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Much refactor, so control

This commit is contained in:
Andrew Waterman 2015-01-03 13:34:38 -08:00
parent 1cb65d5ec1
commit 6181de4cc9
2 changed files with 83 additions and 67 deletions

View File

@ -14,11 +14,7 @@ class CtrlDpathIO extends Bundle
val sel_pc = UInt(OUTPUT, 3)
val killd = Bool(OUTPUT)
val ren = Vec.fill(2)(Bool(OUTPUT))
val sel_alu2 = UInt(OUTPUT, 3)
val sel_alu1 = UInt(OUTPUT, 2)
val sel_imm = UInt(OUTPUT, 3)
val fn_dw = Bool(OUTPUT)
val fn_alu = UInt(OUTPUT, SZ_ALU_FN)
val ex_ctrl = new IntCtrlSigs().asOutput
val div_mul_val = Bool(OUTPUT)
val div_mul_kill = Bool(OUTPUT)
val div_val = Bool(OUTPUT)
@ -83,6 +79,43 @@ abstract trait DecodeConstants
val table: Array[(UInt, List[UInt])]
}
class IntCtrlSigs extends Bundle {
val legal = Bool()
val fp = Bool()
val rocc = Bool()
val branch = Bool()
val jal = Bool()
val jalr = Bool()
val rrs2 = Bool()
val rrs1 = Bool()
val sel_alu2 = Bits(width = A2_X.getWidth)
val sel_alu1 = Bits(width = A1_X.getWidth)
val sel_imm = Bits(width = IMM_X.getWidth)
val alu_dw = Bool()
val alu_fn = Bits(width = FN_X.getWidth)
val mem = Bool()
val mem_cmd = Bits(width = M_SZ)
val mem_type = Bits(width = MT_SZ)
val mul = Bool()
val div = Bool()
val wrd = Bool()
val csr = Bits(width = CSR.SZ)
val fence_i = Bool()
val sret = Bool()
val scall = Bool()
val replay_next = Bool()
val fence = Bool()
val amo = Bool()
def decode(inst: UInt, table: Iterable[(UInt, List[UInt])]) = {
val decoder = DecodeLogic(inst, XDecode.decode_default, table)
Vec(legal, fp, rocc, branch, jal, jalr, rrs2, rrs1, sel_alu2, sel_alu1,
sel_imm, alu_dw, alu_fn, mem, mem_cmd, mem_type, mul, div, wrd, csr,
fence_i, sret, scall, replay_next, fence, amo) := decoder
this
}
}
object XDecode extends DecodeConstants
{
val table = Array(
@ -321,12 +354,8 @@ class Control extends Module
if (!params(BuildFPU).isEmpty) decode_table ++= FDecode.table
if (!params(BuildRoCC).isEmpty) decode_table ++= RoCCDecode.table
val cs = DecodeLogic(io.dpath.inst, XDecode.decode_default, decode_table)
val (id_int_val: Bool) :: (id_fp_val: Bool) :: (id_rocc_val: Bool) :: (id_branch: Bool) :: (id_jal: Bool) :: (id_jalr: Bool) :: (id_renx2: Bool) :: (id_renx1: Bool) :: cs0 = cs
val id_sel_alu2 :: id_sel_alu1 :: id_sel_imm :: (id_fn_dw: Bool) :: id_fn_alu :: cs1 = cs0
val (id_mem_val: Bool) :: id_mem_cmd :: id_mem_type :: (id_mul_val: Bool) :: (id_div_val: Bool) :: (id_wen: Bool) :: cs2 = cs1
val id_csr :: (id_fence_i: Bool) :: (id_sret: Bool) :: (id_syscall: Bool) :: (id_replay_next: Bool) :: (id_fence: Bool) :: (id_amo: Bool) :: Nil = cs2
val id_ctrl = new IntCtrlSigs().decode(io.dpath.inst, decode_table)
val ex_ctrl = Reg(new IntCtrlSigs)
val ex_reg_xcpt_interrupt = Reg(Bool())
val ex_reg_valid = Reg(Bool())
@ -418,9 +447,9 @@ class Control extends Module
val id_csr_addr = io.dpath.inst(31,20)
val isLegalCSR = Vec.tabulate(1 << id_csr_addr.getWidth)(i => Bool(legal_csrs contains i))
val id_csr_en = id_csr != CSR.N
val id_csr_en = id_ctrl.csr != CSR.N
val id_csr_fp = Bool(!params(BuildFPU).isEmpty) && id_csr_en && DecodeLogic(id_csr_addr, fp_csrs, CSRs.all.toSet -- fp_csrs)
val id_csr_wen = id_raddr1 != UInt(0) || !Vec(CSR.S, CSR.C).contains(id_csr)
val id_csr_wen = id_raddr1 != UInt(0) || !Vec(CSR.S, CSR.C).contains(id_ctrl.csr)
val id_csr_invalid = id_csr_en && !isLegalCSR(id_csr_addr)
val id_csr_privileged = id_csr_en &&
(id_csr_addr(11,10) === UInt(3) && id_csr_wen ||
@ -437,24 +466,24 @@ class Control extends Module
// stall decode for fences (now, for AMO.aq; later, for AMO.rl and FENCE)
val id_amo_aq = io.dpath.inst(26)
val id_amo_rl = io.dpath.inst(25)
val id_fence_next = id_fence || id_amo && id_amo_rl
val id_fence_next = id_ctrl.fence || id_ctrl.amo && id_amo_rl
val id_mem_busy = !io.dmem.ordered || ex_reg_mem_val
val id_rocc_busy = Bool(!params(BuildRoCC).isEmpty) &&
(io.rocc.busy || ex_reg_rocc_val || mem_reg_rocc_val || wb_reg_rocc_val)
id_reg_fence := id_fence_next || id_reg_fence && id_mem_busy
val id_do_fence = id_rocc_busy && id_fence ||
id_mem_busy && (id_amo && id_amo_aq || id_fence_i || id_reg_fence && (id_mem_val || id_rocc_val) || id_csr_flush)
val id_do_fence = id_rocc_busy && id_ctrl.fence ||
id_mem_busy && (id_ctrl.amo && id_amo_aq || id_ctrl.fence_i || id_reg_fence && (id_ctrl.mem || id_ctrl.rocc) || id_csr_flush)
val (id_xcpt, id_cause) = checkExceptions(List(
(id_interrupt, id_interrupt_cause),
(io.imem.resp.bits.xcpt_ma, UInt(Causes.misaligned_fetch)),
(io.imem.resp.bits.xcpt_if, UInt(Causes.fault_fetch)),
(!id_int_val || id_csr_invalid, UInt(Causes.illegal_instruction)),
(!id_ctrl.legal || id_csr_invalid, UInt(Causes.illegal_instruction)),
(id_csr_privileged, UInt(Causes.privileged_instruction)),
(id_sret && !io.dpath.status.s, UInt(Causes.privileged_instruction)),
((id_fp_val || id_csr_fp) && !io.dpath.status.ef, UInt(Causes.fp_disabled)),
(id_syscall, UInt(Causes.syscall)),
(id_rocc_val && !io.dpath.status.er, UInt(Causes.accelerator_disabled))))
(id_ctrl.sret && !io.dpath.status.s, UInt(Causes.privileged_instruction)),
((id_ctrl.fp || id_csr_fp) && !io.dpath.status.ef,UInt(Causes.fp_disabled)),
(id_ctrl.scall, UInt(Causes.syscall)),
(id_ctrl.rocc && !io.dpath.status.er, UInt(Causes.accelerator_disabled))))
ex_reg_xcpt_interrupt := id_interrupt && !take_pc && io.imem.resp.valid
when (id_xcpt) { ex_reg_cause := id_cause }
@ -479,25 +508,26 @@ class Control extends Module
ex_reg_xcpt := Bool(false)
}
.otherwise {
ex_reg_branch := id_branch
ex_reg_jal := id_jal
ex_reg_jalr := id_jalr
ex_ctrl := id_ctrl
ex_reg_branch := id_ctrl.branch
ex_reg_jal := id_ctrl.jal
ex_reg_jalr := id_ctrl.jalr
ex_reg_btb_hit := io.imem.btb_resp.valid
when (io.imem.btb_resp.valid) { ex_reg_btb_resp := io.imem.btb_resp.bits }
ex_reg_div_mul_val := id_mul_val || id_div_val
ex_reg_mem_val := id_mem_val.toBool
ex_reg_div_mul_val := id_ctrl.mul || id_ctrl.div
ex_reg_mem_val := id_ctrl.mem
ex_reg_valid := Bool(true)
ex_reg_csr := id_csr
ex_reg_wen := id_wen
ex_reg_fp_wen := id_fp_val && io.fpu.dec.wen
ex_reg_sret := id_sret
ex_reg_flush_inst := id_fence_i
ex_reg_fp_val := id_fp_val
ex_reg_rocc_val := id_rocc_val.toBool
ex_reg_replay_next := id_replay_next || id_csr_flush
ex_reg_csr := id_ctrl.csr
ex_reg_wen := id_ctrl.wrd
ex_reg_fp_wen := id_ctrl.fp && io.fpu.dec.wen
ex_reg_sret := id_ctrl.sret
ex_reg_flush_inst := id_ctrl.fence_i
ex_reg_fp_val := id_ctrl.fp
ex_reg_rocc_val := id_ctrl.rocc
ex_reg_replay_next := id_ctrl.replay_next || id_csr_flush
ex_reg_load_use := id_load_use
ex_reg_mem_cmd := id_mem_cmd
ex_reg_mem_type := id_mem_type.toUInt
ex_reg_mem_cmd := id_ctrl.mem_cmd
ex_reg_mem_type := id_ctrl.mem_type
ex_reg_xcpt := id_xcpt
}
@ -675,9 +705,9 @@ class Control extends Module
}
// stall for RAW/WAW hazards on PCRs, loads, AMOs, and mul/div in execute stage.
val id_renx1_not0 = id_renx1 && id_raddr1 != UInt(0)
val id_renx2_not0 = id_renx2 && id_raddr2 != UInt(0)
val id_wen_not0 = id_wen && id_waddr != UInt(0)
val id_renx1_not0 = id_ctrl.rrs1 && id_raddr1 != UInt(0)
val id_renx2_not0 = id_ctrl.rrs2 && id_raddr2 != UInt(0)
val id_wen_not0 = id_ctrl.wrd && id_waddr != UInt(0)
val data_hazard_ex = ex_reg_wen &&
(id_renx1_not0 && id_raddr1 === io.dpath.ex_waddr ||
id_renx2_not0 && id_raddr2 === io.dpath.ex_waddr ||
@ -729,8 +759,8 @@ class Control extends Module
val ctrl_stalld =
id_ex_hazard || id_mem_hazard || id_wb_hazard || id_sboard_hazard ||
id_fp_val && id_stall_fpu ||
id_mem_val && !io.dmem.req.ready ||
id_ctrl.fp && id_stall_fpu ||
id_ctrl.mem && !io.dmem.req.ready ||
id_do_fence
val ctrl_draind = id_interrupt || ex_reg_replay_next
ctrl_killd := !io.imem.resp.valid || take_pc || ctrl_stalld || ctrl_draind
@ -741,13 +771,9 @@ class Control extends Module
io.dpath.mem_load := mem_reg_mem_val && mem_reg_wen
io.dpath.wb_load := wb_reg_mem_val && wb_reg_wen
io.dpath.ren(1) := id_renx2
io.dpath.ren(0) := id_renx1
io.dpath.sel_alu2 := id_sel_alu2.toUInt
io.dpath.sel_alu1 := id_sel_alu1.toUInt
io.dpath.sel_imm := id_sel_imm.toUInt
io.dpath.fn_dw := id_fn_dw.toBool
io.dpath.fn_alu := id_fn_alu.toUInt
io.dpath.ren(1) := id_ctrl.rrs2
io.dpath.ren(0) := id_ctrl.rrs1
io.dpath.ex_ctrl := ex_ctrl
io.dpath.div_mul_val := ex_reg_div_mul_val
io.dpath.div_mul_kill := mem_reg_div_mul_val && killm_common
io.dpath.ex_fp_val:= ex_reg_fp_val
@ -767,7 +793,7 @@ class Control extends Module
io.dpath.ex_rocc_val := ex_reg_rocc_val
io.dpath.mem_rocc_val := mem_reg_rocc_val
io.fpu.valid := !ctrl_killd && id_fp_val
io.fpu.valid := !ctrl_killd && id_ctrl.fp
io.fpu.killx := ctrl_killx
io.fpu.killm := killm_common

View File

@ -22,11 +22,6 @@ class Datapath extends Module
// execute definitions
val ex_reg_pc = Reg(UInt())
val ex_reg_inst = Reg(Bits())
val ex_reg_ctrl_fn_dw = Reg(UInt())
val ex_reg_ctrl_fn_alu = Reg(UInt())
val ex_reg_sel_alu2 = Reg(UInt())
val ex_reg_sel_alu1 = Reg(UInt())
val ex_reg_sel_imm = Reg(UInt())
val ex_reg_kill = Reg(Bool())
val ex_reg_rs_bypass = Vec.fill(2)(Reg(Bool()))
val ex_reg_rs_lsb = Vec.fill(2)(Reg(Bits()))
@ -102,11 +97,6 @@ class Datapath extends Module
when (!io.ctrl.killd) {
ex_reg_pc := id_pc
ex_reg_inst := id_inst
ex_reg_ctrl_fn_dw := io.ctrl.fn_dw.toUInt
ex_reg_ctrl_fn_alu := io.ctrl.fn_alu
ex_reg_sel_alu2 := io.ctrl.sel_alu2
ex_reg_sel_alu1 := io.ctrl.sel_alu1
ex_reg_sel_imm := io.ctrl.sel_imm
ex_reg_rs_bypass := io.ctrl.bypass
for (i <- 0 until id_rs.size) {
when (io.ctrl.ren(i)) {
@ -129,18 +119,18 @@ class Datapath extends Module
val ex_rs = for (i <- 0 until id_rs.size)
yield Mux(ex_reg_rs_bypass(i), bypass(ex_reg_rs_lsb(i)), Cat(ex_reg_rs_msb(i), ex_reg_rs_lsb(i)))
val ex_imm = imm(ex_reg_sel_imm, ex_reg_inst)
val ex_op1 = MuxLookup(ex_reg_sel_alu1, SInt(0), Seq(
val ex_imm = imm(io.ctrl.ex_ctrl.sel_imm, ex_reg_inst)
val ex_op1 = MuxLookup(io.ctrl.ex_ctrl.sel_alu1, SInt(0), Seq(
A1_RS1 -> ex_rs(0).toSInt,
A1_PC -> ex_reg_pc.toSInt))
val ex_op2 = MuxLookup(ex_reg_sel_alu2, SInt(0), Seq(
val ex_op2 = MuxLookup(io.ctrl.ex_ctrl.sel_alu2, SInt(0), Seq(
A2_RS2 -> ex_rs(1).toSInt,
A2_IMM -> ex_imm,
A2_FOUR -> SInt(4)))
val alu = Module(new ALU)
alu.io.dw := ex_reg_ctrl_fn_dw
alu.io.fn := ex_reg_ctrl_fn_alu
alu.io.dw := io.ctrl.ex_ctrl.alu_dw
alu.io.fn := io.ctrl.ex_ctrl.alu_fn
alu.io.in2 := ex_op2.toUInt
alu.io.in1 := ex_op1
@ -148,8 +138,8 @@ class Datapath extends Module
val div = Module(new MulDiv(mulUnroll = if(params(FastMulDiv)) 8 else 1,
earlyOut = params(FastMulDiv)))
div.io.req.valid := io.ctrl.div_mul_val
div.io.req.bits.dw := ex_reg_ctrl_fn_dw
div.io.req.bits.fn := ex_reg_ctrl_fn_alu
div.io.req.bits.dw := io.ctrl.ex_ctrl.alu_dw
div.io.req.bits.fn := io.ctrl.ex_ctrl.alu_fn
div.io.req.bits.in1 := ex_rs(0)
div.io.req.bits.in2 := ex_rs(1)
div.io.req.bits.tag := io.ctrl.ex_waddr