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