riscv/rocket-chip
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Enforce physical-address canonicalization

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When xLen > paddrBits, enforce that physical addresses are zero-extended.
This works by checking that the _virtual_ address is _sign_-extended, then
checking that its sign is positive.
This commit is contained in:
Andrew Waterman 2018-01-02 18:28:59 -08:00
parent 7c9a1b0265
commit ee1a9485df
1 changed files with 2 additions and 2 deletions
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4
src/main/scala/rocket/TLB.scala
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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 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) // 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 refill_ppn = io.ptw.resp.bits.pte.ppn(ppnBits-1, 0)
val do_refill = Bool(usingVM) && io.ptw.resp.valid val do_refill = Bool(usingVM) && io.ptw.resp.valid
val invalidate_refill = state.isOneOf(s_request /* don't care */, s_wait_invalidate) val invalidate_refill = state.isOneOf(s_request /* don't care */, s_wait_invalidate)
val mpu_ppn = Mux(do_refill, refill_ppn, 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 mpu_physaddr = Cat(mpu_ppn, io.req.bits.vaddr(pgIdxBits-1, 0))
val pmp = Module(new PMPChecker(lgMaxSize)) val pmp = Module(new PMPChecker(lgMaxSize))
pmp.io.addr := mpu_physaddr 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_x = fastCheck(_.executable) && pmp.io.x
val prot_eff = fastCheck(Seq(RegionType.PUT_EFFECTS, RegionType.GET_EFFECTS) contains _.regionType) 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 lookup_tag = Cat(io.ptw.ptbr.asid, vpn)
val hitsVec = (0 until totalEntries).map { i => if (!usingVM) false.B else vm_enabled && { val hitsVec = (0 until totalEntries).map { i => if (!usingVM) false.B else vm_enabled && {
var tagMatch = valid(i) var tagMatch = valid(i)