sw/device/tests/dif/dif_entropy_src_smoketest.c

// Copyright lowRISC contributors.
// Licensed under the Apache License, Version 2.0, see LICENSE for details.
// SPDX-License-Identifier: Apache-2.0

#include "sw/device/lib/base/memory.h"
#include "sw/device/lib/base/mmio.h"
#include "sw/device/lib/dif/dif_entropy_src.h"
#include "sw/device/lib/runtime/log.h"
#include "sw/device/lib/testing/check.h"
#include "sw/device/lib/testing/test_framework/test_main.h"

#include "hw/top_earlgrey/sw/autogen/top_earlgrey.h"

const test_config_t kTestConfig;

const size_t kEntropyDataNumWords = 12;

const uint32_t kExpectedEntropyData[] = {
    0xa8f49c0d, 0x148ca619, 0xd1818b93, 0x25f2397d, 0x32955611, 0x0aca4b8e,
    0xc0956655, 0x80735507, 0x4cf2b852, 0x97e50e09, 0x39649525, 0x6a2795f0,
};

bool test_main() {
  const dif_entropy_src_params_t params = {
      .base_addr = mmio_region_from_addr(TOP_EARLGREY_ENTROPY_SRC_BASE_ADDR),
  };
  dif_entropy_src_t entropy;
  CHECK(dif_entropy_src_init(params, &entropy) == kDifEntropySrcOk);

  // Disable entropy for test purpose, as it has been turned on by ROM
  CHECK(dif_entropy_src_disable(&entropy) == kDifEntropySrcOk);

  const dif_entropy_src_config_t config = {
      .mode = kDifEntropySrcModeLfsr,
      .tests =
          {
              [kDifEntropySrcTestRepCount] = false,
              [kDifEntropySrcTestAdaptiveProportion] = false,
              [kDifEntropySrcTestBucket] = false,
              [kDifEntropySrcTestMarkov] = false,
              [kDifEntropySrcTestMailbox] = false,
              [kDifEntropySrcTestVendorSpecific] = false,
          },
      // this field needs to manually toggled by software.  Disable for now
      .reset_health_test_registers = false,
      .single_bit_mode = kDifEntropySrcSingleBitModeDisabled,
      .route_to_firmware = true,
      .sample_rate = 2,
      .lfsr_seed = 2,
  };
  CHECK(dif_entropy_src_configure(&entropy, config) == kDifEntropySrcOk);

  uint32_t entropy_data[kEntropyDataNumWords];
  uint32_t result = 0;
  for (uint32_t i = 0; i < kEntropyDataNumWords; ++i) {
    // wait for entropy to become available
    while (dif_entropy_src_read(&entropy, &entropy_data[i]) != kDifEntropySrcOk)
      ;
    LOG_INFO("received 0x%x, expectecd 0x%x", entropy_data[i],
             kExpectedEntropyData[i]);
    result |= entropy_data[i] ^ kExpectedEntropyData[i];
  }

  return true;
}