+ next_lsm_state = `LSM_MEMIO;
+ if (flush) begin
+ outstall = 1'b0;
+ next_lsm_state = `LSM_SETUP;
+ end
+ $display("LDMSTM: Round 1: base register: %08x, reg list %b", op0, op1[15:0]);
+ end
+ `LSM_MEMIO: begin
+ outstall = 1'b1;
+ if(next_regs == 16'b0 && !rw_wait) begin
+ next_lsm_state = `LSM_BASEWB;
+ end
+
+ $display("LDMSTM: Stage 2: Writing: regs %b, next_regs %b, reg %d, wr_data %08x, addr %08x", regs, next_regs, cur_reg, st_data, busaddr);
+ end
+ `LSM_BASEWB: begin
+ outstall = 1;
+ next_lsm_state = `LSM_WBFLUSH;
+ $display("LDMSTM: Stage 3: Writing back");
+ end
+ `LSM_WBFLUSH: begin
+ outstall = 0;
+ next_lsm_state = `LSM_SETUP;
+ end
+ default: begin
+ outstall = 1'bx;
+ next_lsm_state = 4'bxxxx;
+ end
+ endcase
+ $display("LDMSTM: Decoded, bubble %d, insn %08x, lsm state %b -> %b, stall %d", inbubble, insn, lsm_state, next_lsm_state, outstall);
+ end
+ `DECODE_LDCSTC: if(!inbubble) begin
+ $display("WARNING: Unimplemented LDCSTC");
+ end
+ `DECODE_CDP: if (!inbubble) begin
+ if (cp_busy) begin
+ outstall = 1;
+ end
+ if (!cp_ack) begin
+ /* XXX undefined instruction trap */
+ $display("WARNING: Possible CDP undefined instruction");
+ end
+ end
+ `DECODE_MRCMCR: if (!inbubble) begin
+ if (cp_busy) begin
+ outstall = 1;
+ end
+ if (!cp_ack) begin
+ $display("WARNING: Possible MRCMCR undefined instruction: cp_ack %d, cp_busy %d",cp_ack, cp_busy);
+ end
+ $display("MRCMCR: ack %d, busy %d", cp_ack, cp_busy);
+ end
+ default: begin end
+ endcase
+ end
+
+ /* Coprocessor input. */
+ always @(*)
+ begin
+ cp_req = 0;
+ cp_rnw = 1'bx;
+ cp_write = 32'hxxxxxxxx;
+ casez (insn)
+ `DECODE_CDP: if(!inbubble) begin
+ cp_req = 1;
+ end
+ `DECODE_MRCMCR: if(!inbubble) begin
+ cp_req = 1;
+ cp_rnw = insn[20] /* L */;
+ if (insn[20] == 0 /* store to coprocessor */)
+ cp_write = op0;
+ end
+ endcase
+ end
+
+ /* Register output logic. */
+ always @(*)
+ begin
+ next_write_reg = write_reg;
+ next_write_num = write_num;
+ next_write_data = write_data;
+ next_outcpsr = lsm_state == 4'b0010 ? outcpsr : cpsr;
+ next_outcpsrup = cpsrup;
+
+ casez(insn)
+ `DECODE_ALU_SWP: if (!inbubble) begin
+ next_write_reg = 1'bx;
+ next_write_num = 4'bxxxx;
+ next_write_data = 32'hxxxxxxxx;
+ case(swp_state)
+ `SWP_READING:
+ next_write_reg = 1'b0;
+ `SWP_WRITING: begin
+ next_write_reg = 1'b1;
+ next_write_num = insn[15:12];
+ next_write_data = insn[22] ? {24'b0, swp_oldval[7:0]} : swp_oldval;
+ end
+ default: begin end
+ endcase
+ end
+ `DECODE_ALU_MULT: begin
+ next_write_reg = write_reg; /* XXX workaround for ISE 10.1 bug */
+ next_write_num = write_num;
+ next_write_data = write_data;
+ next_outcpsr = lsm_state == 4'b0010 ? outcpsr : cpsr;
+ next_outcpsrup = cpsrup;
+ end
+ `DECODE_ALU_HDATA_REG,
+ `DECODE_ALU_HDATA_IMM: if(!inbubble) begin
+ next_write_reg = 1'bx;
+ next_write_num = 4'bxxxx;
+ next_write_data = 32'hxxxxxxxx;
+ case(lsrh_state)
+ `LSRH_MEMIO: begin
+ next_write_num = insn[15:12];
+ next_write_data = lsrh_rddata;
+ if(insn[20]) begin
+ next_write_reg = 1'b1;
+ end
+ end
+ `LSRH_BASEWB: begin
+ next_write_reg = 1'b1;
+ next_write_num = insn[19:16];
+ next_write_data = addr;
+ end
+ `LSRH_WBFLUSH:
+ next_write_reg = 1'b0;
+ default: begin end
+ endcase
+ end
+ `DECODE_LDRSTR_UNDEFINED: begin end
+ `DECODE_LDRSTR: if(!inbubble) begin
+ next_write_reg = 1'bx;
+ next_write_num = 4'bxxxx;
+ next_write_data = 32'hxxxxxxxx;
+ case(lsr_state)
+ `LSR_MEMIO: begin
+ next_write_reg = insn[20] /* L */;
+ next_write_num = insn[15:12];
+ if(insn[20] /* L */) begin
+ next_write_data = insn[22] /* B */ ? {24'h0, align_rddata[7:0]} : align_rddata;
+ end
+ end
+ `LSR_STRB_WR:
+ next_write_reg = 1'b0;
+ `LSR_BASEWB: begin
+ next_write_reg = 1'b1;
+ next_write_num = insn[19:16];
+ next_write_data = addr;
+ end
+ `LSR_WBFLUSH:
+ next_write_reg = 1'b0;
+ default: begin end
+ endcase
+ end
+ `DECODE_LDMSTM: if(!inbubble) begin
+ next_write_reg = 1'bx;
+ next_write_num = 4'bxxxx;
+ next_write_data = 32'hxxxxxxxx;
+ case(lsm_state)
+ `LSM_SETUP:
+ next_write_reg = 1'b0;
+ `LSM_MEMIO: begin
+ if(insn[20] /* L */) begin
+ next_write_reg = !rw_wait;
+ next_write_num = cur_reg;
+ next_write_data = rd_data;
+ end else
+ next_write_reg = 1'b0;
+ end
+ `LSM_BASEWB: begin
+ 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};
+ if(cur_reg == 4'hF && insn[22]) begin
+ next_outcpsr = spsr;
+ next_outcpsrup = 1;
+ end
+ end
+ `LSM_WBFLUSH:
+ next_write_reg = 1'b0;
+ default: begin end
+ endcase
+ end
+ `DECODE_MRCMCR: if(!inbubble) begin
+ next_write_reg = 1'bx;
+ next_write_num = 4'bxxxx;
+ next_write_data = 32'hxxxxxxxx;
+ next_outcpsr = 32'hxxxxxxxx;
+ next_outcpsrup = 1'bx;
+ if (insn[20] == 1 /* load from coprocessor */)
+ if (insn[15:12] != 4'hF /* Fuck you ARM */) begin
+ next_write_reg = 1'b1;
+ next_write_num = insn[15:12];
+ next_write_data = cp_read;
+ end else begin
+ next_outcpsr = {cp_read[31:28], cpsr[27:0]};
+ next_outcpsrup = 1;
+ end
+ end
+ endcase
+ end
+
+ /* Bus/address control logic. */
+ always @(*)
+ begin
+ rd_req = 1'b0;
+ wr_req = 1'b0;
+ offset = prev_offset;
+ addr = prevaddr;
+ raddr = 32'hxxxxxxxx;
+ busaddr = 32'hxxxxxxxx;
+ data_size = 3'bxxx;
+
+ casez(insn)
+ `DECODE_ALU_SWP: if(!inbubble) begin
+ busaddr = {op0[31:2], 2'b0};
+ data_size = insn[22] ? 3'b001 : 3'b100;
+ case(swp_state)
+ `SWP_READING:
+ rd_req = 1'b1;
+ `SWP_WRITING:
+ wr_req = 1'b1;
+ default: begin end
+ endcase
+ end
+ `DECODE_ALU_MULT: begin
+ rd_req = 1'b0; /* XXX workaround for Xilinx bug */
+ wr_req = 1'b0;
+ offset = prev_offset;
+ addr = prevaddr;
+ end
+ `DECODE_ALU_HDATA_REG,
+ `DECODE_ALU_HDATA_IMM: if(!inbubble) begin
+ addr = insn[23] ? op0 + op1 : op0 - op1; /* up/down select */
+ raddr = insn[24] ? op0 : addr; /* pre/post increment */
+ busaddr = raddr;
+ /* rotate to correct position */
+ case(insn[6:5])
+ 2'b01: /* unsigned half */
+ data_size = 3'b010;
+ 2'b10: /* signed byte */
+ data_size = 3'b001;
+ 2'b11: /* signed half */
+ data_size = 3'b010;
+ default: begin
+ data_size = 3'bxxx;