src/bsv/pinmux_generator.py

   1 # ================================== Steps to add peripherals ============
   2 # Step-1:   create interface declaration for the peripheral to be added.
   3 #           Remember these are interfaces defined for the pinmux and hence
   4 #           will be opposite to those defined at the peripheral.
   5 #           For eg. the output TX from the UART will be input (method Action)
   6 #           for the pinmux.
   7 #           These changes will have to be done in interface_decl.py
   8 # Step-2    define the wires that will be required to transfer data from the
   9 #           peripheral interface to the IO cell and vice-versa. Create a
  10 #           mkDWire for each input/output between the peripheral and the
  11 #           pinmux. Also create an implicit wire of GenericIOType for each cell
  12 #           that can be connected to a each bit from the peripheral.
  13 #           These changes will have to be done in wire_def.py
  14 # Step-3:   create the definitions for each of the methods defined above.
  15 #           These changes will have to be done in interface_decl.py
  16 # ========================================================================
  17
  18 # default module imports
  19 import os
  20 import os.path
  21 import time
  22 import math
  23
  24 # project module imports
  25 from bsv.interface_decl import Interfaces, mux_interface, io_interface
  26 from parse import Parse
  27 from bsv.actual_pinmux import init
  28 from bsv.bus_transactors import axi4_lite
  29
  30 copyright = '''
  31 /*
  32    This BSV file has been generated by the PinMux tool available at:
  33    https://bitbucket.org/casl/pinmux.
  34
  35    Authors: Neel Gala, Luke
  36    Date of generation: ''' + time.strftime("%c") + '''
  37 */
  38 '''
  39 header = copyright + '''
  40 package pinmux;
  41
  42    typedef struct{
  43       Bit#(1) outputval;      // output from core to pad                bit7
  44       Bit#(1) output_en;      // output enable from core to pad         bit6
  45       Bit#(1) input_en;       // input enable from core to io_cell      bit5
  46       Bit#(1) pullup_en;      // pullup enable from core to io_cell     bit4
  47       Bit#(1) pulldown_en;    // pulldown enable from core to io_cell   bit3
  48       Bit#(1) drivestrength;  // drivestrength from core to io_cell     bit2
  49       Bit#(1) pushpull_en;    // pushpull enable from core to io_cell   bit1
  50       Bit#(1) opendrain_en;   // opendrain enable form core to io_cell  bit0
  51    } GenericIOType deriving(Eq,Bits,FShow);
  52
  53 '''
  54 footer = '''
  55      endinterface;
  56    endmodule
  57 endpackage
  58 '''
  59
  60
  61 def pinmuxgen(pth=None, verify=True):
  62     """ populating the file with the code
  63     """
  64
  65     p = Parse(pth, verify)
  66     ifaces = Interfaces(pth)
  67     ifaces.ifaceadd('io', p.N_IO, io_interface, 0)
  68     init(p, ifaces)
  69
  70     bp = 'bsv_src'
  71     if pth:
  72         bp = os.path.join(pth, bp)
  73     if not os.path.exists(bp):
  74         os.makedirs(bp)
  75
  76     pmp = os.path.join(bp, 'pinmux.bsv')
  77     ptp = os.path.join(bp, 'PinTop.bsv')
  78     bvp = os.path.join(bp, 'bus.bsv')
  79
  80     write_pmp(pmp, p, ifaces)
  81     write_ptp(pmp, p, ifaces)
  82     write_bvp(pmp, p, ifaces)
  83
  84
  85 def write_pmp(pmp, p, ifaces):
  86     # package and interface declaration followed by
  87     # the generic io_cell definition
  88     with open(pmp, "w") as bsv_file:
  89         bsv_file.write(header)
  90
  91         bsv_file.write('''\
  92    interface MuxSelectionLines;
  93
  94       // declare the method which will capture the user pin-mux
  95       // selection values.The width of the input is dependent on the number
  96       // of muxes happening per IO. For now we have a generalized width
  97       // where each IO will have the same number of muxes.''')
  98
  99         for cell in p.muxed_cells:
 100             cnum = 'Bit#(' + str(int(math.log(len(cell) - 1, 2))) + ')'
 101             bsv_file.write(mux_interface.ifacefmt(cell[0], cnum))
 102
 103         bsv_file.write('''
 104       endinterface
 105
 106       interface PeripheralSide;
 107       // declare the interface to the IO cells.
 108       // Each IO cell will have 8 input field (output from pin mux
 109       // and on output field (input to pinmux)''')
 110         # ==============================================================
 111
 112         # == create method definitions for all peripheral interfaces ==#
 113         ifaces.ifacefmt(bsv_file)
 114
 115         # ==============================================================
 116
 117         # ===== finish interface definition and start module definition=======
 118         bsv_file.write('''
 119    endinterface
 120
 121    interface Ifc_pinmux;
 122       interface MuxSelectionLines mux_lines;
 123       interface PeripheralSide peripheral_side;
 124    endinterface
 125    (*synthesize*)
 126    module mkpinmux(Ifc_pinmux);
 127 ''')
 128         # ====================================================================
 129
 130         # ======================= create wire and registers =================#
 131         bsv_file.write('''
 132       // the followins wires capture the pin-mux selection
 133       // values for each mux assigned to a CELL
 134 ''')
 135         for cell in p.muxed_cells:
 136             bsv_file.write(mux_interface.wirefmt(
 137                 cell[0], 'Bit#(' + str(int(math.log(len(cell) - 1, 2))) + ')'))
 138
 139         ifaces.wirefmt(bsv_file)
 140
 141         bsv_file.write("\n")
 142         # ====================================================================
 143         # ========================= Actual pinmuxing ========================#
 144         bsv_file.write('''
 145       /*====== This where the muxing starts for each io-cell======*/
 146 ''')
 147         bsv_file.write(p.pinmux)
 148         bsv_file.write('''
 149       /*============================================================*/
 150 ''')
 151         # ====================================================================
 152         # ================= interface definitions for each method =============#
 153         bsv_file.write('''
 154     interface mux_lines = interface MuxSelectionLines
 155 ''')
 156         for cell in p.muxed_cells:
 157             bsv_file.write(
 158                 mux_interface.ifacedef(
 159                     cell[0], 'Bit#(' + str(int(
 160                         math.log(
 161                             len(cell) - 1, 2))) + ')'))
 162         bsv_file.write('''
 163     endinterface;
 164     interface peripheral_side = interface PeripheralSide
 165 ''')
 166         ifaces.ifacedef(bsv_file)
 167         bsv_file.write(footer)
 168         print("BSV file successfully generated: bsv_src/pinmux.bsv")
 169         # ======================================================================
 170
 171
 172 def write_ptp(ptp, p, ifaces):
 173     with open(ptp, 'w') as bsv_file:
 174         bsv_file.write(copyright + '''
 175 package PinTop;
 176     import pinmux::*;
 177     interface Ifc_PintTop;
 178         method ActionValue#(Bool) write(Bit#({0}) addr, Bit#({1}) data);
 179         method Tuple2#(Bool,Bit#({1})) read(Bit#({0}) addr);
 180         interface PeripheralSide peripheral_side;
 181     endinterface
 182
 183     module mkPinTop(Ifc_PintTop);
 184         // instantiate the pin-mux module here
 185         Ifc_pinmux pinmux <-mkpinmux;
 186
 187         // declare the registers which will be used to mux the IOs
 188 '''.format(p.ADDR_WIDTH, p.DATA_WIDTH))
 189
 190         for cell in p.muxed_cells:
 191             bsv_file.write('''
 192                 Reg#(Bit#({0})) rg_muxio_{1} <-mkReg(0);'''.format(
 193                 int(math.log(len(cell) - 1, 2)), cell[0]))
 194
 195         bsv_file.write('''
 196         // rule to connect the registers to the selection lines of the
 197         // pin-mux module
 198         rule connect_selection_registers;''')
 199
 200         for cell in p.muxed_cells:
 201             bsv_file.write('''
 202           pinmux.mux_lines.cell{0}_mux(rg_muxio_{0});'''.format(cell[0]))
 203
 204         bsv_file.write('''
 205         endrule
 206         // method definitions for the write user interface
 207         method ActionValue#(Bool) write(Bit#({2}) addr, Bit#({3}) data);
 208           Bool err=False;
 209           case (addr[{0}:{1}])'''.format(p.upper_offset, p.lower_offset,
 210                                          p.ADDR_WIDTH, p.DATA_WIDTH))
 211         index = 0
 212         for cell in p.muxed_cells:
 213             bsv_file.write('''
 214             {0}: rg_muxio_{1}<=truncate(data);'''.format(index, cell[0]))
 215             index = index + 1
 216
 217         bsv_file.write('''
 218             default: err=True;
 219           endcase
 220           return err;
 221         endmethod''')
 222
 223         bsv_file.write('''
 224         // method definitions for the read user interface
 225         method Tuple2#(Bool,Bit#({3})) read(Bit#({2}) addr);
 226           Bool err=False;
 227           Bit#(32) data=0;
 228           case (addr[{0}:{1}])'''.format(p.upper_offset, p.lower_offset,
 229                                          p.ADDR_WIDTH, p.DATA_WIDTH))
 230         index = 0
 231         for cell in p.muxed_cells:
 232             bsv_file.write('''
 233                 {0}: data=zeroExtend(rg_muxio_{1});'''.format(index, cell[0]))
 234             index = index + 1
 235
 236         bsv_file.write('''
 237             default:err=True;
 238           endcase
 239           return tuple2(err,data);
 240         endmethod
 241         interface peripheral_side=pinmux.peripheral_side;
 242     endmodule
 243 endpackage
 244 ''')
 245
 246
 247 def write_bvp(bvp, p, ifaces):
 248     # ######## Generate bus transactors ################
 249     with open(bvp, 'w') as bsv_file:
 250         bsv_file.write(axi4_lite.format(p.ADDR_WIDTH, p.DATA_WIDTH))
 251     # ##################################################