diff options
Diffstat (limited to 'hw/parallel.c')
| -rw-r--r-- | hw/parallel.c | 188 |
1 files changed, 188 insertions, 0 deletions
diff --git a/hw/parallel.c b/hw/parallel.c new file mode 100644 index 0000000000..1b9fe7cef5 --- /dev/null +++ b/hw/parallel.c @@ -0,0 +1,188 @@ +/* + * QEMU Parallel PORT 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 "vl.h" + +//#define DEBUG_PARALLEL + +/* + * These are the definitions for the Printer Status Register + */ +#define PARA_STS_BUSY 0x80 /* Busy complement */ +#define PARA_STS_ACK 0x40 /* Acknowledge */ +#define PARA_STS_PAPER 0x20 /* Out of paper */ +#define PARA_STS_ONLINE 0x10 /* Online */ +#define PARA_STS_ERROR 0x08 /* Error complement */ + +/* + * These are the definitions for the Printer Control Register + */ +#define PARA_CTR_INTEN 0x10 /* IRQ Enable */ +#define PARA_CTR_SELECT 0x08 /* Select In complement */ +#define PARA_CTR_INIT 0x04 /* Initialize Printer complement */ +#define PARA_CTR_AUTOLF 0x02 /* Auto linefeed complement */ +#define PARA_CTR_STROBE 0x01 /* Strobe complement */ + +struct ParallelState { + uint8_t data; + uint8_t status; /* read only register */ + uint8_t control; + int irq; + int irq_pending; + CharDriverState *chr; +}; + +static void parallel_update_irq(ParallelState *s) +{ + if (s->irq_pending) + pic_set_irq(s->irq, 1); + else + pic_set_irq(s->irq, 0); +} + +static void parallel_ioport_write(void *opaque, uint32_t addr, uint32_t val) +{ + ParallelState *s = opaque; + + addr &= 7; +#ifdef DEBUG_PARALLEL + printf("parallel: write addr=0x%02x val=0x%02x\n", addr, val); +#endif + switch(addr) { + case 0: + s->data = val; + parallel_update_irq(s); + break; + case 2: + if ((val & PARA_CTR_INIT) == 0 ) { + s->status = PARA_STS_BUSY; + s->status |= PARA_STS_ACK; + s->status |= PARA_STS_ONLINE; + s->status |= PARA_STS_ERROR; + } + else if (val & PARA_CTR_SELECT) { + if (val & PARA_CTR_STROBE) { + s->status &= ~PARA_STS_BUSY; + if ((s->control & PARA_CTR_STROBE) == 0) + qemu_chr_write(s->chr, &s->data, 1); + } else { + if (s->control & PARA_CTR_INTEN) { + s->irq_pending = 1; + } + } + } + parallel_update_irq(s); + s->control = val; + break; + } +} + +static uint32_t parallel_ioport_read(void *opaque, uint32_t addr) +{ + ParallelState *s = opaque; + uint32_t ret = 0xff; + + addr &= 7; + switch(addr) { + case 0: + ret = s->data; + break; + case 1: + ret = s->status; + s->irq_pending = 0; + if ((s->status & PARA_STS_BUSY) == 0 && (s->control & PARA_CTR_STROBE) == 0) { + /* XXX Fixme: wait 5 microseconds */ + if (s->status & PARA_STS_ACK) + s->status &= ~PARA_STS_ACK; + else { + /* XXX Fixme: wait 5 microseconds */ + s->status |= PARA_STS_ACK; + s->status |= PARA_STS_BUSY; + } + } + parallel_update_irq(s); + break; + case 2: + ret = s->control; + break; + } +#ifdef DEBUG_PARALLEL + printf("parallel: read addr=0x%02x val=0x%02x\n", addr, ret); +#endif + return ret; +} + +static int parallel_can_receive(ParallelState *s) +{ + return 0; +} + +static void parallel_receive_byte(ParallelState *s, int ch) +{ +} + +static void parallel_receive_break(ParallelState *s) +{ +} + +static int parallel_can_receive1(void *opaque) +{ + ParallelState *s = opaque; + return parallel_can_receive(s); +} + +static void parallel_receive1(void *opaque, const uint8_t *buf, int size) +{ + ParallelState *s = opaque; + parallel_receive_byte(s, buf[0]); +} + +static void parallel_event(void *opaque, int event) +{ + ParallelState *s = opaque; +} + +/* If fd is zero, it means that the parallel device uses the console */ +ParallelState *parallel_init(int base, int irq, CharDriverState *chr) +{ + ParallelState *s; + + s = qemu_mallocz(sizeof(ParallelState)); + if (!s) + return NULL; + s->irq = irq; + s->data = 0; + s->status = PARA_STS_BUSY; + s->status |= PARA_STS_ACK; + s->status |= PARA_STS_ONLINE; + s->status |= PARA_STS_ERROR; + s->control = PARA_CTR_SELECT; + s->control |= PARA_CTR_INIT; + + register_ioport_write(base, 8, 1, parallel_ioport_write, s); + register_ioport_read(base, 8, 1, parallel_ioport_read, s); + s->chr = chr; + qemu_chr_add_read_handler(chr, parallel_can_receive1, parallel_receive1, s); + qemu_chr_add_event_handler(chr, parallel_event); + return s; +} |