tpm: Support boot measurements

Add TPM2 functions to support boot measurement. This includes
starting up the TPM, initializing/appending the event log, and
measuring the U-Boot version. Much of the code was used in the
EFI subsystem, so remove it there and use the common functions.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
For the API moving around from EFI -> u-boot core
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
For EFI testing
Tested-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>

5 files changed, 1154 insertions, 1020 deletions

diff --git a/include/efi_tcg2.h b/include/efi_tcg2.h
index b1c3abd..b21c5cb 100644
--- a/include/efi_tcg2.h
+++ b/include/efi_tcg2.h
@@ -129,50 +129,6 @@ struct efi_tcg2_boot_service_capability {
 #define BOOT_SERVICE_CAPABILITY_MIN \
 	offsetof(struct efi_tcg2_boot_service_capability, number_of_pcr_banks)
 
-#define TCG_EFI_SPEC_ID_EVENT_SIGNATURE_03 "Spec ID Event03"
-#define TCG_EFI_SPEC_ID_EVENT_SPEC_VERSION_MAJOR_TPM2 2
-#define TCG_EFI_SPEC_ID_EVENT_SPEC_VERSION_MINOR_TPM2 0
-#define TCG_EFI_SPEC_ID_EVENT_SPEC_VERSION_ERRATA_TPM2 2
-
-/**
- *  struct TCG_EfiSpecIdEventAlgorithmSize - hashing algorithm information
- *
- *  @algorithm_id:	algorithm defined in enum tpm2_algorithms
- *  @digest_size:	size of the algorithm
- */
-struct tcg_efi_spec_id_event_algorithm_size {
-	u16      algorithm_id;
-	u16      digest_size;
-} __packed;
-
-/**
- * struct TCG_EfiSpecIDEventStruct - content of the event log header
- *
- * @signature:			signature, set to Spec ID Event03
- * @platform_class:		class defined in TCG ACPI Specification
- *				Client  Common Header.
- * @spec_version_minor:		minor version
- * @spec_version_major:		major version
- * @spec_version_errata:	major version
- * @uintn_size:			size of the efi_uintn_t fields used in various
- *				data structures used in this specification.
- *				0x01 indicates u32  and 0x02  indicates u64
- * @number_of_algorithms:	hashing algorithms used in this event log
- * @digest_sizes:		array of number_of_algorithms pairs
- *				1st member defines the algorithm id
- *				2nd member defines the algorithm size
- */
-struct tcg_efi_spec_id_event {
-	u8 signature[16];
-	u32 platform_class;
-	u8 spec_version_minor;
-	u8 spec_version_major;
-	u8 spec_errata;
-	u8 uintn_size;
-	u32 number_of_algorithms;
-	struct tcg_efi_spec_id_event_algorithm_size digest_sizes[];
-} __packed;
-
 /**
  * struct tdEFI_TCG2_FINAL_EVENTS_TABLE - log entries after Get Event Log
  * @version:		version number for this structure
diff --git a/include/tpm-v2.h b/include/tpm-v2.h
index 6684033..33dd103 100644
--- a/include/tpm-v2.h
+++ b/include/tpm-v2.h
@@ -217,6 +217,50 @@ struct tcg_pcr_event2 {
 } __packed;
 
 /**
+ *  struct TCG_EfiSpecIdEventAlgorithmSize - hashing algorithm information
+ *
+ *  @algorithm_id:	algorithm defined in enum tpm2_algorithms
+ *  @digest_size:	size of the algorithm
+ */
+struct tcg_efi_spec_id_event_algorithm_size {
+	u16      algorithm_id;
+	u16      digest_size;
+} __packed;
+
+#define TCG_EFI_SPEC_ID_EVENT_SIGNATURE_03 "Spec ID Event03"
+#define TCG_EFI_SPEC_ID_EVENT_SPEC_VERSION_MAJOR_TPM2 2
+#define TCG_EFI_SPEC_ID_EVENT_SPEC_VERSION_MINOR_TPM2 0
+#define TCG_EFI_SPEC_ID_EVENT_SPEC_VERSION_ERRATA_TPM2 2
+
+/**
+ * struct TCG_EfiSpecIDEventStruct - content of the event log header
+ *
+ * @signature:			signature, set to Spec ID Event03
+ * @platform_class:		class defined in TCG ACPI Specification
+ *				Client  Common Header.
+ * @spec_version_minor:		minor version
+ * @spec_version_major:		major version
+ * @spec_version_errata:	major version
+ * @uintn_size:			size of the efi_uintn_t fields used in various
+ *				data structures used in this specification.
+ *				0x01 indicates u32  and 0x02  indicates u64
+ * @number_of_algorithms:	hashing algorithms used in this event log
+ * @digest_sizes:		array of number_of_algorithms pairs
+ *				1st member defines the algorithm id
+ *				2nd member defines the algorithm size
+ */
+struct tcg_efi_spec_id_event {
+	u8 signature[16];
+	u32 platform_class;
+	u8 spec_version_minor;
+	u8 spec_version_major;
+	u8 spec_errata;
+	u8 uintn_size;
+	u32 number_of_algorithms;
+	struct tcg_efi_spec_id_event_algorithm_size digest_sizes[];
+} __packed;
+
+/**
  * TPM2 Structure Tags for command/response buffers.
  *
  * @TPM2_ST_NO_SESSIONS: the command does not need an authentication.
@@ -342,6 +386,26 @@ enum tpm2_algorithms {
 	TPM2_ALG_SM3_256	= 0x12,
 };
 
+extern const enum tpm2_algorithms tpm2_supported_algorithms[4];
+
+static inline u16 tpm2_algorithm_to_len(enum tpm2_algorithms a)
+{
+	switch (a) {
+	case TPM2_ALG_SHA1:
+		return TPM2_SHA1_DIGEST_SIZE;
+	case TPM2_ALG_SHA256:
+		return TPM2_SHA256_DIGEST_SIZE;
+	case TPM2_ALG_SHA384:
+		return TPM2_SHA384_DIGEST_SIZE;
+	case TPM2_ALG_SHA512:
+		return TPM2_SHA512_DIGEST_SIZE;
+	default:
+		return 0;
+	}
+}
+
+#define tpm2_algorithm_to_mask(a)	(1 << (a))
+
 /* NV index attributes */
 enum tpm_index_attrs {
 	TPMA_NV_PPWRITE		= 1UL << 0,
@@ -422,6 +486,188 @@ enum {
 };
 
 /**
+ * struct tcg2_event_log - Container for managing the platform event log
+ *
+ * @log:		Address of the log
+ * @log_position:	Current entry position
+ * @log_size:		Log space available
+ * @found:		Boolean indicating if an existing log was discovered
+ */
+struct tcg2_event_log {
+	u8 *log;
+	u32 log_position;
+	u32 log_size;
+	bool found;
+};
+
+/**
+ * Create a list of digests of the supported PCR banks for a given input data
+ *
+ * @dev		TPM device
+ * @input	Data
+ * @length	Length of the data to calculate the digest
+ * @digest_list	List of digests to fill in
+ *
+ * Return: zero on success, negative errno otherwise
+ */
+int tcg2_create_digest(struct udevice *dev, const u8 *input, u32 length,
+		       struct tpml_digest_values *digest_list);
+
+/**
+ * Get the event size of the specified digests
+ *
+ * @digest_list	List of digests for the event
+ *
+ * Return: Size in bytes of the event
+ */
+u32 tcg2_event_get_size(struct tpml_digest_values *digest_list);
+
+/**
+ * tcg2_get_active_pcr_banks
+ *
+ * @dev			TPM device
+ * @active_pcr_banks	Bitmask of PCR algorithms supported
+ *
+ * Return: zero on success, negative errno otherwise
+ */
+int tcg2_get_active_pcr_banks(struct udevice *dev, u32 *active_pcr_banks);
+
+/**
+ * tcg2_log_append - Append an event to an event log
+ *
+ * @pcr_index	Index of the PCR
+ * @event_type	Type of event
+ * @digest_list List of digests to add
+ * @size	Size of event
+ * @event	Event data
+ * @log		Log buffer to append the event to
+ */
+void tcg2_log_append(u32 pcr_index, u32 event_type,
+		     struct tpml_digest_values *digest_list, u32 size,
+		     const u8 *event, u8 *log);
+
+/**
+ * Extend the PCR with specified digests
+ *
+ * @dev		TPM device
+ * @pcr_index	Index of the PCR
+ * @digest_list	List of digests to extend
+ *
+ * Return: zero on success, negative errno otherwise
+ */
+int tcg2_pcr_extend(struct udevice *dev, u32 pcr_index,
+		    struct tpml_digest_values *digest_list);
+
+/**
+ * Read the PCR into a list of digests
+ *
+ * @dev		TPM device
+ * @pcr_index	Index of the PCR
+ * @digest_list	List of digests to extend
+ *
+ * Return: zero on success, negative errno otherwise
+ */
+int tcg2_pcr_read(struct udevice *dev, u32 pcr_index,
+		  struct tpml_digest_values *digest_list);
+
+/**
+ * Measure data into the TPM PCRs and the platform event log.
+ *
+ * @dev		TPM device
+ * @log		Platform event log
+ * @pcr_index	Index of the PCR
+ * @size	Size of the data or 0 for event only
+ * @data	Pointer to the data or NULL for event only
+ * @event_type	Event log type
+ * @event_size	Size of the event
+ * @event	Pointer to the event
+ *
+ * Return: zero on success, negative errno otherwise
+ */
+int tcg2_measure_data(struct udevice *dev, struct tcg2_event_log *elog,
+		      u32 pcr_index, u32 size, const u8 *data, u32 event_type,
+		      u32 event_size, const u8 *event);
+
+#define tcg2_measure_event(dev, elog, pcr_index, event_type, size, event) \
+	tcg2_measure_data(dev, elog, pcr_index, 0, NULL, event_type, size, \
+			  event)
+
+/**
+ * Prepare the event log buffer. This function tries to discover an existing
+ * event log in memory from a previous bootloader stage. If such a log exists
+ * and the PCRs are not extended, the log is "replayed" to extend the PCRs.
+ * If no log is discovered, create the log header.
+ *
+ * @dev			TPM device
+ * @elog		Platform event log. The log pointer and log_size
+ *			members must be initialized to either 0 or to a valid
+ *			memory region, in which case any existing log
+ *			discovered will be copied to the specified memory
+ *			region.
+ * @ignore_existing_log	Boolean to indicate whether or not to ignore an
+ *			existing platform log in memory
+ *
+ * Return: zero on success, negative errno otherwise
+ */
+int tcg2_log_prepare_buffer(struct udevice *dev, struct tcg2_event_log *elog,
+			    bool ignore_existing_log);
+
+/**
+ * Begin measurements.
+ *
+ * @dev			TPM device
+ * @elog		Platform event log. The log pointer and log_size
+ *			members must be initialized to either 0 or to a valid
+ *			memory region, in which case any existing log
+ *			discovered will be copied to the specified memory
+ *			region.
+ * @ignore_existing_log Boolean to indicate whether or not to ignore an
+ *			existing platform log in memory
+ *
+ * Return: zero on success, negative errno otherwise
+ */
+int tcg2_measurement_init(struct udevice **dev, struct tcg2_event_log *elog,
+			  bool ignore_existing_log);
+
+/**
+ * Stop measurements and record separator events.
+ *
+ * @dev		TPM device
+ * @elog	Platform event log
+ * @error	Boolean to indicate whether an error ocurred or not
+ */
+void tcg2_measurement_term(struct udevice *dev, struct tcg2_event_log *elog,
+			   bool error);
+
+/**
+ * Get the platform event log address and size.
+ *
+ * @dev		TPM device
+ * @addr	Address of the log
+ * @size	Size of the log
+ *
+ * Return: zero on success, negative errno otherwise
+ */
+int tcg2_platform_get_log(struct udevice *dev, void **addr, u32 *size);
+
+/**
+ * Get the first TPM2 device found.
+ *
+ * @dev		TPM device
+ *
+ * Return: zero on success, negative errno otherwise
+ */
+int tcg2_platform_get_tpm2(struct udevice **dev);
+
+/**
+ * Platform-specific function for handling TPM startup errors
+ *
+ * @dev		TPM device
+ * @rc		The TPM response code
+ */
+void tcg2_platform_startup_error(struct udevice *dev, int rc);
+
+/**
  * Issue a TPM2_Startup command.
  *
  * @dev		TPM device
@@ -541,6 +787,19 @@ u32 tpm2_get_capability(struct udevice *dev, u32 capability, u32 property,
 			void *buf, size_t prop_count);
 
 /**
+ * tpm2_get_pcr_info() - get the supported, active PCRs and number of banks
+ *
+ * @dev:		TPM device
+ * @supported_pcr:	bitmask with the algorithms supported
+ * @active_pcr:		bitmask with the active algorithms
+ * @pcr_banks:		number of PCR banks
+ *
+ * @return 0 on success, code of operation or negative errno on failure
+ */
+int tpm2_get_pcr_info(struct udevice *dev, u32 *supported_pcr, u32 *active_pcr,
+		      u32 *pcr_banks);
+
+/**
  * Issue a TPM2_DictionaryAttackLockReset command.
  *
  * @dev		TPM device
diff --git a/lib/Kconfig b/lib/Kconfig
index 79cf9ef..bc106e2 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -431,6 +431,10 @@ config TPM
 	bool "Trusted Platform Module (TPM) Support"
 	depends on DM
 	imply DM_RNG
+	select SHA1
+	select SHA256
+	select SHA384
+	select SHA512
 	help
 	  This enables support for TPMs which can be used to provide security
 	  features for your board. The TPM can be connected via LPC or I2C
diff --git a/lib/efi_loader/efi_tcg2.c b/lib/efi_loader/efi_tcg2.c
index 7b7926a..b87c790 100644
--- a/lib/efi_loader/efi_tcg2.c
+++ b/lib/efi_loader/efi_tcg2.c
@@ -66,35 +66,6 @@ static bool tcg2_efi_app_invoked;
 static const efi_guid_t efi_guid_tcg2_protocol = EFI_TCG2_PROTOCOL_GUID;
 static const efi_guid_t efi_guid_final_events = EFI_TCG2_FINAL_EVENTS_TABLE_GUID;
 
-struct digest_info {
-	u16 hash_alg;
-	u32 hash_mask;
-	u16 hash_len;
-};
-
-static const struct digest_info hash_algo_list[] = {
-	{
-		TPM2_ALG_SHA1,
-		EFI_TCG2_BOOT_HASH_ALG_SHA1,
-		TPM2_SHA1_DIGEST_SIZE,
-	},
-	{
-		TPM2_ALG_SHA256,
-		EFI_TCG2_BOOT_HASH_ALG_SHA256,
-		TPM2_SHA256_DIGEST_SIZE,
-	},
-	{
-		TPM2_ALG_SHA384,
-		EFI_TCG2_BOOT_HASH_ALG_SHA384,
-		TPM2_SHA384_DIGEST_SIZE,
-	},
-	{
-		TPM2_ALG_SHA512,
-		EFI_TCG2_BOOT_HASH_ALG_SHA512,
-		TPM2_SHA512_DIGEST_SIZE,
-	},
-};
-
 struct variable_info {
 	const u16	*name;
 	bool		accept_empty;
@@ -113,46 +84,6 @@ static struct variable_info secure_variables[] = {
 	{u"AuditMode",		false,	1},
 };
 
-#define MAX_HASH_COUNT ARRAY_SIZE(hash_algo_list)
-
-/**
- * alg_to_mask - Get a TCG hash mask for algorithms
- *
- * @hash_alg: TCG defined algorithm
- *
- * @Return: TCG hashing algorithm bitmaps, 0 if the algorithm is not supported
- */
-static u32 alg_to_mask(u16 hash_alg)
-{
-	size_t i;
-
-	for (i = 0; i < MAX_HASH_COUNT; i++) {
-		if (hash_algo_list[i].hash_alg == hash_alg)
-			return hash_algo_list[i].hash_mask;
-	}
-
-	return 0;
-}
-
-/**
- * alg_to_len - Get a TCG hash len for algorithms
- *
- * @hash_alg: TCG defined algorithm
- *
- * @Return: len of chosen algorithm, 0 if the algorithm is not supported
- */
-static u16 alg_to_len(u16 hash_alg)
-{
-	size_t i;
-
-	for (i = 0; i < MAX_HASH_COUNT; i++) {
-		if (hash_algo_list[i].hash_alg == hash_alg)
-			return hash_algo_list[i].hash_len;
-	}
-
-	return 0;
-}
-
 static bool is_tcg2_protocol_installed(void)
 {
 	struct efi_handler *handler;
@@ -162,145 +93,6 @@ static bool is_tcg2_protocol_installed(void)
 	return ret == EFI_SUCCESS;
 }
 
-static u32 tcg_event_final_size(struct tpml_digest_values *digest_list)
-{
-	u32 len;
-	size_t i;
-
-	len = offsetof(struct tcg_pcr_event2, digests);
-	len += offsetof(struct tpml_digest_values, digests);
-	for (i = 0; i < digest_list->count; i++) {
-		u16 hash_alg = digest_list->digests[i].hash_alg;
-
-		len += offsetof(struct tpmt_ha, digest);
-		len += alg_to_len(hash_alg);
-	}
-	len += sizeof(u32); /* tcg_pcr_event2 event_size*/
-
-	return len;
-}
-
-/* tcg2_pcr_extend - Extend PCRs for a TPM2 device for a given tpml_digest_values
- *
- * @dev:		device
- * @digest_list:	list of digest algorithms to extend
- *
- * @Return: status code
- */
-static efi_status_t tcg2_pcr_extend(struct udevice *dev, u32 pcr_index,
-				    struct tpml_digest_values *digest_list)
-{
-	u32 rc;
-	size_t i;
-
-	for (i = 0; i < digest_list->count; i++) {
-		u32 alg = digest_list->digests[i].hash_alg;
-
-		rc = tpm2_pcr_extend(dev, pcr_index, alg,
-				     (u8 *)&digest_list->digests[i].digest,
-				     alg_to_len(alg));
-		if (rc) {
-			EFI_PRINT("Failed to extend PCR\n");
-			return EFI_DEVICE_ERROR;
-		}
-	}
-
-	return EFI_SUCCESS;
-}
-
-/* tcg2_pcr_read - Read PCRs for a TPM2 device for a given tpml_digest_values
- *
- * @dev:		device
- * @pcr_index:		PCR index
- * @digest_list:	list of digest algorithms to extend
- *
- * @Return: status code
- */
-static efi_status_t tcg2_pcr_read(struct udevice *dev, u32 pcr_index,
-				  struct tpml_digest_values *digest_list)
-{
-	struct tpm_chip_priv *priv;
-	unsigned int updates, pcr_select_min;
-	u32 rc;
-	size_t i;
-
-	priv = dev_get_uclass_priv(dev);
-	if (!priv)
-		return EFI_DEVICE_ERROR;
-
-	pcr_select_min = priv->pcr_select_min;
-
-	for (i = 0; i < digest_list->count; i++) {
-		u16 hash_alg = digest_list->digests[i].hash_alg;
-		u8 *digest = (u8 *)&digest_list->digests[i].digest;
-
-		rc = tpm2_pcr_read(dev, pcr_index, pcr_select_min,
-				   hash_alg, digest, alg_to_len(hash_alg),
-				   &updates);
-		if (rc) {
-			EFI_PRINT("Failed to read PCR\n");
-			return EFI_DEVICE_ERROR;
-		}
-	}
-
-	return EFI_SUCCESS;
-}
-
-/* put_event - Append an agile event to an eventlog
- *
- * @pcr_index:		PCR index
- * @event_type:		type of event added
- * @digest_list:	list of digest algorithms to add
- * @size:		size of event
- * @event:		event to add
- * @log:		log buffer to append the event
- *
- */
-static void put_event(u32 pcr_index, u32 event_type,
-		      struct tpml_digest_values *digest_list, u32 size,
-		      u8 event[], void *log)
-{
-	size_t pos;
-	size_t i;
-	u32 event_size;
-
-	/*
-	 * size refers to the length of event[] only, we need to check against
-	 * the final tcg_pcr_event2 size
-	 */
-	event_size = size + tcg_event_final_size(digest_list);
-
-	put_unaligned_le32(pcr_index, log);
-	pos = offsetof(struct tcg_pcr_event2, event_type);
-	put_unaligned_le32(event_type, (void *)((uintptr_t)log + pos));
-	pos = offsetof(struct tcg_pcr_event2, digests); /* count */
-	put_unaligned_le32(digest_list->count, (void *)((uintptr_t)log + pos));
-
-	pos += offsetof(struct tpml_digest_values, digests);
-	for (i = 0; i < digest_list->count; i++) {
-		u16 hash_alg = digest_list->digests[i].hash_alg;
-		u8 *digest = (u8 *)&digest_list->digests[i].digest;
-
-		put_unaligned_le16(hash_alg, (void *)((uintptr_t)log + pos));
-		pos += offsetof(struct tpmt_ha, digest);
-		memcpy((void *)((uintptr_t)log + pos), digest, alg_to_len(hash_alg));
-		pos += alg_to_len(hash_alg);
-	}
-
-	put_unaligned_le32(size, (void *)((uintptr_t)log + pos));
-	pos += sizeof(u32); /* tcg_pcr_event2 event_size*/
-	memcpy((void *)((uintptr_t)log + pos), event, size);
-	pos += size;
-
-	/*
-	 * make sure the calculated buffer is what we checked against
-	 * This check should never fail.  It checks the code above is
-	 * calculating the right length for the event we are adding
-	 */
-	if (pos != event_size)
-		log_err("Appending to the EventLog failed\n");
-}
-
 /* tcg2_agile_log_append - Append an agile event to an eventlog
  *
  * @pcr_index:		PCR index
@@ -317,7 +109,7 @@ static efi_status_t tcg2_agile_log_append(u32 pcr_index, u32 event_type,
 					  u32 size, u8 event[])
 {
 	void *log = (void *)((uintptr_t)event_log.buffer + event_log.pos);
-	u32 event_size = size + tcg_event_final_size(digest_list);
+	u32 event_size = size + tcg2_event_get_size(digest_list);
 	struct efi_tcg2_final_events_table *final_event;
 	efi_status_t ret = EFI_SUCCESS;
 
@@ -328,7 +120,7 @@ static efi_status_t tcg2_agile_log_append(u32 pcr_index, u32 event_type,
 			event_log.truncated = true;
 			return EFI_VOLUME_FULL;
 		}
-		put_event(pcr_index, event_type, digest_list, size, event, log);
+		tcg2_log_append(pcr_index, event_type, digest_list, size, event, log);
 		event_log.pos += event_size;
 		event_log.last_event_size = event_size;
 	}
@@ -341,7 +133,7 @@ static efi_status_t tcg2_agile_log_append(u32 pcr_index, u32 event_type,
 		return EFI_VOLUME_FULL;
 
 	log = (void *)((uintptr_t)event_log.final_buffer + event_log.final_pos);
-	put_event(pcr_index, event_type, digest_list, size, event, log);
+	tcg2_log_append(pcr_index, event_type, digest_list, size, event, log);
 
 	final_event = event_log.final_buffer;
 	final_event->number_of_events++;
@@ -351,66 +143,6 @@ static efi_status_t tcg2_agile_log_append(u32 pcr_index, u32 event_type,
 }
 
 /**
- * platform_get_tpm_device() - retrieve TPM device
- *
- * This function retrieves the udevice implementing a TPM
- *
- * This function may be overridden if special initialization is needed.
- *
- * @dev:	udevice
- * Return:	status code
- */
-__weak efi_status_t platform_get_tpm2_device(struct udevice **dev)
-{
-	for_each_tpm_device(*dev) {
-		/* Only support TPMv2 devices */
-		if (tpm_get_version(*dev) == TPM_V2)
-			return EFI_SUCCESS;
-	}
-
-	return EFI_NOT_FOUND;
-}
-
-/**
- * platform_get_eventlog() - retrieve the eventlog address and size
- *
- * This function retrieves the eventlog address and size if the underlying
- * firmware has done some measurements and passed them.
- *
- * This function may be overridden based on platform specific method of
- * passing the eventlog address and size.
- *
- * @dev:	udevice
- * @addr:	eventlog address
- * @sz:		eventlog size
- * Return:	status code
- */
-__weak efi_status_t platform_get_eventlog(struct udevice *dev, u64 *addr,
-					  u32 *sz)
-{
-	const u64 *basep;
-	const u32 *sizep;
-
-	basep = dev_read_prop(dev, "tpm_event_log_addr", NULL);
-	if (!basep)
-		return EFI_NOT_FOUND;
-
-	*addr = be64_to_cpup((__force __be64 *)basep);
-
-	sizep = dev_read_prop(dev, "tpm_event_log_size", NULL);
-	if (!sizep)
-		return EFI_NOT_FOUND;
-
-	*sz = be32_to_cpup((__force __be32 *)sizep);
-	if (*sz == 0) {
-		log_debug("event log empty\n");
-		return EFI_NOT_FOUND;
-	}
-
-	return EFI_SUCCESS;
-}
-
-/**
  * tpm2_get_max_command_size() - get the supported max command size
  *
  * @dev:		TPM device
@@ -486,238 +218,6 @@ static int tpm2_get_manufacturer_id(struct udevice *dev, u32 *manufacturer_id)
 }
 
 /**
- * tpm2_get_num_pcr() - get the number of PCRs
- *
- * @dev:		TPM device
- * @manufacturer_id:	output buffer for the number
- *
- * Return: 0 on success, -1 on error
- */
-static int tpm2_get_num_pcr(struct udevice *dev, u32 *num_pcr)
-{
-	u8 response[TPM2_RESPONSE_BUFFER_SIZE];
-	u32 ret;
-
-	memset(response, 0, sizeof(response));
-	ret = tpm2_get_capability(dev, TPM2_CAP_TPM_PROPERTIES,
-				  TPM2_PT_PCR_COUNT, response, 1);
-	if (ret)
-		return -1;
-
-	*num_pcr = get_unaligned_be32(response + properties_offset);
-	if (*num_pcr > TPM2_MAX_PCRS)
-		return -1;
-
-	return 0;
-}
-
-/**
- * is_active_pcr() - Check if a supported algorithm is active
- *
- * @dev:		TPM device
- * @selection:		struct of PCR information
- *
- * Return: true if PCR is active
- */
-static bool is_active_pcr(struct tpms_pcr_selection *selection)
-{
-	int i;
-	/*
-	 * check the pcr_select. If at least one of the PCRs supports the
-	 * algorithm add it on the active ones
-	 */
-	for (i = 0; i < selection->size_of_select; i++) {
-		if (selection->pcr_select[i])
-			return true;
-	}
-
-	return false;
-}
-
-/**
- * tpm2_get_pcr_info() - get the supported, active PCRs and number of banks
- *
- * @dev:		TPM device
- * @supported_pcr:	bitmask with the algorithms supported
- * @active_pcr:		bitmask with the active algorithms
- * @pcr_banks:		number of PCR banks
- *
- * Return: 0 on success, -1 on error
- */
-static int tpm2_get_pcr_info(struct udevice *dev, u32 *supported_pcr,
-			     u32 *active_pcr, u32 *pcr_banks)
-{
-	u8 response[TPM2_RESPONSE_BUFFER_SIZE];
-	struct tpml_pcr_selection pcrs;
-	u32 ret, num_pcr;
-	size_t i;
-	int tpm_ret;
-
-	*supported_pcr = 0;
-	*active_pcr = 0;
-	*pcr_banks = 0;
-	memset(response, 0, sizeof(response));
-	ret = tpm2_get_capability(dev, TPM2_CAP_PCRS, 0, response, 1);
-	if (ret)
-		goto out;
-
-	pcrs.count = get_unaligned_be32(response);
-	/*
-	 * We only support 5 algorithms for now so check against that
-	 * instead of TPM2_NUM_PCR_BANKS
-	 */
-	if (pcrs.count > MAX_HASH_COUNT || pcrs.count < 1)
-		goto out;
-
-	tpm_ret = tpm2_get_num_pcr(dev, &num_pcr);
-	if (tpm_ret)
-		goto out;
-
-	for (i = 0; i < pcrs.count; i++) {
-		/*
-		 * Definition of TPMS_PCR_SELECTION Structure
-		 * hash: u16
-		 * size_of_select: u8
-		 * pcr_select: u8 array
-		 *
-		 * The offsets depend on the number of the device PCRs
-		 * so we have to calculate them based on that
-		 */
-		u32 hash_offset = offsetof(struct tpml_pcr_selection, selection) +
-			i * offsetof(struct tpms_pcr_selection, pcr_select) +
-			i * ((num_pcr + 7) / 8);
-		u32 size_select_offset =
-			hash_offset + offsetof(struct tpms_pcr_selection,
-					       size_of_select);
-		u32 pcr_select_offset =
-			hash_offset + offsetof(struct tpms_pcr_selection,
-					       pcr_select);
-
-		pcrs.selection[i].hash =
-			get_unaligned_be16(response + hash_offset);
-		pcrs.selection[i].size_of_select =
-			__get_unaligned_be(response + size_select_offset);
-		if (pcrs.selection[i].size_of_select > TPM2_PCR_SELECT_MAX)
-			goto out;
-		/* copy the array of pcr_select */
-		memcpy(pcrs.selection[i].pcr_select, response + pcr_select_offset,
-		       pcrs.selection[i].size_of_select);
-	}
-
-	for (i = 0; i < pcrs.count; i++) {
-		u32 hash_mask = alg_to_mask(pcrs.selection[i].hash);
-
-		if (hash_mask) {
-			*supported_pcr |= hash_mask;
-			if (is_active_pcr(&pcrs.selection[i]))
-				*active_pcr |= hash_mask;
-		} else {
-			EFI_PRINT("Unknown algorithm %x\n", pcrs.selection[i].hash);
-		}
-	}
-
-	*pcr_banks = pcrs.count;
-
-	return 0;
-out:
-	return -1;
-}
-
-/**
- * __get_active_pcr_banks() - returns the currently active PCR banks
- *
- * @active_pcr_banks:		pointer for receiving the bitmap of currently
- *				active PCR banks
- *
- * Return:	status code
- */
-static efi_status_t __get_active_pcr_banks(u32 *active_pcr_banks)
-{
-	struct udevice *dev;
-	u32 active = 0, supported = 0, pcr_banks = 0;
-	efi_status_t ret;
-	int err;
-
-	ret = platform_get_tpm2_device(&dev);
-	if (ret != EFI_SUCCESS)
-		goto out;
-
-	err = tpm2_get_pcr_info(dev, &supported, &active, &pcr_banks);
-	if (err) {
-		ret = EFI_DEVICE_ERROR;
-		goto out;
-	}
-
-	*active_pcr_banks = active;
-
-out:
-	return ret;
-}
-
-/* tcg2_create_digest - create a list of digests of the supported PCR banks
- *			for a given memory range
- *
- * @input:		input memory
- * @length:		length of buffer to calculate the digest
- * @digest_list:	list of digests to fill in
- *
- * Return:		status code
- */
-static efi_status_t tcg2_create_digest(const u8 *input, u32 length,
-				       struct tpml_digest_values *digest_list)
-{
-	sha1_context ctx;
-	sha256_context ctx_256;
-	sha512_context ctx_512;
-	u8 final[TPM2_SHA512_DIGEST_SIZE];
-	efi_status_t ret;
-	u32 active;
-	size_t i;
-
-	ret = __get_active_pcr_banks(&active);
-	if (ret != EFI_SUCCESS)
-		return ret;
-
-	digest_list->count = 0;
-	for (i = 0; i < MAX_HASH_COUNT; i++) {
-		u16 hash_alg = hash_algo_list[i].hash_alg;
-
-		if (!(active & alg_to_mask(hash_alg)))
-			continue;
-		switch (hash_alg) {
-		case TPM2_ALG_SHA1:
-			sha1_starts(&ctx);
-			sha1_update(&ctx, input, length);
-			sha1_finish(&ctx, final);
-			break;
-		case TPM2_ALG_SHA256:
-			sha256_starts(&ctx_256);
-			sha256_update(&ctx_256, input, length);
-			sha256_finish(&ctx_256, final);
-			break;
-		case TPM2_ALG_SHA384:
-			sha384_starts(&ctx_512);
-			sha384_update(&ctx_512, input, length);
-			sha384_finish(&ctx_512, final);
-			break;
-		case TPM2_ALG_SHA512:
-			sha512_starts(&ctx_512);
-			sha512_update(&ctx_512, input, length);
-			sha512_finish(&ctx_512, final);
-			break;
-		default:
-			continue;
-		}
-		digest_list->digests[digest_list->count].hash_alg = hash_alg;
-		memcpy(&digest_list->digests[digest_list->count].digest, final,
-		       (u32)alg_to_len(hash_alg));
-		digest_list->count++;
-	}
-
-	return EFI_SUCCESS;
-}
-
-/**
  * efi_tcg2_get_capability() - protocol capability information and state information
  *
  * @this:		TCG2 protocol instance
@@ -758,7 +258,7 @@ efi_tcg2_get_capability(struct efi_tcg2_protocol *this,
 	capability->protocol_version.major = 1;
 	capability->protocol_version.minor = 1;
 
-	efi_ret = platform_get_tpm2_device(&dev);
+	efi_ret = tcg2_platform_get_tpm2(&dev);
 	if (efi_ret != EFI_SUCCESS) {
 		capability->supported_event_logs = 0;
 		capability->hash_algorithm_bitmap = 0;
@@ -854,7 +354,7 @@ efi_tcg2_get_eventlog(struct efi_tcg2_protocol *this,
 		goto out;
 	}
 
-	ret = platform_get_tpm2_device(&dev);
+	ret = tcg2_platform_get_tpm2(&dev);
 	if (ret != EFI_SUCCESS) {
 		event_log_location = NULL;
 		event_log_last_entry = NULL;
@@ -889,6 +389,7 @@ static efi_status_t tcg2_hash_pe_image(void *efi, u64 efi_size,
 	struct efi_image_regions *regs = NULL;
 	void *new_efi = NULL;
 	u8 hash[TPM2_SHA512_DIGEST_SIZE];
+	struct udevice *dev;
 	efi_status_t ret;
 	u32 active;
 	int i;
@@ -904,16 +405,20 @@ static efi_status_t tcg2_hash_pe_image(void *efi, u64 efi_size,
 		goto out;
 	}
 
-	ret = __get_active_pcr_banks(&active);
+	ret = tcg2_platform_get_tpm2(&dev);
+	if (ret != EFI_SUCCESS)
+		goto out;
+
+	ret = tcg2_get_active_pcr_banks(dev, &active);
 	if (ret != EFI_SUCCESS) {
 		goto out;
 	}
 
 	digest_list->count = 0;
-	for (i = 0; i < MAX_HASH_COUNT; i++) {
-		u16 hash_alg = hash_algo_list[i].hash_alg;
+	for (i = 0; i < ARRAY_SIZE(tpm2_supported_algorithms); i++) {
+		u16 hash_alg = tpm2_supported_algorithms[i];
 
-		if (!(active & alg_to_mask(hash_alg)))
+		if (!(active & tpm2_algorithm_to_mask(hash_alg)))
 			continue;
 		switch (hash_alg) {
 		case TPM2_ALG_SHA1:
@@ -933,7 +438,7 @@ static efi_status_t tcg2_hash_pe_image(void *efi, u64 efi_size,
 		}
 		digest_list->digests[digest_list->count].hash_alg = hash_alg;
 		memcpy(&digest_list->digests[digest_list->count].digest, hash,
-		       (u32)alg_to_len(hash_alg));
+		       (u32)tpm2_algorithm_to_len(hash_alg));
 		digest_list->count++;
 	}
 
@@ -973,7 +478,7 @@ efi_status_t tcg2_measure_pe_image(void *efi, u64 efi_size,
 	if (!is_tcg2_protocol_installed())
 		return EFI_SUCCESS;
 
-	ret = platform_get_tpm2_device(&dev);
+	ret = tcg2_platform_get_tpm2(&dev);
 	if (ret != EFI_SUCCESS)
 		return EFI_SECURITY_VIOLATION;
 
@@ -1082,7 +587,7 @@ efi_tcg2_hash_log_extend_event(struct efi_tcg2_protocol *this, u64 flags,
 		goto out;
 	}
 
-	ret = platform_get_tpm2_device(&dev);
+	ret = tcg2_platform_get_tpm2(&dev);
 	if (ret != EFI_SUCCESS)
 		goto out;
 
@@ -1117,7 +622,7 @@ efi_tcg2_hash_log_extend_event(struct efi_tcg2_protocol *this, u64 flags,
 		ret = tcg2_hash_pe_image((void *)(uintptr_t)data_to_hash,
 					 data_to_hash_len, &digest_list);
 	} else {
-		ret = tcg2_create_digest((u8 *)(uintptr_t)data_to_hash,
+		ret = tcg2_create_digest(dev, (u8 *)(uintptr_t)data_to_hash,
 					 data_to_hash_len, &digest_list);
 	}
 
@@ -1180,7 +685,7 @@ efi_tcg2_submit_command(struct efi_tcg2_protocol *this,
 		goto out;
 	}
 
-	ret = platform_get_tpm2_device(&dev);
+	ret = tcg2_platform_get_tpm2(&dev);
 	if (ret != EFI_SUCCESS)
 		goto out;
 
@@ -1209,6 +714,7 @@ static efi_status_t EFIAPI
 efi_tcg2_get_active_pcr_banks(struct efi_tcg2_protocol *this,
 			      u32 *active_pcr_banks)
 {
+	struct udevice *dev;
 	efi_status_t ret;
 
 	if (!this || !active_pcr_banks) {
@@ -1216,8 +722,12 @@ efi_tcg2_get_active_pcr_banks(struct efi_tcg2_protocol *this,
 		goto out;
 	}
 
+	ret = tcg2_platform_get_tpm2(&dev);
+	if (ret != EFI_SUCCESS)
+		goto out;
+
 	EFI_ENTRY("%p, %p", this, active_pcr_banks);
-	ret = __get_active_pcr_banks(active_pcr_banks);
+	ret = tcg2_get_active_pcr_banks(dev, active_pcr_banks);
 
 out:
 	return EFI_EXIT(ret);
@@ -1269,397 +779,6 @@ static const struct efi_tcg2_protocol efi_tcg2_protocol = {
 };
 
 /**
- * parse_event_log_header() -  Parse and verify the event log header fields
- *
- * @buffer:			Pointer to the start of the eventlog
- * @size:			Size of the eventlog
- * @pos:			Return offset of the next event in buffer right
- *				after the event header i.e specID
- *
- * Return:	status code
- */
-static efi_status_t parse_event_log_header(void *buffer, u32 size, u32 *pos)
-{
-	struct tcg_pcr_event *event_header = (struct tcg_pcr_event *)buffer;
-	int i = 0;
-
-	if (size < sizeof(*event_header))
-		return EFI_COMPROMISED_DATA;
-
-	if (get_unaligned_le32(&event_header->pcr_index) != 0 ||
-	    get_unaligned_le32(&event_header->event_type) != EV_NO_ACTION)
-		return EFI_COMPROMISED_DATA;
-
-	for (i = 0; i < sizeof(event_header->digest); i++) {
-		if (event_header->digest[i])
-			return EFI_COMPROMISED_DATA;
-	}
-
-	*pos += sizeof(*event_header);
-
-	return EFI_SUCCESS;
-}
-
-/**
- * parse_specid_event() -  Parse and verify the specID Event in the eventlog
- *
- * @dev:		udevice
- * @buffer:		Pointer to the start of the eventlog
- * @log_size:		Size of the eventlog
- * @pos:		[in] Offset of specID event in the eventlog buffer
- *			[out] Return offset of the next event in the buffer
- *			after the specID
- * @digest_list:	list of digests in the event
- *
- * Return:		status code
- * @pos			Offset in the eventlog where the specID event ends
- * @digest_list:	list of digests in the event
- */
-static efi_status_t parse_specid_event(struct udevice *dev, void *buffer,
-				       u32 log_size, u32 *pos,
-				       struct tpml_digest_values *digest_list)
-{
-	struct tcg_efi_spec_id_event *spec_event;
-	struct tcg_pcr_event *event_header = (struct tcg_pcr_event *)buffer;
-	size_t spec_event_size;
-	u32 active = 0, supported = 0, pcr_count = 0, alg_count = 0;
-	u32 spec_active = 0;
-	u16 hash_alg;
-	u8 vendor_sz;
-	int err, i;
-
-	if (*pos >= log_size || (*pos + sizeof(*spec_event)) > log_size)
-		return EFI_COMPROMISED_DATA;
-
-	/* Check specID event data */
-	spec_event = (struct tcg_efi_spec_id_event *)((uintptr_t)buffer + *pos);
-	/* Check for signature */
-	if (memcmp(spec_event->signature, TCG_EFI_SPEC_ID_EVENT_SIGNATURE_03,
-		   sizeof(TCG_EFI_SPEC_ID_EVENT_SIGNATURE_03))) {
-		log_err("specID Event: Signature mismatch\n");
-		return EFI_COMPROMISED_DATA;
-	}
-
-	if (spec_event->spec_version_minor !=
-			TCG_EFI_SPEC_ID_EVENT_SPEC_VERSION_MINOR_TPM2 ||
-	    spec_event->spec_version_major !=
-			TCG_EFI_SPEC_ID_EVENT_SPEC_VERSION_MAJOR_TPM2)
-		return EFI_COMPROMISED_DATA;
-
-	if (spec_event->number_of_algorithms > MAX_HASH_COUNT ||
-	    spec_event->number_of_algorithms < 1) {
-		log_err("specID Event: Number of algorithms incorrect\n");
-		return EFI_COMPROMISED_DATA;
-	}
-
-	alg_count = spec_event->number_of_algorithms;
-
-	err = tpm2_get_pcr_info(dev, &supported, &active, &pcr_count);
-	if (err)
-		return EFI_DEVICE_ERROR;
-
-	digest_list->count = 0;
-	/*
-	 * We have to take care that the sequence of algorithms that we record
-	 * in digest_list matches the sequence in eventlog.
-	 */
-	for (i = 0; i < alg_count; i++) {
-		hash_alg =
-		  get_unaligned_le16(&spec_event->digest_sizes[i].algorithm_id);
-
-		if (!(supported & alg_to_mask(hash_alg))) {
-			log_err("specID Event: Unsupported algorithm\n");
-			return EFI_COMPROMISED_DATA;
-		}
-		digest_list->digests[digest_list->count++].hash_alg = hash_alg;
-
-		spec_active |= alg_to_mask(hash_alg);
-	}
-
-	/*
-	 * TCG specification expects the event log to have hashes for all
-	 * active PCR's
-	 */
-	if (spec_active != active) {
-		/*
-		 * Previous stage bootloader should know all the active PCR's
-		 * and use them in the Eventlog.
-		 */
-		log_err("specID Event: All active hash alg not present\n");
-		return EFI_COMPROMISED_DATA;
-	}
-
-	/*
-	 * the size of the spec event and placement of vendor_info_size
-	 * depends on supported algoriths
-	 */
-	spec_event_size =
-		offsetof(struct tcg_efi_spec_id_event, digest_sizes) +
-		alg_count * sizeof(spec_event->digest_sizes[0]);
-
-	if (*pos + spec_event_size >= log_size)
-		return EFI_COMPROMISED_DATA;
-
-	vendor_sz = *(uint8_t *)((uintptr_t)buffer + *pos + spec_event_size);
-
-	spec_event_size += sizeof(vendor_sz) + vendor_sz;
-	*pos += spec_event_size;
-
-	if (get_unaligned_le32(&event_header->event_size) != spec_event_size) {
-		log_err("specID event: header event size mismatch\n");
-		/* Right way to handle this can be to call SetActive PCR's */
-		return EFI_COMPROMISED_DATA;
-	}
-
-	return EFI_SUCCESS;
-}
-
-/**
- * tcg2_parse_event() -  Parse the event in the eventlog
- *
- * @dev:		udevice
- * @buffer:		Pointer to the start of the eventlog
- * @log_size:		Size of the eventlog
- * @offset:		[in] Offset of the event in the eventlog buffer
- *			[out] Return offset of the next event in the buffer
- * @digest_list:	list of digests in the event
- * @pcr			Index of the PCR in the event
- *
- * Return:		status code
- */
-static efi_status_t tcg2_parse_event(struct udevice *dev, void *buffer,
-				     u32 log_size, u32 *offset,
-				     struct tpml_digest_values *digest_list,
-				     u32 *pcr)
-{
-	struct tcg_pcr_event2 *event = NULL;
-	u32 count, size, event_size;
-	size_t pos;
-
-	event_size = tcg_event_final_size(digest_list);
-	if (*offset >= log_size || *offset + event_size > log_size) {
-		log_err("Event exceeds log size\n");
-		return EFI_COMPROMISED_DATA;
-	}
-
-	event = (struct tcg_pcr_event2 *)((uintptr_t)buffer + *offset);
-	*pcr = get_unaligned_le32(&event->pcr_index);
-
-	/* get the count */
-	count = get_unaligned_le32(&event->digests.count);
-	if (count != digest_list->count)
-		return EFI_COMPROMISED_DATA;
-
-	pos = offsetof(struct tcg_pcr_event2, digests);
-	pos += offsetof(struct tpml_digest_values, digests);
-
-	for (int i = 0; i < digest_list->count; i++) {
-		u16 alg;
-		u16 hash_alg = digest_list->digests[i].hash_alg;
-		u8 *digest = (u8 *)&digest_list->digests[i].digest;
-
-		alg = get_unaligned_le16((void *)((uintptr_t)event + pos));
-
-		if (alg != hash_alg)
-			return EFI_COMPROMISED_DATA;
-
-		pos += offsetof(struct tpmt_ha, digest);
-		memcpy(digest, (void *)((uintptr_t)event + pos), alg_to_len(hash_alg));
-		pos += alg_to_len(hash_alg);
-	}
-
-	size = get_unaligned_le32((void *)((uintptr_t)event + pos));
-	event_size += size;
-	pos += sizeof(u32); /* tcg_pcr_event2 event_size*/
-	pos += size;
-
-	/* make sure the calculated buffer is what we checked against */
-	if (pos != event_size)
-		return EFI_COMPROMISED_DATA;
-
-	if (pos > log_size)
-		return EFI_COMPROMISED_DATA;
-
-	*offset += pos;
-
-	return EFI_SUCCESS;
-}
-
-/**
- * tcg2_get_fw_eventlog() -  Get the eventlog address and size
- *
- * If the previous firmware has passed some eventlog, this function get it's
- * location and check for it's validity.
- *
- * @dev:		udevice
- * @log_buffer:		eventlog address
- * @log_sz:		eventlog size
- *
- * Return:	status code
- */
-static efi_status_t tcg2_get_fw_eventlog(struct udevice *dev, void *log_buffer,
-					 size_t *log_sz)
-{
-	struct tpml_digest_values digest_list;
-	void *buffer;
-	efi_status_t ret;
-	u32 pcr, pos;
-	u64 base;
-	u32 sz;
-	bool extend_pcr = false;
-	int i;
-
-	ret = platform_get_eventlog(dev, &base, &sz);
-	if (ret != EFI_SUCCESS)
-		return ret;
-
-	if (sz > TPM2_EVENT_LOG_SIZE)
-		return EFI_VOLUME_FULL;
-
-	buffer = (void *)(uintptr_t)base;
-	pos = 0;
-	/* Parse the eventlog to check for its validity */
-	ret = parse_event_log_header(buffer, sz, &pos);
-	if (ret)
-		return ret;
-
-	ret = parse_specid_event(dev, buffer, sz, &pos, &digest_list);
-	if (ret) {
-		log_err("Error parsing SPEC ID Event\n");
-		return ret;
-	}
-
-	ret = tcg2_pcr_read(dev, 0, &digest_list);
-	if (ret) {
-		log_err("Error reading PCR 0\n");
-		return ret;
-	}
-
-	/*
-	 * If PCR0 is 0, previous firmware didn't have the capability
-	 * to extend the PCR. In this scenario, extend the PCR as
-	 * the eventlog is parsed.
-	 */
-	for (i = 0; i < digest_list.count; i++) {
-		u8 hash_buf[TPM2_SHA512_DIGEST_SIZE] = { 0 };
-		u16 hash_alg = digest_list.digests[i].hash_alg;
-
-		if (!memcmp((u8 *)&digest_list.digests[i].digest, hash_buf,
-			    alg_to_len(hash_alg)))
-			extend_pcr = true;
-	}
-
-	while (pos < sz) {
-		ret = tcg2_parse_event(dev, buffer, sz, &pos, &digest_list,
-				       &pcr);
-		if (ret) {
-			log_err("Error parsing event\n");
-			return ret;
-		}
-		if (extend_pcr) {
-			ret = tcg2_pcr_extend(dev, pcr, &digest_list);
-			if (ret != EFI_SUCCESS) {
-				log_err("Error in extending PCR\n");
-				return ret;
-			}
-
-			/* Clear the digest for next event */
-			for (i = 0; i < digest_list.count; i++) {
-				u16 hash_alg = digest_list.digests[i].hash_alg;
-				u8 *digest =
-				   (u8 *)&digest_list.digests[i].digest;
-
-				memset(digest, 0, alg_to_len(hash_alg));
-			}
-		}
-	}
-
-	memcpy(log_buffer, buffer, sz);
-	*log_sz = sz;
-
-	return ret;
-}
-
-/**
- * create_specid_event() - Create the first event in the eventlog
- *
- * @dev:			tpm device
- * @event_header:		Pointer to the final event header
- * @event_size:			final spec event size
- *
- * Return:	status code
- */
-static efi_status_t create_specid_event(struct udevice *dev, void *buffer,
-					size_t *event_size)
-{
-	struct tcg_efi_spec_id_event *spec_event;
-	size_t spec_event_size;
-	efi_status_t ret = EFI_DEVICE_ERROR;
-	u32 active = 0, supported = 0, pcr_count = 0, alg_count = 0;
-	int err;
-	size_t i;
-
-	/*
-	 * Create Spec event. This needs to be the first event in the log
-	 * according to the TCG EFI protocol spec
-	 */
-
-	/* Setup specID event data */
-	spec_event = (struct tcg_efi_spec_id_event *)buffer;
-	memcpy(spec_event->signature, TCG_EFI_SPEC_ID_EVENT_SIGNATURE_03,
-	       sizeof(spec_event->signature));
-	put_unaligned_le32(0, &spec_event->platform_class); /* type client */
-	spec_event->spec_version_minor =
-		TCG_EFI_SPEC_ID_EVENT_SPEC_VERSION_MINOR_TPM2;
-	spec_event->spec_version_major =
-		TCG_EFI_SPEC_ID_EVENT_SPEC_VERSION_MAJOR_TPM2;
-	spec_event->spec_errata =
-		TCG_EFI_SPEC_ID_EVENT_SPEC_VERSION_ERRATA_TPM2;
-	spec_event->uintn_size = sizeof(efi_uintn_t) / sizeof(u32);
-
-	err = tpm2_get_pcr_info(dev, &supported, &active, &pcr_count);
-
-	if (err)
-		goto out;
-
-	for (i = 0; i < pcr_count; i++) {
-		u16 hash_alg = hash_algo_list[i].hash_alg;
-		u16 hash_len = hash_algo_list[i].hash_len;
-
-		if (active & alg_to_mask(hash_alg)) {
-			put_unaligned_le16(hash_alg,
-					   &spec_event->digest_sizes[alg_count].algorithm_id);
-			put_unaligned_le16(hash_len,
-					   &spec_event->digest_sizes[alg_count].digest_size);
-			alg_count++;
-		}
-	}
-
-	spec_event->number_of_algorithms = alg_count;
-	if (spec_event->number_of_algorithms > MAX_HASH_COUNT ||
-	    spec_event->number_of_algorithms < 1)
-		goto out;
-
-	/*
-	 * the size of the spec event and placement of vendor_info_size
-	 * depends on supported algoriths
-	 */
-	spec_event_size =
-		offsetof(struct tcg_efi_spec_id_event, digest_sizes) +
-		spec_event->number_of_algorithms * sizeof(spec_event->digest_sizes[0]);
-	/* no vendor info for us */
-	memset(buffer + spec_event_size, 0, 1);
-	/* add a byte for vendor_info_size in the spec event */
-	spec_event_size += 1;
-	*event_size = spec_event_size;
-
-	return EFI_SUCCESS;
-
-out:
-	return ret;
-}
-
-/**
  * tcg2_uninit - remove the final event table and free efi memory on failures
  */
 void tcg2_uninit(void)
@@ -1720,7 +839,7 @@ out:
 }
 
 /**
- * tcg2_measure_event() - common function to add event log and extend PCR
+ * measure_event() - common function to add event log and extend PCR
  *
  * @dev:		TPM device
  * @pcr_index:		PCR index
@@ -1730,14 +849,13 @@ out:
  *
  * Return:	status code
  */
-static efi_status_t
-tcg2_measure_event(struct udevice *dev, u32 pcr_index, u32 event_type,
-		   u32 size, u8 event[])
+static efi_status_t measure_event(struct udevice *dev, u32 pcr_index,
+				  u32 event_type, u32 size, u8 event[])
 {
 	struct tpml_digest_values digest_list;
 	efi_status_t ret;
 
-	ret = tcg2_create_digest(event, size, &digest_list);
+	ret = tcg2_create_digest(dev, event, size, &digest_list);
 	if (ret != EFI_SUCCESS)
 		goto out;
 
@@ -1764,9 +882,8 @@ static efi_status_t efi_append_scrtm_version(struct udevice *dev)
 {
 	efi_status_t ret;
 
-	ret = tcg2_measure_event(dev, 0, EV_S_CRTM_VERSION,
-				 strlen(version_string) + 1,
-				 (u8 *)version_string);
+	ret = measure_event(dev, 0, EV_S_CRTM_VERSION,
+			    strlen(version_string) + 1, (u8 *)version_string);
 
 	return ret;
 }
@@ -1782,12 +899,11 @@ static efi_status_t efi_init_event_log(void)
 	 * vendor_info_size is currently set to 0, we need to change the length
 	 * and allocate the flexible array member if this changes
 	 */
-	struct tcg_pcr_event *event_header = NULL;
+	struct tcg2_event_log elog;
 	struct udevice *dev;
-	size_t spec_event_size;
 	efi_status_t ret;
 
-	ret = platform_get_tpm2_device(&dev);
+	ret = tcg2_platform_get_tpm2(&dev);
 	if (ret != EFI_SUCCESS)
 		return ret;
 
@@ -1806,7 +922,6 @@ static efi_status_t efi_init_event_log(void)
 	 * The log header is defined to be in SHA1 event log entry format.
 	 * Setup event header
 	 */
-	event_header =  (struct tcg_pcr_event *)event_log.buffer;
 	event_log.pos = 0;
 	event_log.last_event_size = 0;
 	event_log.get_event_called = false;
@@ -1817,34 +932,20 @@ static efi_status_t efi_init_event_log(void)
 	 * Check if earlier firmware have passed any eventlog. Different
 	 * platforms can use different ways to do so.
 	 */
-	ret = tcg2_get_fw_eventlog(dev, event_log.buffer, &event_log.pos);
+	elog.log = event_log.buffer;
+	elog.log_size = TPM2_EVENT_LOG_SIZE;
+	ret = tcg2_log_prepare_buffer(dev, &elog, false);
+	if (ret != EFI_SUCCESS)
+		goto free_pool;
+
+	event_log.pos = elog.log_position;
+
 	/*
-	 * If earlier firmware hasn't passed any eventlog, go ahead and
-	 * create the eventlog header.
+	 * Add SCRTM version to the log if previous firmmware
+	 * doesn't pass an eventlog.
 	 */
-	if (ret == EFI_NOT_FOUND) {
-		put_unaligned_le32(0, &event_header->pcr_index);
-		put_unaligned_le32(EV_NO_ACTION, &event_header->event_type);
-		memset(&event_header->digest, 0, sizeof(event_header->digest));
-		ret = create_specid_event(dev,
-					  (void *)((uintptr_t)event_log.buffer +
-						   sizeof(*event_header)),
-					  &spec_event_size);
-		if (ret != EFI_SUCCESS)
-			goto free_pool;
-		put_unaligned_le32(spec_event_size, &event_header->event_size);
-		event_log.pos = spec_event_size + sizeof(*event_header);
-		event_log.last_event_size = event_log.pos;
-
-		/*
-		 * Add SCRTM version to the log if previous firmmware
-		 * doesn't pass an eventlog.
-		 */
+	if (!elog.found)
 		ret = efi_append_scrtm_version(dev);
-	}
-
-	if (ret != EFI_SUCCESS)
-		goto free_pool;
 
 	ret = create_final_event();
 	if (ret != EFI_SUCCESS)
@@ -1897,8 +998,8 @@ static efi_status_t tcg2_measure_variable(struct udevice *dev, u32 pcr_index,
 		memcpy((u16 *)event->unicode_name + event->unicode_name_length,
 		       data, data_size);
 	}
-	ret = tcg2_measure_event(dev, pcr_index, event_type, event_size,
-				 (u8 *)event);
+	ret = measure_event(dev, pcr_index, event_type, event_size,
+			    (u8 *)event);
 	free(event);
 	return ret;
 }
@@ -2009,8 +1110,8 @@ tcg2_measure_smbios(struct udevice *dev,
 
 	smbios_prepare_measurement(entry, smbios_copy);
 
-	ret = tcg2_measure_event(dev, 1, EV_EFI_HANDOFF_TABLES2, event_size,
-				 (u8 *)event);
+	ret = measure_event(dev, 1, EV_EFI_HANDOFF_TABLES2, event_size,
+			    (u8 *)event);
 	if (ret != EFI_SUCCESS)
 		goto out;
 
@@ -2161,7 +1262,7 @@ tcg2_measure_gpt_data(struct udevice *dev,
 		gpt_e = (gpt_entry *)((u8 *)gpt_e + gpt_h->sizeof_partition_entry);
 	}
 
-	ret = tcg2_measure_event(dev, 5, EV_EFI_GPT_EVENT, event_size, (u8 *)event);
+	ret = measure_event(dev, 5, EV_EFI_GPT_EVENT, event_size, (u8 *)event);
 
 out2:
 	free(gpt_h);
@@ -2215,7 +1316,7 @@ efi_status_t efi_tcg2_measure_dtb(void *dtb)
 	if (!is_tcg2_protocol_installed())
 		return EFI_SUCCESS;
 
-	ret = platform_get_tpm2_device(&dev);
+	ret = tcg2_platform_get_tpm2(&dev);
 	if (ret != EFI_SUCCESS)
 		return EFI_SECURITY_VIOLATION;
 
@@ -2240,7 +1341,7 @@ efi_status_t efi_tcg2_measure_dtb(void *dtb)
 	sha256_update(&hash_ctx, (u8 *)dtb + fdt_off_mem_rsvmap(dtb), rsvmap_size);
 	sha256_finish(&hash_ctx, blob->data + blob->blob_description_size);
 
-	ret = tcg2_measure_event(dev, 0, EV_POST_CODE, event_size, (u8 *)blob);
+	ret = measure_event(dev, 0, EV_POST_CODE, event_size, (u8 *)blob);
 
 	free(blob);
 	return ret;
@@ -2265,7 +1366,7 @@ efi_status_t efi_tcg2_measure_efi_app_invocation(struct efi_loaded_image_obj *ha
 	if (tcg2_efi_app_invoked)
 		return EFI_SUCCESS;
 
-	ret = platform_get_tpm2_device(&dev);
+	ret = tcg2_platform_get_tpm2(&dev);
 	if (ret != EFI_SUCCESS)
 		return EFI_SECURITY_VIOLATION;
 
@@ -2273,9 +1374,9 @@ efi_status_t efi_tcg2_measure_efi_app_invocation(struct efi_loaded_image_obj *ha
 	if (ret != EFI_SUCCESS)
 		goto out;
 
-	ret = tcg2_measure_event(dev, 4, EV_EFI_ACTION,
-				 strlen(EFI_CALLING_EFI_APPLICATION),
-				 (u8 *)EFI_CALLING_EFI_APPLICATION);
+	ret = measure_event(dev, 4, EV_EFI_ACTION,
+			    strlen(EFI_CALLING_EFI_APPLICATION),
+			    (u8 *)EFI_CALLING_EFI_APPLICATION);
 	if (ret != EFI_SUCCESS)
 		goto out;
 
@@ -2291,8 +1392,8 @@ efi_status_t efi_tcg2_measure_efi_app_invocation(struct efi_loaded_image_obj *ha
 		goto out;
 
 	for (pcr_index = 0; pcr_index <= 7; pcr_index++) {
-		ret = tcg2_measure_event(dev, pcr_index, EV_SEPARATOR,
-					 sizeof(event), (u8 *)&event);
+		ret = measure_event(dev, pcr_index, EV_SEPARATOR,
+				    sizeof(event), (u8 *)&event);
 		if (ret != EFI_SUCCESS)
 			goto out;
 	}
@@ -2315,13 +1416,13 @@ efi_status_t efi_tcg2_measure_efi_app_exit(void)
 	if (!is_tcg2_protocol_installed())
 		return EFI_SUCCESS;
 
-	ret = platform_get_tpm2_device(&dev);
+	ret = tcg2_platform_get_tpm2(&dev);
 	if (ret != EFI_SUCCESS)
 		return ret;
 
-	ret = tcg2_measure_event(dev, 4, EV_EFI_ACTION,
-				 strlen(EFI_RETURNING_FROM_EFI_APPLICATION),
-				 (u8 *)EFI_RETURNING_FROM_EFI_APPLICATION);
+	ret = measure_event(dev, 4, EV_EFI_ACTION,
+			    strlen(EFI_RETURNING_FROM_EFI_APPLICATION),
+			    (u8 *)EFI_RETURNING_FROM_EFI_APPLICATION);
 	return ret;
 }
 
@@ -2346,19 +1447,19 @@ efi_tcg2_notify_exit_boot_services(struct efi_event *event, void *context)
 		goto out;
 	}
 
-	ret = platform_get_tpm2_device(&dev);
+	ret = tcg2_platform_get_tpm2(&dev);
 	if (ret != EFI_SUCCESS)
 		goto out;
 
-	ret = tcg2_measure_event(dev, 5, EV_EFI_ACTION,
-				 strlen(EFI_EXIT_BOOT_SERVICES_INVOCATION),
-				 (u8 *)EFI_EXIT_BOOT_SERVICES_INVOCATION);
+	ret = measure_event(dev, 5, EV_EFI_ACTION,
+			    strlen(EFI_EXIT_BOOT_SERVICES_INVOCATION),
+			    (u8 *)EFI_EXIT_BOOT_SERVICES_INVOCATION);
 	if (ret != EFI_SUCCESS)
 		goto out;
 
-	ret = tcg2_measure_event(dev, 5, EV_EFI_ACTION,
-				 strlen(EFI_EXIT_BOOT_SERVICES_SUCCEEDED),
-				 (u8 *)EFI_EXIT_BOOT_SERVICES_SUCCEEDED);
+	ret = measure_event(dev, 5, EV_EFI_ACTION,
+			    strlen(EFI_EXIT_BOOT_SERVICES_SUCCEEDED),
+			    (u8 *)EFI_EXIT_BOOT_SERVICES_SUCCEEDED);
 
 out:
 	EFI_EXIT(ret);
@@ -2378,19 +1479,19 @@ efi_status_t efi_tcg2_notify_exit_boot_services_failed(void)
 	if (!is_tcg2_protocol_installed())
 		return EFI_SUCCESS;
 
-	ret = platform_get_tpm2_device(&dev);
+	ret = tcg2_platform_get_tpm2(&dev);
 	if (ret != EFI_SUCCESS)
 		goto out;
 
-	ret = tcg2_measure_event(dev, 5, EV_EFI_ACTION,
-				 strlen(EFI_EXIT_BOOT_SERVICES_INVOCATION),
-				 (u8 *)EFI_EXIT_BOOT_SERVICES_INVOCATION);
+	ret = measure_event(dev, 5, EV_EFI_ACTION,
+			    strlen(EFI_EXIT_BOOT_SERVICES_INVOCATION),
+			    (u8 *)EFI_EXIT_BOOT_SERVICES_INVOCATION);
 	if (ret != EFI_SUCCESS)
 		goto out;
 
-	ret = tcg2_measure_event(dev, 5, EV_EFI_ACTION,
-				 strlen(EFI_EXIT_BOOT_SERVICES_FAILED),
-				 (u8 *)EFI_EXIT_BOOT_SERVICES_FAILED);
+	ret = measure_event(dev, 5, EV_EFI_ACTION,
+			    strlen(EFI_EXIT_BOOT_SERVICES_FAILED),
+			    (u8 *)EFI_EXIT_BOOT_SERVICES_FAILED);
 
 out:
 	return ret;
@@ -2460,7 +1561,7 @@ efi_status_t efi_tcg2_do_initial_measurement(void)
 	if (!is_tcg2_protocol_installed())
 		return EFI_SUCCESS;
 
-	ret = platform_get_tpm2_device(&dev);
+	ret = tcg2_platform_get_tpm2(&dev);
 	if (ret != EFI_SUCCESS)
 		return EFI_SECURITY_VIOLATION;
 
@@ -2486,7 +1587,7 @@ efi_status_t efi_tcg2_register(void)
 	struct efi_event *event;
 	u32 err;
 
-	ret = platform_get_tpm2_device(&dev);
+	ret = tcg2_platform_get_tpm2(&dev);
 	if (ret != EFI_SUCCESS) {
 		log_warning("Missing TPMv2 device for EFI_TCG_PROTOCOL\n");
 		return EFI_SUCCESS;
diff --git a/lib/tpm-v2.c b/lib/tpm-v2.c
index 9ab5b46..bd0fb07 100644
--- a/lib/tpm-v2.c
+++ b/lib/tpm-v2.c
@@ -1,16 +1,705 @@
 // SPDX-License-Identifier: GPL-2.0+
 /*
+ * Copyright (c) 2023 Linaro Limited
  * Copyright (c) 2018 Bootlin
  * Author: Miquel Raynal <miquel.raynal@bootlin.com>
  */
 
 #include <common.h>
 #include <dm.h>
+#include <dm/of_access.h>
+#include <tpm_api.h>
 #include <tpm-common.h>
 #include <tpm-v2.h>
+#include <u-boot/sha1.h>
+#include <u-boot/sha256.h>
+#include <u-boot/sha512.h>
+#include <version_string.h>
+#include <asm/io.h>
 #include <linux/bitops.h>
+#include <linux/unaligned/be_byteshift.h>
+#include <linux/unaligned/generic.h>
+#include <linux/unaligned/le_byteshift.h>
+
 #include "tpm-utils.h"
 
+const enum tpm2_algorithms tpm2_supported_algorithms[4] = {
+	TPM2_ALG_SHA1,
+	TPM2_ALG_SHA256,
+	TPM2_ALG_SHA384,
+	TPM2_ALG_SHA512,
+};
+
+int tcg2_get_active_pcr_banks(struct udevice *dev, u32 *active_pcr_banks)
+{
+	u32 supported = 0;
+	u32 pcr_banks = 0;
+	u32 active = 0;
+	int rc;
+
+	rc = tpm2_get_pcr_info(dev, &supported, &active, &pcr_banks);
+	if (rc)
+		return rc;
+
+	*active_pcr_banks = active;
+
+	return 0;
+}
+
+u32 tcg2_event_get_size(struct tpml_digest_values *digest_list)
+{
+	u32 len;
+	size_t i;
+
+	len = offsetof(struct tcg_pcr_event2, digests);
+	len += offsetof(struct tpml_digest_values, digests);
+	for (i = 0; i < digest_list->count; ++i) {
+		u16 l = tpm2_algorithm_to_len(digest_list->digests[i].hash_alg);
+
+		if (!l)
+			continue;
+
+		len += l + offsetof(struct tpmt_ha, digest);
+	}
+	len += sizeof(u32);
+
+	return len;
+}
+
+int tcg2_create_digest(struct udevice *dev, const u8 *input, u32 length,
+		       struct tpml_digest_values *digest_list)
+{
+	u8 final[sizeof(union tpmu_ha)];
+	sha256_context ctx_256;
+	sha512_context ctx_512;
+	sha1_context ctx;
+	u32 active;
+	size_t i;
+	u32 len;
+	int rc;
+
+	rc = tcg2_get_active_pcr_banks(dev, &active);
+	if (rc)
+		return rc;
+
+	digest_list->count = 0;
+	for (i = 0; i < ARRAY_SIZE(tpm2_supported_algorithms); ++i) {
+		u32 mask =
+			tpm2_algorithm_to_mask(tpm2_supported_algorithms[i]);
+
+		if (!(active & mask))
+			continue;
+
+		switch (tpm2_supported_algorithms[i]) {
+		case TPM2_ALG_SHA1:
+			sha1_starts(&ctx);
+			sha1_update(&ctx, input, length);
+			sha1_finish(&ctx, final);
+			len = TPM2_SHA1_DIGEST_SIZE;
+			break;
+		case TPM2_ALG_SHA256:
+			sha256_starts(&ctx_256);
+			sha256_update(&ctx_256, input, length);
+			sha256_finish(&ctx_256, final);
+			len = TPM2_SHA256_DIGEST_SIZE;
+			break;
+		case TPM2_ALG_SHA384:
+			sha384_starts(&ctx_512);
+			sha384_update(&ctx_512, input, length);
+			sha384_finish(&ctx_512, final);
+			len = TPM2_SHA384_DIGEST_SIZE;
+			break;
+		case TPM2_ALG_SHA512:
+			sha512_starts(&ctx_512);
+			sha512_update(&ctx_512, input, length);
+			sha512_finish(&ctx_512, final);
+			len = TPM2_SHA512_DIGEST_SIZE;
+			break;
+		default:
+			printf("%s: unsupported algorithm %x\n", __func__,
+			       tpm2_supported_algorithms[i]);
+			continue;
+		}
+
+		digest_list->digests[digest_list->count].hash_alg =
+			tpm2_supported_algorithms[i];
+		memcpy(&digest_list->digests[digest_list->count].digest, final,
+		       len);
+		digest_list->count++;
+	}
+
+	return 0;
+}
+
+void tcg2_log_append(u32 pcr_index, u32 event_type,
+		     struct tpml_digest_values *digest_list, u32 size,
+		     const u8 *event, u8 *log)
+{
+	size_t len;
+	size_t pos;
+	u32 i;
+
+	pos = offsetof(struct tcg_pcr_event2, pcr_index);
+	put_unaligned_le32(pcr_index, log);
+	pos = offsetof(struct tcg_pcr_event2, event_type);
+	put_unaligned_le32(event_type, log + pos);
+	pos = offsetof(struct tcg_pcr_event2, digests) +
+		offsetof(struct tpml_digest_values, count);
+	put_unaligned_le32(digest_list->count, log + pos);
+
+	pos = offsetof(struct tcg_pcr_event2, digests) +
+		offsetof(struct tpml_digest_values, digests);
+	for (i = 0; i < digest_list->count; ++i) {
+		u16 hash_alg = digest_list->digests[i].hash_alg;
+
+		len = tpm2_algorithm_to_len(hash_alg);
+		if (!len)
+			continue;
+
+		pos += offsetof(struct tpmt_ha, hash_alg);
+		put_unaligned_le16(hash_alg, log + pos);
+		pos += offsetof(struct tpmt_ha, digest);
+		memcpy(log + pos, (u8 *)&digest_list->digests[i].digest, len);
+		pos += len;
+	}
+
+	put_unaligned_le32(size, log + pos);
+	pos += sizeof(u32);
+	memcpy(log + pos, event, size);
+}
+
+static int tcg2_log_append_check(struct tcg2_event_log *elog, u32 pcr_index,
+				 u32 event_type,
+				 struct tpml_digest_values *digest_list,
+				 u32 size, const u8 *event)
+{
+	u32 event_size;
+	u8 *log;
+
+	event_size = size + tcg2_event_get_size(digest_list);
+	if (elog->log_position + event_size > elog->log_size) {
+		printf("%s: log too large: %u + %u > %u\n", __func__,
+		       elog->log_position, event_size, elog->log_size);
+		return -ENOBUFS;
+	}
+
+	log = elog->log + elog->log_position;
+	elog->log_position += event_size;
+
+	tcg2_log_append(pcr_index, event_type, digest_list, size, event, log);
+
+	return 0;
+}
+
+static int tcg2_log_init(struct udevice *dev, struct tcg2_event_log *elog)
+{
+	struct tcg_efi_spec_id_event *ev;
+	struct tcg_pcr_event *log;
+	u32 event_size;
+	u32 count = 0;
+	u32 log_size;
+	u32 active;
+	u32 mask;
+	size_t i;
+	u16 len;
+	int rc;
+
+	rc = tcg2_get_active_pcr_banks(dev, &active);
+	if (rc)
+		return rc;
+
+	event_size = offsetof(struct tcg_efi_spec_id_event, digest_sizes);
+	for (i = 0; i < ARRAY_SIZE(tpm2_supported_algorithms); ++i) {
+		mask = tpm2_algorithm_to_mask(tpm2_supported_algorithms[i]);
+
+		if (!(active & mask))
+			continue;
+
+		switch (tpm2_supported_algorithms[i]) {
+		case TPM2_ALG_SHA1:
+		case TPM2_ALG_SHA256:
+		case TPM2_ALG_SHA384:
+		case TPM2_ALG_SHA512:
+			count++;
+			break;
+		default:
+			continue;
+		}
+	}
+
+	event_size += 1 +
+		(sizeof(struct tcg_efi_spec_id_event_algorithm_size) * count);
+	log_size = offsetof(struct tcg_pcr_event, event) + event_size;
+
+	if (log_size > elog->log_size) {
+		printf("%s: log too large: %u > %u\n", __func__, log_size,
+		       elog->log_size);
+		return -ENOBUFS;
+	}
+
+	log = (struct tcg_pcr_event *)elog->log;
+	put_unaligned_le32(0, &log->pcr_index);
+	put_unaligned_le32(EV_NO_ACTION, &log->event_type);
+	memset(&log->digest, 0, sizeof(log->digest));
+	put_unaligned_le32(event_size, &log->event_size);
+
+	ev = (struct tcg_efi_spec_id_event *)log->event;
+	strlcpy((char *)ev->signature, TCG_EFI_SPEC_ID_EVENT_SIGNATURE_03,
+		sizeof(ev->signature));
+	put_unaligned_le32(0, &ev->platform_class);
+	ev->spec_version_minor = TCG_EFI_SPEC_ID_EVENT_SPEC_VERSION_MINOR_TPM2;
+	ev->spec_version_major = TCG_EFI_SPEC_ID_EVENT_SPEC_VERSION_MAJOR_TPM2;
+	ev->spec_errata = TCG_EFI_SPEC_ID_EVENT_SPEC_VERSION_ERRATA_TPM2;
+	ev->uintn_size = sizeof(size_t) / sizeof(u32);
+	put_unaligned_le32(count, &ev->number_of_algorithms);
+
+	count = 0;
+	for (i = 0; i < ARRAY_SIZE(tpm2_supported_algorithms); ++i) {
+		mask = tpm2_algorithm_to_mask(tpm2_supported_algorithms[i]);
+
+		if (!(active & mask))
+			continue;
+
+		len = tpm2_algorithm_to_len(tpm2_supported_algorithms[i]);
+		if (!len)
+			continue;
+
+		put_unaligned_le16(tpm2_supported_algorithms[i],
+				   &ev->digest_sizes[count].algorithm_id);
+		put_unaligned_le16(len, &ev->digest_sizes[count].digest_size);
+		count++;
+	}
+
+	*((u8 *)ev + (event_size - 1)) = 0;
+	elog->log_position = log_size;
+
+	return 0;
+}
+
+static int tcg2_replay_eventlog(struct tcg2_event_log *elog,
+				struct udevice *dev,
+				struct tpml_digest_values *digest_list,
+				u32 log_position)
+{
+	const u32 offset = offsetof(struct tcg_pcr_event2, digests) +
+		offsetof(struct tpml_digest_values, digests);
+	u32 event_size;
+	u32 count;
+	u16 algo;
+	u32 pcr;
+	u32 pos;
+	u16 len;
+	u8 *log;
+	int rc;
+	u32 i;
+
+	while (log_position + offset < elog->log_size) {
+		log = elog->log + log_position;
+
+		pos = offsetof(struct tcg_pcr_event2, pcr_index);
+		pcr = get_unaligned_le32(log + pos);
+		pos = offsetof(struct tcg_pcr_event2, event_type);
+		if (!get_unaligned_le32(log + pos))
+			return 0;
+
+		pos = offsetof(struct tcg_pcr_event2, digests) +
+			offsetof(struct tpml_digest_values, count);
+		count = get_unaligned_le32(log + pos);
+		if (count > ARRAY_SIZE(tpm2_supported_algorithms) ||
+		    (digest_list->count && digest_list->count != count))
+			return 0;
+
+		pos = offsetof(struct tcg_pcr_event2, digests) +
+			offsetof(struct tpml_digest_values, digests);
+		for (i = 0; i < count; ++i) {
+			pos += offsetof(struct tpmt_ha, hash_alg);
+			if (log_position + pos + sizeof(u16) >= elog->log_size)
+				return 0;
+
+			algo = get_unaligned_le16(log + pos);
+			pos += offsetof(struct tpmt_ha, digest);
+			switch (algo) {
+			case TPM2_ALG_SHA1:
+			case TPM2_ALG_SHA256:
+			case TPM2_ALG_SHA384:
+			case TPM2_ALG_SHA512:
+				len = tpm2_algorithm_to_len(algo);
+				break;
+			default:
+				return 0;
+			}
+
+			if (digest_list->count) {
+				if (algo != digest_list->digests[i].hash_alg ||
+				    log_position + pos + len >= elog->log_size)
+					return 0;
+
+				memcpy(digest_list->digests[i].digest.sha512,
+				       log + pos, len);
+			}
+
+			pos += len;
+		}
+
+		if (log_position + pos + sizeof(u32) >= elog->log_size)
+			return 0;
+
+		event_size = get_unaligned_le32(log + pos);
+		pos += event_size + sizeof(u32);
+		if (log_position + pos > elog->log_size)
+			return 0;
+
+		if (digest_list->count) {
+			rc = tcg2_pcr_extend(dev, pcr, digest_list);
+			if (rc)
+				return rc;
+		}
+
+		log_position += pos;
+	}
+
+	elog->log_position = log_position;
+	elog->found = true;
+	return 0;
+}
+
+static int tcg2_log_parse(struct udevice *dev, struct tcg2_event_log *elog)
+{
+	struct tpml_digest_values digest_list;
+	struct tcg_efi_spec_id_event *event;
+	struct tcg_pcr_event *log;
+	u32 log_active;
+	u32 calc_size;
+	u32 active;
+	u32 count;
+	u32 evsz;
+	u32 mask;
+	u16 algo;
+	u16 len;
+	int rc;
+	u32 i;
+	u16 j;
+
+	if (elog->log_size <= offsetof(struct tcg_pcr_event, event))
+		return 0;
+
+	log = (struct tcg_pcr_event *)elog->log;
+	if (get_unaligned_le32(&log->pcr_index) != 0 ||
+	    get_unaligned_le32(&log->event_type) != EV_NO_ACTION)
+		return 0;
+
+	for (i = 0; i < sizeof(log->digest); i++) {
+		if (log->digest[i])
+			return 0;
+	}
+
+	evsz = get_unaligned_le32(&log->event_size);
+	if (evsz < offsetof(struct tcg_efi_spec_id_event, digest_sizes) ||
+	    evsz + offsetof(struct tcg_pcr_event, event) > elog->log_size)
+		return 0;
+
+	event = (struct tcg_efi_spec_id_event *)log->event;
+	if (memcmp(event->signature, TCG_EFI_SPEC_ID_EVENT_SIGNATURE_03,
+		   sizeof(TCG_EFI_SPEC_ID_EVENT_SIGNATURE_03)))
+		return 0;
+
+	if (event->spec_version_minor != TCG_EFI_SPEC_ID_EVENT_SPEC_VERSION_MINOR_TPM2 ||
+	    event->spec_version_major != TCG_EFI_SPEC_ID_EVENT_SPEC_VERSION_MAJOR_TPM2)
+		return 0;
+
+	count = get_unaligned_le32(&event->number_of_algorithms);
+	if (count > ARRAY_SIZE(tpm2_supported_algorithms))
+		return 0;
+
+	calc_size = offsetof(struct tcg_efi_spec_id_event, digest_sizes) +
+		(sizeof(struct tcg_efi_spec_id_event_algorithm_size) * count) +
+		1;
+	if (evsz != calc_size)
+		return 0;
+
+	rc = tcg2_get_active_pcr_banks(dev, &active);
+	if (rc)
+		return rc;
+
+	digest_list.count = 0;
+	log_active = 0;
+
+	for (i = 0; i < count; ++i) {
+		algo = get_unaligned_le16(&event->digest_sizes[i].algorithm_id);
+		mask = tpm2_algorithm_to_mask(algo);
+
+		if (!(active & mask))
+			return 0;
+
+		switch (algo) {
+		case TPM2_ALG_SHA1:
+		case TPM2_ALG_SHA256:
+		case TPM2_ALG_SHA384:
+		case TPM2_ALG_SHA512:
+			len = get_unaligned_le16(&event->digest_sizes[i].digest_size);
+			if (tpm2_algorithm_to_len(algo) != len)
+				return 0;
+			digest_list.digests[digest_list.count++].hash_alg = algo;
+			break;
+		default:
+			return 0;
+		}
+
+		log_active |= mask;
+	}
+
+	/* Ensure the previous firmware extended all the PCRs. */
+	if (log_active != active)
+		return 0;
+
+	/* Read PCR0 to check if previous firmware extended the PCRs or not. */
+	rc = tcg2_pcr_read(dev, 0, &digest_list);
+	if (rc)
+		return rc;
+
+	for (i = 0; i < digest_list.count; ++i) {
+		len = tpm2_algorithm_to_len(digest_list.digests[i].hash_alg);
+		for (j = 0; j < len; ++j) {
+			if (digest_list.digests[i].digest.sha512[j])
+				break;
+		}
+
+		/* PCR is non-zero; it has been extended, so skip extending. */
+		if (j != len) {
+			digest_list.count = 0;
+			break;
+		}
+	}
+
+	return tcg2_replay_eventlog(elog, dev, &digest_list,
+				    offsetof(struct tcg_pcr_event, event) +
+				    evsz);
+}
+
+int tcg2_pcr_extend(struct udevice *dev, u32 pcr_index,
+		    struct tpml_digest_values *digest_list)
+{
+	u32 rc;
+	u32 i;
+
+	for (i = 0; i < digest_list->count; i++) {
+		u32 alg = digest_list->digests[i].hash_alg;
+
+		rc = tpm2_pcr_extend(dev, pcr_index, alg,
+				     (u8 *)&digest_list->digests[i].digest,
+				     tpm2_algorithm_to_len(alg));
+		if (rc) {
+			printf("%s: error pcr:%u alg:%08x\n", __func__,
+			       pcr_index, alg);
+			return rc;
+		}
+	}
+
+	return 0;
+}
+
+int tcg2_pcr_read(struct udevice *dev, u32 pcr_index,
+		  struct tpml_digest_values *digest_list)
+{
+	struct tpm_chip_priv *priv;
+	u32 rc;
+	u32 i;
+
+	priv = dev_get_uclass_priv(dev);
+	if (!priv)
+		return -ENODEV;
+
+	for (i = 0; i < digest_list->count; i++) {
+		u32 alg = digest_list->digests[i].hash_alg;
+		u8 *digest = (u8 *)&digest_list->digests[i].digest;
+
+		rc = tpm2_pcr_read(dev, pcr_index, priv->pcr_select_min, alg,
+				   digest, tpm2_algorithm_to_len(alg), NULL);
+		if (rc) {
+			printf("%s: error pcr:%u alg:%08x\n", __func__,
+			       pcr_index, alg);
+			return rc;
+		}
+	}
+
+	return 0;
+}
+
+int tcg2_measure_data(struct udevice *dev, struct tcg2_event_log *elog,
+		      u32 pcr_index, u32 size, const u8 *data, u32 event_type,
+		      u32 event_size, const u8 *event)
+{
+	struct tpml_digest_values digest_list;
+	int rc;
+
+	if (data)
+		rc = tcg2_create_digest(dev, data, size, &digest_list);
+	else
+		rc = tcg2_create_digest(dev, event, event_size, &digest_list);
+	if (rc)
+		return rc;
+
+	rc = tcg2_pcr_extend(dev, pcr_index, &digest_list);
+	if (rc)
+		return rc;
+
+	return tcg2_log_append_check(elog, pcr_index, event_type, &digest_list,
+				     event_size, event);
+}
+
+int tcg2_log_prepare_buffer(struct udevice *dev, struct tcg2_event_log *elog,
+			    bool ignore_existing_log)
+{
+	struct tcg2_event_log log;
+	int rc;
+
+	elog->log_position = 0;
+	elog->found = false;
+
+	rc = tcg2_platform_get_log(dev, (void **)&log.log, &log.log_size);
+	if (!rc) {
+		log.log_position = 0;
+		log.found = false;
+
+		if (!ignore_existing_log) {
+			rc = tcg2_log_parse(dev, &log);
+			if (rc)
+				return rc;
+		}
+
+		if (elog->log_size) {
+			if (log.found) {
+				if (elog->log_size < log.log_position)
+					return -ENOSPC;
+
+				/*
+				 * Copy the discovered log into the user buffer
+				 * if there's enough space.
+				 */
+				memcpy(elog->log, log.log, log.log_position);
+			}
+
+			unmap_physmem(log.log, MAP_NOCACHE);
+		} else {
+			elog->log = log.log;
+			elog->log_size = log.log_size;
+		}
+
+		elog->log_position = log.log_position;
+		elog->found = log.found;
+	}
+
+	/*
+	 * Initialize the log buffer if no log was discovered and the buffer is
+	 * valid. User's can pass in their own buffer as a fallback if no
+	 * memory region is found.
+	 */
+	if (!elog->found && elog->log_size)
+		rc = tcg2_log_init(dev, elog);
+
+	return rc;
+}
+
+int tcg2_measurement_init(struct udevice **dev, struct tcg2_event_log *elog,
+			  bool ignore_existing_log)
+{
+	int rc;
+
+	rc = tcg2_platform_get_tpm2(dev);
+	if (rc)
+		return rc;
+
+	rc = tpm_auto_start(*dev);
+	if (rc)
+		return rc;
+
+	rc = tcg2_log_prepare_buffer(*dev, elog, ignore_existing_log);
+	if (rc) {
+		tcg2_measurement_term(*dev, elog, true);
+		return rc;
+	}
+
+	rc = tcg2_measure_event(*dev, elog, 0, EV_S_CRTM_VERSION,
+				strlen(version_string) + 1,
+				(u8 *)version_string);
+	if (rc) {
+		tcg2_measurement_term(*dev, elog, true);
+		return rc;
+	}
+
+	return 0;
+}
+
+void tcg2_measurement_term(struct udevice *dev, struct tcg2_event_log *elog,
+			   bool error)
+{
+	u32 event = error ? 0x1 : 0xffffffff;
+	int i;
+
+	for (i = 0; i < 8; ++i)
+		tcg2_measure_event(dev, elog, i, EV_SEPARATOR, sizeof(event),
+				   (const u8 *)&event);
+
+	if (elog->log)
+		unmap_physmem(elog->log, MAP_NOCACHE);
+}
+
+__weak int tcg2_platform_get_log(struct udevice *dev, void **addr, u32 *size)
+{
+	const __be32 *addr_prop;
+	const __be32 *size_prop;
+	int asize;
+	int ssize;
+
+	*addr = NULL;
+	*size = 0;
+
+	addr_prop = dev_read_prop(dev, "tpm_event_log_addr", &asize);
+	if (!addr_prop)
+		addr_prop = dev_read_prop(dev, "linux,sml-base", &asize);
+
+	size_prop = dev_read_prop(dev, "tpm_event_log_size", &ssize);
+	if (!size_prop)
+		size_prop = dev_read_prop(dev, "linux,sml-size", &ssize);
+
+	if (addr_prop && size_prop) {
+		u64 a = of_read_number(addr_prop, asize / sizeof(__be32));
+		u64 s = of_read_number(size_prop, ssize / sizeof(__be32));
+
+		*addr = map_physmem(a, s, MAP_NOCACHE);
+		*size = (u32)s;
+	} else {
+		struct ofnode_phandle_args args;
+		phys_addr_t a;
+		fdt_size_t s;
+
+		if (dev_read_phandle_with_args(dev, "memory-region", NULL, 0,
+					       0, &args))
+			return -ENODEV;
+
+		a = ofnode_get_addr_size(args.node, "reg", &s);
+		if (a == FDT_ADDR_T_NONE)
+			return -ENOMEM;
+
+		*addr = map_physmem(a, s, MAP_NOCACHE);
+		*size = (u32)s;
+	}
+
+	return 0;
+}
+
+__weak int tcg2_platform_get_tpm2(struct udevice **dev)
+{
+	for_each_tpm_device(*dev) {
+		if (tpm_get_version(*dev) == TPM_V2)
+			return 0;
+	}
+
+	return -ENODEV;
+}
+
+__weak void tcg2_platform_startup_error(struct udevice *dev, int rc) {}
+
 u32 tpm2_startup(struct udevice *dev, enum tpm2_startup_types mode)
 {
 	const u8 command_v2[12] = {
@@ -359,6 +1048,131 @@ u32 tpm2_get_capability(struct udevice *dev, u32 capability, u32 property,
 	return 0;
 }
 
+static int tpm2_get_num_pcr(struct udevice *dev, u32 *num_pcr)
+{
+	u8 response[(sizeof(struct tpms_capability_data) -
+		offsetof(struct tpms_capability_data, data))];
+	u32 properties_offset =
+		offsetof(struct tpml_tagged_tpm_property, tpm_property) +
+		offsetof(struct tpms_tagged_property, value);
+	u32 ret;
+
+	memset(response, 0, sizeof(response));
+	ret = tpm2_get_capability(dev, TPM2_CAP_TPM_PROPERTIES,
+				  TPM2_PT_PCR_COUNT, response, 1);
+	if (ret)
+		return ret;
+
+	*num_pcr = get_unaligned_be32(response + properties_offset);
+	if (*num_pcr > TPM2_MAX_PCRS) {
+		printf("%s: too many pcrs: %u\n", __func__, *num_pcr);
+		return -E2BIG;
+	}
+
+	return 0;
+}
+
+static bool tpm2_is_active_pcr(struct tpms_pcr_selection *selection)
+{
+	int i;
+
+	/*
+	 * check the pcr_select. If at least one of the PCRs supports the
+	 * algorithm add it on the active ones
+	 */
+	for (i = 0; i < selection->size_of_select; i++) {
+		if (selection->pcr_select[i])
+			return true;
+	}
+
+	return false;
+}
+
+int tpm2_get_pcr_info(struct udevice *dev, u32 *supported_pcr, u32 *active_pcr,
+		      u32 *pcr_banks)
+{
+	u8 response[(sizeof(struct tpms_capability_data) -
+		offsetof(struct tpms_capability_data, data))];
+	struct tpml_pcr_selection pcrs;
+	u32 num_pcr;
+	size_t i;
+	u32 ret;
+
+	*supported_pcr = 0;
+	*active_pcr = 0;
+	*pcr_banks = 0;
+	memset(response, 0, sizeof(response));
+	ret = tpm2_get_capability(dev, TPM2_CAP_PCRS, 0, response, 1);
+	if (ret)
+		return ret;
+
+	pcrs.count = get_unaligned_be32(response);
+	/*
+	 * We only support 5 algorithms for now so check against that
+	 * instead of TPM2_NUM_PCR_BANKS
+	 */
+	if (pcrs.count > ARRAY_SIZE(tpm2_supported_algorithms) ||
+	    pcrs.count < 1) {
+		printf("%s: too many pcrs: %u\n", __func__, pcrs.count);
+		return -EMSGSIZE;
+	}
+
+	ret = tpm2_get_num_pcr(dev, &num_pcr);
+	if (ret)
+		return ret;
+
+	for (i = 0; i < pcrs.count; i++) {
+		/*
+		 * Definition of TPMS_PCR_SELECTION Structure
+		 * hash: u16
+		 * size_of_select: u8
+		 * pcr_select: u8 array
+		 *
+		 * The offsets depend on the number of the device PCRs
+		 * so we have to calculate them based on that
+		 */
+		u32 hash_offset = offsetof(struct tpml_pcr_selection, selection) +
+			i * offsetof(struct tpms_pcr_selection, pcr_select) +
+			i * ((num_pcr + 7) / 8);
+		u32 size_select_offset =
+			hash_offset + offsetof(struct tpms_pcr_selection,
+					       size_of_select);
+		u32 pcr_select_offset =
+			hash_offset + offsetof(struct tpms_pcr_selection,
+					       pcr_select);
+
+		pcrs.selection[i].hash =
+			get_unaligned_be16(response + hash_offset);
+		pcrs.selection[i].size_of_select =
+			__get_unaligned_be(response + size_select_offset);
+		if (pcrs.selection[i].size_of_select > TPM2_PCR_SELECT_MAX) {
+			printf("%s: pcrs selection too large: %u\n", __func__,
+			       pcrs.selection[i].size_of_select);
+			return -ENOBUFS;
+		}
+		/* copy the array of pcr_select */
+		memcpy(pcrs.selection[i].pcr_select, response + pcr_select_offset,
+		       pcrs.selection[i].size_of_select);
+	}
+
+	for (i = 0; i < pcrs.count; i++) {
+		u32 hash_mask = tpm2_algorithm_to_mask(pcrs.selection[i].hash);
+
+		if (hash_mask) {
+			*supported_pcr |= hash_mask;
+			if (tpm2_is_active_pcr(&pcrs.selection[i]))
+				*active_pcr |= hash_mask;
+		} else {
+			printf("%s: unknown algorithm %x\n", __func__,
+			       pcrs.selection[i].hash);
+		}
+	}
+
+	*pcr_banks = pcrs.count;
+
+	return 0;
+}
+
 u32 tpm2_dam_reset(struct udevice *dev, const char *pw, const ssize_t pw_sz)
 {
 	u8 command_v2[COMMAND_BUFFER_SIZE] = {