[PATCH v11 3/8] tpm: Support boot measurements

Ilias Apalodimas ilias.apalodimas at linaro.org
Wed Aug 9 10:34:58 CEST 2023


Hi Eddie


On Mon, Aug 07, 2023 at 02:25:37PM -0500, Eddie James wrote:
> 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 at linux.ibm.com>
> ---
> Changes since v10:
>  - Fix compile warning for armv7 (thanks Ilias)
> 

This doesn't apply cleanly and I think it's because of commit
d12c3efe53107.  This was merged after my rebase.  Can you rebase on top of
-master and resend?

Thanks
/Ilias
> Changes since v8:
>  - Fix log parsing again - any data corruption seen while replaying the
>    event log was failing the entire measurement.
>  - Added an option to ignore the existing log. This should only be used
>    for systems that know that U-Boot is the first stage bootloader. This
>    is necessary because the reserved memory region may persist through
>    resets and so U-Boot attempts to append to the previous boot's log.
> 
> Changes since v7:
>  - Change name of tcg2_init_log and add more documentation
>  - Add a check, when parsing the event log header, to ensure that the
>    previous stage bootloader used all the active PCRs.
>  - Change name of tcg2_log_find_end
>  - Fix the greater than or equal to check to exit the log parsing
>  - Make sure log_position is 0 if there is any error discovering the log
>  - Return errors parsing the log if the data is corrupt so that we don't
>    end up with half a log
> 
> Changes since v6:
>  - Added Linaro copyright for all the EFI moved code
>  - Changed tcg2_init_log (and by extension, tcg2_measurement_init) to
>    copy any discovered event log to the user's log if passed in.
> 
> Changes since v5:
>  - Remove unused platform_get_eventlog in efi_tcg2.c
>  - First look for tpm_event_log_* properties instead of linux,sml-*
>  - Fix efi_tcg2.c compilation
>  - Select SHA* configs
> 
> Changes since v4:
>  - Remove tcg2_measure_event function and check for NULL data in
>    tcg2_measure_data
>  - Use tpm_auto_startup
>  - Fix efi_tcg2.c compilation for removing tcg2_pcr_read function
> 
> Changes since v3:
>  - Reordered headers
>  - Refactored more of EFI code into common code
>     Removed digest_info structure and instead used the common alg_to_mask
>       and alg_to_len
>     Improved event log parsing in common code to get it equivalent to EFI
>       Common code now extends PCR if previous bootloader stage couldn't
>       No need to allocate memory in the common code, so EFI copies the
>       discovered buffer like it did before
>     Rename efi measure_event function
> 
> Changes since v1:
>  - Refactor TPM layer functions to allow EFI system to use them, and
>    remove duplicate EFI functions
> 
>  include/efi_tcg2.h        |   44 --
>  include/tpm-v2.h          |  259 +++++++++
>  lib/Kconfig               |    4 +
>  lib/efi_loader/efi_tcg2.c | 1054 +++----------------------------------
>  lib/tpm-v2.c              |  814 ++++++++++++++++++++++++++++
>  5 files changed, 1154 insertions(+), 1021 deletions(-)
> 
> diff --git a/include/efi_tcg2.h b/include/efi_tcg2.h
> index b1c3abd097..b21c5cb3dd 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 6684033deb..33dd103767 100644
> --- a/include/tpm-v2.h
> +++ b/include/tpm-v2.h
> @@ -216,6 +216,50 @@ struct tcg_pcr_event2 {
>  	u8 event[];
>  } __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.
>   *
> @@ -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,
> @@ -421,6 +485,188 @@ enum {
>  	HR_NV_INDEX		= TPM_HT_NV_INDEX << HR_SHIFT,
>  };
>  
> +/**
> + * 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.
>   *
> @@ -540,6 +786,19 @@ u32 tpm2_pcr_read(struct udevice *dev, u32 idx, unsigned int idx_min_sz,
>  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.
>   *
> diff --git a/lib/Kconfig b/lib/Kconfig
> index c8b3ec1ec9..cd37cba511 100644
> --- a/lib/Kconfig
> +++ b/lib/Kconfig
> @@ -423,6 +423,10 @@ 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 a83ae7a46c..5f0f4b5dd2 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++;
> @@ -350,66 +142,6 @@ static efi_status_t tcg2_agile_log_append(u32 pcr_index, u32 event_type,
>  	return ret;
>  }
>  
> -/**
> - * 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
>   *
> @@ -485,239 +217,6 @@ static int tpm2_get_manufacturer_id(struct udevice *dev, u32 *manufacturer_id)
>  	return 0;
>  }
>  
> -/**
> - * 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:
> -			EFI_PRINT("Unsupported algorithm %x\n", hash_alg);
> -			return EFI_INVALID_PARAMETER;
> -		}
> -		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
>   *
> @@ -759,7 +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;
> @@ -855,7 +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;
> @@ -890,6 +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;
> @@ -905,16 +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:
> @@ -935,7 +439,7 @@ 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++;
>  	}
>  
> @@ -975,7 +479,7 @@ 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;
>  
> @@ -1084,7 +588,7 @@ 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;
>  
> @@ -1119,7 +623,7 @@ 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);
>  	}
>  
> @@ -1182,7 +686,7 @@ 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;
>  
> @@ -1211,6 +715,7 @@ 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) {
> @@ -1218,8 +723,12 @@ 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);
> @@ -1270,397 +779,6 @@ static const struct efi_tcg2_protocol efi_tcg2_protocol = {
>  	.get_result_of_set_active_pcr_banks = efi_tcg2_get_result_of_set_active_pcr_banks,
>  };
>  
> -/**
> - * 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
>   */
> @@ -1722,7 +840,7 @@ 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
> @@ -1732,14 +850,13 @@ 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;
>  
> @@ -1766,9 +883,8 @@ 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;
>  }
> @@ -1784,12 +900,11 @@ 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;
>  
> @@ -1808,7 +923,6 @@ 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;
> @@ -1819,34 +933,20 @@ 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)
> @@ -1899,8 +999,8 @@ 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;
>  }
> @@ -2011,8 +1111,8 @@ 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;
>  
> @@ -2163,7 +1263,7 @@ 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);
> @@ -2217,7 +1317,7 @@ 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;
>  
> @@ -2242,7 +1342,7 @@ 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;
> @@ -2267,7 +1367,7 @@ 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;
>  
> @@ -2275,9 +1375,9 @@ 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;
>  
> @@ -2293,8 +1393,8 @@ 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;
>  	}
> @@ -2317,13 +1417,13 @@ 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;
>  }
>  
> @@ -2348,19 +1448,19 @@ 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);
> @@ -2380,19 +1480,19 @@ 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;
> @@ -2462,7 +1562,7 @@ 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;
>  
> @@ -2488,7 +1588,7 @@ 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 9ab5b46df1..bd0fb078dc 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 at 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] = {
> -- 
> 2.39.3
> 


More information about the U-Boot mailing list