,
2489 					port_names[port->id],
2490 					port);
2491 	if (ret)
2492 		goto unprepare;
2493 
2494 	ret = gmac_setup_phy(netdev);
2495 	if (ret) {
2496 		netdev_err(netdev,
2497 			   "PHY init failed\n");
2498 		goto unprepare;
2499 	}
2500 
2501 	ret = register_netdev(netdev);
2502 	if (ret)
2503 		goto unprepare;
2504 
2505 	netdev_info(netdev,
2506 		    "irq %d, DMA @ 0x%pap, GMAC @ 0x%pap\n",
2507 		    port->irq, &dmares->start,
2508 		    &gmacres->start);
2509 	return 0;
2510 
2511 unprepare:
2512 	clk_disable_unprepare(port->pclk);
2513 	return ret;
2514 }
2515 
2516 static int gemini_ethernet_port_remove(struct platform_device *pdev)
2517 {
2518 	struct gemini_ethernet_port *port = platform_get_drvdata(pdev);
2519 
2520 	gemini_port_remove(port);
2521 
2522 	return 0;
2523 }
2524 
2525 static const struct of_device_id gemini_ethernet_port_of_match[] = {
2526 	{
2527 		.compatible = "cortina,gemini-ethernet-port",
2528 	},
2529 	{},
2530 };
2531 MODULE_DEVICE_TABLE(of, gemini_ethernet_port_of_match);
2532 
2533 static struct platform_driver gemini_ethernet_port_driver = {
2534 	.driver = {
2535 		.name = "gemini-ethernet-port",
2536 		.of_match_table = of_match_ptr(gemini_ethernet_port_of_match),
2537 	},
2538 	.probe = gemini_ethernet_port_probe,
2539 	.remove = gemini_ethernet_port_remove,
2540 };
2541 
2542 static int gemini_ethernet_probe(struct platform_device *pdev)
2543 {
2544 	struct device *dev = &pdev->dev;
2545 	struct gemini_ethernet *geth;
2546 	unsigned int retry = 5;
2547 	struct resource *res;
2548 	u32 val;
2549 
2550 	/* Global registers */
2551 	geth = devm_kzalloc(dev, sizeof(*geth), GFP_KERNEL);
2552 	if (!geth)
2553 		return -ENOMEM;
2554 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
2555 	if (!res)
2556 		return -ENODEV;
2557 	geth->base = devm_ioremap_resource(dev, res);
2558 	if (IS_ERR(geth->base))
2559 		return PTR_ERR(geth->base);
2560 	geth->dev = dev;
2561 
2562 	/* Wait for ports to stabilize */
2563 	do {
2564 		udelay(2);
2565 		val = readl(geth->base + GLOBAL_TOE_VERSION_REG);
2566 		barrier();
2567 	} while (!val && --retry);
2568 	if (!retry) {
2569 		dev_err(dev, "failed to reset ethernet\n");
2570 		return -EIO;
2571 	}
2572 	dev_info(dev, "Ethernet device ID: 0x%03x, revision 0x%01x\n",
2573 		 (val >> 4) & 0xFFFU, val & 0xFU);
2574 
2575 	spin_lock_init(&geth->irq_lock);
2576 	spin_lock_init(&geth->freeq_lock);
2577 
2578 	/* The children will use this */
2579 	platform_set_drvdata(pdev, geth);
2580 
2581 	/* Spawn child devices for the two ports */
2582 	return devm_of_platform_populate(dev);
2583 }
2584 
2585 static int gemini_ethernet_remove(struct platform_device *pdev)
2586 {
2587 	struct gemini_ethernet *geth = platform_get_drvdata(pdev);
2588 
2589 	geth_cleanup_freeq(geth);
2590 	geth->initialized = false;
2591 
2592 	return 0;
2593 }
2594 
2595 static const struct of_device_id gemini_ethernet_of_match[] = {
2596 	{
2597 		.compatible = "cortina,gemini-ethernet",
2598 	},
2599 	{},
2600 };
2601 MODULE_DEVICE_TABLE(of, gemini_ethernet_of_match);
2602 
2603 static struct platform_driver gemini_ethernet_driver = {
2604 	.driver = {
2605 		.name = DRV_NAME,
2606 		.of_match_table = of_match_ptr(gemini_ethernet_of_match),
2607 	},
2608 	.probe = gemini_ethernet_probe,
2609 	.remove = gemini_ethernet_remove,
2610 };
2611 
2612 static int __init gemini_ethernet_module_init(void)
2613 {
2614 	int ret;
2615 
2616 	ret = platform_driver_register(&gemini_ethernet_port_driver);
2617 	if (ret)
2618 		return ret;
2619 
2620 	ret = platform_driver_register(&gemini_ethernet_driver);
2621 	if (ret) {
2622 		platform_driver_unregister(&gemini_ethernet_port_driver);
2623 		return ret;
2624 	}
2625 
2626 	return 0;
2627 }
2628 module_init(gemini_ethernet_module_init);
2629 
2630 static void __exit gemini_ethernet_module_exit(void)
2631 {
2632 	platform_driver_unregister(&gemini_ethernet_driver);
2633 	platform_driver_unregister(&gemini_ethernet_port_driver);
2634 }
2635 module_exit(gemini_ethernet_module_exit);
2636 
2637 MODULE_AUTHOR("Linus Walleij <linus.walleij@linaro.org>");
2638 MODULE_DESCRIPTION("StorLink SL351x (Gemini) ethernet driver");
2639 MODULE_LICENSE("GPL");
2640 MODULE_ALIAS("platform:" DRV_NAME);
2641