writeback refactoring

This commit is contained in:
Blaise Tine
2021-07-26 11:25:30 -07:00
parent 1ba2a10ad8
commit 15e4d8b716

View File

@@ -17,11 +17,8 @@ module VX_writeback #(
);
`UNUSED_PARAM (CORE_ID)
wire ld_valid = ld_commit_if.valid && ld_commit_if.wb;
wire fpu_valid = fpu_commit_if.valid && fpu_commit_if.wb;
wire csr_valid = csr_commit_if.valid && csr_commit_if.wb;
wire alu_valid = alu_commit_if.valid && alu_commit_if.wb;
localparam DATAW = `NW_BITS + 32 + `NUM_THREADS + `NR_BITS + (`NUM_THREADS * 32) + 1;
wire wb_valid;
wire [`NW_BITS-1:0] wb_wid;
@@ -30,60 +27,54 @@ module VX_writeback #(
wire [`NR_BITS-1:0] wb_rd;
wire [`NUM_THREADS-1:0][31:0] wb_data;
wire wb_eop;
wire [3:0][DATAW-1:0] rsp_data;
wire [3:0] rsp_ready;
wire stall;
assign wb_valid = ld_valid |
fpu_valid |
csr_valid |
alu_valid;
wire ld_valid = ld_commit_if.valid && ld_commit_if.wb;
wire fpu_valid = fpu_commit_if.valid && fpu_commit_if.wb;
wire csr_valid = csr_commit_if.valid && csr_commit_if.wb;
wire alu_valid = alu_commit_if.valid && alu_commit_if.wb;
assign wb_wid = ld_valid ? ld_commit_if.wid :
fpu_valid ? fpu_commit_if.wid :
csr_valid ? csr_commit_if.wid :
/*alu_valid ?*/ alu_commit_if.wid;
assign wb_PC = ld_valid ? ld_commit_if.PC :
fpu_valid ? fpu_commit_if.PC :
csr_valid ? csr_commit_if.PC :
/*alu_valid ?*/ alu_commit_if.PC;
assign rsp_data[0] = { ld_commit_if.wid, ld_commit_if.PC, ld_commit_if.tmask, ld_commit_if.rd, ld_commit_if.data, ld_commit_if.eop};
assign rsp_data[1] = {fpu_commit_if.wid, fpu_commit_if.PC, fpu_commit_if.tmask, fpu_commit_if.rd, fpu_commit_if.data, fpu_commit_if.eop};
assign rsp_data[2] = {csr_commit_if.wid, csr_commit_if.PC, csr_commit_if.tmask, csr_commit_if.rd, csr_commit_if.data, csr_commit_if.eop};
assign rsp_data[3] = {alu_commit_if.wid, alu_commit_if.PC, alu_commit_if.tmask, alu_commit_if.rd, alu_commit_if.data, alu_commit_if.eop};
assign wb_tmask = ld_valid ? ld_commit_if.tmask :
fpu_valid ? fpu_commit_if.tmask :
csr_valid ? csr_commit_if.tmask :
/*alu_valid ?*/ alu_commit_if.tmask;
VX_stream_arbiter #(
.NUM_REQS (4),
.DATAW (DATAW),
.TYPE ("X")
) rsp_arb (
.clk (clk),
.reset (reset),
.valid_in ({alu_valid, csr_valid, fpu_valid, ld_valid}),
.data_in (rsp_data),
.ready_in (rsp_ready),
.valid_out (wb_valid),
.data_out ({wb_wid, wb_PC, wb_tmask, wb_rd, wb_data, wb_eop}),
.ready_out (~stall)
);
assign wb_rd = ld_valid ? ld_commit_if.rd :
fpu_valid ? fpu_commit_if.rd :
csr_valid ? csr_commit_if.rd :
/*alu_valid ?*/ alu_commit_if.rd;
assign ld_commit_if.ready = rsp_ready[0] || ~ld_commit_if.wb;
assign fpu_commit_if.ready = rsp_ready[1] || ~fpu_commit_if.wb;
assign csr_commit_if.ready = rsp_ready[2] || ~csr_commit_if.wb;
assign alu_commit_if.ready = rsp_ready[3] || ~alu_commit_if.wb;
assign wb_data = ld_valid ? ld_commit_if.data :
fpu_valid ? fpu_commit_if.data :
csr_valid ? csr_commit_if.data :
/*alu_valid ?*/ alu_commit_if.data;
assign wb_eop = ld_valid ? ld_commit_if.eop :
fpu_valid ? fpu_commit_if.eop :
csr_valid ? csr_commit_if.eop :
/*alu_valid ?*/ alu_commit_if.eop;
wire stall = ~writeback_if.ready && writeback_if.valid;
assign stall = ~writeback_if.ready && writeback_if.valid;
VX_pipe_register #(
.DATAW (1 + `NW_BITS + 32 + `NUM_THREADS + `NR_BITS + (`NUM_THREADS * 32) + 1),
.DATAW (1 + DATAW),
.RESETW (1)
) pipe_reg (
.clk (clk),
.reset (reset),
.enable (!stall),
.enable (~stall),
.data_in ({wb_valid, wb_wid, wb_PC, wb_tmask, wb_rd, wb_data, wb_eop}),
.data_out ({writeback_if.valid, writeback_if.wid, writeback_if.PC, writeback_if.tmask, writeback_if.rd, writeback_if.data, writeback_if.eop})
);
assign ld_commit_if.ready = !(ld_commit_if.wb && (stall));
assign fpu_commit_if.ready = !(fpu_commit_if.wb && (stall || ld_valid));
assign csr_commit_if.ready = !(csr_commit_if.wb && (stall || ld_valid || fpu_valid));
assign alu_commit_if.ready = !(alu_commit_if.wb && (stall || ld_valid || fpu_valid || csr_valid));
// special workaround to get RISC-V tests Pass/Fail status
reg [31:0] last_wb_value [`NUM_REGS-1:0] /* verilator public */;
always @(posedge clk) begin