commit 78fb2c1a5d5e422bf14f134d677a83e3022238f1
author Tuan Ta <qtt2@cornell.edu> Mon Jan 22 13:00:35 2018 -0500
committer Tuan Ta <qtt2@cornell.edu> Thu Jun 14 22:41:23 2018 +0000
tree d315ea11d7fdbd95a95b8adac5e2cbe065ee26b2
parent 7bab1d0aff897bc23b5677a51ae67b8cc32953dc

arch: support issuing Atomic Mem Operation (AMO) requests

This patch adds two new functions named amoMemAtomic used in Atomic CPU
model and initiateMemAMO used in Timing CPU models to issue AMO requests
to the memory system.

Change-Id: I962bdc0e5f25b72c170d96ebc136f29a2b230d5e
Reviewed-on: https://gem5-review.googlesource.com/8186
Reviewed-by: Anthony Gutierrez <anthony.gutierrez@amd.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Anthony Gutierrez <anthony.gutierrez@amd.com>

src/arch/generic/memhelpers.hh

diff --git a/src/arch/generic/memhelpers.hh b/src/arch/generic/memhelpers.hh
index 35e666b..6fe1707 100644
--- a/src/arch/generic/memhelpers.hh
+++ b/src/arch/generic/memhelpers.hh
@@ -121,4 +121,36 @@
     return fault;
 }
 
+/// Do atomic read-modify-write (AMO) in atomic mode
+template <class XC, class MemT>
+Fault
+amoMemAtomic(XC *xc, Trace::InstRecord *traceData, MemT &mem, Addr addr,
+             Request::Flags flags, AtomicOpFunctor *amo_op)
+{
+    assert(amo_op);
+
+    // mem will hold the previous value at addr after the AMO completes
+    memset(&mem, 0, sizeof(mem));
+
+    Fault fault = xc->amoMem(addr, (uint8_t *)&mem, sizeof(MemT), flags,
+                             amo_op);
+
+    if (fault == NoFault) {
+        mem = TheISA::gtoh(mem);
+        if (traceData)
+            traceData->setData(mem);
+    }
+    return fault;
+}
+
+/// Do atomic read-modify-wrote (AMO) in timing mode
+template <class XC, class MemT>
+Fault
+initiateMemAMO(XC *xc, Trace::InstRecord *traceData, Addr addr, MemT& mem,
+               Request::Flags flags, AtomicOpFunctor *amo_op)
+{
+    assert(amo_op);
+    return xc->initiateMemAMO(addr, sizeof(MemT), flags, amo_op);
+}
+
 #endif