Memory: Instrument LDMSTM. Do not write back if writeback not requested. Comment...

[firearm.git] / Memory.v

diff --git a/Memory.v b/Memory.v
index eb4006f5884d3c71ccd7a5e20959a4238a2d4622..54032753da9e338397b336d4a307012275bd86b3 100644 (file)
--- a/Memory.v
+++ b/Memory.v
@@ -23,7 +23,7 @@ module Memory(
        output reg cp_req,
        input cp_ack,
        input cp_busy,
-       output cp_rnw,  /* 1 = read from CP, 0 = write to CP */
+       output reg cp_rnw,      /* 1 = read from CP, 0 = write to CP */
        input [31:0] cp_read,
        output reg [31:0] cp_write,
        
@@ -57,10 +57,10 @@ module Memory(
        reg [3:0] next_regsel, cur_reg, prev_reg;
        reg next_writeback;
 
-       wire next_outbubble;    
-       wire next_write_reg;
-       wire [3:0] next_write_num;
-       wire [31:0] next_write_data;
+       reg next_outbubble;     
+       reg next_write_reg;
+       reg [3:0] next_write_num;
+       reg [31:0] next_write_data;
 
        reg [1:0] lsr_state = 2'b01, next_lsr_state;
        reg [31:0] align_s1, align_s2, align_rddata;
@@ -216,7 +216,7 @@ module Memory(
                        next_outbubble = rw_wait;
                        outstall = rw_wait;
                        addr = insn[23] ? op0 + op1 : op0 - op1; /* up/down select */
-                       raddr = insn[24] ? op0 : addr; /* pre/post increment */
+                       raddr = insn[24] ? addr : op0; /* pre/post increment */
                        busaddr = raddr;
                        /* rotate to correct position */
                        align_s1 = raddr[1] ? {rd_data[15:0], rd_data[31:16]} : rd_data;
@@ -244,7 +244,7 @@ module Memory(
                                next_write_reg = 1'b1;
                                next_write_num = insn[19:16];
                                next_write_data = addr;
-                               next_lsr_state = 2'b10;
+                               next_lsr_state = 2'b01;
                        end
                        default: begin end
                        endcase
@@ -258,8 +258,9 @@ module Memory(
                        3'b001: begin
 //                             next_regs = insn[23] ? op1[15:0] : op1[0:15];
                                /** verilator can suck my dick */
-                               next_regs = insn[23] ? op1[15:0] : {op1[0], op1[1], op1[2], op1[3], op1[4], op1[5], op1[6], op1[7],
-                                                                   op1[8], op1[9], op1[10], op1[11], op1[12], op1[13], op1[14], op1[15]};
+                               $display("LDMSTM: Round 1: base register: %08x, reg list %b", op0, op1[15:0]);
+                               next_regs = insn[23] /* U */ ? op1[15:0] : {op1[0], op1[1], op1[2], op1[3], op1[4], op1[5], op1[6], op1[7],
+                                                                           op1[8], op1[9], op1[10], op1[11], op1[12], op1[13], op1[14], op1[15]};
                                offset = 6'b0;
                                outstall = 1'b1;
                                next_lsm_state = 3'b010;
@@ -337,7 +338,7 @@ module Memory(
                                        next_regs = 16'b0;
                                end
                                endcase
-                               cur_reg = insn[23] ? 4'hF - cur_reg : cur_reg;
+                               cur_reg = insn[23] ? cur_reg : 4'hF - cur_reg;
                                if(cur_reg == 4'hF && insn[22]) begin
                                        next_outcpsr = spsr;
                                end
@@ -359,8 +360,10 @@ module Memory(
                                end
 
                                st_read = cur_reg;
-                               wr_data = st_data;
+                               wr_data = (cur_reg == 4'hF) ? (pc + 12) : st_data;
                                busaddr = raddr;
+                               
+                               $display("LDMSTM: Stage 2: Writing: reg %d, wr_data %08x, addr %08x", cur_reg, wr_data, busaddr);
 
                                outstall = 1'b1;
 
@@ -369,7 +372,7 @@ module Memory(
                                end
                        end
                        3'b100: begin
-                               next_write_reg = 1'b1;
+                               next_write_reg = insn[21] /* writeback */;
                                next_write_num = insn[19:16];
                                next_write_data = insn[23] ? op0 + {26'b0, prev_offset} : op0 - {26'b0, prev_offset};
                                next_lsm_state = 3'b001;