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   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Copyright (C) 1999 - 2010 Intel Corporation.
   4 * Copyright (C) 2010 LAPIS SEMICONDUCTOR CO., LTD.
   5 */
   6
   7#include <linux/interrupt.h>
   8#include <linux/delay.h>
   9#include <linux/io.h>
  10#include <linux/module.h>
  11#include <linux/sched.h>
  12#include <linux/pci.h>
  13#include <linux/kernel.h>
  14#include <linux/types.h>
  15#include <linux/errno.h>
  16#include <linux/netdevice.h>
  17#include <linux/skbuff.h>
  18#include <linux/can.h>
  19#include <linux/can/dev.h>
  20#include <linux/can/error.h>
  21
  22#define PCH_CTRL_INIT		BIT(0) /* The INIT bit of CANCONT register. */
  23#define PCH_CTRL_IE		BIT(1) /* The IE bit of CAN control register */
  24#define PCH_CTRL_IE_SIE_EIE	(BIT(3) | BIT(2) | BIT(1))
  25#define PCH_CTRL_CCE		BIT(6)
  26#define PCH_CTRL_OPT		BIT(7) /* The OPT bit of CANCONT register. */
  27#define PCH_OPT_SILENT		BIT(3) /* The Silent bit of CANOPT reg. */
  28#define PCH_OPT_LBACK		BIT(4) /* The LoopBack bit of CANOPT reg. */
  29
  30#define PCH_CMASK_RX_TX_SET	0x00f3
  31#define PCH_CMASK_RX_TX_GET	0x0073
  32#define PCH_CMASK_ALL		0xff
  33#define PCH_CMASK_NEWDAT	BIT(2)
  34#define PCH_CMASK_CLRINTPND	BIT(3)
  35#define PCH_CMASK_CTRL		BIT(4)
  36#define PCH_CMASK_ARB		BIT(5)
  37#define PCH_CMASK_MASK		BIT(6)
  38#define PCH_CMASK_RDWR		BIT(7)
  39#define PCH_IF_MCONT_NEWDAT	BIT(15)
  40#define PCH_IF_MCONT_MSGLOST	BIT(14)
  41#define PCH_IF_MCONT_INTPND	BIT(13)
  42#define PCH_IF_MCONT_UMASK	BIT(12)
  43#define PCH_IF_MCONT_TXIE	BIT(11)
  44#define PCH_IF_MCONT_RXIE	BIT(10)
  45#define PCH_IF_MCONT_RMTEN	BIT(9)
  46#define PCH_IF_MCONT_TXRQXT	BIT(8)
  47#define PCH_IF_MCONT_EOB	BIT(7)
  48#define PCH_IF_MCONT_DLC	(BIT(0) | BIT(1) | BIT(2) | BIT(3))
  49#define PCH_MASK2_MDIR_MXTD	(BIT(14) | BIT(15))
  50#define PCH_ID2_DIR		BIT(13)
  51#define PCH_ID2_XTD		BIT(14)
  52#define PCH_ID_MSGVAL		BIT(15)
  53#define PCH_IF_CREQ_BUSY	BIT(15)
  54
  55#define PCH_STATUS_INT		0x8000
  56#define PCH_RP			0x00008000
  57#define PCH_REC			0x00007f00
  58#define PCH_TEC			0x000000ff
  59
  60#define PCH_TX_OK		BIT(3)
  61#define PCH_RX_OK		BIT(4)
  62#define PCH_EPASSIV		BIT(5)
  63#define PCH_EWARN		BIT(6)
  64#define PCH_BUS_OFF		BIT(7)
  65
  66/* bit position of certain controller bits. */
  67#define PCH_BIT_BRP_SHIFT	0
  68#define PCH_BIT_SJW_SHIFT	6
  69#define PCH_BIT_TSEG1_SHIFT	8
  70#define PCH_BIT_TSEG2_SHIFT	12
  71#define PCH_BIT_BRPE_BRPE_SHIFT	6
  72
  73#define PCH_MSK_BITT_BRP	0x3f
  74#define PCH_MSK_BRPE_BRPE	0x3c0
  75#define PCH_MSK_CTRL_IE_SIE_EIE	0x07
  76#define PCH_COUNTER_LIMIT	10
  77
  78#define PCH_CAN_CLK		50000000	/* 50MHz */
  79
  80/*
  81 * Define the number of message object.
  82 * PCH CAN communications are done via Message RAM.
  83 * The Message RAM consists of 32 message objects.
  84 */
  85#define PCH_RX_OBJ_NUM		26
  86#define PCH_TX_OBJ_NUM		6
  87#define PCH_RX_OBJ_START	1
  88#define PCH_RX_OBJ_END		PCH_RX_OBJ_NUM
  89#define PCH_TX_OBJ_START	(PCH_RX_OBJ_END + 1)
  90#define PCH_TX_OBJ_END		(PCH_RX_OBJ_NUM + PCH_TX_OBJ_NUM)
  91
  92#define PCH_FIFO_THRESH		16
  93
  94/* TxRqst2 show status of MsgObjNo.17~32 */
  95#define PCH_TREQ2_TX_MASK	(((1 << PCH_TX_OBJ_NUM) - 1) <<\
  96							(PCH_RX_OBJ_END - 16))
  97
  98enum pch_ifreg {
  99	PCH_RX_IFREG,
 100	PCH_TX_IFREG,
 101};
 102
 103enum pch_can_err {
 104	PCH_STUF_ERR = 1,
 105	PCH_FORM_ERR,
 106	PCH_ACK_ERR,
 107	PCH_BIT1_ERR,
 108	PCH_BIT0_ERR,
 109	PCH_CRC_ERR,
 110	PCH_LEC_ALL,
 111};
 112
 113enum pch_can_mode {
 114	PCH_CAN_ENABLE,
 115	PCH_CAN_DISABLE,
 116	PCH_CAN_ALL,
 117	PCH_CAN_NONE,
 118	PCH_CAN_STOP,
 119	PCH_CAN_RUN,
 120};
 121
 122struct pch_can_if_regs {
 123	u32 creq;
 124	u32 cmask;
 125	u32 mask1;
 126	u32 mask2;
 127	u32 id1;
 128	u32 id2;
 129	u32 mcont;
 130	u32 data[4];
 131	u32 rsv[13];
 132};
 133
 134struct pch_can_regs {
 135	u32 cont;
 136	u32 stat;
 137	u32 errc;
 138	u32 bitt;
 139	u32 intr;
 140	u32 opt;
 141	u32 brpe;
 142	u32 reserve;
 143	struct pch_can_if_regs ifregs[2]; /* [0]=if1  [1]=if2 */
 144	u32 reserve1[8];
 145	u32 treq1;
 146	u32 treq2;
 147	u32 reserve2[6];
 148	u32 data1;
 149	u32 data2;
 150	u32 reserve3[6];
 151	u32 canipend1;
 152	u32 canipend2;
 153	u32 reserve4[6];
 154	u32 canmval1;
 155	u32 canmval2;
 156	u32 reserve5[37];
 157	u32 srst;
 158};
 159
 160struct pch_can_priv {
 161	struct can_priv can;
 162	struct pci_dev *dev;
 163	u32 tx_enable[PCH_TX_OBJ_END];
 164	u32 rx_enable[PCH_TX_OBJ_END];
 165	u32 rx_link[PCH_TX_OBJ_END];
 166	u32 int_enables;
 167	struct net_device *ndev;
 168	struct pch_can_regs __iomem *regs;
 169	struct napi_struct napi;
 170	int tx_obj;	/* Point next Tx Obj index */
 171	int use_msi;
 172};
 173
 174static const struct can_bittiming_const pch_can_bittiming_const = {
 175	.name = KBUILD_MODNAME,
 176	.tseg1_min = 2,
 177	.tseg1_max = 16,
 178	.tseg2_min = 1,
 179	.tseg2_max = 8,
 180	.sjw_max = 4,
 181	.brp_min = 1,
 182	.brp_max = 1024, /* 6bit + extended 4bit */
 183	.brp_inc = 1,
 184};
 185
 186static const struct pci_device_id pch_pci_tbl[] = {
 187	{PCI_VENDOR_ID_INTEL, 0x8818, PCI_ANY_ID, PCI_ANY_ID,},
 188	{0,}
 189};
 190MODULE_DEVICE_TABLE(pci, pch_pci_tbl);
 191
 192static inline void pch_can_bit_set(void __iomem *addr, u32 mask)
 193{
 194	iowrite32(ioread32(addr) | mask, addr);
 195}
 196
 197static inline void pch_can_bit_clear(void __iomem *addr, u32 mask)
 198{
 199	iowrite32(ioread32(addr) & ~mask, addr);
 200}
 201
 202static void pch_can_set_run_mode(struct pch_can_priv *priv,
 203				 enum pch_can_mode mode)
 204{
 205	switch (mode) {
 206	case PCH_CAN_RUN:
 207		pch_can_bit_clear(&priv->regs->cont, PCH_CTRL_INIT);
 208		break;
 209
 210	case PCH_CAN_STOP:
 211		pch_can_bit_set(&priv->regs->cont, PCH_CTRL_INIT);
 212		break;
 213
 214	default:
 215		netdev_err(priv->ndev, "%s -> Invalid Mode.\n", __func__);
 216		break;
 217	}
 218}
 219
 220static void pch_can_set_optmode(struct pch_can_priv *priv)
 221{
 222	u32 reg_val = ioread32(&priv->regs->opt);
 223
 224	if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
 225		reg_val |= PCH_OPT_SILENT;
 226
 227	if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
 228		reg_val |= PCH_OPT_LBACK;
 229
 230	pch_can_bit_set(&priv->regs->cont, PCH_CTRL_OPT);
 231	iowrite32(reg_val, &priv->regs->opt);
 232}
 233
 234static void pch_can_rw_msg_obj(void __iomem *creq_addr, u32 num)
 235{
 236	int counter = PCH_COUNTER_LIMIT;
 237	u32 ifx_creq;
 238
 239	iowrite32(num, creq_addr);
 240	while (counter) {
 241		ifx_creq = ioread32(creq_addr) & PCH_IF_CREQ_BUSY;
 242		if (!ifx_creq)
 243			break;
 244		counter--;
 245		udelay(1);
 246	}
 247	if (!counter)
 248		pr_err("%s:IF1 BUSY Flag is set forever.\n", __func__);
 249}
 250
 251static void pch_can_set_int_enables(struct pch_can_priv *priv,
 252				    enum pch_can_mode interrupt_no)
 253{
 254	switch (interrupt_no) {
 255	case PCH_CAN_DISABLE:
 256		pch_can_bit_clear(&priv->regs->cont, PCH_CTRL_IE);
 257		break;
 258
 259	case PCH_CAN_ALL:
 260		pch_can_bit_set(&priv->regs->cont, PCH_CTRL_IE_SIE_EIE);
 261		break;
 262
 263	case PCH_CAN_NONE:
 264		pch_can_bit_clear(&priv->regs->cont, PCH_CTRL_IE_SIE_EIE);
 265		break;
 266
 267	default:
 268		netdev_err(priv->ndev, "Invalid interrupt number.\n");
 269		break;
 270	}
 271}
 272
 273static void pch_can_set_rxtx(struct pch_can_priv *priv, u32 buff_num,
 274			     int set, enum pch_ifreg dir)
 275{
 276	u32 ie;
 277
 278	if (dir)
 279		ie = PCH_IF_MCONT_TXIE;
 280	else
 281		ie = PCH_IF_MCONT_RXIE;
 282
 283	/* Reading the Msg buffer from Message RAM to IF1/2 registers. */
 284	iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[dir].cmask);
 285	pch_can_rw_msg_obj(&priv->regs->ifregs[dir].creq, buff_num);
 286
 287	/* Setting the IF1/2MASK1 register to access MsgVal and RxIE bits */
 288	iowrite32(PCH_CMASK_RDWR | PCH_CMASK_ARB | PCH_CMASK_CTRL,
 289		  &priv->regs->ifregs[dir].cmask);
 290
 291	if (set) {
 292		/* Setting the MsgVal and RxIE/TxIE bits */
 293		pch_can_bit_set(&priv->regs->ifregs[dir].mcont, ie);
 294		pch_can_bit_set(&priv->regs->ifregs[dir].id2, PCH_ID_MSGVAL);
 295	} else {
 296		/* Clearing the MsgVal and RxIE/TxIE bits */
 297		pch_can_bit_clear(&priv->regs->ifregs[dir].mcont, ie);
 298		pch_can_bit_clear(&priv->regs->ifregs[dir].id2, PCH_ID_MSGVAL);
 299	}
 300
 301	pch_can_rw_msg_obj(&priv->regs->ifregs[dir].creq, buff_num);
 302}
 303
 304static void pch_can_set_rx_all(struct pch_can_priv *priv, int set)
 305{
 306	int i;
 307
 308	/* Traversing to obtain the object configured as receivers. */
 309	for (i = PCH_RX_OBJ_START; i <= PCH_RX_OBJ_END; i++)
 310		pch_can_set_rxtx(priv, i, set, PCH_RX_IFREG);
 311}
 312
 313static void pch_can_set_tx_all(struct pch_can_priv *priv, int set)
 314{
 315	int i;
 316
 317	/* Traversing to obtain the object configured as transmit object. */
 318	for (i = PCH_TX_OBJ_START; i <= PCH_TX_OBJ_END; i++)
 319		pch_can_set_rxtx(priv, i, set, PCH_TX_IFREG);
 320}
 321
 322static u32 pch_can_int_pending(struct pch_can_priv *priv)
 323{
 324	return ioread32(&priv->regs->intr) & 0xffff;
 325}
 326
 327static void pch_can_clear_if_buffers(struct pch_can_priv *priv)
 328{
 329	int i; /* Msg Obj ID (1~32) */
 330
 331	for (i = PCH_RX_OBJ_START; i <= PCH_TX_OBJ_END; i++) {
 332		iowrite32(PCH_CMASK_RX_TX_SET, &priv->regs->ifregs[0].cmask);
 333		iowrite32(0xffff, &priv->regs->ifregs[0].mask1);
 334		iowrite32(0xffff, &priv->regs->ifregs[0].mask2);
 335		iowrite32(0x0, &priv->regs->ifregs[0].id1);
 336		iowrite32(0x0, &priv->regs->ifregs[0].id2);
 337		iowrite32(0x0, &priv->regs->ifregs[0].mcont);
 338		iowrite32(0x0, &priv->regs->ifregs[0].data[0]);
 339		iowrite32(0x0, &priv->regs->ifregs[0].data[1]);
 340		iowrite32(0x0, &priv->regs->ifregs[0].data[2]);
 341		iowrite32(0x0, &priv->regs->ifregs[0].data[3]);
 342		iowrite32(PCH_CMASK_RDWR | PCH_CMASK_MASK |
 343			  PCH_CMASK_ARB | PCH_CMASK_CTRL,
 344			  &priv->regs->ifregs[0].cmask);
 345		pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, i);
 346	}
 347}
 348
 349static void pch_can_config_rx_tx_buffers(struct pch_can_priv *priv)
 350{
 351	int i;
 352
 353	for (i = PCH_RX_OBJ_START; i <= PCH_RX_OBJ_END; i++) {
 354		iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[0].cmask);
 355		pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, i);
 356
 357		iowrite32(0x0, &priv->regs->ifregs[0].id1);
 358		iowrite32(0x0, &priv->regs->ifregs[0].id2);
 359
 360		pch_can_bit_set(&priv->regs->ifregs[0].mcont,
 361				PCH_IF_MCONT_UMASK);
 362
 363		/* In case FIFO mode, Last EoB of Rx Obj must be 1 */
 364		if (i == PCH_RX_OBJ_END)
 365			pch_can_bit_set(&priv->regs->ifregs[0].mcont,
 366					PCH_IF_MCONT_EOB);
 367		else
 368			pch_can_bit_clear(&priv->regs->ifregs[0].mcont,
 369					  PCH_IF_MCONT_EOB);
 370
 371		iowrite32(0, &priv->regs->ifregs[0].mask1);
 372		pch_can_bit_clear(&priv->regs->ifregs[0].mask2,
 373				  0x1fff | PCH_MASK2_MDIR_MXTD);
 374
 375		/* Setting CMASK for writing */
 376		iowrite32(PCH_CMASK_RDWR | PCH_CMASK_MASK | PCH_CMASK_ARB |
 377			  PCH_CMASK_CTRL, &priv->regs->ifregs[0].cmask);
 378
 379		pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, i);
 380	}
 381
 382	for (i = PCH_TX_OBJ_START; i <= PCH_TX_OBJ_END; i++) {
 383		iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[1].cmask);
 384		pch_can_rw_msg_obj(&priv->regs->ifregs[1].creq, i);
 385
 386		/* Resetting DIR bit for reception */
 387		iowrite32(0x0, &priv->regs->ifregs[1].id1);
 388		iowrite32(PCH_ID2_DIR, &priv->regs->ifregs[1].id2);
 389
 390		/* Setting EOB bit for transmitter */
 391		iowrite32(PCH_IF_MCONT_EOB | PCH_IF_MCONT_UMASK,
 392			  &priv->regs->ifregs[1].mcont);
 393
 394		iowrite32(0, &priv->regs->ifregs[1].mask1);
 395		pch_can_bit_clear(&priv->regs->ifregs[1].mask2, 0x1fff);
 396
 397		/* Setting CMASK for writing */
 398		iowrite32(PCH_CMASK_RDWR | PCH_CMASK_MASK | PCH_CMASK_ARB |
 399			  PCH_CMASK_CTRL, &priv->regs->ifregs[1].cmask);
 400
 401		pch_can_rw_msg_obj(&priv->regs->ifregs[1].creq, i);
 402	}
 403}
 404
 405static void pch_can_init(struct pch_can_priv *priv)
 406{
 407	/* Stopping the Can device. */
 408	pch_can_set_run_mode(priv, PCH_CAN_STOP);
 409
 410	/* Clearing all the message object buffers. */
 411	pch_can_clear_if_buffers(priv);
 412
 413	/* Configuring the respective message object as either rx/tx object. */
 414	pch_can_config_rx_tx_buffers(priv);
 415
 416	/* Enabling the interrupts. */
 417	pch_can_set_int_enables(priv, PCH_CAN_ALL);
 418}
 419
 420static void pch_can_release(struct pch_can_priv *priv)
 421{
 422	/* Stooping the CAN device. */
 423	pch_can_set_run_mode(priv, PCH_CAN_STOP);
 424
 425	/* Disabling the interrupts. */
 426	pch_can_set_int_enables(priv, PCH_CAN_NONE);
 427
 428	/* Disabling all the receive object. */
 429	pch_can_set_rx_all(priv, 0);
 430
 431	/* Disabling all the transmit object. */
 432	pch_can_set_tx_all(priv, 0);
 433}
 434
 435/* This function clears interrupt(s) from the CAN device. */
 436static void pch_can_int_clr(struct pch_can_priv *priv, u32 mask)
 437{
 438	/* Clear interrupt for transmit object */
 439	if ((mask >= PCH_RX_OBJ_START) && (mask <= PCH_RX_OBJ_END)) {
 440		/* Setting CMASK for clearing the reception interrupts. */
 441		iowrite32(PCH_CMASK_RDWR | PCH_CMASK_CTRL | PCH_CMASK_ARB,
 442			  &priv->regs->ifregs[0].cmask);
 443
 444		/* Clearing the Dir bit. */
 445		pch_can_bit_clear(&priv->regs->ifregs[0].id2, PCH_ID2_DIR);
 446
 447		/* Clearing NewDat & IntPnd */
 448		pch_can_bit_clear(&priv->regs->ifregs[0].mcont,
 449				  PCH_IF_MCONT_NEWDAT | PCH_IF_MCONT_INTPND);
 450
 451		pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, mask);
 452	} else if ((mask >= PCH_TX_OBJ_START) && (mask <= PCH_TX_OBJ_END)) {
 453		/*
 454		 * Setting CMASK for clearing interrupts for frame transmission.
 455		 */
 456		iowrite32(PCH_CMASK_RDWR | PCH_CMASK_CTRL | PCH_CMASK_ARB,
 457			  &priv->regs->ifregs[1].cmask);
 458
 459		/* Resetting the ID registers. */
 460		pch_can_bit_set(&priv->regs->ifregs[1].id2,
 461			       PCH_ID2_DIR | (0x7ff << 2));
 462		iowrite32(0x0, &priv->regs->ifregs[1].id1);
 463
 464		/* Clearing NewDat, TxRqst & IntPnd */
 465		pch_can_bit_clear(&priv->regs->ifregs[1].mcont,
 466				  PCH_IF_MCONT_NEWDAT | PCH_IF_MCONT_INTPND |
 467				  PCH_IF_MCONT_TXRQXT);
 468		pch_can_rw_msg_obj(&priv->regs->ifregs[1].creq, mask);
 469	}
 470}
 471
 472static void pch_can_reset(struct pch_can_priv *priv)
 473{
 474	/* write to sw reset register */
 475	iowrite32(1, &priv->regs->srst);
 476	iowrite32(0, &priv->regs->srst);
 477}
 478
 479static void pch_can_error(struct net_device *ndev, u32 status)
 480{
 481	struct sk_buff *skb;
 482	struct pch_can_priv *priv = netdev_priv(ndev);
 483	struct can_frame *cf;
 484	u32 errc, lec;
 485	struct net_device_stats *stats = &(priv->ndev->stats);
 486	enum can_state state = priv->can.state;
 487
 488	skb = alloc_can_err_skb(ndev, &cf);
 489	if (!skb)
 490		return;
 491
 492	if (status & PCH_BUS_OFF) {
 493		pch_can_set_tx_all(priv, 0);
 494		pch_can_set_rx_all(priv, 0);
 495		state = CAN_STATE_BUS_OFF;
 496		cf->can_id |= CAN_ERR_BUSOFF;
 497		priv->can.can_stats.bus_off++;
 498		can_bus_off(ndev);
 499	}
 500
 501	errc = ioread32(&priv->regs->errc);
 502	/* Warning interrupt. */
 503	if (status & PCH_EWARN) {
 504		state = CAN_STATE_ERROR_WARNING;
 505		priv->can.can_stats.error_warning++;
 506		cf->can_id |= CAN_ERR_CRTL;
 507		if (((errc & PCH_REC) >> 8) > 96)
 508			cf->data[1] |= CAN_ERR_CRTL_RX_WARNING;
 509		if ((errc & PCH_TEC) > 96)
 510			cf->data[1] |= CAN_ERR_CRTL_TX_WARNING;
 511		netdev_dbg(ndev,
 512			"%s -> Error Counter is more than 96.\n", __func__);
 513	}
 514	/* Error passive interrupt. */
 515	if (status & PCH_EPASSIV) {
 516		priv->can.can_stats.error_passive++;
 517		state = CAN_STATE_ERROR_PASSIVE;
 518		cf->can_id |= CAN_ERR_CRTL;
 519		if (errc & PCH_RP)
 520			cf->data[1] |= CAN_ERR_CRTL_RX_PASSIVE;
 521		if ((errc & PCH_TEC) > 127)
 522			cf->data[1] |= CAN_ERR_CRTL_TX_PASSIVE;
 523		netdev_dbg(ndev,
 524			"%s -> CAN controller is ERROR PASSIVE .\n", __func__);
 525	}
 526
 527	lec = status & PCH_LEC_ALL;
 528	switch (lec) {
 529	case PCH_STUF_ERR:
 530		cf->data[2] |= CAN_ERR_PROT_STUFF;
 531		priv->can.can_stats.bus_error++;
 532		stats->rx_errors++;
 533		break;
 534	case PCH_FORM_ERR:
 535		cf->data[2] |= CAN_ERR_PROT_FORM;
 536		priv->can.can_stats.bus_error++;
 537		stats->rx_errors++;
 538		break;
 539	case PCH_ACK_ERR:
 540		cf->can_id |= CAN_ERR_ACK;
 541		priv->can.can_stats.bus_error++;
 542		stats->rx_errors++;
 543		break;
 544	case PCH_BIT1_ERR:
 545	case PCH_BIT0_ERR:
 546		cf->data[2] |= CAN_ERR_PROT_BIT;
 547		priv->can.can_stats.bus_error++;
 548		stats->rx_errors++;
 549		break;
 550	case PCH_CRC_ERR:
 551		cf->data[3] = CAN_ERR_PROT_LOC_CRC_SEQ;
 552		priv->can.can_stats.bus_error++;
 553		stats->rx_errors++;
 554		break;
 555	case PCH_LEC_ALL: /* Written by CPU. No error status */
 556		break;
 557	}
 558
 559	cf->data[6] = errc & PCH_TEC;
 560	cf->data[7] = (errc & PCH_REC) >> 8;
 561
 562	priv->can.state = state;
 563	netif_receive_skb(skb);
 564
 565	stats->rx_packets++;
 566	stats->rx_bytes += cf->len;
 567}
 568
 569static irqreturn_t pch_can_interrupt(int irq, void *dev_id)
 570{
 571	struct net_device *ndev = (struct net_device *)dev_id;
 572	struct pch_can_priv *priv = netdev_priv(ndev);
 573
 574	if (!pch_can_int_pending(priv))
 575		return IRQ_NONE;
 576
 577	pch_can_set_int_enables(priv, PCH_CAN_NONE);
 578	napi_schedule(&priv->napi);
 579	return IRQ_HANDLED;
 580}
 581
 582static void pch_fifo_thresh(struct pch_can_priv *priv, int obj_id)
 583{
 584	if (obj_id < PCH_FIFO_THRESH) {
 585		iowrite32(PCH_CMASK_RDWR | PCH_CMASK_CTRL |
 586			  PCH_CMASK_ARB, &priv->regs->ifregs[0].cmask);
 587
 588		/* Clearing the Dir bit. */
 589		pch_can_bit_clear(&priv->regs->ifregs[0].id2, PCH_ID2_DIR);
 590
 591		/* Clearing NewDat & IntPnd */
 592		pch_can_bit_clear(&priv->regs->ifregs[0].mcont,
 593				  PCH_IF_MCONT_INTPND);
 594		pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, obj_id);
 595	} else if (obj_id > PCH_FIFO_THRESH) {
 596		pch_can_int_clr(priv, obj_id);
 597	} else if (obj_id == PCH_FIFO_THRESH) {
 598		int cnt;
 599		for (cnt = 0; cnt < PCH_FIFO_THRESH; cnt++)
 600			pch_can_int_clr(priv, cnt + 1);
 601	}
 602}
 603
 604static void pch_can_rx_msg_lost(struct net_device *ndev, int obj_id)
 605{
 606	struct pch_can_priv *priv = netdev_priv(ndev);
 607	struct net_device_stats *stats = &(priv->ndev->stats);
 608	struct sk_buff *skb;
 609	struct can_frame *cf;
 610
 611	netdev_dbg(priv->ndev, "Msg Obj is overwritten.\n");
 612	pch_can_bit_clear(&priv->regs->ifregs[0].mcont,
 613			  PCH_IF_MCONT_MSGLOST);
 614	iowrite32(PCH_CMASK_RDWR | PCH_CMASK_CTRL,
 615		  &priv->regs->ifregs[0].cmask);
 616	pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, obj_id);
 617
 618	skb = alloc_can_err_skb(ndev, &cf);
 619	if (!skb)
 620		return;
 621
 622	cf->can_id |= CAN_ERR_CRTL;
 623	cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
 624	stats->rx_over_errors++;
 625	stats->rx_errors++;
 626
 627	netif_receive_skb(skb);
 628}
 629
 630static int pch_can_rx_normal(struct net_device *ndev, u32 obj_num, int quota)
 631{
 632	u32 reg;
 633	canid_t id;
 634	int rcv_pkts = 0;
 635	struct sk_buff *skb;
 636	struct can_frame *cf;
 637	struct pch_can_priv *priv = netdev_priv(ndev);
 638	struct net_device_stats *stats = &(priv->ndev->stats);
 639	int i;
 640	u32 id2;
 641	u16 data_reg;
 642
 643	do {
 644		/* Reading the message object from the Message RAM */
 645		iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[0].cmask);
 646		pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, obj_num);
 647
 648		/* Reading the MCONT register. */
 649		reg = ioread32(&priv->regs->ifregs[0].mcont);
 650
 651		if (reg & PCH_IF_MCONT_EOB)
 652			break;
 653
 654		/* If MsgLost bit set. */
 655		if (reg & PCH_IF_MCONT_MSGLOST) {
 656			pch_can_rx_msg_lost(ndev, obj_num);
 657			rcv_pkts++;
 658			quota--;
 659			obj_num++;
 660			continue;
 661		} else if (!(reg & PCH_IF_MCONT_NEWDAT)) {
 662			obj_num++;
 663			continue;
 664		}
 665
 666		skb = alloc_can_skb(priv->ndev, &cf);
 667		if (!skb) {
 668			netdev_err(ndev, "alloc_can_skb Failed\n");
 669			return rcv_pkts;
 670		}
 671
 672		/* Get Received data */
 673		id2 = ioread32(&priv->regs->ifregs[0].id2);
 674		if (id2 & PCH_ID2_XTD) {
 675			id = (ioread32(&priv->regs->ifregs[0].id1) & 0xffff);
 676			id |= (((id2) & 0x1fff) << 16);
 677			cf->can_id = id | CAN_EFF_FLAG;
 678		} else {
 679			id = (id2 >> 2) & CAN_SFF_MASK;
 680			cf->can_id = id;
 681		}
 682
 683		if (id2 & PCH_ID2_DIR)
 684			cf->can_id |= CAN_RTR_FLAG;
 685
 686		cf->len = can_cc_dlc2len((ioread32(&priv->regs->
 687						    ifregs[0].mcont)) & 0xF);
 688
 689		for (i = 0; i < cf->len; i += 2) {
 690			data_reg = ioread16(&priv->regs->ifregs[0].data[i / 2]);
 691			cf->data[i] = data_reg;
 692			cf->data[i + 1] = data_reg >> 8;
 693		}
 694
 695		netif_receive_skb(skb);
 696		rcv_pkts++;
 697		stats->rx_packets++;
 698		quota--;
 699		stats->rx_bytes += cf->len;
 700
 701		pch_fifo_thresh(priv, obj_num);
 702		obj_num++;
 703	} while (quota > 0);
 704
 705	return rcv_pkts;
 706}
 707
 708static void pch_can_tx_complete(struct net_device *ndev, u32 int_stat)
 709{
 710	struct pch_can_priv *priv = netdev_priv(ndev);
 711	struct net_device_stats *stats = &(priv->ndev->stats);
 712	u32 dlc;
 713
 714	can_get_echo_skb(ndev, int_stat - PCH_RX_OBJ_END - 1, NULL);
 715	iowrite32(PCH_CMASK_RX_TX_GET | PCH_CMASK_CLRINTPND,
 716		  &priv->regs->ifregs[1].cmask);
 717	pch_can_rw_msg_obj(&priv->regs->ifregs[1].creq, int_stat);
 718	dlc = can_cc_dlc2len(ioread32(&priv->regs->ifregs[1].mcont) &
 719			  PCH_IF_MCONT_DLC);
 720	stats->tx_bytes += dlc;
 721	stats->tx_packets++;
 722	if (int_stat == PCH_TX_OBJ_END)
 723		netif_wake_queue(ndev);
 724}
 725
 726static int pch_can_poll(struct napi_struct *napi, int quota)
 727{
 728	struct net_device *ndev = napi->dev;
 729	struct pch_can_priv *priv = netdev_priv(ndev);
 730	u32 int_stat;
 731	u32 reg_stat;
 732	int quota_save = quota;
 733
 734	int_stat = pch_can_int_pending(priv);
 735	if (!int_stat)
 736		goto end;
 737
 738	if (int_stat == PCH_STATUS_INT) {
 739		reg_stat = ioread32(&priv->regs->stat);
 740
 741		if ((reg_stat & (PCH_BUS_OFF | PCH_LEC_ALL)) &&
 742		   ((reg_stat & PCH_LEC_ALL) != PCH_LEC_ALL)) {
 743			pch_can_error(ndev, reg_stat);
 744			quota--;
 745		}
 746
 747		if (reg_stat & (PCH_TX_OK | PCH_RX_OK))
 748			pch_can_bit_clear(&priv->regs->stat,
 749					  reg_stat & (PCH_TX_OK | PCH_RX_OK));
 750
 751		int_stat = pch_can_int_pending(priv);
 752	}
 753
 754	if (quota == 0)
 755		goto end;
 756
 757	if ((int_stat >= PCH_RX_OBJ_START) && (int_stat <= PCH_RX_OBJ_END)) {
 758		quota -= pch_can_rx_normal(ndev, int_stat, quota);
 759	} else if ((int_stat >= PCH_TX_OBJ_START) &&
 760		   (int_stat <= PCH_TX_OBJ_END)) {
 761		/* Handle transmission interrupt */
 762		pch_can_tx_complete(ndev, int_stat);
 763	}
 764
 765end:
 766	napi_complete(napi);
 767	pch_can_set_int_enables(priv, PCH_CAN_ALL);
 768
 769	return quota_save - quota;
 770}
 771
 772static int pch_set_bittiming(struct net_device *ndev)
 773{
 774	struct pch_can_priv *priv = netdev_priv(ndev);
 775	const struct can_bittiming *bt = &priv->can.bittiming;
 776	u32 canbit;
 777	u32 bepe;
 778
 779	/* Setting the CCE bit for accessing the Can Timing register. */
 780	pch_can_bit_set(&priv->regs->cont, PCH_CTRL_CCE);
 781
 782	canbit = (bt->brp - 1) & PCH_MSK_BITT_BRP;
 783	canbit |= (bt->sjw - 1) << PCH_BIT_SJW_SHIFT;
 784	canbit |= (bt->phase_seg1 + bt->prop_seg - 1) << PCH_BIT_TSEG1_SHIFT;
 785	canbit |= (bt->phase_seg2 - 1) << PCH_BIT_TSEG2_SHIFT;
 786	bepe = ((bt->brp - 1) & PCH_MSK_BRPE_BRPE) >> PCH_BIT_BRPE_BRPE_SHIFT;
 787	iowrite32(canbit, &priv->regs->bitt);
 788	iowrite32(bepe, &priv->regs->brpe);
 789	pch_can_bit_clear(&priv->regs->cont, PCH_CTRL_CCE);
 790
 791	return 0;
 792}
 793
 794static void pch_can_start(struct net_device *ndev)
 795{
 796	struct pch_can_priv *priv = netdev_priv(ndev);
 797
 798	if (priv->can.state != CAN_STATE_STOPPED)
 799		pch_can_reset(priv);
 800
 801	pch_set_bittiming(ndev);
 802	pch_can_set_optmode(priv);
 803
 804	pch_can_set_tx_all(priv, 1);
 805	pch_can_set_rx_all(priv, 1);
 806
 807	/* Setting the CAN to run mode. */
 808	pch_can_set_run_mode(priv, PCH_CAN_RUN);
 809
 810	priv->can.state = CAN_STATE_ERROR_ACTIVE;
 811
 812	return;
 813}
 814
 815static int pch_can_do_set_mode(struct net_device *ndev, enum can_mode mode)
 816{
 817	int ret = 0;
 818
 819	switch (mode) {
 820	case CAN_MODE_START:
 821		pch_can_start(ndev);
 822		netif_wake_queue(ndev);
 823		break;
 824	default:
 825		ret = -EOPNOTSUPP;
 826		break;
 827	}
 828
 829	return ret;
 830}
 831
 832static int pch_can_open(struct net_device *ndev)
 833{
 834	struct pch_can_priv *priv = netdev_priv(ndev);
 835	int retval;
 836
 837	/* Registering the interrupt. */
 838	retval = request_irq(priv->dev->irq, pch_can_interrupt, IRQF_SHARED,
 839			     ndev->name, ndev);
 840	if (retval) {
 841		netdev_err(ndev, "request_irq failed.\n");
 842		goto req_irq_err;
 843	}
 844
 845	/* Open common can device */
 846	retval = open_candev(ndev);
 847	if (retval) {
 848		netdev_err(ndev, "open_candev() failed %d\n", retval);
 849		goto err_open_candev;
 850	}
 851
 852	pch_can_init(priv);
 853	pch_can_start(ndev);
 854	napi_enable(&priv->napi);
 855	netif_start_queue(ndev);
 856
 857	return 0;
 858
 859err_open_candev:
 860	free_irq(priv->dev->irq, ndev);
 861req_irq_err:
 862	pch_can_release(priv);
 863
 864	return retval;
 865}
 866
 867static int pch_close(struct net_device *ndev)
 868{
 869	struct pch_can_priv *priv = netdev_priv(ndev);
 870
 871	netif_stop_queue(ndev);
 872	napi_disable(&priv->napi);
 873	pch_can_release(priv);
 874	free_irq(priv->dev->irq, ndev);
 875	close_candev(ndev);
 876	priv->can.state = CAN_STATE_STOPPED;
 877	return 0;
 878}
 879
 880static netdev_tx_t pch_xmit(struct sk_buff *skb, struct net_device *ndev)
 881{
 882	struct pch_can_priv *priv = netdev_priv(ndev);
 883	struct can_frame *cf = (struct can_frame *)skb->data;
 884	int tx_obj_no;
 885	int i;
 886	u32 id2;
 887
 888	if (can_dropped_invalid_skb(ndev, skb))
 889		return NETDEV_TX_OK;
 890
 891	tx_obj_no = priv->tx_obj;
 892	if (priv->tx_obj == PCH_TX_OBJ_END) {
 893		if (ioread32(&priv->regs->treq2) & PCH_TREQ2_TX_MASK)
 894			netif_stop_queue(ndev);
 895
 896		priv->tx_obj = PCH_TX_OBJ_START;
 897	} else {
 898		priv->tx_obj++;
 899	}
 900
 901	/* Setting the CMASK register. */
 902	pch_can_bit_set(&priv->regs->ifregs[1].cmask, PCH_CMASK_ALL);
 903
 904	/* If ID extended is set. */
 905	if (cf->can_id & CAN_EFF_FLAG) {
 906		iowrite32(cf->can_id & 0xffff, &priv->regs->ifregs[1].id1);
 907		id2 = ((cf->can_id >> 16) & 0x1fff) | PCH_ID2_XTD;
 908	} else {
 909		iowrite32(0, &priv->regs->ifregs[1].id1);
 910		id2 = (cf->can_id & CAN_SFF_MASK) << 2;
 911	}
 912
 913	id2 |= PCH_ID_MSGVAL;
 914
 915	/* If remote frame has to be transmitted.. */
 916	if (!(cf->can_id & CAN_RTR_FLAG))
 917		id2 |= PCH_ID2_DIR;
 918
 919	iowrite32(id2, &priv->regs->ifregs[1].id2);
 920
 921	/* Copy data to register */
 922	for (i = 0; i < cf->len; i += 2) {
 923		iowrite16(cf->data[i] | (cf->data[i + 1] << 8),
 924			  &priv->regs->ifregs[1].data[i / 2]);
 925	}
 926
 927	can_put_echo_skb(skb, ndev, tx_obj_no - PCH_RX_OBJ_END - 1, 0);
 928
 929	/* Set the size of the data. Update if2_mcont */
 930	iowrite32(cf->len | PCH_IF_MCONT_NEWDAT | PCH_IF_MCONT_TXRQXT |
 931		  PCH_IF_MCONT_TXIE, &priv->regs->ifregs[1].mcont);
 932
 933	pch_can_rw_msg_obj(&priv->regs->ifregs[1].creq, tx_obj_no);
 934
 935	return NETDEV_TX_OK;
 936}
 937
 938static const struct net_device_ops pch_can_netdev_ops = {
 939	.ndo_open		= pch_can_open,
 940	.ndo_stop		= pch_close,
 941	.ndo_start_xmit		= pch_xmit,
 942	.ndo_change_mtu		= can_change_mtu,
 943};
 944
 945static void pch_can_remove(struct pci_dev *pdev)
 946{
 947	struct net_device *ndev = pci_get_drvdata(pdev);
 948	struct pch_can_priv *priv = netdev_priv(ndev);
 949
 950	unregister_candev(priv->ndev);
 951	if (priv->use_msi)
 952		pci_disable_msi(priv->dev);
 953	pci_release_regions(pdev);
 954	pci_disable_device(pdev);
 955	pch_can_reset(priv);
 956	pci_iounmap(pdev, priv->regs);
 957	free_candev(priv->ndev);
 958}
 959
 960static void __maybe_unused pch_can_set_int_custom(struct pch_can_priv *priv)
 961{
 962	/* Clearing the IE, SIE and EIE bits of Can control register. */
 963	pch_can_bit_clear(&priv->regs->cont, PCH_CTRL_IE_SIE_EIE);
 964
 965	/* Appropriately setting them. */
 966	pch_can_bit_set(&priv->regs->cont,
 967			((priv->int_enables & PCH_MSK_CTRL_IE_SIE_EIE) << 1));
 968}
 969
 970/* This function retrieves interrupt enabled for the CAN device. */
 971static u32 __maybe_unused pch_can_get_int_enables(struct pch_can_priv *priv)
 972{
 973	/* Obtaining the status of IE, SIE and EIE interrupt bits. */
 974	return (ioread32(&priv->regs->cont) & PCH_CTRL_IE_SIE_EIE) >> 1;
 975}
 976
 977static u32 __maybe_unused pch_can_get_rxtx_ir(struct pch_can_priv *priv,
 978					      u32 buff_num, enum pch_ifreg dir)
 979{
 980	u32 ie, enable;
 981
 982	if (dir)
 983		ie = PCH_IF_MCONT_RXIE;
 984	else
 985		ie = PCH_IF_MCONT_TXIE;
 986
 987	iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[dir].cmask);
 988	pch_can_rw_msg_obj(&priv->regs->ifregs[dir].creq, buff_num);
 989
 990	if (((ioread32(&priv->regs->ifregs[dir].id2)) & PCH_ID_MSGVAL) &&
 991			((ioread32(&priv->regs->ifregs[dir].mcont)) & ie))
 992		enable = 1;
 993	else
 994		enable = 0;
 995
 996	return enable;
 997}
 998
 999static void __maybe_unused pch_can_set_rx_buffer_link(struct pch_can_priv *priv,
1000						      u32 buffer_num, int set)
1001{
1002	iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[0].cmask);
1003	pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, buffer_num);
1004	iowrite32(PCH_CMASK_RDWR | PCH_CMASK_CTRL,
1005		  &priv->regs->ifregs[0].cmask);
1006	if (set)
1007		pch_can_bit_clear(&priv->regs->ifregs[0].mcont,
1008				  PCH_IF_MCONT_EOB);
1009	else
1010		pch_can_bit_set(&priv->regs->ifregs[0].mcont, PCH_IF_MCONT_EOB);
1011
1012	pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, buffer_num);
1013}
1014
1015static u32 __maybe_unused pch_can_get_rx_buffer_link(struct pch_can_priv *priv,
1016						     u32 buffer_num)
1017{
1018	u32 link;
1019
1020	iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[0].cmask);
1021	pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, buffer_num);
1022
1023	if (ioread32(&priv->regs->ifregs[0].mcont) & PCH_IF_MCONT_EOB)
1024		link = 0;
1025	else
1026		link = 1;
1027	return link;
1028}
1029
1030static int __maybe_unused pch_can_get_buffer_status(struct pch_can_priv *priv)
1031{
1032	return (ioread32(&priv->regs->treq1) & 0xffff) |
1033	       (ioread32(&priv->regs->treq2) << 16);
1034}
1035
1036static int __maybe_unused pch_can_suspend(struct device *dev_d)
1037{
1038	int i;
1039	u32 buf_stat;	/* Variable for reading the transmit buffer status. */
1040	int counter = PCH_COUNTER_LIMIT;
1041
1042	struct net_device *dev = dev_get_drvdata(dev_d);
1043	struct pch_can_priv *priv = netdev_priv(dev);
1044
1045	/* Stop the CAN controller */
1046	pch_can_set_run_mode(priv, PCH_CAN_STOP);
1047
1048	/* Indicate that we are aboutto/in suspend */
1049	priv->can.state = CAN_STATE_STOPPED;
1050
1051	/* Waiting for all transmission to complete. */
1052	while (counter) {
1053		buf_stat = pch_can_get_buffer_status(priv);
1054		if (!buf_stat)
1055			break;
1056		counter--;
1057		udelay(1);
1058	}
1059	if (!counter)
1060		dev_err(dev_d, "%s -> Transmission time out.\n", __func__);
1061
1062	/* Save interrupt configuration and then disable them */
1063	priv->int_enables = pch_can_get_int_enables(priv);
1064	pch_can_set_int_enables(priv, PCH_CAN_DISABLE);
1065
1066	/* Save Tx buffer enable state */
1067	for (i = PCH_TX_OBJ_START; i <= PCH_TX_OBJ_END; i++)
1068		priv->tx_enable[i - 1] = pch_can_get_rxtx_ir(priv, i,
1069							     PCH_TX_IFREG);
1070
1071	/* Disable all Transmit buffers */
1072	pch_can_set_tx_all(priv, 0);
1073
1074	/* Save Rx buffer enable state */
1075	for (i = PCH_RX_OBJ_START; i <= PCH_RX_OBJ_END; i++) {
1076		priv->rx_enable[i - 1] = pch_can_get_rxtx_ir(priv, i,
1077							     PCH_RX_IFREG);
1078		priv->rx_link[i - 1] = pch_can_get_rx_buffer_link(priv, i);
1079	}
1080
1081	/* Disable all Receive buffers */
1082	pch_can_set_rx_all(priv, 0);
1083
1084	return 0;
1085}
1086
1087static int __maybe_unused pch_can_resume(struct device *dev_d)
1088{
1089	int i;
1090	struct net_device *dev = dev_get_drvdata(dev_d);
1091	struct pch_can_priv *priv = netdev_priv(dev);
1092
1093	priv->can.state = CAN_STATE_ERROR_ACTIVE;
1094
1095	/* Disabling all interrupts. */
1096	pch_can_set_int_enables(priv, PCH_CAN_DISABLE);
1097
1098	/* Setting the CAN device in Stop Mode. */
1099	pch_can_set_run_mode(priv, PCH_CAN_STOP);
1100
1101	/* Configuring the transmit and receive buffers. */
1102	pch_can_config_rx_tx_buffers(priv);
1103
1104	/* Restore the CAN state */
1105	pch_set_bittiming(dev);
1106
1107	/* Listen/Active */
1108	pch_can_set_optmode(priv);
1109
1110	/* Enabling the transmit buffer. */
1111	for (i = PCH_TX_OBJ_START; i <= PCH_TX_OBJ_END; i++)
1112		pch_can_set_rxtx(priv, i, priv->tx_enable[i - 1], PCH_TX_IFREG);
1113
1114	/* Configuring the receive buffer and enabling them. */
1115	for (i = PCH_RX_OBJ_START; i <= PCH_RX_OBJ_END; i++) {
1116		/* Restore buffer link */
1117		pch_can_set_rx_buffer_link(priv, i, priv->rx_link[i - 1]);
1118
1119		/* Restore buffer enables */
1120		pch_can_set_rxtx(priv, i, priv->rx_enable[i - 1], PCH_RX_IFREG);
1121	}
1122
1123	/* Enable CAN Interrupts */
1124	pch_can_set_int_custom(priv);
1125
1126	/* Restore Run Mode */
1127	pch_can_set_run_mode(priv, PCH_CAN_RUN);
1128
1129	return 0;
1130}
1131
1132static int pch_can_get_berr_counter(const struct net_device *dev,
1133				    struct can_berr_counter *bec)
1134{
1135	struct pch_can_priv *priv = netdev_priv(dev);
1136	u32 errc = ioread32(&priv->regs->errc);
1137
1138	bec->txerr = errc & PCH_TEC;
1139	bec->rxerr = (errc & PCH_REC) >> 8;
1140
1141	return 0;
1142}
1143
1144static int pch_can_probe(struct pci_dev *pdev,
1145				   const struct pci_device_id *id)
1146{
1147	struct net_device *ndev;
1148	struct pch_can_priv *priv;
1149	int rc;
1150	void __iomem *addr;
1151
1152	rc = pci_enable_device(pdev);
1153	if (rc) {
1154		dev_err(&pdev->dev, "Failed pci_enable_device %d\n", rc);
1155		goto probe_exit_endev;
1156	}
1157
1158	rc = pci_request_regions(pdev, KBUILD_MODNAME);
1159	if (rc) {
1160		dev_err(&pdev->dev, "Failed pci_request_regions %d\n", rc);
1161		goto probe_exit_pcireq;
1162	}
1163
1164	addr = pci_iomap(pdev, 1, 0);
1165	if (!addr) {
1166		rc = -EIO;
1167		dev_err(&pdev->dev, "Failed pci_iomap\n");
1168		goto probe_exit_ipmap;
1169	}
1170
1171	ndev = alloc_candev(sizeof(struct pch_can_priv), PCH_TX_OBJ_END);
1172	if (!ndev) {
1173		rc = -ENOMEM;
1174		dev_err(&pdev->dev, "Failed alloc_candev\n");
1175		goto probe_exit_alloc_candev;
1176	}
1177
1178	priv = netdev_priv(ndev);
1179	priv->ndev = ndev;
1180	priv->regs = addr;
1181	priv->dev = pdev;
1182	priv->can.bittiming_const = &pch_can_bittiming_const;
1183	priv->can.do_set_mode = pch_can_do_set_mode;
1184	priv->can.do_get_berr_counter = pch_can_get_berr_counter;
1185	priv->can.ctrlmode_supported = CAN_CTRLMODE_LISTENONLY |
1186				       CAN_CTRLMODE_LOOPBACK;
1187	priv->tx_obj = PCH_TX_OBJ_START; /* Point head of Tx Obj */
1188
1189	ndev->irq = pdev->irq;
1190	ndev->flags |= IFF_ECHO;
1191
1192	pci_set_drvdata(pdev, ndev);
1193	SET_NETDEV_DEV(ndev, &pdev->dev);
1194	ndev->netdev_ops = &pch_can_netdev_ops;
1195	priv->can.clock.freq = PCH_CAN_CLK; /* Hz */
1196
1197	netif_napi_add(ndev, &priv->napi, pch_can_poll, PCH_RX_OBJ_END);
1198
1199	rc = pci_enable_msi(priv->dev);
1200	if (rc) {
1201		netdev_err(ndev, "PCH CAN opened without MSI\n");
1202		priv->use_msi = 0;
1203	} else {
1204		netdev_err(ndev, "PCH CAN opened with MSI\n");
1205		pci_set_master(pdev);
1206		priv->use_msi = 1;
1207	}
1208
1209	rc = register_candev(ndev);
1210	if (rc) {
1211		dev_err(&pdev->dev, "Failed register_candev %d\n", rc);
1212		goto probe_exit_reg_candev;
1213	}
1214
1215	return 0;
1216
1217probe_exit_reg_candev:
1218	if (priv->use_msi)
1219		pci_disable_msi(priv->dev);
1220	free_candev(ndev);
1221probe_exit_alloc_candev:
1222	pci_iounmap(pdev, addr);
1223probe_exit_ipmap:
1224	pci_release_regions(pdev);
1225probe_exit_pcireq:
1226	pci_disable_device(pdev);
1227probe_exit_endev:
1228	return rc;
1229}
1230
1231static SIMPLE_DEV_PM_OPS(pch_can_pm_ops,
1232			 pch_can_suspend,
1233			 pch_can_resume);
1234
1235static struct pci_driver pch_can_pci_driver = {
1236	.name = "pch_can",
1237	.id_table = pch_pci_tbl,
1238	.probe = pch_can_probe,
1239	.remove = pch_can_remove,
1240	.driver.pm = &pch_can_pm_ops,
1241};
1242
1243module_pci_driver(pch_can_pci_driver);
1244
1245MODULE_DESCRIPTION("Intel EG20T PCH CAN(Controller Area Network) Driver");
1246MODULE_LICENSE("GPL v2");
1247MODULE_VERSION("0.94");
   1/*
   2 * Copyright (C) 1999 - 2010 Intel Corporation.
   3 * Copyright (C) 2010 OKI SEMICONDUCTOR CO., LTD.
   4 *
   5 * This program is free software; you can redistribute it and/or modify
   6 * it under the terms of the GNU General Public License as published by
   7 * the Free Software Foundation; version 2 of the License.
   8 *
   9 * This program is distributed in the hope that it will be useful,
  10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 * GNU General Public License for more details.
  13 *
  14 * You should have received a copy of the GNU General Public License
  15 * along with this program; if not, write to the Free Software
  16 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
  17 */
  18
  19#include <linux/interrupt.h>
  20#include <linux/delay.h>
  21#include <linux/io.h>
  22#include <linux/module.h>
  23#include <linux/sched.h>
  24#include <linux/pci.h>
  25#include <linux/init.h>
  26#include <linux/kernel.h>
  27#include <linux/types.h>
  28#include <linux/errno.h>
  29#include <linux/netdevice.h>
  30#include <linux/skbuff.h>
  31#include <linux/can.h>
  32#include <linux/can/dev.h>
  33#include <linux/can/error.h>
  34
  35#define PCH_CTRL_INIT		BIT(0) /* The INIT bit of CANCONT register. */
  36#define PCH_CTRL_IE		BIT(1) /* The IE bit of CAN control register */
  37#define PCH_CTRL_IE_SIE_EIE	(BIT(3) | BIT(2) | BIT(1))
  38#define PCH_CTRL_CCE		BIT(6)
  39#define PCH_CTRL_OPT		BIT(7) /* The OPT bit of CANCONT register. */
  40#define PCH_OPT_SILENT		BIT(3) /* The Silent bit of CANOPT reg. */
  41#define PCH_OPT_LBACK		BIT(4) /* The LoopBack bit of CANOPT reg. */
  42
  43#define PCH_CMASK_RX_TX_SET	0x00f3
  44#define PCH_CMASK_RX_TX_GET	0x0073
  45#define PCH_CMASK_ALL		0xff
  46#define PCH_CMASK_NEWDAT	BIT(2)
  47#define PCH_CMASK_CLRINTPND	BIT(3)
  48#define PCH_CMASK_CTRL		BIT(4)
  49#define PCH_CMASK_ARB		BIT(5)
  50#define PCH_CMASK_MASK		BIT(6)
  51#define PCH_CMASK_RDWR		BIT(7)
  52#define PCH_IF_MCONT_NEWDAT	BIT(15)
  53#define PCH_IF_MCONT_MSGLOST	BIT(14)
  54#define PCH_IF_MCONT_INTPND	BIT(13)
  55#define PCH_IF_MCONT_UMASK	BIT(12)
  56#define PCH_IF_MCONT_TXIE	BIT(11)
  57#define PCH_IF_MCONT_RXIE	BIT(10)
  58#define PCH_IF_MCONT_RMTEN	BIT(9)
  59#define PCH_IF_MCONT_TXRQXT	BIT(8)
  60#define PCH_IF_MCONT_EOB	BIT(7)
  61#define PCH_IF_MCONT_DLC	(BIT(0) | BIT(1) | BIT(2) | BIT(3))
  62#define PCH_MASK2_MDIR_MXTD	(BIT(14) | BIT(15))
  63#define PCH_ID2_DIR		BIT(13)
  64#define PCH_ID2_XTD		BIT(14)
  65#define PCH_ID_MSGVAL		BIT(15)
  66#define PCH_IF_CREQ_BUSY	BIT(15)
  67
  68#define PCH_STATUS_INT		0x8000
  69#define PCH_REC			0x00007f00
  70#define PCH_TEC			0x000000ff
  71
  72#define PCH_TX_OK		BIT(3)
  73#define PCH_RX_OK		BIT(4)
  74#define PCH_EPASSIV		BIT(5)
  75#define PCH_EWARN		BIT(6)
  76#define PCH_BUS_OFF		BIT(7)
  77
  78/* bit position of certain controller bits. */
  79#define PCH_BIT_BRP_SHIFT	0
  80#define PCH_BIT_SJW_SHIFT	6
  81#define PCH_BIT_TSEG1_SHIFT	8
  82#define PCH_BIT_TSEG2_SHIFT	12
  83#define PCH_BIT_BRPE_BRPE_SHIFT	6
  84
  85#define PCH_MSK_BITT_BRP	0x3f
  86#define PCH_MSK_BRPE_BRPE	0x3c0
  87#define PCH_MSK_CTRL_IE_SIE_EIE	0x07
  88#define PCH_COUNTER_LIMIT	10
  89
  90#define PCH_CAN_CLK		50000000	/* 50MHz */
  91
  92/*
  93 * Define the number of message object.
  94 * PCH CAN communications are done via Message RAM.
  95 * The Message RAM consists of 32 message objects.
  96 */
  97#define PCH_RX_OBJ_NUM		26
  98#define PCH_TX_OBJ_NUM		6
  99#define PCH_RX_OBJ_START	1
 100#define PCH_RX_OBJ_END		PCH_RX_OBJ_NUM
 101#define PCH_TX_OBJ_START	(PCH_RX_OBJ_END + 1)
 102#define PCH_TX_OBJ_END		(PCH_RX_OBJ_NUM + PCH_TX_OBJ_NUM)
 103
 104#define PCH_FIFO_THRESH		16
 105
 106/* TxRqst2 show status of MsgObjNo.17~32 */
 107#define PCH_TREQ2_TX_MASK	(((1 << PCH_TX_OBJ_NUM) - 1) <<\
 108							(PCH_RX_OBJ_END - 16))
 109
 110enum pch_ifreg {
 111	PCH_RX_IFREG,
 112	PCH_TX_IFREG,
 113};
 114
 115enum pch_can_err {
 116	PCH_STUF_ERR = 1,
 117	PCH_FORM_ERR,
 118	PCH_ACK_ERR,
 119	PCH_BIT1_ERR,
 120	PCH_BIT0_ERR,
 121	PCH_CRC_ERR,
 122	PCH_LEC_ALL,
 123};
 124
 125enum pch_can_mode {
 126	PCH_CAN_ENABLE,
 127	PCH_CAN_DISABLE,
 128	PCH_CAN_ALL,
 129	PCH_CAN_NONE,
 130	PCH_CAN_STOP,
 131	PCH_CAN_RUN,
 132};
 133
 134struct pch_can_if_regs {
 135	u32 creq;
 136	u32 cmask;
 137	u32 mask1;
 138	u32 mask2;
 139	u32 id1;
 140	u32 id2;
 141	u32 mcont;
 142	u32 data[4];
 143	u32 rsv[13];
 144};
 145
 146struct pch_can_regs {
 147	u32 cont;
 148	u32 stat;
 149	u32 errc;
 150	u32 bitt;
 151	u32 intr;
 152	u32 opt;
 153	u32 brpe;
 154	u32 reserve;
 155	struct pch_can_if_regs ifregs[2]; /* [0]=if1  [1]=if2 */
 156	u32 reserve1[8];
 157	u32 treq1;
 158	u32 treq2;
 159	u32 reserve2[6];
 160	u32 data1;
 161	u32 data2;
 162	u32 reserve3[6];
 163	u32 canipend1;
 164	u32 canipend2;
 165	u32 reserve4[6];
 166	u32 canmval1;
 167	u32 canmval2;
 168	u32 reserve5[37];
 169	u32 srst;
 170};
 171
 172struct pch_can_priv {
 173	struct can_priv can;
 174	struct pci_dev *dev;
 175	u32 tx_enable[PCH_TX_OBJ_END];
 176	u32 rx_enable[PCH_TX_OBJ_END];
 177	u32 rx_link[PCH_TX_OBJ_END];
 178	u32 int_enables;
 179	struct net_device *ndev;
 180	struct pch_can_regs __iomem *regs;
 181	struct napi_struct napi;
 182	int tx_obj;	/* Point next Tx Obj index */
 183	int use_msi;
 184};
 185
 186static struct can_bittiming_const pch_can_bittiming_const = {
 187	.name = KBUILD_MODNAME,
 188	.tseg1_min = 2,
 189	.tseg1_max = 16,
 190	.tseg2_min = 1,
 191	.tseg2_max = 8,
 192	.sjw_max = 4,
 193	.brp_min = 1,
 194	.brp_max = 1024, /* 6bit + extended 4bit */
 195	.brp_inc = 1,
 196};
 197
 198static DEFINE_PCI_DEVICE_TABLE(pch_pci_tbl) = {
 199	{PCI_VENDOR_ID_INTEL, 0x8818, PCI_ANY_ID, PCI_ANY_ID,},
 200	{0,}
 201};
 202MODULE_DEVICE_TABLE(pci, pch_pci_tbl);
 203
 204static inline void pch_can_bit_set(void __iomem *addr, u32 mask)
 205{
 206	iowrite32(ioread32(addr) | mask, addr);
 207}
 208
 209static inline void pch_can_bit_clear(void __iomem *addr, u32 mask)
 210{
 211	iowrite32(ioread32(addr) & ~mask, addr);
 212}
 213
 214static void pch_can_set_run_mode(struct pch_can_priv *priv,
 215				 enum pch_can_mode mode)
 216{
 217	switch (mode) {
 218	case PCH_CAN_RUN:
 219		pch_can_bit_clear(&priv->regs->cont, PCH_CTRL_INIT);
 220		break;
 221
 222	case PCH_CAN_STOP:
 223		pch_can_bit_set(&priv->regs->cont, PCH_CTRL_INIT);
 224		break;
 225
 226	default:
 227		netdev_err(priv->ndev, "%s -> Invalid Mode.\n", __func__);
 228		break;
 229	}
 230}
 231
 232static void pch_can_set_optmode(struct pch_can_priv *priv)
 233{
 234	u32 reg_val = ioread32(&priv->regs->opt);
 235
 236	if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
 237		reg_val |= PCH_OPT_SILENT;
 238
 239	if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
 240		reg_val |= PCH_OPT_LBACK;
 241
 242	pch_can_bit_set(&priv->regs->cont, PCH_CTRL_OPT);
 243	iowrite32(reg_val, &priv->regs->opt);
 244}
 245
 246static void pch_can_rw_msg_obj(void __iomem *creq_addr, u32 num)
 247{
 248	int counter = PCH_COUNTER_LIMIT;
 249	u32 ifx_creq;
 250
 251	iowrite32(num, creq_addr);
 252	while (counter) {
 253		ifx_creq = ioread32(creq_addr) & PCH_IF_CREQ_BUSY;
 254		if (!ifx_creq)
 255			break;
 256		counter--;
 257		udelay(1);
 258	}
 259	if (!counter)
 260		pr_err("%s:IF1 BUSY Flag is set forever.\n", __func__);
 261}
 262
 263static void pch_can_set_int_enables(struct pch_can_priv *priv,
 264				    enum pch_can_mode interrupt_no)
 265{
 266	switch (interrupt_no) {
 267	case PCH_CAN_DISABLE:
 268		pch_can_bit_clear(&priv->regs->cont, PCH_CTRL_IE);
 269		break;
 270
 271	case PCH_CAN_ALL:
 272		pch_can_bit_set(&priv->regs->cont, PCH_CTRL_IE_SIE_EIE);
 273		break;
 274
 275	case PCH_CAN_NONE:
 276		pch_can_bit_clear(&priv->regs->cont, PCH_CTRL_IE_SIE_EIE);
 277		break;
 278
 279	default:
 280		netdev_err(priv->ndev, "Invalid interrupt number.\n");
 281		break;
 282	}
 283}
 284
 285static void pch_can_set_rxtx(struct pch_can_priv *priv, u32 buff_num,
 286			     int set, enum pch_ifreg dir)
 287{
 288	u32 ie;
 289
 290	if (dir)
 291		ie = PCH_IF_MCONT_TXIE;
 292	else
 293		ie = PCH_IF_MCONT_RXIE;
 294
 295	/* Reading the Msg buffer from Message RAM to IF1/2 registers. */
 296	iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[dir].cmask);
 297	pch_can_rw_msg_obj(&priv->regs->ifregs[dir].creq, buff_num);
 298
 299	/* Setting the IF1/2MASK1 register to access MsgVal and RxIE bits */
 300	iowrite32(PCH_CMASK_RDWR | PCH_CMASK_ARB | PCH_CMASK_CTRL,
 301		  &priv->regs->ifregs[dir].cmask);
 302
 303	if (set) {
 304		/* Setting the MsgVal and RxIE/TxIE bits */
 305		pch_can_bit_set(&priv->regs->ifregs[dir].mcont, ie);
 306		pch_can_bit_set(&priv->regs->ifregs[dir].id2, PCH_ID_MSGVAL);
 307	} else {
 308		/* Clearing the MsgVal and RxIE/TxIE bits */
 309		pch_can_bit_clear(&priv->regs->ifregs[dir].mcont, ie);
 310		pch_can_bit_clear(&priv->regs->ifregs[dir].id2, PCH_ID_MSGVAL);
 311	}
 312
 313	pch_can_rw_msg_obj(&priv->regs->ifregs[dir].creq, buff_num);
 314}
 315
 316static void pch_can_set_rx_all(struct pch_can_priv *priv, int set)
 317{
 318	int i;
 319
 320	/* Traversing to obtain the object configured as receivers. */
 321	for (i = PCH_RX_OBJ_START; i <= PCH_RX_OBJ_END; i++)
 322		pch_can_set_rxtx(priv, i, set, PCH_RX_IFREG);
 323}
 324
 325static void pch_can_set_tx_all(struct pch_can_priv *priv, int set)
 326{
 327	int i;
 328
 329	/* Traversing to obtain the object configured as transmit object. */
 330	for (i = PCH_TX_OBJ_START; i <= PCH_TX_OBJ_END; i++)
 331		pch_can_set_rxtx(priv, i, set, PCH_TX_IFREG);
 332}
 333
 334static u32 pch_can_int_pending(struct pch_can_priv *priv)
 335{
 336	return ioread32(&priv->regs->intr) & 0xffff;
 337}
 338
 339static void pch_can_clear_if_buffers(struct pch_can_priv *priv)
 340{
 341	int i; /* Msg Obj ID (1~32) */
 342
 343	for (i = PCH_RX_OBJ_START; i <= PCH_TX_OBJ_END; i++) {
 344		iowrite32(PCH_CMASK_RX_TX_SET, &priv->regs->ifregs[0].cmask);
 345		iowrite32(0xffff, &priv->regs->ifregs[0].mask1);
 346		iowrite32(0xffff, &priv->regs->ifregs[0].mask2);
 347		iowrite32(0x0, &priv->regs->ifregs[0].id1);
 348		iowrite32(0x0, &priv->regs->ifregs[0].id2);
 349		iowrite32(0x0, &priv->regs->ifregs[0].mcont);
 350		iowrite32(0x0, &priv->regs->ifregs[0].data[0]);
 351		iowrite32(0x0, &priv->regs->ifregs[0].data[1]);
 352		iowrite32(0x0, &priv->regs->ifregs[0].data[2]);
 353		iowrite32(0x0, &priv->regs->ifregs[0].data[3]);
 354		iowrite32(PCH_CMASK_RDWR | PCH_CMASK_MASK |
 355			  PCH_CMASK_ARB | PCH_CMASK_CTRL,
 356			  &priv->regs->ifregs[0].cmask);
 357		pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, i);
 358	}
 359}
 360
 361static void pch_can_config_rx_tx_buffers(struct pch_can_priv *priv)
 362{
 363	int i;
 364
 365	for (i = PCH_RX_OBJ_START; i <= PCH_RX_OBJ_END; i++) {
 366		iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[0].cmask);
 367		pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, i);
 368
 369		iowrite32(0x0, &priv->regs->ifregs[0].id1);
 370		iowrite32(0x0, &priv->regs->ifregs[0].id2);
 371
 372		pch_can_bit_set(&priv->regs->ifregs[0].mcont,
 373				PCH_IF_MCONT_UMASK);
 374
 375		/* In case FIFO mode, Last EoB of Rx Obj must be 1 */
 376		if (i == PCH_RX_OBJ_END)
 377			pch_can_bit_set(&priv->regs->ifregs[0].mcont,
 378					PCH_IF_MCONT_EOB);
 379		else
 380			pch_can_bit_clear(&priv->regs->ifregs[0].mcont,
 381					  PCH_IF_MCONT_EOB);
 382
 383		iowrite32(0, &priv->regs->ifregs[0].mask1);
 384		pch_can_bit_clear(&priv->regs->ifregs[0].mask2,
 385				  0x1fff | PCH_MASK2_MDIR_MXTD);
 386
 387		/* Setting CMASK for writing */
 388		iowrite32(PCH_CMASK_RDWR | PCH_CMASK_MASK | PCH_CMASK_ARB |
 389			  PCH_CMASK_CTRL, &priv->regs->ifregs[0].cmask);
 390
 391		pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, i);
 392	}
 393
 394	for (i = PCH_TX_OBJ_START; i <= PCH_TX_OBJ_END; i++) {
 395		iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[1].cmask);
 396		pch_can_rw_msg_obj(&priv->regs->ifregs[1].creq, i);
 397
 398		/* Resetting DIR bit for reception */
 399		iowrite32(0x0, &priv->regs->ifregs[1].id1);
 400		iowrite32(PCH_ID2_DIR, &priv->regs->ifregs[1].id2);
 401
 402		/* Setting EOB bit for transmitter */
 403		iowrite32(PCH_IF_MCONT_EOB | PCH_IF_MCONT_UMASK,
 404			  &priv->regs->ifregs[1].mcont);
 405
 406		iowrite32(0, &priv->regs->ifregs[1].mask1);
 407		pch_can_bit_clear(&priv->regs->ifregs[1].mask2, 0x1fff);
 408
 409		/* Setting CMASK for writing */
 410		iowrite32(PCH_CMASK_RDWR | PCH_CMASK_MASK | PCH_CMASK_ARB |
 411			  PCH_CMASK_CTRL, &priv->regs->ifregs[1].cmask);
 412
 413		pch_can_rw_msg_obj(&priv->regs->ifregs[1].creq, i);
 414	}
 415}
 416
 417static void pch_can_init(struct pch_can_priv *priv)
 418{
 419	/* Stopping the Can device. */
 420	pch_can_set_run_mode(priv, PCH_CAN_STOP);
 421
 422	/* Clearing all the message object buffers. */
 423	pch_can_clear_if_buffers(priv);
 424
 425	/* Configuring the respective message object as either rx/tx object. */
 426	pch_can_config_rx_tx_buffers(priv);
 427
 428	/* Enabling the interrupts. */
 429	pch_can_set_int_enables(priv, PCH_CAN_ALL);
 430}
 431
 432static void pch_can_release(struct pch_can_priv *priv)
 433{
 434	/* Stooping the CAN device. */
 435	pch_can_set_run_mode(priv, PCH_CAN_STOP);
 436
 437	/* Disabling the interrupts. */
 438	pch_can_set_int_enables(priv, PCH_CAN_NONE);
 439
 440	/* Disabling all the receive object. */
 441	pch_can_set_rx_all(priv, 0);
 442
 443	/* Disabling all the transmit object. */
 444	pch_can_set_tx_all(priv, 0);
 445}
 446
 447/* This function clears interrupt(s) from the CAN device. */
 448static void pch_can_int_clr(struct pch_can_priv *priv, u32 mask)
 449{
 450	/* Clear interrupt for transmit object */
 451	if ((mask >= PCH_RX_OBJ_START) && (mask <= PCH_RX_OBJ_END)) {
 452		/* Setting CMASK for clearing the reception interrupts. */
 453		iowrite32(PCH_CMASK_RDWR | PCH_CMASK_CTRL | PCH_CMASK_ARB,
 454			  &priv->regs->ifregs[0].cmask);
 455
 456		/* Clearing the Dir bit. */
 457		pch_can_bit_clear(&priv->regs->ifregs[0].id2, PCH_ID2_DIR);
 458
 459		/* Clearing NewDat & IntPnd */
 460		pch_can_bit_clear(&priv->regs->ifregs[0].mcont,
 461				  PCH_IF_MCONT_NEWDAT | PCH_IF_MCONT_INTPND);
 462
 463		pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, mask);
 464	} else if ((mask >= PCH_TX_OBJ_START) && (mask <= PCH_TX_OBJ_END)) {
 465		/*
 466		 * Setting CMASK for clearing interrupts for frame transmission.
 467		 */
 468		iowrite32(PCH_CMASK_RDWR | PCH_CMASK_CTRL | PCH_CMASK_ARB,
 469			  &priv->regs->ifregs[1].cmask);
 470
 471		/* Resetting the ID registers. */
 472		pch_can_bit_set(&priv->regs->ifregs[1].id2,
 473			       PCH_ID2_DIR | (0x7ff << 2));
 474		iowrite32(0x0, &priv->regs->ifregs[1].id1);
 475
 476		/* Claring NewDat, TxRqst & IntPnd */
 477		pch_can_bit_clear(&priv->regs->ifregs[1].mcont,
 478				  PCH_IF_MCONT_NEWDAT | PCH_IF_MCONT_INTPND |
 479				  PCH_IF_MCONT_TXRQXT);
 480		pch_can_rw_msg_obj(&priv->regs->ifregs[1].creq, mask);
 481	}
 482}
 483
 484static void pch_can_reset(struct pch_can_priv *priv)
 485{
 486	/* write to sw reset register */
 487	iowrite32(1, &priv->regs->srst);
 488	iowrite32(0, &priv->regs->srst);
 489}
 490
 491static void pch_can_error(struct net_device *ndev, u32 status)
 492{
 493	struct sk_buff *skb;
 494	struct pch_can_priv *priv = netdev_priv(ndev);
 495	struct can_frame *cf;
 496	u32 errc, lec;
 497	struct net_device_stats *stats = &(priv->ndev->stats);
 498	enum can_state state = priv->can.state;
 499
 500	skb = alloc_can_err_skb(ndev, &cf);
 501	if (!skb)
 502		return;
 503
 504	if (status & PCH_BUS_OFF) {
 505		pch_can_set_tx_all(priv, 0);
 506		pch_can_set_rx_all(priv, 0);
 507		state = CAN_STATE_BUS_OFF;
 508		cf->can_id |= CAN_ERR_BUSOFF;
 509		can_bus_off(ndev);
 510	}
 511
 512	errc = ioread32(&priv->regs->errc);
 513	/* Warning interrupt. */
 514	if (status & PCH_EWARN) {
 515		state = CAN_STATE_ERROR_WARNING;
 516		priv->can.can_stats.error_warning++;
 517		cf->can_id |= CAN_ERR_CRTL;
 518		if (((errc & PCH_REC) >> 8) > 96)
 519			cf->data[1] |= CAN_ERR_CRTL_RX_WARNING;
 520		if ((errc & PCH_TEC) > 96)
 521			cf->data[1] |= CAN_ERR_CRTL_TX_WARNING;
 522		netdev_dbg(ndev,
 523			"%s -> Error Counter is more than 96.\n", __func__);
 524	}
 525	/* Error passive interrupt. */
 526	if (status & PCH_EPASSIV) {
 527		priv->can.can_stats.error_passive++;
 528		state = CAN_STATE_ERROR_PASSIVE;
 529		cf->can_id |= CAN_ERR_CRTL;
 530		if (((errc & PCH_REC) >> 8) > 127)
 531			cf->data[1] |= CAN_ERR_CRTL_RX_PASSIVE;
 532		if ((errc & PCH_TEC) > 127)
 533			cf->data[1] |= CAN_ERR_CRTL_TX_PASSIVE;
 534		netdev_dbg(ndev,
 535			"%s -> CAN controller is ERROR PASSIVE .\n", __func__);
 536	}
 537
 538	lec = status & PCH_LEC_ALL;
 539	switch (lec) {
 540	case PCH_STUF_ERR:
 541		cf->data[2] |= CAN_ERR_PROT_STUFF;
 542		priv->can.can_stats.bus_error++;
 543		stats->rx_errors++;
 544		break;
 545	case PCH_FORM_ERR:
 546		cf->data[2] |= CAN_ERR_PROT_FORM;
 547		priv->can.can_stats.bus_error++;
 548		stats->rx_errors++;
 549		break;
 550	case PCH_ACK_ERR:
 551		cf->can_id |= CAN_ERR_ACK;
 552		priv->can.can_stats.bus_error++;
 553		stats->rx_errors++;
 554		break;
 555	case PCH_BIT1_ERR:
 556	case PCH_BIT0_ERR:
 557		cf->data[2] |= CAN_ERR_PROT_BIT;
 558		priv->can.can_stats.bus_error++;
 559		stats->rx_errors++;
 560		break;
 561	case PCH_CRC_ERR:
 562		cf->data[2] |= CAN_ERR_PROT_LOC_CRC_SEQ |
 563			       CAN_ERR_PROT_LOC_CRC_DEL;
 564		priv->can.can_stats.bus_error++;
 565		stats->rx_errors++;
 566		break;
 567	case PCH_LEC_ALL: /* Written by CPU. No error status */
 568		break;
 569	}
 570
 571	cf->data[6] = errc & PCH_TEC;
 572	cf->data[7] = (errc & PCH_REC) >> 8;
 573
 574	priv->can.state = state;
 575	netif_receive_skb(skb);
 576
 577	stats->rx_packets++;
 578	stats->rx_bytes += cf->can_dlc;
 579}
 580
 581static irqreturn_t pch_can_interrupt(int irq, void *dev_id)
 582{
 583	struct net_device *ndev = (struct net_device *)dev_id;
 584	struct pch_can_priv *priv = netdev_priv(ndev);
 585
 586	if (!pch_can_int_pending(priv))
 587		return IRQ_NONE;
 588
 589	pch_can_set_int_enables(priv, PCH_CAN_NONE);
 590	napi_schedule(&priv->napi);
 591	return IRQ_HANDLED;
 592}
 593
 594static void pch_fifo_thresh(struct pch_can_priv *priv, int obj_id)
 595{
 596	if (obj_id < PCH_FIFO_THRESH) {
 597		iowrite32(PCH_CMASK_RDWR | PCH_CMASK_CTRL |
 598			  PCH_CMASK_ARB, &priv->regs->ifregs[0].cmask);
 599
 600		/* Clearing the Dir bit. */
 601		pch_can_bit_clear(&priv->regs->ifregs[0].id2, PCH_ID2_DIR);
 602
 603		/* Clearing NewDat & IntPnd */
 604		pch_can_bit_clear(&priv->regs->ifregs[0].mcont,
 605				  PCH_IF_MCONT_INTPND);
 606		pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, obj_id);
 607	} else if (obj_id > PCH_FIFO_THRESH) {
 608		pch_can_int_clr(priv, obj_id);
 609	} else if (obj_id == PCH_FIFO_THRESH) {
 610		int cnt;
 611		for (cnt = 0; cnt < PCH_FIFO_THRESH; cnt++)
 612			pch_can_int_clr(priv, cnt + 1);
 613	}
 614}
 615
 616static void pch_can_rx_msg_lost(struct net_device *ndev, int obj_id)
 617{
 618	struct pch_can_priv *priv = netdev_priv(ndev);
 619	struct net_device_stats *stats = &(priv->ndev->stats);
 620	struct sk_buff *skb;
 621	struct can_frame *cf;
 622
 623	netdev_dbg(priv->ndev, "Msg Obj is overwritten.\n");
 624	pch_can_bit_clear(&priv->regs->ifregs[0].mcont,
 625			  PCH_IF_MCONT_MSGLOST);
 626	iowrite32(PCH_CMASK_RDWR | PCH_CMASK_CTRL,
 627		  &priv->regs->ifregs[0].cmask);
 628	pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, obj_id);
 629
 630	skb = alloc_can_err_skb(ndev, &cf);
 631	if (!skb)
 632		return;
 633
 634	cf->can_id |= CAN_ERR_CRTL;
 635	cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
 636	stats->rx_over_errors++;
 637	stats->rx_errors++;
 638
 639	netif_receive_skb(skb);
 640}
 641
 642static int pch_can_rx_normal(struct net_device *ndev, u32 obj_num, int quota)
 643{
 644	u32 reg;
 645	canid_t id;
 646	int rcv_pkts = 0;
 647	struct sk_buff *skb;
 648	struct can_frame *cf;
 649	struct pch_can_priv *priv = netdev_priv(ndev);
 650	struct net_device_stats *stats = &(priv->ndev->stats);
 651	int i;
 652	u32 id2;
 653	u16 data_reg;
 654
 655	do {
 656		/* Reading the message object from the Message RAM */
 657		iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[0].cmask);
 658		pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, obj_num);
 659
 660		/* Reading the MCONT register. */
 661		reg = ioread32(&priv->regs->ifregs[0].mcont);
 662
 663		if (reg & PCH_IF_MCONT_EOB)
 664			break;
 665
 666		/* If MsgLost bit set. */
 667		if (reg & PCH_IF_MCONT_MSGLOST) {
 668			pch_can_rx_msg_lost(ndev, obj_num);
 669			rcv_pkts++;
 670			quota--;
 671			obj_num++;
 672			continue;
 673		} else if (!(reg & PCH_IF_MCONT_NEWDAT)) {
 674			obj_num++;
 675			continue;
 676		}
 677
 678		skb = alloc_can_skb(priv->ndev, &cf);
 679		if (!skb) {
 680			netdev_err(ndev, "alloc_can_skb Failed\n");
 681			return rcv_pkts;
 682		}
 683
 684		/* Get Received data */
 685		id2 = ioread32(&priv->regs->ifregs[0].id2);
 686		if (id2 & PCH_ID2_XTD) {
 687			id = (ioread32(&priv->regs->ifregs[0].id1) & 0xffff);
 688			id |= (((id2) & 0x1fff) << 16);
 689			cf->can_id = id | CAN_EFF_FLAG;
 690		} else {
 691			id = (id2 >> 2) & CAN_SFF_MASK;
 692			cf->can_id = id;
 693		}
 694
 695		if (id2 & PCH_ID2_DIR)
 696			cf->can_id |= CAN_RTR_FLAG;
 697
 698		cf->can_dlc = get_can_dlc((ioread32(&priv->regs->
 699						    ifregs[0].mcont)) & 0xF);
 700
 701		for (i = 0; i < cf->can_dlc; i += 2) {
 702			data_reg = ioread16(&priv->regs->ifregs[0].data[i / 2]);
 703			cf->data[i] = data_reg;
 704			cf->data[i + 1] = data_reg >> 8;
 705		}
 706
 707		netif_receive_skb(skb);
 708		rcv_pkts++;
 709		stats->rx_packets++;
 710		quota--;
 711		stats->rx_bytes += cf->can_dlc;
 712
 713		pch_fifo_thresh(priv, obj_num);
 714		obj_num++;
 715	} while (quota > 0);
 716
 717	return rcv_pkts;
 718}
 719
 720static void pch_can_tx_complete(struct net_device *ndev, u32 int_stat)
 721{
 722	struct pch_can_priv *priv = netdev_priv(ndev);
 723	struct net_device_stats *stats = &(priv->ndev->stats);
 724	u32 dlc;
 725
 726	can_get_echo_skb(ndev, int_stat - PCH_RX_OBJ_END - 1);
 727	iowrite32(PCH_CMASK_RX_TX_GET | PCH_CMASK_CLRINTPND,
 728		  &priv->regs->ifregs[1].cmask);
 729	pch_can_rw_msg_obj(&priv->regs->ifregs[1].creq, int_stat);
 730	dlc = get_can_dlc(ioread32(&priv->regs->ifregs[1].mcont) &
 731			  PCH_IF_MCONT_DLC);
 732	stats->tx_bytes += dlc;
 733	stats->tx_packets++;
 734	if (int_stat == PCH_TX_OBJ_END)
 735		netif_wake_queue(ndev);
 736}
 737
 738static int pch_can_poll(struct napi_struct *napi, int quota)
 739{
 740	struct net_device *ndev = napi->dev;
 741	struct pch_can_priv *priv = netdev_priv(ndev);
 742	u32 int_stat;
 743	u32 reg_stat;
 744	int quota_save = quota;
 745
 746	int_stat = pch_can_int_pending(priv);
 747	if (!int_stat)
 748		goto end;
 749
 750	if (int_stat == PCH_STATUS_INT) {
 751		reg_stat = ioread32(&priv->regs->stat);
 752
 753		if ((reg_stat & (PCH_BUS_OFF | PCH_LEC_ALL)) &&
 754		   ((reg_stat & PCH_LEC_ALL) != PCH_LEC_ALL)) {
 755			pch_can_error(ndev, reg_stat);
 756			quota--;
 757		}
 758
 759		if (reg_stat & (PCH_TX_OK | PCH_RX_OK))
 760			pch_can_bit_clear(&priv->regs->stat,
 761					  reg_stat & (PCH_TX_OK | PCH_RX_OK));
 762
 763		int_stat = pch_can_int_pending(priv);
 764	}
 765
 766	if (quota == 0)
 767		goto end;
 768
 769	if ((int_stat >= PCH_RX_OBJ_START) && (int_stat <= PCH_RX_OBJ_END)) {
 770		quota -= pch_can_rx_normal(ndev, int_stat, quota);
 771	} else if ((int_stat >= PCH_TX_OBJ_START) &&
 772		   (int_stat <= PCH_TX_OBJ_END)) {
 773		/* Handle transmission interrupt */
 774		pch_can_tx_complete(ndev, int_stat);
 775	}
 776
 777end:
 778	napi_complete(napi);
 779	pch_can_set_int_enables(priv, PCH_CAN_ALL);
 780
 781	return quota_save - quota;
 782}
 783
 784static int pch_set_bittiming(struct net_device *ndev)
 785{
 786	struct pch_can_priv *priv = netdev_priv(ndev);
 787	const struct can_bittiming *bt = &priv->can.bittiming;
 788	u32 canbit;
 789	u32 bepe;
 790
 791	/* Setting the CCE bit for accessing the Can Timing register. */
 792	pch_can_bit_set(&priv->regs->cont, PCH_CTRL_CCE);
 793
 794	canbit = (bt->brp - 1) & PCH_MSK_BITT_BRP;
 795	canbit |= (bt->sjw - 1) << PCH_BIT_SJW_SHIFT;
 796	canbit |= (bt->phase_seg1 + bt->prop_seg - 1) << PCH_BIT_TSEG1_SHIFT;
 797	canbit |= (bt->phase_seg2 - 1) << PCH_BIT_TSEG2_SHIFT;
 798	bepe = ((bt->brp - 1) & PCH_MSK_BRPE_BRPE) >> PCH_BIT_BRPE_BRPE_SHIFT;
 799	iowrite32(canbit, &priv->regs->bitt);
 800	iowrite32(bepe, &priv->regs->brpe);
 801	pch_can_bit_clear(&priv->regs->cont, PCH_CTRL_CCE);
 802
 803	return 0;
 804}
 805
 806static void pch_can_start(struct net_device *ndev)
 807{
 808	struct pch_can_priv *priv = netdev_priv(ndev);
 809
 810	if (priv->can.state != CAN_STATE_STOPPED)
 811		pch_can_reset(priv);
 812
 813	pch_set_bittiming(ndev);
 814	pch_can_set_optmode(priv);
 815
 816	pch_can_set_tx_all(priv, 1);
 817	pch_can_set_rx_all(priv, 1);
 818
 819	/* Setting the CAN to run mode. */
 820	pch_can_set_run_mode(priv, PCH_CAN_RUN);
 821
 822	priv->can.state = CAN_STATE_ERROR_ACTIVE;
 823
 824	return;
 825}
 826
 827static int pch_can_do_set_mode(struct net_device *ndev, enum can_mode mode)
 828{
 829	int ret = 0;
 830
 831	switch (mode) {
 832	case CAN_MODE_START:
 833		pch_can_start(ndev);
 834		netif_wake_queue(ndev);
 835		break;
 836	default:
 837		ret = -EOPNOTSUPP;
 838		break;
 839	}
 840
 841	return ret;
 842}
 843
 844static int pch_can_open(struct net_device *ndev)
 845{
 846	struct pch_can_priv *priv = netdev_priv(ndev);
 847	int retval;
 848
 849	/* Regstering the interrupt. */
 850	retval = request_irq(priv->dev->irq, pch_can_interrupt, IRQF_SHARED,
 851			     ndev->name, ndev);
 852	if (retval) {
 853		netdev_err(ndev, "request_irq failed.\n");
 854		goto req_irq_err;
 855	}
 856
 857	/* Open common can device */
 858	retval = open_candev(ndev);
 859	if (retval) {
 860		netdev_err(ndev, "open_candev() failed %d\n", retval);
 861		goto err_open_candev;
 862	}
 863
 864	pch_can_init(priv);
 865	pch_can_start(ndev);
 866	napi_enable(&priv->napi);
 867	netif_start_queue(ndev);
 868
 869	return 0;
 870
 871err_open_candev:
 872	free_irq(priv->dev->irq, ndev);
 873req_irq_err:
 874	pch_can_release(priv);
 875
 876	return retval;
 877}
 878
 879static int pch_close(struct net_device *ndev)
 880{
 881	struct pch_can_priv *priv = netdev_priv(ndev);
 882
 883	netif_stop_queue(ndev);
 884	napi_disable(&priv->napi);
 885	pch_can_release(priv);
 886	free_irq(priv->dev->irq, ndev);
 887	close_candev(ndev);
 888	priv->can.state = CAN_STATE_STOPPED;
 889	return 0;
 890}
 891
 892static netdev_tx_t pch_xmit(struct sk_buff *skb, struct net_device *ndev)
 893{
 894	struct pch_can_priv *priv = netdev_priv(ndev);
 895	struct can_frame *cf = (struct can_frame *)skb->data;
 896	int tx_obj_no;
 897	int i;
 898	u32 id2;
 899
 900	if (can_dropped_invalid_skb(ndev, skb))
 901		return NETDEV_TX_OK;
 902
 903	tx_obj_no = priv->tx_obj;
 904	if (priv->tx_obj == PCH_TX_OBJ_END) {
 905		if (ioread32(&priv->regs->treq2) & PCH_TREQ2_TX_MASK)
 906			netif_stop_queue(ndev);
 907
 908		priv->tx_obj = PCH_TX_OBJ_START;
 909	} else {
 910		priv->tx_obj++;
 911	}
 912
 913	/* Setting the CMASK register. */
 914	pch_can_bit_set(&priv->regs->ifregs[1].cmask, PCH_CMASK_ALL);
 915
 916	/* If ID extended is set. */
 917	if (cf->can_id & CAN_EFF_FLAG) {
 918		iowrite32(cf->can_id & 0xffff, &priv->regs->ifregs[1].id1);
 919		id2 = ((cf->can_id >> 16) & 0x1fff) | PCH_ID2_XTD;
 920	} else {
 921		iowrite32(0, &priv->regs->ifregs[1].id1);
 922		id2 = (cf->can_id & CAN_SFF_MASK) << 2;
 923	}
 924
 925	id2 |= PCH_ID_MSGVAL;
 926
 927	/* If remote frame has to be transmitted.. */
 928	if (!(cf->can_id & CAN_RTR_FLAG))
 929		id2 |= PCH_ID2_DIR;
 930
 931	iowrite32(id2, &priv->regs->ifregs[1].id2);
 932
 933	/* Copy data to register */
 934	for (i = 0; i < cf->can_dlc; i += 2) {
 935		iowrite16(cf->data[i] | (cf->data[i + 1] << 8),
 936			  &priv->regs->ifregs[1].data[i / 2]);
 937	}
 938
 939	can_put_echo_skb(skb, ndev, tx_obj_no - PCH_RX_OBJ_END - 1);
 940
 941	/* Set the size of the data. Update if2_mcont */
 942	iowrite32(cf->can_dlc | PCH_IF_MCONT_NEWDAT | PCH_IF_MCONT_TXRQXT |
 943		  PCH_IF_MCONT_TXIE, &priv->regs->ifregs[1].mcont);
 944
 945	pch_can_rw_msg_obj(&priv->regs->ifregs[1].creq, tx_obj_no);
 946
 947	return NETDEV_TX_OK;
 948}
 949
 950static const struct net_device_ops pch_can_netdev_ops = {
 951	.ndo_open		= pch_can_open,
 952	.ndo_stop		= pch_close,
 953	.ndo_start_xmit		= pch_xmit,
 954};
 955
 956static void __devexit pch_can_remove(struct pci_dev *pdev)
 957{
 958	struct net_device *ndev = pci_get_drvdata(pdev);
 959	struct pch_can_priv *priv = netdev_priv(ndev);
 960
 961	unregister_candev(priv->ndev);
 962	if (priv->use_msi)
 963		pci_disable_msi(priv->dev);
 964	pci_release_regions(pdev);
 965	pci_disable_device(pdev);
 966	pci_set_drvdata(pdev, NULL);
 967	pch_can_reset(priv);
 968	pci_iounmap(pdev, priv->regs);
 969	free_candev(priv->ndev);
 970}
 971
 972#ifdef CONFIG_PM
 973static void pch_can_set_int_custom(struct pch_can_priv *priv)
 974{
 975	/* Clearing the IE, SIE and EIE bits of Can control register. */
 976	pch_can_bit_clear(&priv->regs->cont, PCH_CTRL_IE_SIE_EIE);
 977
 978	/* Appropriately setting them. */
 979	pch_can_bit_set(&priv->regs->cont,
 980			((priv->int_enables & PCH_MSK_CTRL_IE_SIE_EIE) << 1));
 981}
 982
 983/* This function retrieves interrupt enabled for the CAN device. */
 984static u32 pch_can_get_int_enables(struct pch_can_priv *priv)
 985{
 986	/* Obtaining the status of IE, SIE and EIE interrupt bits. */
 987	return (ioread32(&priv->regs->cont) & PCH_CTRL_IE_SIE_EIE) >> 1;
 988}
 989
 990static u32 pch_can_get_rxtx_ir(struct pch_can_priv *priv, u32 buff_num,
 991			       enum pch_ifreg dir)
 992{
 993	u32 ie, enable;
 994
 995	if (dir)
 996		ie = PCH_IF_MCONT_RXIE;
 997	else
 998		ie = PCH_IF_MCONT_TXIE;
 999
1000	iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[dir].cmask);
1001	pch_can_rw_msg_obj(&priv->regs->ifregs[dir].creq, buff_num);
1002
1003	if (((ioread32(&priv->regs->ifregs[dir].id2)) & PCH_ID_MSGVAL) &&
1004			((ioread32(&priv->regs->ifregs[dir].mcont)) & ie))
1005		enable = 1;
1006	else
1007		enable = 0;
1008
1009	return enable;
1010}
1011
1012static void pch_can_set_rx_buffer_link(struct pch_can_priv *priv,
1013				       u32 buffer_num, int set)
1014{
1015	iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[0].cmask);
1016	pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, buffer_num);
1017	iowrite32(PCH_CMASK_RDWR | PCH_CMASK_CTRL,
1018		  &priv->regs->ifregs[0].cmask);
1019	if (set)
1020		pch_can_bit_clear(&priv->regs->ifregs[0].mcont,
1021				  PCH_IF_MCONT_EOB);
1022	else
1023		pch_can_bit_set(&priv->regs->ifregs[0].mcont, PCH_IF_MCONT_EOB);
1024
1025	pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, buffer_num);
1026}
1027
1028static u32 pch_can_get_rx_buffer_link(struct pch_can_priv *priv, u32 buffer_num)
1029{
1030	u32 link;
1031
1032	iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[0].cmask);
1033	pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, buffer_num);
1034
1035	if (ioread32(&priv->regs->ifregs[0].mcont) & PCH_IF_MCONT_EOB)
1036		link = 0;
1037	else
1038		link = 1;
1039	return link;
1040}
1041
1042static int pch_can_get_buffer_status(struct pch_can_priv *priv)
1043{
1044	return (ioread32(&priv->regs->treq1) & 0xffff) |
1045	       (ioread32(&priv->regs->treq2) << 16);
1046}
1047
1048static int pch_can_suspend(struct pci_dev *pdev, pm_message_t state)
1049{
1050	int i;
1051	int retval;
1052	u32 buf_stat;	/* Variable for reading the transmit buffer status. */
1053	int counter = PCH_COUNTER_LIMIT;
1054
1055	struct net_device *dev = pci_get_drvdata(pdev);
1056	struct pch_can_priv *priv = netdev_priv(dev);
1057
1058	/* Stop the CAN controller */
1059	pch_can_set_run_mode(priv, PCH_CAN_STOP);
1060
1061	/* Indicate that we are aboutto/in suspend */
1062	priv->can.state = CAN_STATE_STOPPED;
1063
1064	/* Waiting for all transmission to complete. */
1065	while (counter) {
1066		buf_stat = pch_can_get_buffer_status(priv);
1067		if (!buf_stat)
1068			break;
1069		counter--;
1070		udelay(1);
1071	}
1072	if (!counter)
1073		dev_err(&pdev->dev, "%s -> Transmission time out.\n", __func__);
1074
1075	/* Save interrupt configuration and then disable them */
1076	priv->int_enables = pch_can_get_int_enables(priv);
1077	pch_can_set_int_enables(priv, PCH_CAN_DISABLE);
1078
1079	/* Save Tx buffer enable state */
1080	for (i = PCH_TX_OBJ_START; i <= PCH_TX_OBJ_END; i++)
1081		priv->tx_enable[i - 1] = pch_can_get_rxtx_ir(priv, i,
1082							     PCH_TX_IFREG);
1083
1084	/* Disable all Transmit buffers */
1085	pch_can_set_tx_all(priv, 0);
1086
1087	/* Save Rx buffer enable state */
1088	for (i = PCH_RX_OBJ_START; i <= PCH_RX_OBJ_END; i++) {
1089		priv->rx_enable[i - 1] = pch_can_get_rxtx_ir(priv, i,
1090							     PCH_RX_IFREG);
1091		priv->rx_link[i - 1] = pch_can_get_rx_buffer_link(priv, i);
1092	}
1093
1094	/* Disable all Receive buffers */
1095	pch_can_set_rx_all(priv, 0);
1096	retval = pci_save_state(pdev);
1097	if (retval) {
1098		dev_err(&pdev->dev, "pci_save_state failed.\n");
1099	} else {
1100		pci_enable_wake(pdev, PCI_D3hot, 0);
1101		pci_disable_device(pdev);
1102		pci_set_power_state(pdev, pci_choose_state(pdev, state));
1103	}
1104
1105	return retval;
1106}
1107
1108static int pch_can_resume(struct pci_dev *pdev)
1109{
1110	int i;
1111	int retval;
1112	struct net_device *dev = pci_get_drvdata(pdev);
1113	struct pch_can_priv *priv = netdev_priv(dev);
1114
1115	pci_set_power_state(pdev, PCI_D0);
1116	pci_restore_state(pdev);
1117	retval = pci_enable_device(pdev);
1118	if (retval) {
1119		dev_err(&pdev->dev, "pci_enable_device failed.\n");
1120		return retval;
1121	}
1122
1123	pci_enable_wake(pdev, PCI_D3hot, 0);
1124
1125	priv->can.state = CAN_STATE_ERROR_ACTIVE;
1126
1127	/* Disabling all interrupts. */
1128	pch_can_set_int_enables(priv, PCH_CAN_DISABLE);
1129
1130	/* Setting the CAN device in Stop Mode. */
1131	pch_can_set_run_mode(priv, PCH_CAN_STOP);
1132
1133	/* Configuring the transmit and receive buffers. */
1134	pch_can_config_rx_tx_buffers(priv);
1135
1136	/* Restore the CAN state */
1137	pch_set_bittiming(dev);
1138
1139	/* Listen/Active */
1140	pch_can_set_optmode(priv);
1141
1142	/* Enabling the transmit buffer. */
1143	for (i = PCH_TX_OBJ_START; i <= PCH_TX_OBJ_END; i++)
1144		pch_can_set_rxtx(priv, i, priv->tx_enable[i - 1], PCH_TX_IFREG);
1145
1146	/* Configuring the receive buffer and enabling them. */
1147	for (i = PCH_RX_OBJ_START; i <= PCH_RX_OBJ_END; i++) {
1148		/* Restore buffer link */
1149		pch_can_set_rx_buffer_link(priv, i, priv->rx_link[i - 1]);
1150
1151		/* Restore buffer enables */
1152		pch_can_set_rxtx(priv, i, priv->rx_enable[i - 1], PCH_RX_IFREG);
1153	}
1154
1155	/* Enable CAN Interrupts */
1156	pch_can_set_int_custom(priv);
1157
1158	/* Restore Run Mode */
1159	pch_can_set_run_mode(priv, PCH_CAN_RUN);
1160
1161	return retval;
1162}
1163#else
1164#define pch_can_suspend NULL
1165#define pch_can_resume NULL
1166#endif
1167
1168static int pch_can_get_berr_counter(const struct net_device *dev,
1169				    struct can_berr_counter *bec)
1170{
1171	struct pch_can_priv *priv = netdev_priv(dev);
1172	u32 errc = ioread32(&priv->regs->errc);
1173
1174	bec->txerr = errc & PCH_TEC;
1175	bec->rxerr = (errc & PCH_REC) >> 8;
1176
1177	return 0;
1178}
1179
1180static int __devinit pch_can_probe(struct pci_dev *pdev,
1181				   const struct pci_device_id *id)
1182{
1183	struct net_device *ndev;
1184	struct pch_can_priv *priv;
1185	int rc;
1186	void __iomem *addr;
1187
1188	rc = pci_enable_device(pdev);
1189	if (rc) {
1190		dev_err(&pdev->dev, "Failed pci_enable_device %d\n", rc);
1191		goto probe_exit_endev;
1192	}
1193
1194	rc = pci_request_regions(pdev, KBUILD_MODNAME);
1195	if (rc) {
1196		dev_err(&pdev->dev, "Failed pci_request_regions %d\n", rc);
1197		goto probe_exit_pcireq;
1198	}
1199
1200	addr = pci_iomap(pdev, 1, 0);
1201	if (!addr) {
1202		rc = -EIO;
1203		dev_err(&pdev->dev, "Failed pci_iomap\n");
1204		goto probe_exit_ipmap;
1205	}
1206
1207	ndev = alloc_candev(sizeof(struct pch_can_priv), PCH_TX_OBJ_END);
1208	if (!ndev) {
1209		rc = -ENOMEM;
1210		dev_err(&pdev->dev, "Failed alloc_candev\n");
1211		goto probe_exit_alloc_candev;
1212	}
1213
1214	priv = netdev_priv(ndev);
1215	priv->ndev = ndev;
1216	priv->regs = addr;
1217	priv->dev = pdev;
1218	priv->can.bittiming_const = &pch_can_bittiming_const;
1219	priv->can.do_set_mode = pch_can_do_set_mode;
1220	priv->can.do_get_berr_counter = pch_can_get_berr_counter;
1221	priv->can.ctrlmode_supported = CAN_CTRLMODE_LISTENONLY |
1222				       CAN_CTRLMODE_LOOPBACK;
1223	priv->tx_obj = PCH_TX_OBJ_START; /* Point head of Tx Obj */
1224
1225	ndev->irq = pdev->irq;
1226	ndev->flags |= IFF_ECHO;
1227
1228	pci_set_drvdata(pdev, ndev);
1229	SET_NETDEV_DEV(ndev, &pdev->dev);
1230	ndev->netdev_ops = &pch_can_netdev_ops;
1231	priv->can.clock.freq = PCH_CAN_CLK; /* Hz */
1232
1233	netif_napi_add(ndev, &priv->napi, pch_can_poll, PCH_RX_OBJ_END);
1234
1235	rc = pci_enable_msi(priv->dev);
1236	if (rc) {
1237		netdev_err(ndev, "PCH CAN opened without MSI\n");
1238		priv->use_msi = 0;
1239	} else {
1240		netdev_err(ndev, "PCH CAN opened with MSI\n");
1241		pci_set_master(pdev);
1242		priv->use_msi = 1;
1243	}
1244
1245	rc = register_candev(ndev);
1246	if (rc) {
1247		dev_err(&pdev->dev, "Failed register_candev %d\n", rc);
1248		goto probe_exit_reg_candev;
1249	}
1250
1251	return 0;
1252
1253probe_exit_reg_candev:
1254	if (priv->use_msi)
1255		pci_disable_msi(priv->dev);
1256	free_candev(ndev);
1257probe_exit_alloc_candev:
1258	pci_iounmap(pdev, addr);
1259probe_exit_ipmap:
1260	pci_release_regions(pdev);
1261probe_exit_pcireq:
1262	pci_disable_device(pdev);
1263probe_exit_endev:
1264	return rc;
1265}
1266
1267static struct pci_driver pch_can_pci_driver = {
1268	.name = "pch_can",
1269	.id_table = pch_pci_tbl,
1270	.probe = pch_can_probe,
1271	.remove = __devexit_p(pch_can_remove),
1272	.suspend = pch_can_suspend,
1273	.resume = pch_can_resume,
1274};
1275
1276static int __init pch_can_pci_init(void)
1277{
1278	return pci_register_driver(&pch_can_pci_driver);
1279}
1280module_init(pch_can_pci_init);
1281
1282static void __exit pch_can_pci_exit(void)
1283{
1284	pci_unregister_driver(&pch_can_pci_driver);
1285}
1286module_exit(pch_can_pci_exit);
1287
1288MODULE_DESCRIPTION("Intel EG20T PCH CAN(Controller Area Network) Driver");
1289MODULE_LICENSE("GPL v2");
1290MODULE_VERSION("0.94");