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O3: Fetch from the microcode ROM when needed.

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This commit is contained in:
Gabe Black 2011-02-13 17:40:07 -08:00
parent 7c763b34c9
commit f036fd9748
1 changed files with 12 additions and 5 deletions
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17
src/cpu/o3/fetch_impl.hh
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@ -1070,6 +1070,8 @@ DefaultFetch<Impl>::fetch(bool &status_change)
Addr pcOffset = fetchOffset[tid];
Addr fetchAddr = (thisPC.instAddr() + pcOffset) & BaseCPU::PCMask;
bool inRom = isRomMicroPC(thisPC.microPC());
// If returning from the delay of a cache miss, then update the status
// to running, otherwise do the cache access. Possibly move this up
// to tick() function.
@ -1083,7 +1085,7 @@ DefaultFetch<Impl>::fetch(bool &status_change)
Addr block_PC = icacheBlockAlignPC(fetchAddr);
// Unless buffer already got the block, fetch it from icache.
if (!cacheDataValid[tid] || block_PC != cacheDataPC[tid]) {
if (!(cacheDataValid[tid] && block_PC == cacheDataPC[tid]) && !inRom) {
DPRINTF(Fetch, "[tid:%i]: Attempting to translate and read "
"instruction, starting at PC %s.\n", tid, thisPC);
@ -1155,7 +1157,7 @@ DefaultFetch<Impl>::fetch(bool &status_change)
!predictedBranch) {
// If we need to process more memory, do it now.
if (!curMacroop && !predecoder.extMachInstReady()) {
if (!(curMacroop || inRom) && !predecoder.extMachInstReady()) {
if (ISA_HAS_DELAY_SLOT && pcOffset == 0) {
// Walk past any annulled delay slot instructions.
Addr pcAddr = thisPC.instAddr() & BaseCPU::PCMask;
@ -1181,7 +1183,7 @@ DefaultFetch<Impl>::fetch(bool &status_change)
// Extract as many instructions and/or microops as we can from
// the memory we've processed so far.
do {
if (!curMacroop) {
if (!(curMacroop || inRom)) {
if (predecoder.extMachInstReady()) {
ExtMachInst extMachInst;
@ -1202,8 +1204,13 @@ DefaultFetch<Impl>::fetch(bool &status_change)
break;
}
}
if (curMacroop) {
staticInst = curMacroop->fetchMicroop(thisPC.microPC());
if (curMacroop || inRom) {
if (inRom) {
staticInst = cpu->microcodeRom.fetchMicroop(
thisPC.microPC(), curMacroop);
} else {
staticInst = curMacroop->fetchMicroop(thisPC.microPC());
}
if (staticInst->isLastMicroop()) {
curMacroop = NULL;
pcOffset = 0;