drivers/net/can/pch_can.c

   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
  98 enum pch_ifreg {
  99         PCH_RX_IFREG,
 100         PCH_TX_IFREG,
 101 };
 102
 103 enum 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
 113 enum 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
 122 struct 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
 134 struct 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
 160 struct 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
 174 static 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
 186 static const struct pci_device_id pch_pci_tbl[] = {
 187         {PCI_VENDOR_ID_INTEL, 0x8818, PCI_ANY_ID, PCI_ANY_ID,},
 188         {0,}
 189 };
 190 MODULE_DEVICE_TABLE(pci, pch_pci_tbl);
 191
 192 static inline void pch_can_bit_set(void __iomem *addr, u32 mask)
 193 {
 194         iowrite32(ioread32(addr) | mask, addr);
 195 }
 196
 197 static inline void pch_can_bit_clear(void __iomem *addr, u32 mask)
 198 {
 199         iowrite32(ioread32(addr) & ~mask, addr);
 200 }
 201
 202 static 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
 220 static 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
 234 static 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
 251 static 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
 273 static 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
 304 static 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
 313 static 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
 322 static u32 pch_can_int_pending(struct pch_can_priv *priv)
 323 {
 324         return ioread32(&priv->regs->intr) & 0xffff;
 325 }
 326
 327 static 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
 349 static 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
 405 static 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
 420 static 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. */
 436 static 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
 472 static 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
 479 static 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
 569 static 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
 582 static 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
 604 static 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
 630 static 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
 708 static 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);
 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
 726 static 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
 765 end:
 766         napi_complete(napi);
 767         pch_can_set_int_enables(priv, PCH_CAN_ALL);
 768
 769         return quota_save - quota;
 770 }
 771
 772 static 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
 794 static 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
 815 static 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
 832 static 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
 859 err_open_candev:
 860         free_irq(priv->dev->irq, ndev);
 861 req_irq_err:
 862         pch_can_release(priv);
 863
 864         return retval;
 865 }
 866
 867 static 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
 880 static 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);
 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
 938 static 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
 945 static 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
 960 static 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. */
 971 static 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
 977 static 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
 999 static 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
1015 static 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
1030 static 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
1036 static 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
1087 static 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
1132 static 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
1144 static 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
1217 probe_exit_reg_candev:
1218         if (priv->use_msi)
1219                 pci_disable_msi(priv->dev);
1220         free_candev(ndev);
1221 probe_exit_alloc_candev:
1222         pci_iounmap(pdev, addr);
1223 probe_exit_ipmap:
1224         pci_release_regions(pdev);
1225 probe_exit_pcireq:
1226         pci_disable_device(pdev);
1227 probe_exit_endev:
1228         return rc;
1229 }
1230
1231 static SIMPLE_DEV_PM_OPS(pch_can_pm_ops,
1232                          pch_can_suspend,
1233                          pch_can_resume);
1234
1235 static 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
1243 module_pci_driver(pch_can_pci_driver);
1244
1245 MODULE_DESCRIPTION("Intel EG20T PCH CAN(Controller Area Network) Driver");
1246 MODULE_LICENSE("GPL v2");
1247 MODULE_VERSION("0.94");