Tests/cocotb (#19)

* wip

* reorg

* update sv int

* apb4 working

* apb3 working

* version bump + ignore runner warning

* remove redundant check

* adding log on failure

* cleaning up verilator version issue

* devcontainer

* Fix missing libpython in GitHub Actions CI environment (#21)

* Initial plan

* Install libpython in GitHub Actions for cocotb tests

Co-authored-by: arnavsacheti <36746504+arnavsacheti@users.noreply.github.com>

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: arnavsacheti <36746504+arnavsacheti@users.noreply.github.com>

---------

Co-authored-by: Copilot <198982749+Copilot@users.noreply.github.com>
This commit is contained in:
Arnav Sacheti
2025-11-10 23:00:28 -08:00
committed by GitHub
parent d7481e71ba
commit a9653c8497
25 changed files with 1417 additions and 364 deletions

View File

@@ -1,15 +1,19 @@
"""APB3 smoke tests for generated multi-register design."""
"""APB3 smoke tests generated from SystemRDL sources."""
from __future__ import annotations
import json
import os
from typing import Any, Iterable
import cocotb
from cocotb.triggers import Timer
WRITE_ADDR = 0x0
READ_ADDR = 0x8
WRITE_DATA = 0xCAFEBABE
READ_DATA = 0x0BAD_F00D
from tests.cocotb_lib.handle_utils import SignalHandle, resolve_handle
class _Apb3SlaveShim:
"""Accessor for the APB3 slave signals on the DUT."""
def __init__(self, dut):
prefix = "s_apb"
self.PSEL = getattr(dut, f"{prefix}_PSEL")
@@ -22,102 +26,161 @@ class _Apb3SlaveShim:
self.PSLVERR = getattr(dut, f"{prefix}_PSLVERR")
class _Apb3MasterShim:
def __init__(self, dut, base: str):
self.PSEL = getattr(dut, f"{base}_PSEL")
self.PENABLE = getattr(dut, f"{base}_PENABLE")
self.PWRITE = getattr(dut, f"{base}_PWRITE")
self.PADDR = getattr(dut, f"{base}_PADDR")
self.PWDATA = getattr(dut, f"{base}_PWDATA")
self.PRDATA = getattr(dut, f"{base}_PRDATA")
self.PREADY = getattr(dut, f"{base}_PREADY")
self.PSLVERR = getattr(dut, f"{base}_PSLVERR")
def _load_config() -> dict[str, Any]:
payload = os.environ.get("RDL_TEST_CONFIG")
if payload is None:
raise RuntimeError("RDL_TEST_CONFIG environment variable was not provided")
return json.loads(payload)
def _apb3_slave(dut):
return getattr(dut, "s_apb", None) or _Apb3SlaveShim(dut)
def _resolve(handle, indices: Iterable[int]):
return resolve_handle(handle, indices)
def _apb3_master(dut, base: str):
return getattr(dut, base, None) or _Apb3MasterShim(dut, base)
def _set_value(handle, indices: Iterable[int], value: int) -> None:
_resolve(handle, indices).value = value
def _get_int(handle, indices: Iterable[int]) -> int:
return int(_resolve(handle, indices).value)
def _build_master_table(dut, masters_cfg: list[dict[str, Any]]) -> dict[str, dict[str, Any]]:
table: dict[str, dict[str, Any]] = {}
for master in masters_cfg:
prefix = master["port_prefix"]
entry = {
"indices": [tuple(idx) for idx in master["indices"]] or [tuple()],
"outputs": {
"PSEL": SignalHandle(dut, f"{prefix}_PSEL"),
"PENABLE": SignalHandle(dut, f"{prefix}_PENABLE"),
"PWRITE": SignalHandle(dut, f"{prefix}_PWRITE"),
"PADDR": SignalHandle(dut, f"{prefix}_PADDR"),
"PWDATA": SignalHandle(dut, f"{prefix}_PWDATA"),
},
"inputs": {
"PRDATA": SignalHandle(dut, f"{prefix}_PRDATA"),
"PREADY": SignalHandle(dut, f"{prefix}_PREADY"),
"PSLVERR": SignalHandle(dut, f"{prefix}_PSLVERR"),
},
}
table[master["inst_name"]] = entry
return table
def _all_index_pairs(table: dict[str, dict[str, Any]]):
for name, entry in table.items():
for idx in entry["indices"]:
yield name, idx
def _write_pattern(address: int, width: int) -> int:
mask = (1 << width) - 1
return ((address * 0x2041) ^ 0xCAFEBABE) & mask
def _read_pattern(address: int, width: int) -> int:
mask = (1 << width) - 1
return ((address ^ 0x0BAD_F00D) + width) & mask
@cocotb.test()
async def test_apb3_read_write_paths(dut):
"""Exercise APB3 slave interface and observe master fanout."""
s_apb = _apb3_slave(dut)
masters = {
"reg1": _apb3_master(dut, "m_apb_reg1"),
"reg2": _apb3_master(dut, "m_apb_reg2"),
"reg3": _apb3_master(dut, "m_apb_reg3"),
}
async def test_apb3_address_decoding(dut) -> None:
"""Exercise the APB3 slave interface against sampled register addresses."""
config = _load_config()
slave = _Apb3SlaveShim(dut)
masters = _build_master_table(dut, config["masters"])
s_apb.PSEL.value = 0
s_apb.PENABLE.value = 0
s_apb.PWRITE.value = 0
s_apb.PADDR.value = 0
s_apb.PWDATA.value = 0
slave.PSEL.value = 0
slave.PENABLE.value = 0
slave.PWRITE.value = 0
slave.PADDR.value = 0
slave.PWDATA.value = 0
for master in masters.values():
master.PRDATA.value = 0
master.PREADY.value = 0
master.PSLVERR.value = 0
for master_name, idx in _all_index_pairs(masters):
entry = masters[master_name]
_set_value(entry["inputs"]["PRDATA"], idx, 0)
_set_value(entry["inputs"]["PREADY"], idx, 0)
_set_value(entry["inputs"]["PSLVERR"], idx, 0)
await Timer(1, units="ns")
# Write to reg1
masters["reg1"].PREADY.value = 1
s_apb.PADDR.value = WRITE_ADDR
s_apb.PWDATA.value = WRITE_DATA
s_apb.PWRITE.value = 1
s_apb.PSEL.value = 1
s_apb.PENABLE.value = 1
addr_mask = (1 << config["address_width"]) - 1
await Timer(1, units="ns")
for txn in config["transactions"]:
master_name = txn["master"]
index = tuple(txn["index"])
entry = masters[master_name]
assert int(masters["reg1"].PSEL.value) == 1, "reg1 should be selected for write"
assert int(masters["reg1"].PWRITE.value) == 1, "Write should propagate to master"
assert int(masters["reg1"].PADDR.value) == WRITE_ADDR, "Address should reach selected master"
assert int(masters["reg1"].PWDATA.value) == WRITE_DATA, "Write data should fan out"
address = txn["address"] & addr_mask
write_data = _write_pattern(address, config["data_width"])
for name, master in masters.items():
if name != "reg1":
assert int(master.PSEL.value) == 0, f"{name} must idle during reg1 write"
_set_value(entry["inputs"]["PREADY"], index, 1)
_set_value(entry["inputs"]["PSLVERR"], index, 0)
assert int(s_apb.PREADY.value) == 1, "Ready must reflect selected master"
assert int(s_apb.PSLVERR.value) == 0, "Write should not signal error"
slave.PADDR.value = address
slave.PWDATA.value = write_data
slave.PWRITE.value = 1
slave.PSEL.value = 1
slave.PENABLE.value = 1
s_apb.PSEL.value = 0
s_apb.PENABLE.value = 0
s_apb.PWRITE.value = 0
masters["reg1"].PREADY.value = 0
await Timer(1, units="ns")
await Timer(1, units="ns")
# Read from reg3
masters["reg3"].PRDATA.value = READ_DATA
masters["reg3"].PREADY.value = 1
masters["reg3"].PSLVERR.value = 0
assert _get_int(entry["outputs"]["PSEL"], index) == 1, f"{master_name} should assert PSEL for write"
assert _get_int(entry["outputs"]["PWRITE"], index) == 1, f"{master_name} should see write direction"
assert _get_int(entry["outputs"]["PADDR"], index) == address, f"{master_name} must receive write address"
assert _get_int(entry["outputs"]["PWDATA"], index) == write_data, f"{master_name} must receive write data"
s_apb.PADDR.value = READ_ADDR
s_apb.PSEL.value = 1
s_apb.PENABLE.value = 1
s_apb.PWRITE.value = 0
for other_name, other_idx in _all_index_pairs(masters):
if other_name == master_name and other_idx == index:
continue
other_entry = masters[other_name]
assert (
_get_int(other_entry["outputs"]["PSEL"], other_idx) == 0
), f"{other_name}{other_idx} should remain idle during {txn['label']}"
await Timer(1, units="ns")
assert int(slave.PREADY.value) == 1, "Slave ready should mirror selected master"
assert int(slave.PSLVERR.value) == 0, "Write should complete without error"
assert int(masters["reg3"].PSEL.value) == 1, "reg3 should be selected for read"
assert int(masters["reg3"].PWRITE.value) == 0, "Read should clear write"
assert int(masters["reg3"].PADDR.value) == READ_ADDR, "Address should reach read target"
slave.PSEL.value = 0
slave.PENABLE.value = 0
slave.PWRITE.value = 0
_set_value(entry["inputs"]["PREADY"], index, 0)
await Timer(1, units="ns")
for name, master in masters.items():
if name != "reg3":
assert int(master.PSEL.value) == 0, f"{name} must idle during reg3 read"
# ------------------------------------------------------------------
# Read phase
# ------------------------------------------------------------------
read_data = _read_pattern(address, config["data_width"])
_set_value(entry["inputs"]["PRDATA"], index, read_data)
_set_value(entry["inputs"]["PREADY"], index, 1)
_set_value(entry["inputs"]["PSLVERR"], index, 0)
assert int(s_apb.PRDATA.value) == READ_DATA, "Read data should return to slave"
assert int(s_apb.PREADY.value) == 1, "Read should acknowledge"
assert int(s_apb.PSLVERR.value) == 0, "Read should not signal error"
slave.PADDR.value = address
slave.PWRITE.value = 0
slave.PSEL.value = 1
slave.PENABLE.value = 1
s_apb.PSEL.value = 0
s_apb.PENABLE.value = 0
masters["reg3"].PREADY.value = 0
await Timer(1, units="ns")
await Timer(1, units="ns")
assert _get_int(entry["outputs"]["PSEL"], index) == 1, f"{master_name} must assert PSEL for read"
assert _get_int(entry["outputs"]["PWRITE"], index) == 0, f"{master_name} should clear write during read"
assert _get_int(entry["outputs"]["PADDR"], index) == address, f"{master_name} must receive read address"
for other_name, other_idx in _all_index_pairs(masters):
if other_name == master_name and other_idx == index:
continue
other_entry = masters[other_name]
assert (
_get_int(other_entry["outputs"]["PSEL"], other_idx) == 0
), f"{other_name}{other_idx} must stay idle during read of {txn['label']}"
assert int(slave.PRDATA.value) == read_data, "Read data should propagate back to the slave"
assert int(slave.PREADY.value) == 1, "Slave ready should acknowledge the read"
assert int(slave.PSLVERR.value) == 0, "Read should not signal an error"
slave.PSEL.value = 0
slave.PENABLE.value = 0
_set_value(entry["inputs"]["PREADY"], index, 0)
_set_value(entry["inputs"]["PRDATA"], index, 0)
await Timer(1, units="ns")