nmigen_boards/dev/flash.py

   1 from nmigen.build import *
   2
   3
   4 __all__ = ["SPIFlashResources"]
   5
   6
   7 def SPIFlashResources(*args, cs, clk, mosi, miso, wp=None, hold=None, attrs=None):
   8     resources = []
   9
  10     io_all = []
  11     if attrs is not None:
  12         io_all.append(attrs)
  13     io_all.append(Subsignal("cs",  PinsN(cs, dir="o")))
  14     io_all.append(Subsignal("clk", Pins(clk, dir="o", assert_width=1)))
  15
  16     io_1x = list(io_all)
  17     io_1x.append(Subsignal("mosi", Pins(mosi, dir="o", assert_width=1)))
  18     io_1x.append(Subsignal("miso", Pins(miso, dir="i", assert_width=1)))
  19     if wp is not None and hold is not None:
  20         io_1x.append(Subsignal("wp",   PinsN(wp,   dir="o", assert_width=1)))
  21         io_1x.append(Subsignal("hold", PinsN(hold, dir="o", assert_width=1)))
  22     resources.append(Resource.family(*args, default_name="spi_flash", ios=io_1x,
  23                                      name_suffix="1x"))
  24
  25     io_2x = list(io_all)
  26     io_2x.append(Subsignal("dq", Pins(" ".join([mosi, miso]), dir="io",
  27                                       assert_width=2)))
  28     resources.append(Resource.family(*args, default_name="spi_flash", ios=io_2x,
  29                                      name_suffix="2x"))
  30
  31     if wp is not None and hold is not None:
  32         io_4x = list(io_all)
  33         io_4x.append(Subsignal("dq", Pins(" ".join([mosi, miso, wp, hold]), dir="io",
  34                                           assert_width=4)))
  35         resources.append(Resource.family(*args, default_name="spi_flash", ios=io_4x,
  36                                          name_suffix="4x"))
  37
  38     return resources