1 /* 2 * QEMU 16550A UART emulation 3 * 4 * Copyright (c) 2003-2004 Fabrice Bellard 5 * Copyright (c) 2008 Citrix Systems, Inc. 6 * 7 * Permission is hereby granted, free of charge, to any person obtaining a copy 8 * of this software and associated documentation files (the "Software"), to deal 9 * in the Software without restriction, including without limitation the rights 10 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 11 * copies of the Software, and to permit persons to whom the Software is 12 * furnished to do so, subject to the following conditions: 13 * 14 * The above copyright notice and this permission notice shall be included in 15 * all copies or substantial portions of the Software. 16 * 17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 18 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 20 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 21 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 22 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 23 * THE SOFTWARE. 24 */ 25 26 #include "hw/char/serial.h" 27 #include "sysemu/char.h" 28 #include "qemu/timer.h" 29 #include "exec/address-spaces.h" 30 #include "qemu/error-report.h" 31 32 //#define DEBUG_SERIAL 33 34 #define UART_LCR_DLAB 0x80 /* Divisor latch access bit */ 35 36 #define UART_IER_MSI 0x08 /* Enable Modem status interrupt */ 37 #define UART_IER_RLSI 0x04 /* Enable receiver line status interrupt */ 38 #define UART_IER_THRI 0x02 /* Enable Transmitter holding register int. */ 39 #define UART_IER_RDI 0x01 /* Enable receiver data interrupt */ 40 41 #define UART_IIR_NO_INT 0x01 /* No interrupts pending */ 42 #define UART_IIR_ID 0x06 /* Mask for the interrupt ID */ 43 44 #define UART_IIR_MSI 0x00 /* Modem status interrupt */ 45 #define UART_IIR_THRI 0x02 /* Transmitter holding register empty */ 46 #define UART_IIR_RDI 0x04 /* Receiver data interrupt */ 47 #define UART_IIR_RLSI 0x06 /* Receiver line status interrupt */ 48 #define UART_IIR_CTI 0x0C /* Character Timeout Indication */ 49 50 #define UART_IIR_FENF 0x80 /* Fifo enabled, but not functionning */ 51 #define UART_IIR_FE 0xC0 /* Fifo enabled */ 52 53 /* 54 * These are the definitions for the Modem Control Register 55 */ 56 #define UART_MCR_LOOP 0x10 /* Enable loopback test mode */ 57 #define UART_MCR_OUT2 0x08 /* Out2 complement */ 58 #define UART_MCR_OUT1 0x04 /* Out1 complement */ 59 #define UART_MCR_RTS 0x02 /* RTS complement */ 60 #define UART_MCR_DTR 0x01 /* DTR complement */ 61 62 /* 63 * These are the definitions for the Modem Status Register 64 */ 65 #define UART_MSR_DCD 0x80 /* Data Carrier Detect */ 66 #define UART_MSR_RI 0x40 /* Ring Indicator */ 67 #define UART_MSR_DSR 0x20 /* Data Set Ready */ 68 #define UART_MSR_CTS 0x10 /* Clear to Send */ 69 #define UART_MSR_DDCD 0x08 /* Delta DCD */ 70 #define UART_MSR_TERI 0x04 /* Trailing edge ring indicator */ 71 #define UART_MSR_DDSR 0x02 /* Delta DSR */ 72 #define UART_MSR_DCTS 0x01 /* Delta CTS */ 73 #define UART_MSR_ANY_DELTA 0x0F /* Any of the delta bits! */ 74 75 #define UART_LSR_TEMT 0x40 /* Transmitter empty */ 76 #define UART_LSR_THRE 0x20 /* Transmit-hold-register empty */ 77 #define UART_LSR_BI 0x10 /* Break interrupt indicator */ 78 #define UART_LSR_FE 0x08 /* Frame error indicator */ 79 #define UART_LSR_PE 0x04 /* Parity error indicator */ 80 #define UART_LSR_OE 0x02 /* Overrun error indicator */ 81 #define UART_LSR_DR 0x01 /* Receiver data ready */ 82 #define UART_LSR_INT_ANY 0x1E /* Any of the lsr-interrupt-triggering status bits */ 83 84 /* Interrupt trigger levels. The byte-counts are for 16550A - in newer UARTs the byte-count for each ITL is higher. */ 85 86 #define UART_FCR_ITL_1 0x00 /* 1 byte ITL */ 87 #define UART_FCR_ITL_2 0x40 /* 4 bytes ITL */ 88 #define UART_FCR_ITL_3 0x80 /* 8 bytes ITL */ 89 #define UART_FCR_ITL_4 0xC0 /* 14 bytes ITL */ 90 91 #define UART_FCR_DMS 0x08 /* DMA Mode Select */ 92 #define UART_FCR_XFR 0x04 /* XMIT Fifo Reset */ 93 #define UART_FCR_RFR 0x02 /* RCVR Fifo Reset */ 94 #define UART_FCR_FE 0x01 /* FIFO Enable */ 95 96 #define MAX_XMIT_RETRY 4 97 98 #ifdef DEBUG_SERIAL 99 #define DPRINTF(fmt, ...) \ 100 do { fprintf(stderr, "serial: " fmt , ## __VA_ARGS__); } while (0) 101 #else 102 #define DPRINTF(fmt, ...) \ 103 do {} while (0) 104 #endif 105 106 static void serial_receive1(void *opaque, const uint8_t *buf, int size); 107 108 static inline void recv_fifo_put(SerialState *s, uint8_t chr) 109 { 110 /* Receive overruns do not overwrite FIFO contents. */ 111 if (!fifo8_is_full(&s->recv_fifo)) { 112 fifo8_push(&s->recv_fifo, chr); 113 } else { 114 s->lsr |= UART_LSR_OE; 115 } 116 } 117 118 static void serial_update_irq(SerialState *s) 119 { 120 uint8_t tmp_iir = UART_IIR_NO_INT; 121 122 if ((s->ier & UART_IER_RLSI) && (s->lsr & UART_LSR_INT_ANY)) { 123 tmp_iir = UART_IIR_RLSI; 124 } else if ((s->ier & UART_IER_RDI) && s->timeout_ipending) { 125 /* Note that(s->ier & UART_IER_RDI) can mask this interrupt, 126 * this is not in the specification but is observed on existing 127 * hardware. */ 128 tmp_iir = UART_IIR_CTI; 129 } else if ((s->ier & UART_IER_RDI) && (s->lsr & UART_LSR_DR) && 130 (!(s->fcr & UART_FCR_FE) || 131 s->recv_fifo.num >= s->recv_fifo_itl)) { 132 tmp_iir = UART_IIR_RDI; 133 } else if ((s->ier & UART_IER_THRI) && s->thr_ipending) { 134 tmp_iir = UART_IIR_THRI; 135 } else if ((s->ier & UART_IER_MSI) && (s->msr & UART_MSR_ANY_DELTA)) { 136 tmp_iir = UART_IIR_MSI; 137 } 138 139 s->iir = tmp_iir | (s->iir & 0xF0); 140 141 if (tmp_iir != UART_IIR_NO_INT) { 142 qemu_irq_raise(s->irq); 143 } else { 144 qemu_irq_lower(s->irq); 145 } 146 } 147 148 static void serial_update_parameters(SerialState *s) 149 { 150 int speed, parity, data_bits, stop_bits, frame_size; 151 QEMUSerialSetParams ssp; 152 153 if (s->divider == 0) 154 return; 155 156 /* Start bit. */ 157 frame_size = 1; 158 if (s->lcr & 0x08) { 159 /* Parity bit. */ 160 frame_size++; 161 if (s->lcr & 0x10) 162 parity = 'E'; 163 else 164 parity = 'O'; 165 } else { 166 parity = 'N'; 167 } 168 if (s->lcr & 0x04) 169 stop_bits = 2; 170 else 171 stop_bits = 1; 172 173 data_bits = (s->lcr & 0x03) + 5; 174 frame_size += data_bits + stop_bits; 175 speed = s->baudbase / s->divider; 176 ssp.speed = speed; 177 ssp.parity = parity; 178 ssp.data_bits = data_bits; 179 ssp.stop_bits = stop_bits; 180 s->char_transmit_time = (get_ticks_per_sec() / speed) * frame_size; 181 qemu_chr_fe_ioctl(s->chr, CHR_IOCTL_SERIAL_SET_PARAMS, &ssp); 182 183 DPRINTF("speed=%d parity=%c data=%d stop=%d\n", 184 speed, parity, data_bits, stop_bits); 185 } 186 187 static void serial_update_msl(SerialState *s) 188 { 189 uint8_t omsr; 190 int flags; 191 192 timer_del(s->modem_status_poll); 193 194 if (qemu_chr_fe_ioctl(s->chr,CHR_IOCTL_SERIAL_GET_TIOCM, &flags) == -ENOTSUP) { 195 s->poll_msl = -1; 196 return; 197 } 198 199 omsr = s->msr; 200 201 s->msr = (flags & CHR_TIOCM_CTS) ? s->msr | UART_MSR_CTS : s->msr & ~UART_MSR_CTS; 202 s->msr = (flags & CHR_TIOCM_DSR) ? s->msr | UART_MSR_DSR : s->msr & ~UART_MSR_DSR; 203 s->msr = (flags & CHR_TIOCM_CAR) ? s->msr | UART_MSR_DCD : s->msr & ~UART_MSR_DCD; 204 s->msr = (flags & CHR_TIOCM_RI) ? s->msr | UART_MSR_RI : s->msr & ~UART_MSR_RI; 205 206 if (s->msr != omsr) { 207 /* Set delta bits */ 208 s->msr = s->msr | ((s->msr >> 4) ^ (omsr >> 4)); 209 /* UART_MSR_TERI only if change was from 1 -> 0 */ 210 if ((s->msr & UART_MSR_TERI) && !(omsr & UART_MSR_RI)) 211 s->msr &= ~UART_MSR_TERI; 212 serial_update_irq(s); 213 } 214 215 /* The real 16550A apparently has a 250ns response latency to line status changes. 216 We'll be lazy and poll only every 10ms, and only poll it at all if MSI interrupts are turned on */ 217 218 if (s->poll_msl) 219 timer_mod(s->modem_status_poll, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + get_ticks_per_sec() / 100); 220 } 221 222 static gboolean serial_xmit(GIOChannel *chan, GIOCondition cond, void *opaque) 223 { 224 SerialState *s = opaque; 225 226 if (s->tsr_retry <= 0) { 227 if (s->fcr & UART_FCR_FE) { 228 if (fifo8_is_empty(&s->xmit_fifo)) { 229 return FALSE; 230 } 231 s->tsr = fifo8_pop(&s->xmit_fifo); 232 if (!s->xmit_fifo.num) { 233 s->lsr |= UART_LSR_THRE; 234 } 235 } else if ((s->lsr & UART_LSR_THRE)) { 236 return FALSE; 237 } else { 238 s->tsr = s->thr; 239 s->lsr |= UART_LSR_THRE; 240 s->lsr &= ~UART_LSR_TEMT; 241 } 242 } 243 244 if (s->mcr & UART_MCR_LOOP) { 245 /* in loopback mode, say that we just received a char */ 246 serial_receive1(s, &s->tsr, 1); 247 } else if (qemu_chr_fe_write(s->chr, &s->tsr, 1) != 1) { 248 if (s->tsr_retry >= 0 && s->tsr_retry < MAX_XMIT_RETRY && 249 qemu_chr_fe_add_watch(s->chr, G_IO_OUT|G_IO_HUP, serial_xmit, s) > 0) { 250 s->tsr_retry++; 251 return FALSE; 252 } 253 s->tsr_retry = 0; 254 } else { 255 s->tsr_retry = 0; 256 } 257 258 s->last_xmit_ts = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL); 259 260 if (s->lsr & UART_LSR_THRE) { 261 s->lsr |= UART_LSR_TEMT; 262 s->thr_ipending = 1; 263 serial_update_irq(s); 264 } 265 266 return FALSE; 267 } 268 269 270 static void serial_ioport_write(void *opaque, hwaddr addr, uint64_t val, 271 unsigned size) 272 { 273 SerialState *s = opaque; 274 275 addr &= 7; 276 DPRINTF("write addr=0x%" HWADDR_PRIx " val=0x%" PRIx64 "\n", addr, val); 277 switch(addr) { 278 default: 279 case 0: 280 if (s->lcr & UART_LCR_DLAB) { 281 s->divider = (s->divider & 0xff00) | val; 282 serial_update_parameters(s); 283 } else { 284 s->thr = (uint8_t) val; 285 if(s->fcr & UART_FCR_FE) { 286 /* xmit overruns overwrite data, so make space if needed */ 287 if (fifo8_is_full(&s->xmit_fifo)) { 288 fifo8_pop(&s->xmit_fifo); 289 } 290 fifo8_push(&s->xmit_fifo, s->thr); 291 s->lsr &= ~UART_LSR_TEMT; 292 } 293 s->thr_ipending = 0; 294 s->lsr &= ~UART_LSR_THRE; 295 serial_update_irq(s); 296 serial_xmit(NULL, G_IO_OUT, s); 297 } 298 break; 299 case 1: 300 if (s->lcr & UART_LCR_DLAB) { 301 s->divider = (s->divider & 0x00ff) | (val << 8); 302 serial_update_parameters(s); 303 } else { 304 s->ier = val & 0x0f; 305 /* If the backend device is a real serial port, turn polling of the modem 306 status lines on physical port on or off depending on UART_IER_MSI state */ 307 if (s->poll_msl >= 0) { 308 if (s->ier & UART_IER_MSI) { 309 s->poll_msl = 1; 310 serial_update_msl(s); 311 } else { 312 timer_del(s->modem_status_poll); 313 s->poll_msl = 0; 314 } 315 } 316 if (s->lsr & UART_LSR_THRE) { 317 s->thr_ipending = 1; 318 serial_update_irq(s); 319 } 320 } 321 break; 322 case 2: 323 val = val & 0xFF; 324 325 if (s->fcr == val) 326 break; 327 328 /* Did the enable/disable flag change? If so, make sure FIFOs get flushed */ 329 if ((val ^ s->fcr) & UART_FCR_FE) 330 val |= UART_FCR_XFR | UART_FCR_RFR; 331 332 /* FIFO clear */ 333 334 if (val & UART_FCR_RFR) { 335 timer_del(s->fifo_timeout_timer); 336 s->timeout_ipending=0; 337 fifo8_reset(&s->recv_fifo); 338 } 339 340 if (val & UART_FCR_XFR) { 341 fifo8_reset(&s->xmit_fifo); 342 } 343 344 if (val & UART_FCR_FE) { 345 s->iir |= UART_IIR_FE; 346 /* Set recv_fifo trigger Level */ 347 switch (val & 0xC0) { 348 case UART_FCR_ITL_1: 349 s->recv_fifo_itl = 1; 350 break; 351 case UART_FCR_ITL_2: 352 s->recv_fifo_itl = 4; 353 break; 354 case UART_FCR_ITL_3: 355 s->recv_fifo_itl = 8; 356 break; 357 case UART_FCR_ITL_4: 358 s->recv_fifo_itl = 14; 359 break; 360 } 361 } else 362 s->iir &= ~UART_IIR_FE; 363 364 /* Set fcr - or at least the bits in it that are supposed to "stick" */ 365 s->fcr = val & 0xC9; 366 serial_update_irq(s); 367 break; 368 case 3: 369 { 370 int break_enable; 371 s->lcr = val; 372 serial_update_parameters(s); 373 break_enable = (val >> 6) & 1; 374 if (break_enable != s->last_break_enable) { 375 s->last_break_enable = break_enable; 376 qemu_chr_fe_ioctl(s->chr, CHR_IOCTL_SERIAL_SET_BREAK, 377 &break_enable); 378 } 379 } 380 break; 381 case 4: 382 { 383 int flags; 384 int old_mcr = s->mcr; 385 s->mcr = val & 0x1f; 386 if (val & UART_MCR_LOOP) 387 break; 388 389 if (s->poll_msl >= 0 && old_mcr != s->mcr) { 390 391 qemu_chr_fe_ioctl(s->chr,CHR_IOCTL_SERIAL_GET_TIOCM, &flags); 392 393 flags &= ~(CHR_TIOCM_RTS | CHR_TIOCM_DTR); 394 395 if (val & UART_MCR_RTS) 396 flags |= CHR_TIOCM_RTS; 397 if (val & UART_MCR_DTR) 398 flags |= CHR_TIOCM_DTR; 399 400 qemu_chr_fe_ioctl(s->chr,CHR_IOCTL_SERIAL_SET_TIOCM, &flags); 401 /* Update the modem status after a one-character-send wait-time, since there may be a response 402 from the device/computer at the other end of the serial line */ 403 timer_mod(s->modem_status_poll, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + s->char_transmit_time); 404 } 405 } 406 break; 407 case 5: 408 break; 409 case 6: 410 break; 411 case 7: 412 s->scr = val; 413 break; 414 } 415 } 416 417 static uint64_t serial_ioport_read(void *opaque, hwaddr addr, unsigned size) 418 { 419 SerialState *s = opaque; 420 uint32_t ret; 421 422 addr &= 7; 423 switch(addr) { 424 default: 425 case 0: 426 if (s->lcr & UART_LCR_DLAB) { 427 ret = s->divider & 0xff; 428 } else { 429 if(s->fcr & UART_FCR_FE) { 430 ret = fifo8_is_empty(&s->recv_fifo) ? 431 0 : fifo8_pop(&s->recv_fifo); 432 if (s->recv_fifo.num == 0) { 433 s->lsr &= ~(UART_LSR_DR | UART_LSR_BI); 434 } else { 435 timer_mod(s->fifo_timeout_timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + s->char_transmit_time * 4); 436 } 437 s->timeout_ipending = 0; 438 } else { 439 ret = s->rbr; 440 s->lsr &= ~(UART_LSR_DR | UART_LSR_BI); 441 } 442 serial_update_irq(s); 443 if (!(s->mcr & UART_MCR_LOOP)) { 444 /* in loopback mode, don't receive any data */ 445 qemu_chr_accept_input(s->chr); 446 } 447 } 448 break; 449 case 1: 450 if (s->lcr & UART_LCR_DLAB) { 451 ret = (s->divider >> 8) & 0xff; 452 } else { 453 ret = s->ier; 454 } 455 break; 456 case 2: 457 ret = s->iir; 458 if ((ret & UART_IIR_ID) == UART_IIR_THRI) { 459 s->thr_ipending = 0; 460 serial_update_irq(s); 461 } 462 break; 463 case 3: 464 ret = s->lcr; 465 break; 466 case 4: 467 ret = s->mcr; 468 break; 469 case 5: 470 ret = s->lsr; 471 /* Clear break and overrun interrupts */ 472 if (s->lsr & (UART_LSR_BI|UART_LSR_OE)) { 473 s->lsr &= ~(UART_LSR_BI|UART_LSR_OE); 474 serial_update_irq(s); 475 } 476 break; 477 case 6: 478 if (s->mcr & UART_MCR_LOOP) { 479 /* in loopback, the modem output pins are connected to the 480 inputs */ 481 ret = (s->mcr & 0x0c) << 4; 482 ret |= (s->mcr & 0x02) << 3; 483 ret |= (s->mcr & 0x01) << 5; 484 } else { 485 if (s->poll_msl >= 0) 486 serial_update_msl(s); 487 ret = s->msr; 488 /* Clear delta bits & msr int after read, if they were set */ 489 if (s->msr & UART_MSR_ANY_DELTA) { 490 s->msr &= 0xF0; 491 serial_update_irq(s); 492 } 493 } 494 break; 495 case 7: 496 ret = s->scr; 497 break; 498 } 499 DPRINTF("read addr=0x%" HWADDR_PRIx " val=0x%02x\n", addr, ret); 500 return ret; 501 } 502 503 static int serial_can_receive(SerialState *s) 504 { 505 if(s->fcr & UART_FCR_FE) { 506 if (s->recv_fifo.num < UART_FIFO_LENGTH) { 507 /* 508 * Advertise (fifo.itl - fifo.count) bytes when count < ITL, and 1 509 * if above. If UART_FIFO_LENGTH - fifo.count is advertised the 510 * effect will be to almost always fill the fifo completely before 511 * the guest has a chance to respond, effectively overriding the ITL 512 * that the guest has set. 513 */ 514 return (s->recv_fifo.num <= s->recv_fifo_itl) ? 515 s->recv_fifo_itl - s->recv_fifo.num : 1; 516 } else { 517 return 0; 518 } 519 } else { 520 return !(s->lsr & UART_LSR_DR); 521 } 522 } 523 524 static void serial_receive_break(SerialState *s) 525 { 526 s->rbr = 0; 527 /* When the LSR_DR is set a null byte is pushed into the fifo */ 528 recv_fifo_put(s, '\0'); 529 s->lsr |= UART_LSR_BI | UART_LSR_DR; 530 serial_update_irq(s); 531 } 532 533 /* There's data in recv_fifo and s->rbr has not been read for 4 char transmit times */ 534 static void fifo_timeout_int (void *opaque) { 535 SerialState *s = opaque; 536 if (s->recv_fifo.num) { 537 s->timeout_ipending = 1; 538 serial_update_irq(s); 539 } 540 } 541 542 static int serial_can_receive1(void *opaque) 543 { 544 SerialState *s = opaque; 545 return serial_can_receive(s); 546 } 547 548 static void serial_receive1(void *opaque, const uint8_t *buf, int size) 549 { 550 SerialState *s = opaque; 551 552 if (s->wakeup) { 553 qemu_system_wakeup_request(QEMU_WAKEUP_REASON_OTHER); 554 } 555 if(s->fcr & UART_FCR_FE) { 556 int i; 557 for (i = 0; i < size; i++) { 558 recv_fifo_put(s, buf[i]); 559 } 560 s->lsr |= UART_LSR_DR; 561 /* call the timeout receive callback in 4 char transmit time */ 562 timer_mod(s->fifo_timeout_timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + s->char_transmit_time * 4); 563 } else { 564 if (s->lsr & UART_LSR_DR) 565 s->lsr |= UART_LSR_OE; 566 s->rbr = buf[0]; 567 s->lsr |= UART_LSR_DR; 568 } 569 serial_update_irq(s); 570 } 571 572 static void serial_event(void *opaque, int event) 573 { 574 SerialState *s = opaque; 575 DPRINTF("event %x\n", event); 576 if (event == CHR_EVENT_BREAK) 577 serial_receive_break(s); 578 } 579 580 static void serial_pre_save(void *opaque) 581 { 582 SerialState *s = opaque; 583 s->fcr_vmstate = s->fcr; 584 } 585 586 static int serial_post_load(void *opaque, int version_id) 587 { 588 SerialState *s = opaque; 589 590 if (version_id < 3) { 591 s->fcr_vmstate = 0; 592 } 593 /* Initialize fcr via setter to perform essential side-effects */ 594 serial_ioport_write(s, 0x02, s->fcr_vmstate, 1); 595 serial_update_parameters(s); 596 return 0; 597 } 598 599 const VMStateDescription vmstate_serial = { 600 .name = "serial", 601 .version_id = 3, 602 .minimum_version_id = 2, 603 .pre_save = serial_pre_save, 604 .post_load = serial_post_load, 605 .fields = (VMStateField[]) { 606 VMSTATE_UINT16_V(divider, SerialState, 2), 607 VMSTATE_UINT8(rbr, SerialState), 608 VMSTATE_UINT8(ier, SerialState), 609 VMSTATE_UINT8(iir, SerialState), 610 VMSTATE_UINT8(lcr, SerialState), 611 VMSTATE_UINT8(mcr, SerialState), 612 VMSTATE_UINT8(lsr, SerialState), 613 VMSTATE_UINT8(msr, SerialState), 614 VMSTATE_UINT8(scr, SerialState), 615 VMSTATE_UINT8_V(fcr_vmstate, SerialState, 3), 616 VMSTATE_END_OF_LIST() 617 } 618 }; 619 620 static void serial_reset(void *opaque) 621 { 622 SerialState *s = opaque; 623 624 s->rbr = 0; 625 s->ier = 0; 626 s->iir = UART_IIR_NO_INT; 627 s->lcr = 0; 628 s->lsr = UART_LSR_TEMT | UART_LSR_THRE; 629 s->msr = UART_MSR_DCD | UART_MSR_DSR | UART_MSR_CTS; 630 /* Default to 9600 baud, 1 start bit, 8 data bits, 1 stop bit, no parity. */ 631 s->divider = 0x0C; 632 s->mcr = UART_MCR_OUT2; 633 s->scr = 0; 634 s->tsr_retry = 0; 635 s->char_transmit_time = (get_ticks_per_sec() / 9600) * 10; 636 s->poll_msl = 0; 637 638 fifo8_reset(&s->recv_fifo); 639 fifo8_reset(&s->xmit_fifo); 640 641 s->last_xmit_ts = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL); 642 643 s->thr_ipending = 0; 644 s->last_break_enable = 0; 645 qemu_irq_lower(s->irq); 646 } 647 648 void serial_realize_core(SerialState *s, Error **errp) 649 { 650 if (!s->chr) { 651 error_setg(errp, "Can't create serial device, empty char device"); 652 return; 653 } 654 655 s->modem_status_poll = timer_new_ns(QEMU_CLOCK_VIRTUAL, (QEMUTimerCB *) serial_update_msl, s); 656 657 s->fifo_timeout_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, (QEMUTimerCB *) fifo_timeout_int, s); 658 qemu_register_reset(serial_reset, s); 659 660 qemu_chr_add_handlers(s->chr, serial_can_receive1, serial_receive1, 661 serial_event, s); 662 fifo8_create(&s->recv_fifo, UART_FIFO_LENGTH); 663 fifo8_create(&s->xmit_fifo, UART_FIFO_LENGTH); 664 } 665 666 void serial_exit_core(SerialState *s) 667 { 668 qemu_chr_add_handlers(s->chr, NULL, NULL, NULL, NULL); 669 qemu_unregister_reset(serial_reset, s); 670 } 671 672 /* Change the main reference oscillator frequency. */ 673 void serial_set_frequency(SerialState *s, uint32_t frequency) 674 { 675 s->baudbase = frequency; 676 serial_update_parameters(s); 677 } 678 679 const MemoryRegionOps serial_io_ops = { 680 .read = serial_ioport_read, 681 .write = serial_ioport_write, 682 .impl = { 683 .min_access_size = 1, 684 .max_access_size = 1, 685 }, 686 .endianness = DEVICE_LITTLE_ENDIAN, 687 }; 688 689 SerialState *serial_init(int base, qemu_irq irq, int baudbase, 690 CharDriverState *chr, MemoryRegion *system_io) 691 { 692 SerialState *s; 693 Error *err = NULL; 694 695 s = g_malloc0(sizeof(SerialState)); 696 697 s->irq = irq; 698 s->baudbase = baudbase; 699 s->chr = chr; 700 serial_realize_core(s, &err); 701 if (err != NULL) { 702 error_report("%s", error_get_pretty(err)); 703 error_free(err); 704 exit(1); 705 } 706 707 vmstate_register(NULL, base, &vmstate_serial, s); 708 709 memory_region_init_io(&s->io, NULL, &serial_io_ops, s, "serial", 8); 710 memory_region_add_subregion(system_io, base, &s->io); 711 712 return s; 713 } 714 715 /* Memory mapped interface */ 716 static uint64_t serial_mm_read(void *opaque, hwaddr addr, 717 unsigned size) 718 { 719 SerialState *s = opaque; 720 return serial_ioport_read(s, addr >> s->it_shift, 1); 721 } 722 723 static void serial_mm_write(void *opaque, hwaddr addr, 724 uint64_t value, unsigned size) 725 { 726 SerialState *s = opaque; 727 value &= ~0u >> (32 - (size * 8)); 728 serial_ioport_write(s, addr >> s->it_shift, value, 1); 729 } 730 731 static const MemoryRegionOps serial_mm_ops[3] = { 732 [DEVICE_NATIVE_ENDIAN] = { 733 .read = serial_mm_read, 734 .write = serial_mm_write, 735 .endianness = DEVICE_NATIVE_ENDIAN, 736 }, 737 [DEVICE_LITTLE_ENDIAN] = { 738 .read = serial_mm_read, 739 .write = serial_mm_write, 740 .endianness = DEVICE_LITTLE_ENDIAN, 741 }, 742 [DEVICE_BIG_ENDIAN] = { 743 .read = serial_mm_read, 744 .write = serial_mm_write, 745 .endianness = DEVICE_BIG_ENDIAN, 746 }, 747 }; 748 749 SerialState *serial_mm_init(MemoryRegion *address_space, 750 hwaddr base, int it_shift, 751 qemu_irq irq, int baudbase, 752 CharDriverState *chr, enum device_endian end) 753 { 754 SerialState *s; 755 Error *err = NULL; 756 757 s = g_malloc0(sizeof(SerialState)); 758 759 s->it_shift = it_shift; 760 s->irq = irq; 761 s->baudbase = baudbase; 762 s->chr = chr; 763 764 serial_realize_core(s, &err); 765 if (err != NULL) { 766 error_report("%s", error_get_pretty(err)); 767 error_free(err); 768 exit(1); 769 } 770 vmstate_register(NULL, base, &vmstate_serial, s); 771 772 memory_region_init_io(&s->io, NULL, &serial_mm_ops[end], s, 773 "serial", 8 << it_shift); 774 memory_region_add_subregion(address_space, base, &s->io); 775 776 serial_update_msl(s); 777 return s; 778 } 779