diff options
Diffstat (limited to 'hw/syborg_rtc.c')
| -rw-r--r-- | hw/syborg_rtc.c | 147 |
1 files changed, 147 insertions, 0 deletions
diff --git a/hw/syborg_rtc.c b/hw/syborg_rtc.c new file mode 100644 index 0000000..b480d53 --- /dev/null +++ b/hw/syborg_rtc.c @@ -0,0 +1,147 @@ +/* + * Syborg RTC + * + * 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" + +enum { + RTC_ID = 0, + RTC_LATCH = 1, + RTC_DATA_LOW = 2, + RTC_DATA_HIGH = 3 +}; + +typedef struct { + SysBusDevice busdev; + int64_t offset; + int64_t data; + qemu_irq irq; +} SyborgRTCState; + +static uint32_t syborg_rtc_read(void *opaque, target_phys_addr_t offset) +{ + SyborgRTCState *s = (SyborgRTCState *)opaque; + offset &= 0xfff; + switch (offset >> 2) { + case RTC_ID: + return SYBORG_ID_RTC; + case RTC_DATA_LOW: + return (uint32_t)s->data; + case RTC_DATA_HIGH: + return (uint32_t)(s->data >> 32); + default: + cpu_abort(cpu_single_env, "syborg_rtc_read: Bad offset %x\n", + (int)offset); + return 0; + } +} + +static void syborg_rtc_write(void *opaque, target_phys_addr_t offset, uint32_t value) +{ + SyborgRTCState *s = (SyborgRTCState *)opaque; + uint64_t now; + + offset &= 0xfff; + switch (offset >> 2) { + case RTC_LATCH: + now = qemu_get_clock(vm_clock); + if (value >= 4) { + s->offset = s->data - now; + } else { + s->data = now + s->offset; + while (value) { + s->data /= 1000; + value--; + } + } + break; + case RTC_DATA_LOW: + s->data = (s->data & ~(uint64_t)0xffffffffu) | value; + break; + case RTC_DATA_HIGH: + s->data = (s->data & 0xffffffffu) | ((uint64_t)value << 32); + break; + default: + cpu_abort(cpu_single_env, "syborg_rtc_write: Bad offset %x\n", + (int)offset); + break; + } +} + +static CPUReadMemoryFunc *syborg_rtc_readfn[] = { + syborg_rtc_read, + syborg_rtc_read, + syborg_rtc_read +}; + +static CPUWriteMemoryFunc *syborg_rtc_writefn[] = { + syborg_rtc_write, + syborg_rtc_write, + syborg_rtc_write +}; + +static void syborg_rtc_save(QEMUFile *f, void *opaque) +{ + SyborgRTCState *s = opaque; + + qemu_put_be64(f, s->offset); + qemu_put_be64(f, s->data); +} + +static int syborg_rtc_load(QEMUFile *f, void *opaque, int version_id) +{ + SyborgRTCState *s = opaque; + + if (version_id != 1) + return -EINVAL; + + s->offset = qemu_get_be64(f); + s->data = qemu_get_be64(f); + + return 0; +} + +static void syborg_rtc_init(SysBusDevice *dev) +{ + SyborgRTCState *s = FROM_SYSBUS(SyborgRTCState, dev); + struct tm tm; + int iomemtype; + + iomemtype = cpu_register_io_memory(0, syborg_rtc_readfn, + syborg_rtc_writefn, s); + sysbus_init_mmio(dev, 0x1000, iomemtype); + + qemu_get_timedate(&tm, 0); + s->offset = (uint64_t)mktime(&tm) * 1000000000; + + register_savevm("syborg_rtc", -1, 1, syborg_rtc_save, syborg_rtc_load, s); +} + +static void syborg_rtc_register_devices(void) +{ + sysbus_register_dev("syborg,rtc", sizeof(SyborgRTCState), syborg_rtc_init); +} + +device_init(syborg_rtc_register_devices) |