diff options
Diffstat (limited to 'hw/syborg_timer.c')
| -rw-r--r-- | hw/syborg_timer.c | 235 |
1 files changed, 235 insertions, 0 deletions
diff --git a/hw/syborg_timer.c b/hw/syborg_timer.c new file mode 100644 index 0000000..a84ad86 --- /dev/null +++ b/hw/syborg_timer.c @@ -0,0 +1,235 @@ +/* + * Syborg Interval Timer. + * + * Copyright (c) 2008 CodeSourcery + * + * 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 "sysbus.h" +#include "qemu-timer.h" +#include "syborg.h" + +//#define DEBUG_SYBORG_TIMER + +#ifdef DEBUG_SYBORG_TIMER +#define DPRINTF(fmt, ...) \ +do { printf("syborg_timer: " fmt , ##args); } while (0) +#define BADF(fmt, ...) \ +do { fprintf(stderr, "syborg_timer: error: " fmt , ## __VA_ARGS__); \ + exit(1);} while (0) +#else +#define DPRINTF(fmt, ...) do {} while(0) +#define BADF(fmt, ...) \ +do { fprintf(stderr, "syborg_timer: error: " fmt , ## __VA_ARGS__);} while (0) +#endif + +enum { + TIMER_ID = 0, + TIMER_RUNNING = 1, + TIMER_ONESHOT = 2, + TIMER_LIMIT = 3, + TIMER_VALUE = 4, + TIMER_INT_ENABLE = 5, + TIMER_INT_STATUS = 6, + TIMER_FREQ = 7 +}; + +typedef struct { + SysBusDevice busdev; + ptimer_state *timer; + int running; + int oneshot; + uint32_t limit; + uint32_t freq; + uint32_t int_level; + uint32_t int_enabled; + qemu_irq irq; +} SyborgTimerState; + +static void syborg_timer_update(SyborgTimerState *s) +{ + /* Update interrupt. */ + if (s->int_level && s->int_enabled) { + qemu_irq_raise(s->irq); + } else { + qemu_irq_lower(s->irq); + } +} + +static void syborg_timer_tick(void *opaque) +{ + SyborgTimerState *s = (SyborgTimerState *)opaque; + //DPRINTF("Timer Tick\n"); + s->int_level = 1; + if (s->oneshot) + s->running = 0; + syborg_timer_update(s); +} + +static uint32_t syborg_timer_read(void *opaque, target_phys_addr_t offset) +{ + SyborgTimerState *s = (SyborgTimerState *)opaque; + + DPRINTF("Reg read %d\n", (int)offset); + offset &= 0xfff; + switch (offset >> 2) { + case TIMER_ID: + return SYBORG_ID_TIMER; + case TIMER_RUNNING: + return s->running; + case TIMER_ONESHOT: + return s->oneshot; + case TIMER_LIMIT: + return s->limit; + case TIMER_VALUE: + return ptimer_get_count(s->timer); + case TIMER_INT_ENABLE: + return s->int_enabled; + case TIMER_INT_STATUS: + return s->int_level; + case TIMER_FREQ: + return s->freq; + default: + cpu_abort(cpu_single_env, "syborg_timer_read: Bad offset %x\n", + (int)offset); + return 0; + } +} + +static void syborg_timer_write(void *opaque, target_phys_addr_t offset, + uint32_t value) +{ + SyborgTimerState *s = (SyborgTimerState *)opaque; + + DPRINTF("Reg write %d\n", (int)offset); + offset &= 0xfff; + switch (offset >> 2) { + case TIMER_RUNNING: + if (value == s->running) + break; + s->running = value; + if (value) { + ptimer_run(s->timer, s->oneshot); + } else { + ptimer_stop(s->timer); + } + break; + case TIMER_ONESHOT: + if (s->running) { + ptimer_stop(s->timer); + } + s->oneshot = value; + if (s->running) { + ptimer_run(s->timer, s->oneshot); + } + break; + case TIMER_LIMIT: + s->limit = value; + ptimer_set_limit(s->timer, value, 1); + break; + case TIMER_VALUE: + ptimer_set_count(s->timer, value); + break; + case TIMER_INT_ENABLE: + s->int_enabled = value; + syborg_timer_update(s); + break; + case TIMER_INT_STATUS: + s->int_level &= ~value; + syborg_timer_update(s); + break; + default: + cpu_abort(cpu_single_env, "syborg_timer_write: Bad offset %x\n", + (int)offset); + break; + } +} + +static CPUReadMemoryFunc *syborg_timer_readfn[] = { + syborg_timer_read, + syborg_timer_read, + syborg_timer_read +}; + +static CPUWriteMemoryFunc *syborg_timer_writefn[] = { + syborg_timer_write, + syborg_timer_write, + syborg_timer_write +}; + +static void syborg_timer_save(QEMUFile *f, void *opaque) +{ + SyborgTimerState *s = opaque; + + qemu_put_be32(f, s->running); + qemu_put_be32(f, s->oneshot); + qemu_put_be32(f, s->limit); + qemu_put_be32(f, s->int_level); + qemu_put_be32(f, s->int_enabled); + qemu_put_ptimer(f, s->timer); +} + +static int syborg_timer_load(QEMUFile *f, void *opaque, int version_id) +{ + SyborgTimerState *s = opaque; + + if (version_id != 1) + return -EINVAL; + + s->running = qemu_get_be32(f); + s->oneshot = qemu_get_be32(f); + s->limit = qemu_get_be32(f); + s->int_level = qemu_get_be32(f); + s->int_enabled = qemu_get_be32(f); + qemu_get_ptimer(f, s->timer); + + return 0; +} + +static void syborg_timer_init(SysBusDevice *dev) +{ + SyborgTimerState *s = FROM_SYSBUS(SyborgTimerState, dev); + QEMUBH *bh; + int iomemtype; + + s->freq = qdev_get_prop_int(&dev->qdev, "frequency", 0); + if (s->freq == 0) { + fprintf(stderr, "syborg_timer: Zero/unset frequency\n"); + exit(1); + } + sysbus_init_irq(dev, &s->irq); + iomemtype = cpu_register_io_memory(0, syborg_timer_readfn, + syborg_timer_writefn, s); + sysbus_init_mmio(dev, 0x1000, iomemtype); + + bh = qemu_bh_new(syborg_timer_tick, s); + s->timer = ptimer_init(bh); + ptimer_set_freq(s->timer, s->freq); + register_savevm("syborg_timer", -1, 1, + syborg_timer_save, syborg_timer_load, s); +} + +static void syborg_timer_register_devices(void) +{ + sysbus_register_dev("syborg,timer", sizeof(SyborgTimerState), + syborg_timer_init); +} + +device_init(syborg_timer_register_devices) |