litex/soc/tools/remote/comm_pcie.py

   1 import mmap
   2
   3
   4 class CommPCIe:
   5     def __init__(self, bar, bar_size, debug=False):
   6         self.bar = bar
   7         self.bar_size = bar_size
   8         self.debug = debug
   9
  10     def open(self):
  11         if hasattr(self, "sysfs"):
  12             return
  13         self.sysfs = open(self.bar, "r+b")
  14         self.sysfs.flush()
  15         self.mmap = mmap.mmap(self.sysfs.fileno(), self.bar_size)
  16
  17     def close(self):
  18         if not hasattr(self, "sysfs"):
  19             return
  20         self.mmap.close()
  21         del self.mmap
  22         self.sysfs.close()
  23         del self.sysfs
  24
  25     def read(self, addr, length=None):
  26         data = []
  27         length_int = 1 if length is None else length
  28         for i in range(length_int):
  29             self.mmap.seek(addr + 4*i)
  30             value = int.from_bytes(self.mmap.read(4), "big")
  31             if self.debug:
  32                 print("read {:08x} @ {:08x}".format(value, addr + 4*i))
  33             if length is None:
  34                 return value
  35             data.append(value)
  36         return data
  37
  38     def write(self, addr, data):
  39         data = data if isinstance(data, list) else [data]
  40         length = len(data)
  41         for i, value in enumerate(data):
  42             self.mmap[addr + 4*i:addr + 4*(i + 1)] = value.to_bytes(4, byteorder="big")
  43             if self.debug:
  44                 print("write {:08x} @ {:08x}".format(value, addr + 4*i))