1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /******************************************************************************* 3 * 4 * CTU CAN FD IP Core 5 * 6 * Copyright (C) 2015-2018 Ondrej Ille <ondrej.ille@gmail.com> FEE CTU 7 * Copyright (C) 2018-2021 Ondrej Ille <ondrej.ille@gmail.com> self-funded 8 * Copyright (C) 2018-2019 Martin Jerabek <martin.jerabek01@gmail.com> FEE CTU 9 * Copyright (C) 2018-2022 Pavel Pisa <pisa@cmp.felk.cvut.cz> FEE CTU/self-funded 10 * 11 * Project advisors: 12 * Jiri Novak <jnovak@fel.cvut.cz> 13 * Pavel Pisa <pisa@cmp.felk.cvut.cz> 14 * 15 * Department of Measurement (http://meas.fel.cvut.cz/) 16 * Faculty of Electrical Engineering (http://www.fel.cvut.cz) 17 * Czech Technical University (http://www.cvut.cz/) 18 ******************************************************************************/ 19 20 #include <linux/clk.h> 21 #include <linux/errno.h> 22 #include <linux/ethtool.h> 23 #include <linux/init.h> 24 #include <linux/bitfield.h> 25 #include <linux/interrupt.h> 26 #include <linux/io.h> 27 #include <linux/kernel.h> 28 #include <linux/module.h> 29 #include <linux/skbuff.h> 30 #include <linux/string.h> 31 #include <linux/types.h> 32 #include <linux/can/error.h> 33 #include <linux/pm_runtime.h> 34 35 #include "ctucanfd.h" 36 #include "ctucanfd_kregs.h" 37 #include "ctucanfd_kframe.h" 38 39 #ifdef DEBUG 40 #define ctucan_netdev_dbg(ndev, args...) \ 41 netdev_dbg(ndev, args) 42 #else 43 #define ctucan_netdev_dbg(...) do { } while (0) 44 #endif 45 46 #define CTUCANFD_ID 0xCAFD 47 48 /* TX buffer rotation: 49 * - when a buffer transitions to empty state, rotate order and priorities 50 * - if more buffers seem to transition at the same time, rotate by the number of buffers 51 * - it may be assumed that buffers transition to empty state in FIFO order (because we manage 52 * priorities that way) 53 * - at frame filling, do not rotate anything, just increment buffer modulo counter 54 */ 55 56 #define CTUCANFD_FLAG_RX_FFW_BUFFERED 1 57 58 #define CTUCAN_STATE_TO_TEXT_ENTRY(st) \ 59 [st] = #st 60 61 enum ctucan_txtb_status { 62 TXT_NOT_EXIST = 0x0, 63 TXT_RDY = 0x1, 64 TXT_TRAN = 0x2, 65 TXT_ABTP = 0x3, 66 TXT_TOK = 0x4, 67 TXT_ERR = 0x6, 68 TXT_ABT = 0x7, 69 TXT_ETY = 0x8, 70 }; 71 72 enum ctucan_txtb_command { 73 TXT_CMD_SET_EMPTY = 0x01, 74 TXT_CMD_SET_READY = 0x02, 75 TXT_CMD_SET_ABORT = 0x04 76 }; 77 78 static const struct can_bittiming_const ctu_can_fd_bit_timing_max = { 79 .name = "ctu_can_fd", 80 .tseg1_min = 2, 81 .tseg1_max = 190, 82 .tseg2_min = 1, 83 .tseg2_max = 63, 84 .sjw_max = 31, 85 .brp_min = 1, 86 .brp_max = 8, 87 .brp_inc = 1, 88 }; 89 90 static const struct can_bittiming_const ctu_can_fd_bit_timing_data_max = { 91 .name = "ctu_can_fd", 92 .tseg1_min = 2, 93 .tseg1_max = 94, 94 .tseg2_min = 1, 95 .tseg2_max = 31, 96 .sjw_max = 31, 97 .brp_min = 1, 98 .brp_max = 2, 99 .brp_inc = 1, 100 }; 101 102 static const char * const ctucan_state_strings[CAN_STATE_MAX] = { 103 CTUCAN_STATE_TO_TEXT_ENTRY(CAN_STATE_ERROR_ACTIVE), 104 CTUCAN_STATE_TO_TEXT_ENTRY(CAN_STATE_ERROR_WARNING), 105 CTUCAN_STATE_TO_TEXT_ENTRY(CAN_STATE_ERROR_PASSIVE), 106 CTUCAN_STATE_TO_TEXT_ENTRY(CAN_STATE_BUS_OFF), 107 CTUCAN_STATE_TO_TEXT_ENTRY(CAN_STATE_STOPPED), 108 CTUCAN_STATE_TO_TEXT_ENTRY(CAN_STATE_SLEEPING) 109 }; 110 ctucan_write32_le(struct ctucan_priv * priv,enum ctu_can_fd_can_registers reg,u32 val)111 static void ctucan_write32_le(struct ctucan_priv *priv, 112 enum ctu_can_fd_can_registers reg, u32 val) 113 { 114 iowrite32(val, priv->mem_base + reg); 115 } 116 ctucan_write32_be(struct ctucan_priv * priv,enum ctu_can_fd_can_registers reg,u32 val)117 static void ctucan_write32_be(struct ctucan_priv *priv, 118 enum ctu_can_fd_can_registers reg, u32 val) 119 { 120 iowrite32be(val, priv->mem_base + reg); 121 } 122 ctucan_read32_le(struct ctucan_priv * priv,enum ctu_can_fd_can_registers reg)123 static u32 ctucan_read32_le(struct ctucan_priv *priv, 124 enum ctu_can_fd_can_registers reg) 125 { 126 return ioread32(priv->mem_base + reg); 127 } 128 ctucan_read32_be(struct ctucan_priv * priv,enum ctu_can_fd_can_registers reg)129 static u32 ctucan_read32_be(struct ctucan_priv *priv, 130 enum ctu_can_fd_can_registers reg) 131 { 132 return ioread32be(priv->mem_base + reg); 133 } 134 ctucan_write32(struct ctucan_priv * priv,enum ctu_can_fd_can_registers reg,u32 val)135 static void ctucan_write32(struct ctucan_priv *priv, enum ctu_can_fd_can_registers reg, u32 val) 136 { 137 priv->write_reg(priv, reg, val); 138 } 139 ctucan_read32(struct ctucan_priv * priv,enum ctu_can_fd_can_registers reg)140 static u32 ctucan_read32(struct ctucan_priv *priv, enum ctu_can_fd_can_registers reg) 141 { 142 return priv->read_reg(priv, reg); 143 } 144 ctucan_write_txt_buf(struct ctucan_priv * priv,enum ctu_can_fd_can_registers buf_base,u32 offset,u32 val)145 static void ctucan_write_txt_buf(struct ctucan_priv *priv, enum ctu_can_fd_can_registers buf_base, 146 u32 offset, u32 val) 147 { 148 priv->write_reg(priv, buf_base + offset, val); 149 } 150 151 #define CTU_CAN_FD_TXTNF(priv) (!!FIELD_GET(REG_STATUS_TXNF, ctucan_read32(priv, CTUCANFD_STATUS))) 152 #define CTU_CAN_FD_ENABLED(priv) (!!FIELD_GET(REG_MODE_ENA, ctucan_read32(priv, CTUCANFD_MODE))) 153 154 /** 155 * ctucan_state_to_str() - Converts CAN controller state code to corresponding text 156 * @state: CAN controller state code 157 * 158 * Return: Pointer to string representation of the error state 159 */ ctucan_state_to_str(enum can_state state)160 static const char *ctucan_state_to_str(enum can_state state) 161 { 162 const char *txt = NULL; 163 164 if (state >= 0 && state < CAN_STATE_MAX) 165 txt = ctucan_state_strings[state]; 166 return txt ? txt : "UNKNOWN"; 167 } 168 169 /** 170 * ctucan_reset() - Issues software reset request to CTU CAN FD 171 * @ndev: Pointer to net_device structure 172 * 173 * Return: 0 for success, -%ETIMEDOUT if CAN controller does not leave reset 174 */ ctucan_reset(struct net_device * ndev)175 static int ctucan_reset(struct net_device *ndev) 176 { 177 struct ctucan_priv *priv = netdev_priv(ndev); 178 int i = 100; 179 180 ctucan_write32(priv, CTUCANFD_MODE, REG_MODE_RST); 181 clear_bit(CTUCANFD_FLAG_RX_FFW_BUFFERED, &priv->drv_flags); 182 183 do { 184 u16 device_id = FIELD_GET(REG_DEVICE_ID_DEVICE_ID, 185 ctucan_read32(priv, CTUCANFD_DEVICE_ID)); 186 187 if (device_id == 0xCAFD) 188 return 0; 189 if (!i--) { 190 netdev_warn(ndev, "device did not leave reset\n"); 191 return -ETIMEDOUT; 192 } 193 usleep_range(100, 200); 194 } while (1); 195 } 196 197 /** 198 * ctucan_set_btr() - Sets CAN bus bit timing in CTU CAN FD 199 * @ndev: Pointer to net_device structure 200 * @bt: Pointer to Bit timing structure 201 * @nominal: True - Nominal bit timing, False - Data bit timing 202 * 203 * Return: 0 - OK, -%EPERM if controller is enabled 204 */ ctucan_set_btr(struct net_device * ndev,struct can_bittiming * bt,bool nominal)205 static int ctucan_set_btr(struct net_device *ndev, struct can_bittiming *bt, bool nominal) 206 { 207 struct ctucan_priv *priv = netdev_priv(ndev); 208 int max_ph1_len = 31; 209 u32 btr = 0; 210 u32 prop_seg = bt->prop_seg; 211 u32 phase_seg1 = bt->phase_seg1; 212 213 if (CTU_CAN_FD_ENABLED(priv)) { 214 netdev_err(ndev, "BUG! Cannot set bittiming - CAN is enabled\n"); 215 return -EPERM; 216 } 217 218 if (nominal) 219 max_ph1_len = 63; 220 221 /* The timing calculation functions have only constraints on tseg1, which is prop_seg + 222 * phase1_seg combined. tseg1 is then split in half and stored into prog_seg and phase_seg1. 223 * In CTU CAN FD, PROP is 6/7 bits wide but PH1 only 6/5, so we must re-distribute the 224 * values here. 225 */ 226 if (phase_seg1 > max_ph1_len) { 227 prop_seg += phase_seg1 - max_ph1_len; 228 phase_seg1 = max_ph1_len; 229 bt->prop_seg = prop_seg; 230 bt->phase_seg1 = phase_seg1; 231 } 232 233 if (nominal) { 234 btr = FIELD_PREP(REG_BTR_PROP, prop_seg); 235 btr |= FIELD_PREP(REG_BTR_PH1, phase_seg1); 236 btr |= FIELD_PREP(REG_BTR_PH2, bt->phase_seg2); 237 btr |= FIELD_PREP(REG_BTR_BRP, bt->brp); 238 btr |= FIELD_PREP(REG_BTR_SJW, bt->sjw); 239 240 ctucan_write32(priv, CTUCANFD_BTR, btr); 241 } else { 242 btr = FIELD_PREP(REG_BTR_FD_PROP_FD, prop_seg); 243 btr |= FIELD_PREP(REG_BTR_FD_PH1_FD, phase_seg1); 244 btr |= FIELD_PREP(REG_BTR_FD_PH2_FD, bt->phase_seg2); 245 btr |= FIELD_PREP(REG_BTR_FD_BRP_FD, bt->brp); 246 btr |= FIELD_PREP(REG_BTR_FD_SJW_FD, bt->sjw); 247 248 ctucan_write32(priv, CTUCANFD_BTR_FD, btr); 249 } 250 251 return 0; 252 } 253 254 /** 255 * ctucan_set_bittiming() - CAN set nominal bit timing routine 256 * @ndev: Pointer to net_device structure 257 * 258 * Return: 0 on success, -%EPERM on error 259 */ ctucan_set_bittiming(struct net_device * ndev)260 static int ctucan_set_bittiming(struct net_device *ndev) 261 { 262 struct ctucan_priv *priv = netdev_priv(ndev); 263 struct can_bittiming *bt = &priv->can.bittiming; 264 265 /* Note that bt may be modified here */ 266 return ctucan_set_btr(ndev, bt, true); 267 } 268 269 /** 270 * ctucan_set_data_bittiming() - CAN set data bit timing routine 271 * @ndev: Pointer to net_device structure 272 * 273 * Return: 0 on success, -%EPERM on error 274 */ ctucan_set_data_bittiming(struct net_device * ndev)275 static int ctucan_set_data_bittiming(struct net_device *ndev) 276 { 277 struct ctucan_priv *priv = netdev_priv(ndev); 278 struct can_bittiming *dbt = &priv->can.data_bittiming; 279 280 /* Note that dbt may be modified here */ 281 return ctucan_set_btr(ndev, dbt, false); 282 } 283 284 /** 285 * ctucan_set_secondary_sample_point() - Sets secondary sample point in CTU CAN FD 286 * @ndev: Pointer to net_device structure 287 * 288 * Return: 0 on success, -%EPERM if controller is enabled 289 */ ctucan_set_secondary_sample_point(struct net_device * ndev)290 static int ctucan_set_secondary_sample_point(struct net_device *ndev) 291 { 292 struct ctucan_priv *priv = netdev_priv(ndev); 293 struct can_bittiming *dbt = &priv->can.data_bittiming; 294 int ssp_offset = 0; 295 u32 ssp_cfg = 0; /* No SSP by default */ 296 297 if (CTU_CAN_FD_ENABLED(priv)) { 298 netdev_err(ndev, "BUG! Cannot set SSP - CAN is enabled\n"); 299 return -EPERM; 300 } 301 302 /* Use SSP for bit-rates above 1 Mbits/s */ 303 if (dbt->bitrate > 1000000) { 304 /* Calculate SSP in minimal time quanta */ 305 ssp_offset = (priv->can.clock.freq / 1000) * dbt->sample_point / dbt->bitrate; 306 307 if (ssp_offset > 127) { 308 netdev_warn(ndev, "SSP offset saturated to 127\n"); 309 ssp_offset = 127; 310 } 311 312 ssp_cfg = FIELD_PREP(REG_TRV_DELAY_SSP_OFFSET, ssp_offset); 313 ssp_cfg |= FIELD_PREP(REG_TRV_DELAY_SSP_SRC, 0x1); 314 } 315 316 ctucan_write32(priv, CTUCANFD_TRV_DELAY, ssp_cfg); 317 318 return 0; 319 } 320 321 /** 322 * ctucan_set_mode() - Sets CTU CAN FDs mode 323 * @priv: Pointer to private data 324 * @mode: Pointer to controller modes to be set 325 */ ctucan_set_mode(struct ctucan_priv * priv,const struct can_ctrlmode * mode)326 static void ctucan_set_mode(struct ctucan_priv *priv, const struct can_ctrlmode *mode) 327 { 328 u32 mode_reg = ctucan_read32(priv, CTUCANFD_MODE); 329 330 mode_reg = (mode->flags & CAN_CTRLMODE_LOOPBACK) ? 331 (mode_reg | REG_MODE_ILBP) : 332 (mode_reg & ~REG_MODE_ILBP); 333 334 mode_reg = (mode->flags & CAN_CTRLMODE_LISTENONLY) ? 335 (mode_reg | REG_MODE_BMM) : 336 (mode_reg & ~REG_MODE_BMM); 337 338 mode_reg = (mode->flags & CAN_CTRLMODE_FD) ? 339 (mode_reg | REG_MODE_FDE) : 340 (mode_reg & ~REG_MODE_FDE); 341 342 mode_reg = (mode->flags & CAN_CTRLMODE_PRESUME_ACK) ? 343 (mode_reg | REG_MODE_ACF) : 344 (mode_reg & ~REG_MODE_ACF); 345 346 mode_reg = (mode->flags & CAN_CTRLMODE_FD_NON_ISO) ? 347 (mode_reg | REG_MODE_NISOFD) : 348 (mode_reg & ~REG_MODE_NISOFD); 349 350 /* One shot mode supported indirectly via Retransmit limit */ 351 mode_reg &= ~FIELD_PREP(REG_MODE_RTRTH, 0xF); 352 mode_reg = (mode->flags & CAN_CTRLMODE_ONE_SHOT) ? 353 (mode_reg | REG_MODE_RTRLE) : 354 (mode_reg & ~REG_MODE_RTRLE); 355 356 /* Some bits fixed: 357 * TSTM - Off, User shall not be able to change REC/TEC by hand during operation 358 */ 359 mode_reg &= ~REG_MODE_TSTM; 360 361 ctucan_write32(priv, CTUCANFD_MODE, mode_reg); 362 } 363 364 /** 365 * ctucan_chip_start() - This routine starts the driver 366 * @ndev: Pointer to net_device structure 367 * 368 * Routine expects that chip is in reset state. It setups initial 369 * Tx buffers for FIFO priorities, sets bittiming, enables interrupts, 370 * switches core to operational mode and changes controller 371 * state to %CAN_STATE_STOPPED. 372 * 373 * Return: 0 on success and failure value on error 374 */ ctucan_chip_start(struct net_device * ndev)375 static int ctucan_chip_start(struct net_device *ndev) 376 { 377 struct ctucan_priv *priv = netdev_priv(ndev); 378 u32 int_ena, int_msk; 379 u32 mode_reg; 380 int err; 381 struct can_ctrlmode mode; 382 383 priv->txb_prio = 0x01234567; 384 priv->txb_head = 0; 385 priv->txb_tail = 0; 386 ctucan_write32(priv, CTUCANFD_TX_PRIORITY, priv->txb_prio); 387 388 /* Configure bit-rates and ssp */ 389 err = ctucan_set_bittiming(ndev); 390 if (err < 0) 391 return err; 392 393 err = ctucan_set_data_bittiming(ndev); 394 if (err < 0) 395 return err; 396 397 err = ctucan_set_secondary_sample_point(ndev); 398 if (err < 0) 399 return err; 400 401 /* Configure modes */ 402 mode.flags = priv->can.ctrlmode; 403 mode.mask = 0xFFFFFFFF; 404 ctucan_set_mode(priv, &mode); 405 406 /* Configure interrupts */ 407 int_ena = REG_INT_STAT_RBNEI | 408 REG_INT_STAT_TXBHCI | 409 REG_INT_STAT_EWLI | 410 REG_INT_STAT_FCSI; 411 412 /* Bus error reporting -> Allow Error/Arb.lost interrupts */ 413 if (priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING) { 414 int_ena |= REG_INT_STAT_ALI | 415 REG_INT_STAT_BEI; 416 } 417 418 int_msk = ~int_ena; /* Mask all disabled interrupts */ 419 420 /* It's after reset, so there is no need to clear anything */ 421 ctucan_write32(priv, CTUCANFD_INT_MASK_SET, int_msk); 422 ctucan_write32(priv, CTUCANFD_INT_ENA_SET, int_ena); 423 424 /* Controller enters ERROR_ACTIVE on initial FCSI */ 425 priv->can.state = CAN_STATE_STOPPED; 426 427 /* Enable the controller */ 428 mode_reg = ctucan_read32(priv, CTUCANFD_MODE); 429 mode_reg |= REG_MODE_ENA; 430 ctucan_write32(priv, CTUCANFD_MODE, mode_reg); 431 432 return 0; 433 } 434 435 /** 436 * ctucan_do_set_mode() - Sets mode of the driver 437 * @ndev: Pointer to net_device structure 438 * @mode: Tells the mode of the driver 439 * 440 * This check the drivers state and calls the corresponding modes to set. 441 * 442 * Return: 0 on success and failure value on error 443 */ ctucan_do_set_mode(struct net_device * ndev,enum can_mode mode)444 static int ctucan_do_set_mode(struct net_device *ndev, enum can_mode mode) 445 { 446 int ret; 447 448 switch (mode) { 449 case CAN_MODE_START: 450 ret = ctucan_reset(ndev); 451 if (ret < 0) 452 return ret; 453 ret = ctucan_chip_start(ndev); 454 if (ret < 0) { 455 netdev_err(ndev, "ctucan_chip_start failed!\n"); 456 return ret; 457 } 458 netif_wake_queue(ndev); 459 break; 460 default: 461 ret = -EOPNOTSUPP; 462 break; 463 } 464 465 return ret; 466 } 467 468 /** 469 * ctucan_get_tx_status() - Gets status of TXT buffer 470 * @priv: Pointer to private data 471 * @buf: Buffer index (0-based) 472 * 473 * Return: Status of TXT buffer 474 */ ctucan_get_tx_status(struct ctucan_priv * priv,u8 buf)475 static enum ctucan_txtb_status ctucan_get_tx_status(struct ctucan_priv *priv, u8 buf) 476 { 477 u32 tx_status = ctucan_read32(priv, CTUCANFD_TX_STATUS); 478 enum ctucan_txtb_status status = (tx_status >> (buf * 4)) & 0x7; 479 480 return status; 481 } 482 483 /** 484 * ctucan_is_txt_buf_writable() - Checks if frame can be inserted to TXT Buffer 485 * @priv: Pointer to private data 486 * @buf: Buffer index (0-based) 487 * 488 * Return: True - Frame can be inserted to TXT Buffer, False - If attempted, frame will not be 489 * inserted to TXT Buffer 490 */ ctucan_is_txt_buf_writable(struct ctucan_priv * priv,u8 buf)491 static bool ctucan_is_txt_buf_writable(struct ctucan_priv *priv, u8 buf) 492 { 493 enum ctucan_txtb_status buf_status; 494 495 buf_status = ctucan_get_tx_status(priv, buf); 496 if (buf_status == TXT_RDY || buf_status == TXT_TRAN || buf_status == TXT_ABTP) 497 return false; 498 499 return true; 500 } 501 502 /** 503 * ctucan_insert_frame() - Inserts frame to TXT buffer 504 * @priv: Pointer to private data 505 * @cf: Pointer to CAN frame to be inserted 506 * @buf: TXT Buffer index to which frame is inserted (0-based) 507 * @isfdf: True - CAN FD Frame, False - CAN 2.0 Frame 508 * 509 * Return: True - Frame inserted successfully 510 * False - Frame was not inserted due to one of: 511 * 1. TXT Buffer is not writable (it is in wrong state) 512 * 2. Invalid TXT buffer index 513 * 3. Invalid frame length 514 */ ctucan_insert_frame(struct ctucan_priv * priv,const struct canfd_frame * cf,u8 buf,bool isfdf)515 static bool ctucan_insert_frame(struct ctucan_priv *priv, const struct canfd_frame *cf, u8 buf, 516 bool isfdf) 517 { 518 u32 buf_base; 519 u32 ffw = 0; 520 u32 idw = 0; 521 unsigned int i; 522 523 if (buf >= priv->ntxbufs) 524 return false; 525 526 if (!ctucan_is_txt_buf_writable(priv, buf)) 527 return false; 528 529 if (cf->len > CANFD_MAX_DLEN) 530 return false; 531 532 /* Prepare Frame format */ 533 if (cf->can_id & CAN_RTR_FLAG) 534 ffw |= REG_FRAME_FORMAT_W_RTR; 535 536 if (cf->can_id & CAN_EFF_FLAG) 537 ffw |= REG_FRAME_FORMAT_W_IDE; 538 539 if (isfdf) { 540 ffw |= REG_FRAME_FORMAT_W_FDF; 541 if (cf->flags & CANFD_BRS) 542 ffw |= REG_FRAME_FORMAT_W_BRS; 543 } 544 545 ffw |= FIELD_PREP(REG_FRAME_FORMAT_W_DLC, can_fd_len2dlc(cf->len)); 546 547 /* Prepare identifier */ 548 if (cf->can_id & CAN_EFF_FLAG) 549 idw = cf->can_id & CAN_EFF_MASK; 550 else 551 idw = FIELD_PREP(REG_IDENTIFIER_W_IDENTIFIER_BASE, cf->can_id & CAN_SFF_MASK); 552 553 /* Write ID, Frame format, Don't write timestamp -> Time triggered transmission disabled */ 554 buf_base = (buf + 1) * 0x100; 555 ctucan_write_txt_buf(priv, buf_base, CTUCANFD_FRAME_FORMAT_W, ffw); 556 ctucan_write_txt_buf(priv, buf_base, CTUCANFD_IDENTIFIER_W, idw); 557 558 /* Write Data payload */ 559 if (!(cf->can_id & CAN_RTR_FLAG)) { 560 for (i = 0; i < cf->len; i += 4) { 561 u32 data = le32_to_cpu(*(__le32 *)(cf->data + i)); 562 563 ctucan_write_txt_buf(priv, buf_base, CTUCANFD_DATA_1_4_W + i, data); 564 } 565 } 566 567 return true; 568 } 569 570 /** 571 * ctucan_give_txtb_cmd() - Applies command on TXT buffer 572 * @priv: Pointer to private data 573 * @cmd: Command to give 574 * @buf: Buffer index (0-based) 575 */ ctucan_give_txtb_cmd(struct ctucan_priv * priv,enum ctucan_txtb_command cmd,u8 buf)576 static void ctucan_give_txtb_cmd(struct ctucan_priv *priv, enum ctucan_txtb_command cmd, u8 buf) 577 { 578 u32 tx_cmd = cmd; 579 580 tx_cmd |= 1 << (buf + 8); 581 ctucan_write32(priv, CTUCANFD_TX_COMMAND, tx_cmd); 582 } 583 584 /** 585 * ctucan_start_xmit() - Starts the transmission 586 * @skb: sk_buff pointer that contains data to be Txed 587 * @ndev: Pointer to net_device structure 588 * 589 * Invoked from upper layers to initiate transmission. Uses the next available free TXT Buffer and 590 * populates its fields to start the transmission. 591 * 592 * Return: %NETDEV_TX_OK on success, %NETDEV_TX_BUSY when no free TXT buffer is available, 593 * negative return values reserved for error cases 594 */ ctucan_start_xmit(struct sk_buff * skb,struct net_device * ndev)595 static netdev_tx_t ctucan_start_xmit(struct sk_buff *skb, struct net_device *ndev) 596 { 597 struct ctucan_priv *priv = netdev_priv(ndev); 598 struct canfd_frame *cf = (struct canfd_frame *)skb->data; 599 u32 txtb_id; 600 bool ok; 601 unsigned long flags; 602 603 if (can_dev_dropped_skb(ndev, skb)) 604 return NETDEV_TX_OK; 605 606 if (unlikely(!CTU_CAN_FD_TXTNF(priv))) { 607 netif_stop_queue(ndev); 608 netdev_err(ndev, "BUG!, no TXB free when queue awake!\n"); 609 return NETDEV_TX_BUSY; 610 } 611 612 txtb_id = priv->txb_head % priv->ntxbufs; 613 ctucan_netdev_dbg(ndev, "%s: using TXB#%u\n", __func__, txtb_id); 614 ok = ctucan_insert_frame(priv, cf, txtb_id, can_is_canfd_skb(skb)); 615 616 if (!ok) { 617 netdev_err(ndev, "BUG! TXNF set but cannot insert frame into TXTB! HW Bug?"); 618 kfree_skb(skb); 619 ndev->stats.tx_dropped++; 620 return NETDEV_TX_OK; 621 } 622 623 can_put_echo_skb(skb, ndev, txtb_id, 0); 624 625 spin_lock_irqsave(&priv->tx_lock, flags); 626 ctucan_give_txtb_cmd(priv, TXT_CMD_SET_READY, txtb_id); 627 priv->txb_head++; 628 629 /* Check if all TX buffers are full */ 630 if (!CTU_CAN_FD_TXTNF(priv)) 631 netif_stop_queue(ndev); 632 633 spin_unlock_irqrestore(&priv->tx_lock, flags); 634 635 return NETDEV_TX_OK; 636 } 637 638 /** 639 * ctucan_read_rx_frame() - Reads frame from RX FIFO 640 * @priv: Pointer to CTU CAN FD's private data 641 * @cf: Pointer to CAN frame struct 642 * @ffw: Previously read frame format word 643 * 644 * Note: Frame format word must be read separately and provided in 'ffw'. 645 */ ctucan_read_rx_frame(struct ctucan_priv * priv,struct canfd_frame * cf,u32 ffw)646 static void ctucan_read_rx_frame(struct ctucan_priv *priv, struct canfd_frame *cf, u32 ffw) 647 { 648 u32 idw; 649 unsigned int i; 650 unsigned int wc; 651 unsigned int len; 652 653 idw = ctucan_read32(priv, CTUCANFD_RX_DATA); 654 if (FIELD_GET(REG_FRAME_FORMAT_W_IDE, ffw)) 655 cf->can_id = (idw & CAN_EFF_MASK) | CAN_EFF_FLAG; 656 else 657 cf->can_id = (idw >> 18) & CAN_SFF_MASK; 658 659 /* BRS, ESI, RTR Flags */ 660 if (FIELD_GET(REG_FRAME_FORMAT_W_FDF, ffw)) { 661 if (FIELD_GET(REG_FRAME_FORMAT_W_BRS, ffw)) 662 cf->flags |= CANFD_BRS; 663 if (FIELD_GET(REG_FRAME_FORMAT_W_ESI_RSV, ffw)) 664 cf->flags |= CANFD_ESI; 665 } else if (FIELD_GET(REG_FRAME_FORMAT_W_RTR, ffw)) { 666 cf->can_id |= CAN_RTR_FLAG; 667 } 668 669 wc = FIELD_GET(REG_FRAME_FORMAT_W_RWCNT, ffw) - 3; 670 671 /* DLC */ 672 if (FIELD_GET(REG_FRAME_FORMAT_W_DLC, ffw) <= 8) { 673 len = FIELD_GET(REG_FRAME_FORMAT_W_DLC, ffw); 674 } else { 675 if (FIELD_GET(REG_FRAME_FORMAT_W_FDF, ffw)) 676 len = wc << 2; 677 else 678 len = 8; 679 } 680 cf->len = len; 681 if (unlikely(len > wc * 4)) 682 len = wc * 4; 683 684 /* Timestamp - Read and throw away */ 685 ctucan_read32(priv, CTUCANFD_RX_DATA); 686 ctucan_read32(priv, CTUCANFD_RX_DATA); 687 688 /* Data */ 689 for (i = 0; i < len; i += 4) { 690 u32 data = ctucan_read32(priv, CTUCANFD_RX_DATA); 691 *(__le32 *)(cf->data + i) = cpu_to_le32(data); 692 } 693 while (unlikely(i < wc * 4)) { 694 ctucan_read32(priv, CTUCANFD_RX_DATA); 695 i += 4; 696 } 697 } 698 699 /** 700 * ctucan_rx() - Called from CAN ISR to complete the received frame processing 701 * @ndev: Pointer to net_device structure 702 * 703 * This function is invoked from the CAN isr(poll) to process the Rx frames. It does minimal 704 * processing and invokes "netif_receive_skb" to complete further processing. 705 * Return: 1 when frame is passed to the network layer, 0 when the first frame word is read but 706 * system is out of free SKBs temporally and left code to resolve SKB allocation later, 707 * -%EAGAIN in a case of empty Rx FIFO. 708 */ ctucan_rx(struct net_device * ndev)709 static int ctucan_rx(struct net_device *ndev) 710 { 711 struct ctucan_priv *priv = netdev_priv(ndev); 712 struct net_device_stats *stats = &ndev->stats; 713 struct canfd_frame *cf; 714 struct sk_buff *skb; 715 u32 ffw; 716 717 if (test_bit(CTUCANFD_FLAG_RX_FFW_BUFFERED, &priv->drv_flags)) { 718 ffw = priv->rxfrm_first_word; 719 clear_bit(CTUCANFD_FLAG_RX_FFW_BUFFERED, &priv->drv_flags); 720 } else { 721 ffw = ctucan_read32(priv, CTUCANFD_RX_DATA); 722 } 723 724 if (!FIELD_GET(REG_FRAME_FORMAT_W_RWCNT, ffw)) 725 return -EAGAIN; 726 727 if (FIELD_GET(REG_FRAME_FORMAT_W_FDF, ffw)) 728 skb = alloc_canfd_skb(ndev, &cf); 729 else 730 skb = alloc_can_skb(ndev, (struct can_frame **)&cf); 731 732 if (unlikely(!skb)) { 733 priv->rxfrm_first_word = ffw; 734 set_bit(CTUCANFD_FLAG_RX_FFW_BUFFERED, &priv->drv_flags); 735 return 0; 736 } 737 738 ctucan_read_rx_frame(priv, cf, ffw); 739 740 stats->rx_bytes += cf->len; 741 stats->rx_packets++; 742 netif_receive_skb(skb); 743 744 return 1; 745 } 746 747 /** 748 * ctucan_read_fault_state() - Reads CTU CAN FDs fault confinement state. 749 * @priv: Pointer to private data 750 * 751 * Returns: Fault confinement state of controller 752 */ ctucan_read_fault_state(struct ctucan_priv * priv)753 static enum can_state ctucan_read_fault_state(struct ctucan_priv *priv) 754 { 755 u32 fs; 756 u32 rec_tec; 757 u32 ewl; 758 759 fs = ctucan_read32(priv, CTUCANFD_EWL); 760 rec_tec = ctucan_read32(priv, CTUCANFD_REC); 761 ewl = FIELD_GET(REG_EWL_EW_LIMIT, fs); 762 763 if (FIELD_GET(REG_EWL_ERA, fs)) { 764 if (ewl > FIELD_GET(REG_REC_REC_VAL, rec_tec) && 765 ewl > FIELD_GET(REG_REC_TEC_VAL, rec_tec)) 766 return CAN_STATE_ERROR_ACTIVE; 767 else 768 return CAN_STATE_ERROR_WARNING; 769 } else if (FIELD_GET(REG_EWL_ERP, fs)) { 770 return CAN_STATE_ERROR_PASSIVE; 771 } else if (FIELD_GET(REG_EWL_BOF, fs)) { 772 return CAN_STATE_BUS_OFF; 773 } 774 775 WARN(true, "Invalid error state"); 776 return CAN_STATE_ERROR_PASSIVE; 777 } 778 779 /** 780 * ctucan_get_rec_tec() - Reads REC/TEC counter values from controller 781 * @priv: Pointer to private data 782 * @bec: Pointer to Error counter structure 783 */ ctucan_get_rec_tec(struct ctucan_priv * priv,struct can_berr_counter * bec)784 static void ctucan_get_rec_tec(struct ctucan_priv *priv, struct can_berr_counter *bec) 785 { 786 u32 err_ctrs = ctucan_read32(priv, CTUCANFD_REC); 787 788 bec->rxerr = FIELD_GET(REG_REC_REC_VAL, err_ctrs); 789 bec->txerr = FIELD_GET(REG_REC_TEC_VAL, err_ctrs); 790 } 791 792 /** 793 * ctucan_err_interrupt() - Error frame ISR 794 * @ndev: net_device pointer 795 * @isr: interrupt status register value 796 * 797 * This is the CAN error interrupt and it will check the type of error and forward the error 798 * frame to upper layers. 799 */ ctucan_err_interrupt(struct net_device * ndev,u32 isr)800 static void ctucan_err_interrupt(struct net_device *ndev, u32 isr) 801 { 802 struct ctucan_priv *priv = netdev_priv(ndev); 803 struct net_device_stats *stats = &ndev->stats; 804 struct can_frame *cf; 805 struct sk_buff *skb; 806 enum can_state state; 807 struct can_berr_counter bec; 808 u32 err_capt_alc; 809 int dologerr = net_ratelimit(); 810 811 ctucan_get_rec_tec(priv, &bec); 812 state = ctucan_read_fault_state(priv); 813 err_capt_alc = ctucan_read32(priv, CTUCANFD_ERR_CAPT); 814 815 if (dologerr) 816 netdev_info(ndev, "%s: ISR = 0x%08x, rxerr %d, txerr %d, error type %lu, pos %lu, ALC id_field %lu, bit %lu\n", 817 __func__, isr, bec.rxerr, bec.txerr, 818 FIELD_GET(REG_ERR_CAPT_ERR_TYPE, err_capt_alc), 819 FIELD_GET(REG_ERR_CAPT_ERR_POS, err_capt_alc), 820 FIELD_GET(REG_ERR_CAPT_ALC_ID_FIELD, err_capt_alc), 821 FIELD_GET(REG_ERR_CAPT_ALC_BIT, err_capt_alc)); 822 823 skb = alloc_can_err_skb(ndev, &cf); 824 825 /* EWLI: error warning limit condition met 826 * FCSI: fault confinement state changed 827 * ALI: arbitration lost (just informative) 828 * BEI: bus error interrupt 829 */ 830 if (FIELD_GET(REG_INT_STAT_FCSI, isr) || FIELD_GET(REG_INT_STAT_EWLI, isr)) { 831 netdev_info(ndev, "state changes from %s to %s\n", 832 ctucan_state_to_str(priv->can.state), 833 ctucan_state_to_str(state)); 834 835 if (priv->can.state == state) 836 netdev_warn(ndev, 837 "current and previous state is the same! (missed interrupt?)\n"); 838 839 priv->can.state = state; 840 switch (state) { 841 case CAN_STATE_BUS_OFF: 842 priv->can.can_stats.bus_off++; 843 can_bus_off(ndev); 844 if (skb) 845 cf->can_id |= CAN_ERR_BUSOFF; 846 break; 847 case CAN_STATE_ERROR_PASSIVE: 848 priv->can.can_stats.error_passive++; 849 if (skb) { 850 cf->can_id |= CAN_ERR_CRTL | CAN_ERR_CNT; 851 cf->data[1] = (bec.rxerr > 127) ? 852 CAN_ERR_CRTL_RX_PASSIVE : 853 CAN_ERR_CRTL_TX_PASSIVE; 854 cf->data[6] = bec.txerr; 855 cf->data[7] = bec.rxerr; 856 } 857 break; 858 case CAN_STATE_ERROR_WARNING: 859 priv->can.can_stats.error_warning++; 860 if (skb) { 861 cf->can_id |= CAN_ERR_CRTL | CAN_ERR_CNT; 862 cf->data[1] |= (bec.txerr > bec.rxerr) ? 863 CAN_ERR_CRTL_TX_WARNING : 864 CAN_ERR_CRTL_RX_WARNING; 865 cf->data[6] = bec.txerr; 866 cf->data[7] = bec.rxerr; 867 } 868 break; 869 case CAN_STATE_ERROR_ACTIVE: 870 if (skb) { 871 cf->can_id |= CAN_ERR_CNT; 872 cf->data[1] = CAN_ERR_CRTL_ACTIVE; 873 cf->data[6] = bec.txerr; 874 cf->data[7] = bec.rxerr; 875 } 876 break; 877 default: 878 netdev_warn(ndev, "unhandled error state (%d:%s)!\n", 879 state, ctucan_state_to_str(state)); 880 break; 881 } 882 } 883 884 /* Check for Arbitration Lost interrupt */ 885 if (FIELD_GET(REG_INT_STAT_ALI, isr)) { 886 if (dologerr) 887 netdev_info(ndev, "arbitration lost\n"); 888 priv->can.can_stats.arbitration_lost++; 889 if (skb) { 890 cf->can_id |= CAN_ERR_LOSTARB; 891 cf->data[0] = CAN_ERR_LOSTARB_UNSPEC; 892 } 893 } 894 895 /* Check for Bus Error interrupt */ 896 if (FIELD_GET(REG_INT_STAT_BEI, isr)) { 897 netdev_info(ndev, "bus error\n"); 898 priv->can.can_stats.bus_error++; 899 stats->rx_errors++; 900 if (skb) { 901 cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR; 902 cf->data[2] = CAN_ERR_PROT_UNSPEC; 903 cf->data[3] = CAN_ERR_PROT_LOC_UNSPEC; 904 } 905 } 906 907 if (skb) { 908 stats->rx_packets++; 909 stats->rx_bytes += cf->can_dlc; 910 netif_rx(skb); 911 } 912 } 913 914 /** 915 * ctucan_rx_poll() - Poll routine for rx packets (NAPI) 916 * @napi: NAPI structure pointer 917 * @quota: Max number of rx packets to be processed. 918 * 919 * This is the poll routine for rx part. It will process the packets maximux quota value. 920 * 921 * Return: Number of packets received 922 */ ctucan_rx_poll(struct napi_struct * napi,int quota)923 static int ctucan_rx_poll(struct napi_struct *napi, int quota) 924 { 925 struct net_device *ndev = napi->dev; 926 struct ctucan_priv *priv = netdev_priv(ndev); 927 int work_done = 0; 928 u32 status; 929 u32 framecnt; 930 int res = 1; 931 932 framecnt = FIELD_GET(REG_RX_STATUS_RXFRC, ctucan_read32(priv, CTUCANFD_RX_STATUS)); 933 while (framecnt && work_done < quota && res > 0) { 934 res = ctucan_rx(ndev); 935 work_done++; 936 framecnt = FIELD_GET(REG_RX_STATUS_RXFRC, ctucan_read32(priv, CTUCANFD_RX_STATUS)); 937 } 938 939 /* Check for RX FIFO Overflow */ 940 status = ctucan_read32(priv, CTUCANFD_STATUS); 941 if (FIELD_GET(REG_STATUS_DOR, status)) { 942 struct net_device_stats *stats = &ndev->stats; 943 struct can_frame *cf; 944 struct sk_buff *skb; 945 946 netdev_info(ndev, "rx_poll: rx fifo overflow\n"); 947 stats->rx_over_errors++; 948 stats->rx_errors++; 949 skb = alloc_can_err_skb(ndev, &cf); 950 if (skb) { 951 cf->can_id |= CAN_ERR_CRTL; 952 cf->data[1] |= CAN_ERR_CRTL_RX_OVERFLOW; 953 stats->rx_packets++; 954 stats->rx_bytes += cf->can_dlc; 955 netif_rx(skb); 956 } 957 958 /* Clear Data Overrun */ 959 ctucan_write32(priv, CTUCANFD_COMMAND, REG_COMMAND_CDO); 960 } 961 962 if (!framecnt && res != 0) { 963 if (napi_complete_done(napi, work_done)) { 964 /* Clear and enable RBNEI. It is level-triggered, so 965 * there is no race condition. 966 */ 967 ctucan_write32(priv, CTUCANFD_INT_STAT, REG_INT_STAT_RBNEI); 968 ctucan_write32(priv, CTUCANFD_INT_MASK_CLR, REG_INT_STAT_RBNEI); 969 } 970 } 971 972 return work_done; 973 } 974 975 /** 976 * ctucan_rotate_txb_prio() - Rotates priorities of TXT Buffers 977 * @ndev: net_device pointer 978 */ ctucan_rotate_txb_prio(struct net_device * ndev)979 static void ctucan_rotate_txb_prio(struct net_device *ndev) 980 { 981 struct ctucan_priv *priv = netdev_priv(ndev); 982 u32 prio = priv->txb_prio; 983 984 prio = (prio << 4) | ((prio >> ((priv->ntxbufs - 1) * 4)) & 0xF); 985 ctucan_netdev_dbg(ndev, "%s: from 0x%08x to 0x%08x\n", __func__, priv->txb_prio, prio); 986 priv->txb_prio = prio; 987 ctucan_write32(priv, CTUCANFD_TX_PRIORITY, prio); 988 } 989 990 /** 991 * ctucan_tx_interrupt() - Tx done Isr 992 * @ndev: net_device pointer 993 */ ctucan_tx_interrupt(struct net_device * ndev)994 static void ctucan_tx_interrupt(struct net_device *ndev) 995 { 996 struct ctucan_priv *priv = netdev_priv(ndev); 997 struct net_device_stats *stats = &ndev->stats; 998 bool first = true; 999 bool some_buffers_processed; 1000 unsigned long flags; 1001 enum ctucan_txtb_status txtb_status; 1002 u32 txtb_id; 1003 1004 /* read tx_status 1005 * if txb[n].finished (bit 2) 1006 * if ok -> echo 1007 * if error / aborted -> ?? (find how to handle oneshot mode) 1008 * txb_tail++ 1009 */ 1010 do { 1011 spin_lock_irqsave(&priv->tx_lock, flags); 1012 1013 some_buffers_processed = false; 1014 while ((int)(priv->txb_head - priv->txb_tail) > 0) { 1015 txtb_id = priv->txb_tail % priv->ntxbufs; 1016 txtb_status = ctucan_get_tx_status(priv, txtb_id); 1017 1018 ctucan_netdev_dbg(ndev, "TXI: TXB#%u: status 0x%x\n", txtb_id, txtb_status); 1019 1020 switch (txtb_status) { 1021 case TXT_TOK: 1022 ctucan_netdev_dbg(ndev, "TXT_OK\n"); 1023 stats->tx_bytes += can_get_echo_skb(ndev, txtb_id, NULL); 1024 stats->tx_packets++; 1025 break; 1026 case TXT_ERR: 1027 /* This indicated that retransmit limit has been reached. Obviously 1028 * we should not echo the frame, but also not indicate any kind of 1029 * error. If desired, it was already reported (possible multiple 1030 * times) on each arbitration lost. 1031 */ 1032 netdev_warn(ndev, "TXB in Error state\n"); 1033 can_free_echo_skb(ndev, txtb_id, NULL); 1034 stats->tx_dropped++; 1035 break; 1036 case TXT_ABT: 1037 /* Same as for TXT_ERR, only with different cause. We *could* 1038 * re-queue the frame, but multiqueue/abort is not supported yet 1039 * anyway. 1040 */ 1041 netdev_warn(ndev, "TXB in Aborted state\n"); 1042 can_free_echo_skb(ndev, txtb_id, NULL); 1043 stats->tx_dropped++; 1044 break; 1045 default: 1046 /* Bug only if the first buffer is not finished, otherwise it is 1047 * pretty much expected. 1048 */ 1049 if (first) { 1050 netdev_err(ndev, 1051 "BUG: TXB#%u not in a finished state (0x%x)!\n", 1052 txtb_id, txtb_status); 1053 spin_unlock_irqrestore(&priv->tx_lock, flags); 1054 /* do not clear nor wake */ 1055 return; 1056 } 1057 goto clear; 1058 } 1059 priv->txb_tail++; 1060 first = false; 1061 some_buffers_processed = true; 1062 /* Adjust priorities *before* marking the buffer as empty. */ 1063 ctucan_rotate_txb_prio(ndev); 1064 ctucan_give_txtb_cmd(priv, TXT_CMD_SET_EMPTY, txtb_id); 1065 } 1066 clear: 1067 spin_unlock_irqrestore(&priv->tx_lock, flags); 1068 1069 /* If no buffers were processed this time, we cannot clear - that would introduce 1070 * a race condition. 1071 */ 1072 if (some_buffers_processed) { 1073 /* Clear the interrupt again. We do not want to receive again interrupt for 1074 * the buffer already handled. If it is the last finished one then it would 1075 * cause log of spurious interrupt. 1076 */ 1077 ctucan_write32(priv, CTUCANFD_INT_STAT, REG_INT_STAT_TXBHCI); 1078 } 1079 } while (some_buffers_processed); 1080 1081 spin_lock_irqsave(&priv->tx_lock, flags); 1082 1083 /* Check if at least one TX buffer is free */ 1084 if (CTU_CAN_FD_TXTNF(priv)) 1085 netif_wake_queue(ndev); 1086 1087 spin_unlock_irqrestore(&priv->tx_lock, flags); 1088 } 1089 1090 /** 1091 * ctucan_interrupt() - CAN Isr 1092 * @irq: irq number 1093 * @dev_id: device id pointer 1094 * 1095 * This is the CTU CAN FD ISR. It checks for the type of interrupt 1096 * and invokes the corresponding ISR. 1097 * 1098 * Return: 1099 * IRQ_NONE - If CAN device is in sleep mode, IRQ_HANDLED otherwise 1100 */ ctucan_interrupt(int irq,void * dev_id)1101 static irqreturn_t ctucan_interrupt(int irq, void *dev_id) 1102 { 1103 struct net_device *ndev = (struct net_device *)dev_id; 1104 struct ctucan_priv *priv = netdev_priv(ndev); 1105 u32 isr, icr; 1106 u32 imask; 1107 int irq_loops; 1108 1109 for (irq_loops = 0; irq_loops < 10000; irq_loops++) { 1110 /* Get the interrupt status */ 1111 isr = ctucan_read32(priv, CTUCANFD_INT_STAT); 1112 1113 if (!isr) 1114 return irq_loops ? IRQ_HANDLED : IRQ_NONE; 1115 1116 /* Receive Buffer Not Empty Interrupt */ 1117 if (FIELD_GET(REG_INT_STAT_RBNEI, isr)) { 1118 ctucan_netdev_dbg(ndev, "RXBNEI\n"); 1119 /* Mask RXBNEI the first, then clear interrupt and schedule NAPI. Even if 1120 * another IRQ fires, RBNEI will always be 0 (masked). 1121 */ 1122 icr = REG_INT_STAT_RBNEI; 1123 ctucan_write32(priv, CTUCANFD_INT_MASK_SET, icr); 1124 ctucan_write32(priv, CTUCANFD_INT_STAT, icr); 1125 napi_schedule(&priv->napi); 1126 } 1127 1128 /* TXT Buffer HW Command Interrupt */ 1129 if (FIELD_GET(REG_INT_STAT_TXBHCI, isr)) { 1130 ctucan_netdev_dbg(ndev, "TXBHCI\n"); 1131 /* Cleared inside */ 1132 ctucan_tx_interrupt(ndev); 1133 } 1134 1135 /* Error interrupts */ 1136 if (FIELD_GET(REG_INT_STAT_EWLI, isr) || 1137 FIELD_GET(REG_INT_STAT_FCSI, isr) || 1138 FIELD_GET(REG_INT_STAT_ALI, isr)) { 1139 icr = isr & (REG_INT_STAT_EWLI | REG_INT_STAT_FCSI | REG_INT_STAT_ALI); 1140 1141 ctucan_netdev_dbg(ndev, "some ERR interrupt: clearing 0x%08x\n", icr); 1142 ctucan_write32(priv, CTUCANFD_INT_STAT, icr); 1143 ctucan_err_interrupt(ndev, isr); 1144 } 1145 /* Ignore RI, TI, LFI, RFI, BSI */ 1146 } 1147 1148 netdev_err(ndev, "%s: stuck interrupt (isr=0x%08x), stopping\n", __func__, isr); 1149 1150 if (FIELD_GET(REG_INT_STAT_TXBHCI, isr)) { 1151 int i; 1152 1153 netdev_err(ndev, "txb_head=0x%08x txb_tail=0x%08x\n", 1154 priv->txb_head, priv->txb_tail); 1155 for (i = 0; i < priv->ntxbufs; i++) { 1156 u32 status = ctucan_get_tx_status(priv, i); 1157 1158 netdev_err(ndev, "txb[%d] txb status=0x%08x\n", i, status); 1159 } 1160 } 1161 1162 imask = 0xffffffff; 1163 ctucan_write32(priv, CTUCANFD_INT_ENA_CLR, imask); 1164 ctucan_write32(priv, CTUCANFD_INT_MASK_SET, imask); 1165 1166 return IRQ_HANDLED; 1167 } 1168 1169 /** 1170 * ctucan_chip_stop() - Driver stop routine 1171 * @ndev: Pointer to net_device structure 1172 * 1173 * This is the drivers stop routine. It will disable the 1174 * interrupts and disable the controller. 1175 */ ctucan_chip_stop(struct net_device * ndev)1176 static void ctucan_chip_stop(struct net_device *ndev) 1177 { 1178 struct ctucan_priv *priv = netdev_priv(ndev); 1179 u32 mask = 0xffffffff; 1180 u32 mode; 1181 1182 /* Disable interrupts and disable CAN */ 1183 ctucan_write32(priv, CTUCANFD_INT_ENA_CLR, mask); 1184 ctucan_write32(priv, CTUCANFD_INT_MASK_SET, mask); 1185 mode = ctucan_read32(priv, CTUCANFD_MODE); 1186 mode &= ~REG_MODE_ENA; 1187 ctucan_write32(priv, CTUCANFD_MODE, mode); 1188 1189 priv->can.state = CAN_STATE_STOPPED; 1190 } 1191 1192 /** 1193 * ctucan_open() - Driver open routine 1194 * @ndev: Pointer to net_device structure 1195 * 1196 * This is the driver open routine. 1197 * Return: 0 on success and failure value on error 1198 */ ctucan_open(struct net_device * ndev)1199 static int ctucan_open(struct net_device *ndev) 1200 { 1201 struct ctucan_priv *priv = netdev_priv(ndev); 1202 int ret; 1203 1204 ret = pm_runtime_get_sync(priv->dev); 1205 if (ret < 0) { 1206 netdev_err(ndev, "%s: pm_runtime_get failed(%d)\n", 1207 __func__, ret); 1208 pm_runtime_put_noidle(priv->dev); 1209 return ret; 1210 } 1211 1212 ret = ctucan_reset(ndev); 1213 if (ret < 0) 1214 goto err_reset; 1215 1216 /* Common open */ 1217 ret = open_candev(ndev); 1218 if (ret) { 1219 netdev_warn(ndev, "open_candev failed!\n"); 1220 goto err_open; 1221 } 1222 1223 ret = request_irq(ndev->irq, ctucan_interrupt, priv->irq_flags, ndev->name, ndev); 1224 if (ret < 0) { 1225 netdev_err(ndev, "irq allocation for CAN failed\n"); 1226 goto err_irq; 1227 } 1228 1229 ret = ctucan_chip_start(ndev); 1230 if (ret < 0) { 1231 netdev_err(ndev, "ctucan_chip_start failed!\n"); 1232 goto err_chip_start; 1233 } 1234 1235 netdev_info(ndev, "ctu_can_fd device registered\n"); 1236 napi_enable(&priv->napi); 1237 netif_start_queue(ndev); 1238 1239 return 0; 1240 1241 err_chip_start: 1242 free_irq(ndev->irq, ndev); 1243 err_irq: 1244 close_candev(ndev); 1245 err_open: 1246 err_reset: 1247 pm_runtime_put(priv->dev); 1248 1249 return ret; 1250 } 1251 1252 /** 1253 * ctucan_close() - Driver close routine 1254 * @ndev: Pointer to net_device structure 1255 * 1256 * Return: 0 always 1257 */ ctucan_close(struct net_device * ndev)1258 static int ctucan_close(struct net_device *ndev) 1259 { 1260 struct ctucan_priv *priv = netdev_priv(ndev); 1261 1262 netif_stop_queue(ndev); 1263 napi_disable(&priv->napi); 1264 ctucan_chip_stop(ndev); 1265 free_irq(ndev->irq, ndev); 1266 close_candev(ndev); 1267 1268 pm_runtime_put(priv->dev); 1269 1270 return 0; 1271 } 1272 1273 /** 1274 * ctucan_get_berr_counter() - error counter routine 1275 * @ndev: Pointer to net_device structure 1276 * @bec: Pointer to can_berr_counter structure 1277 * 1278 * This is the driver error counter routine. 1279 * Return: 0 on success and failure value on error 1280 */ ctucan_get_berr_counter(const struct net_device * ndev,struct can_berr_counter * bec)1281 static int ctucan_get_berr_counter(const struct net_device *ndev, struct can_berr_counter *bec) 1282 { 1283 struct ctucan_priv *priv = netdev_priv(ndev); 1284 int ret; 1285 1286 ret = pm_runtime_get_sync(priv->dev); 1287 if (ret < 0) { 1288 netdev_err(ndev, "%s: pm_runtime_get failed(%d)\n", __func__, ret); 1289 pm_runtime_put_noidle(priv->dev); 1290 return ret; 1291 } 1292 1293 ctucan_get_rec_tec(priv, bec); 1294 pm_runtime_put(priv->dev); 1295 1296 return 0; 1297 } 1298 1299 static const struct net_device_ops ctucan_netdev_ops = { 1300 .ndo_open = ctucan_open, 1301 .ndo_stop = ctucan_close, 1302 .ndo_start_xmit = ctucan_start_xmit, 1303 .ndo_change_mtu = can_change_mtu, 1304 }; 1305 1306 static const struct ethtool_ops ctucan_ethtool_ops = { 1307 .get_ts_info = ethtool_op_get_ts_info, 1308 }; 1309 ctucan_suspend(struct device * dev)1310 int ctucan_suspend(struct device *dev) 1311 { 1312 struct net_device *ndev = dev_get_drvdata(dev); 1313 struct ctucan_priv *priv = netdev_priv(ndev); 1314 1315 if (netif_running(ndev)) { 1316 netif_stop_queue(ndev); 1317 netif_device_detach(ndev); 1318 } 1319 1320 priv->can.state = CAN_STATE_SLEEPING; 1321 1322 return 0; 1323 } 1324 EXPORT_SYMBOL(ctucan_suspend); 1325 ctucan_resume(struct device * dev)1326 int ctucan_resume(struct device *dev) 1327 { 1328 struct net_device *ndev = dev_get_drvdata(dev); 1329 struct ctucan_priv *priv = netdev_priv(ndev); 1330 1331 priv->can.state = CAN_STATE_ERROR_ACTIVE; 1332 1333 if (netif_running(ndev)) { 1334 netif_device_attach(ndev); 1335 netif_start_queue(ndev); 1336 } 1337 1338 return 0; 1339 } 1340 EXPORT_SYMBOL(ctucan_resume); 1341 ctucan_probe_common(struct device * dev,void __iomem * addr,int irq,unsigned int ntxbufs,unsigned long can_clk_rate,int pm_enable_call,void (* set_drvdata_fnc)(struct device * dev,struct net_device * ndev))1342 int ctucan_probe_common(struct device *dev, void __iomem *addr, int irq, unsigned int ntxbufs, 1343 unsigned long can_clk_rate, int pm_enable_call, 1344 void (*set_drvdata_fnc)(struct device *dev, struct net_device *ndev)) 1345 { 1346 struct ctucan_priv *priv; 1347 struct net_device *ndev; 1348 int ret; 1349 1350 /* Create a CAN device instance */ 1351 ndev = alloc_candev(sizeof(struct ctucan_priv), ntxbufs); 1352 if (!ndev) 1353 return -ENOMEM; 1354 1355 priv = netdev_priv(ndev); 1356 spin_lock_init(&priv->tx_lock); 1357 INIT_LIST_HEAD(&priv->peers_on_pdev); 1358 priv->ntxbufs = ntxbufs; 1359 priv->dev = dev; 1360 priv->can.bittiming_const = &ctu_can_fd_bit_timing_max; 1361 priv->can.data_bittiming_const = &ctu_can_fd_bit_timing_data_max; 1362 priv->can.do_set_mode = ctucan_do_set_mode; 1363 1364 /* Needed for timing adjustment to be performed as soon as possible */ 1365 priv->can.do_set_bittiming = ctucan_set_bittiming; 1366 priv->can.do_set_data_bittiming = ctucan_set_data_bittiming; 1367 1368 priv->can.do_get_berr_counter = ctucan_get_berr_counter; 1369 priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK 1370 | CAN_CTRLMODE_LISTENONLY 1371 | CAN_CTRLMODE_FD 1372 | CAN_CTRLMODE_PRESUME_ACK 1373 | CAN_CTRLMODE_BERR_REPORTING 1374 | CAN_CTRLMODE_FD_NON_ISO 1375 | CAN_CTRLMODE_ONE_SHOT; 1376 priv->mem_base = addr; 1377 1378 /* Get IRQ for the device */ 1379 ndev->irq = irq; 1380 ndev->flags |= IFF_ECHO; /* We support local echo */ 1381 1382 if (set_drvdata_fnc) 1383 set_drvdata_fnc(dev, ndev); 1384 SET_NETDEV_DEV(ndev, dev); 1385 ndev->netdev_ops = &ctucan_netdev_ops; 1386 ndev->ethtool_ops = &ctucan_ethtool_ops; 1387 1388 /* Getting the can_clk info */ 1389 if (!can_clk_rate) { 1390 priv->can_clk = devm_clk_get(dev, NULL); 1391 if (IS_ERR(priv->can_clk)) { 1392 dev_err(dev, "Device clock not found.\n"); 1393 ret = PTR_ERR(priv->can_clk); 1394 goto err_free; 1395 } 1396 can_clk_rate = clk_get_rate(priv->can_clk); 1397 } 1398 1399 priv->write_reg = ctucan_write32_le; 1400 priv->read_reg = ctucan_read32_le; 1401 1402 if (pm_enable_call) 1403 pm_runtime_enable(dev); 1404 ret = pm_runtime_get_sync(dev); 1405 if (ret < 0) { 1406 netdev_err(ndev, "%s: pm_runtime_get failed(%d)\n", 1407 __func__, ret); 1408 pm_runtime_put_noidle(priv->dev); 1409 goto err_pmdisable; 1410 } 1411 1412 /* Check for big-endianity and set according IO-accessors */ 1413 if ((ctucan_read32(priv, CTUCANFD_DEVICE_ID) & 0xFFFF) != CTUCANFD_ID) { 1414 priv->write_reg = ctucan_write32_be; 1415 priv->read_reg = ctucan_read32_be; 1416 if ((ctucan_read32(priv, CTUCANFD_DEVICE_ID) & 0xFFFF) != CTUCANFD_ID) { 1417 netdev_err(ndev, "CTU_CAN_FD signature not found\n"); 1418 ret = -ENODEV; 1419 goto err_deviceoff; 1420 } 1421 } 1422 1423 ret = ctucan_reset(ndev); 1424 if (ret < 0) 1425 goto err_deviceoff; 1426 1427 priv->can.clock.freq = can_clk_rate; 1428 1429 netif_napi_add(ndev, &priv->napi, ctucan_rx_poll); 1430 1431 ret = register_candev(ndev); 1432 if (ret) { 1433 dev_err(dev, "fail to register failed (err=%d)\n", ret); 1434 goto err_deviceoff; 1435 } 1436 1437 pm_runtime_put(dev); 1438 1439 netdev_dbg(ndev, "mem_base=0x%p irq=%d clock=%d, no. of txt buffers:%d\n", 1440 priv->mem_base, ndev->irq, priv->can.clock.freq, priv->ntxbufs); 1441 1442 return 0; 1443 1444 err_deviceoff: 1445 pm_runtime_put(priv->dev); 1446 err_pmdisable: 1447 if (pm_enable_call) 1448 pm_runtime_disable(dev); 1449 err_free: 1450 list_del_init(&priv->peers_on_pdev); 1451 free_candev(ndev); 1452 return ret; 1453 } 1454 EXPORT_SYMBOL(ctucan_probe_common); 1455 1456 MODULE_LICENSE("GPL"); 1457 MODULE_AUTHOR("Martin Jerabek <martin.jerabek01@gmail.com>"); 1458 MODULE_AUTHOR("Pavel Pisa <pisa@cmp.felk.cvut.cz>"); 1459 MODULE_AUTHOR("Ondrej Ille <ondrej.ille@gmail.com>"); 1460 MODULE_DESCRIPTION("CTU CAN FD interface"); 1461