1 /* 2 * ARM Aspeed I2C controller 3 * 4 * Copyright (C) 2016 IBM Corp. 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License 8 * as published by the Free Software Foundation; either version 2 9 * of the License, or (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, see <http://www.gnu.org/licenses/>. 18 * 19 */ 20 21 #include "qemu/osdep.h" 22 #include "hw/sysbus.h" 23 #include "qemu/log.h" 24 #include "hw/i2c/aspeed_i2c.h" 25 26 /* I2C Global Register */ 27 28 #define I2C_CTRL_STATUS 0x00 /* Device Interrupt Status */ 29 #define I2C_CTRL_ASSIGN 0x08 /* Device Interrupt Target 30 Assignment */ 31 32 /* I2C Device (Bus) Register */ 33 34 #define I2CD_FUN_CTRL_REG 0x00 /* I2CD Function Control */ 35 #define I2CD_BUFF_SEL_MASK (0x7 << 20) 36 #define I2CD_BUFF_SEL(x) (x << 20) 37 #define I2CD_M_SDA_LOCK_EN (0x1 << 16) 38 #define I2CD_MULTI_MASTER_DIS (0x1 << 15) 39 #define I2CD_M_SCL_DRIVE_EN (0x1 << 14) 40 #define I2CD_MSB_STS (0x1 << 9) 41 #define I2CD_SDA_DRIVE_1T_EN (0x1 << 8) 42 #define I2CD_M_SDA_DRIVE_1T_EN (0x1 << 7) 43 #define I2CD_M_HIGH_SPEED_EN (0x1 << 6) 44 #define I2CD_DEF_ADDR_EN (0x1 << 5) 45 #define I2CD_DEF_ALERT_EN (0x1 << 4) 46 #define I2CD_DEF_ARP_EN (0x1 << 3) 47 #define I2CD_DEF_GCALL_EN (0x1 << 2) 48 #define I2CD_SLAVE_EN (0x1 << 1) 49 #define I2CD_MASTER_EN (0x1) 50 51 #define I2CD_AC_TIMING_REG1 0x04 /* Clock and AC Timing Control #1 */ 52 #define I2CD_AC_TIMING_REG2 0x08 /* Clock and AC Timing Control #1 */ 53 #define I2CD_INTR_CTRL_REG 0x0c /* I2CD Interrupt Control */ 54 #define I2CD_INTR_STS_REG 0x10 /* I2CD Interrupt Status */ 55 #define I2CD_INTR_SDA_DL_TIMEOUT (0x1 << 14) 56 #define I2CD_INTR_BUS_RECOVER_DONE (0x1 << 13) 57 #define I2CD_INTR_SMBUS_ALERT (0x1 << 12) /* Bus [0-3] only */ 58 #define I2CD_INTR_SMBUS_ARP_ADDR (0x1 << 11) /* Removed */ 59 #define I2CD_INTR_SMBUS_DEV_ALERT_ADDR (0x1 << 10) /* Removed */ 60 #define I2CD_INTR_SMBUS_DEF_ADDR (0x1 << 9) /* Removed */ 61 #define I2CD_INTR_GCALL_ADDR (0x1 << 8) /* Removed */ 62 #define I2CD_INTR_SLAVE_MATCH (0x1 << 7) /* use RX_DONE */ 63 #define I2CD_INTR_SCL_TIMEOUT (0x1 << 6) 64 #define I2CD_INTR_ABNORMAL (0x1 << 5) 65 #define I2CD_INTR_NORMAL_STOP (0x1 << 4) 66 #define I2CD_INTR_ARBIT_LOSS (0x1 << 3) 67 #define I2CD_INTR_RX_DONE (0x1 << 2) 68 #define I2CD_INTR_TX_NAK (0x1 << 1) 69 #define I2CD_INTR_TX_ACK (0x1 << 0) 70 71 #define I2CD_CMD_REG 0x14 /* I2CD Command/Status */ 72 #define I2CD_SDA_OE (0x1 << 28) 73 #define I2CD_SDA_O (0x1 << 27) 74 #define I2CD_SCL_OE (0x1 << 26) 75 #define I2CD_SCL_O (0x1 << 25) 76 #define I2CD_TX_TIMING (0x1 << 24) 77 #define I2CD_TX_STATUS (0x1 << 23) 78 79 #define I2CD_TX_STATE_SHIFT 19 /* Tx State Machine */ 80 #define I2CD_TX_STATE_MASK 0xf 81 #define I2CD_IDLE 0x0 82 #define I2CD_MACTIVE 0x8 83 #define I2CD_MSTART 0x9 84 #define I2CD_MSTARTR 0xa 85 #define I2CD_MSTOP 0xb 86 #define I2CD_MTXD 0xc 87 #define I2CD_MRXACK 0xd 88 #define I2CD_MRXD 0xe 89 #define I2CD_MTXACK 0xf 90 #define I2CD_SWAIT 0x1 91 #define I2CD_SRXD 0x4 92 #define I2CD_STXACK 0x5 93 #define I2CD_STXD 0x6 94 #define I2CD_SRXACK 0x7 95 #define I2CD_RECOVER 0x3 96 97 #define I2CD_SCL_LINE_STS (0x1 << 18) 98 #define I2CD_SDA_LINE_STS (0x1 << 17) 99 #define I2CD_BUS_BUSY_STS (0x1 << 16) 100 #define I2CD_SDA_OE_OUT_DIR (0x1 << 15) 101 #define I2CD_SDA_O_OUT_DIR (0x1 << 14) 102 #define I2CD_SCL_OE_OUT_DIR (0x1 << 13) 103 #define I2CD_SCL_O_OUT_DIR (0x1 << 12) 104 #define I2CD_BUS_RECOVER_CMD_EN (0x1 << 11) 105 #define I2CD_S_ALT_EN (0x1 << 10) 106 #define I2CD_RX_DMA_ENABLE (0x1 << 9) 107 #define I2CD_TX_DMA_ENABLE (0x1 << 8) 108 109 /* Command Bit */ 110 #define I2CD_M_STOP_CMD (0x1 << 5) 111 #define I2CD_M_S_RX_CMD_LAST (0x1 << 4) 112 #define I2CD_M_RX_CMD (0x1 << 3) 113 #define I2CD_S_TX_CMD (0x1 << 2) 114 #define I2CD_M_TX_CMD (0x1 << 1) 115 #define I2CD_M_START_CMD (0x1) 116 117 #define I2CD_DEV_ADDR_REG 0x18 /* Slave Device Address */ 118 #define I2CD_BUF_CTRL_REG 0x1c /* Pool Buffer Control */ 119 #define I2CD_BYTE_BUF_REG 0x20 /* Transmit/Receive Byte Buffer */ 120 #define I2CD_BYTE_BUF_TX_SHIFT 0 121 #define I2CD_BYTE_BUF_TX_MASK 0xff 122 #define I2CD_BYTE_BUF_RX_SHIFT 8 123 #define I2CD_BYTE_BUF_RX_MASK 0xff 124 125 126 static inline bool aspeed_i2c_bus_is_master(AspeedI2CBus *bus) 127 { 128 return bus->ctrl & I2CD_MASTER_EN; 129 } 130 131 static inline bool aspeed_i2c_bus_is_enabled(AspeedI2CBus *bus) 132 { 133 return bus->ctrl & (I2CD_MASTER_EN | I2CD_SLAVE_EN); 134 } 135 136 static inline void aspeed_i2c_bus_raise_interrupt(AspeedI2CBus *bus) 137 { 138 bus->intr_status &= bus->intr_ctrl; 139 if (bus->intr_status) { 140 bus->controller->intr_status |= 1 << bus->id; 141 qemu_irq_raise(bus->controller->irq); 142 } 143 } 144 145 static uint64_t aspeed_i2c_bus_read(void *opaque, hwaddr offset, 146 unsigned size) 147 { 148 AspeedI2CBus *bus = opaque; 149 150 switch (offset) { 151 case I2CD_FUN_CTRL_REG: 152 return bus->ctrl; 153 case I2CD_AC_TIMING_REG1: 154 return bus->timing[0]; 155 case I2CD_AC_TIMING_REG2: 156 return bus->timing[1]; 157 case I2CD_INTR_CTRL_REG: 158 return bus->intr_ctrl; 159 case I2CD_INTR_STS_REG: 160 return bus->intr_status; 161 case I2CD_BYTE_BUF_REG: 162 return bus->buf; 163 case I2CD_CMD_REG: 164 return bus->cmd | (i2c_bus_busy(bus->bus) << 16); 165 default: 166 qemu_log_mask(LOG_GUEST_ERROR, 167 "%s: Bad offset 0x%" HWADDR_PRIx "\n", __func__, offset); 168 return -1; 169 } 170 } 171 172 static void aspeed_i2c_set_state(AspeedI2CBus *bus, uint8_t state) 173 { 174 bus->cmd &= ~(I2CD_TX_STATE_MASK << I2CD_TX_STATE_SHIFT); 175 bus->cmd |= (state & I2CD_TX_STATE_MASK) << I2CD_TX_STATE_SHIFT; 176 } 177 178 static uint8_t aspeed_i2c_get_state(AspeedI2CBus *bus) 179 { 180 return (bus->cmd >> I2CD_TX_STATE_SHIFT) & I2CD_TX_STATE_MASK; 181 } 182 183 /* 184 * The state machine needs some refinement. It is only used to track 185 * invalid STOP commands for the moment. 186 */ 187 static void aspeed_i2c_bus_handle_cmd(AspeedI2CBus *bus, uint64_t value) 188 { 189 bus->cmd &= ~0xFFFF; 190 bus->cmd |= value & 0xFFFF; 191 bus->intr_status = 0; 192 193 if (bus->cmd & I2CD_M_START_CMD) { 194 uint8_t state = aspeed_i2c_get_state(bus) & I2CD_MACTIVE ? 195 I2CD_MSTARTR : I2CD_MSTART; 196 197 aspeed_i2c_set_state(bus, state); 198 199 if (i2c_start_transfer(bus->bus, extract32(bus->buf, 1, 7), 200 extract32(bus->buf, 0, 1))) { 201 bus->intr_status |= I2CD_INTR_TX_NAK; 202 } else { 203 bus->intr_status |= I2CD_INTR_TX_ACK; 204 } 205 206 /* START command is also a TX command, as the slave address is 207 * sent on the bus */ 208 bus->cmd &= ~(I2CD_M_START_CMD | I2CD_M_TX_CMD); 209 210 /* No slave found */ 211 if (!i2c_bus_busy(bus->bus)) { 212 return; 213 } 214 aspeed_i2c_set_state(bus, I2CD_MACTIVE); 215 } 216 217 if (bus->cmd & I2CD_M_TX_CMD) { 218 aspeed_i2c_set_state(bus, I2CD_MTXD); 219 if (i2c_send(bus->bus, bus->buf)) { 220 bus->intr_status |= (I2CD_INTR_TX_NAK); 221 i2c_end_transfer(bus->bus); 222 } else { 223 bus->intr_status |= I2CD_INTR_TX_ACK; 224 } 225 bus->cmd &= ~I2CD_M_TX_CMD; 226 aspeed_i2c_set_state(bus, I2CD_MACTIVE); 227 } 228 229 if (bus->cmd & (I2CD_M_RX_CMD | I2CD_M_S_RX_CMD_LAST)) { 230 int ret; 231 232 aspeed_i2c_set_state(bus, I2CD_MRXD); 233 ret = i2c_recv(bus->bus); 234 if (ret < 0) { 235 qemu_log_mask(LOG_GUEST_ERROR, "%s: read failed\n", __func__); 236 ret = 0xff; 237 } else { 238 bus->intr_status |= I2CD_INTR_RX_DONE; 239 } 240 bus->buf = (ret & I2CD_BYTE_BUF_RX_MASK) << I2CD_BYTE_BUF_RX_SHIFT; 241 if (bus->cmd & I2CD_M_S_RX_CMD_LAST) { 242 i2c_nack(bus->bus); 243 } 244 bus->cmd &= ~(I2CD_M_RX_CMD | I2CD_M_S_RX_CMD_LAST); 245 aspeed_i2c_set_state(bus, I2CD_MACTIVE); 246 } 247 248 if (bus->cmd & I2CD_M_STOP_CMD) { 249 if (!(aspeed_i2c_get_state(bus) & I2CD_MACTIVE)) { 250 qemu_log_mask(LOG_GUEST_ERROR, "%s: abnormal stop\n", __func__); 251 bus->intr_status |= I2CD_INTR_ABNORMAL; 252 } else { 253 aspeed_i2c_set_state(bus, I2CD_MSTOP); 254 i2c_end_transfer(bus->bus); 255 bus->intr_status |= I2CD_INTR_NORMAL_STOP; 256 } 257 bus->cmd &= ~I2CD_M_STOP_CMD; 258 aspeed_i2c_set_state(bus, I2CD_IDLE); 259 } 260 } 261 262 static void aspeed_i2c_bus_write(void *opaque, hwaddr offset, 263 uint64_t value, unsigned size) 264 { 265 AspeedI2CBus *bus = opaque; 266 267 switch (offset) { 268 case I2CD_FUN_CTRL_REG: 269 if (value & I2CD_SLAVE_EN) { 270 qemu_log_mask(LOG_UNIMP, "%s: slave mode not implemented\n", 271 __func__); 272 break; 273 } 274 bus->ctrl = value & 0x0071C3FF; 275 break; 276 case I2CD_AC_TIMING_REG1: 277 bus->timing[0] = value & 0xFFFFF0F; 278 break; 279 case I2CD_AC_TIMING_REG2: 280 bus->timing[1] = value & 0x7; 281 break; 282 case I2CD_INTR_CTRL_REG: 283 bus->intr_ctrl = value & 0x7FFF; 284 break; 285 case I2CD_INTR_STS_REG: 286 bus->intr_status &= ~(value & 0x7FFF); 287 bus->controller->intr_status &= ~(1 << bus->id); 288 qemu_irq_lower(bus->controller->irq); 289 break; 290 case I2CD_DEV_ADDR_REG: 291 qemu_log_mask(LOG_UNIMP, "%s: slave mode not implemented\n", 292 __func__); 293 break; 294 case I2CD_BYTE_BUF_REG: 295 bus->buf = (value & I2CD_BYTE_BUF_TX_MASK) << I2CD_BYTE_BUF_TX_SHIFT; 296 break; 297 case I2CD_CMD_REG: 298 if (!aspeed_i2c_bus_is_enabled(bus)) { 299 break; 300 } 301 302 if (!aspeed_i2c_bus_is_master(bus)) { 303 qemu_log_mask(LOG_UNIMP, "%s: slave mode not implemented\n", 304 __func__); 305 break; 306 } 307 308 aspeed_i2c_bus_handle_cmd(bus, value); 309 aspeed_i2c_bus_raise_interrupt(bus); 310 break; 311 312 default: 313 qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset 0x%" HWADDR_PRIx "\n", 314 __func__, offset); 315 } 316 } 317 318 static uint64_t aspeed_i2c_ctrl_read(void *opaque, hwaddr offset, 319 unsigned size) 320 { 321 AspeedI2CState *s = opaque; 322 323 switch (offset) { 324 case I2C_CTRL_STATUS: 325 return s->intr_status; 326 default: 327 qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset 0x%" HWADDR_PRIx "\n", 328 __func__, offset); 329 break; 330 } 331 332 return -1; 333 } 334 335 static void aspeed_i2c_ctrl_write(void *opaque, hwaddr offset, 336 uint64_t value, unsigned size) 337 { 338 switch (offset) { 339 case I2C_CTRL_STATUS: 340 default: 341 qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset 0x%" HWADDR_PRIx "\n", 342 __func__, offset); 343 break; 344 } 345 } 346 347 static const MemoryRegionOps aspeed_i2c_bus_ops = { 348 .read = aspeed_i2c_bus_read, 349 .write = aspeed_i2c_bus_write, 350 .endianness = DEVICE_LITTLE_ENDIAN, 351 }; 352 353 static const MemoryRegionOps aspeed_i2c_ctrl_ops = { 354 .read = aspeed_i2c_ctrl_read, 355 .write = aspeed_i2c_ctrl_write, 356 .endianness = DEVICE_LITTLE_ENDIAN, 357 }; 358 359 static const VMStateDescription aspeed_i2c_bus_vmstate = { 360 .name = TYPE_ASPEED_I2C, 361 .version_id = 1, 362 .minimum_version_id = 1, 363 .fields = (VMStateField[]) { 364 VMSTATE_UINT8(id, AspeedI2CBus), 365 VMSTATE_UINT32(ctrl, AspeedI2CBus), 366 VMSTATE_UINT32_ARRAY(timing, AspeedI2CBus, 2), 367 VMSTATE_UINT32(intr_ctrl, AspeedI2CBus), 368 VMSTATE_UINT32(intr_status, AspeedI2CBus), 369 VMSTATE_UINT32(cmd, AspeedI2CBus), 370 VMSTATE_UINT32(buf, AspeedI2CBus), 371 VMSTATE_END_OF_LIST() 372 } 373 }; 374 375 static const VMStateDescription aspeed_i2c_vmstate = { 376 .name = TYPE_ASPEED_I2C, 377 .version_id = 1, 378 .minimum_version_id = 1, 379 .fields = (VMStateField[]) { 380 VMSTATE_UINT32(intr_status, AspeedI2CState), 381 VMSTATE_STRUCT_ARRAY(busses, AspeedI2CState, 382 ASPEED_I2C_NR_BUSSES, 1, aspeed_i2c_bus_vmstate, 383 AspeedI2CBus), 384 VMSTATE_END_OF_LIST() 385 } 386 }; 387 388 static void aspeed_i2c_reset(DeviceState *dev) 389 { 390 int i; 391 AspeedI2CState *s = ASPEED_I2C(dev); 392 393 s->intr_status = 0; 394 395 for (i = 0; i < ASPEED_I2C_NR_BUSSES; i++) { 396 s->busses[i].intr_ctrl = 0; 397 s->busses[i].intr_status = 0; 398 s->busses[i].cmd = 0; 399 s->busses[i].buf = 0; 400 i2c_end_transfer(s->busses[i].bus); 401 } 402 } 403 404 /* 405 * Address Definitions 406 * 407 * 0x000 ... 0x03F: Global Register 408 * 0x040 ... 0x07F: Device 1 409 * 0x080 ... 0x0BF: Device 2 410 * 0x0C0 ... 0x0FF: Device 3 411 * 0x100 ... 0x13F: Device 4 412 * 0x140 ... 0x17F: Device 5 413 * 0x180 ... 0x1BF: Device 6 414 * 0x1C0 ... 0x1FF: Device 7 415 * 0x200 ... 0x2FF: Buffer Pool (unused in linux driver) 416 * 0x300 ... 0x33F: Device 8 417 * 0x340 ... 0x37F: Device 9 418 * 0x380 ... 0x3BF: Device 10 419 * 0x3C0 ... 0x3FF: Device 11 420 * 0x400 ... 0x43F: Device 12 421 * 0x440 ... 0x47F: Device 13 422 * 0x480 ... 0x4BF: Device 14 423 * 0x800 ... 0xFFF: Buffer Pool (unused in linux driver) 424 */ 425 static void aspeed_i2c_realize(DeviceState *dev, Error **errp) 426 { 427 int i; 428 SysBusDevice *sbd = SYS_BUS_DEVICE(dev); 429 AspeedI2CState *s = ASPEED_I2C(dev); 430 431 sysbus_init_irq(sbd, &s->irq); 432 memory_region_init_io(&s->iomem, OBJECT(s), &aspeed_i2c_ctrl_ops, s, 433 "aspeed.i2c", 0x1000); 434 sysbus_init_mmio(sbd, &s->iomem); 435 436 for (i = 0; i < ASPEED_I2C_NR_BUSSES; i++) { 437 char name[16]; 438 int offset = i < 7 ? 1 : 5; 439 snprintf(name, sizeof(name), "aspeed.i2c.%d", i); 440 s->busses[i].controller = s; 441 s->busses[i].id = i; 442 s->busses[i].bus = i2c_init_bus(dev, name); 443 memory_region_init_io(&s->busses[i].mr, OBJECT(dev), 444 &aspeed_i2c_bus_ops, &s->busses[i], name, 0x40); 445 memory_region_add_subregion(&s->iomem, 0x40 * (i + offset), 446 &s->busses[i].mr); 447 } 448 } 449 450 static void aspeed_i2c_class_init(ObjectClass *klass, void *data) 451 { 452 DeviceClass *dc = DEVICE_CLASS(klass); 453 454 dc->vmsd = &aspeed_i2c_vmstate; 455 dc->reset = aspeed_i2c_reset; 456 dc->realize = aspeed_i2c_realize; 457 dc->desc = "Aspeed I2C Controller"; 458 } 459 460 static const TypeInfo aspeed_i2c_info = { 461 .name = TYPE_ASPEED_I2C, 462 .parent = TYPE_SYS_BUS_DEVICE, 463 .instance_size = sizeof(AspeedI2CState), 464 .class_init = aspeed_i2c_class_init, 465 }; 466 467 static void aspeed_i2c_register_types(void) 468 { 469 type_register_static(&aspeed_i2c_info); 470 } 471 472 type_init(aspeed_i2c_register_types) 473 474 475 I2CBus *aspeed_i2c_get_bus(DeviceState *dev, int busnr) 476 { 477 AspeedI2CState *s = ASPEED_I2C(dev); 478 I2CBus *bus = NULL; 479 480 if (busnr >= 0 && busnr < ASPEED_I2C_NR_BUSSES) { 481 bus = s->busses[busnr].bus; 482 } 483 484 return bus; 485 } 486