/drivers/net/ethernet/cadence/macb.c

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   1/*
   2 * Cadence MACB/GEM Ethernet Controller driver
   3 *
   4 * Copyright (C) 2004-2006 Atmel Corporation
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License version 2 as
   8 * published by the Free Software Foundation.
   9 */
  10
  11#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  12#include <linux/clk.h>
  13#include <linux/module.h>
  14#include <linux/moduleparam.h>
  15#include <linux/kernel.h>
  16#include <linux/types.h>
  17#include <linux/circ_buf.h>
  18#include <linux/slab.h>
  19#include <linux/init.h>
  20#include <linux/io.h>
  21#include <linux/gpio.h>
  22#include <linux/gpio/consumer.h>
  23#include <linux/interrupt.h>
  24#include <linux/netdevice.h>
  25#include <linux/etherdevice.h>
  26#include <linux/dma-mapping.h>
  27#include <linux/platform_data/macb.h>
  28#include <linux/platform_device.h>
  29#include <linux/phy.h>
  30#include <linux/of.h>
  31#include <linux/of_device.h>
  32#include <linux/of_gpio.h>
  33#include <linux/of_mdio.h>
  34#include <linux/of_net.h>
  35
  36#include "macb.h"
  37
  38#define MACB_RX_BUFFER_SIZE	128
  39#define RX_BUFFER_MULTIPLE	64  /* bytes */
  40#define RX_RING_SIZE		512 /* must be power of 2 */
  41#define RX_RING_BYTES		(sizeof(struct macb_dma_desc) * RX_RING_SIZE)
  42
  43#define TX_RING_SIZE		128 /* must be power of 2 */
  44#define TX_RING_BYTES		(sizeof(struct macb_dma_desc) * TX_RING_SIZE)
  45
  46/* level of occupied TX descriptors under which we wake up TX process */
  47#define MACB_TX_WAKEUP_THRESH	(3 * TX_RING_SIZE / 4)
  48
  49#define MACB_RX_INT_FLAGS	(MACB_BIT(RCOMP) | MACB_BIT(RXUBR)	\
  50				 | MACB_BIT(ISR_ROVR))
  51#define MACB_TX_ERR_FLAGS	(MACB_BIT(ISR_TUND)			\
  52					| MACB_BIT(ISR_RLE)		\
  53					| MACB_BIT(TXERR))
  54#define MACB_TX_INT_FLAGS	(MACB_TX_ERR_FLAGS | MACB_BIT(TCOMP))
  55
  56#define MACB_MAX_TX_LEN		((unsigned int)((1 << MACB_TX_FRMLEN_SIZE) - 1))
  57#define GEM_MAX_TX_LEN		((unsigned int)((1 << GEM_TX_FRMLEN_SIZE) - 1))
  58
  59#define GEM_MTU_MIN_SIZE	68
  60
  61#define MACB_WOL_HAS_MAGIC_PACKET	(0x1 << 0)
  62#define MACB_WOL_ENABLED		(0x1 << 1)
  63
  64/* Graceful stop timeouts in us. We should allow up to
  65 * 1 frame time (10 Mbits/s, full-duplex, ignoring collisions)
  66 */
  67#define MACB_HALT_TIMEOUT	1230
  68
  69/* Ring buffer accessors */
  70static unsigned int macb_tx_ring_wrap(unsigned int index)
  71{
  72	return index & (TX_RING_SIZE - 1);
  73}
  74
  75static struct macb_dma_desc *macb_tx_desc(struct macb_queue *queue,
  76					  unsigned int index)
  77{
  78	return &queue->tx_ring[macb_tx_ring_wrap(index)];
  79}
  80
  81static struct macb_tx_skb *macb_tx_skb(struct macb_queue *queue,
  82				       unsigned int index)
  83{
  84	return &queue->tx_skb[macb_tx_ring_wrap(index)];
  85}
  86
  87static dma_addr_t macb_tx_dma(struct macb_queue *queue, unsigned int index)
  88{
  89	dma_addr_t offset;
  90
  91	offset = macb_tx_ring_wrap(index) * sizeof(struct macb_dma_desc);
  92
  93	return queue->tx_ring_dma + offset;
  94}
  95
  96static unsigned int macb_rx_ring_wrap(unsigned int index)
  97{
  98	return index & (RX_RING_SIZE - 1);
  99}
 100
 101static struct macb_dma_desc *macb_rx_desc(struct macb *bp, unsigned int index)
 102{
 103	return &bp->rx_ring[macb_rx_ring_wrap(index)];
 104}
 105
 106static void *macb_rx_buffer(struct macb *bp, unsigned int index)
 107{
 108	return bp->rx_buffers + bp->rx_buffer_size * macb_rx_ring_wrap(index);
 109}
 110
 111/* I/O accessors */
 112static u32 hw_readl_native(struct macb *bp, int offset)
 113{
 114	return __raw_readl(bp->regs + offset);
 115}
 116
 117static void hw_writel_native(struct macb *bp, int offset, u32 value)
 118{
 119	__raw_writel(value, bp->regs + offset);
 120}
 121
 122static u32 hw_readl(struct macb *bp, int offset)
 123{
 124	return readl_relaxed(bp->regs + offset);
 125}
 126
 127static void hw_writel(struct macb *bp, int offset, u32 value)
 128{
 129	writel_relaxed(value, bp->regs + offset);
 130}
 131
 132/* Find the CPU endianness by using the loopback bit of NCR register. When the
 133 * CPU is in big endian we need to program swapped mode for management
 134 * descriptor access.
 135 */
 136static bool hw_is_native_io(void __iomem *addr)
 137{
 138	u32 value = MACB_BIT(LLB);
 139
 140	__raw_writel(value, addr + MACB_NCR);
 141	value = __raw_readl(addr + MACB_NCR);
 142
 143	/* Write 0 back to disable everything */
 144	__raw_writel(0, addr + MACB_NCR);
 145
 146	return value == MACB_BIT(LLB);
 147}
 148
 149static bool hw_is_gem(void __iomem *addr, bool native_io)
 150{
 151	u32 id;
 152
 153	if (native_io)
 154		id = __raw_readl(addr + MACB_MID);
 155	else
 156		id = readl_relaxed(addr + MACB_MID);
 157
 158	return MACB_BFEXT(IDNUM, id) >= 0x2;
 159}
 160
 161static void macb_set_hwaddr(struct macb *bp)
 162{
 163	u32 bottom;
 164	u16 top;
 165
 166	bottom = cpu_to_le32(*((u32 *)bp->dev->dev_addr));
 167	macb_or_gem_writel(bp, SA1B, bottom);
 168	top = cpu_to_le16(*((u16 *)(bp->dev->dev_addr + 4)));
 169	macb_or_gem_writel(bp, SA1T, top);
 170
 171	/* Clear unused address register sets */
 172	macb_or_gem_writel(bp, SA2B, 0);
 173	macb_or_gem_writel(bp, SA2T, 0);
 174	macb_or_gem_writel(bp, SA3B, 0);
 175	macb_or_gem_writel(bp, SA3T, 0);
 176	macb_or_gem_writel(bp, SA4B, 0);
 177	macb_or_gem_writel(bp, SA4T, 0);
 178}
 179
 180static void macb_get_hwaddr(struct macb *bp)
 181{
 182	struct macb_platform_data *pdata;
 183	u32 bottom;
 184	u16 top;
 185	u8 addr[6];
 186	int i;
 187
 188	pdata = dev_get_platdata(&bp->pdev->dev);
 189
 190	/* Check all 4 address register for valid address */
 191	for (i = 0; i < 4; i++) {
 192		bottom = macb_or_gem_readl(bp, SA1B + i * 8);
 193		top = macb_or_gem_readl(bp, SA1T + i * 8);
 194
 195		if (pdata && pdata->rev_eth_addr) {
 196			addr[5] = bottom & 0xff;
 197			addr[4] = (bottom >> 8) & 0xff;
 198			addr[3] = (bottom >> 16) & 0xff;
 199			addr[2] = (bottom >> 24) & 0xff;
 200			addr[1] = top & 0xff;
 201			addr[0] = (top & 0xff00) >> 8;
 202		} else {
 203			addr[0] = bottom & 0xff;
 204			addr[1] = (bottom >> 8) & 0xff;
 205			addr[2] = (bottom >> 16) & 0xff;
 206			addr[3] = (bottom >> 24) & 0xff;
 207			addr[4] = top & 0xff;
 208			addr[5] = (top >> 8) & 0xff;
 209		}
 210
 211		if (is_valid_ether_addr(addr)) {
 212			memcpy(bp->dev->dev_addr, addr, sizeof(addr));
 213			return;
 214		}
 215	}
 216
 217	dev_info(&bp->pdev->dev, "invalid hw address, using random\n");
 218	eth_hw_addr_random(bp->dev);
 219}
 220
 221static int macb_mdio_read(struct mii_bus *bus, int mii_id, int regnum)
 222{
 223	struct macb *bp = bus->priv;
 224	int value;
 225
 226	macb_writel(bp, MAN, (MACB_BF(SOF, MACB_MAN_SOF)
 227			      | MACB_BF(RW, MACB_MAN_READ)
 228			      | MACB_BF(PHYA, mii_id)
 229			      | MACB_BF(REGA, regnum)
 230			      | MACB_BF(CODE, MACB_MAN_CODE)));
 231
 232	/* wait for end of transfer */
 233	while (!MACB_BFEXT(IDLE, macb_readl(bp, NSR)))
 234		cpu_relax();
 235
 236	value = MACB_BFEXT(DATA, macb_readl(bp, MAN));
 237
 238	return value;
 239}
 240
 241static int macb_mdio_write(struct mii_bus *bus, int mii_id, int regnum,
 242			   u16 value)
 243{
 244	struct macb *bp = bus->priv;
 245
 246	macb_writel(bp, MAN, (MACB_BF(SOF, MACB_MAN_SOF)
 247			      | MACB_BF(RW, MACB_MAN_WRITE)
 248			      | MACB_BF(PHYA, mii_id)
 249			      | MACB_BF(REGA, regnum)
 250			      | MACB_BF(CODE, MACB_MAN_CODE)
 251			      | MACB_BF(DATA, value)));
 252
 253	/* wait for end of transfer */
 254	while (!MACB_BFEXT(IDLE, macb_readl(bp, NSR)))
 255		cpu_relax();
 256
 257	return 0;
 258}
 259
 260/**
 261 * macb_set_tx_clk() - Set a clock to a new frequency
 262 * @clk		Pointer to the clock to change
 263 * @rate	New frequency in Hz
 264 * @dev		Pointer to the struct net_device
 265 */
 266static void macb_set_tx_clk(struct clk *clk, int speed, struct net_device *dev)
 267{
 268	long ferr, rate, rate_rounded;
 269
 270	if (!clk)
 271		return;
 272
 273	switch (speed) {
 274	case SPEED_10:
 275		rate = 2500000;
 276		break;
 277	case SPEED_100:
 278		rate = 25000000;
 279		break;
 280	case SPEED_1000:
 281		rate = 125000000;
 282		break;
 283	default:
 284		return;
 285	}
 286
 287	rate_rounded = clk_round_rate(clk, rate);
 288	if (rate_rounded < 0)
 289		return;
 290
 291	/* RGMII allows 50 ppm frequency error. Test and warn if this limit
 292	 * is not satisfied.
 293	 */
 294	ferr = abs(rate_rounded - rate);
 295	ferr = DIV_ROUND_UP(ferr, rate / 100000);
 296	if (ferr > 5)
 297		netdev_warn(dev, "unable to generate target frequency: %ld Hz\n",
 298			    rate);
 299
 300	if (clk_set_rate(clk, rate_rounded))
 301		netdev_err(dev, "adjusting tx_clk failed.\n");
 302}
 303
 304static void macb_handle_link_change(struct net_device *dev)
 305{
 306	struct macb *bp = netdev_priv(dev);
 307	struct phy_device *phydev = dev->phydev;
 308	unsigned long flags;
 309	int status_change = 0;
 310
 311	spin_lock_irqsave(&bp->lock, flags);
 312
 313	if (phydev->link) {
 314		if ((bp->speed != phydev->speed) ||
 315		    (bp->duplex != phydev->duplex)) {
 316			u32 reg;
 317
 318			reg = macb_readl(bp, NCFGR);
 319			reg &= ~(MACB_BIT(SPD) | MACB_BIT(FD));
 320			if (macb_is_gem(bp))
 321				reg &= ~GEM_BIT(GBE);
 322
 323			if (phydev->duplex)
 324				reg |= MACB_BIT(FD);
 325			if (phydev->speed == SPEED_100)
 326				reg |= MACB_BIT(SPD);
 327			if (phydev->speed == SPEED_1000 &&
 328			    bp->caps & MACB_CAPS_GIGABIT_MODE_AVAILABLE)
 329				reg |= GEM_BIT(GBE);
 330
 331			macb_or_gem_writel(bp, NCFGR, reg);
 332
 333			bp->speed = phydev->speed;
 334			bp->duplex = phydev->duplex;
 335			status_change = 1;
 336		}
 337	}
 338
 339	if (phydev->link != bp->link) {
 340		if (!phydev->link) {
 341			bp->speed = 0;
 342			bp->duplex = -1;
 343		}
 344		bp->link = phydev->link;
 345
 346		status_change = 1;
 347	}
 348
 349	spin_unlock_irqrestore(&bp->lock, flags);
 350
 351	if (status_change) {
 352		if (phydev->link) {
 353			/* Update the TX clock rate if and only if the link is
 354			 * up and there has been a link change.
 355			 */
 356			macb_set_tx_clk(bp->tx_clk, phydev->speed, dev);
 357
 358			netif_carrier_on(dev);
 359			netdev_info(dev, "link up (%d/%s)\n",
 360				    phydev->speed,
 361				    phydev->duplex == DUPLEX_FULL ?
 362				    "Full" : "Half");
 363		} else {
 364			netif_carrier_off(dev);
 365			netdev_info(dev, "link down\n");
 366		}
 367	}
 368}
 369
 370/* based on au1000_eth. c*/
 371static int macb_mii_probe(struct net_device *dev)
 372{
 373	struct macb *bp = netdev_priv(dev);
 374	struct macb_platform_data *pdata;
 375	struct phy_device *phydev;
 376	int phy_irq;
 377	int ret;
 378
 379	phydev = phy_find_first(bp->mii_bus);
 380	if (!phydev) {
 381		netdev_err(dev, "no PHY found\n");
 382		return -ENXIO;
 383	}
 384
 385	pdata = dev_get_platdata(&bp->pdev->dev);
 386	if (pdata && gpio_is_valid(pdata->phy_irq_pin)) {
 387		ret = devm_gpio_request(&bp->pdev->dev, pdata->phy_irq_pin,
 388					"phy int");
 389		if (!ret) {
 390			phy_irq = gpio_to_irq(pdata->phy_irq_pin);
 391			phydev->irq = (phy_irq < 0) ? PHY_POLL : phy_irq;
 392		}
 393	}
 394
 395	/* attach the mac to the phy */
 396	ret = phy_connect_direct(dev, phydev, &macb_handle_link_change,
 397				 bp->phy_interface);
 398	if (ret) {
 399		netdev_err(dev, "Could not attach to PHY\n");
 400		return ret;
 401	}
 402
 403	/* mask with MAC supported features */
 404	if (macb_is_gem(bp) && bp->caps & MACB_CAPS_GIGABIT_MODE_AVAILABLE)
 405		phydev->supported &= PHY_GBIT_FEATURES;
 406	else
 407		phydev->supported &= PHY_BASIC_FEATURES;
 408
 409	if (bp->caps & MACB_CAPS_NO_GIGABIT_HALF)
 410		phydev->supported &= ~SUPPORTED_1000baseT_Half;
 411
 412	phydev->advertising = phydev->supported;
 413
 414	bp->link = 0;
 415	bp->speed = 0;
 416	bp->duplex = -1;
 417
 418	return 0;
 419}
 420
 421static int macb_mii_init(struct macb *bp)
 422{
 423	struct macb_platform_data *pdata;
 424	struct device_node *np;
 425	int err = -ENXIO, i;
 426
 427	/* Enable management port */
 428	macb_writel(bp, NCR, MACB_BIT(MPE));
 429
 430	bp->mii_bus = mdiobus_alloc();
 431	if (!bp->mii_bus) {
 432		err = -ENOMEM;
 433		goto err_out;
 434	}
 435
 436	bp->mii_bus->name = "MACB_mii_bus";
 437	bp->mii_bus->read = &macb_mdio_read;
 438	bp->mii_bus->write = &macb_mdio_write;
 439	snprintf(bp->mii_bus->id, MII_BUS_ID_SIZE, "%s-%x",
 440		 bp->pdev->name, bp->pdev->id);
 441	bp->mii_bus->priv = bp;
 442	bp->mii_bus->parent = &bp->pdev->dev;
 443	pdata = dev_get_platdata(&bp->pdev->dev);
 444
 445	dev_set_drvdata(&bp->dev->dev, bp->mii_bus);
 446
 447	np = bp->pdev->dev.of_node;
 448	if (np) {
 449		/* try dt phy registration */
 450		err = of_mdiobus_register(bp->mii_bus, np);
 451
 452		/* fallback to standard phy registration if no phy were
 453		 * found during dt phy registration
 454		 */
 455		if (!err && !phy_find_first(bp->mii_bus)) {
 456			for (i = 0; i < PHY_MAX_ADDR; i++) {
 457				struct phy_device *phydev;
 458
 459				phydev = mdiobus_scan(bp->mii_bus, i);
 460				if (IS_ERR(phydev) &&
 461				    PTR_ERR(phydev) != -ENODEV) {
 462					err = PTR_ERR(phydev);
 463					break;
 464				}
 465			}
 466
 467			if (err)
 468				goto err_out_unregister_bus;
 469		}
 470	} else {
 471		if (pdata)
 472			bp->mii_bus->phy_mask = pdata->phy_mask;
 473
 474		err = mdiobus_register(bp->mii_bus);
 475	}
 476
 477	if (err)
 478		goto err_out_free_mdiobus;
 479
 480	err = macb_mii_probe(bp->dev);
 481	if (err)
 482		goto err_out_unregister_bus;
 483
 484	return 0;
 485
 486err_out_unregister_bus:
 487	mdiobus_unregister(bp->mii_bus);
 488err_out_free_mdiobus:
 489	mdiobus_free(bp->mii_bus);
 490err_out:
 491	return err;
 492}
 493
 494static void macb_update_stats(struct macb *bp)
 495{
 496	u32 *p = &bp->hw_stats.macb.rx_pause_frames;
 497	u32 *end = &bp->hw_stats.macb.tx_pause_frames + 1;
 498	int offset = MACB_PFR;
 499
 500	WARN_ON((unsigned long)(end - p - 1) != (MACB_TPF - MACB_PFR) / 4);
 501
 502	for (; p < end; p++, offset += 4)
 503		*p += bp->macb_reg_readl(bp, offset);
 504}
 505
 506static int macb_halt_tx(struct macb *bp)
 507{
 508	unsigned long	halt_time, timeout;
 509	u32		status;
 510
 511	macb_writel(bp, NCR, macb_readl(bp, NCR) | MACB_BIT(THALT));
 512
 513	timeout = jiffies + usecs_to_jiffies(MACB_HALT_TIMEOUT);
 514	do {
 515		halt_time = jiffies;
 516		status = macb_readl(bp, TSR);
 517		if (!(status & MACB_BIT(TGO)))
 518			return 0;
 519
 520		usleep_range(10, 250);
 521	} while (time_before(halt_time, timeout));
 522
 523	return -ETIMEDOUT;
 524}
 525
 526static void macb_tx_unmap(struct macb *bp, struct macb_tx_skb *tx_skb)
 527{
 528	if (tx_skb->mapping) {
 529		if (tx_skb->mapped_as_page)
 530			dma_unmap_page(&bp->pdev->dev, tx_skb->mapping,
 531				       tx_skb->size, DMA_TO_DEVICE);
 532		else
 533			dma_unmap_single(&bp->pdev->dev, tx_skb->mapping,
 534					 tx_skb->size, DMA_TO_DEVICE);
 535		tx_skb->mapping = 0;
 536	}
 537
 538	if (tx_skb->skb) {
 539		dev_kfree_skb_any(tx_skb->skb);
 540		tx_skb->skb = NULL;
 541	}
 542}
 543
 544static void macb_tx_error_task(struct work_struct *work)
 545{
 546	struct macb_queue	*queue = container_of(work, struct macb_queue,
 547						      tx_error_task);
 548	struct macb		*bp = queue->bp;
 549	struct macb_tx_skb	*tx_skb;
 550	struct macb_dma_desc	*desc;
 551	struct sk_buff		*skb;
 552	unsigned int		tail;
 553	unsigned long		flags;
 554
 555	netdev_vdbg(bp->dev, "macb_tx_error_task: q = %u, t = %u, h = %u\n",
 556		    (unsigned int)(queue - bp->queues),
 557		    queue->tx_tail, queue->tx_head);
 558
 559	/* Prevent the queue IRQ handlers from running: each of them may call
 560	 * macb_tx_interrupt(), which in turn may call netif_wake_subqueue().
 561	 * As explained below, we have to halt the transmission before updating
 562	 * TBQP registers so we call netif_tx_stop_all_queues() to notify the
 563	 * network engine about the macb/gem being halted.
 564	 */
 565	spin_lock_irqsave(&bp->lock, flags);
 566
 567	/* Make sure nobody is trying to queue up new packets */
 568	netif_tx_stop_all_queues(bp->dev);
 569
 570	/* Stop transmission now
 571	 * (in case we have just queued new packets)
 572	 * macb/gem must be halted to write TBQP register
 573	 */
 574	if (macb_halt_tx(bp))
 575		/* Just complain for now, reinitializing TX path can be good */
 576		netdev_err(bp->dev, "BUG: halt tx timed out\n");
 577
 578	/* Treat frames in TX queue including the ones that caused the error.
 579	 * Free transmit buffers in upper layer.
 580	 */
 581	for (tail = queue->tx_tail; tail != queue->tx_head; tail++) {
 582		u32	ctrl;
 583
 584		desc = macb_tx_desc(queue, tail);
 585		ctrl = desc->ctrl;
 586		tx_skb = macb_tx_skb(queue, tail);
 587		skb = tx_skb->skb;
 588
 589		if (ctrl & MACB_BIT(TX_USED)) {
 590			/* skb is set for the last buffer of the frame */
 591			while (!skb) {
 592				macb_tx_unmap(bp, tx_skb);
 593				tail++;
 594				tx_skb = macb_tx_skb(queue, tail);
 595				skb = tx_skb->skb;
 596			}
 597
 598			/* ctrl still refers to the first buffer descriptor
 599			 * since it's the only one written back by the hardware
 600			 */
 601			if (!(ctrl & MACB_BIT(TX_BUF_EXHAUSTED))) {
 602				netdev_vdbg(bp->dev, "txerr skb %u (data %p) TX complete\n",
 603					    macb_tx_ring_wrap(tail), skb->data);
 604				bp->stats.tx_packets++;
 605				bp->stats.tx_bytes += skb->len;
 606			}
 607		} else {
 608			/* "Buffers exhausted mid-frame" errors may only happen
 609			 * if the driver is buggy, so complain loudly about
 610			 * those. Statistics are updated by hardware.
 611			 */
 612			if (ctrl & MACB_BIT(TX_BUF_EXHAUSTED))
 613				netdev_err(bp->dev,
 614					   "BUG: TX buffers exhausted mid-frame\n");
 615
 616			desc->ctrl = ctrl | MACB_BIT(TX_USED);
 617		}
 618
 619		macb_tx_unmap(bp, tx_skb);
 620	}
 621
 622	/* Set end of TX queue */
 623	desc = macb_tx_desc(queue, 0);
 624	desc->addr = 0;
 625	desc->ctrl = MACB_BIT(TX_USED);
 626
 627	/* Make descriptor updates visible to hardware */
 628	wmb();
 629
 630	/* Reinitialize the TX desc queue */
 631	queue_writel(queue, TBQP, queue->tx_ring_dma);
 632	/* Make TX ring reflect state of hardware */
 633	queue->tx_head = 0;
 634	queue->tx_tail = 0;
 635
 636	/* Housework before enabling TX IRQ */
 637	macb_writel(bp, TSR, macb_readl(bp, TSR));
 638	queue_writel(queue, IER, MACB_TX_INT_FLAGS);
 639
 640	/* Now we are ready to start transmission again */
 641	netif_tx_start_all_queues(bp->dev);
 642	macb_writel(bp, NCR, macb_readl(bp, NCR) | MACB_BIT(TSTART));
 643
 644	spin_unlock_irqrestore(&bp->lock, flags);
 645}
 646
 647static void macb_tx_interrupt(struct macb_queue *queue)
 648{
 649	unsigned int tail;
 650	unsigned int head;
 651	u32 status;
 652	struct macb *bp = queue->bp;
 653	u16 queue_index = queue - bp->queues;
 654
 655	status = macb_readl(bp, TSR);
 656	macb_writel(bp, TSR, status);
 657
 658	if (bp->caps & MACB_CAPS_ISR_CLEAR_ON_WRITE)
 659		queue_writel(queue, ISR, MACB_BIT(TCOMP));
 660
 661	netdev_vdbg(bp->dev, "macb_tx_interrupt status = 0x%03lx\n",
 662		    (unsigned long)status);
 663
 664	head = queue->tx_head;
 665	for (tail = queue->tx_tail; tail != head; tail++) {
 666		struct macb_tx_skb	*tx_skb;
 667		struct sk_buff		*skb;
 668		struct macb_dma_desc	*desc;
 669		u32			ctrl;
 670
 671		desc = macb_tx_desc(queue, tail);
 672
 673		/* Make hw descriptor updates visible to CPU */
 674		rmb();
 675
 676		ctrl = desc->ctrl;
 677
 678		/* TX_USED bit is only set by hardware on the very first buffer
 679		 * descriptor of the transmitted frame.
 680		 */
 681		if (!(ctrl & MACB_BIT(TX_USED)))
 682			break;
 683
 684		/* Process all buffers of the current transmitted frame */
 685		for (;; tail++) {
 686			tx_skb = macb_tx_skb(queue, tail);
 687			skb = tx_skb->skb;
 688
 689			/* First, update TX stats if needed */
 690			if (skb) {
 691				netdev_vdbg(bp->dev, "skb %u (data %p) TX complete\n",
 692					    macb_tx_ring_wrap(tail), skb->data);
 693				bp->stats.tx_packets++;
 694				bp->stats.tx_bytes += skb->len;
 695			}
 696
 697			/* Now we can safely release resources */
 698			macb_tx_unmap(bp, tx_skb);
 699
 700			/* skb is set only for the last buffer of the frame.
 701			 * WARNING: at this point skb has been freed by
 702			 * macb_tx_unmap().
 703			 */
 704			if (skb)
 705				break;
 706		}
 707	}
 708
 709	queue->tx_tail = tail;
 710	if (__netif_subqueue_stopped(bp->dev, queue_index) &&
 711	    CIRC_CNT(queue->tx_head, queue->tx_tail,
 712		     TX_RING_SIZE) <= MACB_TX_WAKEUP_THRESH)
 713		netif_wake_subqueue(bp->dev, queue_index);
 714}
 715
 716static void gem_rx_refill(struct macb *bp)
 717{
 718	unsigned int		entry;
 719	struct sk_buff		*skb;
 720	dma_addr_t		paddr;
 721
 722	while (CIRC_SPACE(bp->rx_prepared_head, bp->rx_tail,
 723			  RX_RING_SIZE) > 0) {
 724		entry = macb_rx_ring_wrap(bp->rx_prepared_head);
 725
 726		/* Make hw descriptor updates visible to CPU */
 727		rmb();
 728
 729		bp->rx_prepared_head++;
 730
 731		if (!bp->rx_skbuff[entry]) {
 732			/* allocate sk_buff for this free entry in ring */
 733			skb = netdev_alloc_skb(bp->dev, bp->rx_buffer_size);
 734			if (unlikely(!skb)) {
 735				netdev_err(bp->dev,
 736					   "Unable to allocate sk_buff\n");
 737				break;
 738			}
 739
 740			/* now fill corresponding descriptor entry */
 741			paddr = dma_map_single(&bp->pdev->dev, skb->data,
 742					       bp->rx_buffer_size,
 743					       DMA_FROM_DEVICE);
 744			if (dma_mapping_error(&bp->pdev->dev, paddr)) {
 745				dev_kfree_skb(skb);
 746				break;
 747			}
 748
 749			bp->rx_skbuff[entry] = skb;
 750
 751			if (entry == RX_RING_SIZE - 1)
 752				paddr |= MACB_BIT(RX_WRAP);
 753			bp->rx_ring[entry].addr = paddr;
 754			bp->rx_ring[entry].ctrl = 0;
 755
 756			/* properly align Ethernet header */
 757			skb_reserve(skb, NET_IP_ALIGN);
 758		} else {
 759			bp->rx_ring[entry].addr &= ~MACB_BIT(RX_USED);
 760			bp->rx_ring[entry].ctrl = 0;
 761		}
 762	}
 763
 764	/* Make descriptor updates visible to hardware */
 765	wmb();
 766
 767	netdev_vdbg(bp->dev, "rx ring: prepared head %d, tail %d\n",
 768		    bp->rx_prepared_head, bp->rx_tail);
 769}
 770
 771/* Mark DMA descriptors from begin up to and not including end as unused */
 772static void discard_partial_frame(struct macb *bp, unsigned int begin,
 773				  unsigned int end)
 774{
 775	unsigned int frag;
 776
 777	for (frag = begin; frag != end; frag++) {
 778		struct macb_dma_desc *desc = macb_rx_desc(bp, frag);
 779
 780		desc->addr &= ~MACB_BIT(RX_USED);
 781	}
 782
 783	/* Make descriptor updates visible to hardware */
 784	wmb();
 785
 786	/* When this happens, the hardware stats registers for
 787	 * whatever caused this is updated, so we don't have to record
 788	 * anything.
 789	 */
 790}
 791
 792static int gem_rx(struct macb *bp, int budget)
 793{
 794	unsigned int		len;
 795	unsigned int		entry;
 796	struct sk_buff		*skb;
 797	struct macb_dma_desc	*desc;
 798	int			count = 0;
 799
 800	while (count < budget) {
 801		u32 addr, ctrl;
 802
 803		entry = macb_rx_ring_wrap(bp->rx_tail);
 804		desc = &bp->rx_ring[entry];
 805
 806		/* Make hw descriptor updates visible to CPU */
 807		rmb();
 808
 809		addr = desc->addr;
 810		ctrl = desc->ctrl;
 811
 812		if (!(addr & MACB_BIT(RX_USED)))
 813			break;
 814
 815		bp->rx_tail++;
 816		count++;
 817
 818		if (!(ctrl & MACB_BIT(RX_SOF) && ctrl & MACB_BIT(RX_EOF))) {
 819			netdev_err(bp->dev,
 820				   "not whole frame pointed by descriptor\n");
 821			bp->stats.rx_dropped++;
 822			break;
 823		}
 824		skb = bp->rx_skbuff[entry];
 825		if (unlikely(!skb)) {
 826			netdev_err(bp->dev,
 827				   "inconsistent Rx descriptor chain\n");
 828			bp->stats.rx_dropped++;
 829			break;
 830		}
 831		/* now everything is ready for receiving packet */
 832		bp->rx_skbuff[entry] = NULL;
 833		len = ctrl & bp->rx_frm_len_mask;
 834
 835		netdev_vdbg(bp->dev, "gem_rx %u (len %u)\n", entry, len);
 836
 837		skb_put(skb, len);
 838		addr = MACB_BF(RX_WADDR, MACB_BFEXT(RX_WADDR, addr));
 839		dma_unmap_single(&bp->pdev->dev, addr,
 840				 bp->rx_buffer_size, DMA_FROM_DEVICE);
 841
 842		skb->protocol = eth_type_trans(skb, bp->dev);
 843		skb_checksum_none_assert(skb);
 844		if (bp->dev->features & NETIF_F_RXCSUM &&
 845		    !(bp->dev->flags & IFF_PROMISC) &&
 846		    GEM_BFEXT(RX_CSUM, ctrl) & GEM_RX_CSUM_CHECKED_MASK)
 847			skb->ip_summed = CHECKSUM_UNNECESSARY;
 848
 849		bp->stats.rx_packets++;
 850		bp->stats.rx_bytes += skb->len;
 851
 852#if defined(DEBUG) && defined(VERBOSE_DEBUG)
 853		netdev_vdbg(bp->dev, "received skb of length %u, csum: %08x\n",
 854			    skb->len, skb->csum);
 855		print_hex_dump(KERN_DEBUG, " mac: ", DUMP_PREFIX_ADDRESS, 16, 1,
 856			       skb_mac_header(skb), 16, true);
 857		print_hex_dump(KERN_DEBUG, "data: ", DUMP_PREFIX_ADDRESS, 16, 1,
 858			       skb->data, 32, true);
 859#endif
 860
 861		netif_receive_skb(skb);
 862	}
 863
 864	gem_rx_refill(bp);
 865
 866	return count;
 867}
 868
 869static int macb_rx_frame(struct macb *bp, unsigned int first_frag,
 870			 unsigned int last_frag)
 871{
 872	unsigned int len;
 873	unsigned int frag;
 874	unsigned int offset;
 875	struct sk_buff *skb;
 876	struct macb_dma_desc *desc;
 877
 878	desc = macb_rx_desc(bp, last_frag);
 879	len = desc->ctrl & bp->rx_frm_len_mask;
 880
 881	netdev_vdbg(bp->dev, "macb_rx_frame frags %u - %u (len %u)\n",
 882		    macb_rx_ring_wrap(first_frag),
 883		    macb_rx_ring_wrap(last_frag), len);
 884
 885	/* The ethernet header starts NET_IP_ALIGN bytes into the
 886	 * first buffer. Since the header is 14 bytes, this makes the
 887	 * payload word-aligned.
 888	 *
 889	 * Instead of calling skb_reserve(NET_IP_ALIGN), we just copy
 890	 * the two padding bytes into the skb so that we avoid hitting
 891	 * the slowpath in memcpy(), and pull them off afterwards.
 892	 */
 893	skb = netdev_alloc_skb(bp->dev, len + NET_IP_ALIGN);
 894	if (!skb) {
 895		bp->stats.rx_dropped++;
 896		for (frag = first_frag; ; frag++) {
 897			desc = macb_rx_desc(bp, frag);
 898			desc->addr &= ~MACB_BIT(RX_USED);
 899			if (frag == last_frag)
 900				break;
 901		}
 902
 903		/* Make descriptor updates visible to hardware */
 904		wmb();
 905
 906		return 1;
 907	}
 908
 909	offset = 0;
 910	len += NET_IP_ALIGN;
 911	skb_checksum_none_assert(skb);
 912	skb_put(skb, len);
 913
 914	for (frag = first_frag; ; frag++) {
 915		unsigned int frag_len = bp->rx_buffer_size;
 916
 917		if (offset + frag_len > len) {
 918			if (unlikely(frag != last_frag)) {
 919				dev_kfree_skb_any(skb);
 920				return -1;
 921			}
 922			frag_len = len - offset;
 923		}
 924		skb_copy_to_linear_data_offset(skb, offset,
 925					       macb_rx_buffer(bp, frag),
 926					       frag_len);
 927		offset += bp->rx_buffer_size;
 928		desc = macb_rx_desc(bp, frag);
 929		desc->addr &= ~MACB_BIT(RX_USED);
 930
 931		if (frag == last_frag)
 932			break;
 933	}
 934
 935	/* Make descriptor updates visible to hardware */
 936	wmb();
 937
 938	__skb_pull(skb, NET_IP_ALIGN);
 939	skb->protocol = eth_type_trans(skb, bp->dev);
 940
 941	bp->stats.rx_packets++;
 942	bp->stats.rx_bytes += skb->len;
 943	netdev_vdbg(bp->dev, "received skb of length %u, csum: %08x\n",
 944		    skb->len, skb->csum);
 945	netif_receive_skb(skb);
 946
 947	return 0;
 948}
 949
 950static inline void macb_init_rx_ring(struct macb *bp)
 951{
 952	dma_addr_t addr;
 953	int i;
 954
 955	addr = bp->rx_buffers_dma;
 956	for (i = 0; i < RX_RING_SIZE; i++) {
 957		bp->rx_ring[i].addr = addr;
 958		bp->rx_ring[i].ctrl = 0;
 959		addr += bp->rx_buffer_size;
 960	}
 961	bp->rx_ring[RX_RING_SIZE - 1].addr |= MACB_BIT(RX_WRAP);
 962}
 963
 964static int macb_rx(struct macb *bp, int budget)
 965{
 966	bool reset_rx_queue = false;
 967	int received = 0;
 968	unsigned int tail;
 969	int first_frag = -1;
 970
 971	for (tail = bp->rx_tail; budget > 0; tail++) {
 972		struct macb_dma_desc *desc = macb_rx_desc(bp, tail);
 973		u32 addr, ctrl;
 974
 975		/* Make hw descriptor updates visible to CPU */
 976		rmb();
 977
 978		addr = desc->addr;
 979		ctrl = desc->ctrl;
 980
 981		if (!(addr & MACB_BIT(RX_USED)))
 982			break;
 983
 984		if (ctrl & MACB_BIT(RX_SOF)) {
 985			if (first_frag != -1)
 986				discard_partial_frame(bp, first_frag, tail);
 987			first_frag = tail;
 988		}
 989
 990		if (ctrl & MACB_BIT(RX_EOF)) {
 991			int dropped;
 992
 993			if (unlikely(first_frag == -1)) {
 994				reset_rx_queue = true;
 995				continue;
 996			}
 997
 998			dropped = macb_rx_frame(bp, first_frag, tail);
 999			first_frag = -1;
1000			if (unlikely(dropped < 0)) {
1001				reset_rx_queue = true;
1002				continue;
1003			}
1004			if (!dropped) {
1005				received++;
1006				budget--;
1007			}
1008		}
1009	}
1010
1011	if (unlikely(reset_rx_queue)) {
1012		unsigned long flags;
1013		u32 ctrl;
1014
1015		netdev_err(bp->dev, "RX queue corruption: reset it\n");
1016
1017		spin_lock_irqsave(&bp->lock, flags);
1018
1019		ctrl = macb_readl(bp, NCR);
1020		macb_writel(bp, NCR, ctrl & ~MACB_BIT(RE));
1021
1022		macb_init_rx_ring(bp);
1023		macb_writel(bp, RBQP, bp->rx_ring_dma);
1024
1025		macb_writel(bp, NCR, ctrl | MACB_BIT(RE));
1026
1027		spin_unlock_irqrestore(&bp->lock, flags);
1028		return received;
1029	}
1030
1031	if (first_frag != -1)
1032		bp->rx_tail = first_frag;
1033	else
1034		bp->rx_tail = tail;
1035
1036	return received;
1037}
1038
1039static int macb_poll(struct napi_struct *napi, int budget)
1040{
1041	struct macb *bp = container_of(napi, struct macb, napi);
1042	int work_done;
1043	u32 status;
1044
1045	status = macb_readl(bp, RSR);
1046	macb_writel(bp, RSR, status);
1047
1048	work_done = 0;
1049
1050	netdev_vdbg(bp->dev, "poll: status = %08lx, budget = %d\n",
1051		    (unsigned long)status, budget);
1052
1053	work_done = bp->macbgem_ops.mog_rx(bp, budget);
1054	if (work_done < budget) {
1055		napi_complete(napi);
1056
1057		/* Packets received while interrupts were disabled */
1058		status = macb_readl(bp, RSR);
1059		if (status) {
1060			if (bp->caps & MACB_CAPS_ISR_CLEAR_ON_WRITE)
1061				macb_writel(bp, ISR, MACB_BIT(RCOMP));
1062			napi_reschedule(napi);
1063		} else {
1064			macb_writel(bp, IER, MACB_RX_INT_FLAGS);
1065		}
1066	}
1067
1068	/* TODO: Handle errors */
1069
1070	return work_done;
1071}
1072
1073static irqreturn_t macb_interrupt(int irq, void *dev_id)
1074{
1075	struct macb_queue *queue = dev_id;
1076	struct macb *bp = queue->bp;
1077	struct net_device *dev = bp->dev;
1078	u32 status, ctrl;
1079
1080	status = queue_readl(queue, ISR);
1081
1082	if (unlikely(!status))
1083		return IRQ_NONE;
1084
1085	spin_lock(&bp->lock);
1086
1087	while (status) {
1088		/* close possible race with dev_close */
1089		if (unlikely(!netif_running(dev))) {
1090			queue_writel(queue, IDR, -1);
1091			if (bp->caps & MACB_CAPS_ISR_CLEAR_ON_WRITE)
1092				queue_writel(queue, ISR, -1);
1093			break;
1094		}
1095
1096		netdev_vdbg(bp->dev, "queue = %u, isr = 0x%08lx\n",
1097			    (unsigned int)(queue - bp->queues),
1098			    (unsigned long)status);
1099
1100		if (status & MACB_RX_INT_FLAGS) {
1101			/* There's no point taking any more interrupts
1102			 * until we have processed the buffers. The
1103			 * scheduling call may fail if the poll routine
1104			 * is already scheduled, so disable interrupts
1105			 * now.
1106			 */
1107			queue_writel(queue, IDR, MACB_RX_INT_FLAGS);
1108			if (bp->caps & MACB_CAPS_ISR_CLEAR_ON_WRITE)
1109				queue_writel(queue, ISR, MACB_BIT(RCOMP));
1110
1111			if (napi_schedule_prep(&bp->napi)) {
1112				netdev_vdbg(bp->dev, "scheduling RX softirq\n");
1113				__napi_schedule(&bp->napi);
1114			}
1115		}
1116
1117		if (unlikely(status & (MACB_TX_ERR_FLAGS))) {
1118			queue_writel(queue, IDR, MACB_TX_INT_FLAGS);
1119			schedule_work(&queue->tx_error_task);
1120
1121			if (bp->caps & MACB_CAPS_ISR_CLEAR_ON_WRITE)
1122				queue_writel(queue, ISR, MACB_TX_ERR_FLAGS);
1123
1124			break;
1125		}
1126
1127		if (status & MACB_BIT(TCOMP))
1128			macb_tx_interrupt(queue);
1129
1130		/* Link change detection isn't possible with RMII, so we'll
1131		 * add that if/when we get our hands on a full-blown MII PHY.
1132		 */
1133
1134		/* There is a hardware issue under heavy load where DMA can
1135		 * stop, this causes endless "used buffer descriptor read"
1136		 * interrupts but it can be cleared by re-enabling RX. See
1137		 * the at91 manual, section 41.3.1 or the Zynq manual
1138		 * section 16.7.4 for details.
1139		 */
1140		if (status & MACB_BIT(RXUBR)) {
1141			ctrl = macb_readl(bp, NCR);
1142			macb_writel(bp, NCR, ctrl & ~MACB_BIT(RE));
1143			macb_writel(bp, NCR, ctrl | MACB_BIT(RE));
1144
1145			if (bp->caps & MACB_CAPS_ISR_CLEAR_ON_WRITE)
1146				queue_writel(queue, ISR, MACB_BIT(RXUBR));
1147		}
1148
1149		if (status & MACB_BIT(ISR_ROVR)) {
1150			/* We missed at least one packet */
1151			if (macb_is_gem(bp))
1152				bp->hw_stats.gem.rx_overruns++;
1153			else
1154				bp->hw_stats.macb.rx_overruns++;
1155
1156			if (bp->caps & MACB_CAPS_ISR_CLEAR_ON_WRITE)
1157				queue_writel(queue, ISR, MACB_BIT(ISR_ROVR));
1158		}
1159
1160		if (status & MACB_BIT(HRESP)) {
1161			/* TODO: Reset the hardware, and maybe move the
1162			 * netdev_err to a lower-priority context as well
1163			 * (work queue?)
1164			 */
1165			netdev_err(dev, "DMA bus error: HRESP not OK\n");
1166
1167			if (bp->caps & MACB_CAPS_ISR_CLEAR_ON_WRITE)
1168				queue_writel(queue, ISR, MACB_BIT(HRESP));
1169		}
1170
1171		status = queue_readl(queue, ISR);
1172	}
1173
1174	spin_unlock(&bp->lock);
1175
1176	return IRQ_HANDLED;
1177}
1178
1179#ifdef CONFIG_NET_POLL_CONTROLLER
1180/* Polling receive - used by netconsole and other diagnostic tools
1181 * to allow network i/o with interrupts disabled.
1182 */
1183static void macb_poll_controller(struct net_device *dev)
1184{
1185	struct macb *bp = netdev_priv(dev);
1186	struct macb_queue *queue;
1187	unsigned long flags;
1188	unsigned int q;
1189
1190	local_irq_save(flags);
1191	for (q = 0, queue = bp->queues; q < bp->num_queues; ++q, ++queue)
1192		macb_interrupt(dev->irq, queue);
1193	local_irq_restore(flags);
1194}
1195#endif
1196
1197static unsigned int macb_tx_map(struct macb *bp,
1198				struct macb_queue *queue,
1199				struct sk_buff *skb)
1200{
1201	dma_addr_t mapping;
1202	unsigned int len, entry, i, tx_head = queue->tx_head;
1203	struct macb_tx_skb *tx_skb = NULL;
1204	struct macb_dma_desc *desc;
1205	unsigned int offset, size, count = 0;
1206	unsigned int f, nr_frags = skb_shinfo(skb)->nr_frags;
1207	unsigned int eof = 1;
1208	u32 ctrl;
1209
1210	/* First, map non-paged data */
1211	len = skb_headlen(skb);
1212	offset = 0;
1213	while (len) {
1214		size = min(len, bp->max_tx_length);
1215		entry = macb_tx_ring_wrap(tx_head);
1216		tx_skb = &queue->tx_skb[entry];
1217
1218		mapping = dma_map_single(&bp->pdev->dev,
1219					 skb->data + offset,
1220					 size, DMA_TO_DEVICE);
1221		if (dma_mapping_error(&bp->pdev->dev, mapping))
1222			goto dma_error;
1223
1224		/* Save info to properly release resources */
1225		tx_skb->skb = NULL;
1226		tx_skb->mapping = mapping;
1227		tx_skb->size = size;
1228		tx_skb->mapped_as_page = false;
1229
1230		len -= size;
1231		offset += size;
1232		count++;
1233		tx_head++;
1234	}
1235
1236	/* Then, map paged data from fragments */
1237	for (f = 0; f < nr_frags; f++) {
1238		const skb_frag_t *frag = &skb_shinfo(skb)->frags[f];
1239
1240		len = skb_frag_size(frag);
1241		offset = 0;
1242		while (len) {
1243			size = min(len, bp->max_tx_length);
1244			entry = macb_tx_ring_wrap(tx_head);
1245			tx_skb = &queue->tx_skb[entry];
1246
1247			mapping = skb_frag_dma_map(&bp->pdev->dev, frag,
1248						   offset, size, DMA_TO_DEVICE);
1249			if (dma_mapping_error(&bp->pdev->dev, mapping))
1250				goto dma_error;
1251
1252			/* Save info to properly release resources */
1253			tx_skb->skb = NULL;
1254			tx_skb->mapping = mapping;
1255			tx_skb->size = size;
1256			tx_skb->mapped_as_page = true;
1257
1258			len -= size;
1259			offset += size;
1260			count++;
1261			tx_head++;
1262		}
1263	}
1264
1265	/* Should never happen */
1266	if (unlikely(!tx_skb)) {
1267		netdev_err(bp->dev, "BUG! empty skb!\n");
1268		return 0;
1269	}
1270
1271	/* This is the last buffer of the frame: save socket buffer */
1272	tx_skb->skb = skb;
1273
1274	/* Update TX ring: update buffer descriptors in reverse order
1275	 * to avoid race condition
1276	 */
1277
1278	/* Set 'TX_USED' bit in buffer descriptor at tx_head position
1279	 * to set the end of TX queue
1280	 */
1281	i = tx_head;
1282	entry = macb_tx_ring_wrap(i);
1283	ctrl = MACB_BIT(TX_USED);
1284	desc = &queue->tx_ring[entry];
1285	desc->ctrl = ctrl;
1286
1287	do {
1288		i--;
1289		entry = macb_tx_ring_wrap(i);
1290		tx_skb = &queue->tx_skb[entry];
1291		desc = &queue->tx_ring[entry];
1292
1293		ctrl = (u32)tx_skb->size;
1294		if (eof) {
1295			ctrl |= MACB_BIT(TX_LAST);
1296			eof = 0;
1297		}
1298		if (unlikely(entry == (TX_RING_SIZE - 1)))
1299			ctrl |= MACB_BIT(TX_WRAP);
1300
1301		/* Set TX buffer descriptor */
1302		desc->addr = tx_skb->mapping;
1303		/* desc->addr must be visible to hardware before clearing
1304		 * 'TX_USED' bit in desc->ctrl.
1305		 */
1306		wmb();
1307		desc->ctrl = ctrl;
1308	} while (i != queue->tx_head);
1309
1310	queue->tx_head = tx_head;
1311
1312	return count;
1313
1314dma_error:
1315	netdev_err(bp->dev, "TX DMA map failed\n");
1316
1317	for (i = queue->tx_head; i != tx_head; i++) {
1318		tx_skb = macb_tx_skb(queue, i);
1319
1320		macb_tx_unmap(bp, tx_skb);
1321	}
1322
1323	return 0;
1324}
1325
1326static int macb_start_xmit(struct sk_buff *skb, struct net_device *dev)
1327{
1328	u16 queue_index = skb_get_queue_mapping(skb);
1329	struct macb *bp = netdev_priv(dev);
1330	struct macb_queue *queue = &bp->queues[queue_index];
1331	unsigned long flags;
1332	unsigned int count, nr_frags, frag_size, f;
1333
1334#if defined(DEBUG) && defined(VERBOSE_DEBUG)
1335	netdev_vdbg(bp->dev,
1336		    "start_xmit: queue %hu len %u head %p data %p tail %p end %p\n",
1337		    queue_index, skb->len, skb->head, skb->data,
1338		    skb_tail_pointer(skb), skb_end_pointer(skb));
1339	print_hex_dump(KERN_DEBUG, "data: ", DUMP_PREFIX_OFFSET, 16, 1,
1340		       skb->data, 16, true);
1341#endif
1342
1343	/* Count how many TX buffer descriptors are needed to send this
1344	 * socket buffer: skb fragments of jumbo frames may need to be
1345	 * split into many buffer descriptors.
1346	 */
1347	count = DIV_ROUND_UP(skb_headlen(skb), bp->max_tx_length);
1348	nr_frags = skb_shinfo(skb)->nr_frags;
1349	for (f = 0; f < nr_frags; f++) {
1350		frag_size = skb_frag_size(&skb_shinfo(skb)->frags[f]);
1351		count += DIV_ROUND_UP(frag_size, bp->max_tx_length);
1352	}
1353
1354	spin_lock_irqsave(&bp->lock, flags);
1355
1356	/* This is a hard error, log it. */
1357	if (CIRC_SPACE(queue->tx_head, queue->tx_tail, TX_RING_SIZE) < count) {
1358		netif_stop_subqueue(dev, queue_index);
1359		spin_unlock_irqrestore(&bp->lock, flags);
1360		netdev_dbg(bp->dev, "tx_head = %u, tx_tail = %u\n",
1361			   queue->tx_head, queue->tx_tail);
1362		return NETDEV_TX_BUSY;
1363	}
1364
1365	/* Map socket buffer for DMA transfer */
1366	if (!macb_tx_map(bp, queue, skb)) {
1367		dev_kfree_skb_any(skb);
1368		goto unlock;
1369	}
1370
1371	/* Make newly initialized descriptor visible to hardware */
1372	wmb();
1373
1374	skb_tx_timestamp(skb);
1375
1376	macb_writel(bp, NCR, macb_readl(bp, NCR) | MACB_BIT(TSTART));
1377
1378	if (CIRC_SPACE(queue->tx_head, queue->tx_tail, TX_RING_SIZE) < 1)
1379		netif_stop_subqueue(dev, queue_index);
1380
1381unlock:
1382	spin_unlock_irqrestore(&bp->lock, flags);
1383
1384	return NETDEV_TX_OK;
1385}
1386
1387static void macb_init_rx_buffer_size(struct macb *bp, size_t size)
1388{
1389	if (!macb_is_gem(bp)) {
1390		bp->rx_buffer_size = MACB_RX_BUFFER_SIZE;
1391	} else {
1392		bp->rx_buffer_size = size;
1393
1394		if (bp->rx_buffer_size % RX_BUFFER_MULTIPLE) {
1395			netdev_dbg(bp->dev,
1396				   "RX buffer must be multiple of %d bytes, expanding\n",
1397				   RX_BUFFER_MULTIPLE);
1398			bp->rx_buffer_size =
1399				roundup(bp->rx_buffer_size, RX_BUFFER_MULTIPLE);
1400		}
1401	}
1402
1403	netdev_dbg(bp->dev, "mtu [%u] rx_buffer_size [%Zu]\n",
1404		   bp->dev->mtu, bp->rx_buffer_size);
1405}
1406
1407static void gem_free_rx_buffers(struct macb *bp)
1408{
1409	struct sk_buff		*skb;
1410	struct macb_dma_desc	*desc;
1411	dma_addr_t		addr;
1412	int i;
1413
1414	if (!bp->rx_skbuff)
1415		return;
1416
1417	for (i = 0; i < RX_RING_SIZE; i++) {
1418		skb = bp->rx_skbuff[i];
1419
1420		if (!skb)
1421			continue;
1422
1423		desc = &bp->rx_ring[i];
1424		addr = MACB_BF(RX_WADDR, MACB_BFEXT(RX_WADDR, desc->addr));
1425		dma_unmap_single(&bp->pdev->dev, addr, bp->rx_buffer_size,
1426				 DMA_FROM_DEVICE);
1427		dev_kfree_skb_any(skb);
1428		skb = NULL;
1429	}
1430
1431	kfree(bp->rx_skbuff);
1432	bp->rx_skbuff = NULL;
1433}
1434
1435static void macb_free_rx_buffers(struct macb *bp)
1436{
1437	if (bp->rx_buffers) {
1438		dma_free_coherent(&bp->pdev->dev,
1439				  RX_RING_SIZE * bp->rx_buffer_size,
1440				  bp->rx_buffers, bp->rx_buffers_dma);
1441		bp->rx_buffers = NULL;
1442	}
1443}
1444
1445static void macb_free_consistent(struct macb *bp)
1446{
1447	struct macb_queue *queue;
1448	unsigned int q;
1449
1450	bp->macbgem_ops.mog_free_rx_buffers(bp);
1451	if (bp->rx_ring) {
1452		dma_free_coherent(&bp->pdev->dev, RX_RING_BYTES,
1453				  bp->rx_ring, bp->rx_ring_dma);
1454		bp->rx_ring = NULL;
1455	}
1456
1457	for (q = 0, queue = bp->queues; q < bp->num_queues; ++q, ++queue) {
1458		kfree(queue->tx_skb);
1459		queue->tx_skb = NULL;
1460		if (queue->tx_ring) {
1461			dma_free_coherent(&bp->pdev->dev, TX_RING_BYTES,
1462					  queue->tx_ring, queue->tx_ring_dma);
1463			queue->tx_ring = NULL;
1464		}
1465	}
1466}
1467
1468static int gem_alloc_rx_buffers(struct macb *bp)
1469{
1470	int size;
1471
1472	size = RX_RING_SIZE * sizeof(struct sk_buff *);
1473	bp->rx_skbuff = kzalloc(size, GFP_KERNEL);
1474	if (!bp->rx_skbuff)
1475		return -ENOMEM;
1476
1477	netdev_dbg(bp->dev,
1478		   "Allocated %d RX struct sk_buff entries at %p\n",
1479		   RX_RING_SIZE, bp->rx_skbuff);
1480	return 0;
1481}
1482
1483static int macb_alloc_rx_buffers(struct macb *bp)
1484{
1485	int size;
1486
1487	size = RX_RING_SIZE * bp->rx_buffer_size;
1488	bp->rx_buffers = dma_alloc_coherent(&bp->pdev->dev, size,
1489					    &bp->rx_buffers_dma, GFP_KERNEL);
1490	if (!bp->rx_buffers)
1491		return -ENOMEM;
1492
1493	netdev_dbg(bp->dev,
1494		   "Allocated RX buffers of %d bytes at %08lx (mapped %p)\n",
1495		   size, (unsigned long)bp->rx_buffers_dma, bp->rx_buffers);
1496	return 0;
1497}
1498
1499static int macb_alloc_consistent(struct macb *bp)
1500{
1501	struct macb_queue *queue;
1502	unsigned int q;
1503	int size;
1504
1505	for (q = 0, queue = bp->queues; q < bp->num_queues; ++q, ++queue) {
1506		size = TX_RING_BYTES;
1507		queue->tx_ring = dma_alloc_coherent(&bp->pdev->dev, size,
1508						    &queue->tx_ring_dma,
1509						    GFP_KERNEL);
1510		if (!queue->tx_ring)
1511			goto out_err;
1512		netdev_dbg(bp->dev,
1513			   "Allocated TX ring for queue %u of %d bytes at %08lx (mapped %p)\n",
1514			   q, size, (unsigned long)queue->tx_ring_dma,
1515			   queue->tx_ring);
1516
1517		size = TX_RING_SIZE * sizeof(struct macb_tx_skb);
1518		queue->tx_skb = kmalloc(size, GFP_KERNEL);
1519		if (!queue->tx_skb)
1520			goto out_err;
1521	}
1522
1523	size = RX_RING_BYTES;
1524	bp->rx_ring = dma_alloc_coherent(&bp->pdev->dev, size,
1525					 &bp->rx_ring_dma, GFP_KERNEL);
1526	if (!bp->rx_ring)
1527		goto out_err;
1528	netdev_dbg(bp->dev,
1529		   "Allocated RX ring of %d bytes at %08lx (mapped %p)\n",
1530		   size, (unsigned long)bp->rx_ring_dma, bp->rx_ring);
1531
1532	if (bp->macbgem_ops.mog_alloc_rx_buffers(bp))
1533		goto out_err;
1534
1535	return 0;
1536
1537out_err:
1538	macb_free_consistent(bp);
1539	return -ENOMEM;
1540}
1541
1542static void gem_init_rings(struct macb *bp)
1543{
1544	struct macb_queue *queue;
1545	unsigned int q;
1546	int i;
1547
1548	for (q = 0, queue = bp->queues; q < bp->num_queues; ++q, ++queue) {
1549		for (i = 0; i < TX_RING_SIZE; i++) {
1550			queue->tx_ring[i].addr = 0;
1551			queue->tx_ring[i].ctrl = MACB_BIT(TX_USED);
1552		}
1553		queue->tx_ring[TX_RING_SIZE - 1].ctrl |= MACB_BIT(TX_WRAP);
1554		queue->tx_head = 0;
1555		queue->tx_tail = 0;
1556	}
1557
1558	bp->rx_tail = 0;
1559	bp->rx_prepared_head = 0;
1560
1561	gem_rx_refill(bp);
1562}
1563
1564static void macb_init_rings(struct macb *bp)
1565{
1566	int i;
1567
1568	macb_init_rx_ring(bp);
1569
1570	for (i = 0; i < TX_RING_SIZE; i++) {
1571		bp->queues[0].tx_ring[i].addr = 0;
1572		bp->queues[0].tx_ring[i].ctrl = MACB_BIT(TX_USED);
1573	}
1574	bp->queues[0].tx_head = 0;
1575	bp->queues[0].tx_tail = 0;
1576	bp->queues[0].tx_ring[TX_RING_SIZE - 1].ctrl |= MACB_BIT(TX_WRAP);
1577
1578	bp->rx_tail = 0;
1579}
1580
1581static void macb_reset_hw(struct macb *bp)
1582{
1583	struct macb_queue *queue;
1584	unsigned int q;
1585
1586	/* Disable RX and TX (XXX: Should we halt the transmission
1587	 * more gracefully?)
1588	 */
1589	macb_writel(bp, NCR, 0);
1590
1591	/* Clear the stats registers (XXX: Update stats first?) */
1592	macb_writel(bp, NCR, MACB_BIT(CLRSTAT));
1593
1594	/* Clear all status flags */
1595	macb_writel(bp, TSR, -1);
1596	macb_writel(bp, RSR, -1);
1597
1598	/* Disable all interrupts */
1599	for (q = 0, queue = bp->queues; q < bp->num_queues; ++q, ++queue) {
1600		queue_writel(queue, IDR, -1);
1601		queue_readl(queue, ISR);
1602		if (bp->caps & MACB_CAPS_ISR_CLEAR_ON_WRITE)
1603			queue_writel(queue, ISR, -1);
1604	}
1605}
1606
1607static u32 gem_mdc_clk_div(struct macb *bp)
1608{
1609	u32 config;
1610	unsigned long pclk_hz = clk_get_rate(bp->pclk);
1611
1612	if (pclk_hz <= 20000000)
1613		config = GEM_BF(CLK, GEM_CLK_DIV8);
1614	else if (pclk_hz <= 40000000)
1615		config = GEM_BF(CLK, GEM_CLK_DIV16);
1616	else if (pclk_hz <= 80000000)
1617		config = GEM_BF(CLK, GEM_CLK_DIV32);
1618	else if (pclk_hz <= 120000000)
1619		config = GEM_BF(CLK, GEM_CLK_DIV48);
1620	else if (pclk_hz <= 160000000)
1621		config = GEM_BF(CLK, GEM_CLK_DIV64);
1622	else
1623		config = GEM_BF(CLK, GEM_CLK_DIV96);
1624
1625	return config;
1626}
1627
1628static u32 macb_mdc_clk_div(struct macb *bp)
1629{
1630	u32 config;
1631	unsigned long pclk_hz;
1632
1633	if (macb_is_gem(bp))
1634		return gem_mdc_clk_div(bp);
1635
1636	pclk_hz = clk_get_rate(bp->pclk);
1637	if (pclk_hz <= 20000000)
1638		config = MACB_BF(CLK, MACB_CLK_DIV8);
1639	else if (pclk_hz <= 40000000)
1640		config = MACB_BF(CLK, MACB_CLK_DIV16);
1641	else if (pclk_hz <= 80000000)
1642		config = MACB_BF(CLK, MACB_CLK_DIV32);
1643	else
1644		config = MACB_BF(CLK, MACB_CLK_DIV64);
1645
1646	return config;
1647}
1648
1649/* Get the DMA bus width field of the network configuration register that we
1650 * should program.  We find the width from decoding the design configuration
1651 * register to find the maximum supported data bus width.
1652 */
1653static u32 macb_dbw(struct macb *bp)
1654{
1655	if (!macb_is_gem(bp))
1656		return 0;
1657
1658	switch (GEM_BFEXT(DBWDEF, gem_readl(bp, DCFG1))) {
1659	case 4:
1660		return GEM_BF(DBW, GEM_DBW128);
1661	case 2:
1662		return GEM_BF(DBW, GEM_DBW64);
1663	case 1:
1664	default:
1665		return GEM_BF(DBW, GEM_DBW32);
1666	}
1667}
1668
1669/* Configure the receive DMA engine
1670 * - use the correct receive buffer size
1671 * - set best burst length for DMA operations
1672 *   (if not supported by FIFO, it will fallback to default)
1673 * - set both rx/tx packet buffers to full memory size
1674 * These are configurable parameters for GEM.
1675 */
1676static void macb_configure_dma(struct macb *bp)
1677{
1678	u32 dmacfg;
1679
1680	if (macb_is_gem(bp)) {
1681		dmacfg = gem_readl(bp, DMACFG) & ~GEM_BF(RXBS, -1L);
1682		dmacfg |= GEM_BF(RXBS, bp->rx_buffer_size / RX_BUFFER_MULTIPLE);
1683		if (bp->dma_burst_length)
1684			dmacfg = GEM_BFINS(FBLDO, bp->dma_burst_length, dmacfg);
1685		dmacfg |= GEM_BIT(TXPBMS) | GEM_BF(RXBMS, -1L);
1686		dmacfg &= ~GEM_BIT(ENDIA_PKT);
1687
1688		if (bp->native_io)
1689			dmacfg &= ~GEM_BIT(ENDIA_DESC);
1690		else
1691			dmacfg |= GEM_BIT(ENDIA_DESC); /* CPU in big endian */
1692
1693		if (bp->dev->features & NETIF_F_HW_CSUM)
1694			dmacfg |= GEM_BIT(TXCOEN);
1695		else
1696			dmacfg &= ~GEM_BIT(TXCOEN);
1697		netdev_dbg(bp->dev, "Cadence configure DMA with 0x%08x\n",
1698			   dmacfg);
1699		gem_writel(bp, DMACFG, dmacfg);
1700	}
1701}
1702
1703static void macb_init_hw(struct macb *bp)
1704{
1705	struct macb_queue *queue;
1706	unsigned int q;
1707
1708	u32 config;
1709
1710	macb_reset_hw(bp);
1711	macb_set_hwaddr(bp);
1712
1713	config = macb_mdc_clk_div(bp);
1714	if (bp->phy_interface == PHY_INTERFACE_MODE_SGMII)
1715		config |= GEM_BIT(SGMIIEN) | GEM_BIT(PCSSEL);
1716	config |= MACB_BF(RBOF, NET_IP_ALIGN);	/* Make eth data aligned */
1717	config |= MACB_BIT(PAE);		/* PAuse Enable */
1718	config |= MACB_BIT(DRFCS);		/* Discard Rx FCS */
1719	if (bp->caps & MACB_CAPS_JUMBO)
1720		config |= MACB_BIT(JFRAME);	/* Enable jumbo frames */
1721	else
1722		config |= MACB_BIT(BIG);	/* Receive oversized frames */
1723	if (bp->dev->flags & IFF_PROMISC)
1724		config |= MACB_BIT(CAF);	/* Copy All Frames */
1725	else if (macb_is_gem(bp) && bp->dev->features & NETIF_F_RXCSUM)
1726		config |= GEM_BIT(RXCOEN);
1727	if (!(bp->dev->flags & IFF_BROADCAST))
1728		config |= MACB_BIT(NBC);	/* No BroadCast */
1729	config |= macb_dbw(bp);
1730	macb_writel(bp, NCFGR, config);
1731	if ((bp->caps & MACB_CAPS_JUMBO) && bp->jumbo_max_len)
1732		gem_writel(bp, JML, bp->jumbo_max_len);
1733	bp->speed = SPEED_10;
1734	bp->duplex = DUPLEX_HALF;
1735	bp->rx_frm_len_mask = MACB_RX_FRMLEN_MASK;
1736	if (bp->caps & MACB_CAPS_JUMBO)
1737		bp->rx_frm_len_mask = MACB_RX_JFRMLEN_MASK;
1738
1739	macb_configure_dma(bp);
1740
1741	/* Initialize TX and RX buffers */
1742	macb_writel(bp, RBQP, bp->rx_ring_dma);
1743	for (q = 0, queue = bp->queues; q < bp->num_queues; ++q, ++queue) {
1744		queue_writel(queue, TBQP, queue->tx_ring_dma);
1745
1746		/* Enable interrupts */
1747		queue_writel(queue, IER,
1748			     MACB_RX_INT_FLAGS |
1749			     MACB_TX_INT_FLAGS |
1750			     MACB_BIT(HRESP));
1751	}
1752
1753	/* Enable TX and RX */
1754	macb_writel(bp, NCR, MACB_BIT(RE) | MACB_BIT(TE) | MACB_BIT(MPE));
1755}
1756
1757/* The hash address register is 64 bits long and takes up two
1758 * locations in the memory map.  The least significant bits are stored
1759 * in EMAC_HSL and the most significant bits in EMAC_HSH.
1760 *
1761 * The unicast hash enable and the multicast hash enable bits in the
1762 * network configuration register enable the reception of hash matched
1763 * frames. The destination address is reduced to a 6 bit index into
1764 * the 64 bit hash register using the following hash function.  The
1765 * hash function is an exclusive or of every sixth bit of the
1766 * destination address.
1767 *
1768 * hi[5] = da[5] ^ da[11] ^ da[17] ^ da[23] ^ da[29] ^ da[35] ^ da[41] ^ da[47]
1769 * hi[4] = da[4] ^ da[10] ^ da[16] ^ da[22] ^ da[28] ^ da[34] ^ da[40] ^ da[46]
1770 * hi[3] = da[3] ^ da[09] ^ da[15] ^ da[21] ^ da[27] ^ da[33] ^ da[39] ^ da[45]
1771 * hi[2] = da[2] ^ da[08] ^ da[14] ^ da[20] ^ da[26] ^ da[32] ^ da[38] ^ da[44]
1772 * hi[1] = da[1] ^ da[07] ^ da[13] ^ da[19] ^ da[25] ^ da[31] ^ da[37] ^ da[43]
1773 * hi[0] = da[0] ^ da[06] ^ da[12] ^ da[18] ^ da[24] ^ da[30] ^ da[36] ^ da[42]
1774 *
1775 * da[0] represents the least significant bit of the first byte
1776 * received, that is, the multicast/unicast indicator, and da[47]
1777 * represents the most significant bit of the last byte received.  If
1778 * the hash index, hi[n], points to a bit that is set in the hash
1779 * register then the frame will be matched according to whether the
1780 * frame is multicast or unicast.  A multicast match will be signalled
1781 * if the multicast hash enable bit is set, da[0] is 1 and the hash
1782 * index points to a bit set in the hash register.  A unicast match
1783 * will be signalled if the unicast hash enable bit is set, da[0] is 0
1784 * and the hash index points to a bit set in the hash register.  To
1785 * receive all multicast frames, the hash register should be set with
1786 * all ones and the multicast hash enable bit should be set in the
1787 * network configuration register.
1788 */
1789
1790static inline int hash_bit_value(int bitnr, __u8 *addr)
1791{
1792	if (addr[bitnr / 8] & (1 << (bitnr % 8)))
1793		return 1;
1794	return 0;
1795}
1796
1797/* Return the hash index value for the specified address. */
1798static int hash_get_index(__u8 *addr)
1799{
1800	int i, j, bitval;
1801	int hash_index = 0;
1802
1803	for (j = 0; j < 6; j++) {
1804		for (i = 0, bitval = 0; i < 8; i++)
1805			bitval ^= hash_bit_value(i * 6 + j, addr);
1806
1807		hash_index |= (bitval << j);
1808	}
1809
1810	return hash_index;
1811}
1812
1813/* Add multicast addresses to the internal multicast-hash table. */
1814static void macb_sethashtable(struct net_device *dev)
1815{
1816	struct netdev_hw_addr *ha;
1817	unsigned long mc_filter[2];
1818	unsigned int bitnr;
1819	struct macb *bp = netdev_priv(dev);
1820
1821	mc_filter[0] = 0;
1822	mc_filter[1] = 0;
1823
1824	netdev_for_each_mc_addr(ha, dev) {
1825		bitnr = hash_get_index(ha->addr);
1826		mc_filter[bitnr >> 5] |= 1 << (bitnr & 31);
1827	}
1828
1829	macb_or_gem_writel(bp, HRB, mc_filter[0]);
1830	macb_or_gem_writel(bp, HRT, mc_filter[1]);
1831}
1832
1833/* Enable/Disable promiscuous and multicast modes. */
1834static void macb_set_rx_mode(struct net_device *dev)
1835{
1836	unsigned long cfg;
1837	struct macb *bp = netdev_priv(dev);
1838
1839	cfg = macb_readl(bp, NCFGR);
1840
1841	if (dev->flags & IFF_PROMISC) {
1842		/* Enable promiscuous mode */
1843		cfg |= MACB_BIT(CAF);
1844
1845		/* Disable RX checksum offload */
1846		if (macb_is_gem(bp))
1847			cfg &= ~GEM_BIT(RXCOEN);
1848	} else {
1849		/* Disable promiscuous mode */
1850		cfg &= ~MACB_BIT(CAF);
1851
1852		/* Enable RX checksum offload only if requested */
1853		if (macb_is_gem(bp) && dev->features & NETIF_F_RXCSUM)
1854			cfg |= GEM_BIT(RXCOEN);
1855	}
1856
1857	if (dev->flags & IFF_ALLMULTI) {
1858		/* Enable all multicast mode */
1859		macb_or_gem_writel(bp, HRB, -1);
1860		macb_or_gem_writel(bp, HRT, -1);
1861		cfg |= MACB_BIT(NCFGR_MTI);
1862	} else if (!netdev_mc_empty(dev)) {
1863		/* Enable specific multicasts */
1864		macb_sethashtable(dev);
1865		cfg |= MACB_BIT(NCFGR_MTI);
1866	} else if (dev->flags & (~IFF_ALLMULTI)) {
1867		/* Disable all multicast mode */
1868		macb_or_gem_writel(bp, HRB, 0);
1869		macb_or_gem_writel(bp, HRT, 0);
1870		cfg &= ~MACB_BIT(NCFGR_MTI);
1871	}
1872
1873	macb_writel(bp, NCFGR, cfg);
1874}
1875
1876static int macb_open(struct net_device *dev)
1877{
1878	struct macb *bp = netdev_priv(dev);
1879	size_t bufsz = dev->mtu + ETH_HLEN + ETH_FCS_LEN + NET_IP_ALIGN;
1880	int err;
1881
1882	netdev_dbg(bp->dev, "open\n");
1883
1884	/* carrier starts down */
1885	netif_carrier_off(dev);
1886
1887	/* if the phy is not yet register, retry later*/
1888	if (!dev->phydev)
1889		return -EAGAIN;
1890
1891	/* RX buffers initialization */
1892	macb_init_rx_buffer_size(bp, bufsz);
1893
1894	err = macb_alloc_consistent(bp);
1895	if (err) {
1896		netdev_err(dev, "Unable to allocate DMA memory (error %d)\n",
1897			   err);
1898		return err;
1899	}
1900
1901	napi_enable(&bp->napi);
1902
1903	bp->macbgem_ops.mog_init_rings(bp);
1904	macb_init_hw(bp);
1905
1906	/* schedule a link state check */
1907	phy_start(dev->phydev);
1908
1909	netif_tx_start_all_queues(dev);
1910
1911	return 0;
1912}
1913
1914static int macb_close(struct net_device *dev)
1915{
1916	struct macb *bp = netdev_priv(dev);
1917	unsigned long flags;
1918
1919	netif_tx_stop_all_queues(dev);
1920	napi_disable(&bp->napi);
1921
1922	if (dev->phydev)
1923		phy_stop(dev->phydev);
1924
1925	spin_lock_irqsave(&bp->lock, flags);
1926	macb_reset_hw(bp);
1927	netif_carrier_off(dev);
1928	spin_unlock_irqrestore(&bp->lock, flags);
1929
1930	macb_free_consistent(bp);
1931
1932	return 0;
1933}
1934
1935static int macb_change_mtu(struct net_device *dev, int new_mtu)
1936{
1937	struct macb *bp = netdev_priv(dev);
1938	u32 max_mtu;
1939
1940	if (netif_running(dev))
1941		return -EBUSY;
1942
1943	max_mtu = ETH_DATA_LEN;
1944	if (bp->caps & MACB_CAPS_JUMBO)
1945		max_mtu = gem_readl(bp, JML) - ETH_HLEN - ETH_FCS_LEN;
1946
1947	if ((new_mtu > max_mtu) || (new_mtu < GEM_MTU_MIN_SIZE))
1948		return -EINVAL;
1949
1950	dev->mtu = new_mtu;
1951
1952	return 0;
1953}
1954
1955static void gem_update_stats(struct macb *bp)
1956{
1957	unsigned int i;
1958	u32 *p = &bp->hw_stats.gem.tx_octets_31_0;
1959
1960	for (i = 0; i < GEM_STATS_LEN; ++i, ++p) {
1961		u32 offset = gem_statistics[i].offset;
1962		u64 val = bp->macb_reg_readl(bp, offset);
1963
1964		bp->ethtool_stats[i] += val;
1965		*p += val;
1966
1967		if (offset == GEM_OCTTXL || offset == GEM_OCTRXL) {
1968			/* Add GEM_OCTTXH, GEM_OCTRXH */
1969			val = bp->macb_reg_readl(bp, offset + 4);
1970			bp->ethtool_stats[i] += ((u64)val) << 32;
1971			*(++p) += val;
1972		}
1973	}
1974}
1975
1976static struct net_device_stats *gem_get_stats(struct macb *bp)
1977{
1978	struct gem_stats *hwstat = &bp->hw_stats.gem;
1979	struct net_device_stats *nstat = &bp->stats;
1980
1981	gem_update_stats(bp);
1982
1983	nstat->rx_errors = (hwstat->rx_frame_check_sequence_errors +
1984			    hwstat->rx_alignment_errors +
1985			    hwstat->rx_resource_errors +
1986			    hwstat->rx_overruns +
1987			    hwstat->rx_oversize_frames +
1988			    hwstat->rx_jabbers +
1989			    hwstat->rx_undersized_frames +
1990			    hwstat->rx_length_field_frame_errors);
1991	nstat->tx_errors = (hwstat->tx_late_collisions +
1992			    hwstat->tx_excessive_collisions +
1993			    hwstat->tx_underrun +
1994			    hwstat->tx_carrier_sense_errors);
1995	…