diff --git a/Makefile b/Makefile index 40022dd..77bb182 100644 --- a/Makefile +++ b/Makefile @@ -16,7 +16,6 @@ FIRMWARE_OBJS = firmware/start.o firmware/irq.o firmware/print.o firmware/hello. GCC_WARNS = -Werror -Wall -Wextra -Wshadow -Wundef -Wpointer-arith -Wcast-qual -Wcast-align -Wwrite-strings GCC_WARNS += -Wredundant-decls -Wstrict-prototypes -Wmissing-prototypes -pedantic # -Wconversion TOOLCHAIN_PREFIX = $(RISCV_GNU_TOOLCHAIN_INSTALL_PREFIX)/bin/riscv32-unknown-elf- -COMPRESSED_ISA = C # Add things like "export http_proxy=... https_proxy=..." here GIT_ENV = true @@ -30,13 +29,9 @@ test_wb_vcd: testbench_wb.vvp firmware/firmware.hex test_verilator: testbench_verilator firmware/firmware.hex ./testbench_verilator -testbench_wb.vvp: testbench_wb.v picorv32.v - $(IVERILOG) -o $@ $(subst C,-DCOMPRESSED_ISA,$(COMPRESSED_ISA)) $^ - chmod -x $@ - testbench_verilator: testbench_wb.v picorv32.v testbench.cc $(VERILATOR) --cc --exe -Wno-lint -trace --top-module picorv32_wrapper testbench_wb.v picorv32.v testbench.cc \ - $(subst C,-DCOMPRESSED_ISA,$(COMPRESSED_ISA)) --Mdir testbench_verilator_dir + --Mdir testbench_verilator_dir $(MAKE) -C testbench_verilator_dir -f Vpicorv32_wrapper.mk cp testbench_verilator_dir/Vpicorv32_wrapper testbench_verilator @@ -55,16 +50,9 @@ check.smt2: picorv32.v synth.v: picorv32.v scripts/yosys/synth_sim.ys yosys -qv3 -l synth.log scripts/yosys/synth_sim.ys -# firmware/firmware.hex: firmware/firmware.bin firmware/makehex.py -# $(PYTHON) firmware/makehex.py $< 32768 > $@ - firmware/firmware.hex: firmware/firmware.elf $(TOOLCHAIN_PREFIX)objcopy -O verilog $< $@ -# firmware/firmware.bin: firmware/firmware.elf -# $(TOOLCHAIN_PREFIX)objcopy -O binary $< $@ -# chmod -x $@ - firmware/firmware.elf: $(FIRMWARE_OBJS) $(TEST_OBJS) firmware/sections.lds $(TOOLCHAIN_PREFIX)gcc -Os -mabi=ilp32 -march=rv32im -ffreestanding -nostdlib -o $@ \ -Wl,--build-id=none,-Bstatic,-T,firmware/sections.lds,-Map,firmware/firmware.map,--strip-debug \ diff --git a/picorv32.v b/picorv32.v index 1db3a61..45a6732 100644 --- a/picorv32.v +++ b/picorv32.v @@ -60,7 +60,6 @@ module picorv32 #( parameter [ 0:0] BARREL_SHIFTER = 0, parameter [ 0:0] TWO_CYCLE_COMPARE = 0, parameter [ 0:0] TWO_CYCLE_ALU = 0, - parameter [ 0:0] COMPRESSED_ISA = 0, parameter [ 0:0] CATCH_MISALIGN = 1, parameter [ 0:0] CATCH_ILLINSN = 1, parameter [ 0:0] ENABLE_PCPI = 0, @@ -280,42 +279,31 @@ module picorv32 #( reg mem_do_wdata; wire mem_xfer; - reg mem_la_secondword, mem_la_firstword_reg, last_mem_valid; - wire mem_la_firstword = COMPRESSED_ISA && (mem_do_prefetch || mem_do_rinst) && next_pc[1] && !mem_la_secondword; - wire mem_la_firstword_xfer = COMPRESSED_ISA && mem_xfer && (!last_mem_valid ? mem_la_firstword : mem_la_firstword_reg); + reg last_mem_valid; - reg prefetched_high_word; - reg clear_prefetched_high_word; reg [15:0] mem_16bit_buffer; wire [31:0] mem_rdata_latched_noshuffle; wire [31:0] mem_rdata_latched; - wire mem_la_use_prefetched_high_word = COMPRESSED_ISA && mem_la_firstword && prefetched_high_word && !clear_prefetched_high_word; - assign mem_xfer = (mem_valid && mem_ready) || (mem_la_use_prefetched_high_word && mem_do_rinst); + assign mem_xfer = mem_valid && mem_ready; wire mem_busy = |{mem_do_prefetch, mem_do_rinst, mem_do_rdata, mem_do_wdata}; - wire mem_done = resetn && ((mem_xfer && |mem_state && (mem_do_rinst || mem_do_rdata || mem_do_wdata)) || (&mem_state && mem_do_rinst)) && - (!mem_la_firstword || (~&mem_rdata_latched[1:0] && mem_xfer)); + wire mem_done = resetn && ((mem_xfer && |mem_state && (mem_do_rinst || mem_do_rdata || mem_do_wdata)) || (&mem_state && mem_do_rinst)); assign mem_la_write = resetn && !mem_state && mem_do_wdata; - assign mem_la_read = resetn && ((!mem_la_use_prefetched_high_word && !mem_state && (mem_do_rinst || mem_do_prefetch || mem_do_rdata)) || - (COMPRESSED_ISA && mem_xfer && (!last_mem_valid ? mem_la_firstword : mem_la_firstword_reg) && !mem_la_secondword && &mem_rdata_latched[1:0])); - assign mem_la_addr = (mem_do_prefetch || mem_do_rinst) ? {next_pc[31:2] + mem_la_firstword_xfer, 2'b00} : {reg_op1[31:2], 2'b00}; + assign mem_la_read = resetn && ((!mem_state && (mem_do_rinst || mem_do_prefetch || mem_do_rdata))); + assign mem_la_addr = (mem_do_prefetch || mem_do_rinst) ? {next_pc[31:2], 2'b00} : {reg_op1[31:2], 2'b00}; assign mem_rdata_latched_noshuffle = (mem_xfer || LATCHED_MEM_RDATA) ? mem_rdata : mem_rdata_q; - assign mem_rdata_latched = COMPRESSED_ISA && mem_la_use_prefetched_high_word ? {16'bx, mem_16bit_buffer} : - COMPRESSED_ISA && mem_la_secondword ? {mem_rdata_latched_noshuffle[15:0], mem_16bit_buffer} : - COMPRESSED_ISA && mem_la_firstword ? {16'bx, mem_rdata_latched_noshuffle[31:16]} : mem_rdata_latched_noshuffle; + assign mem_rdata_latched = mem_rdata_latched_noshuffle; always @(posedge clk) begin if (!resetn) begin - mem_la_firstword_reg <= 0; last_mem_valid <= 0; end else begin if (!last_mem_valid) - mem_la_firstword_reg <= mem_la_firstword; last_mem_valid <= mem_valid && !mem_ready; end end @@ -351,117 +339,8 @@ module picorv32 #( always @(posedge clk) begin if (mem_xfer) begin - mem_rdata_q <= COMPRESSED_ISA ? mem_rdata_latched : mem_rdata; - next_insn_opcode <= COMPRESSED_ISA ? mem_rdata_latched : mem_rdata; - end - - if (COMPRESSED_ISA && mem_done && (mem_do_prefetch || mem_do_rinst)) begin - case (mem_rdata_latched[1:0]) - 2'b00: begin // Quadrant 0 - case (mem_rdata_latched[15:13]) - 3'b000: begin // C.ADDI4SPN - mem_rdata_q[14:12] <= 3'b000; - mem_rdata_q[31:20] <= {2'b0, mem_rdata_latched[10:7], mem_rdata_latched[12:11], mem_rdata_latched[5], mem_rdata_latched[6], 2'b00}; - end - 3'b010: begin // C.LW - mem_rdata_q[31:20] <= {5'b0, mem_rdata_latched[5], mem_rdata_latched[12:10], mem_rdata_latched[6], 2'b00}; - mem_rdata_q[14:12] <= 3'b 010; - end - 3'b 110: begin // C.SW - {mem_rdata_q[31:25], mem_rdata_q[11:7]} <= {5'b0, mem_rdata_latched[5], mem_rdata_latched[12:10], mem_rdata_latched[6], 2'b00}; - mem_rdata_q[14:12] <= 3'b 010; - end - endcase - end - 2'b01: begin // Quadrant 1 - case (mem_rdata_latched[15:13]) - 3'b 000: begin // C.ADDI - mem_rdata_q[14:12] <= 3'b000; - mem_rdata_q[31:20] <= $signed({mem_rdata_latched[12], mem_rdata_latched[6:2]}); - end - 3'b 010: begin // C.LI - mem_rdata_q[14:12] <= 3'b000; - mem_rdata_q[31:20] <= $signed({mem_rdata_latched[12], mem_rdata_latched[6:2]}); - end - 3'b 011: begin - if (mem_rdata_latched[11:7] == 2) begin // C.ADDI16SP - mem_rdata_q[14:12] <= 3'b000; - mem_rdata_q[31:20] <= $signed({mem_rdata_latched[12], mem_rdata_latched[4:3], - mem_rdata_latched[5], mem_rdata_latched[2], mem_rdata_latched[6], 4'b 0000}); - end else begin // C.LUI - mem_rdata_q[31:12] <= $signed({mem_rdata_latched[12], mem_rdata_latched[6:2]}); - end - end - 3'b100: begin - if (mem_rdata_latched[11:10] == 2'b00) begin // C.SRLI - mem_rdata_q[31:25] <= 7'b0000000; - mem_rdata_q[14:12] <= 3'b 101; - end - if (mem_rdata_latched[11:10] == 2'b01) begin // C.SRAI - mem_rdata_q[31:25] <= 7'b0100000; - mem_rdata_q[14:12] <= 3'b 101; - end - if (mem_rdata_latched[11:10] == 2'b10) begin // C.ANDI - mem_rdata_q[14:12] <= 3'b111; - mem_rdata_q[31:20] <= $signed({mem_rdata_latched[12], mem_rdata_latched[6:2]}); - end - if (mem_rdata_latched[12:10] == 3'b011) begin // C.SUB, C.XOR, C.OR, C.AND - if (mem_rdata_latched[6:5] == 2'b00) mem_rdata_q[14:12] <= 3'b000; - if (mem_rdata_latched[6:5] == 2'b01) mem_rdata_q[14:12] <= 3'b100; - if (mem_rdata_latched[6:5] == 2'b10) mem_rdata_q[14:12] <= 3'b110; - if (mem_rdata_latched[6:5] == 2'b11) mem_rdata_q[14:12] <= 3'b111; - mem_rdata_q[31:25] <= mem_rdata_latched[6:5] == 2'b00 ? 7'b0100000 : 7'b0000000; - end - end - 3'b 110: begin // C.BEQZ - mem_rdata_q[14:12] <= 3'b000; - { mem_rdata_q[31], mem_rdata_q[7], mem_rdata_q[30:25], mem_rdata_q[11:8] } <= - $signed({mem_rdata_latched[12], mem_rdata_latched[6:5], mem_rdata_latched[2], - mem_rdata_latched[11:10], mem_rdata_latched[4:3]}); - end - 3'b 111: begin // C.BNEZ - mem_rdata_q[14:12] <= 3'b001; - { mem_rdata_q[31], mem_rdata_q[7], mem_rdata_q[30:25], mem_rdata_q[11:8] } <= - $signed({mem_rdata_latched[12], mem_rdata_latched[6:5], mem_rdata_latched[2], - mem_rdata_latched[11:10], mem_rdata_latched[4:3]}); - end - endcase - end - 2'b10: begin // Quadrant 2 - case (mem_rdata_latched[15:13]) - 3'b000: begin // C.SLLI - mem_rdata_q[31:25] <= 7'b0000000; - mem_rdata_q[14:12] <= 3'b 001; - end - 3'b010: begin // C.LWSP - mem_rdata_q[31:20] <= {4'b0, mem_rdata_latched[3:2], mem_rdata_latched[12], mem_rdata_latched[6:4], 2'b00}; - mem_rdata_q[14:12] <= 3'b 010; - end - 3'b100: begin - if (mem_rdata_latched[12] == 0 && mem_rdata_latched[6:2] == 0) begin // C.JR - mem_rdata_q[14:12] <= 3'b000; - mem_rdata_q[31:20] <= 12'b0; - end - if (mem_rdata_latched[12] == 0 && mem_rdata_latched[6:2] != 0) begin // C.MV - mem_rdata_q[14:12] <= 3'b000; - mem_rdata_q[31:25] <= 7'b0000000; - end - if (mem_rdata_latched[12] != 0 && mem_rdata_latched[11:7] != 0 && mem_rdata_latched[6:2] == 0) begin // C.JALR - mem_rdata_q[14:12] <= 3'b000; - mem_rdata_q[31:20] <= 12'b0; - end - if (mem_rdata_latched[12] != 0 && mem_rdata_latched[6:2] != 0) begin // C.ADD - mem_rdata_q[14:12] <= 3'b000; - mem_rdata_q[31:25] <= 7'b0000000; - end - end - 3'b110: begin // C.SWSP - {mem_rdata_q[31:25], mem_rdata_q[11:7]} <= {4'b0, mem_rdata_latched[8:7], mem_rdata_latched[12:9], 2'b00}; - mem_rdata_q[14:12] <= 3'b 010; - end - endcase - end - endcase + mem_rdata_q <= mem_rdata; + next_insn_opcode <= mem_rdata; end end @@ -490,8 +369,6 @@ module picorv32 #( mem_state <= 0; if (!resetn || mem_ready) mem_valid <= 0; - mem_la_secondword <= 0; - prefetched_high_word <= 0; end else begin if (mem_la_read || mem_la_write) begin mem_addr <= mem_la_addr; @@ -503,7 +380,7 @@ module picorv32 #( case (mem_state) 0: begin if (mem_do_prefetch || mem_do_rinst || mem_do_rdata) begin - mem_valid <= !mem_la_use_prefetched_high_word; + mem_valid <= 1; mem_instr <= mem_do_prefetch || mem_do_rinst; mem_wstrb <= 0; mem_state <= 1; @@ -517,27 +394,11 @@ module picorv32 #( 1: begin `assert(mem_wstrb == 0); `assert(mem_do_prefetch || mem_do_rinst || mem_do_rdata); - `assert(mem_valid == !mem_la_use_prefetched_high_word); + `assert(mem_valid == 1); `assert(mem_instr == (mem_do_prefetch || mem_do_rinst)); if (mem_xfer) begin - if (COMPRESSED_ISA && mem_la_read) begin - mem_valid <= 1; - mem_la_secondword <= 1; - if (!mem_la_use_prefetched_high_word) - mem_16bit_buffer <= mem_rdata[31:16]; - end else begin - mem_valid <= 0; - mem_la_secondword <= 0; - if (COMPRESSED_ISA && !mem_do_rdata) begin - if (~&mem_rdata[1:0] || mem_la_secondword) begin - mem_16bit_buffer <= mem_rdata[31:16]; - prefetched_high_word <= 1; - end else begin - prefetched_high_word <= 0; - end - end - mem_state <= mem_do_rinst || mem_do_rdata ? 0 : 3; - end + mem_valid <= 0; + mem_state <= mem_do_rinst || mem_do_rdata ? 0 : 3; end end 2: begin @@ -557,9 +418,6 @@ module picorv32 #( end endcase end - - if (clear_prefetched_high_word) - prefetched_high_word <= 0; end @@ -812,148 +670,6 @@ module picorv32 #( decoded_rs1 <= ENABLE_IRQ_QREGS ? irqregs_offset : 3; // instr_retirq compressed_instr <= 0; - if (COMPRESSED_ISA && mem_rdata_latched[1:0] != 2'b11) begin - compressed_instr <= 1; - decoded_rd <= 0; - decoded_rs1 <= 0; - decoded_rs2 <= 0; - - { decoded_imm_j[31:11], decoded_imm_j[4], decoded_imm_j[9:8], decoded_imm_j[10], decoded_imm_j[6], - decoded_imm_j[7], decoded_imm_j[3:1], decoded_imm_j[5], decoded_imm_j[0] } <= $signed({mem_rdata_latched[12:2], 1'b0}); - - case (mem_rdata_latched[1:0]) - 2'b00: begin // Quadrant 0 - case (mem_rdata_latched[15:13]) - 3'b000: begin // C.ADDI4SPN - is_alu_reg_imm <= |mem_rdata_latched[12:5]; - decoded_rs1 <= 2; - decoded_rd <= 8 + mem_rdata_latched[4:2]; - end - 3'b010: begin // C.LW - is_lb_lh_lw_lbu_lhu <= 1; - decoded_rs1 <= 8 + mem_rdata_latched[9:7]; - decoded_rd <= 8 + mem_rdata_latched[4:2]; - end - 3'b110: begin // C.SW - is_sb_sh_sw <= 1; - decoded_rs1 <= 8 + mem_rdata_latched[9:7]; - decoded_rs2 <= 8 + mem_rdata_latched[4:2]; - end - endcase - end - 2'b01: begin // Quadrant 1 - case (mem_rdata_latched[15:13]) - 3'b000: begin // C.NOP / C.ADDI - is_alu_reg_imm <= 1; - decoded_rd <= mem_rdata_latched[11:7]; - decoded_rs1 <= mem_rdata_latched[11:7]; - end - 3'b001: begin // C.JAL - instr_jal <= 1; - decoded_rd <= 1; - end - 3'b 010: begin // C.LI - is_alu_reg_imm <= 1; - decoded_rd <= mem_rdata_latched[11:7]; - decoded_rs1 <= 0; - end - 3'b 011: begin - if (mem_rdata_latched[12] || mem_rdata_latched[6:2]) begin - if (mem_rdata_latched[11:7] == 2) begin // C.ADDI16SP - is_alu_reg_imm <= 1; - decoded_rd <= mem_rdata_latched[11:7]; - decoded_rs1 <= mem_rdata_latched[11:7]; - end else begin // C.LUI - instr_lui <= 1; - decoded_rd <= mem_rdata_latched[11:7]; - decoded_rs1 <= 0; - end - end - end - 3'b100: begin - if (!mem_rdata_latched[11] && !mem_rdata_latched[12]) begin // C.SRLI, C.SRAI - is_alu_reg_imm <= 1; - decoded_rd <= 8 + mem_rdata_latched[9:7]; - decoded_rs1 <= 8 + mem_rdata_latched[9:7]; - decoded_rs2 <= {mem_rdata_latched[12], mem_rdata_latched[6:2]}; - end - if (mem_rdata_latched[11:10] == 2'b10) begin // C.ANDI - is_alu_reg_imm <= 1; - decoded_rd <= 8 + mem_rdata_latched[9:7]; - decoded_rs1 <= 8 + mem_rdata_latched[9:7]; - end - if (mem_rdata_latched[12:10] == 3'b011) begin // C.SUB, C.XOR, C.OR, C.AND - is_alu_reg_reg <= 1; - decoded_rd <= 8 + mem_rdata_latched[9:7]; - decoded_rs1 <= 8 + mem_rdata_latched[9:7]; - decoded_rs2 <= 8 + mem_rdata_latched[4:2]; - end - end - 3'b101: begin // C.J - instr_jal <= 1; - end - 3'b110: begin // C.BEQZ - is_beq_bne_blt_bge_bltu_bgeu <= 1; - decoded_rs1 <= 8 + mem_rdata_latched[9:7]; - decoded_rs2 <= 0; - end - 3'b111: begin // C.BNEZ - is_beq_bne_blt_bge_bltu_bgeu <= 1; - decoded_rs1 <= 8 + mem_rdata_latched[9:7]; - decoded_rs2 <= 0; - end - endcase - end - 2'b10: begin // Quadrant 2 - case (mem_rdata_latched[15:13]) - 3'b000: begin // C.SLLI - if (!mem_rdata_latched[12]) begin - is_alu_reg_imm <= 1; - decoded_rd <= mem_rdata_latched[11:7]; - decoded_rs1 <= mem_rdata_latched[11:7]; - decoded_rs2 <= {mem_rdata_latched[12], mem_rdata_latched[6:2]}; - end - end - 3'b010: begin // C.LWSP - if (mem_rdata_latched[11:7]) begin - is_lb_lh_lw_lbu_lhu <= 1; - decoded_rd <= mem_rdata_latched[11:7]; - decoded_rs1 <= 2; - end - end - 3'b100: begin - if (mem_rdata_latched[12] == 0 && mem_rdata_latched[11:7] != 0 && mem_rdata_latched[6:2] == 0) begin // C.JR - instr_jalr <= 1; - decoded_rd <= 0; - decoded_rs1 <= mem_rdata_latched[11:7]; - end - if (mem_rdata_latched[12] == 0 && mem_rdata_latched[6:2] != 0) begin // C.MV - is_alu_reg_reg <= 1; - decoded_rd <= mem_rdata_latched[11:7]; - decoded_rs1 <= 0; - decoded_rs2 <= mem_rdata_latched[6:2]; - end - if (mem_rdata_latched[12] != 0 && mem_rdata_latched[11:7] != 0 && mem_rdata_latched[6:2] == 0) begin // C.JALR - instr_jalr <= 1; - decoded_rd <= 1; - decoded_rs1 <= mem_rdata_latched[11:7]; - end - if (mem_rdata_latched[12] != 0 && mem_rdata_latched[6:2] != 0) begin // C.ADD - is_alu_reg_reg <= 1; - decoded_rd <= mem_rdata_latched[11:7]; - decoded_rs1 <= mem_rdata_latched[11:7]; - decoded_rs2 <= mem_rdata_latched[6:2]; - end - end - 3'b110: begin // C.SWSP - is_sb_sh_sw <= 1; - decoded_rs1 <= 2; - decoded_rs2 <= mem_rdata_latched[6:2]; - end - endcase - end - endcase - end end if (decoder_trigger && !decoder_pseudo_trigger) begin @@ -1005,8 +721,7 @@ module picorv32 #( instr_rdinstr <= (mem_rdata_q[6:0] == 7'b1110011 && mem_rdata_q[31:12] == 'b11000000001000000010); instr_rdinstrh <= (mem_rdata_q[6:0] == 7'b1110011 && mem_rdata_q[31:12] == 'b11001000001000000010); - instr_ecall_ebreak <= ((mem_rdata_q[6:0] == 7'b1110011 && !mem_rdata_q[31:21] && !mem_rdata_q[19:7]) || - (COMPRESSED_ISA && mem_rdata_q[15:0] == 16'h9002)); + instr_ecall_ebreak <= (mem_rdata_q[6:0] == 7'b1110011 && !mem_rdata_q[31:21] && !mem_rdata_q[19:7]); instr_getq <= mem_rdata_q[6:0] == 7'b0001011 && mem_rdata_q[31:25] == 7'b0000000 && ENABLE_IRQ && ENABLE_IRQ_QREGS; instr_setq <= mem_rdata_q[6:0] == 7'b0001011 && mem_rdata_q[31:25] == 7'b0000001 && ENABLE_IRQ && ENABLE_IRQ_QREGS; @@ -1206,17 +921,6 @@ module picorv32 #( `endif end - reg clear_prefetched_high_word_q; - always @(posedge clk) clear_prefetched_high_word_q <= clear_prefetched_high_word; - - always @* begin - clear_prefetched_high_word = clear_prefetched_high_word_q; - if (!prefetched_high_word) - clear_prefetched_high_word = 0; - if (latched_branch || irq_state || !resetn) - clear_prefetched_high_word = COMPRESSED_ISA; - end - reg cpuregs_write; reg [31:0] cpuregs_wrdata; reg [31:0] cpuregs_rs1; @@ -1840,7 +1544,7 @@ module picorv32 #( cpu_state <= cpu_state_trap; end end - if (CATCH_MISALIGN && resetn && mem_do_rinst && (COMPRESSED_ISA ? reg_pc[0] : |reg_pc[1:0])) begin + if (CATCH_MISALIGN && resetn && mem_do_rinst && (|reg_pc[1:0])) begin `debug($display("MISALIGNED INSTRUCTION: 0x%08x", reg_pc);) if (ENABLE_IRQ && !irq_mask[irq_buserror] && !irq_active) begin next_irq_pending[irq_buserror] = 1; @@ -1868,13 +1572,8 @@ module picorv32 #( irq_pending <= next_irq_pending & ~MASKED_IRQ; if (!CATCH_MISALIGN) begin - if (COMPRESSED_ISA) begin - reg_pc[0] <= 0; - reg_next_pc[0] <= 0; - end else begin - reg_pc[1:0] <= 0; - reg_next_pc[1:0] <= 0; - end + reg_pc[1:0] <= 0; + reg_next_pc[1:0] <= 0; end current_pc = 'bx; end