| /* |
| * QEMU 16550A UART emulation |
| * |
| * Copyright (c) 2003-2004 Fabrice Bellard |
| * Copyright (c) 2008 Citrix Systems, Inc. |
| * |
| * Permission is hereby granted, free of charge, to any person obtaining a copy |
| * of this software and associated documentation files (the "Software"), to deal |
| * in the Software without restriction, including without limitation the rights |
| * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| * copies of the Software, and to permit persons to whom the Software is |
| * furnished to do so, subject to the following conditions: |
| * |
| * The above copyright notice and this permission notice shall be included in |
| * all copies or substantial portions of the Software. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL |
| * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN |
| * THE SOFTWARE. |
| */ |
| |
| #include "qemu/osdep.h" |
| #include "qemu/bitops.h" |
| #include "hw/char/serial.h" |
| #include "hw/irq.h" |
| #include "migration/vmstate.h" |
| #include "chardev/char-serial.h" |
| #include "qapi/error.h" |
| #include "qemu/timer.h" |
| #include "system/reset.h" |
| #include "system/runstate.h" |
| #include "qemu/error-report.h" |
| #include "trace.h" |
| #include "hw/qdev-properties.h" |
| #include "hw/qdev-properties-system.h" |
| |
| #define UART_LCR_DLAB 0x80 /* Divisor latch access bit */ |
| |
| #define UART_IER_MSI 0x08 /* Enable Modem status interrupt */ |
| #define UART_IER_RLSI 0x04 /* Enable receiver line status interrupt */ |
| #define UART_IER_THRI 0x02 /* Enable Transmitter holding register int. */ |
| #define UART_IER_RDI 0x01 /* Enable receiver data interrupt */ |
| |
| #define UART_IIR_NO_INT 0x01 /* No interrupts pending */ |
| #define UART_IIR_ID 0x06 /* Mask for the interrupt ID */ |
| |
| #define UART_IIR_MSI 0x00 /* Modem status interrupt */ |
| #define UART_IIR_THRI 0x02 /* Transmitter holding register empty */ |
| #define UART_IIR_RDI 0x04 /* Receiver data interrupt */ |
| #define UART_IIR_RLSI 0x06 /* Receiver line status interrupt */ |
| #define UART_IIR_CTI 0x0C /* Character Timeout Indication */ |
| |
| #define UART_IIR_FENF 0x80 /* Fifo enabled, but not functioning */ |
| #define UART_IIR_FE 0xC0 /* Fifo enabled */ |
| |
| /* |
| * These are the definitions for the Modem Control Register |
| */ |
| #define UART_MCR_LOOP 0x10 /* Enable loopback test mode */ |
| #define UART_MCR_OUT2 0x08 /* Out2 complement */ |
| #define UART_MCR_OUT1 0x04 /* Out1 complement */ |
| #define UART_MCR_RTS 0x02 /* RTS complement */ |
| #define UART_MCR_DTR 0x01 /* DTR complement */ |
| |
| /* |
| * These are the definitions for the Modem Status Register |
| */ |
| #define UART_MSR_DCD 0x80 /* Data Carrier Detect */ |
| #define UART_MSR_RI 0x40 /* Ring Indicator */ |
| #define UART_MSR_DSR 0x20 /* Data Set Ready */ |
| #define UART_MSR_CTS 0x10 /* Clear to Send */ |
| #define UART_MSR_DDCD 0x08 /* Delta DCD */ |
| #define UART_MSR_TERI 0x04 /* Trailing edge ring indicator */ |
| #define UART_MSR_DDSR 0x02 /* Delta DSR */ |
| #define UART_MSR_DCTS 0x01 /* Delta CTS */ |
| #define UART_MSR_ANY_DELTA 0x0F /* Any of the delta bits! */ |
| |
| #define UART_LSR_TEMT 0x40 /* Transmitter empty */ |
| #define UART_LSR_THRE 0x20 /* Transmit-hold-register empty */ |
| #define UART_LSR_BI 0x10 /* Break interrupt indicator */ |
| #define UART_LSR_FE 0x08 /* Frame error indicator */ |
| #define UART_LSR_PE 0x04 /* Parity error indicator */ |
| #define UART_LSR_OE 0x02 /* Overrun error indicator */ |
| #define UART_LSR_DR 0x01 /* Receiver data ready */ |
| #define UART_LSR_INT_ANY 0x1E /* Any of the lsr-interrupt-triggering status bits */ |
| |
| /* Interrupt trigger levels. The byte-counts are for 16550A - in newer UARTs the byte-count for each ITL is higher. */ |
| |
| #define UART_FCR_ITL_1 0x00 /* 1 byte ITL */ |
| #define UART_FCR_ITL_2 0x40 /* 4 bytes ITL */ |
| #define UART_FCR_ITL_3 0x80 /* 8 bytes ITL */ |
| #define UART_FCR_ITL_4 0xC0 /* 14 bytes ITL */ |
| |
| #define UART_FCR_DMS 0x08 /* DMA Mode Select */ |
| #define UART_FCR_XFR 0x04 /* XMIT Fifo Reset */ |
| #define UART_FCR_RFR 0x02 /* RCVR Fifo Reset */ |
| #define UART_FCR_FE 0x01 /* FIFO Enable */ |
| |
| #define MAX_XMIT_RETRY 4 |
| |
| static void serial_receive1(void *opaque, const uint8_t *buf, int size); |
| static void serial_xmit(SerialState *s); |
| |
| static inline void recv_fifo_put(SerialState *s, uint8_t chr) |
| { |
| /* Receive overruns do not overwrite FIFO contents. */ |
| if (!fifo8_is_full(&s->recv_fifo)) { |
| fifo8_push(&s->recv_fifo, chr); |
| } else { |
| s->lsr |= UART_LSR_OE; |
| } |
| } |
| |
| static void serial_update_irq(SerialState *s) |
| { |
| uint8_t tmp_iir = UART_IIR_NO_INT; |
| |
| if ((s->ier & UART_IER_RLSI) && (s->lsr & UART_LSR_INT_ANY)) { |
| tmp_iir = UART_IIR_RLSI; |
| } else if ((s->ier & UART_IER_RDI) && s->timeout_ipending) { |
| /* Note that(s->ier & UART_IER_RDI) can mask this interrupt, |
| * this is not in the specification but is observed on existing |
| * hardware. */ |
| tmp_iir = UART_IIR_CTI; |
| } else if ((s->ier & UART_IER_RDI) && (s->lsr & UART_LSR_DR) && |
| (!(s->fcr & UART_FCR_FE) || |
| s->recv_fifo.num >= s->recv_fifo_itl)) { |
| tmp_iir = UART_IIR_RDI; |
| } else if ((s->ier & UART_IER_THRI) && s->thr_ipending) { |
| tmp_iir = UART_IIR_THRI; |
| } else if ((s->ier & UART_IER_MSI) && (s->msr & UART_MSR_ANY_DELTA)) { |
| tmp_iir = UART_IIR_MSI; |
| } |
| |
| s->iir = tmp_iir | (s->iir & 0xF0); |
| |
| if (tmp_iir != UART_IIR_NO_INT) { |
| qemu_irq_raise(s->irq); |
| } else { |
| qemu_irq_lower(s->irq); |
| } |
| } |
| |
| static void serial_update_parameters(SerialState *s) |
| { |
| float speed; |
| int parity, data_bits, stop_bits, frame_size; |
| QEMUSerialSetParams ssp; |
| |
| /* Start bit. */ |
| frame_size = 1; |
| if (s->lcr & 0x08) { |
| /* Parity bit. */ |
| frame_size++; |
| if (s->lcr & 0x10) |
| parity = 'E'; |
| else |
| parity = 'O'; |
| } else { |
| parity = 'N'; |
| } |
| if (s->lcr & 0x04) { |
| stop_bits = 2; |
| } else { |
| stop_bits = 1; |
| } |
| |
| data_bits = (s->lcr & 0x03) + 5; |
| frame_size += data_bits + stop_bits; |
| /* Zero divisor should give about 3500 baud */ |
| speed = (s->divider == 0) ? 3500 : (float) s->baudbase / s->divider; |
| ssp.speed = speed; |
| ssp.parity = parity; |
| ssp.data_bits = data_bits; |
| ssp.stop_bits = stop_bits; |
| s->char_transmit_time = (NANOSECONDS_PER_SECOND / speed) * frame_size; |
| qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_SERIAL_SET_PARAMS, &ssp); |
| trace_serial_update_parameters(speed, parity, data_bits, stop_bits); |
| } |
| |
| static void serial_update_msl(SerialState *s) |
| { |
| uint8_t omsr; |
| int flags; |
| |
| timer_del(s->modem_status_poll); |
| |
| if (qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_SERIAL_GET_TIOCM, |
| &flags) == -ENOTSUP) { |
| s->poll_msl = -1; |
| return; |
| } |
| |
| omsr = s->msr; |
| |
| s->msr = (flags & CHR_TIOCM_CTS) ? s->msr | UART_MSR_CTS : s->msr & ~UART_MSR_CTS; |
| s->msr = (flags & CHR_TIOCM_DSR) ? s->msr | UART_MSR_DSR : s->msr & ~UART_MSR_DSR; |
| s->msr = (flags & CHR_TIOCM_CAR) ? s->msr | UART_MSR_DCD : s->msr & ~UART_MSR_DCD; |
| s->msr = (flags & CHR_TIOCM_RI) ? s->msr | UART_MSR_RI : s->msr & ~UART_MSR_RI; |
| |
| if (s->msr != omsr) { |
| /* Set delta bits */ |
| s->msr = s->msr | ((s->msr >> 4) ^ (omsr >> 4)); |
| /* UART_MSR_TERI only if change was from 1 -> 0 */ |
| if ((s->msr & UART_MSR_TERI) && !(omsr & UART_MSR_RI)) |
| s->msr &= ~UART_MSR_TERI; |
| serial_update_irq(s); |
| } |
| |
| /* The real 16550A apparently has a 250ns response latency to line status changes. |
| We'll be lazy and poll only every 10ms, and only poll it at all if MSI interrupts are turned on */ |
| |
| if (s->poll_msl) { |
| timer_mod(s->modem_status_poll, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + |
| NANOSECONDS_PER_SECOND / 100); |
| } |
| } |
| |
| static gboolean serial_watch_cb(void *do_not_use, GIOCondition cond, |
| void *opaque) |
| { |
| SerialState *s = opaque; |
| s->watch_tag = 0; |
| serial_xmit(s); |
| return G_SOURCE_REMOVE; |
| } |
| |
| static void serial_xmit(SerialState *s) |
| { |
| do { |
| assert(!(s->lsr & UART_LSR_TEMT)); |
| if (s->tsr_retry == 0) { |
| assert(!(s->lsr & UART_LSR_THRE)); |
| |
| if (s->fcr & UART_FCR_FE) { |
| assert(!fifo8_is_empty(&s->xmit_fifo)); |
| s->tsr = fifo8_pop(&s->xmit_fifo); |
| if (!s->xmit_fifo.num) { |
| s->lsr |= UART_LSR_THRE; |
| } |
| } else { |
| s->tsr = s->thr; |
| s->lsr |= UART_LSR_THRE; |
| } |
| if ((s->lsr & UART_LSR_THRE) && !s->thr_ipending) { |
| s->thr_ipending = 1; |
| serial_update_irq(s); |
| } |
| } |
| |
| if (s->mcr & UART_MCR_LOOP) { |
| /* in loopback mode, say that we just received a char */ |
| serial_receive1(s, &s->tsr, 1); |
| } else { |
| int rc = qemu_chr_fe_write(&s->chr, &s->tsr, 1); |
| |
| if ((rc == 0 || |
| (rc == -1 && errno == EAGAIN)) && |
| s->tsr_retry < MAX_XMIT_RETRY) { |
| assert(s->watch_tag == 0); |
| s->watch_tag = |
| qemu_chr_fe_add_watch(&s->chr, G_IO_OUT | G_IO_HUP, |
| serial_watch_cb, s); |
| if (s->watch_tag > 0) { |
| s->tsr_retry++; |
| return; |
| } |
| } |
| } |
| s->tsr_retry = 0; |
| |
| /* Transmit another byte if it is already available. It is only |
| possible when FIFO is enabled and not empty. */ |
| } while (!(s->lsr & UART_LSR_THRE)); |
| |
| s->last_xmit_ts = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL); |
| s->lsr |= UART_LSR_TEMT; |
| } |
| |
| /* Setter for FCR. |
| is_load flag means, that value is set while loading VM state |
| and interrupt should not be invoked */ |
| static void serial_write_fcr(SerialState *s, uint8_t val) |
| { |
| /* Set fcr - val only has the bits that are supposed to "stick" */ |
| s->fcr = val; |
| |
| if (val & UART_FCR_FE) { |
| s->iir |= UART_IIR_FE; |
| /* Set recv_fifo trigger Level */ |
| switch (val & 0xC0) { |
| case UART_FCR_ITL_1: |
| s->recv_fifo_itl = 1; |
| break; |
| case UART_FCR_ITL_2: |
| s->recv_fifo_itl = 4; |
| break; |
| case UART_FCR_ITL_3: |
| s->recv_fifo_itl = 8; |
| break; |
| case UART_FCR_ITL_4: |
| s->recv_fifo_itl = 14; |
| break; |
| } |
| } else { |
| s->iir &= ~UART_IIR_FE; |
| } |
| } |
| |
| static void serial_update_tiocm(SerialState *s) |
| { |
| int flags; |
| |
| qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_SERIAL_GET_TIOCM, &flags); |
| |
| flags &= ~(CHR_TIOCM_RTS | CHR_TIOCM_DTR); |
| |
| if (s->mcr & UART_MCR_RTS) { |
| flags |= CHR_TIOCM_RTS; |
| } |
| if (s->mcr & UART_MCR_DTR) { |
| flags |= CHR_TIOCM_DTR; |
| } |
| |
| qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_SERIAL_SET_TIOCM, &flags); |
| } |
| |
| static void serial_ioport_write(void *opaque, hwaddr addr, uint64_t val, |
| unsigned size) |
| { |
| SerialState *s = opaque; |
| |
| assert(size == 1 && addr < 8); |
| trace_serial_write(addr, val); |
| switch(addr) { |
| default: |
| case 0: |
| if (s->lcr & UART_LCR_DLAB) { |
| s->divider = deposit32(s->divider, 8 * addr, 8, val); |
| serial_update_parameters(s); |
| } else { |
| s->thr = (uint8_t) val; |
| if(s->fcr & UART_FCR_FE) { |
| /* xmit overruns overwrite data, so make space if needed */ |
| if (fifo8_is_full(&s->xmit_fifo)) { |
| fifo8_pop(&s->xmit_fifo); |
| } |
| fifo8_push(&s->xmit_fifo, s->thr); |
| } |
| s->thr_ipending = 0; |
| s->lsr &= ~UART_LSR_THRE; |
| s->lsr &= ~UART_LSR_TEMT; |
| serial_update_irq(s); |
| if (s->tsr_retry == 0) { |
| serial_xmit(s); |
| } |
| } |
| break; |
| case 1: |
| if (s->lcr & UART_LCR_DLAB) { |
| s->divider = deposit32(s->divider, 8 * addr, 8, val); |
| serial_update_parameters(s); |
| } else { |
| uint8_t changed = (s->ier ^ val) & 0x0f; |
| s->ier = val & 0x0f; |
| /* If the backend device is a real serial port, turn polling of the modem |
| * status lines on physical port on or off depending on UART_IER_MSI state. |
| */ |
| if ((changed & UART_IER_MSI) && s->poll_msl >= 0) { |
| if (s->ier & UART_IER_MSI) { |
| s->poll_msl = 1; |
| serial_update_msl(s); |
| } else { |
| timer_del(s->modem_status_poll); |
| s->poll_msl = 0; |
| } |
| } |
| |
| /* Turning on the THRE interrupt on IER can trigger the interrupt |
| * if LSR.THRE=1, even if it had been masked before by reading IIR. |
| * This is not in the datasheet, but Windows relies on it. It is |
| * unclear if THRE has to be resampled every time THRI becomes |
| * 1, or only on the rising edge. Bochs does the latter, and Windows |
| * always toggles IER to all zeroes and back to all ones, so do the |
| * same. |
| * |
| * If IER.THRI is zero, thr_ipending is not used. Set it to zero |
| * so that the thr_ipending subsection is not migrated. |
| */ |
| if (changed & UART_IER_THRI) { |
| if ((s->ier & UART_IER_THRI) && (s->lsr & UART_LSR_THRE)) { |
| s->thr_ipending = 1; |
| } else { |
| s->thr_ipending = 0; |
| } |
| } |
| |
| if (changed) { |
| serial_update_irq(s); |
| } |
| } |
| break; |
| case 2: |
| /* Did the enable/disable flag change? If so, make sure FIFOs get flushed */ |
| if ((val ^ s->fcr) & UART_FCR_FE) { |
| val |= UART_FCR_XFR | UART_FCR_RFR; |
| } |
| |
| /* FIFO clear */ |
| |
| if (val & UART_FCR_RFR) { |
| s->lsr &= ~(UART_LSR_DR | UART_LSR_BI); |
| timer_del(s->fifo_timeout_timer); |
| s->timeout_ipending = 0; |
| fifo8_reset(&s->recv_fifo); |
| } |
| |
| if (val & UART_FCR_XFR) { |
| s->lsr |= UART_LSR_THRE; |
| s->thr_ipending = 1; |
| fifo8_reset(&s->xmit_fifo); |
| } |
| |
| serial_write_fcr(s, val & 0xC9); |
| serial_update_irq(s); |
| break; |
| case 3: |
| { |
| int break_enable; |
| s->lcr = val; |
| serial_update_parameters(s); |
| break_enable = (val >> 6) & 1; |
| if (break_enable != s->last_break_enable) { |
| s->last_break_enable = break_enable; |
| qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_SERIAL_SET_BREAK, |
| &break_enable); |
| } |
| } |
| break; |
| case 4: |
| { |
| int old_mcr = s->mcr; |
| s->mcr = val & 0x1f; |
| if (val & UART_MCR_LOOP) |
| break; |
| |
| if (s->poll_msl >= 0 && old_mcr != s->mcr) { |
| serial_update_tiocm(s); |
| /* Update the modem status after a one-character-send wait-time, since there may be a response |
| from the device/computer at the other end of the serial line */ |
| timer_mod(s->modem_status_poll, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + s->char_transmit_time); |
| } |
| } |
| break; |
| case 5: |
| break; |
| case 6: |
| break; |
| case 7: |
| s->scr = val; |
| break; |
| } |
| } |
| |
| static uint64_t serial_ioport_read(void *opaque, hwaddr addr, unsigned size) |
| { |
| SerialState *s = opaque; |
| uint32_t ret; |
| |
| assert(size == 1 && addr < 8); |
| switch(addr) { |
| default: |
| case 0: |
| if (s->lcr & UART_LCR_DLAB) { |
| ret = extract16(s->divider, 8 * addr, 8); |
| } else { |
| if(s->fcr & UART_FCR_FE) { |
| ret = fifo8_is_empty(&s->recv_fifo) ? |
| 0 : fifo8_pop(&s->recv_fifo); |
| if (s->recv_fifo.num == 0) { |
| s->lsr &= ~(UART_LSR_DR | UART_LSR_BI); |
| } else { |
| timer_mod(s->fifo_timeout_timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + s->char_transmit_time * 4); |
| } |
| s->timeout_ipending = 0; |
| } else { |
| ret = s->rbr; |
| s->lsr &= ~(UART_LSR_DR | UART_LSR_BI); |
| } |
| serial_update_irq(s); |
| if (!(s->mcr & UART_MCR_LOOP)) { |
| /* in loopback mode, don't receive any data */ |
| qemu_chr_fe_accept_input(&s->chr); |
| } |
| } |
| break; |
| case 1: |
| if (s->lcr & UART_LCR_DLAB) { |
| ret = extract16(s->divider, 8 * addr, 8); |
| } else { |
| ret = s->ier; |
| } |
| break; |
| case 2: |
| ret = s->iir; |
| if ((ret & UART_IIR_ID) == UART_IIR_THRI) { |
| s->thr_ipending = 0; |
| serial_update_irq(s); |
| } |
| break; |
| case 3: |
| ret = s->lcr; |
| break; |
| case 4: |
| ret = s->mcr; |
| break; |
| case 5: |
| ret = s->lsr; |
| /* Clear break and overrun interrupts */ |
| if (s->lsr & (UART_LSR_BI|UART_LSR_OE)) { |
| s->lsr &= ~(UART_LSR_BI|UART_LSR_OE); |
| serial_update_irq(s); |
| } |
| break; |
| case 6: |
| if (s->mcr & UART_MCR_LOOP) { |
| /* in loopback, the modem output pins are connected to the |
| inputs */ |
| ret = (s->mcr & 0x0c) << 4; |
| ret |= (s->mcr & 0x02) << 3; |
| ret |= (s->mcr & 0x01) << 5; |
| } else { |
| if (s->poll_msl >= 0) |
| serial_update_msl(s); |
| ret = s->msr; |
| /* Clear delta bits & msr int after read, if they were set */ |
| if (s->msr & UART_MSR_ANY_DELTA) { |
| s->msr &= 0xF0; |
| serial_update_irq(s); |
| } |
| } |
| break; |
| case 7: |
| ret = s->scr; |
| break; |
| } |
| trace_serial_read(addr, ret); |
| return ret; |
| } |
| |
| static int serial_can_receive(SerialState *s) |
| { |
| if(s->fcr & UART_FCR_FE) { |
| if (s->recv_fifo.num < UART_FIFO_LENGTH) { |
| /* |
| * Advertise (fifo.itl - fifo.count) bytes when count < ITL, and 1 |
| * if above. If UART_FIFO_LENGTH - fifo.count is advertised the |
| * effect will be to almost always fill the fifo completely before |
| * the guest has a chance to respond, effectively overriding the ITL |
| * that the guest has set. |
| */ |
| return (s->recv_fifo.num <= s->recv_fifo_itl) ? |
| s->recv_fifo_itl - s->recv_fifo.num : 1; |
| } else { |
| return 0; |
| } |
| } else { |
| return !(s->lsr & UART_LSR_DR); |
| } |
| } |
| |
| static void serial_receive_break(SerialState *s) |
| { |
| s->rbr = 0; |
| /* When the LSR_DR is set a null byte is pushed into the fifo */ |
| recv_fifo_put(s, '\0'); |
| s->lsr |= UART_LSR_BI | UART_LSR_DR; |
| serial_update_irq(s); |
| } |
| |
| /* There's data in recv_fifo and s->rbr has not been read for 4 char transmit times */ |
| static void fifo_timeout_int (void *opaque) { |
| SerialState *s = opaque; |
| if (s->recv_fifo.num) { |
| s->timeout_ipending = 1; |
| serial_update_irq(s); |
| } |
| } |
| |
| static int serial_can_receive1(void *opaque) |
| { |
| SerialState *s = opaque; |
| return serial_can_receive(s); |
| } |
| |
| static void serial_receive1(void *opaque, const uint8_t *buf, int size) |
| { |
| SerialState *s = opaque; |
| |
| if (s->wakeup) { |
| qemu_system_wakeup_request(QEMU_WAKEUP_REASON_OTHER, NULL); |
| } |
| if(s->fcr & UART_FCR_FE) { |
| int i; |
| for (i = 0; i < size; i++) { |
| recv_fifo_put(s, buf[i]); |
| } |
| s->lsr |= UART_LSR_DR; |
| /* call the timeout receive callback in 4 char transmit time */ |
| timer_mod(s->fifo_timeout_timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + s->char_transmit_time * 4); |
| } else { |
| if (s->lsr & UART_LSR_DR) |
| s->lsr |= UART_LSR_OE; |
| s->rbr = buf[0]; |
| s->lsr |= UART_LSR_DR; |
| } |
| serial_update_irq(s); |
| } |
| |
| static void serial_event(void *opaque, QEMUChrEvent event) |
| { |
| SerialState *s = opaque; |
| if (event == CHR_EVENT_BREAK) |
| serial_receive_break(s); |
| } |
| |
| static int serial_pre_save(void *opaque) |
| { |
| SerialState *s = opaque; |
| s->fcr_vmstate = s->fcr; |
| |
| return 0; |
| } |
| |
| static int serial_pre_load(void *opaque) |
| { |
| SerialState *s = opaque; |
| s->thr_ipending = -1; |
| s->poll_msl = -1; |
| return 0; |
| } |
| |
| static int serial_post_load(void *opaque, int version_id) |
| { |
| SerialState *s = opaque; |
| |
| if (version_id < 3) { |
| s->fcr_vmstate = 0; |
| } |
| if (s->thr_ipending == -1) { |
| s->thr_ipending = ((s->iir & UART_IIR_ID) == UART_IIR_THRI); |
| } |
| |
| if (s->tsr_retry > 0) { |
| /* tsr_retry > 0 implies LSR.TEMT = 0 (transmitter not empty). */ |
| if (s->lsr & UART_LSR_TEMT) { |
| error_report("inconsistent state in serial device " |
| "(tsr empty, tsr_retry=%d", s->tsr_retry); |
| return -1; |
| } |
| |
| if (s->tsr_retry > MAX_XMIT_RETRY) { |
| s->tsr_retry = MAX_XMIT_RETRY; |
| } |
| |
| assert(s->watch_tag == 0); |
| s->watch_tag = qemu_chr_fe_add_watch(&s->chr, G_IO_OUT | G_IO_HUP, |
| serial_watch_cb, s); |
| } else { |
| /* tsr_retry == 0 implies LSR.TEMT = 1 (transmitter empty). */ |
| if (!(s->lsr & UART_LSR_TEMT)) { |
| error_report("inconsistent state in serial device " |
| "(tsr not empty, tsr_retry=0"); |
| return -1; |
| } |
| } |
| |
| s->last_break_enable = (s->lcr >> 6) & 1; |
| /* Initialize fcr via setter to perform essential side-effects */ |
| serial_write_fcr(s, s->fcr_vmstate); |
| serial_update_parameters(s); |
| return 0; |
| } |
| |
| static bool serial_thr_ipending_needed(void *opaque) |
| { |
| SerialState *s = opaque; |
| |
| if (s->ier & UART_IER_THRI) { |
| bool expected_value = ((s->iir & UART_IIR_ID) == UART_IIR_THRI); |
| return s->thr_ipending != expected_value; |
| } else { |
| /* LSR.THRE will be sampled again when the interrupt is |
| * enabled. thr_ipending is not used in this case, do |
| * not migrate it. |
| */ |
| return false; |
| } |
| } |
| |
| static const VMStateDescription vmstate_serial_thr_ipending = { |
| .name = "serial/thr_ipending", |
| .version_id = 1, |
| .minimum_version_id = 1, |
| .needed = serial_thr_ipending_needed, |
| .fields = (const VMStateField[]) { |
| VMSTATE_INT32(thr_ipending, SerialState), |
| VMSTATE_END_OF_LIST() |
| } |
| }; |
| |
| static bool serial_tsr_needed(void *opaque) |
| { |
| SerialState *s = (SerialState *)opaque; |
| return s->tsr_retry != 0; |
| } |
| |
| static const VMStateDescription vmstate_serial_tsr = { |
| .name = "serial/tsr", |
| .version_id = 1, |
| .minimum_version_id = 1, |
| .needed = serial_tsr_needed, |
| .fields = (const VMStateField[]) { |
| VMSTATE_UINT32(tsr_retry, SerialState), |
| VMSTATE_UINT8(thr, SerialState), |
| VMSTATE_UINT8(tsr, SerialState), |
| VMSTATE_END_OF_LIST() |
| } |
| }; |
| |
| static bool serial_recv_fifo_needed(void *opaque) |
| { |
| SerialState *s = (SerialState *)opaque; |
| return !fifo8_is_empty(&s->recv_fifo); |
| |
| } |
| |
| static const VMStateDescription vmstate_serial_recv_fifo = { |
| .name = "serial/recv_fifo", |
| .version_id = 1, |
| .minimum_version_id = 1, |
| .needed = serial_recv_fifo_needed, |
| .fields = (const VMStateField[]) { |
| VMSTATE_STRUCT(recv_fifo, SerialState, 1, vmstate_fifo8, Fifo8), |
| VMSTATE_END_OF_LIST() |
| } |
| }; |
| |
| static bool serial_xmit_fifo_needed(void *opaque) |
| { |
| SerialState *s = (SerialState *)opaque; |
| return !fifo8_is_empty(&s->xmit_fifo); |
| } |
| |
| static const VMStateDescription vmstate_serial_xmit_fifo = { |
| .name = "serial/xmit_fifo", |
| .version_id = 1, |
| .minimum_version_id = 1, |
| .needed = serial_xmit_fifo_needed, |
| .fields = (const VMStateField[]) { |
| VMSTATE_STRUCT(xmit_fifo, SerialState, 1, vmstate_fifo8, Fifo8), |
| VMSTATE_END_OF_LIST() |
| } |
| }; |
| |
| static bool serial_fifo_timeout_timer_needed(void *opaque) |
| { |
| SerialState *s = (SerialState *)opaque; |
| return timer_pending(s->fifo_timeout_timer); |
| } |
| |
| static const VMStateDescription vmstate_serial_fifo_timeout_timer = { |
| .name = "serial/fifo_timeout_timer", |
| .version_id = 1, |
| .minimum_version_id = 1, |
| .needed = serial_fifo_timeout_timer_needed, |
| .fields = (const VMStateField[]) { |
| VMSTATE_TIMER_PTR(fifo_timeout_timer, SerialState), |
| VMSTATE_END_OF_LIST() |
| } |
| }; |
| |
| static bool serial_timeout_ipending_needed(void *opaque) |
| { |
| SerialState *s = (SerialState *)opaque; |
| return s->timeout_ipending != 0; |
| } |
| |
| static const VMStateDescription vmstate_serial_timeout_ipending = { |
| .name = "serial/timeout_ipending", |
| .version_id = 1, |
| .minimum_version_id = 1, |
| .needed = serial_timeout_ipending_needed, |
| .fields = (const VMStateField[]) { |
| VMSTATE_INT32(timeout_ipending, SerialState), |
| VMSTATE_END_OF_LIST() |
| } |
| }; |
| |
| static bool serial_poll_needed(void *opaque) |
| { |
| SerialState *s = (SerialState *)opaque; |
| return s->poll_msl >= 0; |
| } |
| |
| static const VMStateDescription vmstate_serial_poll = { |
| .name = "serial/poll", |
| .version_id = 1, |
| .needed = serial_poll_needed, |
| .minimum_version_id = 1, |
| .fields = (const VMStateField[]) { |
| VMSTATE_INT32(poll_msl, SerialState), |
| VMSTATE_TIMER_PTR(modem_status_poll, SerialState), |
| VMSTATE_END_OF_LIST() |
| } |
| }; |
| |
| const VMStateDescription vmstate_serial = { |
| .name = "serial", |
| .version_id = 3, |
| .minimum_version_id = 2, |
| .pre_save = serial_pre_save, |
| .pre_load = serial_pre_load, |
| .post_load = serial_post_load, |
| .fields = (const VMStateField[]) { |
| VMSTATE_UINT16_V(divider, SerialState, 2), |
| VMSTATE_UINT8(rbr, SerialState), |
| VMSTATE_UINT8(ier, SerialState), |
| VMSTATE_UINT8(iir, SerialState), |
| VMSTATE_UINT8(lcr, SerialState), |
| VMSTATE_UINT8(mcr, SerialState), |
| VMSTATE_UINT8(lsr, SerialState), |
| VMSTATE_UINT8(msr, SerialState), |
| VMSTATE_UINT8(scr, SerialState), |
| VMSTATE_UINT8_V(fcr_vmstate, SerialState, 3), |
| VMSTATE_END_OF_LIST() |
| }, |
| .subsections = (const VMStateDescription * const []) { |
| &vmstate_serial_thr_ipending, |
| &vmstate_serial_tsr, |
| &vmstate_serial_recv_fifo, |
| &vmstate_serial_xmit_fifo, |
| &vmstate_serial_fifo_timeout_timer, |
| &vmstate_serial_timeout_ipending, |
| &vmstate_serial_poll, |
| NULL |
| } |
| }; |
| |
| static void serial_reset(void *opaque) |
| { |
| SerialState *s = opaque; |
| |
| if (s->watch_tag > 0) { |
| g_source_remove(s->watch_tag); |
| s->watch_tag = 0; |
| } |
| |
| s->rbr = 0; |
| s->ier = 0; |
| s->iir = UART_IIR_NO_INT; |
| s->lcr = 0; |
| s->lsr = UART_LSR_TEMT | UART_LSR_THRE; |
| s->msr = UART_MSR_DCD | UART_MSR_DSR | UART_MSR_CTS; |
| /* Default to 9600 baud, 1 start bit, 8 data bits, 1 stop bit, no parity. */ |
| s->divider = 0x0C; |
| s->mcr = UART_MCR_OUT2; |
| s->scr = 0; |
| s->tsr_retry = 0; |
| s->char_transmit_time = (NANOSECONDS_PER_SECOND / 9600) * 10; |
| s->poll_msl = 0; |
| |
| s->timeout_ipending = 0; |
| timer_del(s->fifo_timeout_timer); |
| timer_del(s->modem_status_poll); |
| |
| fifo8_reset(&s->recv_fifo); |
| fifo8_reset(&s->xmit_fifo); |
| |
| s->last_xmit_ts = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL); |
| |
| s->thr_ipending = 0; |
| s->last_break_enable = 0; |
| qemu_irq_lower(s->irq); |
| |
| serial_update_msl(s); |
| s->msr &= ~UART_MSR_ANY_DELTA; |
| } |
| |
| static int serial_be_change(void *opaque) |
| { |
| SerialState *s = opaque; |
| |
| qemu_chr_fe_set_handlers(&s->chr, serial_can_receive1, serial_receive1, |
| serial_event, serial_be_change, s, NULL, true); |
| |
| serial_update_parameters(s); |
| |
| qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_SERIAL_SET_BREAK, |
| &s->last_break_enable); |
| |
| s->poll_msl = (s->ier & UART_IER_MSI) ? 1 : 0; |
| serial_update_msl(s); |
| |
| if (s->poll_msl >= 0 && !(s->mcr & UART_MCR_LOOP)) { |
| serial_update_tiocm(s); |
| } |
| |
| if (s->watch_tag > 0) { |
| g_source_remove(s->watch_tag); |
| s->watch_tag = qemu_chr_fe_add_watch(&s->chr, G_IO_OUT | G_IO_HUP, |
| serial_watch_cb, s); |
| } |
| |
| return 0; |
| } |
| |
| static void serial_realize(DeviceState *dev, Error **errp) |
| { |
| SerialState *s = SERIAL(dev); |
| |
| s->modem_status_poll = timer_new_ns(QEMU_CLOCK_VIRTUAL, (QEMUTimerCB *) serial_update_msl, s); |
| |
| s->fifo_timeout_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, (QEMUTimerCB *) fifo_timeout_int, s); |
| qemu_register_reset(serial_reset, s); |
| |
| qemu_chr_fe_set_handlers(&s->chr, serial_can_receive1, serial_receive1, |
| serial_event, serial_be_change, s, NULL, true); |
| fifo8_create(&s->recv_fifo, UART_FIFO_LENGTH); |
| fifo8_create(&s->xmit_fifo, UART_FIFO_LENGTH); |
| serial_reset(s); |
| } |
| |
| static void serial_unrealize(DeviceState *dev) |
| { |
| SerialState *s = SERIAL(dev); |
| |
| qemu_chr_fe_deinit(&s->chr, false); |
| |
| timer_free(s->modem_status_poll); |
| |
| timer_free(s->fifo_timeout_timer); |
| |
| fifo8_destroy(&s->recv_fifo); |
| fifo8_destroy(&s->xmit_fifo); |
| |
| qemu_unregister_reset(serial_reset, s); |
| } |
| |
| const MemoryRegionOps serial_io_ops = { |
| .read = serial_ioport_read, |
| .write = serial_ioport_write, |
| .valid = { |
| .unaligned = 1, |
| }, |
| .impl = { |
| .min_access_size = 1, |
| .max_access_size = 1, |
| }, |
| .endianness = DEVICE_LITTLE_ENDIAN, |
| }; |
| |
| static const Property serial_properties[] = { |
| DEFINE_PROP_CHR("chardev", SerialState, chr), |
| DEFINE_PROP_UINT32("baudbase", SerialState, baudbase, 115200), |
| DEFINE_PROP_BOOL("wakeup", SerialState, wakeup, false), |
| }; |
| |
| static void serial_class_init(ObjectClass *klass, void* data) |
| { |
| DeviceClass *dc = DEVICE_CLASS(klass); |
| |
| /* internal device for serialio/serialmm, not user-creatable */ |
| dc->user_creatable = false; |
| dc->realize = serial_realize; |
| dc->unrealize = serial_unrealize; |
| device_class_set_props(dc, serial_properties); |
| } |
| |
| static const TypeInfo serial_info = { |
| .name = TYPE_SERIAL, |
| .parent = TYPE_DEVICE, |
| .instance_size = sizeof(SerialState), |
| .class_init = serial_class_init, |
| }; |
| |
| static void serial_register_types(void) |
| { |
| type_register_static(&serial_info); |
| } |
| |
| type_init(serial_register_types) |
