diff options
| author | Siddarth-Suresh <65844402+Siddarth-Suresh@users.noreply.github.com> | 2025-03-11 01:31:43 -0400 |
|---|---|---|
| committer | Siddarth-Suresh <65844402+Siddarth-Suresh@users.noreply.github.com> | 2025-03-11 11:32:33 -0400 |
| commit | 7284cc1391dbb250cd6738a75853be7e3576fa41 (patch) | |
| tree | cb4c89f9ccd7ed94868dc4b5d1f73a9fdb5be55a /src | |
| parent | 33c7c78b1c65c375d0291fd435e02ddc9d35681b (diff) | |
Write line, dirty cache eviction, cache load word/line (for future multilevel cache implementation)
Diffstat (limited to 'src')
| -rw-r--r-- | src/storage/cache.cc | 49 | ||||
| -rw-r--r-- | src/storage/dram.cc | 22 |
2 files changed, 55 insertions, 16 deletions
diff --git a/src/storage/cache.cc b/src/storage/cache.cc index 1a8a10b..66603e2 100644 --- a/src/storage/cache.cc +++ b/src/storage/cache.cc @@ -49,10 +49,43 @@ Response Cache::write(Accessor accessor, signed int data, int address) return r; } -Response Cache::read( - Accessor accessor, int address, std::array<signed int, LINE_SIZE> &data) +// TODO: tests for multi level cache +Response Cache::read(Accessor accessor, int address, std::array<signed int, LINE_SIZE> &data) { - return WAIT; + Response r = WAIT; + if (this->requester == IDLE) + this->requester = accessor; + if (this->requester == accessor) { + fetch_resource(address); + if (this->is_waiting) + r = BLOCKED; + else if (this->wait_time == 0) { + int tag, index, offset; + get_bit_fields(address, &tag, &index, &offset); + data = this->data->at(index); + r = OK; + } + } + return r; +} + +Response Cache::read_word(Accessor accessor, int address, signed int &data) +{ + Response r = WAIT; + if (this->requester == IDLE) + this->requester = accessor; + if (this->requester == accessor) { + fetch_resource(address); + if (this->is_waiting) + r = BLOCKED; + else if (this->wait_time == 0) { + int tag, index, offset; + get_bit_fields(address, &tag, &index, &offset); + data = this->data->at(index)->at(offset); + r = OK; + } + } + return r; } void Cache::fetch_resource(int expected) @@ -64,19 +97,21 @@ void Cache::fetch_resource(int expected) get_bit_fields(expected, &tag, &index, &offset); meta = &this->meta.at(index); + actual = this->data->at(index); if (meta->at(0) != tag) { // address not in cache if (meta->at(1) >= 0) { // occupant is dirty - // TODO - r = WAIT; + // writing line to DRam in case of dirty cache eviction + r = this->lower->write_line(L1CACHE, actual, ((index << LINE_SPEC) + (meta->at(0) << (L1_CACHE_SPEC + LINE_SPEC)))); + if (r == OK) { + meta->at(1) = -1; + } } else { - actual = this->data->at(index); r = this->lower->read(L1CACHE, expected, actual); if (r == OK) { meta->at(0) = tag; - meta->at(1) = -1; } } } diff --git a/src/storage/dram.cc b/src/storage/dram.cc index e755c2a..290d38b 100644 --- a/src/storage/dram.cc +++ b/src/storage/dram.cc @@ -28,6 +28,18 @@ void Dram::do_write(signed data, int address) this->data->at(line).at(word) = data; } +void Dram::do_read(std::array<signed int, LINE_SIZE> &data_line, int address) +{ + int line = address / LINE_SIZE; + data_line = this->data->at(line); +} + +void Dram::write_line(std::array<signed int, LINE_SIZE> data_line, int address){ + int line = address / LINE_SIZE; + this->data->at(line) = data_line; +} + + Response Dram::write(Accessor accessor, signed int data, int address) { Response r = WAIT; @@ -51,15 +63,7 @@ Response Dram::write(Accessor accessor, signed int data, int address) return r; } -void Dram::do_read(std::array<signed int, LINE_SIZE> &data_line, int address) -{ - int line = address / LINE_SIZE; - data_line = this->data->at(line); -} - -Response Dram::read( - Accessor accessor, int address, std::array<signed int, LINE_SIZE> &data) -{ +Response Dram::read(Accessor accessor, int address, std::array<signed int, LINE_SIZE>& data) { Response r = WAIT; if (this->requester == IDLE) |