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 shutil
  20 import os
  21 import os.path
  22 import time
  23 import math
  24
  25 # project module imports
  26 from bsv.interface_decl import Interfaces, mux_interface, io_interface
  27 from parse import Parse
  28 from bsv.actual_pinmux import init
  29 from bsv.bus_transactors import axi4_lite
  30
  31 copyright = '''
  32 /*
  33    This BSV file has been generated by the PinMux tool available at:
  34    https://bitbucket.org/casl/pinmux.
  35
  36    Authors: Neel Gala, Luke
  37    Date of generation: ''' + time.strftime("%c") + '''
  38 */
  39 '''
  40 header = copyright + '''
  41 package pinmux;
  42
  43    // FunctionType: contains the active wires of a function.  That INCLUDES
  44    // GPIO (as GPIO is also a "Function").  These are what get muxed.
  45    // However, only GPIO "Functions" will end up with Register SRAMs.
  46    typedef struct{
  47       Bit#(1) outputval;      // output from function to pad            bit2
  48       Bit#(1) inputval;       // input  from pad to function            bit1
  49       Bit#(1) output_en;      // output enable from core to pad         bit0
  50    } FunctionType deriving(Eq,Bits,FShow);
  51
  52    typedef struct{
  53       Bit#(1) outputval;      // output from core to pad                bit7
  54       Bit#(1) output_en;      // output enable from core to pad         bit6
  55       Bit#(1) input_en;       // input enable from core to io_cell      bit5
  56    } GenericIOType deriving(Eq,Bits,FShow);
  57
  58 '''
  59 footer = '''
  60      endinterface;
  61    endmodule
  62 endpackage
  63 '''
  64
  65
  66 def pinmuxgen(pth=None, verify=True):
  67     """ populating the file with the code
  68     """
  69
  70     p = Parse(pth, verify)
  71     ifaces = Interfaces(pth)
  72     ifaces.ifaceadd('io', p.N_IO, io_interface, 0)
  73     init(p, ifaces)
  74
  75     bp = 'bsv_src'
  76     if pth:
  77         bp = os.path.join(pth, bp)
  78     if not os.path.exists(bp):
  79         os.makedirs(bp)
  80     bl = os.path.join(bp, 'bsv_lib')
  81     if not os.path.exists(bl):
  82         os.makedirs(bl)
  83
  84     cwd = os.path.split(__file__)[0]
  85
  86     # copy over template and library files
  87     shutil.copyfile(os.path.join(cwd, 'Makefile.template'),
  88                     os.path.join(bp, 'Makefile'))
  89     cwd = os.path.join(cwd, 'bsv_lib')
  90     for fname in ['AXI4_Lite_Types.bsv', 'Semi_FIFOF.bsv']:
  91         shutil.copyfile(os.path.join(cwd, fname),
  92                         os.path.join(bl, fname))
  93
  94     bus = os.path.join(bp, 'busenable.bsv')
  95     pmp = os.path.join(bp, 'pinmux.bsv')
  96     ptp = os.path.join(bp, 'PinTop.bsv')
  97     bvp = os.path.join(bp, 'bus.bsv')
  98
  99     write_pmp(pmp, p, ifaces)
 100     write_ptp(ptp, p, ifaces)
 101     write_bvp(bvp, p, ifaces)
 102     write_bus(bus, p, ifaces)
 103
 104
 105 def write_bus(bus, p, ifaces):
 106     # package and interface declaration followed by
 107     # the generic io_cell definition
 108     with open(bus, "w") as bsv_file:
 109         ifaces.busfmt(bsv_file)
 110
 111
 112 def get_cell_bit_width(p):
 113     max_num_cells = 0
 114     for cell in p.muxed_cells:
 115         max_num_cells = max(len(cell) - 1, max_num_cells)
 116     return int(math.log(max_num_cells+1, 2))
 117
 118
 119 def write_pmp(pmp, p, ifaces):
 120     # package and interface declaration followed by
 121     # the generic io_cell definition
 122     with open(pmp, "w") as bsv_file:
 123         bsv_file.write(header)
 124
 125         cell_bit_width = 'Bit#(%d)' % get_cell_bit_width(p)
 126         bsv_file.write('''\
 127    interface MuxSelectionLines;
 128
 129       // declare the method which will capture the user pin-mux
 130       // selection values.The width of the input is dependent on the number
 131       // of muxes happening per IO. For now we have a generalized width
 132       // where each IO will have the same number of muxes.''')
 133
 134         for cell in p.muxed_cells:
 135             bsv_file.write(mux_interface.ifacefmt(cell[0], cell_bit_width))
 136
 137         bsv_file.write('''
 138       endinterface
 139
 140       interface PeripheralSide;
 141       // declare the interface to the IO cells.
 142       // Each IO cell will have 8 input field (output from pin mux
 143       // and on output field (input to pinmux)''')
 144         # ==============================================================
 145
 146         # == create method definitions for all peripheral interfaces ==#
 147         ifaces.ifacefmt(bsv_file)
 148
 149         # ==============================================================
 150
 151         # ===== finish interface definition and start module definition=======
 152         bsv_file.write('''
 153    endinterface
 154
 155    interface Ifc_pinmux;
 156       interface MuxSelectionLines mux_lines;
 157       interface PeripheralSide peripheral_side;
 158    endinterface
 159    (*synthesize*)
 160    module mkpinmux(Ifc_pinmux);
 161 ''')
 162         # ====================================================================
 163
 164         # ======================= create wire and registers =================#
 165         bsv_file.write('''
 166       // the followins wires capture the pin-mux selection
 167       // values for each mux assigned to a CELL
 168 ''')
 169         for cell in p.muxed_cells:
 170             bsv_file.write(mux_interface.wirefmt(
 171                 cell[0], cell_bit_width))
 172
 173         ifaces.wirefmt(bsv_file)
 174
 175         bsv_file.write("\n")
 176         # ====================================================================
 177         # ========================= Actual pinmuxing ========================#
 178         bsv_file.write('''
 179       /*====== This where the muxing starts for each io-cell======*/
 180 ''')
 181         bsv_file.write(p.pinmux)
 182         bsv_file.write('''
 183       /*============================================================*/
 184 ''')
 185         # ====================================================================
 186         # ================= interface definitions for each method =============#
 187         bsv_file.write('''
 188     interface mux_lines = interface MuxSelectionLines
 189 ''')
 190         for cell in p.muxed_cells:
 191             bsv_file.write(
 192                 mux_interface.ifacedef(
 193                     cell[0], cell_bit_width))
 194         bsv_file.write('''
 195     endinterface;
 196     interface peripheral_side = interface PeripheralSide
 197 ''')
 198         ifaces.ifacedef(bsv_file)
 199         bsv_file.write(footer)
 200         print("BSV file successfully generated: bsv_src/pinmux.bsv")
 201         # ======================================================================
 202
 203
 204 def write_ptp(ptp, p, ifaces):
 205     with open(ptp, 'w') as bsv_file:
 206         bsv_file.write(copyright + '''
 207 package PinTop;
 208     import pinmux::*;
 209     interface Ifc_PintTop;
 210         method ActionValue#(Bool) write(Bit#({0}) addr, Bit#({1}) data);
 211         method Tuple2#(Bool,Bit#({1})) read(Bit#({0}) addr);
 212         interface PeripheralSide peripheral_side;
 213     endinterface
 214
 215     module mkPinTop(Ifc_PintTop);
 216         // instantiate the pin-mux module here
 217         Ifc_pinmux pinmux <-mkpinmux;
 218
 219         // declare the registers which will be used to mux the IOs
 220 '''.format(p.ADDR_WIDTH, p.DATA_WIDTH))
 221
 222         cell_bit_width = str(get_cell_bit_width(p))
 223         for cell in p.muxed_cells:
 224             bsv_file.write('''
 225                 Reg#(Bit#({0})) rg_muxio_{1} <-mkReg(0);'''.format(
 226                 cell_bit_width, cell[0]))
 227
 228         bsv_file.write('''
 229         // rule to connect the registers to the selection lines of the
 230         // pin-mux module
 231         rule connect_selection_registers;''')
 232
 233         for cell in p.muxed_cells:
 234             bsv_file.write('''
 235           pinmux.mux_lines.cell{0}_mux(rg_muxio_{0});'''.format(cell[0]))
 236
 237         bsv_file.write('''
 238         endrule
 239         // method definitions for the write user interface
 240         method ActionValue#(Bool) write(Bit#({2}) addr, Bit#({3}) data);
 241           Bool err=False;
 242           case (addr[{0}:{1}])'''.format(p.upper_offset, p.lower_offset,
 243                                          p.ADDR_WIDTH, p.DATA_WIDTH))
 244         index = 0
 245         for cell in p.muxed_cells:
 246             bsv_file.write('''
 247             {0}: rg_muxio_{1}<=truncate(data);'''.format(index, cell[0]))
 248             index = index + 1
 249
 250         bsv_file.write('''
 251             default: err=True;
 252           endcase
 253           return err;
 254         endmethod''')
 255
 256         bsv_file.write('''
 257         // method definitions for the read user interface
 258         method Tuple2#(Bool,Bit#({3})) read(Bit#({2}) addr);
 259           Bool err=False;
 260           Bit#(32) data=0;
 261           case (addr[{0}:{1}])'''.format(p.upper_offset, p.lower_offset,
 262                                          p.ADDR_WIDTH, p.DATA_WIDTH))
 263         index = 0
 264         for cell in p.muxed_cells:
 265             bsv_file.write('''
 266                 {0}: data=zeroExtend(rg_muxio_{1});'''.format(index, cell[0]))
 267             index = index + 1
 268
 269         bsv_file.write('''
 270             default:err=True;
 271           endcase
 272           return tuple2(err,data);
 273         endmethod
 274         interface peripheral_side=pinmux.peripheral_side;
 275     endmodule
 276 endpackage
 277 ''')
 278
 279
 280 def write_bvp(bvp, p, ifaces):
 281     # ######## Generate bus transactors ################
 282     with open(bvp, 'w') as bsv_file:
 283         bsv_file.write(axi4_lite.format(p.ADDR_WIDTH, p.DATA_WIDTH))
 284     # ##################################################