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Merge pull request #1171 from freechipsproject/fix-msb-check

Enforce physical-address canonicalization
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Andrew Waterman 2018-01-03 12:06:18 -08:00 committed by GitHub
commit 206892899f
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2 changed files with 4 additions and 7 deletions

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@ -744,11 +744,8 @@ class Rocket(implicit p: Parameters) extends CoreModule()(p)
def encodeVirtualAddress(a0: UInt, ea: UInt) = if (vaddrBitsExtended == vaddrBits) ea else {
// 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).asSInt
val msb =
Mux(a === UInt(0) || a === UInt(1), e =/= SInt(0),
Mux(a.asSInt === SInt(-1) || a.asSInt === SInt(-2), e === SInt(-1), e(0)))
val a = a0.asSInt >> vaddrBits
val msb = Mux(a === 0.S || a === -1.S, ea(vaddrBits), !ea(vaddrBits-1))
Cat(msb, ea(vaddrBits-1,0))
}

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@ -98,12 +98,11 @@ class TLB(instruction: Boolean, lgMaxSize: Int, nEntries: Int)(implicit edge: TL
val vm_enabled = Bool(usingVM) && io.ptw.ptbr.mode(io.ptw.ptbr.mode.getWidth-1) && priv_uses_vm && !io.req.bits.passthrough
// share a single physical memory attribute checker (unshare if critical path)
val vpn = io.req.bits.vaddr(vaddrBits-1, pgIdxBits)
val refill_ppn = io.ptw.resp.bits.pte.ppn(ppnBits-1, 0)
val do_refill = Bool(usingVM) && io.ptw.resp.valid
val invalidate_refill = state.isOneOf(s_request /* don't care */, s_wait_invalidate)
val mpu_ppn = Mux(do_refill, refill_ppn,
Mux(vm_enabled, entries.last.ppn, vpn))
Mux(vm_enabled, entries.last.ppn, io.req.bits.vaddr >> pgIdxBits))
val mpu_physaddr = Cat(mpu_ppn, io.req.bits.vaddr(pgIdxBits-1, 0))
val pmp = Module(new PMPChecker(lgMaxSize))
pmp.io.addr := mpu_physaddr
@ -122,6 +121,7 @@ class TLB(instruction: Boolean, lgMaxSize: Int, nEntries: Int)(implicit edge: TL
val prot_x = fastCheck(_.executable) && pmp.io.x
val prot_eff = fastCheck(Seq(RegionType.PUT_EFFECTS, RegionType.GET_EFFECTS) contains _.regionType)
val vpn = io.req.bits.vaddr(vaddrBits-1, pgIdxBits)
val lookup_tag = Cat(io.ptw.ptbr.asid, vpn)
val hitsVec = (0 until totalEntries).map { i => if (!usingVM) false.B else vm_enabled && {
var tagMatch = valid(i)