src/bsv/actual_pinmux.py

   1 from string import digits
   2 try:
   3     from string import maketrans
   4 except ImportError:
   5     maketrans = str.maketrans
   6
   7
   8 # ============== common bsv templates ============ #
   9 # first argument is the io-cell number being assigned.
  10 # second argument is the mux value.
  11 # Third argument is the signal from the pinmap file
  12 mux_wire = '''
  13       rule assign_{2}_on_cell{0}(wrcell{0}_mux=={1});
  14         {2}<=cell{0}_mux_in;
  15       endrule
  16 '''
  17 dedicated_wire = '''
  18       rule assign_{1}_on_cell{0};
  19         {1}<=cell{0}_mux_in;
  20       endrule
  21 '''
  22 # ============================================================
  23 digits = maketrans('0123456789', ' ' * 10)  # delete space later
  24
  25
  26 def cn(idx):  # idx is an integer
  27     return "cell%s_mux" % str(idx)
  28
  29
  30 def transfn(temp):
  31     """ removes the number from the string of signal name.
  32     """
  33     temp = temp.split('_')
  34     if len(temp) == 2:
  35         temp[0] = temp[0].translate(digits)
  36         temp[0] = temp[0] .replace(' ', '')
  37     return '_'.join(temp)
  38
  39 def fmt(cell):
  40     """ blank entries need to output a 0 to the pin (it could just as
  41         well be a 1 but we choose 0).  reason: blank entries in
  42         the pinmap.txt file indicate that there's nothing to choose
  43         from.  however the user may still set the muxer to that value,
  44         and rather than throw an exception we choose to output... zero.
  45     """
  46     return "%s_io" % cell if cell else '0'
  47
  48
  49 def mkcomment(p, cell):
  50     """ returns a comment string for the cell when muxed
  51     """
  52     return ""
  53
  54 def init(p, ifaces):
  55     """ generates the actual output pinmux for each io-cell.  blank lines
  56         need to output "0" to the iopad, if there is no entry in
  57         that column.
  58
  59         text is outputted in the format:
  60             x_out =
  61                 muxer_sel==0 ? a :
  62                 muxer_sel==1 ? b :
  63                 muxer_sel==2 ? 0 :
  64                 d
  65
  66         last line doesn't need selector-logic, obviously.
  67     """
  68     p.pinmux = ' '
  69     global dedicated_wire
  70     fmtstr = "\t\t\twr%s == %d ? %s :%s\n" # mux-selector format
  71     for cell in p.muxed_cells:
  72         p.pinmux += "      // output muxer for cell idx %s\n" % cell[0]
  73         p.pinmux += "      %s_out=\n" % cn(cell[0])
  74         for i in range(0, len(cell) - 2):
  75             comment = mkcomment(p, cell[i + 1])
  76             p.pinmux += fmtstr % (cn(cell[0]), i, fmt(cell[i + 1]), comment)
  77         comment = mkcomment(p, cell[i + 2])
  78         p.pinmux += "\t\t\t" + fmt(cell[i + 2]) + comment # last line
  79         p.pinmux += ";\n"
  80         # ======================================================== #
  81
  82         # check each cell if "peripheral input/inout" then assign its wire
  83         # Here we check the direction of each signal in the dictionary.
  84         # We choose to keep the dictionary within the code and not user-input
  85         # since the interfaces are always standard and cannot change from
  86         # user-to-user. Plus this also reduces human-error as well :)
  87         for i in range(0, len(cell) - 1):
  88             cname = cell[i + 1]
  89             if not cname: # skip blank entries, no need to test
  90                 continue
  91             temp = transfn(cname)
  92             x = ifaces.getifacetype(temp)
  93             #print (cname, temp, x)
  94             assert x is not None, "ERROR: The signal : " + \
  95                 str(cname) + \
  96                 " of pinmap.txt isn't present \nin the current" + \
  97                 " dictionary. Update dictionary or fix-typo."
  98             if x == "input":
  99                 p.pinmux += \
 100                     mux_wire.format(cell[0], i, "wr" + cname) + "\n"
 101             elif x == "inout":
 102                 p.pinmux += \
 103                     mux_wire.format(cell[0], i, "wr" + cname +
 104                                                 "_in") + "\n"
 105     # ============================================================ #
 106
 107     # ==================  Logic for dedicated pins ========= #
 108     for cell in p.dedicated_cells:
 109         p.pinmux += "      %s_out=%s_io;\n" % (cn(cell[0]), cell[1])
 110         temp = cell[1].translate(digits)
 111         x = ifaces.getifacetype(temp)
 112         if x == "input":
 113             pinmux = pinmux + \
 114                 dedicated_wire.format(cell[0], "wr" + cell[1]) + "\n"
 115         elif x == "inout":
 116             pinmux = pinmux + \
 117                 dedicated_wire.format(cell[0], "wr" + cell[1] + "_in") + "\n"
 118     # =======================================================#