From e008d663f4b40e15be818120daa8646d3c5a558b Mon Sep 17 00:00:00 2001 From: David Harris Date: Wed, 16 Nov 2022 10:00:07 -0800 Subject: [PATCH 1/3] Moved DivStartE to fdivsqrtfsm --- pipelined/src/fpu/fctrl.sv | 10 ++++------ pipelined/src/fpu/fdivsqrt/fdivsqrt.sv | 5 +++-- pipelined/src/fpu/fdivsqrt/fdivsqrtfsm.sv | 17 +++++++++++++---- pipelined/src/fpu/fpu.sv | 6 +++--- 4 files changed, 23 insertions(+), 15 deletions(-) diff --git a/pipelined/src/fpu/fctrl.sv b/pipelined/src/fpu/fctrl.sv index dd291ecea..661d53cba 100755 --- a/pipelined/src/fpu/fctrl.sv +++ b/pipelined/src/fpu/fctrl.sv @@ -47,7 +47,7 @@ module fctrl ( output logic FRegWriteM, FRegWriteW, // FP register write enable output logic [2:0] FrmM, // FP rounding mode output logic [`FMTBITS-1:0] FmtE, FmtM, // FP format - output logic DivStartE, // Start division or squareroot + output logic FDivStartE, IDivStartE, // Start division or squareroot output logic XEnE, YEnE, ZEnE, output logic YEnForwardE, ZEnForwardE, output logic FWriteIntE, FCvtIntE, FWriteIntM, // Write to integer register @@ -62,7 +62,7 @@ module fctrl ( logic [`FCTRLW-1:0] ControlsD; logic IllegalFPUInstrD, IllegalFPUInstrE; logic FRegWriteD; // FP register write enable - logic FDivStartD, FDivStartE, IDivStartE; // integer register write enable + logic FDivStartD; // integer register write enable logic FWriteIntD; // integer register write enable logic FRegWriteE; // FP register write enable logic [2:0] OpCtrlD; // Select which opperation to do in each component @@ -266,10 +266,8 @@ module fctrl ( flopenrc #(15) DEAdrReg(clk, reset, FlushE, ~StallE, {InstrD[19:15], InstrD[24:20], InstrD[31:27]}, {Adr1E, Adr2E, Adr3E}); flopenrc #(1) DEFDivStartReg(clk, reset, FlushE, ~StallE|FDivBusyE, FDivStartD, FDivStartE); - if (`M_SUPPORTED) begin - assign IDivStartE = MDUE & Funct3E[2]; - assign DivStartE = FDivStartE | IDivStartE; // integer or floating-point division - end else assign DivStartE = FDivStartE; + if (`M_SUPPORTED) assign IDivStartE = MDUE & Funct3E[2]; + else assign IDivStartE = 0; assign FCvtIntE = (FResSelE == 2'b01); diff --git a/pipelined/src/fpu/fdivsqrt/fdivsqrt.sv b/pipelined/src/fpu/fdivsqrt/fdivsqrt.sv index 14e7cfa99..e675d3574 100644 --- a/pipelined/src/fpu/fdivsqrt/fdivsqrt.sv +++ b/pipelined/src/fpu/fdivsqrt/fdivsqrt.sv @@ -40,7 +40,7 @@ module fdivsqrt( input logic XInfE, YInfE, input logic XZeroE, YZeroE, input logic XNaNE, YNaNE, - input logic DivStartE, + input logic FDivStartE, IDivStartE, input logic StallM, input logic StallE, input logic SqrtE, SqrtM, @@ -66,6 +66,7 @@ module fdivsqrt( logic SpecialCaseM; logic [`DIVBLEN:0] n, m; logic OTFCSwap, ALTB, BZero, As; + logic DivStartE; fdivsqrtpreproc fdivsqrtpreproc( .clk, .DivStartE, .Xm(XmE), .QeM, .Xe(XeE), .Fmt(FmtE), .Ye(YeE), @@ -74,7 +75,7 @@ module fdivsqrt( .ForwardedSrcAE, .ForwardedSrcBE, .Funct3E, .Funct3M, .MDUE, .W64E); fdivsqrtfsm fdivsqrtfsm( .clk, .reset, .FmtE, .XsE, .SqrtE, - .DivBusy, .DivStartE,.StallE, .StallM, .DivDone, .XZeroE, .YZeroE, + .DivBusy, .FDivStartE, .IDivStartE, .DivStartE, .StallE, .StallM, .DivDone, .XZeroE, .YZeroE, .XNaNE, .YNaNE, .MDUE, .n, .XInfE, .YInfE, .WZero, .SpecialCaseM); fdivsqrtiter fdivsqrtiter( diff --git a/pipelined/src/fpu/fdivsqrt/fdivsqrtfsm.sv b/pipelined/src/fpu/fdivsqrt/fdivsqrtfsm.sv index 9222c0c4f..03f519049 100644 --- a/pipelined/src/fpu/fdivsqrt/fdivsqrtfsm.sv +++ b/pipelined/src/fpu/fdivsqrt/fdivsqrtfsm.sv @@ -37,7 +37,7 @@ module fdivsqrtfsm( input logic XInfE, YInfE, input logic XZeroE, YZeroE, input logic XNaNE, YNaNE, - input logic DivStartE, + input logic FDivStartE, IDivStartE, input logic XsE, input logic SqrtE, input logic StallE, @@ -45,6 +45,7 @@ module fdivsqrtfsm( input logic WZero, input logic MDUE, input logic [`DIVBLEN:0] n, + output logic DivStartE, output logic DivDone, output logic DivBusy, output logic SpecialCaseM @@ -57,6 +58,17 @@ module fdivsqrtfsm( logic [`DURLEN-1:0] cycles; logic SpecialCaseE; + // *** start logic is presently in fctl. Make it look more like integer division start logic + // DivStartE comes from fctrl, reflecitng the start of floating-point and possibly integer division + assign DivStartE = (FDivStartE | IDivStartE); // & (state == IDLE) & ~StallM; + //assign DivStartE = (FDivStartE | IDivStartE) & (state == IDLE) & ~StallM; + assign DivDone = (state == DONE) | (WZero & (state == BUSY)); + assign DivBusy = (state == BUSY & ~DivDone); + + // Divider control signals from MDU + //assign DivStartE = DivE & (state == IDLE) & ~StallM; + //assign DivBusyE = (state == BUSY) | DivStartE; + // terminate immediately on special cases assign SpecialCaseE = XZeroE | (YZeroE&~SqrtE) | XInfE | YInfE | XNaNE | YNaNE | (XsE&SqrtE); flopenr #(1) SpecialCaseReg(clk, reset, ~StallM, SpecialCaseE, SpecialCaseM); // save SpecialCase for checking in fdivsqrtpostproc @@ -120,8 +132,5 @@ module fdivsqrtfsm( end end - // *** start logic is presently in fctl. Make it look more like integer division start logic - assign DivDone = (state == DONE) | (WZero & (state == BUSY)); - assign DivBusy = (state == BUSY & ~DivDone); endmodule \ No newline at end of file diff --git a/pipelined/src/fpu/fpu.sv b/pipelined/src/fpu/fpu.sv index dcc0db6d5..2f6dcce5a 100755 --- a/pipelined/src/fpu/fpu.sv +++ b/pipelined/src/fpu/fpu.sv @@ -67,7 +67,7 @@ module fpu ( logic FRegWriteW; // FP register write enable logic [2:0] FrmM; // FP rounding mode logic [`FMTBITS-1:0] FmtE, FmtM; // FP precision 0-single 1-double - logic DivStartE; // Start division or squareroot + logic FDivStartE, IDivStartE; // Start division or squareroot logic FWriteIntM; // Write to integer register logic [1:0] ForwardXE, ForwardYE, ForwardZE; // forwarding mux control signals logic [2:0] OpCtrlE, OpCtrlM; // Select which opperation to do in each component @@ -167,7 +167,7 @@ module fpu ( .Funct3E, .MDUE, .InstrD, .StallE, .StallM, .StallW, .FlushE, .FlushM, .FlushW, .FRM_REGW, .STATUS_FS, .FDivBusyE, .reset, .clk, .FRegWriteM, .FRegWriteW, .FrmM, .FmtE, .FmtM, .YEnForwardE, .ZEnForwardE, - .DivStartE, .FWriteIntE, .FCvtIntE, .FWriteIntM, .OpCtrlE, .OpCtrlM, .IllegalFPUInstrM, .XEnE, .YEnE, .ZEnE, + .FDivStartE, .IDivStartE, .FWriteIntE, .FCvtIntE, .FWriteIntM, .OpCtrlE, .OpCtrlM, .IllegalFPUInstrM, .XEnE, .YEnE, .ZEnE, .FResSelE, .FResSelM, .FResSelW, .PostProcSelE, .PostProcSelM, .FCvtIntW, .Adr1E, .Adr2E, .Adr3E); // FP register file @@ -261,7 +261,7 @@ module fpu ( // - fsqrt // *** add other opperations fdivsqrt fdivsqrt(.clk, .reset, .FmtE, .XmE, .YmE, .XeE, .YeE, .SqrtE(OpCtrlE[0]), .SqrtM(OpCtrlM[0]), - .XInfE, .YInfE, .XZeroE, .YZeroE, .XNaNE, .YNaNE, .DivStartE(DivStartE), .XsE, + .XInfE, .YInfE, .XZeroE, .YZeroE, .XNaNE, .YNaNE, .FDivStartE, .IDivStartE, .XsE, .ForwardedSrcAE, .ForwardedSrcBE, .Funct3E, .Funct3M, .MDUE, .W64E, .StallE, .StallM, .DivSM, .DivBusy(FDivBusyE), .QeM, //***change divbusyE to M signal .QmM, .DivDone(DivDoneM)); From ddba68605ebc7932337a6d74f30e79144ef434ac Mon Sep 17 00:00:00 2001 From: David Harris Date: Wed, 16 Nov 2022 10:13:27 -0800 Subject: [PATCH 2/3] Renamed DivBusy to FDivBusyE in FPU --- pipelined/src/fpu/fdivsqrt/fdivsqrt.sv | 6 +++--- pipelined/src/fpu/fdivsqrt/fdivsqrtfsm.sv | 8 +++----- pipelined/src/fpu/fdivsqrt/fdivsqrtiter.sv | 12 ++++++------ pipelined/src/fpu/fpu.sv | 2 +- 4 files changed, 13 insertions(+), 15 deletions(-) diff --git a/pipelined/src/fpu/fdivsqrt/fdivsqrt.sv b/pipelined/src/fpu/fdivsqrt/fdivsqrt.sv index e675d3574..9bb9117c7 100644 --- a/pipelined/src/fpu/fdivsqrt/fdivsqrt.sv +++ b/pipelined/src/fpu/fdivsqrt/fdivsqrt.sv @@ -48,7 +48,7 @@ module fdivsqrt( input logic [2:0] Funct3E, Funct3M, input logic MDUE, W64E, output logic DivSM, - output logic DivBusy, + output logic FDivBusyE, output logic DivDone, output logic [`NE+1:0] QeM, output logic [`DIVb:0] QmM @@ -75,14 +75,14 @@ module fdivsqrt( .ForwardedSrcAE, .ForwardedSrcBE, .Funct3E, .Funct3M, .MDUE, .W64E); fdivsqrtfsm fdivsqrtfsm( .clk, .reset, .FmtE, .XsE, .SqrtE, - .DivBusy, .FDivStartE, .IDivStartE, .DivStartE, .StallE, .StallM, .DivDone, .XZeroE, .YZeroE, + .FDivBusyE, .FDivStartE, .IDivStartE, .DivStartE, .StallE, .StallM, .DivDone, .XZeroE, .YZeroE, .XNaNE, .YNaNE, .MDUE, .n, .XInfE, .YInfE, .WZero, .SpecialCaseM); fdivsqrtiter fdivsqrtiter( .clk, .Firstun, .D, .FirstU, .FirstUM, .FirstC, .SqrtE, .SqrtM, .X,.Dpreproc, .FirstWS(WS), .FirstWC(WC), .DivStartE, .Xe(XeE), .Ye(YeE), .XZeroE, .YZeroE, .OTFCSwap, - .DivBusy); + .FDivBusyE); fdivsqrtpostproc fdivsqrtpostproc( .WS, .WC, .D, .FirstU, .FirstUM, .FirstC, .Firstun, .SqrtM, .SpecialCaseM, .RemOp(Funct3E[1]), diff --git a/pipelined/src/fpu/fdivsqrt/fdivsqrtfsm.sv b/pipelined/src/fpu/fdivsqrt/fdivsqrtfsm.sv index 03f519049..2c7a7947d 100644 --- a/pipelined/src/fpu/fdivsqrt/fdivsqrtfsm.sv +++ b/pipelined/src/fpu/fdivsqrt/fdivsqrtfsm.sv @@ -47,7 +47,7 @@ module fdivsqrtfsm( input logic [`DIVBLEN:0] n, output logic DivStartE, output logic DivDone, - output logic DivBusy, + output logic FDivBusyE, output logic SpecialCaseM ); @@ -60,13 +60,11 @@ module fdivsqrtfsm( // *** start logic is presently in fctl. Make it look more like integer division start logic // DivStartE comes from fctrl, reflecitng the start of floating-point and possibly integer division - assign DivStartE = (FDivStartE | IDivStartE); // & (state == IDLE) & ~StallM; - //assign DivStartE = (FDivStartE | IDivStartE) & (state == IDLE) & ~StallM; + assign DivStartE = (FDivStartE | IDivStartE) & (state == IDLE) & ~StallM; assign DivDone = (state == DONE) | (WZero & (state == BUSY)); - assign DivBusy = (state == BUSY & ~DivDone); + assign FDivBusyE = (state == BUSY & ~DivDone); // Divider control signals from MDU - //assign DivStartE = DivE & (state == IDLE) & ~StallM; //assign DivBusyE = (state == BUSY) | DivStartE; // terminate immediately on special cases diff --git a/pipelined/src/fpu/fdivsqrt/fdivsqrtiter.sv b/pipelined/src/fpu/fdivsqrt/fdivsqrtiter.sv index 4df7a1472..a6c6c8bce 100644 --- a/pipelined/src/fpu/fdivsqrt/fdivsqrtiter.sv +++ b/pipelined/src/fpu/fdivsqrt/fdivsqrtiter.sv @@ -33,7 +33,7 @@ module fdivsqrtiter( input logic clk, input logic DivStartE, - input logic DivBusy, + input logic FDivBusyE, input logic [`NE-1:0] Xe, Ye, input logic XZeroE, YZeroE, input logic SqrtE, @@ -85,8 +85,8 @@ module fdivsqrtiter( // Residual WS/SC registers/initializaiton mux mux2 #(`DIVb+4) wsmux(WS[`DIVCOPIES], X, DivStartE, WSN); mux2 #(`DIVb+4) wcmux(WC[`DIVCOPIES], '0, DivStartE, WCN); - flopen #(`DIVb+4) wsflop(clk, DivStartE|DivBusy, WSN, WS[0]); - flopen #(`DIVb+4) wcflop(clk, DivStartE|DivBusy, WCN, WC[0]); + flopen #(`DIVb+4) wsflop(clk, DivStartE|FDivBusyE, WSN, WS[0]); + flopen #(`DIVb+4) wcflop(clk, DivStartE|FDivBusyE, WCN, WC[0]); // UOTFC Result U and UM registers/initialization mux // Initialize U to 1.0 and UM to 0 for square root; U to 0 and UM to -1 for division @@ -94,8 +94,8 @@ module fdivsqrtiter( assign initUM = SqrtE ? 0 : {1'b1, {(`DIVb){1'b0}}}; mux2 #(`DIVb+1) Umux(UNext[`DIVCOPIES-1], initU, DivStartE, UMux); mux2 #(`DIVb+1) UMmux(UMNext[`DIVCOPIES-1], initUM, DivStartE, UMMux); - flopen #(`DIVb+1) UReg(clk, DivStartE|DivBusy, UMux, U[0]); - flopen #(`DIVb+1) UMReg(clk, DivStartE|DivBusy, UMMux, UM[0]); + flopen #(`DIVb+1) UReg(clk, DivStartE|FDivBusyE, UMux, U[0]); + flopen #(`DIVb+1) UMReg(clk, DivStartE|FDivBusyE, UMMux, UM[0]); // C register/initialization mux // Initialize C to -1 for sqrt and -R for division @@ -103,7 +103,7 @@ module fdivsqrtiter( assign initCUpper = SqrtE ? 2'b11 : (`RADIX == 4) ? 2'b00 : 2'b10; assign initC = {initCUpper, {`DIVb{1'b0}}}; mux2 #(`DIVb+2) Cmux(C[`DIVCOPIES], initC, DivStartE, CMux); - flopen #(`DIVb+2) cflop(clk, DivStartE|DivBusy, CMux, C[0]); + flopen #(`DIVb+2) cflop(clk, DivStartE|FDivBusyE, CMux, C[0]); // Divisior register flopen #(`DIVN-1) dflop(clk, DivStartE, Dpreproc, D); diff --git a/pipelined/src/fpu/fpu.sv b/pipelined/src/fpu/fpu.sv index 2f6dcce5a..d0b4aceef 100755 --- a/pipelined/src/fpu/fpu.sv +++ b/pipelined/src/fpu/fpu.sv @@ -263,7 +263,7 @@ module fpu ( fdivsqrt fdivsqrt(.clk, .reset, .FmtE, .XmE, .YmE, .XeE, .YeE, .SqrtE(OpCtrlE[0]), .SqrtM(OpCtrlM[0]), .XInfE, .YInfE, .XZeroE, .YZeroE, .XNaNE, .YNaNE, .FDivStartE, .IDivStartE, .XsE, .ForwardedSrcAE, .ForwardedSrcBE, .Funct3E, .Funct3M, .MDUE, .W64E, - .StallE, .StallM, .DivSM, .DivBusy(FDivBusyE), .QeM, //***change divbusyE to M signal + .StallE, .StallM, .DivSM, .FDivBusyE, .QeM, .QmM, .DivDone(DivDoneM)); // From bc3b78354306c7ed00e0236a0854099fa28564a7 Mon Sep 17 00:00:00 2001 From: David Harris Date: Wed, 16 Nov 2022 10:23:20 -0800 Subject: [PATCH 3/3] comment cleanup --- pipelined/src/fpu/fdivsqrt/fdivsqrtfsm.sv | 4 ++-- pipelined/src/fpu/postproc/postprocess.sv | 2 +- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/pipelined/src/fpu/fdivsqrt/fdivsqrtfsm.sv b/pipelined/src/fpu/fdivsqrt/fdivsqrtfsm.sv index 2c7a7947d..e33688500 100644 --- a/pipelined/src/fpu/fdivsqrt/fdivsqrtfsm.sv +++ b/pipelined/src/fpu/fdivsqrt/fdivsqrtfsm.sv @@ -61,8 +61,8 @@ module fdivsqrtfsm( // *** start logic is presently in fctl. Make it look more like integer division start logic // DivStartE comes from fctrl, reflecitng the start of floating-point and possibly integer division assign DivStartE = (FDivStartE | IDivStartE) & (state == IDLE) & ~StallM; - assign DivDone = (state == DONE) | (WZero & (state == BUSY)); - assign FDivBusyE = (state == BUSY & ~DivDone); + assign DivDone = (state == DONE) | (WZero & (state == BUSY)); // *** used in postprocess.sv and round.sv. This doesn't seem proper. They break when removed. + assign FDivBusyE = (state == BUSY & ~DivDone); // *** want to add | DivStartE but it creates comb loop // Divider control signals from MDU //assign DivBusyE = (state == BUSY) | DivStartE; diff --git a/pipelined/src/fpu/postproc/postprocess.sv b/pipelined/src/fpu/postproc/postprocess.sv index ee18c4bcd..24365cf96 100644 --- a/pipelined/src/fpu/postproc/postprocess.sv +++ b/pipelined/src/fpu/postproc/postprocess.sv @@ -129,7 +129,7 @@ module postprocess ( assign Mult = OpCtrl[2]&~OpCtrl[1]&~OpCtrl[0]; assign CvtOp = (PostProcSel == 2'b00); assign FmaOp = (PostProcSel == 2'b10); - assign DivOp = (PostProcSel == 2'b01)&DivDone; + assign DivOp = (PostProcSel == 2'b01) & DivDone; assign Sqrt = OpCtrl[0]; // is there an input of infinity or NaN being used