src/actual_pinmux.py

   1 from params import *
   2 from string import digits
   3
   4
   5 # dictionary of properties of signals that are supported.
   6 dictionary = {
   7     "uart_rx"   : "input",
   8     "uart_tx"   : "output",
   9     "spi_sclk"  : "output",
  10     "spi_mosi"  : "output",
  11     "spi_ss"            : "output",
  12     "spi_miso"  : "input",
  13     "twi_sda"   : "inout",
  14     "twi_scl"   : "inout"
  15 }
  16
  17
  18 # ============== common bsv templates ============ #
  19 assign_cell = '''cell{0}_out=wrmux{0}=={1}?'''
  20 # first argument is the io-cell number being assigned.
  21 # second argument is the mux value.
  22 # Third argument is the signal from the pinmap file
  23 input_wire = '''
  24       rule assign_{2}_on_cell{0}(wrmux{0}=={1});
  25         {2}<=cell{0}_in;
  26       endrule
  27 '''
  28 # ============================================================
  29 pinmux = ''' '''
  30 pinmap_file = open("./pinmap.txt", "r")
  31 dedicated = False
  32 for lineno, line in enumerate(pinmap_file):
  33     line1 = line.split()
  34     if("muxed" in line):
  35         dedicated = False
  36     elif("dedicated" in line):
  37         dedicated = True
  38     # ==== Logic for muxed pins ==== #
  39     if(len(line1) > 1 and not(dedicated)):
  40         if(lineno > N_IO):
  41             print(
  42                 "ERROR: Parameter N_IO(" +
  43                 str(N_IO) +
  44                 ") is less than the pin number in line: " +
  45                 str(lineno) +
  46                 " of pinmap.txt")
  47             exit(1)
  48         # ==== Mux each generic IO cell with the mapping ===== #
  49         # provided in the pinmap file
  50         pinmux = pinmux + "             cell" + str(line1[0]) + "_out="
  51         i = 0
  52         while(i < len(line1) - 1):
  53             pinmux = pinmux + "wrmux" + \
  54                 str(line1[0]) + "==" + str(i) + "?" + line1[i + 1] + "_io:"
  55             if(i + 2 == len(line1) - 1):
  56                 pinmux = pinmux + line1[i + 2] + "_io"
  57                 i = i + 2
  58             else:
  59                 i = i + 1
  60         pinmux = pinmux + ";\n"
  61         # ======================================================== #
  62
  63         # check each cell if "peripheral input/inout" then assign its wire
  64         # Here we check the direction of each signal in the dictionary.
  65         # We choose to keep the dictionary within the code and not user-input
  66         # since the interfaces are always standard and cannot change from
  67         # user-to-user. Plus this also reduces human-error as well :)
  68         for i in range(0, len(line1) - 1):
  69             digits = str.maketrans(dict.fromkeys('0123456789'))
  70             temp = line1[i + 1].translate(digits)
  71             x = dictionary.get(temp)
  72             if(x is None):
  73                 print(
  74                     "Error: The signal : " +
  75                     str(line1[i + 1]) +
  76                     " in lineno: " +
  77                     str(lineno) + "of pinmap.txt isn't present in the \
  78                     current dictionary.\nUpdate dictionary or fix-typo.")
  79                 exit(1)
  80             if(x == "input"):
  81                 pinmux = pinmux + \
  82                     input_wire.format(line1[0], i, "wr" + line1[i + 1]) + "\n"
  83             elif(x == "inout"):
  84                 pinmux = pinmux + \
  85                     input_wire.format(line1[0], i, "wr" + line1[i + 1] +
  86                                       "_in") + "\n"
  87         # ============================================================ #
  88
  89     # ==================  Logic for dedicated pins ========= #
  90     elif(len(line1) > 1 and dedicated):
  91         pinmux = pinmux + "             cell" + \
  92             str(line1[0]) + "_out=" + line1[1] + "_io;\n"
  93     # ======================================================= #
  94 # =========================================================