| Line 41... |
Line 41... |
pc_source_out: out pc_source_type;
|
pc_source_out: out pc_source_type;
|
mem_source_out:out mem_source_type);
|
mem_source_out:out mem_source_type);
|
end; --entity control
|
end; --entity control
|
|
|
architecture logic of control is
|
architecture logic of control is
|
-- type alu_function_type is (alu_nothing, alu_add, alu_subtract,
|
|
-- alu_less_than, alu_less_than_signed,
|
|
-- alu_or, alu_and, alu_xor, alu_nor);
|
|
-- type shift_function_type is (
|
|
-- shift_nothing, shift_left_unsigned,
|
|
-- shift_right_signed, shift_right_unsigned);
|
|
-- type mult_function_type is (
|
|
-- mult_nothing, mult_read_lo, mult_read_hi, mult_write_lo,
|
|
-- mult_write_hi, mult_mult, mult_divide, mult_signed_divide);
|
|
-- type a_source_type is (from_reg_source, from_imm10_6);
|
|
-- type b_source_type is (from_reg_target, from_imm, from_signed_imm);
|
|
-- type c_source_type is (from_null, from_alu, from_shift,
|
|
-- from_mult, from_memory, from_pc, from_imm_shift16,
|
|
-- from_reg_source_nez, from_reg_source_eqz);
|
|
-- type pc_source_type is (from_inc4, from_inc8, from_reg_source,
|
|
-- from_opcode25_0, from_branch, from_lbranch);
|
|
begin
|
begin
|
|
|
control_proc: process(opcode, intr_signal)
|
control_proc: process(opcode, intr_signal)
|
variable op, func : std_logic_vector(5 downto 0);
|
variable op, func : std_logic_vector(5 downto 0);
|
variable rs, rt, rd : std_logic_vector(5 downto 0);
|
variable rs, rt, rd : std_logic_vector(5 downto 0);
|
| Line 74... |
Line 58... |
variable c_source : c_source_type;
|
variable c_source : c_source_type;
|
variable pc_source : pc_source_type;
|
variable pc_source : pc_source_type;
|
variable branch_function: branch_function_type;
|
variable branch_function: branch_function_type;
|
variable mem_source : mem_source_type;
|
variable mem_source : mem_source_type;
|
begin
|
begin
|
alu_function := alu_nothing;
|
alu_function := ALU_NOTHING;
|
shift_function := shift_nothing;
|
shift_function := SHIFT_NOTHING;
|
mult_function := mult_nothing;
|
mult_function := MULT_NOTHING;
|
a_source := a_from_reg_source;
|
a_source := A_FROM_REG_SOURCE;
|
b_source := b_from_reg_target;
|
b_source := B_FROM_REG_TARGET;
|
c_source := c_from_null;
|
c_source := C_FROM_NULL;
|
pc_source := from_inc4;
|
pc_source := FROM_INC4;
|
branch_function := branch_eq;
|
branch_function := BRANCH_EQ;
|
mem_source := mem_fetch;
|
mem_source := MEM_FETCH;
|
op := opcode(31 downto 26);
|
op := opcode(31 downto 26);
|
rs := '0' & opcode(25 downto 21);
|
rs := '0' & opcode(25 downto 21);
|
rt := '0' & opcode(20 downto 16);
|
rt := '0' & opcode(20 downto 16);
|
rtx := opcode(20 downto 16);
|
rtx := opcode(20 downto 16);
|
rd := '0' & opcode(15 downto 11);
|
rd := '0' & opcode(15 downto 11);
|
| Line 95... |
Line 79... |
|
|
case op is
|
case op is
|
when "000000" => --SPECIAL
|
when "000000" => --SPECIAL
|
case func is
|
case func is
|
when "000000" => --SLL r[rd]=r[rt]<<re;
|
when "000000" => --SLL r[rd]=r[rt]<<re;
|
a_source := a_from_imm10_6;
|
a_source := A_FROM_IMM10_6;
|
c_source := c_from_shift;
|
c_source := C_FROM_SHIFT;
|
shift_function := shift_left_unsigned;
|
shift_function := SHIFT_LEFT_UNSIGNED;
|
|
|
when "000010" => --SRL r[rd]=u[rt]>>re;
|
when "000010" => --SRL r[rd]=u[rt]>>re;
|
a_source := a_from_imm10_6;
|
a_source := A_FROM_IMM10_6;
|
c_source := c_from_shift;
|
c_source := C_FROM_shift;
|
shift_function := shift_right_unsigned;
|
shift_function := SHIFT_RIGHT_UNSIGNED;
|
|
|
when "000011" => --SRA r[rd]=r[rt]>>re;
|
when "000011" => --SRA r[rd]=r[rt]>>re;
|
a_source := a_from_imm10_6;
|
a_source := A_FROM_IMM10_6;
|
c_source := c_from_shift;
|
c_source := C_FROM_SHIFT;
|
shift_function := shift_right_signed;
|
shift_function := SHIFT_RIGHT_SIGNED;
|
|
|
when "000100" => --SLLV r[rd]=r[rt]<<r[rs];
|
when "000100" => --SLLV r[rd]=r[rt]<<r[rs];
|
c_source := c_from_shift;
|
c_source := C_FROM_SHIFT;
|
shift_function := shift_left_unsigned;
|
shift_function := SHIFT_LEFT_UNSIGNED;
|
|
|
when "000110" => --SRLV r[rd]=u[rt]>>r[rs];
|
when "000110" => --SRLV r[rd]=u[rt]>>r[rs];
|
c_source := c_from_shift;
|
c_source := C_FROM_SHIFT;
|
shift_function := shift_right_unsigned;
|
shift_function := SHIFT_RIGHT_UNSIGNED;
|
|
|
when "000111" => --SRAV r[rd]=r[rt]>>r[rs];
|
when "000111" => --SRAV r[rd]=r[rt]>>r[rs];
|
c_source := c_from_shift;
|
c_source := C_FROM_SHIFT;
|
shift_function := shift_right_signed;
|
shift_function := SHIFT_RIGHT_SIGNED;
|
|
|
when "001000" => --JR s->pc_next=r[rs];
|
when "001000" => --JR s->pc_next=r[rs];
|
pc_source := from_branch;
|
pc_source := FROM_BRANCH;
|
alu_function := alu_add;
|
alu_function := ALU_ADD;
|
branch_function := branch_yes;
|
branch_function := BRANCH_YES;
|
|
|
when "001001" => --JALR r[rd]=s->pc_next; s->pc_next=r[rs];
|
when "001001" => --JALR r[rd]=s->pc_next; s->pc_next=r[rs];
|
c_source := c_from_pc_plus4;
|
c_source := C_FROM_PC_PLUS4;
|
pc_source := from_branch;
|
pc_source := FROM_BRANCH;
|
alu_function := alu_add;
|
alu_function := ALU_ADD;
|
branch_function := branch_yes;
|
branch_function := BRANCH_YES;
|
|
|
when "001010" => --MOVZ if(!r[rt]) r[rd]=r[rs]; /*IV*/
|
when "001010" => --MOVZ if(!r[rt]) r[rd]=r[rs]; /*IV*/
|
-- c_source := c_from_reg_source_eqz;
|
-- c_source := C_FROM_REG_SOURCE_EQZ;
|
|
|
when "001011" => --MOVN if(r[rt]) r[rd]=r[rs]; /*IV*/
|
when "001011" => --MOVN if(r[rt]) r[rd]=r[rs]; /*IV*/
|
-- c_source := from_reg_source_nez;
|
-- c_source := FROM_REG_SOURCE_NEZ;
|
|
|
when "001100" => --SYSCALL
|
when "001100" => --SYSCALL
|
-- if(r[4]==0) printf("0x%8.8lx ",r[5]);
|
-- if(r[4]==0) printf("0x%8.8lx ",r[5]);
|
|
|
when "001101" => --BREAK s->wakeup=1;
|
when "001101" => --BREAK s->wakeup=1;
|
when "001111" => --SYNC s->wakeup=1;
|
when "001111" => --SYNC s->wakeup=1;
|
when "010000" => --MFHI r[rd]=s->hi;
|
when "010000" => --MFHI r[rd]=s->hi;
|
c_source := c_from_mult;
|
c_source := C_FROM_MULT;
|
mult_function := mult_read_hi;
|
mult_function := MULT_READ_HI;
|
|
|
when "010001" => --FTHI s->hi=r[rs];
|
when "010001" => --FTHI s->hi=r[rs];
|
mult_function := mult_write_hi;
|
mult_function := MULT_WRITE_HI;
|
|
|
when "010010" => --MFLO r[rd]=s->lo;
|
when "010010" => --MFLO r[rd]=s->lo;
|
c_source := c_from_mult;
|
c_source := C_FROM_MULT;
|
mult_function := mult_read_lo;
|
mult_function := MULT_READ_LO;
|
|
|
when "010011" => --MTLO s->lo=r[rs];
|
when "010011" => --MTLO s->lo=r[rs];
|
mult_function := mult_write_lo;
|
mult_function := MULT_WRITE_LO;
|
|
|
when "011000" => --MULT s->lo=r[rs]*r[rt]; s->hi=0;
|
when "011000" => --MULT s->lo=r[rs]*r[rt]; s->hi=0;
|
mult_function := mult_signed_mult;
|
mult_function := MULT_SIGNED_MULT;
|
|
|
when "011001" => --MULTU s->lo=r[rs]*r[rt]; s->hi=0;
|
when "011001" => --MULTU s->lo=r[rs]*r[rt]; s->hi=0;
|
mult_function := mult_mult;
|
mult_function := MULT_MULT;
|
|
|
when "011010" => --DIV s->lo=r[rs]/r[rt]; s->hi=r[rs]%r[rt];
|
when "011010" => --DIV s->lo=r[rs]/r[rt]; s->hi=r[rs]%r[rt];
|
mult_function := mult_signed_divide;
|
mult_function := MULT_SIGNED_DIVIDE;
|
|
|
when "011011" => --DIVU s->lo=r[rs]/r[rt]; s->hi=r[rs]%r[rt];
|
when "011011" => --DIVU s->lo=r[rs]/r[rt]; s->hi=r[rs]%r[rt];
|
mult_function := mult_divide;
|
mult_function := MULT_DIVIDE;
|
|
|
when "100000" => --ADD r[rd]=r[rs]+r[rt];
|
when "100000" => --ADD r[rd]=r[rs]+r[rt];
|
c_source := c_from_alu;
|
c_source := C_FROM_ALU;
|
alu_function := alu_add;
|
alu_function := ALU_ADD;
|
|
|
when "100001" => --ADDU r[rd]=r[rs]+r[rt];
|
when "100001" => --ADDU r[rd]=r[rs]+r[rt];
|
c_source := c_from_alu;
|
c_source := C_FROM_ALU;
|
alu_function := alu_add;
|
alu_function := ALU_ADD;
|
|
|
when "100010" => --SUB r[rd]=r[rs]-r[rt];
|
when "100010" => --SUB r[rd]=r[rs]-r[rt];
|
c_source := c_from_alu;
|
c_source := C_FROM_ALU;
|
alu_function := alu_subtract;
|
alu_function := ALU_SUBTRACT;
|
|
|
when "100011" => --SUBU r[rd]=r[rs]-r[rt];
|
when "100011" => --SUBU r[rd]=r[rs]-r[rt];
|
c_source := c_from_alu;
|
c_source := C_FROM_ALU;
|
alu_function := alu_subtract;
|
alu_function := ALU_SUBTRACT;
|
|
|
when "100100" => --AND r[rd]=r[rs]&r[rt];
|
when "100100" => --AND r[rd]=r[rs]&r[rt];
|
c_source := c_from_alu;
|
c_source := C_FROM_ALU;
|
alu_function := alu_and;
|
alu_function := ALU_AND;
|
|
|
when "100101" => --OR r[rd]=r[rs]|r[rt];
|
when "100101" => --OR r[rd]=r[rs]|r[rt];
|
c_source := c_from_alu;
|
c_source := C_FROM_ALU;
|
alu_function := alu_or;
|
alu_function := ALU_OR;
|
|
|
when "100110" => --XOR r[rd]=r[rs]^r[rt];
|
when "100110" => --XOR r[rd]=r[rs]^r[rt];
|
c_source := c_from_alu;
|
c_source := C_FROM_ALU;
|
alu_function := alu_xor;
|
alu_function := ALU_XOR;
|
|
|
when "100111" => --NOR r[rd]=~(r[rs]|r[rt]);
|
when "100111" => --NOR r[rd]=~(r[rs]|r[rt]);
|
c_source := c_from_alu;
|
c_source := C_FROM_ALU;
|
alu_function := alu_nor;
|
alu_function := ALU_NOR;
|
|
|
when "101010" => --SLT r[rd]=r[rs]<r[rt];
|
when "101010" => --SLT r[rd]=r[rs]<r[rt];
|
c_source := c_from_alu;
|
c_source := C_FROM_ALU;
|
alu_function := alu_less_than_signed;
|
alu_function := ALU_LESS_THAN_SIGNED;
|
|
|
when "101011" => --SLTU r[rd]=u[rs]<u[rt];
|
when "101011" => --SLTU r[rd]=u[rs]<u[rt];
|
c_source := c_from_alu;
|
c_source := C_FROM_ALU;
|
alu_function := alu_less_than;
|
alu_function := ALU_LESS_THAN;
|
|
|
when "101101" => --DADDU r[rd]=r[rs]+u[rt];
|
when "101101" => --DADDU r[rd]=r[rs]+u[rt];
|
c_source := c_from_alu;
|
c_source := C_FROM_ALU;
|
alu_function := alu_add;
|
alu_function := ALU_ADD;
|
|
|
when "110001" => --TGEU
|
when "110001" => --TGEU
|
when "110010" => --TLT
|
when "110010" => --TLT
|
when "110011" => --TLTU
|
when "110011" => --TLTU
|
when "110100" => --TEQ
|
when "110100" => --TEQ
|
when "110110" => --TNE
|
when "110110" => --TNE
|
when others =>
|
when others =>
|
end case;
|
end case;
|
|
|
when "000001" => --REGIMM
|
when "000001" => --REGIMM
|
rt := "000000";
|
rt := "000000";
|
rd := "011111";
|
rd := "011111";
|
a_source := a_from_pc;
|
a_source := A_FROM_PC;
|
b_source := b_from_immX4;
|
b_source := B_FROM_IMMX4;
|
alu_function := alu_add;
|
alu_function := ALU_ADD;
|
pc_source := from_branch;
|
pc_source := FROM_BRANCH;
|
branch_function := branch_gtz;
|
branch_function := BRANCH_GTZ;
|
--if(test) pc=pc+imm*4
|
--if(test) pc=pc+imm*4
|
|
|
case rtx is
|
case rtx is
|
when "10000" => --BLTZAL r[31]=s->pc_next; branch=r[rs]<0;
|
when "10000" => --BLTZAL r[31]=s->pc_next; branch=r[rs]<0;
|
c_source := c_from_pc_plus4;
|
c_source := C_FROM_PC_PLUS4;
|
branch_function := branch_ltz;
|
branch_function := BRANCH_LTZ;
|
|
|
when "00000" => --BLTZ branch=r[rs]<0;
|
when "00000" => --BLTZ branch=r[rs]<0;
|
branch_function := branch_ltz;
|
branch_function := BRANCH_LTZ;
|
|
|
when "10001" => --BGEZAL r[31]=s->pc_next; branch=r[rs]>=0;
|
when "10001" => --BGEZAL r[31]=s->pc_next; branch=r[rs]>=0;
|
c_source := c_from_pc_plus4;
|
c_source := C_FROM_PC_PLUS4;
|
branch_function := branch_gez;
|
branch_function := BRANCH_GEZ;
|
|
|
when "00001" => --BGEZ branch=r[rs]>=0;
|
when "00001" => --BGEZ branch=r[rs]>=0;
|
branch_function := branch_gez;
|
branch_function := BRANCH_GEZ;
|
|
|
when "10010" => --BLTZALL r[31]=s->pc_next; lbranch=r[rs]<0;
|
when "10010" => --BLTZALL r[31]=s->pc_next; lbranch=r[rs]<0;
|
c_source := c_from_pc_plus4;
|
c_source := C_FROM_PC_PLUS4;
|
pc_source := from_lbranch;
|
pc_source := FROM_LBRANCH;
|
branch_function := branch_ltz;
|
branch_function := BRANCH_LTZ;
|
|
|
when "00010" => --BLTZL lbranch=r[rs]<0;
|
when "00010" => --BLTZL lbranch=r[rs]<0;
|
pc_source := from_lbranch;
|
pc_source := FROM_LBRANCH;
|
branch_function := branch_ltz;
|
branch_function := BRANCH_LTZ;
|
|
|
when "10011" => --BGEZALL r[31]=s->pc_next; lbranch=r[rs]>=0;
|
when "10011" => --BGEZALL r[31]=s->pc_next; lbranch=r[rs]>=0;
|
c_source := c_from_pc_plus4;
|
c_source := C_FROM_PC_PLUS4;
|
pc_source := from_lbranch;
|
pc_source := FROM_LBRANCH;
|
branch_function := branch_gez;
|
branch_function := BRANCH_GEZ;
|
|
|
when "00011" => --BGEZL lbranch=r[rs]>=0;
|
when "00011" => --BGEZL lbranch=r[rs]>=0;
|
pc_source := from_lbranch;
|
pc_source := FROM_LBRANCH;
|
branch_function := branch_gez;
|
branch_function := BRANCH_GEZ;
|
|
|
when others =>
|
when others =>
|
end case;
|
end case;
|
|
|
when "000011" => --JAL r[31]=s->pc_next; s->pc_next=(s->pc&0xf0000000)|target;
|
when "000011" => --JAL r[31]=s->pc_next; s->pc_next=(s->pc&0xf0000000)|target;
|
c_source := c_from_pc_plus4;
|
c_source := C_FROM_PC_PLUS4;
|
rd := "011111";
|
rd := "011111";
|
pc_source := from_opcode25_0;
|
pc_source := FROM_OPCODE25_0;
|
|
|
when "000010" => --J s->pc_next=(s->pc&0xf0000000)|target;
|
when "000010" => --J s->pc_next=(s->pc&0xf0000000)|target;
|
pc_source := from_opcode25_0;
|
pc_source := FROM_OPCODE25_0;
|
|
|
when "000100" => --BEQ branch=r[rs]==r[rt];
|
when "000100" => --BEQ branch=r[rs]==r[rt];
|
a_source := a_from_pc;
|
a_source := A_FROM_PC;
|
b_source := b_from_immX4;
|
b_source := B_FROM_IMMX4;
|
alu_function := alu_add;
|
alu_function := ALU_ADD;
|
pc_source := from_branch;
|
pc_source := FROM_BRANCH;
|
branch_function := branch_eq;
|
branch_function := BRANCH_EQ;
|
|
|
when "000101" => --BNE branch=r[rs]!=r[rt];
|
when "000101" => --BNE branch=r[rs]!=r[rt];
|
a_source := a_from_pc;
|
a_source := A_FROM_PC;
|
b_source := b_from_immX4;
|
b_source := B_FROM_IMMX4;
|
alu_function := alu_add;
|
alu_function := ALU_ADD;
|
pc_source := from_branch;
|
pc_source := FROM_BRANCH;
|
branch_function := branch_ne;
|
branch_function := BRANCH_NE;
|
|
|
when "000110" => --BLEZ branch=r[rs]<=0;
|
when "000110" => --BLEZ branch=r[rs]<=0;
|
a_source := a_from_pc;
|
a_source := A_FROM_PC;
|
b_source := b_from_immX4;
|
b_source := b_FROM_IMMX4;
|
alu_function := alu_add;
|
alu_function := ALU_ADD;
|
pc_source := from_branch;
|
pc_source := FROM_BRANCH;
|
branch_function := branch_lez;
|
branch_function := BRANCH_LEZ;
|
|
|
when "000111" => --BGTZ branch=r[rs]>0;
|
when "000111" => --BGTZ branch=r[rs]>0;
|
a_source := a_from_pc;
|
a_source := A_FROM_PC;
|
b_source := b_from_immX4;
|
b_source := B_FROM_IMMX4;
|
alu_function := alu_add;
|
alu_function := ALU_ADD;
|
pc_source := from_branch;
|
pc_source := FROM_BRANCH;
|
branch_function := branch_gtz;
|
branch_function := BRANCH_GTZ;
|
|
|
when "001000" => --ADDI r[rt]=r[rs]+(short)imm;
|
when "001000" => --ADDI r[rt]=r[rs]+(short)imm;
|
b_source := b_from_signed_imm;
|
b_source := B_FROM_SIGNED_IMM;
|
c_source := c_from_alu;
|
c_source := C_FROM_ALU;
|
rd := rt;
|
rd := rt;
|
alu_function := alu_add;
|
alu_function := ALU_ADD;
|
|
|
when "001001" => --ADDIU u[rt]=u[rs]+(short)imm;
|
when "001001" => --ADDIU u[rt]=u[rs]+(short)imm;
|
b_source := b_from_signed_imm;
|
b_source := B_FROM_SIGNED_IMM;
|
c_source := c_from_alu;
|
c_source := C_FROM_ALU;
|
rd := rt;
|
rd := rt;
|
alu_function := alu_add;
|
alu_function := ALU_ADD;
|
|
|
when "001010" => --SLTI r[rt]=r[rs]<(short)imm;
|
when "001010" => --SLTI r[rt]=r[rs]<(short)imm;
|
b_source := b_from_signed_imm;
|
b_source := B_FROM_SIGNED_IMM;
|
c_source := c_from_alu;
|
c_source := C_FROM_ALU;
|
rd := rt;
|
rd := rt;
|
alu_function := alu_less_than_signed;
|
alu_function := ALU_LESS_THAN_SIGNED;
|
|
|
when "001011" => --SLTIU u[rt]=u[rs]<(unsigned long)(short)imm;
|
when "001011" => --SLTIU u[rt]=u[rs]<(unsigned long)(short)imm;
|
b_source := b_from_imm;
|
b_source := B_FROM_IMM;
|
c_source := c_from_alu;
|
c_source := C_FROM_ALU;
|
rd := rt;
|
rd := rt;
|
alu_function := alu_less_than;
|
alu_function := ALU_LESS_THAN;
|
|
|
when "001100" => --ANDI r[rt]=r[rs]&imm;
|
when "001100" => --ANDI r[rt]=r[rs]&imm;
|
b_source := b_from_imm;
|
b_source := B_FROM_IMM;
|
c_source := c_from_alu;
|
c_source := C_FROM_ALU;
|
rd := rt;
|
rd := rt;
|
alu_function := alu_and;
|
alu_function := ALU_AND;
|
|
|
when "001101" => --ORI r[rt]=r[rs]|imm;
|
when "001101" => --ORI r[rt]=r[rs]|imm;
|
b_source := b_from_imm;
|
b_source := B_FROM_IMM;
|
c_source := c_from_alu;
|
c_source := C_FROM_ALU;
|
rd := rt;
|
rd := rt;
|
alu_function := alu_or;
|
alu_function := ALU_OR;
|
|
|
when "001110" => --XORI r[rt]=r[rs]^imm;
|
when "001110" => --XORI r[rt]=r[rs]^imm;
|
b_source := b_from_imm;
|
b_source := B_FROM_IMM;
|
c_source := c_from_alu;
|
c_source := C_FROM_ALU;
|
rd := rt;
|
rd := rt;
|
alu_function := alu_xor;
|
alu_function := ALU_XOR;
|
|
|
when "001111" => --LUI r[rt]=(imm<<16);
|
when "001111" => --LUI r[rt]=(imm<<16);
|
c_source := c_from_imm_shift16;
|
c_source := C_FROM_IMM_SHIFT16;
|
rd := rt;
|
rd := rt;
|
|
|
when "010000" => --COP0
|
when "010000" => --COP0
|
alu_function := alu_or;
|
alu_function := ALU_OR;
|
c_source := c_from_alu;
|
c_source := C_FROM_ALU;
|
if opcode(23) = '0' then --move from CP0
|
if opcode(23) = '0' then --move from CP0
|
rs := '1' & opcode(15 downto 11);
|
rs := '1' & opcode(15 downto 11);
|
rt := "000000";
|
rt := "000000";
|
rd := '0' & opcode(20 downto 16);
|
rd := '0' & opcode(20 downto 16);
|
else --move to CP0
|
else --move to CP0
|
rs := "000000";
|
rs := "000000";
|
rd(5) := '1';
|
rd(5) := '1';
|
end if;
|
end if;
|
|
|
when "010001" => --COP1
|
when "010001" => --COP1
|
when "010010" => --COP2
|
when "010010" => --COP2
|
when "010011" => --COP3
|
when "010011" => --COP3
|
when "010100" => --BEQL lbranch=r[rs]==r[rt];
|
when "010100" => --BEQL lbranch=r[rs]==r[rt];
|
a_source := a_from_pc;
|
a_source := A_FROM_PC;
|
b_source := b_from_immX4;
|
b_source := B_FROM_IMMX4;
|
alu_function := alu_add;
|
alu_function := ALU_ADD;
|
pc_source := from_lbranch;
|
pc_source := FROM_LBRANCH;
|
branch_function := branch_eq;
|
branch_function := BRANCH_EQ;
|
|
|
when "010101" => --BNEL lbranch=r[rs]!=r[rt];
|
when "010101" => --BNEL lbranch=r[rs]!=r[rt];
|
a_source := a_from_pc;
|
a_source := A_FROM_PC;
|
b_source := b_from_immX4;
|
b_source := B_FROM_IMMX4;
|
alu_function := alu_add;
|
alu_function := ALU_ADD;
|
pc_source := from_lbranch;
|
pc_source := FROM_LBRANCH;
|
branch_function := branch_ne;
|
branch_function := BRANCH_NE;
|
|
|
when "010110" => --BLEZL lbranch=r[rs]<=0;
|
when "010110" => --BLEZL lbranch=r[rs]<=0;
|
a_source := a_from_pc;
|
a_source := A_FROM_PC;
|
b_source := b_from_immX4;
|
b_source := B_FROM_IMMX4;
|
alu_function := alu_add;
|
alu_function := ALU_ADD;
|
pc_source := from_lbranch;
|
pc_source := FROM_LBRANCH;
|
branch_function := branch_lez;
|
branch_function := BRANCH_LEZ;
|
|
|
when "010111" => --BGTZL lbranch=r[rs]>0;
|
when "010111" => --BGTZL lbranch=r[rs]>0;
|
a_source := a_from_pc;
|
a_source := A_FROM_PC;
|
b_source := b_from_immX4;
|
b_source := B_FROM_IMMX4;
|
alu_function := alu_add;
|
alu_function := ALU_ADD;
|
pc_source := from_lbranch;
|
pc_source := FROM_LBRANCH;
|
branch_function := branch_gtz;
|
branch_function := BRANCH_GTZ;
|
|
|
when "100000" => --LB r[rt]=*(signed char*)ptr;
|
when "100000" => --LB r[rt]=*(signed char*)ptr;
|
a_source := a_from_reg_source;
|
a_source := A_FROM_REG_SOURCE;
|
b_source := b_from_signed_imm;
|
b_source := B_FROM_SIGNED_IMM;
|
alu_function := alu_add;
|
alu_function := ALU_ADD;
|
rd := rt;
|
rd := rt;
|
c_source := c_from_memory;
|
c_source := C_FROM_MEMORY;
|
mem_source := mem_read8s; --address=(short)imm+r[rs];
|
mem_source := MEM_READ8S; --address=(short)imm+r[rs];
|
|
|
when "100001" => --LH r[rt]=*(signed short*)ptr;
|
when "100001" => --LH r[rt]=*(signed short*)ptr;
|
a_source := a_from_reg_source;
|
a_source := A_FROM_REG_SOURCE;
|
b_source := b_from_signed_imm;
|
b_source := B_FROM_SIGNED_IMM;
|
alu_function := alu_add;
|
alu_function := ALU_ADD;
|
rd := rt;
|
rd := rt;
|
c_source := c_from_memory;
|
c_source := C_FROM_MEMORY;
|
mem_source := mem_read16s; --address=(short)imm+r[rs];
|
mem_source := MEM_READ16S; --address=(short)imm+r[rs];
|
|
|
when "100010" => --LWL //Not Implemented
|
when "100010" => --LWL //Not Implemented
|
a_source := a_from_reg_source;
|
a_source := A_FROM_REG_SOURCE;
|
b_source := b_from_signed_imm;
|
b_source := B_FROM_SIGNED_IMM;
|
alu_function := alu_add;
|
alu_function := ALU_ADD;
|
rd := rt;
|
rd := rt;
|
c_source := c_from_memory;
|
c_source := C_FROM_MEMORY;
|
mem_source := mem_read32;
|
mem_source := MEM_READ32;
|
|
|
when "100011" => --LW r[rt]=*(long*)ptr;
|
when "100011" => --LW r[rt]=*(long*)ptr;
|
a_source := a_from_reg_source;
|
a_source := A_FROM_REG_SOURCE;
|
b_source := b_from_signed_imm;
|
b_source := B_FROM_SIGNED_IMM;
|
alu_function := alu_add;
|
alu_function := ALU_ADD;
|
rd := rt;
|
rd := rt;
|
c_source := c_from_memory;
|
c_source := C_FROM_MEMORY;
|
mem_source := mem_read32;
|
mem_source := MEM_READ32;
|
|
|
when "100100" => --LBU r[rt]=*(unsigned char*)ptr;
|
when "100100" => --LBU r[rt]=*(unsigned char*)ptr;
|
a_source := a_from_reg_source;
|
a_source := A_FROM_REG_SOURCE;
|
b_source := b_from_signed_imm;
|
b_source := B_FROM_SIGNED_IMM;
|
alu_function := alu_add;
|
alu_function := ALU_ADD;
|
rd := rt;
|
rd := rt;
|
c_source := c_from_memory;
|
c_source := C_FROM_MEMORY;
|
mem_source := mem_read8; --address=(short)imm+r[rs];
|
mem_source := MEM_READ8; --address=(short)imm+r[rs];
|
|
|
when "100101" => --LHU r[rt]=*(unsigned short*)ptr;
|
when "100101" => --LHU r[rt]=*(unsigned short*)ptr;
|
a_source := a_from_reg_source;
|
a_source := A_FROM_REG_SOURCE;
|
b_source := b_from_signed_imm;
|
b_source := B_FROM_SIGNED_IMM;
|
alu_function := alu_add;
|
alu_function := ALU_ADD;
|
rd := rt;
|
rd := rt;
|
c_source := c_from_memory;
|
c_source := C_FROM_MEMORY;
|
mem_source := mem_read16; --address=(short)imm+r[rs];
|
mem_source := MEM_READ16; --address=(short)imm+r[rs];
|
|
|
when "100110" => --LWR //Not Implemented
|
when "100110" => --LWR //Not Implemented
|
when "101000" => --SB *(char*)ptr=(char)r[rt];
|
when "101000" => --SB *(char*)ptr=(char)r[rt];
|
a_source := a_from_reg_source;
|
a_source := A_FROM_REG_SOURCE;
|
b_source := b_from_signed_imm;
|
b_source := B_FROM_SIGNED_IMM;
|
alu_function := alu_add;
|
alu_function := ALU_ADD;
|
mem_source := mem_write8; --address=(short)imm+r[rs];
|
mem_source := MEM_WRITE8; --address=(short)imm+r[rs];
|
|
|
when "101001" => --SH *(short*)ptr=(short)r[rt];
|
when "101001" => --SH *(short*)ptr=(short)r[rt];
|
a_source := a_from_reg_source;
|
a_source := A_FROM_REG_SOURCE;
|
b_source := b_from_signed_imm;
|
b_source := B_FROM_SIGNED_IMM;
|
alu_function := alu_add;
|
alu_function := ALU_ADD;
|
mem_source := mem_write16;
|
mem_source := MEM_WRITE16;
|
|
|
when "101010" => --SWL //Not Implemented
|
when "101010" => --SWL //Not Implemented
|
a_source := a_from_reg_source;
|
a_source := A_FROM_REG_SOURCE;
|
b_source := b_from_signed_imm;
|
b_source := B_FROM_SIGNED_IMM;
|
alu_function := alu_add;
|
alu_function := ALU_ADD;
|
mem_source := mem_write32; --address=(short)imm+r[rs];
|
mem_source := MEM_WRITE32; --address=(short)imm+r[rs];
|
|
|
when "101011" => --SW *(long*)ptr=r[rt];
|
when "101011" => --SW *(long*)ptr=r[rt];
|
a_source := a_from_reg_source;
|
a_source := A_FROM_REG_SOURCE;
|
b_source := b_from_signed_imm;
|
b_source := B_FROM_SIGNED_IMM;
|
alu_function := alu_add;
|
alu_function := ALU_ADD;
|
mem_source := mem_write32; --address=(short)imm+r[rs];
|
mem_source := MEM_WRITE32; --address=(short)imm+r[rs];
|
|
|
when "101110" => --SWR //Not Implemented
|
when "101110" => --SWR //Not Implemented
|
when "101111" => --CACHE
|
when "101111" => --CACHE
|
when "110000" => --LL r[rt]=*(long*)ptr;
|
when "110000" => --LL r[rt]=*(long*)ptr;
|
when "110001" => --LWC1
|
when "110001" => --LWC1
|
when "110010" => --LWC2
|
when "110010" => --LWC2
|
| Line 414... |
Line 468... |
when "111110" => --SDC2
|
when "111110" => --SDC2
|
when "111111" => --SDC3
|
when "111111" => --SDC3
|
when others =>
|
when others =>
|
end case;
|
end case;
|
|
|
if c_source = c_from_null then
|
if c_source = C_FROM_NULL then
|
rd := "000000";
|
rd := "000000";
|
end if;
|
end if;
|
|
|
if intr_signal = '1' then
|
if intr_signal = '1' then
|
rs := "111111"; --interrupt vector
|
rs := "111111"; --interrupt vector
|
rt := "000000";
|
rt := "000000";
|
rd := "101110"; --save PC in EPC
|
rd := "101110"; --save PC in EPC
|
alu_function := alu_or;
|
alu_function := ALU_OR;
|
shift_function := shift_nothing;
|
shift_function := SHIFT_NOTHING;
|
mult_function := mult_nothing;
|
mult_function := MULT_NOTHING;
|
branch_function := branch_yes;
|
branch_function := BRANCH_YES;
|
a_source := a_from_reg_source;
|
a_source := A_FROM_REG_SOURCE;
|
b_source := b_from_reg_target;
|
b_source := B_FROM_REG_TARGET;
|
c_source := c_from_pc;
|
c_source := C_FROM_pc;
|
pc_source := from_lbranch;
|
pc_source := FROM_LBRANCH;
|
mem_source := mem_fetch;
|
mem_source := MEM_FETCH;
|
end if;
|
end if;
|
|
|
rs_index <= rs;
|
rs_index <= rs;
|
rt_index <= rt;
|
rt_index <= rt;
|
rd_index <= rd;
|
rd_index <= rd;
|
