Source code for bag3_digital.measurement.stdcells.reset_sync

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from __future__ import annotations

from typing import Any, Mapping, Optional, Sequence
from pathlib import Path
import matplotlib.pyplot as plt

from bag.simulation.cache import SimulationDB, DesignInstance
from bag.simulation.measure import MeasurementManager
from bag.simulation.data import SimData
from bag.concurrent.util import GatherHelper

from bag3_testbenches.measurement.tran.digital import DigitalTranTB
from bag3_testbenches.measurement.digital.util import setup_digital_tran


class ResetSyncMeas(MeasurementManager):
    async def async_measure_performance(self, name: str, sim_dir: Path, sim_db: SimulationDB,
                                        dut: Optional[DesignInstance],
                                        harnesses: Optional[Sequence[DesignInstance]] = None) -> Mapping[str, Any]:
        helper = GatherHelper()
        sim_envs = self.specs['sim_envs']
        for sim_env in sim_envs:
            helper.append(self.async_meas_pvt(name, sim_dir / sim_env, sim_db, dut, harnesses, sim_env))

        meas_results = await helper.gather_err()
        results = {}
        for idx, sim_env in enumerate(sim_envs):
            results[sim_env] = meas_results[idx]
        self.plot_results(results)
        return results

    async def async_meas_pvt(self, name: str, sim_dir: Path, sim_db: SimulationDB, dut: Optional[DesignInstance],
                             harnesses: Optional[Sequence[DesignInstance]], pvt: str) -> SimData:
        # create load
        load_list = [dict(pin='rst_sync', type='cap', value='c_load'),
                     dict(pin='rstb_sync', type='cap', value='c_load')]

        # sinusoidal clk and clkb
        load_list.extend([dict(pin='clk', type='vsin', value=dict(vo='v_VDD/2', va='v_VDD/2', freq='1/t_per')),
                          dict(pin='clkb', type='vsin', value=dict(vo='v_VDD/2', va='v_VDD/2', freq='1/t_per',
                                                                   sinephase='-180'))])

        # asynchronous rst
        pulse_list = [dict(pin='rst_async', tper='3*t_per', tpw='t_per/2', trf='t_rf', td='t_per/4')]

        tb_params = dict(
            pulse_list=pulse_list,
            load_list=load_list,
            sim_envs=[pvt],
            save_outputs=['clk', 'clkb', 'rst_async', 'rst_sync', 'rstb_sync'],
        )
        tbm_specs, tb_params = setup_digital_tran(self.specs, dut, **tb_params)
        tbm = self.make_tbm(DigitalTranTB, tbm_specs)
        sim_results = await sim_db.async_simulate_tbm_obj(name, sim_dir, dut, tbm, tb_params, harnesses=harnesses)
        return sim_results.data

    @classmethod
    def plot_results(cls, results: Mapping[str, SimData]) -> None:
        fig, [ax0, ax1, ax2] = plt.subplots(3, 1)
        ax0.set(xlabel='Time (ns)', ylabel='rst_async (V)')
        ax1.set(xlabel='Time (ns)', ylabel='clk (V)')
        ax2.set(xlabel='Time (ns)', ylabel='rst_sync (V)')
        ax0.grid()
        ax1.grid()
        ax2.grid()
        for sim_env, data in results.items():
            ax0.plot(data['time'] * 1e9, data['rst_async'][0], label=sim_env)
            ax1.plot(data['time'] * 1e9, data['clk'][0], label=sim_env)
            ax2.plot(data['time'] * 1e9, data['rst_sync'][0], label=sim_env)
        ax0.legend()
        ax1.legend()
        ax2.legend()
        plt.tight_layout()
        plt.show()