diff options
author | bellard <bellard@c046a42c-6fe2-441c-8c8c-71466251a162> | 2004-03-14 12:20:30 +0000 |
---|---|---|
committer | bellard <bellard@c046a42c-6fe2-441c-8c8c-71466251a162> | 2004-03-14 12:20:30 +0000 |
commit | 80cabfad16384ca47f783a7c494bd1c3c6e3c4bc (patch) | |
tree | ad2965750e60527e38280de84ab1d6d01d33ef68 /hw/serial.c | |
parent | 38ca2abc2eb0fc8edd067420b3fcfa10ffa0054b (diff) |
separated more devices from emulator
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@656 c046a42c-6fe2-441c-8c8c-71466251a162
Diffstat (limited to 'hw/serial.c')
-rw-r--r-- | hw/serial.c | 281 |
1 files changed, 281 insertions, 0 deletions
diff --git a/hw/serial.c b/hw/serial.c new file mode 100644 index 0000000000..e1225ec403 --- /dev/null +++ b/hw/serial.c @@ -0,0 +1,281 @@ +/* + * QEMU 16450 UART emulation + * + * Copyright (c) 2003-2004 Fabrice Bellard + * + * 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 <stdlib.h> +#include <stdio.h> +#include <stdarg.h> +#include <string.h> +#include <getopt.h> +#include <inttypes.h> +#include <unistd.h> +#include <sys/mman.h> +#include <fcntl.h> +#include <signal.h> +#include <time.h> +#include <sys/time.h> +#include <malloc.h> +#include <termios.h> +#include <sys/poll.h> +#include <errno.h> +#include <sys/wait.h> +#include <netinet/in.h> + +#include "cpu.h" +#include "vl.h" + +//#define DEBUG_SERIAL + +#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 */ + +/* + * 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 */ + +typedef struct SerialState { + uint8_t divider; + uint8_t rbr; /* receive register */ + uint8_t ier; + uint8_t iir; /* read only */ + uint8_t lcr; + uint8_t mcr; + uint8_t lsr; /* read only */ + uint8_t msr; + uint8_t scr; + /* NOTE: this hidden state is necessary for tx irq generation as + it can be reset while reading iir */ + int thr_ipending; + int irq; +} SerialState; + +SerialState serial_ports[1]; + +void serial_update_irq(void) +{ + SerialState *s = &serial_ports[0]; + + if ((s->lsr & UART_LSR_DR) && (s->ier & UART_IER_RDI)) { + s->iir = UART_IIR_RDI; + } else if (s->thr_ipending && (s->ier & UART_IER_THRI)) { + s->iir = UART_IIR_THRI; + } else { + s->iir = UART_IIR_NO_INT; + } + if (s->iir != UART_IIR_NO_INT) { + pic_set_irq(s->irq, 1); + } else { + pic_set_irq(s->irq, 0); + } +} + +void serial_ioport_write(CPUState *env, uint32_t addr, uint32_t val) +{ + SerialState *s = &serial_ports[0]; + unsigned char ch; + int ret; + + addr &= 7; +#ifdef DEBUG_SERIAL + printf("serial: write addr=0x%02x val=0x%02x\n", addr, val); +#endif + switch(addr) { + default: + case 0: + if (s->lcr & UART_LCR_DLAB) { + s->divider = (s->divider & 0xff00) | val; + } else { + s->thr_ipending = 0; + s->lsr &= ~UART_LSR_THRE; + serial_update_irq(); + + ch = val; + do { + ret = write(1, &ch, 1); + } while (ret != 1); + s->thr_ipending = 1; + s->lsr |= UART_LSR_THRE; + s->lsr |= UART_LSR_TEMT; + serial_update_irq(); + } + break; + case 1: + if (s->lcr & UART_LCR_DLAB) { + s->divider = (s->divider & 0x00ff) | (val << 8); + } else { + s->ier = val; + serial_update_irq(); + } + break; + case 2: + break; + case 3: + s->lcr = val; + break; + case 4: + s->mcr = val; + break; + case 5: + break; + case 6: + s->msr = val; + break; + case 7: + s->scr = val; + break; + } +} + +uint32_t serial_ioport_read(CPUState *env, uint32_t addr) +{ + SerialState *s = &serial_ports[0]; + uint32_t ret; + + addr &= 7; + switch(addr) { + default: + case 0: + if (s->lcr & UART_LCR_DLAB) { + ret = s->divider & 0xff; + } else { + ret = s->rbr; + s->lsr &= ~(UART_LSR_DR | UART_LSR_BI); + serial_update_irq(); + } + break; + case 1: + if (s->lcr & UART_LCR_DLAB) { + ret = (s->divider >> 8) & 0xff; + } else { + ret = s->ier; + } + break; + case 2: + ret = s->iir; + /* reset THR pending bit */ + if ((ret & 0x7) == UART_IIR_THRI) + s->thr_ipending = 0; + serial_update_irq(); + break; + case 3: + ret = s->lcr; + break; + case 4: + ret = s->mcr; + break; + case 5: + ret = s->lsr; + 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 { + ret = s->msr; + } + break; + case 7: + ret = s->scr; + break; + } +#ifdef DEBUG_SERIAL + printf("serial: read addr=0x%02x val=0x%02x\n", addr, ret); +#endif + return ret; +} + +int serial_can_receive(void) +{ + SerialState *s = &serial_ports[0]; + return !(s->lsr & UART_LSR_DR); +} + +void serial_receive_byte(int ch) +{ + SerialState *s = &serial_ports[0]; + + s->rbr = ch; + s->lsr |= UART_LSR_DR; + serial_update_irq(); +} + +void serial_receive_break(void) +{ + SerialState *s = &serial_ports[0]; + + s->rbr = 0; + s->lsr |= UART_LSR_BI | UART_LSR_DR; + serial_update_irq(); +} + +void serial_init(int base, int irq) +{ + SerialState *s = &serial_ports[0]; + + s->irq = irq; + s->lsr = UART_LSR_TEMT | UART_LSR_THRE; + s->iir = UART_IIR_NO_INT; + + register_ioport_write(base, 8, serial_ioport_write, 1); + register_ioport_read(base, 8, serial_ioport_read, 1); +} |