| # SYSRST_CTRL DV document | |
| <!-- Copy this file to hw/ip/sysrst_ctrl/doc/dv/index.md and make changes as needed. | |
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| ## Goals | |
| * **DV** | |
| * Verify all SYSRST_CTRL IP features by running dynamic simulations with a SV/UVM based testbench | |
| * Develop and run all tests based on the [testplan](#testplan) below towards closing code and functional coverage on the IP and all of its sub-modules | |
| * **FPV** | |
| * Verify TileLink device protocol compliance with an SVA based testbench | |
| ## Current status | |
| * [Design & verification stage](../../../README.md) | |
| * [HW development stages](../../../../doc/project_governance/development_stages.md) | |
| * [Simulation results](https://reports.opentitan.org/hw/ip/sysrst_ctrl/dv/latest/report.html) | |
| ## Design features | |
| For detailed information on SYSRST_CTRL design features, please see the [SYSRST_CTRL HWIP technical specification](../README.md). | |
| ## Testbench architecture | |
| SYSRST_CTRL testbench has been constructed based on the [CIP testbench architecture](../../../dv/sv/cip_lib/README.md). | |
| ### Block diagram | |
|  | |
| ### Top level testbench | |
| The top level testbench is located at `hw/ip/sysrst_ctrl/dv/tb.sv`. | |
| It instantiates the SYSRST_CTRL DUT module `hw/ip/sysrst_ctrl/rtl/sysrst_ctrl.sv`. | |
| In addition, it instantiates the following interfaces, connects them to the DUT and sets their handle into `uvm_config_db`: | |
| * [Clock and reset interface](../../../dv/sv/common_ifs/README.md) | |
| * [TileLink host interface](../../../dv/sv/tl_agent/README.md) | |
| * SYSRST_CTRL IOs | |
| * Interrupts ([`pins_if`](../../../dv/sv/common_ifs/README.md)) | |
| * Alerts ([`alert_esc_if`](../../../dv/sv/alert_esc_agent/README.md)) | |
| * Devmode ([`pins_if`](../../../dv/sv/common_ifs/README.md)) | |
| ### Common DV utility components | |
| The following utilities provide generic helper tasks and functions to perform activities that are common across the project: | |
| * [dv_utils_pkg](../../../dv/sv/dv_utils/README.md) | |
| * [csr_utils_pkg](../../../dv/sv/csr_utils/README.md) | |
| ### Compile-time configurations | |
| [list compile time configurations, if any and what are they used for] | |
| ### Global types & methods | |
| All common types and methods defined at the package level can be found in | |
| `sysrst_ctrl_env_pkg`. | |
| ### TL_agent | |
| The SYSRST_CTRL testbench instantiates (already handled in CIP base env) [tl_agent](../../../dv/sv/tl_agent/README.md). | |
| This provides the ability to drive and independently monitor random traffic via the TL host interface into the SYSRST_CTRL device. | |
| ### Alert_agents | |
| SYSRST_CTRL testbench instantiates (already handled in CIP base env) [alert_agents](../../../dv/sv/alert_esc_agent/README.md): | |
| [list alert names]. | |
| The alert_agents provide the ability to drive and independently monitor alert handshakes via alert interfaces in SYSRST_CTRL device. | |
| ### UVM RAL Model | |
| The SYSRST_CTRL RAL model is created with the [`ralgen`](../../../dv/tools/ralgen/README.md) FuseSoC generator script automatically when the simulation is at the build stage. | |
| It can be created manually by invoking [`regtool`](../../../../util/reggen/doc/setup_and_use.md): | |
| ### Stimulus strategy | |
| #### Test sequences | |
| The test sequences reside in `hw/ip/sysrst_ctrl/dv/env/seq_lib`. | |
| All test sequences are extended from `sysrst_ctrl_base_vseq`, which is extended from `cip_base_vseq` and serves as a starting point. | |
| It provides commonly used handles, variables, functions and tasks that the test sequences can simple use / call. | |
| #### Functional coverage | |
| To ensure high quality constrained random stimulus, it is necessary to develop a functional coverage model. | |
| The following covergroups have been developed to prove that the test intent has been adequately met: | |
| * sysrst_ctrl_combo_detect_action_cg: This covergroup will cover all the combo detect actions for combo detect register set 0-3. | |
| * sysrst_ctrl_combo_detect_det_cg: This covergroup will cover the combo detect debounce timer value. | |
| * sysrst_ctrl_combo_precondition_det_cg: This covergroup will cover the combo precondition debounce timer value. | |
| * sysrst_ctrl_auto_block_debounce_ctl_cg: This will cover the auto block enable/disable feature, debounce timer value. | |
| * sysrst_ctrl_combo_intr_status_cg: This covergroup will capture the combo detect interrupt status. | |
| * sysrst_ctrl_key_intr_status_cg: This covergroup will capture the edge detect status for all the inputs. | |
| * sysrst_ctrl_ulp_status_cg: This covergroup will cover the ultra low power status. | |
| * sysrst_ctrl_wkup_status_cg: This will capture the wakeup status event after the low power event is triggered. | |
| * sysrst_ctrl_pin_in_value_cg: This covergroup will cover the raw input values of all the input pins. | |
| * sysrst_ctrl_auto_blk_out_ctl_cg: This covergroup will cover the input selected for auto block and the output value status for the selected input pin. | |
| * pin_cfg_cg: This is the generic covergroup to cover the override and allowed values for the selected input and output values. An array of this covergroup is | |
| created for all the input pins. | |
| * debounce_timer_cg: This is the generic covergroup to cover the debounce timer values for the below register. | |
| key_intr_debounce_ctl | |
| ulp_ac_debounce_ctl | |
| ulp_pwrb_debounce_ctl | |
| ulp_lid_debounce_ctl | |
| ec_rst_ctl | |
| * sysrst_ctrl_key_invert_ctl_cg: This covergroup will cover which input/output pins are allowed to invert their values.The invert values are crossed with the input/output values. | |
| ### Self-checking strategy | |
| #### Scoreboard | |
| The `sysrst_ctrl_scoreboard` is primarily used for end to end checking. | |
| #### Assertions | |
| * TLUL assertions: The `sva/sysrst_ctrl_bind.sv` file binds the `tlul_assert` [assertions](../../tlul/doc/TlulProtocolChecker.md) to the IP to ensure TileLink interface protocol compliance. | |
| * Unknown checks on DUT outputs: The RTL has assertions to ensure all outputs are initialized to known values after coming out of reset. | |
| * Assertions in `tb.sv` | |
| * CheckFlashWrProtRst: Checks flash_wp_l output pin is asserted active low which it is in reset. | |
| * CheckEcPwrOnRst: Checks ec_rst_l_o is asserted active low when it is in reset. | |
| ## Building and running tests | |
| We are using our in-house developed [regression tool](../../../../util/dvsim/README.md) for building and running our tests and regressions. | |
| Please take a look at the link for detailed information on the usage, capabilities, features and known issues. | |
| Here's how to run a smoke test: | |
| ```console | |
| $ $REPO_TOP/util/dvsim/dvsim.py $REPO_TOP/hw/ip/sysrst_ctrl/dv/sysrst_ctrl_sim_cfg.hjson -i sysrst_ctrl_smoke | |
| ``` | |
| ## Testplan | |
| [Testplan](../data/sysrst_ctrl_testplan.hjson) |