src/soc/config/pinouts.py

   1 import os
   2 import sys
   3 import json
   4 from pprint import pprint
   5 from collections import OrderedDict
   6
   7
   8 def _byteify(data, ignore_dicts = False):
   9     # if this is a unicode string, return its string representation
  10     try:
  11         if isinstance(data, unicode):
  12             return data.encode('utf-8')
  13     except NameError:
  14         return data
  15     # if this is a list of values, return list of byteified values
  16     if isinstance(data, list):
  17         return [ _byteify(item, ignore_dicts=True) for item in data ]
  18     # if this is a dictionary, return dictionary of byteified keys and values
  19     # but only if we haven't already byteified it
  20     if isinstance(data, dict) and not ignore_dicts:
  21         return OrderedDict((_byteify(key, ignore_dicts=True),
  22                     _byteify(value, ignore_dicts=True))
  23                         for key, value in data.iteritems())
  24     # if it's anything else, return it in its original form
  25     return data
  26
  27
  28 def get_pinspecs(chipname=None, subset=None):
  29     """get_pinspecs - returns a dictionary of lists of pins for an IO function
  30     example: {'uart': ['tx+', 'rx-'],
  31              'i2c': ['sda*', 'scl+']}
  32     """
  33     chip = load_pinouts(chipname)
  34     pinmap = chip['pins.map']
  35     specs = OrderedDict() # preserve order
  36     for k, bus in chip['pins.specs'].items():
  37         k, num = k.lower().split(":")
  38         name = '%s%s' % (k, num)
  39         if subset is None or name in subset:
  40             pins = []
  41             for pin in bus:
  42                 pin = pin.lower()
  43                 pname = '%s_%s' % (name, pin[:-1])
  44                 if pname in pinmap:
  45                     newpin = pinmap[pname][2:]
  46                     newpin = '_'.join(newpin.split("_")[1:])
  47                     pin = newpin + pin[-1]
  48                 pins.append(pin)
  49             specs['%s%s' % (k, num)] = pins
  50     return specs
  51
  52
  53 def load_pinouts(chipname=None):
  54     """load_pinouts - loads the JSON-formatted dictionary of a chip spec
  55
  56     note: this works only when pinmux is a correctly-initialised git submodule
  57     and when the spec has been actually generated.  see Makefile "make mkpinmux"
  58     """
  59
  60     # default pinouts for now: ls180
  61     if chipname is None:
  62         chipname = 'ls180'
  63
  64     # load JSON-formatted pad info from pinmux
  65     pth = os.path.abspath(__file__)
  66     pth = os.path.split(pth)[0]
  67
  68     # path is relative to this filename, in the pinmux submodule
  69     pinmux = os.getenv("PINMUX", "%s/../../../pinmux" % pth)
  70     fname = "%s/%s/litex_pinpads.json" % (pinmux, chipname)
  71     with open(fname) as f:
  72         txt = f.read()
  73
  74     # decode the json, strip unicode formatting (has to be recursive)
  75     chip = json.loads(txt, object_hook=_byteify)
  76     chip = _byteify(chip, ignore_dicts=True)
  77
  78     return chip
  79
  80 if __name__ == '__main__':
  81     if sys.argv == 2:
  82         chipname = sys.argv[1]
  83     else:
  84         chipname = None
  85     chip = load_pinouts(chipname)
  86     for k, v in chip.items():
  87         print ("\n****", k, "****")
  88         pprint(v)