| 1 |
3 |
robfinch |
// ============================================================================
|
| 2 |
|
|
// __
|
| 3 |
|
|
// \\__/ o\ (C) 2013,2015 Robert Finch, Stratford
|
| 4 |
|
|
// \ __ / All rights reserved.
|
| 5 |
|
|
// \/_// robfinch<remove>@finitron.ca
|
| 6 |
|
|
// ||
|
| 7 |
|
|
//
|
| 8 |
|
|
// This source file is free software: you can redistribute it and/or modify
|
| 9 |
|
|
// it under the terms of the GNU Lesser General Public License as published
|
| 10 |
|
|
// by the Free Software Foundation, either version 3 of the License, or
|
| 11 |
|
|
// (at your option) any later version.
|
| 12 |
|
|
//
|
| 13 |
|
|
// This source file is distributed in the hope that it will be useful,
|
| 14 |
|
|
// but WITHOUT ANY WARRANTY; without even the implied warranty of
|
| 15 |
|
|
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
| 16 |
|
|
// GNU General Public License for more details.
|
| 17 |
|
|
//
|
| 18 |
|
|
// You should have received a copy of the GNU General Public License
|
| 19 |
|
|
// along with this program. If not, see <http://www.gnu.org/licenses/>.
|
| 20 |
|
|
//
|
| 21 |
|
|
//
|
| 22 |
|
|
// Thor SuperScalar
|
| 23 |
|
|
// Execute combinational logic
|
| 24 |
|
|
//
|
| 25 |
|
|
// ============================================================================
|
| 26 |
|
|
//
|
| 27 |
|
|
wire [DBW-1:0] alu0_out, alu1_out;
|
| 28 |
|
|
wire alu0_done,alu1_done;
|
| 29 |
13 |
robfinch |
wire alu0_idle,alu1_idle;
|
| 30 |
3 |
robfinch |
wire alu0_divByZero, alu1_divByZero;
|
| 31 |
13 |
robfinch |
wire alu0_abort,alu1_abort;
|
| 32 |
3 |
robfinch |
|
| 33 |
|
|
Thor_alu #(.DBW(DBW),.BIG(1)) ualu0
|
| 34 |
|
|
(
|
| 35 |
|
|
.corenum(corenum),
|
| 36 |
13 |
robfinch |
.rst(rst_i),
|
| 37 |
3 |
robfinch |
.clk(clk),
|
| 38 |
|
|
.alu_ld(alu0_ld),
|
| 39 |
13 |
robfinch |
.alu_abort(alu0_abort),
|
| 40 |
3 |
robfinch |
.alu_op(alu0_op),
|
| 41 |
|
|
.alu_fn(alu0_fn),
|
| 42 |
|
|
.alu_argA(alu0_argA),
|
| 43 |
|
|
.alu_argB(alu0_argB),
|
| 44 |
|
|
.alu_argC(alu0_argC),
|
| 45 |
|
|
.alu_argI(alu0_argI),
|
| 46 |
|
|
.alu_pc(alu0_pc),
|
| 47 |
|
|
.insnsz(alu0_insnsz),
|
| 48 |
|
|
.o(alu0_out),
|
| 49 |
|
|
.alu_done(alu0_done),
|
| 50 |
13 |
robfinch |
.alu_idle(alu0_idle),
|
| 51 |
3 |
robfinch |
.alu_divByZero(alu0_divByZero)
|
| 52 |
|
|
);
|
| 53 |
|
|
|
| 54 |
|
|
Thor_alu #(.DBW(DBW),.BIG(ALU1BIG)) ualu1
|
| 55 |
|
|
(
|
| 56 |
|
|
.corenum(corenum),
|
| 57 |
13 |
robfinch |
.rst(rst_i),
|
| 58 |
3 |
robfinch |
.clk(clk),
|
| 59 |
|
|
.alu_ld(alu1_ld),
|
| 60 |
13 |
robfinch |
.alu_abort(alu1_abort),
|
| 61 |
3 |
robfinch |
.alu_op(alu1_op),
|
| 62 |
|
|
.alu_fn(alu1_fn),
|
| 63 |
|
|
.alu_argA(alu1_argA),
|
| 64 |
|
|
.alu_argB(alu1_argB),
|
| 65 |
|
|
.alu_argC(alu1_argC),
|
| 66 |
|
|
.alu_argI(alu1_argI),
|
| 67 |
|
|
.alu_pc(alu1_pc),
|
| 68 |
|
|
.insnsz(alu1_insnsz),
|
| 69 |
|
|
.o(alu1_out),
|
| 70 |
|
|
.alu_done(alu1_done),
|
| 71 |
13 |
robfinch |
.alu_idle(alu1_idle),
|
| 72 |
3 |
robfinch |
.alu_divByZero(alu1_divByZero)
|
| 73 |
|
|
);
|
| 74 |
|
|
|
| 75 |
|
|
function fnPredicate;
|
| 76 |
|
|
input [3:0] pr;
|
| 77 |
|
|
input [3:0] cond;
|
| 78 |
|
|
|
| 79 |
|
|
case(cond)
|
| 80 |
|
|
PF: fnPredicate = 1'b0;
|
| 81 |
|
|
PT: fnPredicate = 1'b1;
|
| 82 |
|
|
PEQ: fnPredicate = pr[0];
|
| 83 |
|
|
PNE: fnPredicate = !pr[0];
|
| 84 |
|
|
PLE: fnPredicate = pr[0]|pr[1];
|
| 85 |
|
|
PGT: fnPredicate = !(pr[0]|pr[1]);
|
| 86 |
|
|
PLT: fnPredicate = pr[1];
|
| 87 |
|
|
PGE: fnPredicate = !pr[1];
|
| 88 |
|
|
PLEU: fnPredicate = pr[0]|pr[2];
|
| 89 |
|
|
PGTU: fnPredicate = !(pr[0]|pr[2]);
|
| 90 |
|
|
PLTU: fnPredicate = pr[2];
|
| 91 |
|
|
PGEU: fnPredicate = !pr[2];
|
| 92 |
|
|
default: fnPredicate = 1'b1;
|
| 93 |
|
|
endcase
|
| 94 |
|
|
|
| 95 |
|
|
endfunction
|
| 96 |
|
|
|
| 97 |
|
|
wire alu0_cmtw = fnPredicate(alu0_pred, alu0_cond);
|
| 98 |
|
|
wire alu1_cmtw = fnPredicate(alu1_pred, alu1_cond);
|
| 99 |
|
|
|
| 100 |
|
|
always @*
|
| 101 |
|
|
begin
|
| 102 |
|
|
alu0_cmt <= alu0_cmtw;
|
| 103 |
|
|
alu1_cmt <= alu1_cmtw;
|
| 104 |
|
|
|
| 105 |
|
|
alu0_bus <= alu0_cmtw ? alu0_out : alu0_argT;
|
| 106 |
|
|
alu1_bus <= alu1_cmtw ? alu1_out : alu1_argT;
|
| 107 |
|
|
|
| 108 |
|
|
alu0_v <= alu0_dataready;
|
| 109 |
|
|
alu1_v <= alu1_dataready;
|
| 110 |
|
|
|
| 111 |
|
|
alu0_id <= alu0_sourceid;
|
| 112 |
|
|
alu1_id <= alu1_sourceid;
|
| 113 |
|
|
end
|
| 114 |
13 |
robfinch |
assign alu0_abort = !alu0_cmt;
|
| 115 |
|
|
assign alu1_abort = !alu1_cmt;
|
| 116 |
3 |
robfinch |
|
| 117 |
|
|
// Special flag nybble is used for INT and SYS instructions in order to turn off
|
| 118 |
|
|
// segmentation while the vector jump is taking place.
|
| 119 |
|
|
|
| 120 |
|
|
always @(alu0_op or alu0_fn or alu0_argA or alu0_argI or alu0_insnsz or alu0_pc or alu0_bt)
|
| 121 |
|
|
case(alu0_op)
|
| 122 |
13 |
robfinch |
`JSR,`JSRS,`JSRZ,`RTD,`RTE,`RTI,`RTS2:
|
| 123 |
3 |
robfinch |
alu0_misspc <= alu0_argA + alu0_argI;
|
| 124 |
|
|
`LOOP,`SYNC:
|
| 125 |
|
|
alu0_misspc <= alu0_pc + alu0_insnsz;
|
| 126 |
13 |
robfinch |
`RTS:
|
| 127 |
3 |
robfinch |
alu0_misspc <= alu0_argA + alu0_fn[3:0];
|
| 128 |
|
|
`SYS,`INT:
|
| 129 |
13 |
robfinch |
alu0_misspc <= {1'b1,alu0_argA + alu0_argI};
|
| 130 |
3 |
robfinch |
default:
|
| 131 |
|
|
alu0_misspc <= (alu0_bt ? alu0_pc + alu0_insnsz : alu0_pc + alu0_insnsz + alu0_argI);
|
| 132 |
|
|
endcase
|
| 133 |
|
|
|
| 134 |
|
|
always @(alu1_op or alu1_fn or alu1_argA or alu1_argI or alu1_insnsz or alu1_pc or alu1_bt)
|
| 135 |
|
|
case(alu1_op)
|
| 136 |
13 |
robfinch |
`JSR,`JSRS,`JSRZ,`RTD,`RTE,`RTI,`RTS2:
|
| 137 |
3 |
robfinch |
alu1_misspc <= alu1_argA + alu1_argI;
|
| 138 |
|
|
`LOOP,`SYNC:
|
| 139 |
|
|
alu1_misspc <= alu1_pc + alu1_insnsz;
|
| 140 |
13 |
robfinch |
`RTS:
|
| 141 |
3 |
robfinch |
alu1_misspc <= alu1_argA + alu1_fn[3:0];
|
| 142 |
|
|
`SYS,`INT:
|
| 143 |
13 |
robfinch |
alu1_misspc <= {1'b1,alu1_argA + alu1_argI};
|
| 144 |
3 |
robfinch |
default:
|
| 145 |
|
|
alu1_misspc <= (alu1_bt ? alu1_pc + alu1_insnsz : alu1_pc + alu1_insnsz + alu1_argI);
|
| 146 |
|
|
endcase
|
| 147 |
10 |
robfinch |
|
| 148 |
|
|
always @(dram0_fn or dram0_misspc or dram_bus)
|
| 149 |
|
|
case (dram0_fn[1:0])
|
| 150 |
|
|
2'd1: jmpi_misspc <= {dram0_misspc[DBW-1:16],dram_bus[15:0]};
|
| 151 |
|
|
2'd2: jmpi_misspc <= (DBW==32) ? dram_bus[31:0] : {dram0_misspc[63:32],dram_bus[31:0]};
|
| 152 |
|
|
2'd3: jmpi_misspc <= dram_bus[DBW-1:0];
|
| 153 |
|
|
default: jmpi_misspc <= 32'h00000FA0; // unimplemented instruction vector
|
| 154 |
|
|
endcase
|
| 155 |
3 |
robfinch |
/*
|
| 156 |
|
|
assign alu0_misspc = (alu0_op == `JSR || alu0_op==`JSRS || alu0_op==`JSRZ ||
|
| 157 |
|
|
alu0_op==`RTS || alu0_op==`RTS2 || alu0_op == `RTE || alu0_op==`RTI || alu0_op==`LOOP) ? alu0_argA + alu0_argI :
|
| 158 |
|
|
(alu0_op == `SYS || alu0_op==`INT) ? alu0_argA + {alu0_argI[DBW-5:0],4'b0} :
|
| 159 |
|
|
(alu0_bt ? alu0_pc + alu0_insnsz : alu0_pc + alu0_insnsz + alu0_argI),
|
| 160 |
|
|
alu1_misspc = (alu1_op == `JSR || alu1_op==`JSRS || alu1_op==`JSRZ ||
|
| 161 |
|
|
alu1_op==`RTS || alu1_op == `RTE || alu1_op==`RTI || alu1_op==`LOOP) ? alu1_argA + alu1_argI :
|
| 162 |
|
|
(alu1_op == `SYS || alu1_op==`INT) ? alu1_argA + {alu1_argI[DBW-5:0],4'b0} :
|
| 163 |
|
|
(alu1_bt ? alu1_pc + alu1_insnsz : alu1_pc + alu1_insnsz + alu1_argI);
|
| 164 |
|
|
*/
|
| 165 |
|
|
assign alu0_exc = (fnIsKMOnly(alu0_op) && !km) ? `EXC_PRIV :
|
| 166 |
|
|
(alu0_done && alu0_divByZero) ? `EXC_DBZ : `EXC_NONE;
|
| 167 |
|
|
|
| 168 |
|
|
// ? `EXC_NONE
|
| 169 |
|
|
// : (alu0_argB[`INSTRUCTION_S1] == `SYS_NONE) ? `EXC_NONE
|
| 170 |
|
|
// : (alu0_argB[`INSTRUCTION_S1] == `SYS_CALL) ? alu0_argB[`INSTRUCTION_S2]
|
| 171 |
|
|
// : (alu0_argB[`INSTRUCTION_S1] == `SYS_MFSR) ? `EXC_NONE
|
| 172 |
|
|
// : (alu0_argB[`INSTRUCTION_S1] == `SYS_MTSR) ? `EXC_NONE
|
| 173 |
|
|
// : (alu0_argB[`INSTRUCTION_S1] == `SYS_RFU1) ? `EXC_INVALID
|
| 174 |
|
|
// : (alu0_argB[`INSTRUCTION_S1] == `SYS_RFU2) ? `EXC_INVALID
|
| 175 |
|
|
// : (alu0_argB[`INSTRUCTION_S1] == `SYS_RFU3) ? `EXC_INVALID
|
| 176 |
|
|
// : (alu0_argB[`INSTRUCTION_S1] == `SYS_EXC) ? alu0_argB[`INSTRUCTION_S2]
|
| 177 |
|
|
// : `EXC_INVALID;
|
| 178 |
|
|
|
| 179 |
|
|
assign alu1_exc = (fnIsKMOnly(alu1_op) && !km) ? `EXC_PRIV :
|
| 180 |
|
|
(alu1_done && alu1_divByZero) ? `EXC_DBZ : `EXC_NONE;
|
| 181 |
|
|
|
| 182 |
|
|
// ? `EXC_NONE
|
| 183 |
|
|
// : (alu1_argB[`INSTRUCTION_S1] == `SYS_NONE) ? `EXC_NONE
|
| 184 |
|
|
// : (alu1_argB[`INSTRUCTION_S1] == `SYS_CALL) ? alu1_argB[`INSTRUCTION_S2]
|
| 185 |
|
|
// : (alu1_argB[`INSTRUCTION_S1] == `SYS_MFSR) ? `EXC_NONE
|
| 186 |
|
|
// : (alu1_argB[`INSTRUCTION_S1] == `SYS_MTSR) ? `EXC_NONE
|
| 187 |
|
|
// : (alu1_argB[`INSTRUCTION_S1] == `SYS_RFU1) ? `EXC_INVALID
|
| 188 |
|
|
// : (alu1_argB[`INSTRUCTION_S1] == `SYS_RFU2) ? `EXC_INVALID
|
| 189 |
|
|
// : (alu1_argB[`INSTRUCTION_S1] == `SYS_RFU3) ? `EXC_INVALID
|
| 190 |
|
|
// : (alu1_argB[`INSTRUCTION_S1] == `SYS_EXC) ? alu1_argB[`INSTRUCTION_S2]
|
| 191 |
|
|
// : `EXC_INVALID;
|
| 192 |
|
|
|
| 193 |
|
|
assign alu0_branchmiss = alu0_dataready &&
|
| 194 |
|
|
((fnIsBranch(alu0_op)) ? ((alu0_cmt && !alu0_bt) || (!alu0_cmt && alu0_bt))
|
| 195 |
13 |
robfinch |
: !alu0_cmt ? (alu0_op==`LOOP)
|
| 196 |
|
|
: (alu0_cmt && (alu0_op==`SYNC || alu0_op == `JSR || alu0_op == `JSRS || alu0_op == `JSRZ ||
|
| 197 |
3 |
robfinch |
alu0_op==`SYS || alu0_op==`INT ||
|
| 198 |
10 |
robfinch |
alu0_op==`RTS || alu0_op==`RTS2 || alu0_op==`RTD || alu0_op == `RTE || alu0_op==`RTI || ((alu0_op==`LOOP) && (alu0_argA == 64'd0)))));
|
| 199 |
3 |
robfinch |
|
| 200 |
|
|
assign alu1_branchmiss = alu1_dataready &&
|
| 201 |
|
|
((fnIsBranch(alu1_op)) ? ((alu1_cmt && !alu1_bt) || (!alu1_cmt && alu1_bt))
|
| 202 |
13 |
robfinch |
: !alu1_cmt ? (alu1_op==`LOOP)
|
| 203 |
|
|
: (alu1_cmt && (alu1_op==`SYNC || alu1_op == `JSR || alu1_op == `JSRS || alu1_op == `JSRZ ||
|
| 204 |
3 |
robfinch |
alu1_op==`SYS || alu1_op==`INT ||
|
| 205 |
10 |
robfinch |
alu1_op==`RTS || alu1_op==`RTS2 || alu1_op==`RTD || alu1_op == `RTE || alu1_op==`RTI || ((alu1_op==`LOOP) && (alu1_argA == 64'd0)))));
|
| 206 |
3 |
robfinch |
|
| 207 |
10 |
robfinch |
assign branchmiss = (alu0_branchmiss | alu1_branchmiss | mem_stringmiss | jmpi_miss),
|
| 208 |
|
|
misspc = (jmpi_miss ? jmpi_misspc : mem_stringmiss ? dram0_misspc : alu0_branchmiss ? alu0_misspc : alu1_misspc),
|
| 209 |
|
|
missid = (jmpi_miss ? dram0_id : mem_stringmiss ? dram0_id : alu0_branchmiss ? alu0_sourceid : alu1_sourceid);
|
| 210 |
3 |
robfinch |
|
| 211 |
|
|
`ifdef FLOATING_POINT
|
| 212 |
|
|
wire fp0_exception;
|
| 213 |
|
|
|
| 214 |
|
|
fpUnit ufp0
|
| 215 |
|
|
(
|
| 216 |
|
|
.rst(rst_i),
|
| 217 |
|
|
.clk(clk),
|
| 218 |
|
|
.ce(1'b1),
|
| 219 |
|
|
.op(fp0_op),
|
| 220 |
|
|
.fn(fp0_fn),
|
| 221 |
|
|
.ld(fp0_ld),
|
| 222 |
|
|
.a(fp0_argA),
|
| 223 |
|
|
.b(fp0_argB),
|
| 224 |
|
|
.o(fp0_bus),
|
| 225 |
|
|
.exception(fp0_exception)
|
| 226 |
|
|
);
|
| 227 |
|
|
|
| 228 |
|
|
reg [7:0] cnt;
|
| 229 |
|
|
always @(posedge clk)
|
| 230 |
|
|
if (rst_i)
|
| 231 |
|
|
cnt <= 8'h00;
|
| 232 |
|
|
else begin
|
| 233 |
|
|
if (fp0_ld)
|
| 234 |
|
|
cnt <= 8'h00;
|
| 235 |
|
|
else begin
|
| 236 |
|
|
if (cnt < 8'hff)
|
| 237 |
|
|
cnt <= cnt + 8'd1;
|
| 238 |
|
|
end
|
| 239 |
|
|
end
|
| 240 |
|
|
|
| 241 |
|
|
always @*
|
| 242 |
|
|
begin
|
| 243 |
|
|
case(fp0_op)
|
| 244 |
|
|
`FLOAT:
|
| 245 |
|
|
case(fp0_fn)
|
| 246 |
|
|
`FCMP,`FCMPS: fp0_done = 1'b1; // These ops are done right away
|
| 247 |
|
|
`FADD,`FSUB,`FMUL,`FADDS,`FSUBS,`FMULS:
|
| 248 |
|
|
fp0_done = cnt > 8'd4;
|
| 249 |
|
|
`FDIV: fp0_done = cnt > 8'h70;
|
| 250 |
|
|
`FDIVS: fp0_done = cnt > 8'h37;
|
| 251 |
|
|
default: fp0_done = 1'b1;
|
| 252 |
|
|
endcase
|
| 253 |
|
|
`SINGLE_R:
|
| 254 |
|
|
case(fp0_fn)
|
| 255 |
|
|
`FNEGS,`FABSS,`FSIGNS,`FMOVS,
|
| 256 |
|
|
`FNABSS,`FMANS:
|
| 257 |
|
|
fp0_done = 1'b1; // These ops are done right away
|
| 258 |
|
|
`FTOIS,`ITOFS: fp0_done = cnt > 8'd1;
|
| 259 |
|
|
default: fp0_done = 1'b1;
|
| 260 |
|
|
endcase
|
| 261 |
|
|
`DOUBLE_R:
|
| 262 |
|
|
case(fp0_fn)
|
| 263 |
|
|
`FMOV,`FNEG,`FABS,`FNABS,`FSIGN,`FMAN:
|
| 264 |
|
|
fp0_done = 1'b1; // These ops are done right away
|
| 265 |
|
|
`FTOI,`ITOF: fp0_done = cnt > 8'd1;
|
| 266 |
|
|
default: fp0_done = 1'b1;
|
| 267 |
|
|
endcase
|
| 268 |
|
|
default: fp0_done = 1'b1;
|
| 269 |
|
|
endcase
|
| 270 |
|
|
end
|
| 271 |
|
|
|
| 272 |
|
|
assign fp0_cmt = fnPredicate(fp0_pred, fp0_cond);
|
| 273 |
|
|
assign fp0_exc = fp0_exception ? 8'd242 : 8'd0;
|
| 274 |
|
|
|
| 275 |
|
|
assign fp0_v = fp0_dataready;
|
| 276 |
|
|
assign fp0_id = fp0_sourceid;
|
| 277 |
|
|
`endif
|
| 278 |
|
|
|