[sival] Backport entropy_src_fw_override_test to earlgrey_es_sival

sw/device/lib/dif/dif_entropy_src.c

@@ -173,6 +173,21 @@ dif_result_t dif_entropy_src_fw_override_configure(
  return kDifOk;
 }
 
+dif_result_t dif_entropy_src_fw_override_sha3_start_insert(
+ const dif_entropy_src_t *entropy_src, dif_toggle_t enabled) {
+ if (entropy_src == NULL) {
+ return kDifBadArg;
+ }
+
+ uint32_t reg = bitfield_field32_write(
+ 0, ENTROPY_SRC_FW_OV_SHA3_START_FW_OV_INSERT_START_FIELD,
+ dif_toggle_to_multi_bit_bool4(enabled));
+ mmio_region_write32(entropy_src->base_addr,
+ ENTROPY_SRC_FW_OV_SHA3_START_REG_OFFSET, reg);
+
+ return kDifOk;
+}
+
 dif_result_t dif_entropy_src_health_test_configure(
  const dif_entropy_src_t *entropy_src,
  dif_entropy_src_health_test_config_t config) {
@@ -539,7 +554,7 @@ dif_result_t dif_entropy_src_observe_fifo_nonblocking_read(
  return kDifOk;
 }
 
-dif_result_t dif_entropy_src_observe_fifo_write(
+dif_result_t dif_entropy_src_fw_ov_data_write(
  const dif_entropy_src_t *entropy_src, const uint32_t *buf, size_t len,
  size_t *written) {
  if (entropy_src == NULL || buf == NULL) {

sw/device/lib/dif/dif_entropy_src.h

@@ -81,10 +81,10 @@ typedef enum dif_entropy_src_main_fsm {
  */
 typedef struct dif_entropy_src_fw_override_config {
  /**
- * Enables firmware to insert entropy bits back into the pre-conditioner block
- * via `dif_entropy_fifo_write()` calls. This feature is useful when the
- * firmware is required to implement additional health checks, and to perform
- * known answer tests of the preconditioner function.
+ * Enables firmware to insert entropy bits back into the pre-conditioner FIFO
+ * via `dif_entropy_src_fw_ov_data_write()` calls. This feature is useful when
+ * the firmware is required to implement additional health checks, and to
+ * perform known answer tests of the conditioner.
  *
  * To take effect, this requires the firmware override feature to be enabled.
  */
@@ -534,6 +534,21 @@ dif_result_t dif_entropy_src_fw_override_configure(
  const dif_entropy_src_t *entropy_src,
  dif_entropy_src_fw_override_config_t config, dif_toggle_t enabled);
 
+/**
+ * Configures whether to start the entropy source's SHA3 process and be ready to
+ * accept entropy data.
+ *
+ * This is used in firmware override mode and should be enabled before writing
+ * to the override FIFO. Disable this after writing has finished to ensure the
+ * SHA3 block finishes processing and pushes the results to the `esfinal` FIFO.
+ *
+ * @param entropy_src An entropy source handle.
+ * @param enabled Whether to start the SHA3 process.
+ */
+OT_WARN_UNUSED_RESULT
+dif_result_t dif_entropy_src_fw_override_sha3_start_insert(
+ const dif_entropy_src_t *entropy_src, dif_toggle_t enabled);
+
 /**
  * Configures an entropy source health test feature with runtime information.
  *
@@ -679,7 +694,7 @@ dif_result_t dif_entropy_src_observe_fifo_nonblocking_read(
  const dif_entropy_src_t *entropy_src, uint32_t *buf, size_t *len);
 
 /**
- * Performs a write to the entropy pipeline through the observe FIFO.
+ * Performs a write to the entropy pipeline through the firmware override FIFO.
  *
  * Entropy source must be configured with firmware override and insert mode
  * enabled, otherwise the function will return `kDifError`.
@@ -691,14 +706,14 @@ dif_result_t dif_entropy_src_observe_fifo_nonblocking_read(
  * @return The result of the operation.
  */
 OT_WARN_UNUSED_RESULT
-dif_result_t dif_entropy_src_observe_fifo_write(
+dif_result_t dif_entropy_src_fw_ov_data_write(
  const dif_entropy_src_t *entropy_src, const uint32_t *buf, size_t len,
  size_t *written);
 
 /**
  * Starts conditioner operation.
  *
- * Initializes the conditioner. Use the `dif_entropy_src_observe_fifo_write()`
+ * Initializes the conditioner. Use the `dif_entropy_src_fw_ov_data_write()`
  * function to send data to the conditioner, and
  * `dif_entropy_src_conditioner_stop()` once ready to stop the conditioner
  * operation.

sw/device/lib/dif/dif_entropy_src_unittest.cc

@@ -570,12 +570,11 @@ class ObserveFifoWriteTest : public EntropySrcTest {};
 
 TEST_F(ObserveFifoWriteTest, NullArgs) {
  uint32_t buf[8] = {0};
+ EXPECT_DIF_BADARG(dif_entropy_src_fw_ov_data_write(nullptr, buf, 8, nullptr));
  EXPECT_DIF_BADARG(
- dif_entropy_src_observe_fifo_write(nullptr, buf, 8, nullptr));
+ dif_entropy_src_fw_ov_data_write(&entropy_src_, nullptr, 8, nullptr));
  EXPECT_DIF_BADARG(
- dif_entropy_src_observe_fifo_write(&entropy_src_, nullptr, 8, nullptr));
- EXPECT_DIF_BADARG(
- dif_entropy_src_observe_fifo_write(nullptr, nullptr, 8, nullptr));
+ dif_entropy_src_fw_ov_data_write(nullptr, nullptr, 8, nullptr));
 }
 
 TEST_F(ObserveFifoWriteTest, BadConfig) {
@@ -587,7 +586,7 @@ TEST_F(ObserveFifoWriteTest, BadConfig) {
  {{ENTROPY_SRC_FW_OV_CONTROL_FW_OV_ENTROPY_INSERT_OFFSET,
  kMultiBitBool4False},
  {ENTROPY_SRC_FW_OV_CONTROL_FW_OV_MODE_OFFSET, kMultiBitBool4False}});
- EXPECT_EQ(dif_entropy_src_observe_fifo_write(&entropy_src_, buf, 8, nullptr),
+ EXPECT_EQ(dif_entropy_src_fw_ov_data_write(&entropy_src_, buf, 8, nullptr),
  kDifError);
 
  // Entropy insert mode not set.
@@ -596,7 +595,7 @@ TEST_F(ObserveFifoWriteTest, BadConfig) {
  {{ENTROPY_SRC_FW_OV_CONTROL_FW_OV_ENTROPY_INSERT_OFFSET,
  kMultiBitBool4False},
  {ENTROPY_SRC_FW_OV_CONTROL_FW_OV_MODE_OFFSET, kMultiBitBool4True}});
- EXPECT_EQ(dif_entropy_src_observe_fifo_write(&entropy_src_, buf, 8, nullptr),
+ EXPECT_EQ(dif_entropy_src_fw_ov_data_write(&entropy_src_, buf, 8, nullptr),
  kDifError);
 }
 
@@ -609,7 +608,7 @@ TEST_F(ObserveFifoWriteTest, FifoFull) {
  kMultiBitBool4True},
  {ENTROPY_SRC_FW_OV_CONTROL_FW_OV_MODE_OFFSET, kMultiBitBool4True}});
  EXPECT_READ32(ENTROPY_SRC_FW_OV_WR_FIFO_FULL_REG_OFFSET, 1);
- EXPECT_EQ(dif_entropy_src_observe_fifo_write(&entropy_src_, buf, 4, &written),
+ EXPECT_EQ(dif_entropy_src_fw_ov_data_write(&entropy_src_, buf, 4, &written),
  kDifIpFifoFull);
  EXPECT_EQ(written, 0);
 }
@@ -627,7 +626,7 @@ TEST_F(ObserveFifoWriteTest, Success) {
  EXPECT_WRITE32(ENTROPY_SRC_FW_OV_WR_DATA_REG_OFFSET, i + 1);
  }
  EXPECT_DIF_OK(
- dif_entropy_src_observe_fifo_write(&entropy_src_, buf, 4, &written));
+ dif_entropy_src_fw_ov_data_write(&entropy_src_, buf, 4, &written));
  EXPECT_EQ(written, 4);
 }
 

sw/device/lib/testing/entropy_testutils.c

@@ -191,6 +191,23 @@ status_t entropy_testutils_wait_for_state(const dif_entropy_src_t *entropy_src,
  return OK_STATUS();
 }
 
+status_t entropy_testutils_drain_observe_fifo(dif_entropy_src_t *entropy_src) {
+ // This value is arbitrary, it could be 1 but since there is some
+ // overhead in dif_entropy_src_observe_fifo_nonblocking_read, it's better
+ // to read several words every time to drain the FIFO quickly.
+ const size_t kDrainCount = 32;
+ size_t len;
+ // Read from the FIFO until we get a short read which means that the FIFO was
+ // emptied.
+ do {
+ len = kDrainCount;
+ TRY(dif_entropy_src_observe_fifo_nonblocking_read(entropy_src, NULL, &len));
+ } while (len == kDrainCount);
+ TRY(dif_entropy_src_clear_fifo_overflow(entropy_src));
+
+ return OK_STATUS();
+}
+
 status_t entropy_testutils_stop_all(void) {
  const dif_entropy_src_t entropy_src = {
  .base_addr = mmio_region_from_addr(TOP_EARLGREY_ENTROPY_SRC_BASE_ADDR)};
@@ -208,6 +225,24 @@ status_t entropy_testutils_stop_all(void) {
  return OK_STATUS();
 }
 
+status_t entropy_testutils_disable_health_tests(
+ dif_entropy_src_t *entropy_src) {
+ static dif_entropy_src_test_t kHealthTest[] = {
+ kDifEntropySrcTestRepetitionCount,
+ kDifEntropySrcTestRepetitionCountSymbol,
+ kDifEntropySrcTestAdaptiveProportion, kDifEntropySrcTestBucket,
+ kDifEntropySrcTestMarkov};
+ for (size_t i = 0; i < ARRAYSIZE(kHealthTest); i++) {
+ TRY(dif_entropy_src_health_test_configure(
+ entropy_src,
+ (dif_entropy_src_health_test_config_t){.test_type = kHealthTest[i],
+ .high_threshold = 0xffffffff,
+ .low_threshold = 0}));
+ }
+
+ return OK_STATUS();
+}
+
 status_t entropy_testutils_error_check(const dif_entropy_src_t *entropy_src,
  const dif_csrng_t *csrng,
  const dif_edn_t *edn0,

sw/device/lib/testing/entropy_testutils.h

@@ -53,6 +53,13 @@ status_t entropy_testutils_fw_override_enable(dif_entropy_src_t *entropy_src,
  bool firmware_override_enable,
  bool bypass_conditioner);
 
+/**
+ * Drain the `entropy_src` FW override mode observe FIFO and clear overflow
+ * status if set.
+ */
+OT_WARN_UNUSED_RESULT
+status_t entropy_testutils_drain_observe_fifo(dif_entropy_src_t *entropy_src);
+
 /**
  * Waits for the entropy_src to reach a certain state.
  *
@@ -71,6 +78,12 @@ status_t entropy_testutils_wait_for_state(const dif_entropy_src_t *entropy_src,
 OT_WARN_UNUSED_RESULT
 status_t entropy_testutils_stop_all(void);
 
+/**
+ * Disables all entropy source health tests.
+ */
+OT_WARN_UNUSED_RESULT
+status_t entropy_testutils_disable_health_tests(dif_entropy_src_t *entropy_src);
+
 /**
  * Throws test assertion if there are any errors detected in any of the entropy
  * blocks.

sw/device/tests/BUILD

@@ -1330,10 +1330,13 @@ opentitan_test(
  "//sw/device/lib/base:memory",
  "//sw/device/lib/base:mmio",
  "//sw/device/lib/dif:base",
+ "//sw/device/lib/dif:csrng",
  "//sw/device/lib/dif:entropy_src",
+ "//sw/device/lib/dif:rv_core_ibex",
  "//sw/device/lib/runtime:log",
  "//sw/device/lib/testing:edn_testutils",
  "//sw/device/lib/testing:entropy_testutils",
+ "//sw/device/lib/testing:rv_core_ibex_testutils",
  "//sw/device/lib/testing/test_framework:ottf_main",
  ],
 )
@@ -5204,3 +5207,36 @@ opentitan_test(
  "//sw/device/lib/testing/test_framework:ottf_utils",
  ],
 )
+
+opentitan_test(
+ name = "entropy_src_fw_override_test",
+ srcs = ["entropy_src_fw_override_test.c"],
+ exec_env = dicts.add(
+ EARLGREY_TEST_ENVS,
+ EARLGREY_SILICON_OWNER_ROM_EXT_ENVS,
+ {
+ "//hw/top_earlgrey:silicon_creator": None,
+ },
+ ),
+ deps = [
+ "//hw/ip/entropy_src/data:entropy_src_regs",
+ "//hw/top_earlgrey/sw/autogen:top_earlgrey",
+ "//sw/device/lib/base:memory",
+ "//sw/device/lib/base:mmio",
+ "//sw/device/lib/dif:aes",
+ "//sw/device/lib/dif:base",
+ "//sw/device/lib/dif:csrng",
+ "//sw/device/lib/dif:entropy_src",
+ "//sw/device/lib/dif:hmac",
+ "//sw/device/lib/dif:kmac",
+ "//sw/device/lib/dif:rv_core_ibex",
+ "//sw/device/lib/runtime:log",
+ "//sw/device/lib/testing:aes_testutils",
+ "//sw/device/lib/testing:edn_testutils",
+ "//sw/device/lib/testing:entropy_testutils",
+ "//sw/device/lib/testing:hmac_testutils",
+ "//sw/device/lib/testing:kmac_testutils",
+ "//sw/device/lib/testing:rv_core_ibex_testutils",
+ "//sw/device/lib/testing/test_framework:ottf_main",
+ ],
+)

sw/device/tests/entropy_src_fw_observe_many_contiguous.c

@@ -69,26 +69,6 @@ bool entropy_src_fifo_has_overflowed(void) {
  return fifo_depth == ENTROPY_SRC_PARAM_OBSERVE_FIFO_DEPTH;
 }
 
-/**
- * Drain observe FIFO and clear overflow status if set.
- */
-static void drain_observe_fifo(void) {
- // This value is arbitrary, it could be 1 but since there is some
- // overhead in dif_entropy_src_observe_fifo_nonblocking_read, it's better
- // to read several words every time to drain the FIFO quickly.
- const size_t kDrainCount = 32;
- size_t len;
- // Read from the FIFO until we get a short read which means that the FIFO was
- // emptied.
- LOG_INFO("drain observe FIFO overflow...");
- do {
- len = kDrainCount;
- CHECK_DIF_OK(dif_entropy_src_observe_fifo_nonblocking_read(&entropy_src,
- NULL, &len));
- } while (len == kDrainCount);
- CHECK_DIF_OK(dif_entropy_src_clear_fifo_overflow(&entropy_src));
-}
-
 /**
  * Let observe FIFO overflow.
  */
@@ -107,20 +87,9 @@ static status_t entropy_config(
  edn_testutils_auto_params_build(false, /*res_itval=*/0, /*glen_val=*/0);
  // Disable the entropy complex.
  TRY(entropy_testutils_stop_all());
-
  // Disable all health tests.
- static dif_entropy_src_test_t kHealthTest[] = {
- kDifEntropySrcTestRepetitionCount,
- kDifEntropySrcTestRepetitionCountSymbol,
- kDifEntropySrcTestAdaptiveProportion, kDifEntropySrcTestBucket,
- kDifEntropySrcTestMarkov};
- for (size_t i = 0; i < ARRAYSIZE(kHealthTest); i++) {
- TRY(dif_entropy_src_health_test_configure(
- &entropy_src,
- (dif_entropy_src_health_test_config_t){.test_type = kHealthTest[i],
- .high_threshold = 0xffffffff,
- .low_threshold = 0}));
- }
+ TRY(entropy_testutils_disable_health_tests(&entropy_src));
+
  // Enable FW override.
  TRY(dif_entropy_src_fw_override_configure(
  &entropy_src,
@@ -173,7 +142,8 @@ status_t firmware_override_observe(
  uint32_t words_to_read = nr_sample_words;
  uint32_t *sample_buffer_ptr = sample_buffer;
  // Drain FIFO to make sure we get contiguous samples.
- drain_observe_fifo();
+ LOG_INFO("drain observe FIFO overflow...");
+ TRY(entropy_testutils_drain_observe_fifo(&entropy_src));
  // Collect.
  ibex_timeout_t tmo = ibex_timeout_init(timeout_usec);
  while (words_to_read > 0 && !ibex_timeout_check(&tmo)) {