Refactor pipeline RTL (merge ctrl + dpath into rocket)
This commit is contained in:
Andrew Waterman
parent
ac6e73e317
commit
cc447c8110
@ -18,11 +18,6 @@ trait ScalarOpConstants {
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val BR_LTU = Bits(6, 3)
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val BR_LTU = Bits(6, 3)
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val BR_GEU = Bits(7, 3)
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val BR_GEU = Bits(7, 3)
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val PC_EX = UInt(0, 2)
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val PC_MEM = UInt(1, 2)
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val PC_WB = UInt(2, 2)
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val PC_CSR = UInt(3, 2)
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val A1_X = Bits("b??", 2)
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val A1_X = Bits("b??", 2)
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val A1_ZERO = UInt(0, 2)
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val A1_ZERO = UInt(0, 2)
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val A1_RS1 = UInt(1, 2)
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val A1_RS1 = UInt(1, 2)
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@ -46,13 +41,6 @@ trait ScalarOpConstants {
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val N = Bool(false)
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val N = Bool(false)
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val Y = Bool(true)
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val Y = Bool(true)
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val NBYP = 4
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val SZ_BYP = log2Up(NBYP)
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val BYP_0 = 0
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val BYP_EX = 1
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val BYP_MEM = 2
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val BYP_DC = 3
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val SZ_DW = 1
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val SZ_DW = 1
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val DW_X = X
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val DW_X = X
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val DW_32 = N
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val DW_32 = N
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@ -1,94 +0,0 @@
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// See LICENSE for license details.
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package rocket
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import Chisel._
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import Util._
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import uncore._
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case object BuildFPU extends Field[Option[() => FPU]]
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case object FDivSqrt extends Field[Boolean]
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case object XLen extends Field[Int]
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case object NMultXpr extends Field[Int]
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case object FetchWidth extends Field[Int]
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case object RetireWidth extends Field[Int]
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case object UseVM extends Field[Boolean]
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case object FastLoadWord extends Field[Boolean]
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case object FastLoadByte extends Field[Boolean]
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case object FastMulDiv extends Field[Boolean]
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case object CoreInstBits extends Field[Int]
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case object CoreDataBits extends Field[Int]
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case object CoreDCacheReqTagBits extends Field[Int]
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case object NCustomMRWCSRs extends Field[Int]
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abstract trait CoreParameters extends UsesParameters {
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val xLen = params(XLen)
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val paddrBits = params(PAddrBits)
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val vaddrBits = params(VAddrBits)
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val pgIdxBits = params(PgIdxBits)
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val ppnBits = params(PPNBits)
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val vpnBits = params(VPNBits)
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val pgLevels = params(PgLevels)
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val pgLevelBits = params(PgLevelBits)
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val asIdBits = params(ASIdBits)
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val retireWidth = params(RetireWidth)
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val coreFetchWidth = params(FetchWidth)
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val coreInstBits = params(CoreInstBits)
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val coreInstBytes = coreInstBits/8
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val coreDataBits = xLen
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val coreDataBytes = coreDataBits/8
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val coreDCacheReqTagBits = params(CoreDCacheReqTagBits)
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val coreMaxAddrBits = math.max(ppnBits,vpnBits+1) + pgIdxBits
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val vaddrBitsExtended = vaddrBits + (vaddrBits < xLen).toInt
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if(params(FastLoadByte)) require(params(FastLoadWord))
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}
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abstract trait RocketCoreParameters extends CoreParameters
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{
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require(params(FetchWidth) == 1) // for now...
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require(params(RetireWidth) == 1) // for now...
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}
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abstract class CoreBundle extends Bundle with CoreParameters
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abstract class CoreModule extends Module with CoreParameters
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class RocketIO extends Bundle
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{
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val host = new HTIFIO
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val imem = new CPUFrontendIO
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val dmem = new HellaCacheIO
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val ptw = new DatapathPTWIO().flip
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val rocc = new RoCCInterface().flip
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}
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class Core extends Module with CoreParameters
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{
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val io = new RocketIO
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val ctrl = Module(new Control)
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val dpath = Module(new Datapath)
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//If so specified, build an FPU module and wire it in
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params(BuildFPU)
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.map { bf => bf() }
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.foreach { fpu =>
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dpath.io.fpu <> fpu.io.dpath
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ctrl.io.fpu <> fpu.io.ctrl
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}
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ctrl.io.dpath <> dpath.io.ctrl
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dpath.io.host <> io.host
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ctrl.io.imem <> io.imem
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dpath.io.imem <> io.imem
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ctrl.io.dmem <> io.dmem
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dpath.io.dmem <> io.dmem
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dpath.io.ptw <> io.ptw
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ctrl.io.rocc <> io.rocc
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dpath.io.rocc <> io.rocc
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}
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@ -1,291 +0,0 @@
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// See LICENSE for license details.
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package rocket
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import Chisel._
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import Instructions._
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import Util._
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import uncore._
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class Datapath extends CoreModule
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{
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val io = new Bundle {
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val host = new HTIFIO
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val ctrl = new CtrlDpathIO().flip
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val dmem = new HellaCacheIO
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val ptw = new DatapathPTWIO().flip
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val imem = new CPUFrontendIO
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val fpu = new DpathFPUIO
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val rocc = new RoCCInterface().flip
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}
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// execute definitions
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val ex_reg_pc = Reg(UInt())
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val ex_reg_inst = Reg(Bits())
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val ex_reg_kill = Reg(Bool())
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val ex_reg_rs_bypass = Reg(Vec.fill(2)(Bool()))
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val ex_reg_rs_lsb = Reg(Vec.fill(2)(Bits()))
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val ex_reg_rs_msb = Reg(Vec.fill(2)(Bits()))
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// memory definitions
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val mem_reg_pc = Reg(UInt())
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val mem_reg_inst = Reg(Bits())
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val mem_reg_wdata = Reg(Bits())
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val mem_reg_kill = Reg(Bool())
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val mem_reg_rs2 = Reg(Bits())
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// writeback definitions
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val wb_reg_pc = Reg(UInt())
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val wb_reg_inst = Reg(Bits())
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val wb_reg_wdata = Reg(Bits())
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val wb_wdata = Wire(Bits())
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val wb_reg_rs2 = Reg(Bits())
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// instruction decode stage
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val id_inst = io.imem.resp.bits.data(0).toBits; require(params(FetchWidth) == 1)
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val id_pc = io.imem.resp.bits.pc
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class RegFile {
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private val rf = Mem(UInt(width = 64), 31)
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private val reads = collection.mutable.ArrayBuffer[(UInt,UInt)]()
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private var canRead = true
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def read(addr: UInt) = {
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require(canRead)
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reads += addr -> Wire(UInt())
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reads.last._2 := rf(~addr)
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reads.last._2
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}
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def write(addr: UInt, data: UInt) = {
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canRead = false
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when (addr != UInt(0)) {
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rf(~addr) := data
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for ((raddr, rdata) <- reads)
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when (addr === raddr) { rdata := data }
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}
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}
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}
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val rf = new RegFile
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// RF read ports + bypass from WB stage
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val id_raddr = Vec(id_inst(19,15), id_inst(24,20))
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val id_rs = id_raddr.map(rf.read _)
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// immediate generation
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def imm(sel: Bits, inst: Bits) = {
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val sign = Mux(sel === IMM_Z, SInt(0), inst(31).toSInt)
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val b30_20 = Mux(sel === IMM_U, inst(30,20).toSInt, sign)
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val b19_12 = Mux(sel != IMM_U && sel != IMM_UJ, sign, inst(19,12).toSInt)
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val b11 = Mux(sel === IMM_U || sel === IMM_Z, SInt(0),
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Mux(sel === IMM_UJ, inst(20).toSInt,
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Mux(sel === IMM_SB, inst(7).toSInt, sign)))
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val b10_5 = Mux(sel === IMM_U || sel === IMM_Z, Bits(0), inst(30,25))
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val b4_1 = Mux(sel === IMM_U, Bits(0),
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Mux(sel === IMM_S || sel === IMM_SB, inst(11,8),
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Mux(sel === IMM_Z, inst(19,16), inst(24,21))))
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val b0 = Mux(sel === IMM_S, inst(7),
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Mux(sel === IMM_I, inst(20),
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Mux(sel === IMM_Z, inst(15), Bits(0))))
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Cat(sign, b30_20, b19_12, b11, b10_5, b4_1, b0).toSInt
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}
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io.ctrl.inst := id_inst
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io.fpu.inst := id_inst
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// execute stage
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ex_reg_kill := io.ctrl.killd
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when (!io.ctrl.killd) {
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ex_reg_pc := id_pc
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ex_reg_inst := id_inst
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ex_reg_rs_bypass := io.ctrl.bypass
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for (i <- 0 until id_rs.size) {
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when (io.ctrl.ren(i)) {
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ex_reg_rs_lsb(i) := id_rs(i)(SZ_BYP-1,0)
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when (!io.ctrl.bypass(i)) {
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ex_reg_rs_msb(i) := id_rs(i) >> SZ_BYP
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}
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}
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when (io.ctrl.bypass(i)) { ex_reg_rs_lsb(i) := io.ctrl.bypass_src(i) }
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}
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}
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val bypass = Wire(Vec(Bits(), NBYP))
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bypass(BYP_0) := Bits(0)
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bypass(BYP_EX) := mem_reg_wdata
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bypass(BYP_MEM) := wb_reg_wdata
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bypass(BYP_DC) := (if(params(FastLoadByte)) io.dmem.resp.bits.data_subword
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else if(params(FastLoadWord)) io.dmem.resp.bits.data
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else wb_reg_wdata)
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val ex_rs = for (i <- 0 until id_rs.size)
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yield Mux(ex_reg_rs_bypass(i), bypass(ex_reg_rs_lsb(i)), Cat(ex_reg_rs_msb(i), ex_reg_rs_lsb(i)))
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val ex_imm = imm(io.ctrl.ex_ctrl.sel_imm, ex_reg_inst)
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val ex_op1 = MuxLookup(io.ctrl.ex_ctrl.sel_alu1, SInt(0), Seq(
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A1_RS1 -> ex_rs(0).toSInt,
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A1_PC -> ex_reg_pc.toSInt))
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val ex_op2 = MuxLookup(io.ctrl.ex_ctrl.sel_alu2, SInt(0), Seq(
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A2_RS2 -> ex_rs(1).toSInt,
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A2_IMM -> ex_imm,
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A2_FOUR -> SInt(4)))
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val alu = Module(new ALU)
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alu.io.dw := io.ctrl.ex_ctrl.alu_dw
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alu.io.fn := io.ctrl.ex_ctrl.alu_fn
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alu.io.in2 := ex_op2.toUInt
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alu.io.in1 := ex_op1
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// multiplier and divider
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val div = Module(new MulDiv(mulUnroll = if(params(FastMulDiv)) 8 else 1,
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earlyOut = params(FastMulDiv)))
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div.io.req.valid := io.ctrl.ex_valid && io.ctrl.ex_ctrl.div
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div.io.req.bits.dw := io.ctrl.ex_ctrl.alu_dw
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div.io.req.bits.fn := io.ctrl.ex_ctrl.alu_fn
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div.io.req.bits.in1 := ex_rs(0)
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div.io.req.bits.in2 := ex_rs(1)
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div.io.req.bits.tag := io.ctrl.ex_waddr
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div.io.kill := io.ctrl.killm && Reg(next = div.io.req.fire())
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io.ctrl.div_mul_rdy := div.io.req.ready
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io.fpu.fromint_data := ex_rs(0)
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def vaSign(a0: UInt, ea: Bits) = {
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// efficient means to compress 64-bit VA into vaddrBits+1 bits
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// (VA is bad if VA(vaddrBits) != VA(vaddrBits-1))
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val a = a0 >> vaddrBits-1
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val e = ea(vaddrBits,vaddrBits-1)
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Mux(a === UInt(0) || a === UInt(1), e != UInt(0),
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Mux(a === SInt(-1) || a === SInt(-2), e === SInt(-1),
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e(0)))
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}
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// D$ request interface (registered inside D$ module)
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// other signals (req_val, req_rdy) connect to control module
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io.dmem.req.bits.addr := Cat(vaSign(ex_rs(0), alu.io.adder_out), alu.io.adder_out(vaddrBits-1,0)).toUInt
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io.dmem.req.bits.tag := Cat(io.ctrl.ex_waddr, io.ctrl.ex_ctrl.fp)
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require(io.dmem.req.bits.tag.getWidth >= 6)
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require(params(CoreDCacheReqTagBits) >= 6)
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// processor control regfile read
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val csr = Module(new CSRFile)
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csr.io.host <> io.host
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csr.io <> io.ctrl
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csr.io <> io.fpu
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csr.io.rocc <> io.rocc
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csr.io.pc := wb_reg_pc
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csr.io.uarch_counters.foreach(_ := Bool(false))
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io.ptw.ptbr := csr.io.ptbr
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io.ptw.invalidate := csr.io.fatc
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io.ptw.status := csr.io.status
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// memory stage
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mem_reg_kill := ex_reg_kill
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when (!ex_reg_kill) {
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mem_reg_pc := ex_reg_pc
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mem_reg_inst := ex_reg_inst
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mem_reg_wdata := alu.io.out
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when (io.ctrl.ex_ctrl.rxs2 && (io.ctrl.ex_ctrl.mem || io.ctrl.ex_ctrl.rocc)) {
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mem_reg_rs2 := ex_rs(1)
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}
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}
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io.dmem.req.bits.data := Mux(io.ctrl.mem_ctrl.fp, io.fpu.store_data, mem_reg_rs2)
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// writeback arbitration
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val dmem_resp_xpu = !io.dmem.resp.bits.tag(0).toBool
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val dmem_resp_fpu = io.dmem.resp.bits.tag(0).toBool
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val dmem_resp_waddr = io.dmem.resp.bits.tag.toUInt >> UInt(1)
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val dmem_resp_valid = io.dmem.resp.valid && io.dmem.resp.bits.has_data
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val dmem_resp_replay = io.dmem.resp.bits.replay && io.dmem.resp.bits.has_data
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val ll_wdata = Wire(Bits())
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div.io.resp.ready := io.ctrl.ll_ready
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ll_wdata := div.io.resp.bits.data
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io.ctrl.ll_waddr := div.io.resp.bits.tag
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io.ctrl.ll_wen := div.io.resp.fire()
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if (!params(BuildRoCC).isEmpty) {
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io.rocc.resp.ready := io.ctrl.ll_ready
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when (io.rocc.resp.fire()) {
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div.io.resp.ready := Bool(false)
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ll_wdata := io.rocc.resp.bits.data
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io.ctrl.ll_waddr := io.rocc.resp.bits.rd
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io.ctrl.ll_wen := Bool(true)
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}
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}
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when (dmem_resp_replay && dmem_resp_xpu) {
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div.io.resp.ready := Bool(false)
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if (!params(BuildRoCC).isEmpty)
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io.rocc.resp.ready := Bool(false)
|
|
||||||
io.ctrl.ll_waddr := dmem_resp_waddr
|
|
||||||
io.ctrl.ll_wen := Bool(true)
|
|
||||||
}
|
|
||||||
|
|
||||||
io.fpu.dmem_resp_val := dmem_resp_valid && dmem_resp_fpu
|
|
||||||
io.fpu.dmem_resp_data := io.dmem.resp.bits.data
|
|
||||||
io.fpu.dmem_resp_type := io.dmem.resp.bits.typ
|
|
||||||
io.fpu.dmem_resp_tag := dmem_resp_waddr
|
|
||||||
|
|
||||||
io.ctrl.mem_br_taken := mem_reg_wdata(0)
|
|
||||||
val mem_br_target = mem_reg_pc.toSInt +
|
|
||||||
Mux(io.ctrl.mem_ctrl.branch && io.ctrl.mem_br_taken, imm(IMM_SB, mem_reg_inst),
|
|
||||||
Mux(io.ctrl.mem_ctrl.jal, imm(IMM_UJ, mem_reg_inst), SInt(4)))
|
|
||||||
val mem_npc = (Mux(io.ctrl.mem_ctrl.jalr, Cat(vaSign(mem_reg_wdata, mem_reg_wdata), mem_reg_wdata(vaddrBits-1,0)).toSInt, mem_br_target) & SInt(-2)).toUInt
|
|
||||||
io.ctrl.mem_misprediction := mem_npc != ex_reg_pc || !io.ctrl.ex_valid
|
|
||||||
io.ctrl.mem_npc_misaligned := mem_npc(1)
|
|
||||||
io.ctrl.mem_rs1_ra := mem_reg_inst(19,15) === 1
|
|
||||||
val mem_int_wdata = Mux(io.ctrl.mem_ctrl.jalr, mem_br_target, mem_reg_wdata.toSInt).toUInt
|
|
||||||
|
|
||||||
// writeback stage
|
|
||||||
when (!mem_reg_kill) {
|
|
||||||
wb_reg_pc := mem_reg_pc
|
|
||||||
wb_reg_inst := mem_reg_inst
|
|
||||||
wb_reg_wdata := Mux(io.ctrl.mem_ctrl.fp && io.ctrl.mem_ctrl.wxd, io.fpu.toint_data, mem_int_wdata)
|
|
||||||
when (io.ctrl.mem_ctrl.rocc) {
|
|
||||||
wb_reg_rs2 := mem_reg_rs2
|
|
||||||
}
|
|
||||||
}
|
|
||||||
wb_wdata := Mux(dmem_resp_valid && dmem_resp_xpu, io.dmem.resp.bits.data_subword,
|
|
||||||
Mux(io.ctrl.ll_wen, ll_wdata,
|
|
||||||
Mux(io.ctrl.csr_cmd != CSR.N, csr.io.rw.rdata,
|
|
||||||
wb_reg_wdata)))
|
|
||||||
|
|
||||||
val wb_wen = io.ctrl.ll_wen || io.ctrl.wb_wen
|
|
||||||
val wb_waddr = Mux(io.ctrl.ll_wen, io.ctrl.ll_waddr, io.ctrl.wb_waddr)
|
|
||||||
when (wb_wen) { rf.write(wb_waddr, wb_wdata) }
|
|
||||||
|
|
||||||
// scoreboard clear (for div/mul and D$ load miss writebacks)
|
|
||||||
io.ctrl.fp_sboard_clr := dmem_resp_replay && dmem_resp_fpu
|
|
||||||
io.ctrl.fp_sboard_clra := dmem_resp_waddr
|
|
||||||
|
|
||||||
// processor control regfile write
|
|
||||||
csr.io.rw.addr := wb_reg_inst(31,20)
|
|
||||||
csr.io.rw.cmd := io.ctrl.csr_cmd
|
|
||||||
csr.io.rw.wdata := wb_reg_wdata
|
|
||||||
|
|
||||||
io.rocc.cmd.bits.inst := new RoCCInstruction().fromBits(wb_reg_inst)
|
|
||||||
io.rocc.cmd.bits.rs1 := wb_reg_wdata
|
|
||||||
io.rocc.cmd.bits.rs2 := wb_reg_rs2
|
|
||||||
|
|
||||||
// hook up I$
|
|
||||||
io.imem.req.bits.pc :=
|
|
||||||
Mux(io.ctrl.sel_pc === PC_MEM, mem_npc,
|
|
||||||
Mux(io.ctrl.sel_pc === PC_CSR, csr.io.evec,
|
|
||||||
wb_reg_pc)).toUInt // PC_WB
|
|
||||||
io.imem.btb_update.bits.pc := mem_reg_pc
|
|
||||||
io.imem.btb_update.bits.target := io.imem.req.bits.pc
|
|
||||||
io.imem.btb_update.bits.br_pc := mem_reg_pc
|
|
||||||
io.imem.bht_update.bits.pc := mem_reg_pc
|
|
||||||
io.imem.ras_update.bits.returnAddr := mem_int_wdata
|
|
||||||
|
|
||||||
// for hazard/bypass opportunity detection
|
|
||||||
io.ctrl.ex_waddr := ex_reg_inst(11,7)
|
|
||||||
io.ctrl.mem_waddr := mem_reg_inst(11,7)
|
|
||||||
io.ctrl.wb_waddr := wb_reg_inst(11,7)
|
|
||||||
|
|
||||||
printf("C%d: %d [%d] pc=[%x] W[r%d=%x][%d] R[r%d=%x] R[r%d=%x] inst=[%x] DASM(%x)\n",
|
|
||||||
io.host.id, csr.io.time(32,0), io.ctrl.retire, wb_reg_pc,
|
|
||||||
Mux(wb_wen, wb_waddr, UInt(0)), wb_wdata, wb_wen,
|
|
||||||
wb_reg_inst(19,15), Reg(next=Reg(next=ex_rs(0))),
|
|
||||||
wb_reg_inst(24,20), Reg(next=Reg(next=ex_rs(1))),
|
|
||||||
wb_reg_inst, wb_reg_inst)
|
|
||||||
}
|
|
||||||
@ -138,33 +138,34 @@ class FPUDecoder extends Module
|
|||||||
s.toint, s.fastpipe, s.fma, s.div, s.sqrt, s.round, s.wflags) := decoder
|
s.toint, s.fastpipe, s.fma, s.div, s.sqrt, s.round, s.wflags) := decoder
|
||||||
}
|
}
|
||||||
|
|
||||||
class DpathFPUIO extends Bundle {
|
class FPUIO extends Bundle {
|
||||||
val inst = Bits(OUTPUT, 32)
|
val inst = Bits(INPUT, 32)
|
||||||
val fromint_data = Bits(OUTPUT, 64)
|
val fromint_data = Bits(INPUT, 64)
|
||||||
|
|
||||||
val fcsr_rm = Bits(OUTPUT, FPConstants.RM_SZ)
|
val fcsr_rm = Bits(INPUT, FPConstants.RM_SZ)
|
||||||
val fcsr_flags = Valid(Bits(width = FPConstants.FLAGS_SZ)).flip
|
val fcsr_flags = Valid(Bits(width = FPConstants.FLAGS_SZ))
|
||||||
|
|
||||||
val store_data = Bits(INPUT, 64)
|
val store_data = Bits(OUTPUT, 64)
|
||||||
val toint_data = Bits(INPUT, 64)
|
val toint_data = Bits(OUTPUT, 64)
|
||||||
|
|
||||||
val dmem_resp_val = Bool(OUTPUT)
|
val dmem_resp_val = Bool(INPUT)
|
||||||
val dmem_resp_type = Bits(OUTPUT, 3)
|
val dmem_resp_type = Bits(INPUT, 3)
|
||||||
val dmem_resp_tag = UInt(OUTPUT, 5)
|
val dmem_resp_tag = UInt(INPUT, 5)
|
||||||
val dmem_resp_data = Bits(OUTPUT, 64)
|
val dmem_resp_data = Bits(INPUT, 64)
|
||||||
|
|
||||||
|
val valid = Bool(INPUT)
|
||||||
|
val fcsr_rdy = Bool(OUTPUT)
|
||||||
|
val nack_mem = Bool(OUTPUT)
|
||||||
|
val illegal_rm = Bool(OUTPUT)
|
||||||
|
val killx = Bool(INPUT)
|
||||||
|
val killm = Bool(INPUT)
|
||||||
|
val dec = new FPUCtrlSigs().asOutput
|
||||||
|
val sboard_set = Bool(OUTPUT)
|
||||||
|
val sboard_clr = Bool(OUTPUT)
|
||||||
|
val sboard_clra = UInt(OUTPUT, 5)
|
||||||
}
|
}
|
||||||
|
|
||||||
class CtrlFPUIO extends Bundle {
|
class CtrlFPUIO extends Bundle {
|
||||||
val valid = Bool(OUTPUT)
|
|
||||||
val fcsr_rdy = Bool(INPUT)
|
|
||||||
val nack_mem = Bool(INPUT)
|
|
||||||
val illegal_rm = Bool(INPUT)
|
|
||||||
val killx = Bool(OUTPUT)
|
|
||||||
val killm = Bool(OUTPUT)
|
|
||||||
val dec = new FPUCtrlSigs().asInput
|
|
||||||
val sboard_set = Bool(INPUT)
|
|
||||||
val sboard_clr = Bool(INPUT)
|
|
||||||
val sboard_clra = UInt(INPUT, 5)
|
|
||||||
}
|
}
|
||||||
|
|
||||||
class FPResult extends Bundle
|
class FPResult extends Bundle
|
||||||
@ -355,31 +356,28 @@ class FPUFMAPipe(val latency: Int, sigWidth: Int, expWidth: Int) extends Module
|
|||||||
|
|
||||||
class FPU extends Module
|
class FPU extends Module
|
||||||
{
|
{
|
||||||
val io = new Bundle {
|
val io = new FPUIO
|
||||||
val ctrl = (new CtrlFPUIO).flip
|
|
||||||
val dpath = (new DpathFPUIO).flip
|
|
||||||
}
|
|
||||||
|
|
||||||
val ex_reg_valid = Reg(next=io.ctrl.valid, init=Bool(false))
|
val ex_reg_valid = Reg(next=io.valid, init=Bool(false))
|
||||||
val ex_reg_inst = RegEnable(io.dpath.inst, io.ctrl.valid)
|
val ex_reg_inst = RegEnable(io.inst, io.valid)
|
||||||
val mem_reg_valid = Reg(next=ex_reg_valid && !io.ctrl.killx, init=Bool(false))
|
val mem_reg_valid = Reg(next=ex_reg_valid && !io.killx, init=Bool(false))
|
||||||
val mem_reg_inst = RegEnable(ex_reg_inst, ex_reg_valid)
|
val mem_reg_inst = RegEnable(ex_reg_inst, ex_reg_valid)
|
||||||
val killm = io.ctrl.killm || io.ctrl.nack_mem
|
val killm = io.killm || io.nack_mem
|
||||||
val wb_reg_valid = Reg(next=mem_reg_valid && !killm, init=Bool(false))
|
val wb_reg_valid = Reg(next=mem_reg_valid && !killm, init=Bool(false))
|
||||||
|
|
||||||
val fp_decoder = Module(new FPUDecoder)
|
val fp_decoder = Module(new FPUDecoder)
|
||||||
fp_decoder.io.inst := io.dpath.inst
|
fp_decoder.io.inst := io.inst
|
||||||
|
|
||||||
val id_ctrl = fp_decoder.io.sigs
|
val id_ctrl = fp_decoder.io.sigs
|
||||||
val ex_ctrl = RegEnable(id_ctrl, io.ctrl.valid)
|
val ex_ctrl = RegEnable(id_ctrl, io.valid)
|
||||||
val mem_ctrl = RegEnable(ex_ctrl, ex_reg_valid)
|
val mem_ctrl = RegEnable(ex_ctrl, ex_reg_valid)
|
||||||
val wb_ctrl = RegEnable(mem_ctrl, mem_reg_valid)
|
val wb_ctrl = RegEnable(mem_ctrl, mem_reg_valid)
|
||||||
|
|
||||||
// load response
|
// load response
|
||||||
val load_wb = Reg(next=io.dpath.dmem_resp_val)
|
val load_wb = Reg(next=io.dmem_resp_val)
|
||||||
val load_wb_single = RegEnable(io.dpath.dmem_resp_type === MT_W || io.dpath.dmem_resp_type === MT_WU, io.dpath.dmem_resp_val)
|
val load_wb_single = RegEnable(io.dmem_resp_type === MT_W || io.dmem_resp_type === MT_WU, io.dmem_resp_val)
|
||||||
val load_wb_data = RegEnable(io.dpath.dmem_resp_data, io.dpath.dmem_resp_val)
|
val load_wb_data = RegEnable(io.dmem_resp_data, io.dmem_resp_val)
|
||||||
val load_wb_tag = RegEnable(io.dpath.dmem_resp_tag, io.dpath.dmem_resp_val)
|
val load_wb_tag = RegEnable(io.dmem_resp_tag, io.dmem_resp_val)
|
||||||
val rec_s = hardfloat.floatNToRecodedFloatN(load_wb_data, 23, 9)
|
val rec_s = hardfloat.floatNToRecodedFloatN(load_wb_data, 23, 9)
|
||||||
val rec_d = hardfloat.floatNToRecodedFloatN(load_wb_data, 52, 12)
|
val rec_d = hardfloat.floatNToRecodedFloatN(load_wb_data, 52, 12)
|
||||||
val load_wb_data_recoded = Mux(load_wb_single, Cat(SInt(-1, 32), rec_s), rec_d)
|
val load_wb_data_recoded = Mux(load_wb_single, Cat(SInt(-1, 32), rec_s), rec_d)
|
||||||
@ -389,20 +387,20 @@ class FPU extends Module
|
|||||||
when (load_wb) { regfile(load_wb_tag) := load_wb_data_recoded }
|
when (load_wb) { regfile(load_wb_tag) := load_wb_data_recoded }
|
||||||
|
|
||||||
val ex_ra1::ex_ra2::ex_ra3::Nil = List.fill(3)(Reg(UInt()))
|
val ex_ra1::ex_ra2::ex_ra3::Nil = List.fill(3)(Reg(UInt()))
|
||||||
when (io.ctrl.valid) {
|
when (io.valid) {
|
||||||
when (id_ctrl.ren1) {
|
when (id_ctrl.ren1) {
|
||||||
when (!id_ctrl.swap12) { ex_ra1 := io.dpath.inst(19,15) }
|
when (!id_ctrl.swap12) { ex_ra1 := io.inst(19,15) }
|
||||||
when (id_ctrl.swap12) { ex_ra2 := io.dpath.inst(19,15) }
|
when (id_ctrl.swap12) { ex_ra2 := io.inst(19,15) }
|
||||||
}
|
}
|
||||||
when (id_ctrl.ren2) {
|
when (id_ctrl.ren2) {
|
||||||
when (id_ctrl.swap12) { ex_ra1 := io.dpath.inst(24,20) }
|
when (id_ctrl.swap12) { ex_ra1 := io.inst(24,20) }
|
||||||
when (id_ctrl.swap23) { ex_ra3 := io.dpath.inst(24,20) }
|
when (id_ctrl.swap23) { ex_ra3 := io.inst(24,20) }
|
||||||
when (!id_ctrl.swap12 && !id_ctrl.swap23) { ex_ra2 := io.dpath.inst(24,20) }
|
when (!id_ctrl.swap12 && !id_ctrl.swap23) { ex_ra2 := io.inst(24,20) }
|
||||||
}
|
}
|
||||||
when (id_ctrl.ren3) { ex_ra3 := io.dpath.inst(31,27) }
|
when (id_ctrl.ren3) { ex_ra3 := io.inst(31,27) }
|
||||||
}
|
}
|
||||||
val ex_rs1::ex_rs2::ex_rs3::Nil = Seq(ex_ra1, ex_ra2, ex_ra3).map(regfile(_))
|
val ex_rs1::ex_rs2::ex_rs3::Nil = Seq(ex_ra1, ex_ra2, ex_ra3).map(regfile(_))
|
||||||
val ex_rm = Mux(ex_reg_inst(14,12) === Bits(7), io.dpath.fcsr_rm, ex_reg_inst(14,12))
|
val ex_rm = Mux(ex_reg_inst(14,12) === Bits(7), io.fcsr_rm, ex_reg_inst(14,12))
|
||||||
|
|
||||||
val req = Wire(new FPInput)
|
val req = Wire(new FPInput)
|
||||||
req := ex_ctrl
|
req := ex_ctrl
|
||||||
@ -423,13 +421,13 @@ class FPU extends Module
|
|||||||
val fpiu = Module(new FPToInt)
|
val fpiu = Module(new FPToInt)
|
||||||
fpiu.io.in.valid := ex_reg_valid && (ex_ctrl.toint || ex_ctrl.div || ex_ctrl.sqrt || ex_ctrl.cmd === FCMD_MINMAX)
|
fpiu.io.in.valid := ex_reg_valid && (ex_ctrl.toint || ex_ctrl.div || ex_ctrl.sqrt || ex_ctrl.cmd === FCMD_MINMAX)
|
||||||
fpiu.io.in.bits := req
|
fpiu.io.in.bits := req
|
||||||
io.dpath.store_data := fpiu.io.out.bits.store
|
io.store_data := fpiu.io.out.bits.store
|
||||||
io.dpath.toint_data := fpiu.io.out.bits.toint
|
io.toint_data := fpiu.io.out.bits.toint
|
||||||
|
|
||||||
val ifpu = Module(new IntToFP(3))
|
val ifpu = Module(new IntToFP(3))
|
||||||
ifpu.io.in.valid := ex_reg_valid && ex_ctrl.fromint
|
ifpu.io.in.valid := ex_reg_valid && ex_ctrl.fromint
|
||||||
ifpu.io.in.bits := req
|
ifpu.io.in.bits := req
|
||||||
ifpu.io.in.bits.in1 := io.dpath.fromint_data
|
ifpu.io.in.bits.in1 := io.fromint_data
|
||||||
|
|
||||||
val fpmu = Module(new FPToFP(2))
|
val fpmu = Module(new FPToFP(2))
|
||||||
fpmu.io.in.valid := ex_reg_valid && ex_ctrl.fastpipe
|
fpmu.io.in.valid := ex_reg_valid && ex_ctrl.fastpipe
|
||||||
@ -489,22 +487,22 @@ class FPU extends Module
|
|||||||
|
|
||||||
val wb_toint_valid = wb_reg_valid && wb_ctrl.toint
|
val wb_toint_valid = wb_reg_valid && wb_ctrl.toint
|
||||||
val wb_toint_exc = RegEnable(fpiu.io.out.bits.exc, mem_ctrl.toint)
|
val wb_toint_exc = RegEnable(fpiu.io.out.bits.exc, mem_ctrl.toint)
|
||||||
io.dpath.fcsr_flags.valid := wb_toint_valid || divSqrt_wen || wen(0)
|
io.fcsr_flags.valid := wb_toint_valid || divSqrt_wen || wen(0)
|
||||||
io.dpath.fcsr_flags.bits :=
|
io.fcsr_flags.bits :=
|
||||||
Mux(wb_toint_valid, wb_toint_exc, UInt(0)) |
|
Mux(wb_toint_valid, wb_toint_exc, UInt(0)) |
|
||||||
Mux(divSqrt_wen, divSqrt_flags, UInt(0)) |
|
Mux(divSqrt_wen, divSqrt_flags, UInt(0)) |
|
||||||
Mux(wen(0), wexc, UInt(0))
|
Mux(wen(0), wexc, UInt(0))
|
||||||
|
|
||||||
val units_busy = mem_reg_valid && (mem_ctrl.div || mem_ctrl.sqrt) && (!divSqrt_inReady || wen.orR) // || mem_reg_valid && mem_ctrl.fma && Reg(next=Mux(ex_ctrl.single, io.sfma.valid, io.dfma.valid))
|
val units_busy = mem_reg_valid && (mem_ctrl.div || mem_ctrl.sqrt) && (!divSqrt_inReady || wen.orR) // || mem_reg_valid && mem_ctrl.fma && Reg(next=Mux(ex_ctrl.single, io.sfma.valid, io.dfma.valid))
|
||||||
io.ctrl.fcsr_rdy := !(ex_reg_valid && ex_ctrl.wflags || mem_reg_valid && mem_ctrl.wflags || wb_reg_valid && wb_ctrl.toint || wen.orR || divSqrt_in_flight)
|
io.fcsr_rdy := !(ex_reg_valid && ex_ctrl.wflags || mem_reg_valid && mem_ctrl.wflags || wb_reg_valid && wb_ctrl.toint || wen.orR || divSqrt_in_flight)
|
||||||
io.ctrl.nack_mem := units_busy || write_port_busy || divSqrt_in_flight
|
io.nack_mem := units_busy || write_port_busy || divSqrt_in_flight
|
||||||
io.ctrl.dec <> fp_decoder.io.sigs
|
io.dec <> fp_decoder.io.sigs
|
||||||
def useScoreboard(f: ((Pipe, Int)) => Bool) = pipes.zipWithIndex.filter(_._1.lat > 3).map(x => f(x)).fold(Bool(false))(_||_)
|
def useScoreboard(f: ((Pipe, Int)) => Bool) = pipes.zipWithIndex.filter(_._1.lat > 3).map(x => f(x)).fold(Bool(false))(_||_)
|
||||||
io.ctrl.sboard_set := wb_reg_valid && Reg(next=useScoreboard(_._1.cond(mem_ctrl)) || mem_ctrl.div || mem_ctrl.sqrt)
|
io.sboard_set := wb_reg_valid && Reg(next=useScoreboard(_._1.cond(mem_ctrl)) || mem_ctrl.div || mem_ctrl.sqrt)
|
||||||
io.ctrl.sboard_clr := divSqrt_wen || (wen(0) && useScoreboard(x => wsrc === UInt(x._2)))
|
io.sboard_clr := divSqrt_wen || (wen(0) && useScoreboard(x => wsrc === UInt(x._2)))
|
||||||
io.ctrl.sboard_clra := waddr
|
io.sboard_clra := waddr
|
||||||
// we don't currently support round-max-magnitude (rm=4)
|
// we don't currently support round-max-magnitude (rm=4)
|
||||||
io.ctrl.illegal_rm := ex_rm(2) && ex_ctrl.round
|
io.illegal_rm := ex_rm(2) && ex_ctrl.round
|
||||||
|
|
||||||
divSqrt_wdata := 0
|
divSqrt_wdata := 0
|
||||||
divSqrt_flags := 0
|
divSqrt_flags := 0
|
||||||
@ -516,7 +514,7 @@ class FPU extends Module
|
|||||||
|
|
||||||
def upconvert(x: UInt) = hardfloat.recodedFloatNToRecodedFloatM(x, Bits(0), 23, 9, 52, 12)._1
|
def upconvert(x: UInt) = hardfloat.recodedFloatNToRecodedFloatM(x, Bits(0), 23, 9, 52, 12)._1
|
||||||
val divSqrt_wb_hazard = wen.orR
|
val divSqrt_wb_hazard = wen.orR
|
||||||
divSqrt.io.inValid := mem_reg_valid && !divSqrt_wb_hazard && !divSqrt_in_flight && !io.ctrl.killm && (mem_ctrl.div || mem_ctrl.sqrt)
|
divSqrt.io.inValid := mem_reg_valid && !divSqrt_wb_hazard && !divSqrt_in_flight && !io.killm && (mem_ctrl.div || mem_ctrl.sqrt)
|
||||||
divSqrt.io.sqrtOp := mem_ctrl.sqrt
|
divSqrt.io.sqrtOp := mem_ctrl.sqrt
|
||||||
divSqrt.io.a := fpiu.io.as_double.in1
|
divSqrt.io.a := fpiu.io.as_double.in1
|
||||||
divSqrt.io.b := fpiu.io.as_double.in2
|
divSqrt.io.b := fpiu.io.as_double.in2
|
||||||
|
|||||||
@ -1,4 +1,4 @@
|
|||||||
// See LICENSE for license details.
|
// See LICENSE for license details
|
||||||
|
|
||||||
package rocket
|
package rocket
|
||||||
|
|
||||||
@ -6,50 +6,6 @@ import Chisel._
|
|||||||
import Instructions._
|
import Instructions._
|
||||||
import uncore.constants.MemoryOpConstants._
|
import uncore.constants.MemoryOpConstants._
|
||||||
import ALU._
|
import ALU._
|
||||||
import Util._
|
|
||||||
|
|
||||||
class CtrlDpathIO extends CoreBundle
|
|
||||||
{
|
|
||||||
// outputs to datapath
|
|
||||||
val sel_pc = UInt(OUTPUT, 3)
|
|
||||||
val killd = Bool(OUTPUT)
|
|
||||||
val killm = Bool(OUTPUT)
|
|
||||||
val ren = Vec.fill(2)(Bool(OUTPUT))
|
|
||||||
val ex_ctrl = new IntCtrlSigs().asOutput
|
|
||||||
val mem_ctrl = new IntCtrlSigs().asOutput
|
|
||||||
val csr_cmd = UInt(OUTPUT, CSR.SZ)
|
|
||||||
val ex_valid = Bool(OUTPUT)
|
|
||||||
val wb_wen = Bool(OUTPUT)
|
|
||||||
val bypass = Vec.fill(2)(Bool(OUTPUT))
|
|
||||||
val bypass_src = Vec.fill(2)(Bits(OUTPUT, SZ_BYP))
|
|
||||||
val ll_ready = Bool(OUTPUT)
|
|
||||||
// exception handling
|
|
||||||
val retire = Bool(OUTPUT)
|
|
||||||
val exception = Bool(OUTPUT)
|
|
||||||
val cause = UInt(OUTPUT, xLen)
|
|
||||||
// inputs from datapath
|
|
||||||
val inst = Bits(INPUT, 32)
|
|
||||||
val mem_br_taken = Bool(INPUT)
|
|
||||||
val mem_misprediction = Bool(INPUT)
|
|
||||||
val mem_npc_misaligned = Bool(INPUT)
|
|
||||||
val div_mul_rdy = Bool(INPUT)
|
|
||||||
val ll_wen = Bool(INPUT)
|
|
||||||
val ll_waddr = UInt(INPUT, 5)
|
|
||||||
val ex_waddr = UInt(INPUT, 5)
|
|
||||||
val mem_rs1_ra = Bool(INPUT)
|
|
||||||
val mem_waddr = UInt(INPUT, 5)
|
|
||||||
val wb_waddr = UInt(INPUT, 5)
|
|
||||||
val status = new MStatus().asInput
|
|
||||||
val fp_sboard_clr = Bool(INPUT)
|
|
||||||
val fp_sboard_clra = UInt(INPUT, 5)
|
|
||||||
// inputs from csr file
|
|
||||||
val csr_replay = Bool(INPUT)
|
|
||||||
val csr_stall = Bool(INPUT)
|
|
||||||
val csr_xcpt = Bool(INPUT)
|
|
||||||
val eret = Bool(INPUT)
|
|
||||||
val interrupt = Bool(INPUT)
|
|
||||||
val interrupt_cause = UInt(INPUT, xLen)
|
|
||||||
}
|
|
||||||
|
|
||||||
abstract trait DecodeConstants
|
abstract trait DecodeConstants
|
||||||
{
|
{
|
||||||
@ -343,343 +299,3 @@ object RoCCDecode extends DecodeConstants
|
|||||||
CUSTOM3_RD_RS1-> List(Y, N,Y,N,N,N,N,Y,A2_ZERO,A1_RS1, IMM_X, DW_XPR,FN_ADD, N,M_X, MT_X, N,N,N,N,N,Y,CSR.N,N,N,N),
|
CUSTOM3_RD_RS1-> List(Y, N,Y,N,N,N,N,Y,A2_ZERO,A1_RS1, IMM_X, DW_XPR,FN_ADD, N,M_X, MT_X, N,N,N,N,N,Y,CSR.N,N,N,N),
|
||||||
CUSTOM3_RD_RS1_RS2->List(Y, N,Y,N,N,N,Y,Y,A2_ZERO,A1_RS1, IMM_X, DW_XPR,FN_ADD, N,M_X, MT_X, N,N,N,N,N,Y,CSR.N,N,N,N))
|
CUSTOM3_RD_RS1_RS2->List(Y, N,Y,N,N,N,Y,Y,A2_ZERO,A1_RS1, IMM_X, DW_XPR,FN_ADD, N,M_X, MT_X, N,N,N,N,N,Y,CSR.N,N,N,N))
|
||||||
}
|
}
|
||||||
|
|
||||||
class Control extends CoreModule
|
|
||||||
{
|
|
||||||
val io = new Bundle {
|
|
||||||
val dpath = new CtrlDpathIO
|
|
||||||
val imem = new CPUFrontendIO
|
|
||||||
val dmem = new HellaCacheIO
|
|
||||||
val fpu = new CtrlFPUIO
|
|
||||||
val rocc = new RoCCInterface().flip
|
|
||||||
}
|
|
||||||
|
|
||||||
var decode_table = XDecode.table
|
|
||||||
if (!params(BuildFPU).isEmpty) decode_table ++= FDecode.table
|
|
||||||
if (!params(BuildFPU).isEmpty && params(FDivSqrt)) decode_table ++= FDivSqrtDecode.table
|
|
||||||
if (!params(BuildRoCC).isEmpty) decode_table ++= RoCCDecode.table
|
|
||||||
|
|
||||||
val id_ctrl = Wire(new IntCtrlSigs()).decode(io.dpath.inst, decode_table)
|
|
||||||
val ex_ctrl = Reg(new IntCtrlSigs)
|
|
||||||
val mem_ctrl = Reg(new IntCtrlSigs)
|
|
||||||
val wb_ctrl = Reg(new IntCtrlSigs)
|
|
||||||
|
|
||||||
val ex_reg_xcpt_interrupt = Reg(Bool())
|
|
||||||
val ex_reg_valid = Reg(Bool())
|
|
||||||
val ex_reg_btb_hit = Reg(Bool())
|
|
||||||
val ex_reg_btb_resp = Reg(io.imem.btb_resp.bits)
|
|
||||||
val ex_reg_xcpt = Reg(Bool())
|
|
||||||
val ex_reg_flush_pipe = Reg(Bool())
|
|
||||||
val ex_reg_load_use = Reg(Bool())
|
|
||||||
val ex_reg_cause = Reg(UInt())
|
|
||||||
|
|
||||||
val mem_reg_xcpt_interrupt = Reg(Bool())
|
|
||||||
val mem_reg_valid = Reg(Bool())
|
|
||||||
val mem_reg_btb_hit = Reg(Bool())
|
|
||||||
val mem_reg_btb_resp = Reg(io.imem.btb_resp.bits)
|
|
||||||
val mem_reg_xcpt = Reg(Bool())
|
|
||||||
val mem_reg_replay = Reg(Bool())
|
|
||||||
val mem_reg_flush_pipe = Reg(Bool())
|
|
||||||
val mem_reg_cause = Reg(UInt())
|
|
||||||
val mem_reg_slow_bypass = Reg(Bool())
|
|
||||||
|
|
||||||
val wb_reg_valid = Reg(Bool())
|
|
||||||
val wb_reg_xcpt = Reg(Bool())
|
|
||||||
val wb_reg_replay = Reg(Bool())
|
|
||||||
val wb_reg_cause = Reg(UInt())
|
|
||||||
val wb_reg_rocc_pending = Reg(init=Bool(false))
|
|
||||||
|
|
||||||
val take_pc_wb = Wire(Bool())
|
|
||||||
val mem_misprediction = io.dpath.mem_misprediction && mem_reg_valid && (mem_ctrl.branch || mem_ctrl.jalr || mem_ctrl.jal)
|
|
||||||
val want_take_pc_mem = mem_reg_valid && (mem_misprediction || mem_reg_flush_pipe)
|
|
||||||
val take_pc_mem = want_take_pc_mem && !io.dpath.mem_npc_misaligned
|
|
||||||
val take_pc_mem_wb = take_pc_wb || take_pc_mem
|
|
||||||
val take_pc = take_pc_mem_wb
|
|
||||||
val ctrl_killd = Wire(Bool())
|
|
||||||
val ctrl_killx = Wire(Bool())
|
|
||||||
val ctrl_killm = Wire(Bool())
|
|
||||||
|
|
||||||
val id_raddr3 = io.dpath.inst(31,27)
|
|
||||||
val id_raddr2 = io.dpath.inst(24,20)
|
|
||||||
val id_raddr1 = io.dpath.inst(19,15)
|
|
||||||
val id_waddr = io.dpath.inst(11,7)
|
|
||||||
val id_load_use = Wire(Bool())
|
|
||||||
val id_reg_fence = Reg(init=Bool(false))
|
|
||||||
|
|
||||||
val id_csr_en = id_ctrl.csr != CSR.N
|
|
||||||
val id_system_insn = id_ctrl.csr === CSR.I
|
|
||||||
val id_csr_ren = (id_ctrl.csr === CSR.S || id_ctrl.csr === CSR.C) && id_raddr1 === UInt(0)
|
|
||||||
val id_csr = Mux(id_csr_ren, CSR.R, id_ctrl.csr)
|
|
||||||
val id_csr_addr = io.dpath.inst(31,20)
|
|
||||||
// this is overly conservative
|
|
||||||
val safe_csrs = CSRs.sscratch :: CSRs.sepc :: CSRs.mscratch :: CSRs.mepc :: CSRs.mcause :: CSRs.mbadaddr :: Nil
|
|
||||||
val legal_csrs = collection.mutable.LinkedHashSet(CSRs.all:_*)
|
|
||||||
val id_csr_flush = id_system_insn || (id_csr_en && !id_csr_ren && !DecodeLogic(id_csr_addr, safe_csrs, legal_csrs -- safe_csrs))
|
|
||||||
|
|
||||||
val id_illegal_insn = !id_ctrl.legal ||
|
|
||||||
id_ctrl.fp && !io.dpath.status.fs.orR ||
|
|
||||||
id_ctrl.rocc && !io.dpath.status.xs.orR
|
|
||||||
// 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_ctrl.fence || id_ctrl.amo && id_amo_rl
|
|
||||||
val id_mem_busy = !io.dmem.ordered || io.dmem.req.valid
|
|
||||||
val id_rocc_busy = Bool(!params(BuildRoCC).isEmpty) &&
|
|
||||||
(io.rocc.busy || ex_reg_valid && ex_ctrl.rocc ||
|
|
||||||
mem_reg_valid && mem_ctrl.rocc || wb_reg_valid && wb_ctrl.rocc)
|
|
||||||
id_reg_fence := id_fence_next || id_reg_fence && id_mem_busy
|
|
||||||
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_en)
|
|
||||||
|
|
||||||
def checkExceptions(x: Seq[(Bool, UInt)]) =
|
|
||||||
(x.map(_._1).reduce(_||_), PriorityMux(x))
|
|
||||||
|
|
||||||
val (id_xcpt, id_cause) = checkExceptions(List(
|
|
||||||
(io.dpath.interrupt, io.dpath.interrupt_cause),
|
|
||||||
(io.imem.resp.bits.xcpt_if, UInt(Causes.fault_fetch)),
|
|
||||||
(id_illegal_insn, UInt(Causes.illegal_instruction))))
|
|
||||||
|
|
||||||
ex_reg_valid := !ctrl_killd
|
|
||||||
ex_reg_xcpt := !ctrl_killd && id_xcpt
|
|
||||||
ex_reg_xcpt_interrupt := io.dpath.interrupt && !take_pc && io.imem.resp.valid
|
|
||||||
when (id_xcpt) { ex_reg_cause := id_cause }
|
|
||||||
|
|
||||||
when (!ctrl_killd) {
|
|
||||||
ex_ctrl := id_ctrl
|
|
||||||
ex_ctrl.csr := id_csr
|
|
||||||
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_flush_pipe := id_ctrl.fence_i || id_csr_flush
|
|
||||||
ex_reg_load_use := id_load_use
|
|
||||||
ex_reg_xcpt := id_xcpt
|
|
||||||
}
|
|
||||||
|
|
||||||
// replay inst in ex stage
|
|
||||||
val wb_dcache_miss = wb_ctrl.mem && !io.dmem.resp.valid
|
|
||||||
val replay_ex_structural = ex_ctrl.mem && !io.dmem.req.ready ||
|
|
||||||
ex_ctrl.div && !io.dpath.div_mul_rdy
|
|
||||||
val replay_ex_load_use = wb_dcache_miss && ex_reg_load_use
|
|
||||||
val replay_ex = ex_reg_valid && (replay_ex_structural || replay_ex_load_use)
|
|
||||||
ctrl_killx := take_pc_mem_wb || replay_ex || !ex_reg_valid
|
|
||||||
// detect 2-cycle load-use delay for LB/LH/SC
|
|
||||||
val ex_slow_bypass = ex_ctrl.mem_cmd === M_XSC || Vec(MT_B, MT_BU, MT_H, MT_HU).contains(ex_ctrl.mem_type)
|
|
||||||
|
|
||||||
val (ex_xcpt, ex_cause) = checkExceptions(List(
|
|
||||||
(ex_reg_xcpt_interrupt || ex_reg_xcpt, ex_reg_cause),
|
|
||||||
(ex_ctrl.fp && io.fpu.illegal_rm, UInt(Causes.illegal_instruction))))
|
|
||||||
|
|
||||||
mem_reg_valid := !ctrl_killx
|
|
||||||
mem_reg_replay := !take_pc_mem_wb && replay_ex
|
|
||||||
mem_reg_xcpt := !ctrl_killx && ex_xcpt
|
|
||||||
mem_reg_xcpt_interrupt := !take_pc_mem_wb && ex_reg_xcpt_interrupt
|
|
||||||
when (ex_xcpt) { mem_reg_cause := ex_cause }
|
|
||||||
|
|
||||||
when (!ctrl_killx) {
|
|
||||||
mem_ctrl := ex_ctrl
|
|
||||||
mem_reg_btb_hit := ex_reg_btb_hit
|
|
||||||
when (ex_reg_btb_hit) { mem_reg_btb_resp := ex_reg_btb_resp }
|
|
||||||
mem_reg_flush_pipe := ex_reg_flush_pipe
|
|
||||||
mem_reg_slow_bypass := ex_slow_bypass
|
|
||||||
mem_reg_xcpt := ex_xcpt
|
|
||||||
}
|
|
||||||
|
|
||||||
val (mem_xcpt, mem_cause) = checkExceptions(List(
|
|
||||||
(mem_reg_xcpt_interrupt || mem_reg_xcpt, mem_reg_cause),
|
|
||||||
(want_take_pc_mem && io.dpath.mem_npc_misaligned, UInt(Causes.misaligned_fetch)),
|
|
||||||
(mem_reg_valid && mem_ctrl.mem && io.dmem.xcpt.ma.st, UInt(Causes.misaligned_store)),
|
|
||||||
(mem_reg_valid && mem_ctrl.mem && io.dmem.xcpt.ma.ld, UInt(Causes.misaligned_load)),
|
|
||||||
(mem_reg_valid && mem_ctrl.mem && io.dmem.xcpt.pf.st, UInt(Causes.fault_store)),
|
|
||||||
(mem_reg_valid && mem_ctrl.mem && io.dmem.xcpt.pf.ld, UInt(Causes.fault_load))))
|
|
||||||
|
|
||||||
val dcache_kill_mem = mem_reg_valid && mem_ctrl.wxd && io.dmem.replay_next.valid // structural hazard on writeback port
|
|
||||||
val fpu_kill_mem = mem_reg_valid && mem_ctrl.fp && io.fpu.nack_mem
|
|
||||||
val replay_mem = dcache_kill_mem || mem_reg_replay || fpu_kill_mem
|
|
||||||
val killm_common = dcache_kill_mem || take_pc_wb || mem_reg_xcpt || !mem_reg_valid
|
|
||||||
ctrl_killm := killm_common || mem_xcpt || fpu_kill_mem
|
|
||||||
|
|
||||||
wb_reg_valid := !ctrl_killm
|
|
||||||
when (!ctrl_killm) { wb_ctrl := mem_ctrl }
|
|
||||||
wb_reg_replay := replay_mem && !take_pc_wb
|
|
||||||
wb_reg_xcpt := mem_xcpt && !take_pc_wb
|
|
||||||
when (mem_xcpt) { wb_reg_cause := mem_cause }
|
|
||||||
|
|
||||||
val wb_set_sboard = wb_ctrl.div || wb_dcache_miss || wb_ctrl.rocc
|
|
||||||
val replay_wb_common =
|
|
||||||
io.dmem.resp.bits.nack || wb_reg_replay || io.dpath.csr_replay
|
|
||||||
val wb_rocc_val = wb_reg_valid && wb_ctrl.rocc && !replay_wb_common
|
|
||||||
val replay_wb = replay_wb_common || wb_reg_valid && wb_ctrl.rocc && !io.rocc.cmd.ready
|
|
||||||
|
|
||||||
when (wb_rocc_val) { wb_reg_rocc_pending := !io.rocc.cmd.ready }
|
|
||||||
when (wb_reg_xcpt) { wb_reg_rocc_pending := Bool(false) }
|
|
||||||
|
|
||||||
class Scoreboard(n: Int)
|
|
||||||
{
|
|
||||||
def set(en: Bool, addr: UInt): Unit = update(en, _next | mask(en, addr))
|
|
||||||
def clear(en: Bool, addr: UInt): Unit = update(en, _next & ~mask(en, addr))
|
|
||||||
def read(addr: UInt): Bool = r(addr)
|
|
||||||
def readBypassed(addr: UInt): Bool = _next(addr)
|
|
||||||
|
|
||||||
private val r = Reg(init=Bits(0, n))
|
|
||||||
private var _next = r
|
|
||||||
private var ens = Bool(false)
|
|
||||||
private def mask(en: Bool, addr: UInt) = Mux(en, UInt(1) << addr, UInt(0))
|
|
||||||
private def update(en: Bool, update: UInt) = {
|
|
||||||
_next = update
|
|
||||||
ens = ens || en
|
|
||||||
when (ens) { r := _next }
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
val sboard = new Scoreboard(32)
|
|
||||||
sboard.clear(io.dpath.ll_wen, io.dpath.ll_waddr)
|
|
||||||
|
|
||||||
val id_stall_fpu = if (!params(BuildFPU).isEmpty) {
|
|
||||||
val fp_sboard = new Scoreboard(32)
|
|
||||||
fp_sboard.set((wb_dcache_miss && wb_ctrl.wfd || io.fpu.sboard_set) && io.dpath.retire, io.dpath.wb_waddr)
|
|
||||||
fp_sboard.clear(io.dpath.fp_sboard_clr, io.dpath.fp_sboard_clra)
|
|
||||||
fp_sboard.clear(io.fpu.sboard_clr, io.fpu.sboard_clra)
|
|
||||||
|
|
||||||
id_csr_en && !io.fpu.fcsr_rdy ||
|
|
||||||
io.fpu.dec.ren1 && fp_sboard.read(id_raddr1) ||
|
|
||||||
io.fpu.dec.ren2 && fp_sboard.read(id_raddr2) ||
|
|
||||||
io.fpu.dec.ren3 && fp_sboard.read(id_raddr3) ||
|
|
||||||
io.fpu.dec.wen && fp_sboard.read(id_waddr)
|
|
||||||
} else Bool(false)
|
|
||||||
|
|
||||||
// write CAUSE CSR on an exception
|
|
||||||
io.dpath.exception := wb_reg_xcpt
|
|
||||||
io.dpath.cause := wb_reg_cause
|
|
||||||
val wb_xcpt = wb_reg_xcpt || io.dpath.csr_xcpt
|
|
||||||
|
|
||||||
// control transfer from ex/wb
|
|
||||||
take_pc_wb := replay_wb || wb_xcpt || io.dpath.eret
|
|
||||||
|
|
||||||
io.dpath.sel_pc :=
|
|
||||||
Mux(wb_xcpt || io.dpath.eret, PC_CSR, // exception or [m|s]ret
|
|
||||||
Mux(replay_wb, PC_WB, // replay
|
|
||||||
PC_MEM))
|
|
||||||
|
|
||||||
io.imem.btb_update.valid := mem_reg_valid && !io.dpath.mem_npc_misaligned && io.dpath.mem_misprediction && ((mem_ctrl.branch && io.dpath.mem_br_taken) || mem_ctrl.jalr || mem_ctrl.jal) && !take_pc_wb
|
|
||||||
io.imem.btb_update.bits.prediction.valid := mem_reg_btb_hit
|
|
||||||
io.imem.btb_update.bits.prediction.bits := mem_reg_btb_resp
|
|
||||||
io.imem.btb_update.bits.isJump := mem_ctrl.jal || mem_ctrl.jalr
|
|
||||||
io.imem.btb_update.bits.isReturn := mem_ctrl.jalr && io.dpath.mem_rs1_ra
|
|
||||||
|
|
||||||
io.imem.bht_update.valid := mem_reg_valid && mem_ctrl.branch && !take_pc_wb
|
|
||||||
io.imem.bht_update.bits.taken := io.dpath.mem_br_taken
|
|
||||||
io.imem.bht_update.bits.mispredict := io.dpath.mem_misprediction
|
|
||||||
io.imem.bht_update.bits.prediction.valid := mem_reg_btb_hit
|
|
||||||
io.imem.bht_update.bits.prediction.bits := mem_reg_btb_resp
|
|
||||||
|
|
||||||
io.imem.ras_update.valid := io.imem.btb_update.bits.isJump && !io.dpath.mem_npc_misaligned && !take_pc_wb
|
|
||||||
io.imem.ras_update.bits.isCall := mem_ctrl.wxd && io.dpath.mem_waddr(0)
|
|
||||||
io.imem.ras_update.bits.isReturn := mem_ctrl.jalr && io.dpath.mem_rs1_ra
|
|
||||||
io.imem.ras_update.bits.prediction.valid := mem_reg_btb_hit
|
|
||||||
io.imem.ras_update.bits.prediction.bits := mem_reg_btb_resp
|
|
||||||
|
|
||||||
io.imem.req.valid := take_pc
|
|
||||||
|
|
||||||
val bypassDst = Array(id_raddr1, id_raddr2)
|
|
||||||
val bypassSrc = Array.fill(NBYP)((Bool(true), UInt(0)))
|
|
||||||
bypassSrc(BYP_EX) = (ex_reg_valid && ex_ctrl.wxd, io.dpath.ex_waddr)
|
|
||||||
bypassSrc(BYP_MEM) = (mem_reg_valid && mem_ctrl.wxd && !mem_ctrl.mem, io.dpath.mem_waddr)
|
|
||||||
bypassSrc(BYP_DC) = (mem_reg_valid && mem_ctrl.wxd, io.dpath.mem_waddr)
|
|
||||||
|
|
||||||
val doBypass = bypassDst.map(d => bypassSrc.map(s => s._1 && s._2 === d))
|
|
||||||
for (i <- 0 until io.dpath.bypass.size) {
|
|
||||||
io.dpath.bypass(i) := doBypass(i).reduce(_||_)
|
|
||||||
io.dpath.bypass_src(i) := PriorityEncoder(doBypass(i))
|
|
||||||
}
|
|
||||||
|
|
||||||
// stall for RAW/WAW hazards on CSRs, loads, AMOs, and mul/div in execute stage.
|
|
||||||
val id_renx1_not0 = id_ctrl.rxs1 && id_raddr1 != UInt(0)
|
|
||||||
val id_renx2_not0 = id_ctrl.rxs2 && id_raddr2 != UInt(0)
|
|
||||||
val id_wen_not0 = id_ctrl.wxd && id_waddr != UInt(0)
|
|
||||||
val ex_cannot_bypass = ex_ctrl.csr != CSR.N || ex_ctrl.jalr || ex_ctrl.mem || ex_ctrl.div || ex_ctrl.fp || ex_ctrl.rocc
|
|
||||||
val data_hazard_ex = ex_ctrl.wxd &&
|
|
||||||
(id_renx1_not0 && id_raddr1 === io.dpath.ex_waddr ||
|
|
||||||
id_renx2_not0 && id_raddr2 === io.dpath.ex_waddr ||
|
|
||||||
id_wen_not0 && id_waddr === io.dpath.ex_waddr)
|
|
||||||
val fp_data_hazard_ex = ex_ctrl.wfd &&
|
|
||||||
(io.fpu.dec.ren1 && id_raddr1 === io.dpath.ex_waddr ||
|
|
||||||
io.fpu.dec.ren2 && id_raddr2 === io.dpath.ex_waddr ||
|
|
||||||
io.fpu.dec.ren3 && id_raddr3 === io.dpath.ex_waddr ||
|
|
||||||
io.fpu.dec.wen && id_waddr === io.dpath.ex_waddr)
|
|
||||||
val id_ex_hazard = ex_reg_valid && (data_hazard_ex && ex_cannot_bypass || fp_data_hazard_ex)
|
|
||||||
|
|
||||||
// stall for RAW/WAW hazards on CSRs, LB/LH, and mul/div in memory stage.
|
|
||||||
val mem_mem_cmd_bh =
|
|
||||||
if (params(FastLoadWord)) Bool(!params(FastLoadByte)) && mem_reg_slow_bypass
|
|
||||||
else Bool(true)
|
|
||||||
val mem_cannot_bypass = mem_ctrl.csr != CSR.N || mem_ctrl.mem && mem_mem_cmd_bh || mem_ctrl.div || mem_ctrl.fp || mem_ctrl.rocc
|
|
||||||
val data_hazard_mem = mem_ctrl.wxd &&
|
|
||||||
(id_renx1_not0 && id_raddr1 === io.dpath.mem_waddr ||
|
|
||||||
id_renx2_not0 && id_raddr2 === io.dpath.mem_waddr ||
|
|
||||||
id_wen_not0 && id_waddr === io.dpath.mem_waddr)
|
|
||||||
val fp_data_hazard_mem = mem_ctrl.wfd &&
|
|
||||||
(io.fpu.dec.ren1 && id_raddr1 === io.dpath.mem_waddr ||
|
|
||||||
io.fpu.dec.ren2 && id_raddr2 === io.dpath.mem_waddr ||
|
|
||||||
io.fpu.dec.ren3 && id_raddr3 === io.dpath.mem_waddr ||
|
|
||||||
io.fpu.dec.wen && id_waddr === io.dpath.mem_waddr)
|
|
||||||
val id_mem_hazard = mem_reg_valid && (data_hazard_mem && mem_cannot_bypass || fp_data_hazard_mem)
|
|
||||||
id_load_use := mem_reg_valid && data_hazard_mem && mem_ctrl.mem
|
|
||||||
|
|
||||||
// stall for RAW/WAW hazards on load/AMO misses and mul/div in writeback.
|
|
||||||
val data_hazard_wb = wb_ctrl.wxd &&
|
|
||||||
(id_renx1_not0 && id_raddr1 === io.dpath.wb_waddr ||
|
|
||||||
id_renx2_not0 && id_raddr2 === io.dpath.wb_waddr ||
|
|
||||||
id_wen_not0 && id_waddr === io.dpath.wb_waddr)
|
|
||||||
val fp_data_hazard_wb = wb_ctrl.wfd &&
|
|
||||||
(io.fpu.dec.ren1 && id_raddr1 === io.dpath.wb_waddr ||
|
|
||||||
io.fpu.dec.ren2 && id_raddr2 === io.dpath.wb_waddr ||
|
|
||||||
io.fpu.dec.ren3 && id_raddr3 === io.dpath.wb_waddr ||
|
|
||||||
io.fpu.dec.wen && id_waddr === io.dpath.wb_waddr)
|
|
||||||
val id_wb_hazard = wb_reg_valid && (data_hazard_wb && wb_set_sboard || fp_data_hazard_wb)
|
|
||||||
|
|
||||||
val id_sboard_hazard =
|
|
||||||
(id_renx1_not0 && sboard.readBypassed(id_raddr1) ||
|
|
||||||
id_renx2_not0 && sboard.readBypassed(id_raddr2) ||
|
|
||||||
id_wen_not0 && sboard.readBypassed(id_waddr))
|
|
||||||
|
|
||||||
sboard.set(wb_set_sboard && io.dpath.wb_wen, io.dpath.wb_waddr)
|
|
||||||
|
|
||||||
val ctrl_stalld =
|
|
||||||
id_ex_hazard || id_mem_hazard || id_wb_hazard || id_sboard_hazard ||
|
|
||||||
id_ctrl.fp && id_stall_fpu ||
|
|
||||||
id_ctrl.mem && !io.dmem.req.ready ||
|
|
||||||
Bool(!params(BuildRoCC).isEmpty) && wb_reg_rocc_pending && id_ctrl.rocc && !io.rocc.cmd.ready ||
|
|
||||||
id_do_fence ||
|
|
||||||
io.dpath.csr_stall
|
|
||||||
val ctrl_draind = io.dpath.interrupt
|
|
||||||
ctrl_killd := !io.imem.resp.valid || take_pc || ctrl_stalld || ctrl_draind
|
|
||||||
|
|
||||||
io.dpath.killd := take_pc || ctrl_stalld && !ctrl_draind
|
|
||||||
io.imem.resp.ready := !ctrl_stalld || ctrl_draind
|
|
||||||
io.imem.invalidate := wb_reg_valid && wb_ctrl.fence_i
|
|
||||||
|
|
||||||
io.dpath.ren(1) := id_ctrl.rxs2
|
|
||||||
io.dpath.ren(0) := id_ctrl.rxs1
|
|
||||||
io.dpath.ex_ctrl := ex_ctrl
|
|
||||||
io.dpath.mem_ctrl := mem_ctrl
|
|
||||||
io.dpath.ex_valid := ex_reg_valid
|
|
||||||
io.dpath.ll_ready := !(wb_reg_valid && wb_ctrl.wxd)
|
|
||||||
io.dpath.retire := wb_reg_valid && !replay_wb && !io.dpath.csr_xcpt
|
|
||||||
io.dpath.wb_wen := io.dpath.retire && wb_ctrl.wxd
|
|
||||||
io.dpath.csr_cmd := Mux(wb_reg_valid, wb_ctrl.csr, CSR.N)
|
|
||||||
io.dpath.killm := killm_common
|
|
||||||
|
|
||||||
io.fpu.valid := !ctrl_killd && id_ctrl.fp
|
|
||||||
io.fpu.killx := ctrl_killx
|
|
||||||
io.fpu.killm := killm_common
|
|
||||||
|
|
||||||
io.dmem.req.valid := ex_reg_valid && ex_ctrl.mem
|
|
||||||
io.dmem.req.bits.kill := killm_common || mem_xcpt
|
|
||||||
io.dmem.req.bits.cmd := ex_ctrl.mem_cmd
|
|
||||||
io.dmem.req.bits.typ := ex_ctrl.mem_type
|
|
||||||
io.dmem.req.bits.phys := Bool(false)
|
|
||||||
io.dmem.invalidate_lr := wb_xcpt
|
|
||||||
|
|
||||||
io.rocc.cmd.valid := wb_rocc_val
|
|
||||||
io.rocc.exception := wb_xcpt && io.dpath.status.xs.orR
|
|
||||||
io.rocc.s := io.dpath.status.prv.orR // should we just pass all of mstatus?
|
|
||||||
}
|
|
||||||
599
rocket/src/main/scala/rocket.scala
Normal file
599
rocket/src/main/scala/rocket.scala
Normal file
@ -0,0 +1,599 @@
|
|||||||
|
// See LICENSE for license details.
|
||||||
|
|
||||||
|
package rocket
|
||||||
|
|
||||||
|
import Chisel._
|
||||||
|
import uncore._
|
||||||
|
import Util._
|
||||||
|
|
||||||
|
case object BuildFPU extends Field[Option[() => FPU]]
|
||||||
|
case object FDivSqrt extends Field[Boolean]
|
||||||
|
case object XLen extends Field[Int]
|
||||||
|
case object NMultXpr extends Field[Int]
|
||||||
|
case object FetchWidth extends Field[Int]
|
||||||
|
case object RetireWidth extends Field[Int]
|
||||||
|
case object UseVM extends Field[Boolean]
|
||||||
|
case object FastLoadWord extends Field[Boolean]
|
||||||
|
case object FastLoadByte extends Field[Boolean]
|
||||||
|
case object FastMulDiv extends Field[Boolean]
|
||||||
|
case object CoreInstBits extends Field[Int]
|
||||||
|
case object CoreDataBits extends Field[Int]
|
||||||
|
case object CoreDCacheReqTagBits extends Field[Int]
|
||||||
|
case object NCustomMRWCSRs extends Field[Int]
|
||||||
|
|
||||||
|
abstract trait CoreParameters extends UsesParameters {
|
||||||
|
val xLen = params(XLen)
|
||||||
|
val paddrBits = params(PAddrBits)
|
||||||
|
val vaddrBits = params(VAddrBits)
|
||||||
|
val pgIdxBits = params(PgIdxBits)
|
||||||
|
val ppnBits = params(PPNBits)
|
||||||
|
val vpnBits = params(VPNBits)
|
||||||
|
val pgLevels = params(PgLevels)
|
||||||
|
val pgLevelBits = params(PgLevelBits)
|
||||||
|
val asIdBits = params(ASIdBits)
|
||||||
|
|
||||||
|
val retireWidth = params(RetireWidth)
|
||||||
|
val coreFetchWidth = params(FetchWidth)
|
||||||
|
val coreInstBits = params(CoreInstBits)
|
||||||
|
val coreInstBytes = coreInstBits/8
|
||||||
|
val coreDataBits = xLen
|
||||||
|
val coreDataBytes = coreDataBits/8
|
||||||
|
val coreDCacheReqTagBits = params(CoreDCacheReqTagBits)
|
||||||
|
val coreMaxAddrBits = math.max(ppnBits,vpnBits+1) + pgIdxBits
|
||||||
|
val vaddrBitsExtended = vaddrBits + (vaddrBits < xLen).toInt
|
||||||
|
|
||||||
|
if(params(FastLoadByte)) require(params(FastLoadWord))
|
||||||
|
}
|
||||||
|
|
||||||
|
abstract trait RocketCoreParameters extends CoreParameters
|
||||||
|
{
|
||||||
|
require(params(FetchWidth) == 1) // for now...
|
||||||
|
require(params(RetireWidth) == 1) // for now...
|
||||||
|
}
|
||||||
|
|
||||||
|
abstract class CoreBundle extends Bundle with CoreParameters
|
||||||
|
abstract class CoreModule extends Module with CoreParameters
|
||||||
|
|
||||||
|
class Rocket extends CoreModule
|
||||||
|
{
|
||||||
|
val io = new Bundle {
|
||||||
|
val host = new HTIFIO
|
||||||
|
val imem = new CPUFrontendIO
|
||||||
|
val dmem = new HellaCacheIO
|
||||||
|
val ptw = new DatapathPTWIO().flip
|
||||||
|
val fpu = new FPUIO().flip
|
||||||
|
val rocc = new RoCCInterface().flip
|
||||||
|
}
|
||||||
|
|
||||||
|
var decode_table = XDecode.table
|
||||||
|
if (!params(BuildFPU).isEmpty) decode_table ++= FDecode.table
|
||||||
|
if (!params(BuildFPU).isEmpty && params(FDivSqrt)) decode_table ++= FDivSqrtDecode.table
|
||||||
|
if (!params(BuildRoCC).isEmpty) decode_table ++= RoCCDecode.table
|
||||||
|
|
||||||
|
val ex_ctrl = Reg(new IntCtrlSigs)
|
||||||
|
val mem_ctrl = Reg(new IntCtrlSigs)
|
||||||
|
val wb_ctrl = Reg(new IntCtrlSigs)
|
||||||
|
|
||||||
|
val ex_reg_xcpt_interrupt = Reg(Bool())
|
||||||
|
val ex_reg_valid = Reg(Bool())
|
||||||
|
val ex_reg_btb_hit = Reg(Bool())
|
||||||
|
val ex_reg_btb_resp = Reg(io.imem.btb_resp.bits)
|
||||||
|
val ex_reg_xcpt = Reg(Bool())
|
||||||
|
val ex_reg_flush_pipe = Reg(Bool())
|
||||||
|
val ex_reg_load_use = Reg(Bool())
|
||||||
|
val ex_reg_cause = Reg(UInt())
|
||||||
|
val ex_reg_pc = Reg(UInt())
|
||||||
|
val ex_reg_inst = Reg(Bits())
|
||||||
|
|
||||||
|
val mem_reg_xcpt_interrupt = Reg(Bool())
|
||||||
|
val mem_reg_valid = Reg(Bool())
|
||||||
|
val mem_reg_btb_hit = Reg(Bool())
|
||||||
|
val mem_reg_btb_resp = Reg(io.imem.btb_resp.bits)
|
||||||
|
val mem_reg_xcpt = Reg(Bool())
|
||||||
|
val mem_reg_replay = Reg(Bool())
|
||||||
|
val mem_reg_flush_pipe = Reg(Bool())
|
||||||
|
val mem_reg_cause = Reg(UInt())
|
||||||
|
val mem_reg_slow_bypass = Reg(Bool())
|
||||||
|
val mem_reg_pc = Reg(UInt())
|
||||||
|
val mem_reg_inst = Reg(Bits())
|
||||||
|
val mem_reg_wdata = Reg(Bits())
|
||||||
|
val mem_reg_rs2 = Reg(Bits())
|
||||||
|
val take_pc_mem = Wire(Bool())
|
||||||
|
|
||||||
|
val wb_reg_valid = Reg(Bool())
|
||||||
|
val wb_reg_xcpt = Reg(Bool())
|
||||||
|
val wb_reg_replay = Reg(Bool())
|
||||||
|
val wb_reg_cause = Reg(UInt())
|
||||||
|
val wb_reg_rocc_pending = Reg(init=Bool(false))
|
||||||
|
val wb_reg_pc = Reg(UInt())
|
||||||
|
val wb_reg_inst = Reg(Bits())
|
||||||
|
val wb_reg_wdata = Reg(Bits())
|
||||||
|
val wb_reg_rs2 = Reg(Bits())
|
||||||
|
val take_pc_wb = Wire(Bool())
|
||||||
|
|
||||||
|
val take_pc_mem_wb = take_pc_wb || take_pc_mem
|
||||||
|
val take_pc = take_pc_mem_wb
|
||||||
|
|
||||||
|
// decode stage
|
||||||
|
val id_pc = io.imem.resp.bits.pc
|
||||||
|
val id_inst = io.imem.resp.bits.data(0).toBits; require(params(FetchWidth) == 1)
|
||||||
|
val id_ctrl = Wire(new IntCtrlSigs()).decode(id_inst, decode_table)
|
||||||
|
val id_raddr3 = id_inst(31,27)
|
||||||
|
val id_raddr2 = id_inst(24,20)
|
||||||
|
val id_raddr1 = id_inst(19,15)
|
||||||
|
val id_waddr = id_inst(11,7)
|
||||||
|
val id_load_use = Wire(Bool())
|
||||||
|
val id_reg_fence = Reg(init=Bool(false))
|
||||||
|
val id_ren = IndexedSeq(id_ctrl.rxs1, id_ctrl.rxs2)
|
||||||
|
val id_raddr = IndexedSeq(id_raddr1, id_raddr2)
|
||||||
|
val rf = new RegFile
|
||||||
|
val id_rs = id_raddr.map(rf.read _)
|
||||||
|
val ctrl_killd = Wire(Bool())
|
||||||
|
|
||||||
|
val csr = Module(new CSRFile)
|
||||||
|
val id_csr_en = id_ctrl.csr != CSR.N
|
||||||
|
val id_system_insn = id_ctrl.csr === CSR.I
|
||||||
|
val id_csr_ren = (id_ctrl.csr === CSR.S || id_ctrl.csr === CSR.C) && id_raddr1 === UInt(0)
|
||||||
|
val id_csr = Mux(id_csr_ren, CSR.R, id_ctrl.csr)
|
||||||
|
val id_csr_addr = id_inst(31,20)
|
||||||
|
// this is overly conservative
|
||||||
|
val safe_csrs = CSRs.sscratch :: CSRs.sepc :: CSRs.mscratch :: CSRs.mepc :: CSRs.mcause :: CSRs.mbadaddr :: Nil
|
||||||
|
val legal_csrs = collection.mutable.LinkedHashSet(CSRs.all:_*)
|
||||||
|
val id_csr_flush = id_system_insn || (id_csr_en && !id_csr_ren && !DecodeLogic(id_csr_addr, safe_csrs, legal_csrs -- safe_csrs))
|
||||||
|
|
||||||
|
val id_illegal_insn = !id_ctrl.legal ||
|
||||||
|
id_ctrl.fp && !csr.io.status.fs.orR ||
|
||||||
|
id_ctrl.rocc && !csr.io.status.xs.orR
|
||||||
|
// stall decode for fences (now, for AMO.aq; later, for AMO.rl and FENCE)
|
||||||
|
val id_amo_aq = id_inst(26)
|
||||||
|
val id_amo_rl = id_inst(25)
|
||||||
|
val id_fence_next = id_ctrl.fence || id_ctrl.amo && id_amo_rl
|
||||||
|
val id_mem_busy = !io.dmem.ordered || io.dmem.req.valid
|
||||||
|
val id_rocc_busy = Bool(!params(BuildRoCC).isEmpty) &&
|
||||||
|
(io.rocc.busy || ex_reg_valid && ex_ctrl.rocc ||
|
||||||
|
mem_reg_valid && mem_ctrl.rocc || wb_reg_valid && wb_ctrl.rocc)
|
||||||
|
id_reg_fence := id_fence_next || id_reg_fence && id_mem_busy
|
||||||
|
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_en)
|
||||||
|
|
||||||
|
val (id_xcpt, id_cause) = checkExceptions(List(
|
||||||
|
(csr.io.interrupt, csr.io.interrupt_cause),
|
||||||
|
(io.imem.resp.bits.xcpt_if, UInt(Causes.fault_fetch)),
|
||||||
|
(id_illegal_insn, UInt(Causes.illegal_instruction))))
|
||||||
|
|
||||||
|
val dcache_bypass_data =
|
||||||
|
if(params(FastLoadByte)) io.dmem.resp.bits.data_subword
|
||||||
|
else if(params(FastLoadWord)) io.dmem.resp.bits.data
|
||||||
|
else wb_reg_wdata
|
||||||
|
|
||||||
|
// detect bypass opportunities
|
||||||
|
val ex_waddr = ex_reg_inst(11,7)
|
||||||
|
val mem_waddr = mem_reg_inst(11,7)
|
||||||
|
val wb_waddr = wb_reg_inst(11,7)
|
||||||
|
val bypass_sources = IndexedSeq(
|
||||||
|
(Bool(true), UInt(0), UInt(0)), // treat reading x0 as a bypass
|
||||||
|
(ex_reg_valid && ex_ctrl.wxd, ex_waddr, mem_reg_wdata),
|
||||||
|
(mem_reg_valid && mem_ctrl.wxd && !mem_ctrl.mem, mem_waddr, wb_reg_wdata),
|
||||||
|
(mem_reg_valid && mem_ctrl.wxd, mem_waddr, dcache_bypass_data))
|
||||||
|
val id_bypass_src = id_raddr.map(raddr => bypass_sources.map(s => s._1 && s._2 === raddr))
|
||||||
|
|
||||||
|
// execute stage
|
||||||
|
val bypass_mux = Vec(bypass_sources.map(_._3))
|
||||||
|
val ex_reg_rs_bypass = Reg(Vec.fill(id_raddr.size)(Bool()))
|
||||||
|
val ex_reg_rs_lsb = Reg(Vec.fill(id_raddr.size)(Bits()))
|
||||||
|
val ex_reg_rs_msb = Reg(Vec.fill(id_raddr.size)(Bits()))
|
||||||
|
val ex_rs = for (i <- 0 until id_raddr.size)
|
||||||
|
yield Mux(ex_reg_rs_bypass(i), bypass_mux(ex_reg_rs_lsb(i)), Cat(ex_reg_rs_msb(i), ex_reg_rs_lsb(i)))
|
||||||
|
val ex_imm = imm(ex_ctrl.sel_imm, ex_reg_inst)
|
||||||
|
val ex_op1 = MuxLookup(ex_ctrl.sel_alu1, SInt(0), Seq(
|
||||||
|
A1_RS1 -> ex_rs(0).toSInt,
|
||||||
|
A1_PC -> ex_reg_pc.toSInt))
|
||||||
|
val ex_op2 = MuxLookup(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_ctrl.alu_dw
|
||||||
|
alu.io.fn := ex_ctrl.alu_fn
|
||||||
|
alu.io.in2 := ex_op2.toUInt
|
||||||
|
alu.io.in1 := ex_op1
|
||||||
|
|
||||||
|
// multiplier and divider
|
||||||
|
val div = Module(new MulDiv(mulUnroll = if(params(FastMulDiv)) 8 else 1,
|
||||||
|
earlyOut = params(FastMulDiv)))
|
||||||
|
div.io.req.valid := ex_reg_valid && ex_ctrl.div
|
||||||
|
div.io.req.bits.dw := ex_ctrl.alu_dw
|
||||||
|
div.io.req.bits.fn := 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 := ex_waddr
|
||||||
|
|
||||||
|
ex_reg_valid := !ctrl_killd
|
||||||
|
ex_reg_xcpt := !ctrl_killd && id_xcpt
|
||||||
|
ex_reg_xcpt_interrupt := csr.io.interrupt && !take_pc && io.imem.resp.valid
|
||||||
|
when (id_xcpt) { ex_reg_cause := id_cause }
|
||||||
|
|
||||||
|
when (!ctrl_killd) {
|
||||||
|
ex_ctrl := id_ctrl
|
||||||
|
ex_ctrl.csr := id_csr
|
||||||
|
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_flush_pipe := id_ctrl.fence_i || id_csr_flush
|
||||||
|
ex_reg_load_use := id_load_use
|
||||||
|
|
||||||
|
for (i <- 0 until id_raddr.size) {
|
||||||
|
val do_bypass = id_bypass_src(i).reduce(_||_)
|
||||||
|
val bypass_src = PriorityEncoder(id_bypass_src(i))
|
||||||
|
ex_reg_rs_bypass(i) := do_bypass
|
||||||
|
ex_reg_rs_lsb(i) := bypass_src
|
||||||
|
when (id_ren(i) && !do_bypass) {
|
||||||
|
ex_reg_rs_lsb(i) := id_rs(i)(bypass_src.getWidth-1,0)
|
||||||
|
ex_reg_rs_msb(i) := id_rs(i) >> bypass_src.getWidth
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
when (!ctrl_killd || csr.io.interrupt) {
|
||||||
|
ex_reg_inst := id_inst
|
||||||
|
ex_reg_pc := id_pc
|
||||||
|
}
|
||||||
|
|
||||||
|
// replay inst in ex stage?
|
||||||
|
val wb_dcache_miss = wb_ctrl.mem && !io.dmem.resp.valid
|
||||||
|
val replay_ex_structural = ex_ctrl.mem && !io.dmem.req.ready ||
|
||||||
|
ex_ctrl.div && !div.io.req.ready
|
||||||
|
val replay_ex_load_use = wb_dcache_miss && ex_reg_load_use
|
||||||
|
val replay_ex = ex_reg_valid && (replay_ex_structural || replay_ex_load_use)
|
||||||
|
val ctrl_killx = take_pc_mem_wb || replay_ex || !ex_reg_valid
|
||||||
|
// detect 2-cycle load-use delay for LB/LH/SC
|
||||||
|
val ex_slow_bypass = ex_ctrl.mem_cmd === M_XSC || Vec(MT_B, MT_BU, MT_H, MT_HU).contains(ex_ctrl.mem_type)
|
||||||
|
|
||||||
|
val (ex_xcpt, ex_cause) = checkExceptions(List(
|
||||||
|
(ex_reg_xcpt_interrupt || ex_reg_xcpt, ex_reg_cause),
|
||||||
|
(ex_ctrl.fp && io.fpu.illegal_rm, UInt(Causes.illegal_instruction))))
|
||||||
|
|
||||||
|
// memory stage
|
||||||
|
val mem_br_taken = mem_reg_wdata(0)
|
||||||
|
val mem_br_target = mem_reg_pc.toSInt +
|
||||||
|
Mux(mem_ctrl.branch && mem_br_taken, imm(IMM_SB, mem_reg_inst),
|
||||||
|
Mux(mem_ctrl.jal, imm(IMM_UJ, mem_reg_inst), SInt(4)))
|
||||||
|
val mem_int_wdata = Mux(mem_ctrl.jalr, mem_br_target, mem_reg_wdata.toSInt).toUInt
|
||||||
|
val mem_npc = (Mux(mem_ctrl.jalr, Cat(vaSign(mem_reg_wdata, mem_reg_wdata), mem_reg_wdata(vaddrBits-1,0)).toSInt, mem_br_target) & SInt(-2)).toUInt
|
||||||
|
val mem_wrong_npc = mem_npc != ex_reg_pc || !ex_reg_valid
|
||||||
|
val mem_npc_misaligned = mem_npc(1)
|
||||||
|
val mem_misprediction = mem_wrong_npc && mem_reg_valid && (mem_ctrl.branch || mem_ctrl.jalr || mem_ctrl.jal)
|
||||||
|
val want_take_pc_mem = mem_reg_valid && (mem_misprediction || mem_reg_flush_pipe)
|
||||||
|
take_pc_mem := want_take_pc_mem && !mem_npc_misaligned
|
||||||
|
|
||||||
|
mem_reg_valid := !ctrl_killx
|
||||||
|
mem_reg_replay := !take_pc_mem_wb && replay_ex
|
||||||
|
mem_reg_xcpt := !ctrl_killx && ex_xcpt
|
||||||
|
mem_reg_xcpt_interrupt := !take_pc_mem_wb && ex_reg_xcpt_interrupt
|
||||||
|
when (ex_xcpt) { mem_reg_cause := ex_cause }
|
||||||
|
|
||||||
|
when (ex_reg_valid || ex_reg_xcpt_interrupt) {
|
||||||
|
mem_ctrl := ex_ctrl
|
||||||
|
mem_reg_btb_hit := ex_reg_btb_hit
|
||||||
|
when (ex_reg_btb_hit) { mem_reg_btb_resp := ex_reg_btb_resp }
|
||||||
|
mem_reg_flush_pipe := ex_reg_flush_pipe
|
||||||
|
mem_reg_slow_bypass := ex_slow_bypass
|
||||||
|
|
||||||
|
mem_reg_inst := ex_reg_inst
|
||||||
|
mem_reg_pc := ex_reg_pc
|
||||||
|
mem_reg_wdata := alu.io.out
|
||||||
|
when (ex_ctrl.rxs2 && (ex_ctrl.mem || ex_ctrl.rocc)) {
|
||||||
|
mem_reg_rs2 := ex_rs(1)
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
val (mem_xcpt, mem_cause) = checkExceptions(List(
|
||||||
|
(mem_reg_xcpt_interrupt || mem_reg_xcpt, mem_reg_cause),
|
||||||
|
(want_take_pc_mem && mem_npc_misaligned, UInt(Causes.misaligned_fetch)),
|
||||||
|
(mem_reg_valid && mem_ctrl.mem && io.dmem.xcpt.ma.st, UInt(Causes.misaligned_store)),
|
||||||
|
(mem_reg_valid && mem_ctrl.mem && io.dmem.xcpt.ma.ld, UInt(Causes.misaligned_load)),
|
||||||
|
(mem_reg_valid && mem_ctrl.mem && io.dmem.xcpt.pf.st, UInt(Causes.fault_store)),
|
||||||
|
(mem_reg_valid && mem_ctrl.mem && io.dmem.xcpt.pf.ld, UInt(Causes.fault_load))))
|
||||||
|
|
||||||
|
val dcache_kill_mem = mem_reg_valid && mem_ctrl.wxd && io.dmem.replay_next.valid // structural hazard on writeback port
|
||||||
|
val fpu_kill_mem = mem_reg_valid && mem_ctrl.fp && io.fpu.nack_mem
|
||||||
|
val replay_mem = dcache_kill_mem || mem_reg_replay || fpu_kill_mem
|
||||||
|
val killm_common = dcache_kill_mem || take_pc_wb || mem_reg_xcpt || !mem_reg_valid
|
||||||
|
div.io.kill := killm_common && Reg(next = div.io.req.fire())
|
||||||
|
val ctrl_killm = killm_common || mem_xcpt || fpu_kill_mem
|
||||||
|
|
||||||
|
wb_reg_valid := !ctrl_killm
|
||||||
|
wb_reg_replay := replay_mem && !take_pc_wb
|
||||||
|
wb_reg_xcpt := mem_xcpt && !take_pc_wb
|
||||||
|
when (mem_xcpt) { wb_reg_cause := mem_cause }
|
||||||
|
when (mem_reg_valid || mem_reg_replay || mem_reg_xcpt_interrupt) {
|
||||||
|
wb_ctrl := mem_ctrl
|
||||||
|
wb_reg_wdata := Mux(mem_ctrl.fp && mem_ctrl.wxd, io.fpu.toint_data, mem_int_wdata)
|
||||||
|
when (mem_ctrl.rocc) {
|
||||||
|
wb_reg_rs2 := mem_reg_rs2
|
||||||
|
}
|
||||||
|
wb_reg_inst := mem_reg_inst
|
||||||
|
wb_reg_pc := mem_reg_pc
|
||||||
|
}
|
||||||
|
|
||||||
|
val wb_set_sboard = wb_ctrl.div || wb_dcache_miss || wb_ctrl.rocc
|
||||||
|
val replay_wb_common =
|
||||||
|
io.dmem.resp.bits.nack || wb_reg_replay || csr.io.csr_replay
|
||||||
|
val wb_rocc_val = wb_reg_valid && wb_ctrl.rocc && !replay_wb_common
|
||||||
|
val replay_wb = replay_wb_common || wb_reg_valid && wb_ctrl.rocc && !io.rocc.cmd.ready
|
||||||
|
|
||||||
|
when (wb_rocc_val) { wb_reg_rocc_pending := !io.rocc.cmd.ready }
|
||||||
|
when (wb_reg_xcpt) { wb_reg_rocc_pending := Bool(false) }
|
||||||
|
|
||||||
|
// writeback arbitration
|
||||||
|
val dmem_resp_xpu = !io.dmem.resp.bits.tag(0).toBool
|
||||||
|
val dmem_resp_fpu = io.dmem.resp.bits.tag(0).toBool
|
||||||
|
val dmem_resp_waddr = io.dmem.resp.bits.tag.toUInt >> UInt(1)
|
||||||
|
val dmem_resp_valid = io.dmem.resp.valid && io.dmem.resp.bits.has_data
|
||||||
|
val dmem_resp_replay = io.dmem.resp.bits.replay && io.dmem.resp.bits.has_data
|
||||||
|
|
||||||
|
div.io.resp.ready := !(wb_reg_valid && wb_ctrl.wxd)
|
||||||
|
val ll_wdata = Wire(init = div.io.resp.bits.data)
|
||||||
|
val ll_waddr = Wire(init = div.io.resp.bits.tag)
|
||||||
|
val ll_wen = Wire(init = div.io.resp.fire())
|
||||||
|
if (!params(BuildRoCC).isEmpty) {
|
||||||
|
io.rocc.resp.ready := !(wb_reg_valid && wb_ctrl.wxd)
|
||||||
|
when (io.rocc.resp.fire()) {
|
||||||
|
div.io.resp.ready := Bool(false)
|
||||||
|
ll_wdata := io.rocc.resp.bits.data
|
||||||
|
ll_waddr := io.rocc.resp.bits.rd
|
||||||
|
ll_wen := Bool(true)
|
||||||
|
}
|
||||||
|
}
|
||||||
|
when (dmem_resp_replay && dmem_resp_xpu) {
|
||||||
|
div.io.resp.ready := Bool(false)
|
||||||
|
if (!params(BuildRoCC).isEmpty)
|
||||||
|
io.rocc.resp.ready := Bool(false)
|
||||||
|
ll_waddr := dmem_resp_waddr
|
||||||
|
ll_wen := Bool(true)
|
||||||
|
}
|
||||||
|
|
||||||
|
val wb_valid = wb_reg_valid && !replay_wb && !csr.io.csr_xcpt
|
||||||
|
val wb_wen = wb_valid && wb_ctrl.wxd
|
||||||
|
val rf_wen = wb_wen || ll_wen
|
||||||
|
val rf_waddr = Mux(ll_wen, ll_waddr, wb_waddr)
|
||||||
|
val rf_wdata = Mux(dmem_resp_valid && dmem_resp_xpu, io.dmem.resp.bits.data_subword,
|
||||||
|
Mux(ll_wen, ll_wdata,
|
||||||
|
Mux(wb_ctrl.csr != CSR.N, csr.io.rw.rdata,
|
||||||
|
wb_reg_wdata)))
|
||||||
|
when (rf_wen) { rf.write(rf_waddr, rf_wdata) }
|
||||||
|
|
||||||
|
// hook up control/status regfile
|
||||||
|
csr.io.exception := wb_reg_xcpt
|
||||||
|
csr.io.cause := wb_reg_cause
|
||||||
|
csr.io.retire := wb_valid
|
||||||
|
csr.io.host <> io.host
|
||||||
|
io.fpu.fcsr_rm := csr.io.fcsr_rm
|
||||||
|
csr.io.fcsr_flags := io.fpu.fcsr_flags
|
||||||
|
csr.io.rocc <> io.rocc
|
||||||
|
csr.io.pc := wb_reg_pc
|
||||||
|
csr.io.uarch_counters.foreach(_ := Bool(false))
|
||||||
|
io.ptw.ptbr := csr.io.ptbr
|
||||||
|
io.ptw.invalidate := csr.io.fatc
|
||||||
|
io.ptw.status := csr.io.status
|
||||||
|
csr.io.rw.addr := wb_reg_inst(31,20)
|
||||||
|
csr.io.rw.cmd := Mux(wb_reg_valid, wb_ctrl.csr, CSR.N)
|
||||||
|
csr.io.rw.wdata := wb_reg_wdata
|
||||||
|
|
||||||
|
val sboard = new Scoreboard(32)
|
||||||
|
sboard.clear(ll_wen, ll_waddr)
|
||||||
|
|
||||||
|
// control transfer from ex/wb
|
||||||
|
val wb_xcpt = wb_reg_xcpt || csr.io.csr_xcpt
|
||||||
|
take_pc_wb := replay_wb || wb_xcpt || csr.io.eret
|
||||||
|
|
||||||
|
io.imem.req.bits.pc :=
|
||||||
|
Mux(wb_xcpt || csr.io.eret, csr.io.evec, // exception or [m|s]ret
|
||||||
|
Mux(replay_wb, wb_reg_pc, // replay
|
||||||
|
mem_npc)).toUInt // mispredicted branch
|
||||||
|
|
||||||
|
io.imem.btb_update.valid := mem_reg_valid && !mem_npc_misaligned && mem_wrong_npc && ((mem_ctrl.branch && mem_br_taken) || mem_ctrl.jalr || mem_ctrl.jal) && !take_pc_wb
|
||||||
|
io.imem.btb_update.bits.prediction.valid := mem_reg_btb_hit
|
||||||
|
io.imem.btb_update.bits.prediction.bits := mem_reg_btb_resp
|
||||||
|
io.imem.btb_update.bits.isJump := mem_ctrl.jal || mem_ctrl.jalr
|
||||||
|
io.imem.btb_update.bits.isReturn := mem_ctrl.jalr && mem_reg_inst(19,15) === Bits("b00??1")
|
||||||
|
|
||||||
|
io.imem.bht_update.valid := mem_reg_valid && mem_ctrl.branch && !take_pc_wb
|
||||||
|
io.imem.bht_update.bits.taken := mem_br_taken
|
||||||
|
io.imem.bht_update.bits.mispredict := mem_wrong_npc
|
||||||
|
io.imem.bht_update.bits.prediction.valid := mem_reg_btb_hit
|
||||||
|
io.imem.bht_update.bits.prediction.bits := mem_reg_btb_resp
|
||||||
|
|
||||||
|
io.imem.ras_update.valid := mem_reg_valid && io.imem.btb_update.bits.isJump && !mem_npc_misaligned && !take_pc_wb
|
||||||
|
io.imem.ras_update.bits.isCall := mem_ctrl.wxd && mem_waddr(0)
|
||||||
|
io.imem.ras_update.bits.isReturn := io.imem.btb_update.bits.isReturn
|
||||||
|
io.imem.ras_update.bits.prediction.valid := mem_reg_btb_hit
|
||||||
|
io.imem.ras_update.bits.prediction.bits := mem_reg_btb_resp
|
||||||
|
|
||||||
|
io.imem.req.valid := take_pc
|
||||||
|
io.imem.btb_update.bits.pc := mem_reg_pc
|
||||||
|
io.imem.btb_update.bits.target := io.imem.req.bits.pc
|
||||||
|
io.imem.btb_update.bits.br_pc := mem_reg_pc
|
||||||
|
io.imem.bht_update.bits.pc := mem_reg_pc
|
||||||
|
io.imem.ras_update.bits.returnAddr := mem_int_wdata
|
||||||
|
|
||||||
|
// stall for RAW/WAW hazards on CSRs, loads, AMOs, and mul/div in execute stage.
|
||||||
|
val id_renx1_not0 = id_ctrl.rxs1 && id_raddr1 != UInt(0)
|
||||||
|
val id_renx2_not0 = id_ctrl.rxs2 && id_raddr2 != UInt(0)
|
||||||
|
val id_wen_not0 = id_ctrl.wxd && id_waddr != UInt(0)
|
||||||
|
val ex_cannot_bypass = ex_ctrl.csr != CSR.N || ex_ctrl.jalr || ex_ctrl.mem || ex_ctrl.div || ex_ctrl.fp || ex_ctrl.rocc
|
||||||
|
val data_hazard_ex = ex_ctrl.wxd &&
|
||||||
|
(id_renx1_not0 && id_raddr1 === ex_waddr ||
|
||||||
|
id_renx2_not0 && id_raddr2 === ex_waddr ||
|
||||||
|
id_wen_not0 && id_waddr === ex_waddr)
|
||||||
|
val fp_data_hazard_ex = ex_ctrl.wfd &&
|
||||||
|
(io.fpu.dec.ren1 && id_raddr1 === ex_waddr ||
|
||||||
|
io.fpu.dec.ren2 && id_raddr2 === ex_waddr ||
|
||||||
|
io.fpu.dec.ren3 && id_raddr3 === ex_waddr ||
|
||||||
|
io.fpu.dec.wen && id_waddr === ex_waddr)
|
||||||
|
val id_ex_hazard = ex_reg_valid && (data_hazard_ex && ex_cannot_bypass || fp_data_hazard_ex)
|
||||||
|
|
||||||
|
// stall for RAW/WAW hazards on CSRs, LB/LH, and mul/div in memory stage.
|
||||||
|
val mem_mem_cmd_bh =
|
||||||
|
if (params(FastLoadWord)) Bool(!params(FastLoadByte)) && mem_reg_slow_bypass
|
||||||
|
else Bool(true)
|
||||||
|
val mem_cannot_bypass = mem_ctrl.csr != CSR.N || mem_ctrl.mem && mem_mem_cmd_bh || mem_ctrl.div || mem_ctrl.fp || mem_ctrl.rocc
|
||||||
|
val data_hazard_mem = mem_ctrl.wxd &&
|
||||||
|
(id_renx1_not0 && id_raddr1 === mem_waddr ||
|
||||||
|
id_renx2_not0 && id_raddr2 === mem_waddr ||
|
||||||
|
id_wen_not0 && id_waddr === mem_waddr)
|
||||||
|
val fp_data_hazard_mem = mem_ctrl.wfd &&
|
||||||
|
(io.fpu.dec.ren1 && id_raddr1 === mem_waddr ||
|
||||||
|
io.fpu.dec.ren2 && id_raddr2 === mem_waddr ||
|
||||||
|
io.fpu.dec.ren3 && id_raddr3 === mem_waddr ||
|
||||||
|
io.fpu.dec.wen && id_waddr === mem_waddr)
|
||||||
|
val id_mem_hazard = mem_reg_valid && (data_hazard_mem && mem_cannot_bypass || fp_data_hazard_mem)
|
||||||
|
id_load_use := mem_reg_valid && data_hazard_mem && mem_ctrl.mem
|
||||||
|
|
||||||
|
// stall for RAW/WAW hazards on load/AMO misses and mul/div in writeback.
|
||||||
|
val data_hazard_wb = wb_ctrl.wxd &&
|
||||||
|
(id_renx1_not0 && id_raddr1 === wb_waddr ||
|
||||||
|
id_renx2_not0 && id_raddr2 === wb_waddr ||
|
||||||
|
id_wen_not0 && id_waddr === wb_waddr)
|
||||||
|
val fp_data_hazard_wb = wb_ctrl.wfd &&
|
||||||
|
(io.fpu.dec.ren1 && id_raddr1 === wb_waddr ||
|
||||||
|
io.fpu.dec.ren2 && id_raddr2 === wb_waddr ||
|
||||||
|
io.fpu.dec.ren3 && id_raddr3 === wb_waddr ||
|
||||||
|
io.fpu.dec.wen && id_waddr === wb_waddr)
|
||||||
|
val id_wb_hazard = wb_reg_valid && (data_hazard_wb && wb_set_sboard || fp_data_hazard_wb)
|
||||||
|
|
||||||
|
val id_sboard_hazard =
|
||||||
|
(id_renx1_not0 && sboard.readBypassed(id_raddr1) ||
|
||||||
|
id_renx2_not0 && sboard.readBypassed(id_raddr2) ||
|
||||||
|
id_wen_not0 && sboard.readBypassed(id_waddr))
|
||||||
|
|
||||||
|
sboard.set(wb_set_sboard && wb_wen, wb_waddr)
|
||||||
|
|
||||||
|
val id_stall_fpu = if (!params(BuildFPU).isEmpty) {
|
||||||
|
val fp_sboard = new Scoreboard(32)
|
||||||
|
fp_sboard.set((wb_dcache_miss && wb_ctrl.wfd || io.fpu.sboard_set) && wb_valid, wb_waddr)
|
||||||
|
fp_sboard.clear(dmem_resp_replay && dmem_resp_fpu, dmem_resp_waddr)
|
||||||
|
fp_sboard.clear(io.fpu.sboard_clr, io.fpu.sboard_clra)
|
||||||
|
|
||||||
|
id_csr_en && !io.fpu.fcsr_rdy ||
|
||||||
|
io.fpu.dec.ren1 && fp_sboard.read(id_raddr1) ||
|
||||||
|
io.fpu.dec.ren2 && fp_sboard.read(id_raddr2) ||
|
||||||
|
io.fpu.dec.ren3 && fp_sboard.read(id_raddr3) ||
|
||||||
|
io.fpu.dec.wen && fp_sboard.read(id_waddr)
|
||||||
|
} else Bool(false)
|
||||||
|
|
||||||
|
val ctrl_stalld =
|
||||||
|
id_ex_hazard || id_mem_hazard || id_wb_hazard || id_sboard_hazard ||
|
||||||
|
id_ctrl.fp && id_stall_fpu ||
|
||||||
|
id_ctrl.mem && !io.dmem.req.ready ||
|
||||||
|
Bool(!params(BuildRoCC).isEmpty) && wb_reg_rocc_pending && id_ctrl.rocc && !io.rocc.cmd.ready ||
|
||||||
|
id_do_fence ||
|
||||||
|
csr.io.csr_stall
|
||||||
|
ctrl_killd := !io.imem.resp.valid || take_pc || ctrl_stalld || csr.io.interrupt
|
||||||
|
|
||||||
|
io.imem.resp.ready := !ctrl_stalld || csr.io.interrupt
|
||||||
|
io.imem.invalidate := wb_reg_valid && wb_ctrl.fence_i
|
||||||
|
|
||||||
|
io.fpu.valid := !ctrl_killd && id_ctrl.fp
|
||||||
|
io.fpu.killx := ctrl_killx
|
||||||
|
io.fpu.killm := killm_common
|
||||||
|
io.fpu.inst := id_inst
|
||||||
|
io.fpu.fromint_data := ex_rs(0)
|
||||||
|
io.fpu.dmem_resp_val := dmem_resp_valid && dmem_resp_fpu
|
||||||
|
io.fpu.dmem_resp_data := io.dmem.resp.bits.data
|
||||||
|
io.fpu.dmem_resp_type := io.dmem.resp.bits.typ
|
||||||
|
io.fpu.dmem_resp_tag := dmem_resp_waddr
|
||||||
|
|
||||||
|
io.dmem.req.valid := ex_reg_valid && ex_ctrl.mem
|
||||||
|
io.dmem.req.bits.kill := killm_common || mem_xcpt
|
||||||
|
io.dmem.req.bits.cmd := ex_ctrl.mem_cmd
|
||||||
|
io.dmem.req.bits.typ := ex_ctrl.mem_type
|
||||||
|
io.dmem.req.bits.phys := Bool(false)
|
||||||
|
io.dmem.req.bits.addr := Cat(vaSign(ex_rs(0), alu.io.adder_out), alu.io.adder_out(vaddrBits-1,0)).toUInt
|
||||||
|
io.dmem.req.bits.tag := Cat(ex_waddr, ex_ctrl.fp)
|
||||||
|
io.dmem.req.bits.data := Mux(mem_ctrl.fp, io.fpu.store_data, mem_reg_rs2)
|
||||||
|
require(params(CoreDCacheReqTagBits) >= 6)
|
||||||
|
io.dmem.invalidate_lr := wb_xcpt
|
||||||
|
|
||||||
|
io.rocc.cmd.valid := wb_rocc_val
|
||||||
|
io.rocc.exception := wb_xcpt && csr.io.status.xs.orR
|
||||||
|
io.rocc.s := csr.io.status.prv.orR // should we just pass all of mstatus?
|
||||||
|
io.rocc.cmd.bits.inst := new RoCCInstruction().fromBits(wb_reg_inst)
|
||||||
|
io.rocc.cmd.bits.rs1 := wb_reg_wdata
|
||||||
|
io.rocc.cmd.bits.rs2 := wb_reg_rs2
|
||||||
|
|
||||||
|
printf("C%d: %d [%d] pc=[%x] W[r%d=%x][%d] R[r%d=%x] R[r%d=%x] inst=[%x] DASM(%x)\n",
|
||||||
|
io.host.id, csr.io.time(32,0), wb_valid, wb_reg_pc,
|
||||||
|
Mux(rf_wen, rf_waddr, UInt(0)), rf_wdata, rf_wen,
|
||||||
|
wb_reg_inst(19,15), Reg(next=Reg(next=ex_rs(0))),
|
||||||
|
wb_reg_inst(24,20), Reg(next=Reg(next=ex_rs(1))),
|
||||||
|
wb_reg_inst, wb_reg_inst)
|
||||||
|
|
||||||
|
def checkExceptions(x: Seq[(Bool, UInt)]) =
|
||||||
|
(x.map(_._1).reduce(_||_), PriorityMux(x))
|
||||||
|
|
||||||
|
def imm(sel: Bits, inst: Bits) = {
|
||||||
|
val sign = Mux(sel === IMM_Z, SInt(0), inst(31).toSInt)
|
||||||
|
val b30_20 = Mux(sel === IMM_U, inst(30,20).toSInt, sign)
|
||||||
|
val b19_12 = Mux(sel != IMM_U && sel != IMM_UJ, sign, inst(19,12).toSInt)
|
||||||
|
val b11 = Mux(sel === IMM_U || sel === IMM_Z, SInt(0),
|
||||||
|
Mux(sel === IMM_UJ, inst(20).toSInt,
|
||||||
|
Mux(sel === IMM_SB, inst(7).toSInt, sign)))
|
||||||
|
val b10_5 = Mux(sel === IMM_U || sel === IMM_Z, Bits(0), inst(30,25))
|
||||||
|
val b4_1 = Mux(sel === IMM_U, Bits(0),
|
||||||
|
Mux(sel === IMM_S || sel === IMM_SB, inst(11,8),
|
||||||
|
Mux(sel === IMM_Z, inst(19,16), inst(24,21))))
|
||||||
|
val b0 = Mux(sel === IMM_S, inst(7),
|
||||||
|
Mux(sel === IMM_I, inst(20),
|
||||||
|
Mux(sel === IMM_Z, inst(15), Bits(0))))
|
||||||
|
|
||||||
|
Cat(sign, b30_20, b19_12, b11, b10_5, b4_1, b0).toSInt
|
||||||
|
}
|
||||||
|
|
||||||
|
def vaSign(a0: UInt, ea: Bits) = {
|
||||||
|
// efficient means to compress 64-bit VA into vaddrBits+1 bits
|
||||||
|
// (VA is bad if VA(vaddrBits) != VA(vaddrBits-1))
|
||||||
|
val a = a0 >> vaddrBits-1
|
||||||
|
val e = ea(vaddrBits,vaddrBits-1)
|
||||||
|
Mux(a === UInt(0) || a === UInt(1), e != UInt(0),
|
||||||
|
Mux(a === SInt(-1) || a === SInt(-2), e === SInt(-1),
|
||||||
|
e(0)))
|
||||||
|
}
|
||||||
|
|
||||||
|
class RegFile {
|
||||||
|
private val rf = Mem(UInt(width = 64), 31)
|
||||||
|
private val reads = collection.mutable.ArrayBuffer[(UInt,UInt)]()
|
||||||
|
private var canRead = true
|
||||||
|
def read(addr: UInt) = {
|
||||||
|
require(canRead)
|
||||||
|
reads += addr -> Wire(UInt())
|
||||||
|
reads.last._2 := rf(~addr)
|
||||||
|
reads.last._2
|
||||||
|
}
|
||||||
|
def write(addr: UInt, data: UInt) = {
|
||||||
|
canRead = false
|
||||||
|
when (addr != UInt(0)) {
|
||||||
|
rf(~addr) := data
|
||||||
|
for ((raddr, rdata) <- reads)
|
||||||
|
when (addr === raddr) { rdata := data }
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
class Scoreboard(n: Int)
|
||||||
|
{
|
||||||
|
def set(en: Bool, addr: UInt): Unit = update(en, _next | mask(en, addr))
|
||||||
|
def clear(en: Bool, addr: UInt): Unit = update(en, _next & ~mask(en, addr))
|
||||||
|
def read(addr: UInt): Bool = r(addr)
|
||||||
|
def readBypassed(addr: UInt): Bool = _next(addr)
|
||||||
|
|
||||||
|
private val r = Reg(init=Bits(0, n))
|
||||||
|
private var _next = r
|
||||||
|
private var ens = Bool(false)
|
||||||
|
private def mask(en: Bool, addr: UInt) = Mux(en, UInt(1) << addr, UInt(0))
|
||||||
|
private def update(en: Bool, update: UInt) = {
|
||||||
|
_next = update
|
||||||
|
ens = ens || en
|
||||||
|
when (ens) { r := _next }
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
@ -23,7 +23,7 @@ class RocketTile(resetSignal: Bool = null) extends Tile(resetSignal) {
|
|||||||
val icache = Module(new Frontend, { case CacheName => "L1I"; case CoreName => "Rocket" })
|
val icache = Module(new Frontend, { case CacheName => "L1I"; case CoreName => "Rocket" })
|
||||||
val dcache = Module(new HellaCache, { case CacheName => "L1D" })
|
val dcache = Module(new HellaCache, { case CacheName => "L1D" })
|
||||||
val ptw = Module(new PTW(params(NPTWPorts)))
|
val ptw = Module(new PTW(params(NPTWPorts)))
|
||||||
val core = Module(new Core, { case CoreName => "Rocket" })
|
val core = Module(new Rocket, { case CoreName => "Rocket" })
|
||||||
|
|
||||||
dcache.io.cpu.invalidate_lr := core.io.dmem.invalidate_lr // Bypass signal to dcache
|
dcache.io.cpu.invalidate_lr := core.io.dmem.invalidate_lr // Bypass signal to dcache
|
||||||
val dcArb = Module(new HellaCacheArbiter(params(NDCachePorts)))
|
val dcArb = Module(new HellaCacheArbiter(params(NDCachePorts)))
|
||||||
@ -38,6 +38,13 @@ class RocketTile(resetSignal: Bool = null) extends Tile(resetSignal) {
|
|||||||
core.io.imem <> icache.io.cpu
|
core.io.imem <> icache.io.cpu
|
||||||
core.io.ptw <> ptw.io.dpath
|
core.io.ptw <> ptw.io.dpath
|
||||||
|
|
||||||
|
//If so specified, build an FPU module and wire it in
|
||||||
|
params(BuildFPU)
|
||||||
|
.map { bf => bf() }
|
||||||
|
.foreach { fpu =>
|
||||||
|
fpu.io <> core.io.fpu
|
||||||
|
}
|
||||||
|
|
||||||
// Connect the caches and ROCC to the outer memory system
|
// Connect the caches and ROCC to the outer memory system
|
||||||
io.cached <> dcache.io.mem
|
io.cached <> dcache.io.mem
|
||||||
// If so specified, build an RoCC module and wire it in
|
// If so specified, build an RoCC module and wire it in
|
||||||
|
|||||||
Loading…
Reference in New Issue
Block a user