hw/rtc/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/sysbus.h"
  14 #include "qapi/error.h"
  15 #include "qemu/module.h"
  16 #include "qemu/timer.h"
  17 #include "hw/rtc/sun4v-rtc.h"
  18 #include "trace.h"
  19 #include "qom/object.h"
  20
  21
  22 #define TYPE_SUN4V_RTC "sun4v_rtc"
  23 typedef struct Sun4vRtc Sun4vRtc;
  24 DECLARE_INSTANCE_CHECKER(Sun4vRtc, SUN4V_RTC,
  25                          TYPE_SUN4V_RTC)
  26
  27 struct Sun4vRtc {
  28     SysBusDevice parent_obj;
  29
  30     MemoryRegion iomem;
  31 };
  32
  33 static uint64_t sun4v_rtc_read(void *opaque, hwaddr addr,
  34                                 unsigned size)
  35 {
  36     uint64_t val = get_clock_realtime() / NANOSECONDS_PER_SECOND;
  37     if (!(addr & 4ULL)) {
  38         /* accessing the high 32 bits */
  39         val >>= 32;
  40     }
  41     trace_sun4v_rtc_read(addr, val);
  42     return val;
  43 }
  44
  45 static void sun4v_rtc_write(void *opaque, hwaddr addr,
  46                              uint64_t val, unsigned size)
  47 {
  48     trace_sun4v_rtc_write(addr, val);
  49 }
  50
  51 static const MemoryRegionOps sun4v_rtc_ops = {
  52     .read = sun4v_rtc_read,
  53     .write = sun4v_rtc_write,
  54     .endianness = DEVICE_NATIVE_ENDIAN,
  55 };
  56
  57 void sun4v_rtc_init(hwaddr addr)
  58 {
  59     DeviceState *dev;
  60     SysBusDevice *s;
  61
  62     dev = qdev_new(TYPE_SUN4V_RTC);
  63     s = SYS_BUS_DEVICE(dev);
  64
  65     sysbus_realize_and_unref(s, &error_fatal);
  66
  67     sysbus_mmio_map(s, 0, addr);
  68 }
  69
  70 static void sun4v_rtc_realize(DeviceState *dev, Error **errp)
  71 {
  72     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
  73     Sun4vRtc *s = SUN4V_RTC(dev);
  74
  75     memory_region_init_io(&s->iomem, OBJECT(s), &sun4v_rtc_ops, s,
  76                           "sun4v-rtc", 0x08ULL);
  77     sysbus_init_mmio(sbd, &s->iomem);
  78 }
  79
  80 static void sun4v_rtc_class_init(ObjectClass *klass, void *data)
  81 {
  82     DeviceClass *dc = DEVICE_CLASS(klass);
  83
  84     dc->realize = sun4v_rtc_realize;
  85 }
  86
  87 static const TypeInfo sun4v_rtc_info = {
  88     .name          = TYPE_SUN4V_RTC,
  89     .parent        = TYPE_SYS_BUS_DEVICE,
  90     .instance_size = sizeof(Sun4vRtc),
  91     .class_init    = sun4v_rtc_class_init,
  92 };
  93
  94 static void sun4v_rtc_register_types(void)
  95 {
  96     type_register_static(&sun4v_rtc_info);
  97 }
  98
  99 type_init(sun4v_rtc_register_types)