| # Copyright lowRISC contributors. |
| # Licensed under the Apache License, Version 2.0, see LICENSE for details. |
| # SPDX-License-Identifier: Apache-2.0 |
| |
| from .sim import OTBNSim |
| |
| _TEST_RND_DATA = \ |
| 0x99999999_99999999_99999999_99999999_99999999_99999999_99999999_99999999 |
| |
| # This is the default seed for URND PRNG. Note that the actualy URND value will |
| # be random since we are modelling PRNG inside the URND register model. |
| _TEST_URND_DATA = [ |
| 0x84ddfadaf7e1134d, 0x70aa1c59de6197ff, |
| 0x25a4fe335d095f1e, 0x2cba89acbe4a07e9 |
| ] |
| |
| |
| class StandaloneSim(OTBNSim): |
| def run(self, verbose: bool) -> int: |
| '''Run until ECALL. |
| |
| Return the number of cycles taken. |
| |
| ''' |
| insn_count = 0 |
| # ISS will stall at start until URND data is valid; immediately set it |
| # valid when in free running mode as nothing else will. |
| self.state.wsrs.URND.set_seed(_TEST_URND_DATA) |
| while self.state.running(): |
| self.step(verbose) |
| insn_count += 1 |
| |
| if self.state.wsrs.RND.pending_request: |
| # If an instruction requests RND data, make it available |
| # immediately. |
| self.state.wsrs.RND.set_unsigned(_TEST_RND_DATA) |
| |
| return insn_count |
