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         print max_num_cells, cell, int(math.ceil(math.log(max_num_cells, 2)))
 117     return int(math.log(max_num_cells+1, 2))
 118
 119
 120 def write_pmp(pmp, p, ifaces):
 121     # package and interface declaration followed by
 122     # the generic io_cell definition
 123     with open(pmp, "w") as bsv_file:
 124         bsv_file.write(header)
 125
 126         cell_bit_width = 'Bit#(%d)' % get_cell_bit_width(p)
 127         bsv_file.write('''\
 128    interface MuxSelectionLines;
 129
 130       // declare the method which will capture the user pin-mux
 131       // selection values.The width of the input is dependent on the number
 132       // of muxes happening per IO. For now we have a generalized width
 133       // where each IO will have the same number of muxes.''')
 134
 135         for cell in p.muxed_cells:
 136             bsv_file.write(mux_interface.ifacefmt(cell[0], cell_bit_width))
 137
 138         bsv_file.write('''
 139       endinterface
 140
 141       interface PeripheralSide;
 142       // declare the interface to the IO cells.
 143       // Each IO cell will have 8 input field (output from pin mux
 144       // and on output field (input to pinmux)''')
 145         # ==============================================================
 146
 147         # == create method definitions for all peripheral interfaces ==#
 148         ifaces.ifacefmt(bsv_file)
 149
 150         # ==============================================================
 151
 152         # ===== finish interface definition and start module definition=======
 153         bsv_file.write('''
 154    endinterface
 155
 156    interface Ifc_pinmux;
 157       interface MuxSelectionLines mux_lines;
 158       interface PeripheralSide peripheral_side;
 159    endinterface
 160    (*synthesize*)
 161    module mkpinmux(Ifc_pinmux);
 162 ''')
 163         # ====================================================================
 164
 165         # ======================= create wire and registers =================#
 166         bsv_file.write('''
 167       // the followins wires capture the pin-mux selection
 168       // values for each mux assigned to a CELL
 169 ''')
 170         for cell in p.muxed_cells:
 171             bsv_file.write(mux_interface.wirefmt(
 172                 cell[0], cell_bit_width))
 173
 174         ifaces.wirefmt(bsv_file)
 175
 176         bsv_file.write("\n")
 177         # ====================================================================
 178         # ========================= Actual pinmuxing ========================#
 179         bsv_file.write('''
 180       /*====== This where the muxing starts for each io-cell======*/
 181 ''')
 182         bsv_file.write(p.pinmux)
 183         bsv_file.write('''
 184       /*============================================================*/
 185 ''')
 186         # ====================================================================
 187         # ================= interface definitions for each method =============#
 188         bsv_file.write('''
 189     interface mux_lines = interface MuxSelectionLines
 190 ''')
 191         for cell in p.muxed_cells:
 192             bsv_file.write(
 193                 mux_interface.ifacedef(
 194                     cell[0], cell_bit_width))
 195         bsv_file.write('''
 196     endinterface;
 197     interface peripheral_side = interface PeripheralSide
 198 ''')
 199         ifaces.ifacedef(bsv_file)
 200         bsv_file.write(footer)
 201         print("BSV file successfully generated: bsv_src/pinmux.bsv")
 202         # ======================================================================
 203
 204
 205 def write_ptp(ptp, p, ifaces):
 206     with open(ptp, 'w') as bsv_file:
 207         bsv_file.write(copyright + '''
 208 package PinTop;
 209     import pinmux::*;
 210     interface Ifc_PintTop;
 211         method ActionValue#(Bool) write(Bit#({0}) addr, Bit#({1}) data);
 212         method Tuple2#(Bool,Bit#({1})) read(Bit#({0}) addr);
 213         interface PeripheralSide peripheral_side;
 214     endinterface
 215
 216     module mkPinTop(Ifc_PintTop);
 217         // instantiate the pin-mux module here
 218         Ifc_pinmux pinmux <-mkpinmux;
 219
 220         // declare the registers which will be used to mux the IOs
 221 '''.format(p.ADDR_WIDTH, p.DATA_WIDTH))
 222
 223         cell_bit_width = str(get_cell_bit_width(p))
 224         for cell in p.muxed_cells:
 225             bsv_file.write('''
 226                 Reg#(Bit#({0})) rg_muxio_{1} <-mkReg(0);'''.format(
 227                 cell_bit_width, cell[0]))
 228
 229         bsv_file.write('''
 230         // rule to connect the registers to the selection lines of the
 231         // pin-mux module
 232         rule connect_selection_registers;''')
 233
 234         for cell in p.muxed_cells:
 235             bsv_file.write('''
 236           pinmux.mux_lines.cell{0}_mux(rg_muxio_{0});'''.format(cell[0]))
 237
 238         bsv_file.write('''
 239         endrule
 240         // method definitions for the write user interface
 241         method ActionValue#(Bool) write(Bit#({2}) addr, Bit#({3}) data);
 242           Bool err=False;
 243           case (addr[{0}:{1}])'''.format(p.upper_offset, p.lower_offset,
 244                                          p.ADDR_WIDTH, p.DATA_WIDTH))
 245         index = 0
 246         for cell in p.muxed_cells:
 247             bsv_file.write('''
 248             {0}: rg_muxio_{1}<=truncate(data);'''.format(index, cell[0]))
 249             index = index + 1
 250
 251         bsv_file.write('''
 252             default: err=True;
 253           endcase
 254           return err;
 255         endmethod''')
 256
 257         bsv_file.write('''
 258         // method definitions for the read user interface
 259         method Tuple2#(Bool,Bit#({3})) read(Bit#({2}) addr);
 260           Bool err=False;
 261           Bit#(32) data=0;
 262           case (addr[{0}:{1}])'''.format(p.upper_offset, p.lower_offset,
 263                                          p.ADDR_WIDTH, p.DATA_WIDTH))
 264         index = 0
 265         for cell in p.muxed_cells:
 266             bsv_file.write('''
 267                 {0}: data=zeroExtend(rg_muxio_{1});'''.format(index, cell[0]))
 268             index = index + 1
 269
 270         bsv_file.write('''
 271             default:err=True;
 272           endcase
 273           return tuple2(err,data);
 274         endmethod
 275         interface peripheral_side=pinmux.peripheral_side;
 276     endmodule
 277 endpackage
 278 ''')
 279
 280
 281 def write_bvp(bvp, p, ifaces):
 282     # ######## Generate bus transactors ################
 283     with open(bvp, 'w') as bsv_file:
 284         bsv_file.write(axi4_lite.format(p.ADDR_WIDTH, p.DATA_WIDTH))
 285     # ##################################################