csrng_testplan.hjson

// Copyright lowRISC contributors.
// Licensed under the Apache License, Version 2.0, see LICENSE for details.
// SPDX-License-Identifier: Apache-2.0
{
  name: "csrng"
  import_testplans: ["hw/dv/tools/dvsim/testplans/csr_testplan.hjson",
                     "hw/dv/tools/dvsim/testplans/intr_test_testplan.hjson",
                     "hw/dv/tools/dvsim/testplans/alert_test_testplan.hjson",
                     "hw/dv/tools/dvsim/testplans/tl_device_access_types_testplan.hjson",
                     "hw/dv/tools/dvsim/testplans/stress_all_with_reset_testplan.hjson",
                     "csrng_sec_cm_testplan.hjson"]
  testpoints: [
    {
      name: smoke
      desc: '''
            Verify that sending an instantiate command via the SW path returns OK.
            Instantiate the CSRNG with flag0 set to true and clen set to 12.
            Verify that sending a generate command via the SW path returns glen=1 number of words followed by an OK.
            '''
      stage: V1
      tests: ["csrng_smoke"]
    }
    {
      name: interrupts
      desc: '''
            This test verifies the behavior of the Interrupt State Register.
            Verify cs_cmd_req_done interrupt asserts when glen number of genbit words have been generated.
            Verify cs_entropy_req interrupt asserts when instantiate or reseed is called with flag0
            set to false.
            Verify cs_hw_inst_exc interrupt asserts when any of the application interfaces responds with a CSRNG_ERROR response status signal.
            Verify cs_fatal_err interrupt asserts when any bit of err_code register is set.
            Verify that each interrupt clears back to 0 after writing the corresponding interrupt state bit.
            '''
      stage: V2
      tests: ["csrng_intr"]
    }
    {
      //TODO For the following untested features add it to the test or create explicit coverpoints in csrng_cmd_cg:
      //TODO - Invalid MuBi values for flag0 are currently untested.
      //TODO - Illegal commands are currently untested.
      //TODO - Fatal alerts are currently untested.
      name: alerts
      desc: '''
            Verify recov_alert asserts when recov_alert_sts becomes non-zero.
            Verify each respective bit of recov_alert_sts asserts when:
            - Either of the 3 values in the control register are not valid kMultiBitBool values.
            - When an initiate or reseed command is sent where flag0 is not a valid kMultiBitBool value.
            - The genbits bus value is equal to the prior valid value.
            - When an illegal command is used (0x0,0x6-0xf).
            Verify that writing zeros to the recoverable alert status register resets all the status bits.
            Verify fatal_alert asserts when:
            - An illegal state is reached.
            - The AES block raises a fatal alert.
            - There is an integrity failure on the bus (this is covered by an automated test).
            '''
      stage: V2
      tests: ["csrng_alert"]
    }
    {
      name: err
      desc: '''
            Verify err_code register bits assert when:
            - An error has been detected in any of the internal fifos and the corresponding write/read/state bits.
            - An illegal state is reached in any of the 6 state machines.
            - An error is detected in the generate command counter.
            Verify that the err_code register clears all bits after reset.
            '''
      stage: V2
      tests: ["csrng_err"]
    }
    {
      //TODO For the following untested features add it to the test or create explicit coverpoints in csrng_cmd_cg:
      //TODO - Verification of otp_en_csrng_sw_app_read is currently untested.
      //TODO - FIPS bit going low from entropy source is currently untested.
      name: cmds
      desc: '''
            Verify all csrng commands req/status behave as predicted on all applications: HW0, HW1 and SW.
            Verify above for all valid values of acmd, clen, flags, glen.
            Verify for multiple hw app interfaces running in parallel.
            Verify sw/hw app interfaces running in parallel.
            Verify main_sm_state for sw/hw apps.
            Verify that genbits generates the amount specified by glen.
            Verify fips bit is set to the inverse of flag0 that was used on the last initialize or reseed.
            Verify that if otp_en_csrng_sw_app_read is set, genbits and int_state_value registers are readable, and unreadable otherwise.
            Verify that when AES_HALT is set during a generate command that no request is sent to the AES block.
            Verify commands with continuous/non-continuous valid.
            Verify that if FIPS bit drops at input from entropy source that the generated block also has FIPS low.
            '''
      stage: V2
      tests: ["csrng_cmds"]
    }
    {
      name: life cycle
      desc: '''
            Verify lifecycle hardware debug mode.
            When lc_hw_debug_en_i is set to on, the seed from the entropy source must be xor'ed with the diversification value.
            '''
      stage: V2
      tests: ["csrng_cmds"]
    }
    {
      name: stress_all
      desc: '''
            Combine the other individual testpoints while injecting TL errors and running CSR tests in parallel.
            '''
      stage: V2
      tests: ["csrng_stress_all"]
    }
  ]

  covergroups: [
    {
      //TODO Configuration for enable is currently not covered.
      name: csrng_cfg_cg
      desc: '''
            Covers that all csrng configuration options have been tested.
            Individual config settings that will be covered include:
            - otp_en_cs_sw_app_read
            - sw_app_enable
            - read_int_state
            - enable
            - regwen has been true and false
            - intr_state has had each bit set and unset at least once (handled in comportable ip coverage)
            Cross:
            - intr_enable and intr_state (handled in comportable ip coverage)
            '''
    }
    {
      name: csrng_cmds_cg
      desc: '''
            Covers that all csrng commands and variations have been tested for all apps.
            Individual commands and command options that will be covered include:
            - app
            - acmd, clen, flags, glen
            - continuous/non-continuous valid
            Crosses of
            - app/acmd
            - acmd/clen
            - acmd/flag0
            - acmd/glen
            - For the instantiate and reseed command:
              - flag0 false and clen 0
              - flag0 false and clen >0
              - flag0 true and clen 0
              - flag0 true and clen >0
            '''
    }
    {
      name: csrng_sts_cg
      desc: '''
            Covers all possible hw_exc_sts responses from each HW instance and the sub-fields of
            sw_cmd_sts, which are cmd_rdy and cmd_sts.
            '''
    }
    {
      name: csrng_err_code_cg
      desc: '''
            Covers all possible fatal errors and possible AES FSM errors inside CSRNG.
            '''
    }
    {
      name: csrng_err_code_test_cg
      desc: '''
            Covers ERR_CODE_TEST register values for setting up fatal errors.
            '''
    }
    {
      name: csrng_recov_alert_sts_cg
      desc: '''
            Covers all possible recoverable alert cases.
            '''
    }
    {
      name: csrng_sfifo_cg
      desc: '''
            Covers each app's stage FIFO statuses.
            - cp_hw0_cmd_depth, cp_hw1_cmd_depth, cp_sw_cmd_depth : Covers current number of commands in FIFO
            - cp_hw0_genbits_depth, cp_hw1_genbits_depth, cp_sw_genbits_depth : Covers current number of genbit responses in FIFO
            - cmd_depth_cross : Cross for checking each command FIFO status in different apps
            - genbits_depth_cross : Cross for checking genbits FIFO status in different apps
            - hw0_cmd_push_cross, hw1_cmd_push_cross, sw_cmd_push_cross : command FIFO fill status x command FIFO write valid x command FIFO write ready
            - hw0_cmd_pop_cross, hw1_cmd_pop_cross, sw_cmd_pop_cross : command FIFO fill status x command FIFO read ready
            - hw0_genbits_pop_cross, hw1_genbits_pop_cross, sw_genbits_pop_cross : genbits FIFO fill status x genbits FIFO read valid x genbits FIFO read ready
            '''
    }
  ]
}