derek/gem5
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

systemc: Send response to TLM side if a packet does not need response

Browse Source 
A completed TLM transaction includes request and response parts.
Currently, if a gem5 packet does not need a reponse, the bridge would not
send BEGIN_RESP to its upstream. It causes stuck on TLM side.

To fix this problem, the bridge should send BEGIN_RESP by itself in this
case.

Change-Id: I318dec21bc3f291693715c0d70bc624addf05076
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/32735
Reviewed-by: Gabe Black <gabeblack@google.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Maintainer: Gabe Black <gabeblack@google.com>
This commit is contained in:
Yu-hsin Wang
2020-08-17 10:54:17 +08:00
parent d892d39f33
commit a7530f798b
1 changed files with 14 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

14
src/systemc/tlm_bridge/tlm_to_gem5.cc
View File

@@ -162,8 +162,15 @@ TlmToGem5Bridge<BITWIDTH>::handleBeginReq(tlm::tlm_generic_payload &trans)
auto tlmSenderState = new TlmSenderState(trans);
pkt->pushSenderState(tlmSenderState);
// If the packet doesn't need a response, we should send BEGIN_RESP by
// ourselves.
bool needsResponse = pkt->needsResponse();
if (bmp.sendTimingReq(pkt)) { // port is free -> send END_REQ immediately
sendEndReq(trans);
if (!needsResponse) {
auto delay = sc_core::SC_ZERO_TIME;
sendBeginResp(trans, delay);
}
trans.release();
} else { // port is blocked -> wait for retry before sending END_REQ
waitForRetry = true;
@@ -429,12 +436,19 @@ TlmToGem5Bridge<BITWIDTH>::recvReqRetry()
sc_assert(pendingRequest != nullptr);
sc_assert(pendingPacket != nullptr);
// If the packet doesn't need a response, we should send BEGIN_RESP by
// ourselves.
bool needsResponse = pendingPacket->needsResponse();
if (bmp.sendTimingReq(pendingPacket)) {
waitForRetry = false;
pendingPacket = nullptr;
auto &trans = *pendingRequest;
sendEndReq(trans);
if (!needsResponse) {
auto delay = sc_core::SC_ZERO_TIME;
sendBeginResp(trans, delay);
}
trans.release();
pendingRequest = nullptr;