diff options
Diffstat (limited to 'src/storage/cache.cc')
| -rw-r--r-- | src/storage/cache.cc | 51 |
1 files changed, 48 insertions, 3 deletions
diff --git a/src/storage/cache.cc b/src/storage/cache.cc index 67cedda..ec14ce6 100644 --- a/src/storage/cache.cc +++ b/src/storage/cache.cc @@ -1,22 +1,67 @@ #include "cache.h" #include "definitions.h" #include "response.h" +#include "utils.h" #include <bits/stdc++.h> Cache::Cache(int lines, Storage *lower, int delay) { this->data = new std::vector<std::array<signed int, LINE_SIZE>>; - this->data->resize(lines); + this->data->resize(L1_CACHE_SIZE); this->lower = lower; this->delay = delay; - this->lower = nullptr; + this->meta.fill({-1}); } Cache::~Cache() { delete this->data; } Response Cache::write(Accessor accessor, signed int data, int address) { + Response r = WAIT; + + /* Do this first--then process the first cycle immediately. */ + if (this->requester == IDLE) + this->requester = accessor; + + if (this->requester == accessor) { + fetch_resource(address); + if (this->is_waiting == true) + r = BLOCKED; + else if (this->wait_time == 0) { + r = OK; + } + } + + return r; +} + +Response Cache::read( + Accessor accessor, int address, std::array<signed int, LINE_SIZE> &data) +{ return WAIT; } -Response Cache::read(Accessor accessor, int address, std::array<signed int, LINE_SIZE>& data) { return WAIT; } +void Cache::fetch_resource(int expected) +{ + Response r = OK; + int etag, index, atag; + std::array<signed int, LINE_SIZE> actual; + std::array<int, 2> meta; + + get_bit_fields(expected, &etag, &index, nullptr); + meta = this->meta.at(index); + + if (atag != etag) { + // address not in cache + if (this->meta[index][0]) { + // occupant is dirty + // TODO + r = WAIT; + } else { + actual = this->data->at(index); + r = this->lower->read(L1CACHE, expected, actual); + } + } + + this->is_waiting = (r == OK) ? false : true; +} |