verilog/rtl/user_project/ibex/ibex_load_store_unit.v

module ibex_load_store_unit (
	clk_i,
	rst_ni,
	data_req_o,
	data_gnt_i,
	data_rvalid_i,
	data_err_i,
	data_pmp_err_i,
	data_addr_o,
	data_we_o,
	data_be_o,
	data_wdata_o,
	data_rdata_i,
	lsu_we_i,
	lsu_type_i,
	lsu_wdata_i,
	lsu_sign_ext_i,
	lsu_rdata_o,
	lsu_rdata_valid_o,
	lsu_req_i,
	adder_result_ex_i,
	addr_incr_req_o,
	addr_last_o,
	lsu_req_done_o,
	lsu_resp_valid_o,
	load_err_o,
	store_err_o,
	busy_o,
	perf_load_o,
	perf_store_o
);
	input wire clk_i;
	input wire rst_ni;
	output reg data_req_o;
	input wire data_gnt_i;
	input wire data_rvalid_i;
	input wire data_err_i;
	input wire data_pmp_err_i;
	output wire [31:0] data_addr_o;
	output wire data_we_o;
	output wire [3:0] data_be_o;
	output wire [31:0] data_wdata_o;
	input wire [31:0] data_rdata_i;
	input wire lsu_we_i;
	input wire [1:0] lsu_type_i;
	input wire [31:0] lsu_wdata_i;
	input wire lsu_sign_ext_i;
	output wire [31:0] lsu_rdata_o;
	output wire lsu_rdata_valid_o;
	input wire lsu_req_i;
	input wire [31:0] adder_result_ex_i;
	output reg addr_incr_req_o;
	output wire [31:0] addr_last_o;
	output wire lsu_req_done_o;
	output wire lsu_resp_valid_o;
	output wire load_err_o;
	output wire store_err_o;
	output wire busy_o;
	output reg perf_load_o;
	output reg perf_store_o;
	wire [31:0] data_addr;
	wire [31:0] data_addr_w_aligned;
	reg [31:0] addr_last_q;
	reg addr_update;
	reg ctrl_update;
	reg rdata_update;
	reg [31:8] rdata_q;
	reg [1:0] rdata_offset_q;
	reg [1:0] data_type_q;
	reg data_sign_ext_q;
	reg data_we_q;
	wire [1:0] data_offset;
	reg [3:0] data_be;
	reg [31:0] data_wdata;
	reg [31:0] data_rdata_ext;
	reg [31:0] rdata_w_ext;
	reg [31:0] rdata_h_ext;
	reg [31:0] rdata_b_ext;
	wire split_misaligned_access;
	reg handle_misaligned_q;
	reg handle_misaligned_d;
	reg pmp_err_q;
	reg pmp_err_d;
	reg lsu_err_q;
	reg lsu_err_d;
	wire data_or_pmp_err;
	reg [2:0] ls_fsm_cs;
	reg [2:0] ls_fsm_ns;
	assign data_addr = adder_result_ex_i;
	assign data_offset = data_addr[1:0];
	always @(*)
		case (lsu_type_i)
			2'b00:
				if (!handle_misaligned_q)
					case (data_offset)
						2'b00: data_be = 4'b1111;
						2'b01: data_be = 4'b1110;
						2'b10: data_be = 4'b1100;
						2'b11: data_be = 4'b1000;
						default: data_be = 4'b1111;
					endcase
				else
					case (data_offset)
						2'b00: data_be = 4'b0000;
						2'b01: data_be = 4'b0001;
						2'b10: data_be = 4'b0011;
						2'b11: data_be = 4'b0111;
						default: data_be = 4'b1111;
					endcase
			2'b01:
				if (!handle_misaligned_q)
					case (data_offset)
						2'b00: data_be = 4'b0011;
						2'b01: data_be = 4'b0110;
						2'b10: data_be = 4'b1100;
						2'b11: data_be = 4'b1000;
						default: data_be = 4'b1111;
					endcase
				else
					data_be = 4'b0001;
			2'b10, 2'b11:
				case (data_offset)
					2'b00: data_be = 4'b0001;
					2'b01: data_be = 4'b0010;
					2'b10: data_be = 4'b0100;
					2'b11: data_be = 4'b1000;
					default: data_be = 4'b1111;
				endcase
			default: data_be = 4'b1111;
		endcase
	always @(*)
		case (data_offset)
			2'b00: data_wdata = lsu_wdata_i[31:0];
			2'b01: data_wdata = {lsu_wdata_i[23:0], lsu_wdata_i[31:24]};
			2'b10: data_wdata = {lsu_wdata_i[15:0], lsu_wdata_i[31:16]};
			2'b11: data_wdata = {lsu_wdata_i[7:0], lsu_wdata_i[31:8]};
			default: data_wdata = lsu_wdata_i[31:0];
		endcase
	always @(posedge clk_i or negedge rst_ni)
		if (!rst_ni)
			rdata_q <= {24 {1'sb0}};
		else if (rdata_update)
			rdata_q <= data_rdata_i[31:8];
	always @(posedge clk_i or negedge rst_ni)
		if (!rst_ni) begin
			rdata_offset_q <= 2'h0;
			data_type_q <= 2'h0;
			data_sign_ext_q <= 1'b0;
			data_we_q <= 1'b0;
		end
		else if (ctrl_update) begin
			rdata_offset_q <= data_offset;
			data_type_q <= lsu_type_i;
			data_sign_ext_q <= lsu_sign_ext_i;
			data_we_q <= lsu_we_i;
		end
	always @(posedge clk_i or negedge rst_ni)
		if (!rst_ni)
			addr_last_q <= {32 {1'sb0}};
		else if (addr_update)
			addr_last_q <= data_addr;
	always @(*)
		case (rdata_offset_q)
			2'b00: rdata_w_ext = data_rdata_i[31:0];
			2'b01: rdata_w_ext = {data_rdata_i[7:0], rdata_q[31:8]};
			2'b10: rdata_w_ext = {data_rdata_i[15:0], rdata_q[31:16]};
			2'b11: rdata_w_ext = {data_rdata_i[23:0], rdata_q[31:24]};
			default: rdata_w_ext = data_rdata_i[31:0];
		endcase
	always @(*)
		case (rdata_offset_q)
			2'b00:
				if (!data_sign_ext_q)
					rdata_h_ext = {16'h0000, data_rdata_i[15:0]};
				else
					rdata_h_ext = {{16 {data_rdata_i[15]}}, data_rdata_i[15:0]};
			2'b01:
				if (!data_sign_ext_q)
					rdata_h_ext = {16'h0000, data_rdata_i[23:8]};
				else
					rdata_h_ext = {{16 {data_rdata_i[23]}}, data_rdata_i[23:8]};
			2'b10:
				if (!data_sign_ext_q)
					rdata_h_ext = {16'h0000, data_rdata_i[31:16]};
				else
					rdata_h_ext = {{16 {data_rdata_i[31]}}, data_rdata_i[31:16]};
			2'b11:
				if (!data_sign_ext_q)
					rdata_h_ext = {16'h0000, data_rdata_i[7:0], rdata_q[31:24]};
				else
					rdata_h_ext = {{16 {data_rdata_i[7]}}, data_rdata_i[7:0], rdata_q[31:24]};
			default: rdata_h_ext = {16'h0000, data_rdata_i[15:0]};
		endcase
	always @(*)
		case (rdata_offset_q)
			2'b00:
				if (!data_sign_ext_q)
					rdata_b_ext = {24'h000000, data_rdata_i[7:0]};
				else
					rdata_b_ext = {{24 {data_rdata_i[7]}}, data_rdata_i[7:0]};
			2'b01:
				if (!data_sign_ext_q)
					rdata_b_ext = {24'h000000, data_rdata_i[15:8]};
				else
					rdata_b_ext = {{24 {data_rdata_i[15]}}, data_rdata_i[15:8]};
			2'b10:
				if (!data_sign_ext_q)
					rdata_b_ext = {24'h000000, data_rdata_i[23:16]};
				else
					rdata_b_ext = {{24 {data_rdata_i[23]}}, data_rdata_i[23:16]};
			2'b11:
				if (!data_sign_ext_q)
					rdata_b_ext = {24'h000000, data_rdata_i[31:24]};
				else
					rdata_b_ext = {{24 {data_rdata_i[31]}}, data_rdata_i[31:24]};
			default: rdata_b_ext = {24'h000000, data_rdata_i[7:0]};
		endcase
	always @(*)
		case (data_type_q)
			2'b00: data_rdata_ext = rdata_w_ext;
			2'b01: data_rdata_ext = rdata_h_ext;
			2'b10, 2'b11: data_rdata_ext = rdata_b_ext;
			default: data_rdata_ext = rdata_w_ext;
		endcase
	assign split_misaligned_access = ((lsu_type_i == 2'b00) && (data_offset != 2'b00)) || ((lsu_type_i == 2'b01) && (data_offset == 2'b11));
	localparam [2:0] IDLE = 0;
	localparam [2:0] WAIT_GNT = 3;
	localparam [2:0] WAIT_GNT_MIS = 1;
	localparam [2:0] WAIT_RVALID_MIS = 2;
	localparam [2:0] WAIT_RVALID_MIS_GNTS_DONE = 4;
	always @(*) begin
		ls_fsm_ns = ls_fsm_cs;
		data_req_o = 1'b0;
		addr_incr_req_o = 1'b0;
		handle_misaligned_d = handle_misaligned_q;
		pmp_err_d = pmp_err_q;
		lsu_err_d = lsu_err_q;
		addr_update = 1'b0;
		ctrl_update = 1'b0;
		rdata_update = 1'b0;
		perf_load_o = 1'b0;
		perf_store_o = 1'b0;
		case (ls_fsm_cs)
			IDLE: begin
				pmp_err_d = 1'b0;
				if (lsu_req_i) begin
					data_req_o = 1'b1;
					pmp_err_d = data_pmp_err_i;
					lsu_err_d = 1'b0;
					perf_load_o = ~lsu_we_i;
					perf_store_o = lsu_we_i;
					if (data_gnt_i) begin
						ctrl_update = 1'b1;
						addr_update = 1'b1;
						handle_misaligned_d = split_misaligned_access;
						ls_fsm_ns = (split_misaligned_access ? WAIT_RVALID_MIS : IDLE);
					end
					else
						ls_fsm_ns = (split_misaligned_access ? WAIT_GNT_MIS : WAIT_GNT);
				end
			end
			WAIT_GNT_MIS: begin
				data_req_o = 1'b1;
				if (data_gnt_i || pmp_err_q) begin
					addr_update = 1'b1;
					ctrl_update = 1'b1;
					handle_misaligned_d = 1'b1;
					ls_fsm_ns = WAIT_RVALID_MIS;
				end
			end
			WAIT_RVALID_MIS: begin
				data_req_o = 1'b1;
				addr_incr_req_o = 1'b1;
				if (data_rvalid_i || pmp_err_q) begin
					pmp_err_d = data_pmp_err_i;
					lsu_err_d = data_err_i | pmp_err_q;
					rdata_update = ~data_we_q;
					ls_fsm_ns = (data_gnt_i ? IDLE : WAIT_GNT);
					addr_update = data_gnt_i & ~(data_err_i | pmp_err_q);
					handle_misaligned_d = ~data_gnt_i;
				end
				else if (data_gnt_i) begin
					ls_fsm_ns = WAIT_RVALID_MIS_GNTS_DONE;
					handle_misaligned_d = 1'b0;
				end
			end
			WAIT_GNT: begin
				addr_incr_req_o = handle_misaligned_q;
				data_req_o = 1'b1;
				if (data_gnt_i || pmp_err_q) begin
					ctrl_update = 1'b1;
					addr_update = ~lsu_err_q;
					ls_fsm_ns = IDLE;
					handle_misaligned_d = 1'b0;
				end
			end
			WAIT_RVALID_MIS_GNTS_DONE: begin
				addr_incr_req_o = 1'b1;
				if (data_rvalid_i) begin
					pmp_err_d = data_pmp_err_i;
					lsu_err_d = data_err_i;
					addr_update = ~data_err_i;
					rdata_update = ~data_we_q;
					ls_fsm_ns = IDLE;
				end
			end
			default: ls_fsm_ns = IDLE;
		endcase
	end
	assign lsu_req_done_o = (lsu_req_i | (ls_fsm_cs != IDLE)) & (ls_fsm_ns == IDLE);
	always @(posedge clk_i or negedge rst_ni)
		if (!rst_ni) begin
			ls_fsm_cs <= IDLE;
			handle_misaligned_q <= 1'sb0;
			pmp_err_q <= 1'sb0;
			lsu_err_q <= 1'sb0;
		end
		else begin
			ls_fsm_cs <= ls_fsm_ns;
			handle_misaligned_q <= handle_misaligned_d;
			pmp_err_q <= pmp_err_d;
			lsu_err_q <= lsu_err_d;
		end
	assign data_or_pmp_err = (lsu_err_q | data_err_i) | pmp_err_q;
	assign lsu_resp_valid_o = (data_rvalid_i | pmp_err_q) & (ls_fsm_cs == IDLE);
	assign lsu_rdata_valid_o = (((ls_fsm_cs == IDLE) & data_rvalid_i) & ~data_or_pmp_err) & ~data_we_q;
	assign lsu_rdata_o = data_rdata_ext;
	assign data_addr_w_aligned = {data_addr[31:2], 2'b00};
	assign data_addr_o = data_addr_w_aligned;
	assign data_wdata_o = data_wdata;
	assign data_we_o = lsu_we_i;
	assign data_be_o = data_be;
	assign addr_last_o = addr_last_q;
	assign load_err_o = (data_or_pmp_err & ~data_we_q) & lsu_resp_valid_o;
	assign store_err_o = (data_or_pmp_err & data_we_q) & lsu_resp_valid_o;
	assign busy_o = ls_fsm_cs != IDLE;
endmodule