hw/timer/sun4v-rtc.c

   1 /*
   2  * QEMU sun4v Real Time Clock device
   3  *
   4  * The sun4v_rtc device (sun4v tod clock)
   5  *
   6  * Copyright (c) 2016 Artyom Tarasenko
   7  *
   8  * This code is licensed under the GNU GPL v3 or (at your option) any later
   9  * version.
  10  */
  11
  12 #include "qemu/osdep.h"
  13 #include "hw/hw.h"
  14 #include "hw/sysbus.h"
  15 #include "qemu/timer.h"
  16 #include "hw/timer/sun4v-rtc.h"
  17 #include "trace.h"
  18
  19
  20 #define TYPE_SUN4V_RTC "sun4v_rtc"
  21 #define SUN4V_RTC(obj) OBJECT_CHECK(Sun4vRtc, (obj), TYPE_SUN4V_RTC)
  22
  23 typedef struct Sun4vRtc {
  24     SysBusDevice parent_obj;
  25
  26     MemoryRegion iomem;
  27 } Sun4vRtc;
  28
  29 static uint64_t sun4v_rtc_read(void *opaque, hwaddr addr,
  30                                 unsigned size)
  31 {
  32     uint64_t val = get_clock_realtime() / NANOSECONDS_PER_SECOND;
  33     if (!(addr & 4ULL)) {
  34         /* accessing the high 32 bits */
  35         val >>= 32;
  36     }
  37     trace_sun4v_rtc_read(addr, val);
  38     return val;
  39 }
  40
  41 static void sun4v_rtc_write(void *opaque, hwaddr addr,
  42                              uint64_t val, unsigned size)
  43 {
  44     trace_sun4v_rtc_write(addr, val);
  45 }
  46
  47 static const MemoryRegionOps sun4v_rtc_ops = {
  48     .read = sun4v_rtc_read,
  49     .write = sun4v_rtc_write,
  50     .endianness = DEVICE_NATIVE_ENDIAN,
  51 };
  52
  53 void sun4v_rtc_init(hwaddr addr)
  54 {
  55     DeviceState *dev;
  56     SysBusDevice *s;
  57
  58     dev = qdev_create(NULL, TYPE_SUN4V_RTC);
  59     s = SYS_BUS_DEVICE(dev);
  60
  61     qdev_init_nofail(dev);
  62
  63     sysbus_mmio_map(s, 0, addr);
  64 }
  65
  66 static void sun4v_rtc_realize(DeviceState *dev, Error **errp)
  67 {
  68     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
  69     Sun4vRtc *s = SUN4V_RTC(dev);
  70
  71     memory_region_init_io(&s->iomem, OBJECT(s), &sun4v_rtc_ops, s,
  72                           "sun4v-rtc", 0x08ULL);
  73     sysbus_init_mmio(sbd, &s->iomem);
  74 }
  75
  76 static void sun4v_rtc_class_init(ObjectClass *klass, void *data)
  77 {
  78     DeviceClass *dc = DEVICE_CLASS(klass);
  79
  80     dc->realize = sun4v_rtc_realize;
  81 }
  82
  83 static const TypeInfo sun4v_rtc_info = {
  84     .name          = TYPE_SUN4V_RTC,
  85     .parent        = TYPE_SYS_BUS_DEVICE,
  86     .instance_size = sizeof(Sun4vRtc),
  87     .class_init    = sun4v_rtc_class_init,
  88 };
  89
  90 static void sun4v_rtc_register_types(void)
  91 {
  92     type_register_static(&sun4v_rtc_info);
  93 }
  94
  95 type_init(sun4v_rtc_register_types)