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Diffstat (limited to 'src/mem/simple_dram.cc')
-rw-r--r--src/mem/simple_dram.cc25
1 files changed, 18 insertions, 7 deletions
diff --git a/src/mem/simple_dram.cc b/src/mem/simple_dram.cc
index bd700c09d..7e377b861 100644
--- a/src/mem/simple_dram.cc
+++ b/src/mem/simple_dram.cc
@@ -70,7 +70,7 @@ SimpleDRAM::SimpleDRAM(const SimpleDRAMParams* p) :
writeThresholdPerc(p->write_thresh_perc),
tWTR(p->tWTR), tBURST(p->tBURST),
tRCD(p->tRCD), tCL(p->tCL), tRP(p->tRP), tRAS(p->tRAS),
- tRFC(p->tRFC), tREFI(p->tREFI),
+ tRFC(p->tRFC), tREFI(p->tREFI), tRRD(p->tRRD),
tXAW(p->tXAW), activationLimit(p->activation_limit),
memSchedPolicy(p->mem_sched_policy), addrMapping(p->addr_mapping),
pageMgmt(p->page_policy),
@@ -988,14 +988,25 @@ SimpleDRAM::processNextReqEvent()
}
void
-SimpleDRAM::recordActivate(Tick act_tick, uint8_t rank)
+SimpleDRAM::recordActivate(Tick act_tick, uint8_t rank, uint8_t bank)
{
assert(0 <= rank && rank < ranksPerChannel);
assert(actTicks[rank].size() == activationLimit);
DPRINTF(DRAM, "Activate at tick %d\n", act_tick);
- // if the activation limit is disabled then we are done
+ // start by enforcing tRRD
+ for(int i = 0; i < banksPerRank; i++) {
+ // next activate must not happen before tRRD
+ banks[rank][i].actAllowedAt = act_tick + tRRD;
+ }
+ // tRC should be added to activation tick of the bank currently accessed,
+ // where tRC = tRAS + tRP, this is just for a check as actAllowedAt for same
+ // bank is already captured by bank.freeAt and bank.tRASDoneAt
+ banks[rank][bank].actAllowedAt = act_tick + tRAS + tRP;
+
+ // next, we deal with tXAW, if the activation limit is disabled
+ // then we are done
if (actTicks[rank].empty())
return;
@@ -1061,24 +1072,24 @@ SimpleDRAM::doDRAMAccess(DRAMPacket* dram_pkt)
// any waiting for banks account for in freeAt
actTick = bank.freeAt - tCL - tRCD;
bank.tRASDoneAt = actTick + tRAS;
- recordActivate(actTick, dram_pkt->rank);
+ recordActivate(actTick, dram_pkt->rank, dram_pkt->bank);
// sample the number of bytes accessed and reset it as
// we are now closing this row
bytesPerActivate.sample(bank.bytesAccessed);
bank.bytesAccessed = 0;
}
+ DPRINTF(DRAM, "doDRAMAccess::bank.freeAt is %lld\n", bank.freeAt);
} else if (pageMgmt == Enums::close) {
actTick = curTick() + addDelay + accessLat - tRCD - tCL;
- recordActivate(actTick, dram_pkt->rank);
+ recordActivate(actTick, dram_pkt->rank, dram_pkt->bank);
// If the DRAM has a very quick tRAS, bank can be made free
// after consecutive tCL,tRCD,tRP times. In general, however,
// an additional wait is required to respect tRAS.
bank.freeAt = std::max(actTick + tRAS + tRP,
actTick + tRCD + tCL + tRP);
-
- DPRINTF(DRAM,"doDRAMAccess::bank.freeAt is %lld\n",bank.freeAt);
+ DPRINTF(DRAM, "doDRAMAccess::bank.freeAt is %lld\n", bank.freeAt);
bytesPerActivate.sample(burstSize);
} else
panic("No page management policy chosen\n");