X-Git-Url: http://git.joshuawise.com/firearm.git/blobdiff_plain/a02ca509af0305e3c94127433b47efe39c25c88f..979f2bd7aca637e8e546ec2675bef82c353b9aea:/Memory.v

diff --git a/Memory.v b/Memory.v
index 9c010e7..04220ca 100644
--- a/Memory.v
+++ b/Memory.v
@@ -16,12 +16,18 @@ module Memory(
 	output reg [3:0] st_read,
 	input [31:0] st_data,
 	
+	/* Coprocessor interface */
+	output reg cp_req,
+	input cp_ack,
+	input cp_busy,
+	
 	/* stage inputs */
 	input inbubble,
 	input [31:0] pc,
 	input [31:0] insn,
-	input [31:0] base,
-	input [31:0] offset,
+	input [31:0] op0,
+	input [31:0] op1,
+	input [31:0] op2,
 	input write_reg,
 	input [3:0] write_num,
 	input [31:0] write_data,
@@ -37,14 +43,18 @@ module Memory(
 	);
 
 	reg [31:0] addr, raddr, next_regdata;
-	reg [3:0] next_regsel;
+	reg [3:0] next_regsel, cur_reg, prev_reg;
 	reg next_writeback, next_notdone, next_inc_next;
 	reg [31:0] align_s1, align_s2, align_rddata;
-	
+
+	wire next_outbubble;	
 	wire next_write_reg;
 	wire [3:0] next_write_num;
 	wire [31:0] next_write_data;
 
+	reg [15:0] regs, next_regs;
+	reg started = 1'b0, next_started;
+
 	reg notdone = 1'b0;
 	reg inc_next = 1'b0;
 
@@ -52,12 +62,15 @@ module Memory(
 	begin
 		outpc <= pc;
 		outinsn <= insn;
-		outbubble <= rw_wait;
-		out_write_reg <= next_writeback;
-		out_write_num <= next_regsel;
-		out_write_data <= next_regdata;
+		outbubble <= next_outbubble;
+		out_write_reg <= next_write_reg;
+		out_write_num <= next_write_num;
+		out_write_data <= next_write_data;
 		notdone <= next_notdone;
 		inc_next <= next_inc_next;
+		regs <= next_regs;
+		prev_reg <= cur_reg;
+		started <= next_started;
 	end
 
 	always @(*)
@@ -74,17 +87,22 @@ module Memory(
 		next_write_num = write_num;
 		next_write_data = write_data;
 		next_inc_next = 1'b0;
+		next_outbubble = inbubble;
 		outstall = 1'b0;
-		
+		next_regs = 16'b0;
+		next_started = started;
+		cp_req = 1'b0;
+
 		casez(insn)
 		`DECODE_LDRSTR_UNDEFINED: begin end
 		`DECODE_LDRSTR: begin
 			if (!inbubble) begin
+				next_outbubble = rw_wait;
 				outstall = rw_wait | notdone;
 			
-				addr = insn[23] ? base + offset : base - offset; /* up/down select */
-				raddr = insn[24] ? base : addr;
-				busaddr = {raddr[31:2], 2'b0}; /* pre/post increment */
+				addr = insn[23] ? op0 + op1 : op0 - op1; /* up/down select */
+				raddr = insn[24] ? op0 : addr; /* pre/post increment */
+				busaddr = {raddr[31:2], 2'b0};
 				rd_req = insn[20];
 				wr_req = ~insn[20];
 				
@@ -95,8 +113,7 @@ module Memory(
 				align_rddata = insn[22] ? {24'b0, align_s2[7:0]} : align_s2;
 				
 				if(!insn[20]) begin
-					st_read = insn[15:12];
-					wr_data = insn[22] ? {4{st_data[7:0]}} : st_data; /* XXX need to actually store just a byte */
+					wr_data = insn[22] ? {4{op2[7:0]}} : op2; /* XXX need to actually store just a byte */
 				end
 				else if(!inc_next) begin
 					next_write_reg = 1'b1;
@@ -113,6 +130,98 @@ module Memory(
 			end
 		end
 		`DECODE_LDMSTM: begin
+			rd_req = insn[20];
+			wr_req = ~insn[20];
+			if(!started) begin
+				next_regs = op1[15:0];
+				next_started = 1'b1;
+			end
+			else if(inc_next) begin
+				if(insn[21]) begin
+					next_write_reg = 1'b1;
+					next_write_num = insn[19:16];
+					next_write_data = op0;
+				end
+				next_started = 1'b0;
+			end
+			else if(rw_wait) begin
+				next_regs = regs;
+				cur_reg = prev_reg;
+			end
+			else begin
+				casez(regs)
+				16'b???????????????1: begin
+					cur_reg = 4'h0;
+					next_regs = regs & 16'b1111111111111110;
+				end
+				16'b??????????????10: begin
+					cur_reg = 4'h1;
+					next_regs = regs & 16'b1111111111111100;
+				end
+				16'b?????????????100: begin
+					cur_reg = 4'h2;
+					next_regs = regs & 16'b1111111111111000;
+				end
+				16'b????????????1000: begin
+					cur_reg = 4'h3;
+					next_regs = regs & 16'b1111111111110000;
+				end
+				16'b???????????10000: begin
+					cur_reg = 4'h4;
+					next_regs = regs & 16'b1111111111100000;
+				end
+				16'b??????????100000: begin
+					cur_reg = 4'h5;
+					next_regs = regs & 16'b1111111111000000;
+				end
+				16'b?????????1000000: begin
+					cur_reg = 4'h6;
+					next_regs = regs & 16'b1111111110000000;
+				end
+				16'b????????10000000: begin
+					cur_reg = 4'h7;
+					next_regs = regs & 16'b1111111100000000;
+				end
+				16'b???????100000000: begin
+					cur_reg = 4'h8;
+					next_regs = regs & 16'b1111111000000000;
+				end
+				16'b??????1000000000: begin
+					cur_reg = 4'h9;
+					next_regs = regs & 16'b1111110000000000;
+				end
+				16'b?????10000000000: begin
+					cur_reg = 4'hA;
+					next_regs = regs & 16'b1111100000000000;
+				end
+				16'b????100000000000: begin
+					cur_reg = 4'hB;
+					next_regs = regs & 16'b1111000000000000;
+				end
+				16'b???1000000000000: begin
+					cur_reg = 4'hC;
+					next_regs = regs & 16'b1110000000000000;
+				end
+				16'b??10000000000000: begin
+					cur_reg = 4'hD;
+					next_regs = regs & 16'b1100000000000000;
+				end
+				16'b?100000000000000: begin
+					cur_reg = 4'hE;
+					next_regs = regs & 16'b1000000000000000;
+				end
+				16'b1000000000000000: begin
+					cur_reg = 4'hF;
+					next_regs = 16'b0;
+				end
+				default: begin
+					cur_reg = 4'hx;
+					next_regs = 16'b0;
+				end
+				endcase
+				next_inc_next = next_regs == 16'b0;
+				next_notdone = ~next_inc_next | (rw_wait & insn[20] & insn[21]);
+			end
 		end
 		default: begin end
 		endcase