diff options
Diffstat (limited to 'tests/asicworld/code_hdl_models_arbiter.v')
| -rw-r--r-- | tests/asicworld/code_hdl_models_arbiter.v | 246 |
1 files changed, 123 insertions, 123 deletions
diff --git a/tests/asicworld/code_hdl_models_arbiter.v b/tests/asicworld/code_hdl_models_arbiter.v index 978e1987..d3e3a66f 100644 --- a/tests/asicworld/code_hdl_models_arbiter.v +++ b/tests/asicworld/code_hdl_models_arbiter.v @@ -1,123 +1,123 @@ -//----------------------------------------------------
-// A four level, round-robin arbiter. This was
-// orginally coded by WD Peterson in VHDL.
-//----------------------------------------------------
-module arbiter (
- clk,
- rst,
- req3,
- req2,
- req1,
- req0,
- gnt3,
- gnt2,
- gnt1,
- gnt0
-);
-// --------------Port Declaration-----------------------
-input clk;
-input rst;
-input req3;
-input req2;
-input req1;
-input req0;
-output gnt3;
-output gnt2;
-output gnt1;
-output gnt0;
-
-//--------------Internal Registers----------------------
-wire [1:0] gnt ;
-wire comreq ;
-wire beg ;
-wire [1:0] lgnt ;
-wire lcomreq ;
-reg lgnt0 ;
-reg lgnt1 ;
-reg lgnt2 ;
-reg lgnt3 ;
-reg lasmask ;
-reg lmask0 ;
-reg lmask1 ;
-reg ledge ;
-
-//--------------Code Starts Here-----------------------
-always @ (posedge clk)
-if (rst) begin
- lgnt0 <= 0;
- lgnt1 <= 0;
- lgnt2 <= 0;
- lgnt3 <= 0;
-end else begin
- lgnt0 <=(~lcomreq & ~lmask1 & ~lmask0 & ~req3 & ~req2 & ~req1 & req0)
- | (~lcomreq & ~lmask1 & lmask0 & ~req3 & ~req2 & req0)
- | (~lcomreq & lmask1 & ~lmask0 & ~req3 & req0)
- | (~lcomreq & lmask1 & lmask0 & req0 )
- | ( lcomreq & lgnt0 );
- lgnt1 <=(~lcomreq & ~lmask1 & ~lmask0 & req1)
- | (~lcomreq & ~lmask1 & lmask0 & ~req3 & ~req2 & req1 & ~req0)
- | (~lcomreq & lmask1 & ~lmask0 & ~req3 & req1 & ~req0)
- | (~lcomreq & lmask1 & lmask0 & req1 & ~req0)
- | ( lcomreq & lgnt1);
- lgnt2 <=(~lcomreq & ~lmask1 & ~lmask0 & req2 & ~req1)
- | (~lcomreq & ~lmask1 & lmask0 & req2)
- | (~lcomreq & lmask1 & ~lmask0 & ~req3 & req2 & ~req1 & ~req0)
- | (~lcomreq & lmask1 & lmask0 & req2 & ~req1 & ~req0)
- | ( lcomreq & lgnt2);
- lgnt3 <=(~lcomreq & ~lmask1 & ~lmask0 & req3 & ~req2 & ~req1)
- | (~lcomreq & ~lmask1 & lmask0 & req3 & ~req2)
- | (~lcomreq & lmask1 & ~lmask0 & req3)
- | (~lcomreq & lmask1 & lmask0 & req3 & ~req2 & ~req1 & ~req0)
- | ( lcomreq & lgnt3);
-end
-
-//----------------------------------------------------
-// lasmask state machine.
-//----------------------------------------------------
-assign beg = (req3 | req2 | req1 | req0) & ~lcomreq;
-always @ (posedge clk)
-begin
- lasmask <= (beg & ~ledge & ~lasmask);
- ledge <= (beg & ~ledge & lasmask)
- | (beg & ledge & ~lasmask);
-end
-
-//----------------------------------------------------
-// comreq logic.
-//----------------------------------------------------
-assign lcomreq = ( req3 & lgnt3 )
- | ( req2 & lgnt2 )
- | ( req1 & lgnt1 )
- | ( req0 & lgnt0 );
-
-//----------------------------------------------------
-// Encoder logic.
-//----------------------------------------------------
-assign lgnt = {(lgnt3 | lgnt2),(lgnt3 | lgnt1)};
-
-//----------------------------------------------------
-// lmask register.
-//----------------------------------------------------
-always @ (posedge clk )
-if( rst ) begin
- lmask1 <= 0;
- lmask0 <= 0;
-end else if(lasmask) begin
- lmask1 <= lgnt[1];
- lmask0 <= lgnt[0];
-end else begin
- lmask1 <= lmask1;
- lmask0 <= lmask0;
-end
-
-assign comreq = lcomreq;
-assign gnt = lgnt;
-//----------------------------------------------------
-// Drive the outputs
-//----------------------------------------------------
-assign gnt3 = lgnt3;
-assign gnt2 = lgnt2;
-assign gnt1 = lgnt1;
-assign gnt0 = lgnt0;
-
-endmodule
+//---------------------------------------------------- +// A four level, round-robin arbiter. This was +// orginally coded by WD Peterson in VHDL. +//---------------------------------------------------- +module arbiter ( + clk, + rst, + req3, + req2, + req1, + req0, + gnt3, + gnt2, + gnt1, + gnt0 +); +// --------------Port Declaration----------------------- +input clk; +input rst; +input req3; +input req2; +input req1; +input req0; +output gnt3; +output gnt2; +output gnt1; +output gnt0; + +//--------------Internal Registers---------------------- +wire [1:0] gnt ; +wire comreq ; +wire beg ; +wire [1:0] lgnt ; +wire lcomreq ; +reg lgnt0 ; +reg lgnt1 ; +reg lgnt2 ; +reg lgnt3 ; +reg lasmask ; +reg lmask0 ; +reg lmask1 ; +reg ledge ; + +//--------------Code Starts Here----------------------- +always @ (posedge clk) +if (rst) begin + lgnt0 <= 0; + lgnt1 <= 0; + lgnt2 <= 0; + lgnt3 <= 0; +end else begin + lgnt0 <=(~lcomreq & ~lmask1 & ~lmask0 & ~req3 & ~req2 & ~req1 & req0) + | (~lcomreq & ~lmask1 & lmask0 & ~req3 & ~req2 & req0) + | (~lcomreq & lmask1 & ~lmask0 & ~req3 & req0) + | (~lcomreq & lmask1 & lmask0 & req0 ) + | ( lcomreq & lgnt0 ); + lgnt1 <=(~lcomreq & ~lmask1 & ~lmask0 & req1) + | (~lcomreq & ~lmask1 & lmask0 & ~req3 & ~req2 & req1 & ~req0) + | (~lcomreq & lmask1 & ~lmask0 & ~req3 & req1 & ~req0) + | (~lcomreq & lmask1 & lmask0 & req1 & ~req0) + | ( lcomreq & lgnt1); + lgnt2 <=(~lcomreq & ~lmask1 & ~lmask0 & req2 & ~req1) + | (~lcomreq & ~lmask1 & lmask0 & req2) + | (~lcomreq & lmask1 & ~lmask0 & ~req3 & req2 & ~req1 & ~req0) + | (~lcomreq & lmask1 & lmask0 & req2 & ~req1 & ~req0) + | ( lcomreq & lgnt2); + lgnt3 <=(~lcomreq & ~lmask1 & ~lmask0 & req3 & ~req2 & ~req1) + | (~lcomreq & ~lmask1 & lmask0 & req3 & ~req2) + | (~lcomreq & lmask1 & ~lmask0 & req3) + | (~lcomreq & lmask1 & lmask0 & req3 & ~req2 & ~req1 & ~req0) + | ( lcomreq & lgnt3); +end + +//---------------------------------------------------- +// lasmask state machine. +//---------------------------------------------------- +assign beg = (req3 | req2 | req1 | req0) & ~lcomreq; +always @ (posedge clk) +begin + lasmask <= (beg & ~ledge & ~lasmask); + ledge <= (beg & ~ledge & lasmask) + | (beg & ledge & ~lasmask); +end + +//---------------------------------------------------- +// comreq logic. +//---------------------------------------------------- +assign lcomreq = ( req3 & lgnt3 ) + | ( req2 & lgnt2 ) + | ( req1 & lgnt1 ) + | ( req0 & lgnt0 ); + +//---------------------------------------------------- +// Encoder logic. +//---------------------------------------------------- +assign lgnt = {(lgnt3 | lgnt2),(lgnt3 | lgnt1)}; + +//---------------------------------------------------- +// lmask register. +//---------------------------------------------------- +always @ (posedge clk ) +if( rst ) begin + lmask1 <= 0; + lmask0 <= 0; +end else if(lasmask) begin + lmask1 <= lgnt[1]; + lmask0 <= lgnt[0]; +end else begin + lmask1 <= lmask1; + lmask0 <= lmask0; +end + +assign comreq = lcomreq; +assign gnt = lgnt; +//---------------------------------------------------- +// Drive the outputs +//---------------------------------------------------- +assign gnt3 = lgnt3; +assign gnt2 = lgnt2; +assign gnt1 = lgnt1; +assign gnt0 = lgnt0; + +endmodule |