1 import qemu

     2 

     3 class syborg_timer(qemu.devclass):

     4   REG_ID            = 0

     5   REG_LATCH         = 1

     6   REG_DATA_LOW      = 2

     7   REG_DATA_HIGH     = 3

     8 

     9   def create(self):

    10     self.data = 0

    11     self.offset = qemu.start_time() * 1000000 - qemu.get_clock()

    12 

    13   def read_reg(self, offset):

    14     offset >>= 2

    15     if offset == self.REG_ID:

    16       return 0xc51d0004

    17     elif offset == self.REG_DATA_LOW:

    18       return self.data & 0xffffffff

    19     elif offset == self.REG_DATA_HIGH:

    20       return (self.data >> 32) & 0xffffffff

    21     return 0

    22 

    23   def write_reg(self, offset, value):

    24     offset >>= 2

    25     if offset == self.REG_LATCH:

    26       now = qemu.get_clock()

    27       if value >= 4:

    28         self.offset = self.data - now

    29       else:

    30         self.data = now + self.offset

    31         while value:

    32           self.data /= 1000

    33           value -= 1;

    34     elif offset == self.REG_DATA_LOW:

    35       self.data = (self.data & ~0xffffffff) | value

    36     elif offset == self.REG_DATA_HIGH:

    37       self.data = (self.data & 0xffffffff) | (value << 32)

    38 

    39   def save(self, f):

    40     f.put_s64(self.offset)

    41     f.put_u64(self.data)

    42 

    43   def load(self, f):

    44     self.offset = f.get_s64()

    45     self.data = f.get_u64()

    46 

    47   # Device class properties

    48   regions = [qemu.ioregion(0x1000, readl=read_reg, writel=write_reg)]

    49   irqs = 0

    50   name = "syborg,rtc"

    51   properties = {}

    52 

    53 qemu.register_device(syborg_timer)