diff options
Diffstat (limited to 'cpu/cpu.ml')
| -rw-r--r-- | cpu/cpu.ml | 84 |
1 files changed, 60 insertions, 24 deletions
@@ -1,17 +1,12 @@ open Netlist_gen open Alu -let zeroes n = - const (String.make n '0') - -let one n = - const "1" ++ zeroes (n-1) -let two n = - const "01" ++ zeroes (n-2) - let ser_out, set_ser_out = loop 8 let ser_in_busy, set_ser_in_busy = loop 1 +let dbg_ra, set_dbg_ra = loop 16 +let dbg_read_data, set_dbg_read_data = loop 8 + let cpu_ram ra we wa d = (* Ram chip has word size = 8 bits and address size = 16 bits 0x0000 to 0x3FFF is ROM0 @@ -40,10 +35,9 @@ let cpu_ram ra we wa d = let read_tick = eq_c 16 ra 0x4000 in let next_tick, set_next_tick = loop 8 in - let tick = reg 8 next_tick in - let tick_d = sign_extend 1 8 (get "tick") in + let tick = nadder 8 (reg 8 next_tick) (get "tick" ++ zeroes 7) in let read_data = - set_next_tick (mux read_tick (nadder_nocarry 8 tick tick_d) tick_d) ^. + set_next_tick (mux read_tick tick (zeroes 8)) ^. mux read_tick read_data tick in let write_ser = we ^& (eq_c 16 wa 0x4102) in @@ -51,7 +45,7 @@ let cpu_ram ra we wa d = set_ser_out (mux write_ser (zeroes 8) d) ^. read_data in - let read_ser = eq_c 16 ra 0x4000 in + let read_ser = eq_c 16 ra 0x4100 in let next_ser, set_next_ser = loop 8 in let ser = reg 8 next_ser in let ser_in = get "ser_in" in @@ -63,6 +57,8 @@ let cpu_ram ra we wa d = set_next_ser ser ^. mux read_ser read_data ser in + set_dbg_ra ra ^. + set_dbg_read_data read_data ^. read_data @@ -118,7 +114,7 @@ let rl, rh, i, ex, exf, pc = let ra = mux read_ilow ra pc in let ilow = reg 8 (mux read_ilow (zeroes 8) ram_read) in - let ra = mux read_ihi ra (nadder_nocarry 16 pc (one 16)) in + let ra = mux read_ihi ra (nadder 16 pc (one 16)) in let ihi = mux read_ihi (zeroes 8) ram_read in let read_ilow = save_next_read_ihi read_ilow in @@ -130,7 +126,7 @@ let rl, rh, i, ex, exf, pc = let i = save_i i in (* Execute instruction if exec is set *) - let next_pc = nadder_nocarry 16 pc (two 16) in + let next_pc = nadder 16 pc (two 16) in let exec_finished = exec in let i_i = i % (11, 15) in @@ -149,6 +145,22 @@ let rl, rh, i, ex, exf, pc = let wr = zeroes 3 in let rwd = zeroes 16 in + (* instruction : add/sub/mul/div/unsigned/or/and/xor/nor/lsl/lsr/asr *) + let instr_alu = eq_c 3 (i_i % (2, 4)) 0b000 in + let f0 = i_i ** 0 in + let f1 = i_i ** 1 in + let double_instr_alu = instr_alu ^& (not f1) ^& (i_f ** 1) ^& (ne_n 3 i_r (const "101")) in + let instr_alu = exec ^& instr_alu in + let instr_alu_2 = reg 1 (exec ^& double_instr_alu) in + + let alu_d1, alu_d2 = alu f1 f0 i_f v_ra v_rb in + let wr = mux instr_alu wr i_r in + let rwd = mux instr_alu rwd alu_d1 in + let wr = mux instr_alu_2 wr (const "101") in + let rwd = mux instr_alu_2 rwd alu_d2 in + let exec_finished = mux double_instr_alu exec_finished instr_alu_2 in + + (* instruction : se/sne/slt/slte/sleu/sleu *) let instr_sxxx = exec ^& (eq_c 4 (i_i % (1, 4)) 0b0010) in let f0 = i_i ** 0 in @@ -159,7 +171,7 @@ let rl, rh, i, ex, exf, pc = (* instruction : incri *) let instr_incri = exec ^& eq_c 5 i_i 0b00110 in let wr = mux instr_incri wr i_r in - let rwd = mux instr_incri rwd (nadder_nocarry 16 v_r (sign_extend 8 16 i_id)) in + let rwd = mux instr_incri rwd (nadder 16 v_r (sign_extend 8 16 i_id)) in (* instruction : shi *) let instr_shi = exec ^& eq_c 5 i_i 0b00111 in let wr = mux instr_shi wr i_r in @@ -167,10 +179,10 @@ let rl, rh, i, ex, exf, pc = (* instruction : j *) let instr_j = exec ^& eq_c 5 i_i 0b01000 in - let next_pc = mux instr_j next_pc (nadder_nocarry 16 pc (sign_extend 11 16 i_jd)) in + let next_pc = mux instr_j next_pc (nadder 16 pc (sign_extend 11 16 i_jd)) in (* instruction : jal *) let instr_jal = exec ^& eq_c 5 i_i 0b01001 in - let next_pc = mux instr_jal next_pc (nadder_nocarry 16 pc (sign_extend 11 16 i_jd)) in + let next_pc = mux instr_jal next_pc (nadder 16 pc (sign_extend 11 16 i_jd)) in let instr_jalxx = instr_jal in (* instruction : jr/jalr/jer/jner/jltr/jler/jltru/ljeru *) let instr_jxxr = exec ^& eq_c 4 (i_i % (1, 4)) 0b0101 in @@ -187,7 +199,7 @@ let rl, rh, i, ex, exf, pc = (* instruction : lra *) let instr_lra = exec ^& eq_c 5 i_i 0b01100 in let wr = mux instr_lra wr (const "101") in - let rwd = mux instr_lra rwd (nadder_nocarry 16 pc (sign_extend 11 16 i_jd)) in + let rwd = mux instr_lra rwd (nadder 16 pc (sign_extend 11 16 i_jd)) in (* instruction : lw/lwr/sw/swr *) let instr_lsw = eq_c 4 (i_i % (1, 4)) 0b1000 in @@ -197,8 +209,8 @@ let rl, rh, i, ex, exf, pc = let instr_lwx = instr_lswx ^& (not (i_i ** 0)) in let lswx_d = mux instr_lswr (sign_extend 5 16 i_kd) v_rb in - let lswx_addr_lo = reg 16 (nadder_nocarry 16 v_ra lswx_d) in - let lswx_addr_hi = let a, b = nadder 16 v_ra lswx_d (const "1") in b ^. reg 16 a in + let lswx_addr_lo = reg 16 (nadder 16 v_ra lswx_d) in + let lswx_addr_hi = let a, b = nadder_with_carry 16 v_ra lswx_d (const "1") in b ^. reg 16 a in let lwx_load_lo = reg 1 (exec ^& instr_lwx) in let lwx_load_hi = reg 1 lwx_load_lo in @@ -218,16 +230,38 @@ let rl, rh, i, ex, exf, pc = let we = we ^| swx_save_hi in let wa = mux swx_save_hi wa lswx_addr_hi in let d = mux swx_save_hi d (v_r % (8, 15)) in - let exec_finished = mux instr_lwx exec_finished swx_save_hi in + let exec_finished = mux instr_swx exec_finished swx_save_hi in + + (* instruction : lb/lbr/sb/sbr *) + let instr_lsb = eq_c 4 (i_i % (1, 4)) 0b1001 in + let instr_lsbr = eq_c 4 (i_i % (1, 4)) 0b1011 in + let instr_lsbx = instr_lsb ^| instr_lsbr in + let instr_sbx = instr_lsbx ^& (i_i ** 0) in + let instr_lbx = instr_lsbx ^& (not (i_i ** 0)) in + + let lsbx_d = mux instr_lsbr (sign_extend 5 16 i_kd) v_rb in + let lsbx_addr = reg 16 (nadder 16 v_ra lsbx_d) in + + let lbx_load = reg 1 (exec ^& instr_lbx) in + let ra = mux lbx_load ra lsbx_addr in + let wr = mux lbx_load wr i_r in + let rwd = mux lbx_load rwd (ram_read ++ (zeroes 8)) in + let exec_finished = mux instr_lbx exec_finished lbx_load in + + let sbx_save = reg 1 (exec ^& instr_sbx) in + let we = we ^| sbx_save in + let wa = mux sbx_save wa lsbx_addr in + let d = mux sbx_save d (v_r % (0, 7)) in + let exec_finished = mux instr_sbx exec_finished sbx_save in (* instruction : lil/lilz/liu/liuz *) let instr_lixx = eq_c 3 (i_i % (2, 4))0b110 in - let instr_lixz = i ** 0 in - let instr_liux = i ** 1 in + let instr_lixz = i_i ** 0 in + let instr_liux = i_i ** 1 in let wr = mux instr_lixx wr i_r in let rwd = mux instr_lixx rwd (mux instr_liux - ( (* lil *) i_id ++ (mux instr_lixz (v_r % (8, 15)) (zeroes 8)) ) + ( (* lil *) i_id ++ (mux instr_lixz (v_r % (8, 15)) (zeroes 8))) ( (* liu *) (mux instr_lixz (v_r % (0, 7)) (zeroes 8)) ++ i_id)) in save_cpu_regs wr rwd ^. @@ -248,6 +282,8 @@ let p = "exec_instr", 1, ex; "exec_finished", 1, exf; "instruction", 16, i; + "ra", 16, dbg_ra; + "read_data", 8, dbg_read_data; "pc", 16, pc; "r0_Z", 16, r0; "r1_A", 16, r1; |