1 /* 2 * (C) Copyright 2009 3 * Vipin Kumar, ST Micoelectronics, vipin.kumar@st.com. 4 * 5 * SPDX-License-Identifier: GPL-2.0+ 6 */ 7 8 #include <common.h> 9 #include <dm.h> 10 #include <i2c.h> 11 #include <pci.h> 12 #include <asm/io.h> 13 #include "designware_i2c.h" 14 15 struct dw_scl_sda_cfg { 16 u32 ss_hcnt; 17 u32 fs_hcnt; 18 u32 ss_lcnt; 19 u32 fs_lcnt; 20 u32 sda_hold; 21 }; 22 23 #ifdef CONFIG_X86 24 /* BayTrail HCNT/LCNT/SDA hold time */ 25 static struct dw_scl_sda_cfg byt_config = { 26 .ss_hcnt = 0x200, 27 .fs_hcnt = 0x55, 28 .ss_lcnt = 0x200, 29 .fs_lcnt = 0x99, 30 .sda_hold = 0x6, 31 }; 32 #endif 33 34 struct dw_i2c { 35 struct i2c_regs *regs; 36 struct dw_scl_sda_cfg *scl_sda_cfg; 37 }; 38 39 #ifdef CONFIG_SYS_I2C_DW_ENABLE_STATUS_UNSUPPORTED 40 static void dw_i2c_enable(struct i2c_regs *i2c_base, bool enable) 41 { 42 u32 ena = enable ? IC_ENABLE_0B : 0; 43 44 writel(ena, &i2c_base->ic_enable); 45 } 46 #else 47 static void dw_i2c_enable(struct i2c_regs *i2c_base, bool enable) 48 { 49 u32 ena = enable ? IC_ENABLE_0B : 0; 50 int timeout = 100; 51 52 do { 53 writel(ena, &i2c_base->ic_enable); 54 if ((readl(&i2c_base->ic_enable_status) & IC_ENABLE_0B) == ena) 55 return; 56 57 /* 58 * Wait 10 times the signaling period of the highest I2C 59 * transfer supported by the driver (for 400KHz this is 60 * 25us) as described in the DesignWare I2C databook. 61 */ 62 udelay(25); 63 } while (timeout--); 64 65 printf("timeout in %sabling I2C adapter\n", enable ? "en" : "dis"); 66 } 67 #endif 68 69 /* 70 * i2c_set_bus_speed - Set the i2c speed 71 * @speed: required i2c speed 72 * 73 * Set the i2c speed. 74 */ 75 static unsigned int __dw_i2c_set_bus_speed(struct i2c_regs *i2c_base, 76 struct dw_scl_sda_cfg *scl_sda_cfg, 77 unsigned int speed) 78 { 79 unsigned int cntl; 80 unsigned int hcnt, lcnt; 81 int i2c_spd; 82 83 if (speed >= I2C_MAX_SPEED) 84 i2c_spd = IC_SPEED_MODE_MAX; 85 else if (speed >= I2C_FAST_SPEED) 86 i2c_spd = IC_SPEED_MODE_FAST; 87 else 88 i2c_spd = IC_SPEED_MODE_STANDARD; 89 90 /* to set speed cltr must be disabled */ 91 dw_i2c_enable(i2c_base, false); 92 93 cntl = (readl(&i2c_base->ic_con) & (~IC_CON_SPD_MSK)); 94 95 switch (i2c_spd) { 96 #ifndef CONFIG_X86 /* No High-speed for BayTrail yet */ 97 case IC_SPEED_MODE_MAX: 98 cntl |= IC_CON_SPD_SS; 99 if (scl_sda_cfg) { 100 hcnt = scl_sda_cfg->fs_hcnt; 101 lcnt = scl_sda_cfg->fs_lcnt; 102 } else { 103 hcnt = (IC_CLK * MIN_HS_SCL_HIGHTIME) / NANO_TO_MICRO; 104 lcnt = (IC_CLK * MIN_HS_SCL_LOWTIME) / NANO_TO_MICRO; 105 } 106 writel(hcnt, &i2c_base->ic_hs_scl_hcnt); 107 writel(lcnt, &i2c_base->ic_hs_scl_lcnt); 108 break; 109 #endif 110 111 case IC_SPEED_MODE_STANDARD: 112 cntl |= IC_CON_SPD_SS; 113 if (scl_sda_cfg) { 114 hcnt = scl_sda_cfg->ss_hcnt; 115 lcnt = scl_sda_cfg->ss_lcnt; 116 } else { 117 hcnt = (IC_CLK * MIN_SS_SCL_HIGHTIME) / NANO_TO_MICRO; 118 lcnt = (IC_CLK * MIN_SS_SCL_LOWTIME) / NANO_TO_MICRO; 119 } 120 writel(hcnt, &i2c_base->ic_ss_scl_hcnt); 121 writel(lcnt, &i2c_base->ic_ss_scl_lcnt); 122 break; 123 124 case IC_SPEED_MODE_FAST: 125 default: 126 cntl |= IC_CON_SPD_FS; 127 if (scl_sda_cfg) { 128 hcnt = scl_sda_cfg->fs_hcnt; 129 lcnt = scl_sda_cfg->fs_lcnt; 130 } else { 131 hcnt = (IC_CLK * MIN_FS_SCL_HIGHTIME) / NANO_TO_MICRO; 132 lcnt = (IC_CLK * MIN_FS_SCL_LOWTIME) / NANO_TO_MICRO; 133 } 134 writel(hcnt, &i2c_base->ic_fs_scl_hcnt); 135 writel(lcnt, &i2c_base->ic_fs_scl_lcnt); 136 break; 137 } 138 139 writel(cntl, &i2c_base->ic_con); 140 141 /* Configure SDA Hold Time if required */ 142 if (scl_sda_cfg) 143 writel(scl_sda_cfg->sda_hold, &i2c_base->ic_sda_hold); 144 145 /* Enable back i2c now speed set */ 146 dw_i2c_enable(i2c_base, true); 147 148 return 0; 149 } 150 151 /* 152 * i2c_setaddress - Sets the target slave address 153 * @i2c_addr: target i2c address 154 * 155 * Sets the target slave address. 156 */ 157 static void i2c_setaddress(struct i2c_regs *i2c_base, unsigned int i2c_addr) 158 { 159 /* Disable i2c */ 160 dw_i2c_enable(i2c_base, false); 161 162 writel(i2c_addr, &i2c_base->ic_tar); 163 164 /* Enable i2c */ 165 dw_i2c_enable(i2c_base, true); 166 } 167 168 /* 169 * i2c_flush_rxfifo - Flushes the i2c RX FIFO 170 * 171 * Flushes the i2c RX FIFO 172 */ 173 static void i2c_flush_rxfifo(struct i2c_regs *i2c_base) 174 { 175 while (readl(&i2c_base->ic_status) & IC_STATUS_RFNE) 176 readl(&i2c_base->ic_cmd_data); 177 } 178 179 /* 180 * i2c_wait_for_bb - Waits for bus busy 181 * 182 * Waits for bus busy 183 */ 184 static int i2c_wait_for_bb(struct i2c_regs *i2c_base) 185 { 186 unsigned long start_time_bb = get_timer(0); 187 188 while ((readl(&i2c_base->ic_status) & IC_STATUS_MA) || 189 !(readl(&i2c_base->ic_status) & IC_STATUS_TFE)) { 190 191 /* Evaluate timeout */ 192 if (get_timer(start_time_bb) > (unsigned long)(I2C_BYTE_TO_BB)) 193 return 1; 194 } 195 196 return 0; 197 } 198 199 static int i2c_xfer_init(struct i2c_regs *i2c_base, uchar chip, uint addr, 200 int alen) 201 { 202 if (i2c_wait_for_bb(i2c_base)) 203 return 1; 204 205 i2c_setaddress(i2c_base, chip); 206 while (alen) { 207 alen--; 208 /* high byte address going out first */ 209 writel((addr >> (alen * 8)) & 0xff, 210 &i2c_base->ic_cmd_data); 211 } 212 return 0; 213 } 214 215 static int i2c_xfer_finish(struct i2c_regs *i2c_base) 216 { 217 ulong start_stop_det = get_timer(0); 218 219 while (1) { 220 if ((readl(&i2c_base->ic_raw_intr_stat) & IC_STOP_DET)) { 221 readl(&i2c_base->ic_clr_stop_det); 222 break; 223 } else if (get_timer(start_stop_det) > I2C_STOPDET_TO) { 224 break; 225 } 226 } 227 228 if (i2c_wait_for_bb(i2c_base)) { 229 printf("Timed out waiting for bus\n"); 230 return 1; 231 } 232 233 i2c_flush_rxfifo(i2c_base); 234 235 return 0; 236 } 237 238 /* 239 * i2c_read - Read from i2c memory 240 * @chip: target i2c address 241 * @addr: address to read from 242 * @alen: 243 * @buffer: buffer for read data 244 * @len: no of bytes to be read 245 * 246 * Read from i2c memory. 247 */ 248 static int __dw_i2c_read(struct i2c_regs *i2c_base, u8 dev, uint addr, 249 int alen, u8 *buffer, int len) 250 { 251 unsigned long start_time_rx; 252 unsigned int active = 0; 253 254 #ifdef CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW 255 /* 256 * EEPROM chips that implement "address overflow" are ones 257 * like Catalyst 24WC04/08/16 which has 9/10/11 bits of 258 * address and the extra bits end up in the "chip address" 259 * bit slots. This makes a 24WC08 (1Kbyte) chip look like 260 * four 256 byte chips. 261 * 262 * Note that we consider the length of the address field to 263 * still be one byte because the extra address bits are 264 * hidden in the chip address. 265 */ 266 dev |= ((addr >> (alen * 8)) & CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW); 267 addr &= ~(CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW << (alen * 8)); 268 269 debug("%s: fix addr_overflow: dev %02x addr %02x\n", __func__, dev, 270 addr); 271 #endif 272 273 if (i2c_xfer_init(i2c_base, dev, addr, alen)) 274 return 1; 275 276 start_time_rx = get_timer(0); 277 while (len) { 278 if (!active) { 279 /* 280 * Avoid writing to ic_cmd_data multiple times 281 * in case this loop spins too quickly and the 282 * ic_status RFNE bit isn't set after the first 283 * write. Subsequent writes to ic_cmd_data can 284 * trigger spurious i2c transfer. 285 */ 286 if (len == 1) 287 writel(IC_CMD | IC_STOP, &i2c_base->ic_cmd_data); 288 else 289 writel(IC_CMD, &i2c_base->ic_cmd_data); 290 active = 1; 291 } 292 293 if (readl(&i2c_base->ic_status) & IC_STATUS_RFNE) { 294 *buffer++ = (uchar)readl(&i2c_base->ic_cmd_data); 295 len--; 296 start_time_rx = get_timer(0); 297 active = 0; 298 } else if (get_timer(start_time_rx) > I2C_BYTE_TO) { 299 return 1; 300 } 301 } 302 303 return i2c_xfer_finish(i2c_base); 304 } 305 306 /* 307 * i2c_write - Write to i2c memory 308 * @chip: target i2c address 309 * @addr: address to read from 310 * @alen: 311 * @buffer: buffer for read data 312 * @len: no of bytes to be read 313 * 314 * Write to i2c memory. 315 */ 316 static int __dw_i2c_write(struct i2c_regs *i2c_base, u8 dev, uint addr, 317 int alen, u8 *buffer, int len) 318 { 319 int nb = len; 320 unsigned long start_time_tx; 321 322 #ifdef CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW 323 /* 324 * EEPROM chips that implement "address overflow" are ones 325 * like Catalyst 24WC04/08/16 which has 9/10/11 bits of 326 * address and the extra bits end up in the "chip address" 327 * bit slots. This makes a 24WC08 (1Kbyte) chip look like 328 * four 256 byte chips. 329 * 330 * Note that we consider the length of the address field to 331 * still be one byte because the extra address bits are 332 * hidden in the chip address. 333 */ 334 dev |= ((addr >> (alen * 8)) & CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW); 335 addr &= ~(CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW << (alen * 8)); 336 337 debug("%s: fix addr_overflow: dev %02x addr %02x\n", __func__, dev, 338 addr); 339 #endif 340 341 if (i2c_xfer_init(i2c_base, dev, addr, alen)) 342 return 1; 343 344 start_time_tx = get_timer(0); 345 while (len) { 346 if (readl(&i2c_base->ic_status) & IC_STATUS_TFNF) { 347 if (--len == 0) { 348 writel(*buffer | IC_STOP, 349 &i2c_base->ic_cmd_data); 350 } else { 351 writel(*buffer, &i2c_base->ic_cmd_data); 352 } 353 buffer++; 354 start_time_tx = get_timer(0); 355 356 } else if (get_timer(start_time_tx) > (nb * I2C_BYTE_TO)) { 357 printf("Timed out. i2c write Failed\n"); 358 return 1; 359 } 360 } 361 362 return i2c_xfer_finish(i2c_base); 363 } 364 365 /* 366 * __dw_i2c_init - Init function 367 * @speed: required i2c speed 368 * @slaveaddr: slave address for the device 369 * 370 * Initialization function. 371 */ 372 static void __dw_i2c_init(struct i2c_regs *i2c_base, int speed, int slaveaddr) 373 { 374 /* Disable i2c */ 375 dw_i2c_enable(i2c_base, false); 376 377 writel((IC_CON_SD | IC_CON_SPD_FS | IC_CON_MM), &i2c_base->ic_con); 378 writel(IC_RX_TL, &i2c_base->ic_rx_tl); 379 writel(IC_TX_TL, &i2c_base->ic_tx_tl); 380 writel(IC_STOP_DET, &i2c_base->ic_intr_mask); 381 #ifndef CONFIG_DM_I2C 382 __dw_i2c_set_bus_speed(i2c_base, NULL, speed); 383 writel(slaveaddr, &i2c_base->ic_sar); 384 #endif 385 386 /* Enable i2c */ 387 dw_i2c_enable(i2c_base, true); 388 } 389 390 #ifndef CONFIG_DM_I2C 391 /* 392 * The legacy I2C functions. These need to get removed once 393 * all users of this driver are converted to DM. 394 */ 395 static struct i2c_regs *i2c_get_base(struct i2c_adapter *adap) 396 { 397 switch (adap->hwadapnr) { 398 #if CONFIG_SYS_I2C_BUS_MAX >= 4 399 case 3: 400 return (struct i2c_regs *)CONFIG_SYS_I2C_BASE3; 401 #endif 402 #if CONFIG_SYS_I2C_BUS_MAX >= 3 403 case 2: 404 return (struct i2c_regs *)CONFIG_SYS_I2C_BASE2; 405 #endif 406 #if CONFIG_SYS_I2C_BUS_MAX >= 2 407 case 1: 408 return (struct i2c_regs *)CONFIG_SYS_I2C_BASE1; 409 #endif 410 case 0: 411 return (struct i2c_regs *)CONFIG_SYS_I2C_BASE; 412 default: 413 printf("Wrong I2C-adapter number %d\n", adap->hwadapnr); 414 } 415 416 return NULL; 417 } 418 419 static unsigned int dw_i2c_set_bus_speed(struct i2c_adapter *adap, 420 unsigned int speed) 421 { 422 adap->speed = speed; 423 return __dw_i2c_set_bus_speed(i2c_get_base(adap), NULL, speed); 424 } 425 426 static void dw_i2c_init(struct i2c_adapter *adap, int speed, int slaveaddr) 427 { 428 __dw_i2c_init(i2c_get_base(adap), speed, slaveaddr); 429 } 430 431 static int dw_i2c_read(struct i2c_adapter *adap, u8 dev, uint addr, 432 int alen, u8 *buffer, int len) 433 { 434 return __dw_i2c_read(i2c_get_base(adap), dev, addr, alen, buffer, len); 435 } 436 437 static int dw_i2c_write(struct i2c_adapter *adap, u8 dev, uint addr, 438 int alen, u8 *buffer, int len) 439 { 440 return __dw_i2c_write(i2c_get_base(adap), dev, addr, alen, buffer, len); 441 } 442 443 /* dw_i2c_probe - Probe the i2c chip */ 444 static int dw_i2c_probe(struct i2c_adapter *adap, u8 dev) 445 { 446 struct i2c_regs *i2c_base = i2c_get_base(adap); 447 u32 tmp; 448 int ret; 449 450 /* 451 * Try to read the first location of the chip. 452 */ 453 ret = __dw_i2c_read(i2c_base, dev, 0, 1, (uchar *)&tmp, 1); 454 if (ret) 455 dw_i2c_init(adap, adap->speed, adap->slaveaddr); 456 457 return ret; 458 } 459 460 U_BOOT_I2C_ADAP_COMPLETE(dw_0, dw_i2c_init, dw_i2c_probe, dw_i2c_read, 461 dw_i2c_write, dw_i2c_set_bus_speed, 462 CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE, 0) 463 464 #if CONFIG_SYS_I2C_BUS_MAX >= 2 465 U_BOOT_I2C_ADAP_COMPLETE(dw_1, dw_i2c_init, dw_i2c_probe, dw_i2c_read, 466 dw_i2c_write, dw_i2c_set_bus_speed, 467 CONFIG_SYS_I2C_SPEED1, CONFIG_SYS_I2C_SLAVE1, 1) 468 #endif 469 470 #if CONFIG_SYS_I2C_BUS_MAX >= 3 471 U_BOOT_I2C_ADAP_COMPLETE(dw_2, dw_i2c_init, dw_i2c_probe, dw_i2c_read, 472 dw_i2c_write, dw_i2c_set_bus_speed, 473 CONFIG_SYS_I2C_SPEED2, CONFIG_SYS_I2C_SLAVE2, 2) 474 #endif 475 476 #if CONFIG_SYS_I2C_BUS_MAX >= 4 477 U_BOOT_I2C_ADAP_COMPLETE(dw_3, dw_i2c_init, dw_i2c_probe, dw_i2c_read, 478 dw_i2c_write, dw_i2c_set_bus_speed, 479 CONFIG_SYS_I2C_SPEED3, CONFIG_SYS_I2C_SLAVE3, 3) 480 #endif 481 482 #else /* CONFIG_DM_I2C */ 483 /* The DM I2C functions */ 484 485 static int designware_i2c_xfer(struct udevice *bus, struct i2c_msg *msg, 486 int nmsgs) 487 { 488 struct dw_i2c *i2c = dev_get_priv(bus); 489 int ret; 490 491 debug("i2c_xfer: %d messages\n", nmsgs); 492 for (; nmsgs > 0; nmsgs--, msg++) { 493 debug("i2c_xfer: chip=0x%x, len=0x%x\n", msg->addr, msg->len); 494 if (msg->flags & I2C_M_RD) { 495 ret = __dw_i2c_read(i2c->regs, msg->addr, 0, 0, 496 msg->buf, msg->len); 497 } else { 498 ret = __dw_i2c_write(i2c->regs, msg->addr, 0, 0, 499 msg->buf, msg->len); 500 } 501 if (ret) { 502 debug("i2c_write: error sending\n"); 503 return -EREMOTEIO; 504 } 505 } 506 507 return 0; 508 } 509 510 static int designware_i2c_set_bus_speed(struct udevice *bus, unsigned int speed) 511 { 512 struct dw_i2c *i2c = dev_get_priv(bus); 513 514 return __dw_i2c_set_bus_speed(i2c->regs, i2c->scl_sda_cfg, speed); 515 } 516 517 static int designware_i2c_probe_chip(struct udevice *bus, uint chip_addr, 518 uint chip_flags) 519 { 520 struct dw_i2c *i2c = dev_get_priv(bus); 521 struct i2c_regs *i2c_base = i2c->regs; 522 u32 tmp; 523 int ret; 524 525 /* Try to read the first location of the chip */ 526 ret = __dw_i2c_read(i2c_base, chip_addr, 0, 1, (uchar *)&tmp, 1); 527 if (ret) 528 __dw_i2c_init(i2c_base, 0, 0); 529 530 return ret; 531 } 532 533 static int designware_i2c_probe(struct udevice *bus) 534 { 535 struct dw_i2c *priv = dev_get_priv(bus); 536 537 if (device_is_on_pci_bus(bus)) { 538 #ifdef CONFIG_DM_PCI 539 /* Save base address from PCI BAR */ 540 priv->regs = (struct i2c_regs *) 541 dm_pci_map_bar(bus, PCI_BASE_ADDRESS_0, PCI_REGION_MEM); 542 #ifdef CONFIG_X86 543 /* Use BayTrail specific timing values */ 544 priv->scl_sda_cfg = &byt_config; 545 #endif 546 #endif 547 } else { 548 priv->regs = (struct i2c_regs *)dev_get_addr_ptr(bus); 549 } 550 551 __dw_i2c_init(priv->regs, 0, 0); 552 553 return 0; 554 } 555 556 static int designware_i2c_bind(struct udevice *dev) 557 { 558 static int num_cards; 559 char name[20]; 560 561 /* Create a unique device name for PCI type devices */ 562 if (device_is_on_pci_bus(dev)) { 563 /* 564 * ToDo: 565 * Setting req_seq in the driver is probably not recommended. 566 * But without a DT alias the number is not configured. And 567 * using this driver is impossible for PCIe I2C devices. 568 * This can be removed, once a better (correct) way for this 569 * is found and implemented. 570 */ 571 dev->req_seq = num_cards; 572 sprintf(name, "i2c_designware#%u", num_cards++); 573 device_set_name(dev, name); 574 } 575 576 return 0; 577 } 578 579 static const struct dm_i2c_ops designware_i2c_ops = { 580 .xfer = designware_i2c_xfer, 581 .probe_chip = designware_i2c_probe_chip, 582 .set_bus_speed = designware_i2c_set_bus_speed, 583 }; 584 585 static const struct udevice_id designware_i2c_ids[] = { 586 { .compatible = "snps,designware-i2c" }, 587 { } 588 }; 589 590 U_BOOT_DRIVER(i2c_designware) = { 591 .name = "i2c_designware", 592 .id = UCLASS_I2C, 593 .of_match = designware_i2c_ids, 594 .bind = designware_i2c_bind, 595 .probe = designware_i2c_probe, 596 .priv_auto_alloc_size = sizeof(struct dw_i2c), 597 .ops = &designware_i2c_ops, 598 }; 599 600 #ifdef CONFIG_X86 601 static struct pci_device_id designware_pci_supported[] = { 602 /* Intel BayTrail has 7 I2C controller located on the PCI bus */ 603 { PCI_VDEVICE(INTEL, 0x0f41) }, 604 { PCI_VDEVICE(INTEL, 0x0f42) }, 605 { PCI_VDEVICE(INTEL, 0x0f43) }, 606 { PCI_VDEVICE(INTEL, 0x0f44) }, 607 { PCI_VDEVICE(INTEL, 0x0f45) }, 608 { PCI_VDEVICE(INTEL, 0x0f46) }, 609 { PCI_VDEVICE(INTEL, 0x0f47) }, 610 {}, 611 }; 612 613 U_BOOT_PCI_DEVICE(i2c_designware, designware_pci_supported); 614 #endif 615 616 #endif /* CONFIG_DM_I2C */ 617