vortex/hw/unittest/mem_streamer/ram.cpp
2023-11-05 18:51:31 -08:00

123 lines
3.5 KiB
C++

// Copyright © 2019-2023
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#include "ram.h"
#include "memsim.h"
RAM::RAM() {
ram_.clear();
is_rsp_active_ = false;
is_rsp_stall_ = false;
}
bool RAM::check_duplicate_req(req_t req) {
for(int i = 0; i < ram_.size(); i++) {
if (ram_[i].addr == req.addr) {
std::cout<<"RAM: Duplicate entry. Do not insert..."<<std::endl;
return true;
}
}
return false;
}
int RAM::simulate_cycle_delay() {
std::cout<<"RAM: # entries: "<<ram_.size()<<std::endl;
int dequeue_index = -1;
for (int i = 0; i < ram_.size(); i++) {
if (!is_rsp_stall_) {
if (ram_[i].cycles_left > 0) {
ram_[i].cycles_left -= 1;
}
}
std::cout<<"RAM: # cycles left: "<<ram_[i].cycles_left<<std::endl;
if (ram_[i].cycles_left == 0) {
dequeue_index = i;
}
}
return dequeue_index;
}
void RAM::insert_req(req_t req) {
if ( !(this->check_duplicate_req(req)) && req.valid && !req.rw) {
req_t r;
r.valid = req.valid;
r.rw = req.rw;
r.byteen = req.byteen;
r.addr = req.addr;
r.data = req.data;
r.tag = req.tag & 0b11;
// Store metadata
r.cycles_left = MEM_LATENCY;
std::cout<<"RAM: Insert entry... "<<std::endl;
std::cout<<"Write? : "<<req.rw<<std::endl;
ram_.push_back(r);
}
}
uint8_t RAM::is_ready() {
// return generate_rand(0b1000, 0b1111);
return 0b1111;
}
rsp_t RAM::schedule_rsp() {
rsp_t rsp;
int dequeue_index = this->simulate_cycle_delay();
if (!is_rsp_active_) {
if (dequeue_index != -1) {
std::cout<<"RAM: Scheduling response... "<<std::endl;
is_rsp_active_ = true;
rsp.valid = 1;
rsp.mask = generate_rand_mask(ram_[dequeue_index].valid);
rsp.data = generate_rand(0x20000000, 0x30000000);
rsp.tag = ram_[dequeue_index].tag;
std::cout<<std::hex;
std::cout<<"RAM: Response mask: "<<+rsp.mask<<" | Required mask: "<<+ram_[dequeue_index].valid<<std::endl;
ram_[dequeue_index].rsp_sent_mask = rsp.mask;
ram_[dequeue_index].valid = ram_[dequeue_index].valid & ~ram_[dequeue_index].rsp_sent_mask;
if (0 == ram_[dequeue_index].valid) {
ram_.erase(ram_.begin() + dequeue_index);
is_rsp_stall_ = false;
std::cout<<"RAM: Clear entry... "<<std::endl;
} else {
is_rsp_stall_ = true;
std::cout<<"RAM: Stall... "<<std::endl;
}
} else {
rsp.valid = false;
}
}
return rsp;
}
// Schedule response for only one cycle
void RAM::halt_rsp(rsp_t rsp) {
if (is_rsp_active_ && rsp.valid && rsp.ready) {
std::cout<<"RAM: Halt response..."<<std::endl;
is_rsp_active_ = false;
}
}