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 interface_decl import Interfaces, mux_interface, io_interface
  26 from parse import Parse
  27 from actual_pinmux import init
  28 from 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     init(p)
  67     ifaces = Interfaces(pth)
  68     ifaces.ifaceadd('io', p.N_IO, io_interface, 0)
  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     # package and interface declaration followed by
  81     # the generic io_cell definition
  82     with open(pmp, "w") as bsv_file:
  83         bsv_file.write(header)
  84
  85         bsv_file.write('''\
  86    interface MuxSelectionLines;
  87
  88       // declare the method which will capture the user pin-mux
  89       // selection values.The width of the input is dependent on the number
  90       // of muxes happening per IO. For now we have a generalized width
  91       // where each IO will have the same number of muxes.''')
  92
  93         for cell in p.muxed_cells:
  94             cnum = int(math.log(len(cell) - 1, 2))
  95             bsv_file.write(mux_interface.ifacefmt(cell[0], cnum))
  96
  97         bsv_file.write('''
  98       endinterface
  99
 100       interface PeripheralSide;
 101       // declare the interface to the IO cells.
 102       // Each IO cell will have 8 input field (output from pin mux
 103       // and on output field (input to pinmux)''')
 104         # ==============================================================
 105
 106         # == create method definitions for all peripheral interfaces ==#
 107         ifaces.ifacefmt(bsv_file)
 108
 109         # ==============================================================
 110
 111         # ===== finish interface definition and start module definition=======
 112         bsv_file.write('''
 113    endinterface
 114
 115    interface Ifc_pinmux;
 116       interface MuxSelectionLines mux_lines;
 117       interface PeripheralSide peripheral_side;
 118    endinterface
 119    (*synthesize*)
 120    module mkpinmux(Ifc_pinmux);
 121 ''')
 122         # ====================================================================
 123
 124         # ======================= create wire and registers =================#
 125         bsv_file.write('''
 126       // the followins wires capture the pin-mux selection
 127       // values for each mux assigned to a CELL
 128 ''')
 129         for cell in p.muxed_cells:
 130             bsv_file.write(mux_interface.wirefmt(
 131                 cell[0], int(math.log(len(cell) - 1, 2))))
 132
 133         ifaces.wirefmt(bsv_file)
 134
 135         bsv_file.write("\n")
 136         # ====================================================================
 137         # ========================= Actual pinmuxing ========================#
 138         bsv_file.write('''
 139       /*====== This where the muxing starts for each io-cell======*/
 140 ''')
 141         bsv_file.write(p.pinmux)
 142         bsv_file.write('''
 143       /*============================================================*/
 144 ''')
 145         # ====================================================================
 146         # ================= interface definitions for each method =============#
 147         bsv_file.write('''
 148     interface mux_lines = interface MuxSelectionLines
 149 ''')
 150         for cell in p.muxed_cells:
 151             bsv_file.write(mux_interface.ifacedef(cell[0],
 152                                                   int(math.log(len(cell) - 1, 2))))
 153         bsv_file.write('''
 154     endinterface;
 155     interface peripheral_side = interface PeripheralSide
 156 ''')
 157         ifaces.ifacedef(bsv_file)
 158         bsv_file.write(footer)
 159         print("BSV file successfully generated: bsv_src/pinmux.bsv")
 160         # ======================================================================
 161
 162     with open(ptp, 'w') as bsv_file:
 163         bsv_file.write(copyright + '''
 164 package PinTop;
 165     import pinmux::*;
 166     interface Ifc_PintTop;
 167         method ActionValue#(Bool) write(Bit#({0}) addr, Bit#({1}) data);
 168         method Tuple2#(Bool,Bit#({1})) read(Bit#({0}) addr);
 169         interface PeripheralSide peripheral_side;
 170     endinterface
 171
 172     module mkPinTop(Ifc_PintTop);
 173         // instantiate the pin-mux module here
 174         Ifc_pinmux pinmux <-mkpinmux;
 175
 176         // declare the registers which will be used to mux the IOs
 177 '''.format(p.ADDR_WIDTH, p.DATA_WIDTH))
 178
 179         for cell in p.muxed_cells:
 180             bsv_file.write('''
 181                 Reg#(Bit#({0})) rg_muxio_{1} <-mkReg(0);'''.format(
 182                 int(math.log(len(cell) - 1, 2)), cell[0]))
 183
 184         bsv_file.write('''
 185         // rule to connect the registers to the selection lines of the
 186         // pin-mux module
 187         rule connect_selection_registers;''')
 188
 189         for cell in p.muxed_cells:
 190             bsv_file.write('''
 191           pinmux.mux_lines.cell{0}_mux(rg_muxio_{0});'''.format(cell[0]))
 192
 193         bsv_file.write('''
 194         endrule
 195         // method definitions for the write user interface
 196         method ActionValue#(Bool) write(Bit#({2}) addr, Bit#({3}) data);
 197           Bool err=False;
 198           case (addr[{0}:{1}])'''.format(p.upper_offset, p.lower_offset,
 199                                          p.ADDR_WIDTH, p.DATA_WIDTH))
 200         index = 0
 201         for cell in p.muxed_cells:
 202             bsv_file.write('''
 203             {0}: rg_muxio_{1}<=truncate(data);'''.format(index, cell[0]))
 204             index = index + 1
 205
 206         bsv_file.write('''
 207             default: err=True;
 208           endcase
 209           return err;
 210         endmethod''')
 211
 212         bsv_file.write('''
 213         // method definitions for the read user interface
 214         method Tuple2#(Bool,Bit#({3})) read(Bit#({2}) addr);
 215           Bool err=False;
 216           Bit#(32) data=0;
 217           case (addr[{0}:{1}])'''.format(p.upper_offset, p.lower_offset,
 218                                          p.ADDR_WIDTH, p.DATA_WIDTH))
 219         index = 0
 220         for cell in p.muxed_cells:
 221             bsv_file.write('''
 222                 {0}: data=zeroExtend(rg_muxio_{1});'''.format(index, cell[0]))
 223             index = index + 1
 224
 225         bsv_file.write('''
 226             default:err=True;
 227           endcase
 228           return tuple2(err,data);
 229         endmethod
 230         interface peripheral_side=pinmux.peripheral_side;
 231     endmodule
 232 endpackage
 233 ''')
 234
 235     # ######## Generate bus transactors ################
 236     with open(bvp, 'w') as bsv_file:
 237         bsv_file.write(axi4_lite.format(p.ADDR_WIDTH, p.DATA_WIDTH))
 238     # ##################################################