Merge tag 'efi-2021-01-rc3' of https://gitlab.denx.de/u-boot/custodians/u-boot-efiWIP/14Nov2020

Pull request for UEFI sub-system for efi-2021-01-rc3

A part of the EFI_TCG2_PROTOCOL is implemented.
A unit test is supplied.

The following bugs are fixed:

* incorrect buffer size in efi_file_setinfo() leading to creash in SCT
* a crash in UEFI selftest on the sandbox due to removed drivers
* missing newlines in log message for the UEFI RNG driver

13 files changed, 816 insertions, 7 deletions

diff --git a/include/efi_loader.h b/include/efi_loader.h
index f550ced568..3c68b85b68 100644
--- a/include/efi_loader.h
+++ b/include/efi_loader.h
@@ -59,6 +59,9 @@ extern efi_handle_t efi_root;
 /* Set to EFI_SUCCESS when initialized */
 extern efi_status_t efi_obj_list_initialized;
 
+/* Flag used by the selftest to avoid detaching devices in ExitBootServices() */
+extern bool efi_st_keep_devices;
+
 /* EFI system partition */
 extern struct efi_system_partition {
 	enum if_type if_type;
@@ -405,6 +408,8 @@ efi_status_t efi_console_register(void);
 efi_status_t efi_disk_register(void);
 /* Called by efi_init_obj_list() to install EFI_RNG_PROTOCOL */
 efi_status_t efi_rng_register(void);
+/* Called by efi_init_obj_list() to install EFI_TCG2_PROTOCOL */
+efi_status_t efi_tcg2_register(void);
 /* Create handles and protocols for the partitions of a block device */
 int efi_disk_create_partitions(efi_handle_t parent, struct blk_desc *desc,
 			       const char *if_typename, int diskid,
diff --git a/include/efi_tcg2.h b/include/efi_tcg2.h
new file mode 100644
index 0000000000..4214f767ea
--- /dev/null
+++ b/include/efi_tcg2.h
@@ -0,0 +1,94 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Defines data structures and APIs that allow an OS to interact with UEFI
+ * firmware to query information about the device
+ *
+ * Copyright (c) 2020, Linaro Limited
+ */
+
+#if !defined _EFI_TCG2_PROTOCOL_H_
+#define _EFI_TCG2_PROTOCOL_H_
+
+#include <tpm-v2.h>
+
+#define EFI_TCG2_PROTOCOL_GUID \
+	EFI_GUID(0x607f766c, 0x7455, 0x42be, 0x93, \
+		 0x0b, 0xe4, 0xd7, 0x6d, 0xb2, 0x72, 0x0f)
+
+/* TPMV2 only */
+#define TCG2_EVENT_LOG_FORMAT_TCG_2 0x00000002
+
+/* SHA1, SHA256, SHA384, SHA512, TPM_ALG_SM3_256 */
+#define MAX_HASH_COUNT 5
+/* Algorithm Registry */
+#define EFI_TCG2_BOOT_HASH_ALG_SHA1    0x00000001
+#define EFI_TCG2_BOOT_HASH_ALG_SHA256  0x00000002
+#define EFI_TCG2_BOOT_HASH_ALG_SHA384  0x00000004
+#define EFI_TCG2_BOOT_HASH_ALG_SHA512  0x00000008
+#define EFI_TCG2_BOOT_HASH_ALG_SM3_256 0x00000010
+
+typedef u32 efi_tcg_event_log_bitmap;
+typedef u32 efi_tcg_event_log_format;
+typedef u32 efi_tcg_event_algorithm_bitmap;
+
+struct efi_tcg2_version {
+	u8 major;
+	u8 minor;
+};
+
+struct efi_tcg2_event_header {
+	u32 header_size;
+	u16 header_version;
+	u32 pcr_index;
+	u32 event_type;
+} __packed;
+
+struct efi_tcg2_event {
+	u32 size;
+	struct efi_tcg2_event_header header;
+	u8 event[];
+} __packed;
+
+struct efi_tcg2_boot_service_capability {
+	u8 size;
+	struct efi_tcg2_version structure_version;
+	struct efi_tcg2_version protocol_version;
+	efi_tcg_event_algorithm_bitmap hash_algorithm_bitmap;
+	efi_tcg_event_log_bitmap supported_event_logs;
+	u8 tpm_present_flag;
+	u16 max_command_size;
+	u16 max_response_size;
+	u32 manufacturer_id;
+	u32 number_of_pcr_banks;
+	efi_tcg_event_algorithm_bitmap active_pcr_banks;
+};
+
+#define boot_service_capability_min \
+	sizeof(struct efi_tcg2_boot_service_capability) - \
+	offsetof(struct efi_tcg2_boot_service_capability, number_of_pcr_banks)
+
+struct efi_tcg2_protocol {
+	efi_status_t (EFIAPI * get_capability)(struct efi_tcg2_protocol *this,
+					       struct efi_tcg2_boot_service_capability *capability);
+	efi_status_t (EFIAPI * get_eventlog)(struct efi_tcg2_protocol *this,
+					     efi_tcg_event_log_format log_format,
+					     u64 *event_log_location, u64 *event_log_last_entry,
+					     bool *event_log_truncated);
+	efi_status_t (EFIAPI * hash_log_extend_event)(struct efi_tcg2_protocol *this,
+						      u64 flags, u64 data_to_hash,
+						      u64 data_to_hash_len,
+						      struct efi_tcg2_event *efi_tcg_event);
+	efi_status_t (EFIAPI * submit_command)(struct efi_tcg2_protocol *this,
+					       u32 input_parameter_block_size,
+					       u8 *input_parameter_block,
+					       u32 output_parameter_block_size,
+					       u8 *output_parameter_block);
+	efi_status_t (EFIAPI * get_active_pcr_banks)(struct efi_tcg2_protocol *this,
+						     u32 *active_pcr_banks);
+	efi_status_t (EFIAPI * set_active_pcr_banks)(struct efi_tcg2_protocol *this,
+						     u32 active_pcr_banks);
+	efi_status_t (EFIAPI * get_result_of_set_active_pcr_banks)(struct efi_tcg2_protocol *this,
+								   u32 *operation_present,
+								   u32 *response);
+};
+#endif
diff --git a/include/tpm-v2.h b/include/tpm-v2.h
index f6c045d354..74c14fe7c5 100644
--- a/include/tpm-v2.h
+++ b/include/tpm-v2.h
@@ -1,6 +1,13 @@
 /* SPDX-License-Identifier: GPL-2.0+ */
 /*
+ * Defines APIs and structures that allow software to interact with a
+ * TPM2 device
+ *
+ * Copyright (c) 2020 Linaro
  * Copyright (c) 2018 Bootlin
+ *
+ * https://trustedcomputinggroup.org/resource/tss-overview-common-structures-specification/
+ *
  * Author: Miquel Raynal <miquel.raynal@bootlin.com>
  */
 
@@ -11,6 +18,74 @@
 
 #define TPM2_DIGEST_LEN		32
 
+#define TPM2_MAX_PCRS 32
+#define TPM2_PCR_SELECT_MAX ((TPM2_MAX_PCRS + 7) / 8)
+#define TPM2_MAX_CAP_BUFFER 1024
+#define TPM2_MAX_TPM_PROPERTIES ((TPM2_MAX_CAP_BUFFER - sizeof(u32) /* TPM2_CAP */ - \
+				 sizeof(u32)) / sizeof(struct tpms_tagged_property))
+
+/*
+ *  We deviate from this draft of the specification by increasing the value of
+ *  TPM2_NUM_PCR_BANKS from 3 to 16 to ensure compatibility with TPM2
+ *  implementations that have enabled a larger than typical number of PCR
+ *  banks. This larger value for TPM2_NUM_PCR_BANKS is expected to be included
+ *  in a future revision of the specification.
+ */
+#define TPM2_NUM_PCR_BANKS 16
+
+/* Definition of (UINT32) TPM2_CAP Constants */
+#define TPM2_CAP_PCRS 0x00000005U
+#define TPM2_CAP_TPM_PROPERTIES 0x00000006U
+
+/* Definition of (UINT32) TPM2_PT Constants */
+#define TPM2_PT_GROUP			(u32)(0x00000100)
+#define TPM2_PT_FIXED			(u32)(TPM2_PT_GROUP * 1)
+#define TPM2_PT_MANUFACTURER		(u32)(TPM2_PT_FIXED + 5)
+#define TPM2_PT_PCR_COUNT		(u32)(TPM2_PT_FIXED + 18)
+#define TPM2_PT_MAX_COMMAND_SIZE	(u32)(TPM2_PT_FIXED + 30)
+#define TPM2_PT_MAX_RESPONSE_SIZE	(u32)(TPM2_PT_FIXED + 31)
+
+/* TPMS_TAGGED_PROPERTY Structure */
+struct tpms_tagged_property {
+	u32 property;
+	u32 value;
+} __packed;
+
+/* TPMS_PCR_SELECTION Structure */
+struct tpms_pcr_selection {
+	u16 hash;
+	u8 size_of_select;
+	u8 pcr_select[TPM2_PCR_SELECT_MAX];
+} __packed;
+
+/* TPML_PCR_SELECTION Structure */
+struct tpml_pcr_selection {
+	u32 count;
+	struct tpms_pcr_selection selection[TPM2_NUM_PCR_BANKS];
+} __packed;
+
+/* TPML_TAGGED_TPM_PROPERTY Structure */
+struct tpml_tagged_tpm_property {
+	u32 count;
+	struct tpms_tagged_property tpm_property[TPM2_MAX_TPM_PROPERTIES];
+} __packed;
+
+/* TPMU_CAPABILITIES Union */
+union tpmu_capabilities {
+	/*
+	 * Non exhaustive. Only added the structs needed for our
+	 * current code
+	 */
+	struct tpml_pcr_selection assigned_pcr;
+	struct tpml_tagged_tpm_property tpm_properties;
+} __packed;
+
+/* TPMS_CAPABILITY_DATA Structure */
+struct tpms_capability_data {
+	u32 capability;
+	union tpmu_capabilities data;
+} __packed;
+
 /**
  * TPM2 Structure Tags for command/response buffers.
  *
@@ -123,11 +198,13 @@ enum tpm2_return_codes {
  * TPM2 algorithms.
  */
 enum tpm2_algorithms {
+	TPM2_ALG_SHA1		= 0x04,
 	TPM2_ALG_XOR		= 0x0A,
 	TPM2_ALG_SHA256		= 0x0B,
 	TPM2_ALG_SHA384		= 0x0C,
 	TPM2_ALG_SHA512		= 0x0D,
 	TPM2_ALG_NULL		= 0x10,
+	TPM2_ALG_SM3_256	= 0x12,
 };
 
 /* NV index attributes */
diff --git a/lib/efi_loader/Kconfig b/lib/efi_loader/Kconfig
index 075481428c..29ea14b2ee 100644
--- a/lib/efi_loader/Kconfig
+++ b/lib/efi_loader/Kconfig
@@ -184,6 +184,13 @@ config EFI_RNG_PROTOCOL
 	  Provide a EFI_RNG_PROTOCOL implementation using the hardware random
 	  number generator of the platform.
 
+config EFI_TCG2_PROTOCOL
+	bool "EFI_TCG2_PROTOCOL support"
+	depends on TPM_V2
+	help
+	  Provide a EFI_TCG2_PROTOCOL implementation using the TPM hardware
+	  of the platform.
+
 config EFI_LOAD_FILE2_INITRD
 	bool "EFI_FILE_LOAD2_PROTOCOL for Linux initial ramdisk"
 	default n
diff --git a/lib/efi_loader/Makefile b/lib/efi_loader/Makefile
index 8892fb01e1..cd4b252a41 100644
--- a/lib/efi_loader/Makefile
+++ b/lib/efi_loader/Makefile
@@ -53,6 +53,7 @@ obj-$(CONFIG_NET) += efi_net.o
 obj-$(CONFIG_GENERATE_ACPI_TABLE) += efi_acpi.o
 obj-$(CONFIG_GENERATE_SMBIOS_TABLE) += efi_smbios.o
 obj-$(CONFIG_EFI_RNG_PROTOCOL) += efi_rng.o
+obj-$(CONFIG_EFI_TCG2_PROTOCOL) += efi_tcg2.o
 obj-$(CONFIG_EFI_LOAD_FILE2_INITRD) += efi_load_initrd.o
 obj-y += efi_signature.o
 
diff --git a/lib/efi_loader/efi_boottime.c b/lib/efi_loader/efi_boottime.c
index dfa71b1774..246b59d3b3 100644
--- a/lib/efi_loader/efi_boottime.c
+++ b/lib/efi_loader/efi_boottime.c
@@ -38,6 +38,9 @@ LIST_HEAD(efi_event_queue);
 /* Flag to disable timer activity in ExitBootServices() */
 static bool timers_enabled = true;
 
+/* Flag used by the selftest to avoid detaching devices in ExitBootServices() */
+bool efi_st_keep_devices;
+
 /* List of all events registered by RegisterProtocolNotify() */
 LIST_HEAD(efi_register_notify_events);
 
@@ -1996,10 +1999,12 @@ static efi_status_t EFIAPI efi_exit_boot_services(efi_handle_t image_handle,
 			list_del(&evt->link);
 	}
 
-	if IS_ENABLED(CONFIG_USB_DEVICE)
-		udc_disconnect();
-	board_quiesce_devices();
-	dm_remove_devices_flags(DM_REMOVE_ACTIVE_ALL);
+	if (!efi_st_keep_devices) {
+		if IS_ENABLED(CONFIG_USB_DEVICE)
+			udc_disconnect();
+		board_quiesce_devices();
+		dm_remove_devices_flags(DM_REMOVE_ACTIVE_ALL);
+	}
 
 	/* Patch out unsupported runtime function */
 	efi_runtime_detach();
diff --git a/lib/efi_loader/efi_file.c b/lib/efi_loader/efi_file.c
index 44fafae058..72b7ec1e63 100644
--- a/lib/efi_loader/efi_file.c
+++ b/lib/efi_loader/efi_file.c
@@ -723,7 +723,7 @@ static efi_status_t EFIAPI efi_file_setinfo(struct efi_file_handle *file,
 			goto out;
 		}
 		/* Check for renaming */
-		new_file_name = malloc(utf16_utf8_strlen(info->file_name));
+		new_file_name = malloc(utf16_utf8_strlen(info->file_name) + 1);
 		if (!new_file_name) {
 			ret = EFI_OUT_OF_RESOURCES;
 			goto out;
diff --git a/lib/efi_loader/efi_rng.c b/lib/efi_loader/efi_rng.c
index a8a87007b6..8bdadad0a9 100644
--- a/lib/efi_loader/efi_rng.c
+++ b/lib/efi_loader/efi_rng.c
@@ -166,13 +166,13 @@ efi_status_t efi_rng_register(void)
 
 	ret = platform_get_rng_device(&dev);
 	if (ret != EFI_SUCCESS) {
-		log_warning("Missing RNG device for EFI_RNG_PROTOCOL");
+		log_warning("Missing RNG device for EFI_RNG_PROTOCOL\n");
 		return EFI_SUCCESS;
 	}
 	ret = efi_add_protocol(efi_root, &efi_guid_rng_protocol,
 			       (void *)&efi_rng_protocol);
 	if (ret != EFI_SUCCESS)
-		log_err("Cannot install EFI_RNG_PROTOCOL");
+		log_err("Cannot install EFI_RNG_PROTOCOL\n");
 
 	return ret;
 }
diff --git a/lib/efi_loader/efi_setup.c b/lib/efi_loader/efi_setup.c
index 45226c5c1a..e206b60bb8 100644
--- a/lib/efi_loader/efi_setup.c
+++ b/lib/efi_loader/efi_setup.c
@@ -156,6 +156,13 @@ efi_status_t efi_init_obj_list(void)
 		if (ret != EFI_SUCCESS)
 			goto out;
 	}
+
+	if (IS_ENABLED(CONFIG_EFI_TCG2_PROTOCOL)) {
+		ret = efi_tcg2_register();
+		if (ret != EFI_SUCCESS)
+			goto out;
+	}
+
 	/* Initialize variable services */
 	ret = efi_init_variables();
 	if (ret != EFI_SUCCESS)
diff --git a/lib/efi_loader/efi_tcg2.c b/lib/efi_loader/efi_tcg2.c
new file mode 100644
index 0000000000..f5812ed2e9
--- /dev/null
+++ b/lib/efi_loader/efi_tcg2.c
@@ -0,0 +1,534 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Defines APIs that allow an OS to interact with UEFI firmware to query
+ * information about the device.
+ * https://trustedcomputinggroup.org/resource/tcg-efi-protocol-specification/
+ *
+ * Copyright (c) 2020, Linaro Limited
+ */
+
+#define LOG_CATEGORY LOGC_EFI
+#include <common.h>
+#include <dm.h>
+#include <efi_loader.h>
+#include <efi_tcg2.h>
+#include <log.h>
+#include <tpm-v2.h>
+#include <linux/unaligned/access_ok.h>
+#include <linux/unaligned/generic.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/*
+ * When requesting TPM2_CAP_TPM_PROPERTIES the value is on a standard offset.
+ * Since the current tpm2_get_capability() response buffers starts at
+ * 'union tpmu_capabilities data' of 'struct tpms_capability_data', calculate
+ * the response size and offset once for all consumers
+ */
+#define TPM2_RESPONSE_BUFFER_SIZE (sizeof(struct tpms_capability_data) - \
+				   offsetof(struct tpms_capability_data, data))
+#define properties_offset (offsetof(struct tpml_tagged_tpm_property, tpm_property) + \
+			   offsetof(struct tpms_tagged_property, value))
+
+const efi_guid_t efi_guid_tcg2_protocol = EFI_TCG2_PROTOCOL_GUID;
+
+/**
+ * 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)) {
+		if (tpm_get_version(*dev) == TPM_V2)
+			return EFI_SUCCESS;
+	}
+	return EFI_NOT_FOUND;
+}
+
+/**
+ * tpm2_get_max_command_size() - get the supported max command size
+ *
+ * @dev:		TPM device
+ * @max_command_size:	output buffer for the size
+ *
+ * Return: 0 on success, -1 on error
+ */
+static int tpm2_get_max_command_size(struct udevice *dev, u16 *max_command_size)
+{
+	u8 response[TPM2_RESPONSE_BUFFER_SIZE];
+	u32 ret;
+
+	memset(response, 0, sizeof(response));
+	ret = tpm2_get_capability(dev, TPM2_CAP_TPM_PROPERTIES,
+				  TPM2_PT_MAX_COMMAND_SIZE, response, 1);
+	if (ret)
+		return -1;
+
+	*max_command_size = (uint16_t)get_unaligned_be32(response +
+							 properties_offset);
+
+	return 0;
+}
+
+/**
+ * tpm2_get_max_response_size() - get the supported max response size
+ *
+ * @dev:		TPM device
+ * @max_response_size:	output buffer for the size
+ *
+ * Return: 0 on success, -1 on error
+ */
+static int tpm2_get_max_response_size(struct udevice *dev,
+				      u16 *max_response_size)
+{
+	u8 response[TPM2_RESPONSE_BUFFER_SIZE];
+	u32 ret;
+
+	memset(response, 0, sizeof(response));
+	ret = tpm2_get_capability(dev, TPM2_CAP_TPM_PROPERTIES,
+				  TPM2_PT_MAX_RESPONSE_SIZE, response, 1);
+	if (ret)
+		return -1;
+
+	*max_response_size = (uint16_t)get_unaligned_be32(response +
+							  properties_offset);
+
+	return 0;
+}
+
+/**
+ * tpm2_get_manufacturer_id() - get the manufacturer ID
+ *
+ * @dev:		TPM device
+ * @manufacturer_id:	output buffer for the id
+ *
+ * Return: 0 on success, -1 on error
+ */
+static int tpm2_get_manufacturer_id(struct udevice *dev, u32 *manufacturer_id)
+{
+	u8 response[TPM2_RESPONSE_BUFFER_SIZE];
+	u32 ret;
+
+	memset(response, 0, sizeof(response));
+	ret = tpm2_get_capability(dev, TPM2_CAP_TPM_PROPERTIES,
+				  TPM2_PT_MANUFACTURER, response, 1);
+	if (ret)
+		return -1;
+
+	*manufacturer_id = get_unaligned_be32(response + properties_offset);
+
+	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
+ */
+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;
+	int i, tpm_ret;
+
+	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++) {
+		switch (pcrs.selection[i].hash) {
+		case TPM2_ALG_SHA1:
+			 *supported_pcr |= EFI_TCG2_BOOT_HASH_ALG_SHA1;
+			if (is_active_pcr(&pcrs.selection[i]))
+				*active_pcr |= EFI_TCG2_BOOT_HASH_ALG_SHA1;
+			break;
+		case TPM2_ALG_SHA256:
+			*supported_pcr |= EFI_TCG2_BOOT_HASH_ALG_SHA256;
+			if (is_active_pcr(&pcrs.selection[i]))
+				*active_pcr |= EFI_TCG2_BOOT_HASH_ALG_SHA256;
+			break;
+		case TPM2_ALG_SHA384:
+			*supported_pcr |= EFI_TCG2_BOOT_HASH_ALG_SHA384;
+			if (is_active_pcr(&pcrs.selection[i]))
+				*active_pcr |= EFI_TCG2_BOOT_HASH_ALG_SHA384;
+			break;
+		case TPM2_ALG_SHA512:
+			*supported_pcr |= EFI_TCG2_BOOT_HASH_ALG_SHA512;
+			if (is_active_pcr(&pcrs.selection[i]))
+				*active_pcr |= EFI_TCG2_BOOT_HASH_ALG_SHA512;
+			break;
+		case TPM2_ALG_SM3_256:
+			*supported_pcr |= EFI_TCG2_BOOT_HASH_ALG_SM3_256;
+			if (is_active_pcr(&pcrs.selection[i]))
+				*active_pcr |= EFI_TCG2_BOOT_HASH_ALG_SM3_256;
+			break;
+		default:
+			EFI_PRINT("Unknown algorithm %x\n",
+				  pcrs.selection[i].hash);
+			break;
+		}
+	}
+
+	*pcr_banks = pcrs.count;
+
+	return 0;
+out:
+	return -1;
+}
+
+/**
+ * get_capability() - protocol capability information and state information
+ *
+ * @this:		TCG2 protocol instance
+ * @capability:		caller allocated memory with size field to the size of
+ *			the structure allocated
+
+ * Return:	status code
+ */
+static efi_status_t EFIAPI
+get_capability(struct efi_tcg2_protocol *this,
+	       struct efi_tcg2_boot_service_capability *capability)
+{
+	struct udevice *dev;
+	efi_status_t efi_ret;
+	int ret;
+
+	EFI_ENTRY("%p, %p", this, capability);
+
+	if (!this || !capability) {
+		efi_ret = EFI_INVALID_PARAMETER;
+		goto out;
+	}
+
+	if (capability->size < boot_service_capability_min) {
+		capability->size = boot_service_capability_min;
+		efi_ret = EFI_BUFFER_TOO_SMALL;
+		goto out;
+	}
+
+	if (capability->size < sizeof(*capability)) {
+		capability->size = sizeof(*capability);
+		efi_ret = EFI_BUFFER_TOO_SMALL;
+		goto out;
+	}
+
+	capability->structure_version.major = 1;
+	capability->structure_version.minor = 1;
+	capability->protocol_version.major = 1;
+	capability->protocol_version.minor = 1;
+
+	efi_ret = platform_get_tpm2_device(&dev);
+	if (efi_ret != EFI_SUCCESS) {
+		capability->supported_event_logs = 0;
+		capability->hash_algorithm_bitmap = 0;
+		capability->tpm_present_flag = false;
+		capability->max_command_size = 0;
+		capability->max_response_size = 0;
+		capability->manufacturer_id = 0;
+		capability->number_of_pcr_banks = 0;
+		capability->active_pcr_banks = 0;
+
+		efi_ret = EFI_SUCCESS;
+		goto out;
+	}
+
+	/* We only allow a TPMv2 device to register the EFI protocol */
+	capability->supported_event_logs = TCG2_EVENT_LOG_FORMAT_TCG_2;
+
+	capability->tpm_present_flag = true;
+
+	/* Supported and active PCRs */
+	capability->hash_algorithm_bitmap = 0;
+	capability->active_pcr_banks = 0;
+	ret = tpm2_get_pcr_info(dev, &capability->hash_algorithm_bitmap,
+				&capability->active_pcr_banks,
+				&capability->number_of_pcr_banks);
+	if (ret) {
+		efi_ret = EFI_DEVICE_ERROR;
+		goto out;
+	}
+
+	/* Max command size */
+	ret = tpm2_get_max_command_size(dev, &capability->max_command_size);
+	if (ret) {
+		efi_ret = EFI_DEVICE_ERROR;
+		goto out;
+	}
+
+	/* Max response size */
+	ret = tpm2_get_max_response_size(dev, &capability->max_response_size);
+	if (ret) {
+		efi_ret = EFI_DEVICE_ERROR;
+		goto out;
+	}
+
+	/* Manufacturer ID */
+	ret = tpm2_get_manufacturer_id(dev, &capability->manufacturer_id);
+	if (ret) {
+		efi_ret = EFI_DEVICE_ERROR;
+		goto out;
+	}
+
+	return EFI_EXIT(EFI_SUCCESS);
+out:
+	return EFI_EXIT(efi_ret);
+}
+
+/**
+ * get_eventlog() - retrieve the the address of an event log and its last entry
+ *
+ * @this:			TCG2 protocol instance
+ * @log_format:			type of event log format
+ * @event_log_location:		pointer to the memory address of the event log
+ * @event_log_last_entry:	pointer to the address of the start of the last
+ *				entry in the event log in memory, if log contains
+ *				more than 1 entry
+ * @event_log_truncated:	set to true, if the Event Log is missing at i
+ *				least one entry
+ *
+ * Return:	status code
+ */
+static efi_status_t EFIAPI
+get_eventlog(struct efi_tcg2_protocol *this,
+	     efi_tcg_event_log_format log_format, u64 *event_log_location,
+	     u64 *event_log_last_entry, bool *event_log_truncated)
+{
+	return EFI_UNSUPPORTED;
+}
+
+/**
+ * hash_log_extend_event()- extend and optionally log events
+ *
+ * @this:			TCG2 protocol instance
+ * @flags:			bitmap providing additional information on the
+ *				operation
+ * @data_to_hash:		physical address of the start of the data buffer
+ *				to be hashed
+ * @data_to_hash_len:		the length in bytes of the buffer referenced by
+ *				data_to_hash
+ * @efi_tcg_event:		pointer to data buffer containing information
+ *				about the event
+ *
+ * Return:	status code
+ */
+static efi_status_t EFIAPI
+hash_log_extend_event(struct efi_tcg2_protocol *this, u64 flags,
+		      u64 data_to_hash, u64 data_to_hash_len,
+		      struct efi_tcg2_event *efi_tcg_event)
+{
+	return EFI_UNSUPPORTED;
+}
+
+/**
+ * submit_command() - Send command to the TPM
+ *
+ * @this:			TCG2 protocol instance
+ * @input_param_block_size:	size of the TPM input parameter block
+ * @input_param_block:		pointer to the TPM input parameter block
+ * @output_param_block_size:	size of the TPM output parameter block
+ * @output_param_block:		pointer to the TPM output parameter block
+ *
+ * Return:	status code
+ */
+efi_status_t EFIAPI
+submit_command(struct efi_tcg2_protocol *this, u32 input_param_block_size,
+	       u8 *input_param_block, u32 output_param_block_size,
+	       u8 *output_param_block)
+{
+	return EFI_UNSUPPORTED;
+}
+
+/**
+ * get_active_pcr_banks() - returns the currently active PCR banks
+ *
+ * @this:			TCG2 protocol instance
+ * @active_pcr_banks:		pointer for receiving the bitmap of currently
+ *				active PCR banks
+ *
+ * Return:	status code
+ */
+efi_status_t EFIAPI
+get_active_pcr_banks(struct efi_tcg2_protocol *this, u32 *active_pcr_banks)
+{
+	return EFI_UNSUPPORTED;
+}
+
+/**
+ * set_active_pcr_banks() - sets the currently active PCR banks
+ *
+ * @this:			TCG2 protocol instance
+ * @active_pcr_banks:		bitmap of the requested active PCR banks
+ *
+ * Return:	status code
+ */
+efi_status_t EFIAPI
+set_active_pcr_banks(struct efi_tcg2_protocol *this, u32 active_pcr_banks)
+{
+	return EFI_UNSUPPORTED;
+}
+
+/**
+ * get_result_of_set_active_pcr_banks() - retrieves the result of a previous
+ *					  set_active_pcr_banks()
+ *
+ * @this:			TCG2 protocol instance
+ * @operation_present:		non-zero value to indicate a
+ *				set_active_pcr_banks operation was
+ *				invoked during last boot
+ * @response:			result value could be returned
+ *
+ * Return:	status code
+ */
+efi_status_t EFIAPI
+get_result_of_set_active_pcr_banks(struct efi_tcg2_protocol *this,
+				   u32 *operation_present, u32 *response)
+{
+	return EFI_UNSUPPORTED;
+}
+
+static const struct efi_tcg2_protocol efi_tcg2_protocol = {
+	.get_capability = get_capability,
+	.get_eventlog = get_eventlog,
+	.hash_log_extend_event = hash_log_extend_event,
+	.submit_command = submit_command,
+	.get_active_pcr_banks = get_active_pcr_banks,
+	.set_active_pcr_banks = set_active_pcr_banks,
+	.get_result_of_set_active_pcr_banks = get_result_of_set_active_pcr_banks,
+};
+
+/**
+ * efi_tcg2_register() - register EFI_TCG2_PROTOCOL
+ *
+ * If a TPM2 device is available, the TPM TCG2 Protocol is registered
+ *
+ * Return:	An error status is only returned if adding the protocol fails.
+ */
+efi_status_t efi_tcg2_register(void)
+{
+	efi_status_t ret;
+	struct udevice *dev;
+	enum tpm_version tpm_ver;
+
+	ret = platform_get_tpm2_device(&dev);
+	if (ret != EFI_SUCCESS)
+		return EFI_SUCCESS;
+
+	tpm_ver = tpm_get_version(dev);
+	if (tpm_ver != TPM_V2) {
+		log_warning("Only TPMv2 supported for EFI_TCG2_PROTOCOL\n");
+		return EFI_SUCCESS;
+	}
+
+	ret = efi_add_protocol(efi_root, &efi_guid_tcg2_protocol,
+			       (void *)&efi_tcg2_protocol);
+	if (ret != EFI_SUCCESS)
+		log_err("Cannot install EFI_TCG2_PROTOCOL\n");
+
+	return ret;
+}
diff --git a/lib/efi_selftest/Makefile b/lib/efi_selftest/Makefile
index aabb743ecb..58fb43fcdf 100644
--- a/lib/efi_selftest/Makefile
+++ b/lib/efi_selftest/Makefile
@@ -55,6 +55,7 @@ obj-$(CONFIG_EFI_LOADER_HII) += efi_selftest_hii.o
 obj-$(CONFIG_EFI_RNG_PROTOCOL) += efi_selftest_rng.o
 obj-$(CONFIG_EFI_GET_TIME) += efi_selftest_rtc.o
 obj-$(CONFIG_EFI_LOAD_FILE2_INITRD) += efi_selftest_load_initrd.o
+obj-$(CONFIG_EFI_TCG2_PROTOCOL) += efi_selftest_tcg2.o
 
 ifeq ($(CONFIG_GENERATE_ACPI_TABLE),)
 obj-y += efi_selftest_fdt.o
diff --git a/lib/efi_selftest/efi_selftest.c b/lib/efi_selftest/efi_selftest.c
index 85e819bdfa..b8eed048c2 100644
--- a/lib/efi_selftest/efi_selftest.c
+++ b/lib/efi_selftest/efi_selftest.c
@@ -38,6 +38,9 @@ void efi_st_exit_boot_services(void)
 	efi_status_t ret;
 	struct efi_mem_desc *memory_map;
 
+	/* Do not detach devices in ExitBootServices. We need the console. */
+	efi_st_keep_devices = true;
+
 	ret = boottime->get_memory_map(&map_size, NULL, &map_key, &desc_size,
 				       &desc_version);
 	if (ret != EFI_BUFFER_TOO_SMALL) {
diff --git a/lib/efi_selftest/efi_selftest_tcg2.c b/lib/efi_selftest/efi_selftest_tcg2.c
new file mode 100644
index 0000000000..1399309cec
--- /dev/null
+++ b/lib/efi_selftest/efi_selftest_tcg2.c
@@ -0,0 +1,75 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * efi_selftest_devicepath
+ *
+ * Copyright (c) 2020 Heinrich Schuchardt <xypron.glpk@gmx.de>
+ *
+ * Test the EFI_TCG2_PROTOCOL
+ */
+
+#include <efi_selftest.h>
+#include <efi_tcg2.h>
+
+static struct efi_boot_services *boottime;
+static const efi_guid_t guid_tcg2 = EFI_TCG2_PROTOCOL_GUID;
+
+/**
+ * efi_st_tcg2_setup() - setup test
+ *
+ * @handle:	handle of the loaded image
+ * @systable:	system table
+ * @return:	status code
+ */
+static int efi_st_tcg2_setup(const efi_handle_t img_handle,
+			     const struct efi_system_table *systable)
+{
+	boottime = systable->boottime;
+
+	return EFI_ST_SUCCESS;
+}
+
+/**
+ * efi_st_tcg2_execute() - execute test
+ *
+ * Call the GetCapability service of the EFI_TCG2_PROTOCOL.
+ *
+ * Return:	status code
+ */
+static int efi_st_tcg2_execute(void)
+{
+	struct efi_tcg2_protocol *tcg2;
+	struct efi_tcg2_boot_service_capability capability;
+	efi_status_t ret;
+
+	ret = boottime->locate_protocol(&guid_tcg2, NULL, (void **)&tcg2);
+	if (ret != EFI_SUCCESS) {
+		efi_st_error("TCG2 protocol is not available.\n");
+		return EFI_ST_FAILURE;
+	}
+	capability.size = sizeof(struct efi_tcg2_boot_service_capability) - 1;
+	ret = tcg2->get_capability(tcg2, &capability);
+	if (ret != EFI_BUFFER_TOO_SMALL) {
+		efi_st_error("tcg2->get_capability on small buffer failed\n");
+		return EFI_ST_FAILURE;
+	}
+	capability.size = sizeof(struct efi_tcg2_boot_service_capability);
+	ret = tcg2->get_capability(tcg2, &capability);
+	if (ret != EFI_SUCCESS) {
+		efi_st_error("tcg2->get_capability failed\n");
+		return EFI_ST_FAILURE;
+	}
+	if (!capability.tpm_present_flag) {
+		efi_st_error("TPM not present\n");
+		return EFI_ST_FAILURE;
+	}
+	efi_st_printf("TPM supports 0x%.8x event logs\n",
+		      capability.supported_event_logs);
+	return EFI_ST_SUCCESS;
+}
+
+EFI_UNIT_TEST(tcg2) = {
+	.name = "tcg2",
+	.phase = EFI_EXECUTE_BEFORE_BOOTTIME_EXIT,
+	.execute = efi_st_tcg2_execute,
+	.setup = efi_st_tcg2_setup,
+};