From patchwork Wed Feb 19 20:10:10 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stuart Yoder X-Patchwork-Id: 13982833 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 404EB21B19E; Wed, 19 Feb 2025 20:10:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739995828; cv=none; b=Kg7oHoOxfpR3H07tcoxm+3UAatrBD2CvEEugwCbhj8zxPmctjaNgMxVBHMLvxp+YhyohQZqwSQR7f1LuMcI6/IeVYnkwBGmHg6DYg3JBWkdewUD4EcC6zTqyGTO1i70e+6KwrTa1TvNSWGDLGsVrla+8DSgG0yP6XqT+ajWPBn0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739995828; c=relaxed/simple; bh=lTA4egH+s//z8kVkW+OC2UPpZpk7ro1d0FnpsCfHul4=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=izAN03NkWLblHlt7H+sMPOHsQRcmBlMmCWZ5kChDOZvhCaFJwthhPEI/Zcq3o/O97zfr6jGzb2OITq1oWj2IcruOeU0G0/Bdpxx2q3bKXet+CVtIiWklRK3/y4Fba7x4lKveVenPxwH4MW5eFldvWZD8OyzV7GPMsLBfItQjPpQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 023E51595; Wed, 19 Feb 2025 12:10:44 -0800 (PST) Received: from beelzebub.ast.arm.com (unknown [10.118.29.240]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 5AB4B3F59E; Wed, 19 Feb 2025 12:10:25 -0800 (PST) From: Stuart Yoder To: linux-integrity@vger.kernel.org, jarkko@kernel.org, peterhuewe@gmx.de, jgg@ziepe.ca, sudeep.holla@arm.com, rafael@kernel.org, lenb@kernel.org Cc: linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v5 1/5] tpm_crb: implement driver compliant to CRB over FF-A Date: Wed, 19 Feb 2025 14:10:10 -0600 Message-Id: <20250219201014.174344-2-stuart.yoder@arm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20250219201014.174344-1-stuart.yoder@arm.com> References: <20250219201014.174344-1-stuart.yoder@arm.com> Precedence: bulk X-Mailing-List: linux-acpi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 The Arm specification TPM Service CRB over FF-A specification defines the FF-A messages to interact with a CRB-based TPM implemented as an FF-A secure partition. Spec URL: https://developer.arm.com/documentation/den0138/latest/ This driver is probed when a TPM Secure Partition is discovered by the FF-A subsystem. It exposes APIs used by the TPM CRB driver to send notifications to the TPM. Acked-by: Sudeep Holla Signed-off-by: Stuart Yoder --- drivers/char/tpm/Kconfig | 9 + drivers/char/tpm/Makefile | 1 + drivers/char/tpm/tpm_crb_ffa.c | 348 +++++++++++++++++++++++++++++++++ drivers/char/tpm/tpm_crb_ffa.h | 25 +++ 4 files changed, 383 insertions(+) create mode 100644 drivers/char/tpm/tpm_crb_ffa.c create mode 100644 drivers/char/tpm/tpm_crb_ffa.h diff --git a/drivers/char/tpm/Kconfig b/drivers/char/tpm/Kconfig index 0fc9a510e059..4c85b8c00b12 100644 --- a/drivers/char/tpm/Kconfig +++ b/drivers/char/tpm/Kconfig @@ -210,6 +210,15 @@ config TCG_CRB from within Linux. To compile this driver as a module, choose M here; the module will be called tpm_crb. +config TCG_ARM_CRB_FFA + tristate "TPM CRB over Arm FF-A Transport" + depends on ARM_FFA_TRANSPORT + default y if (TCG_CRB && ARM_FFA_TRANSPORT) + help + If the Arm FF-A transport is used to access the TPM say Yes. + To compile this driver as a module, choose M here; the module + will be called tpm_crb_ffa. + config TCG_VTPM_PROXY tristate "VTPM Proxy Interface" depends on TCG_TPM diff --git a/drivers/char/tpm/Makefile b/drivers/char/tpm/Makefile index 9bb142c75243..2b004df8c04b 100644 --- a/drivers/char/tpm/Makefile +++ b/drivers/char/tpm/Makefile @@ -42,5 +42,6 @@ obj-$(CONFIG_TCG_IBMVTPM) += tpm_ibmvtpm.o obj-$(CONFIG_TCG_TIS_ST33ZP24) += st33zp24/ obj-$(CONFIG_TCG_XEN) += xen-tpmfront.o obj-$(CONFIG_TCG_CRB) += tpm_crb.o +obj-$(CONFIG_TCG_ARM_CRB_FFA) += tpm_crb_ffa.o obj-$(CONFIG_TCG_VTPM_PROXY) += tpm_vtpm_proxy.o obj-$(CONFIG_TCG_FTPM_TEE) += tpm_ftpm_tee.o diff --git a/drivers/char/tpm/tpm_crb_ffa.c b/drivers/char/tpm/tpm_crb_ffa.c new file mode 100644 index 000000000000..3169a87a56b6 --- /dev/null +++ b/drivers/char/tpm/tpm_crb_ffa.c @@ -0,0 +1,348 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2024 Arm Ltd. + * + * This device driver implements the TPM CRB start method + * as defined in the TPM Service Command Response Buffer + * Interface Over FF-A (DEN0138). + */ + +#define pr_fmt(fmt) "CRB_FFA: " fmt + +#include +#include "tpm_crb_ffa.h" + +/* TPM service function status codes */ +#define CRB_FFA_OK 0x05000001 +#define CRB_FFA_OK_RESULTS_RETURNED 0x05000002 +#define CRB_FFA_NOFUNC 0x8e000001 +#define CRB_FFA_NOTSUP 0x8e000002 +#define CRB_FFA_INVARG 0x8e000005 +#define CRB_FFA_INV_CRB_CTRL_DATA 0x8e000006 +#define CRB_FFA_ALREADY 0x8e000009 +#define CRB_FFA_DENIED 0x8e00000a +#define CRB_FFA_NOMEM 0x8e00000b + +#define CRB_FFA_VERSION_MAJOR 1 +#define CRB_FFA_VERSION_MINOR 0 + +/* version encoding */ +#define CRB_FFA_MAJOR_VERSION_MASK GENMASK(30, 16) +#define CRB_FFA_MINOR_VERSION_MASK GENMASK(15, 0) +#define CRB_FFA_MAJOR_VERSION(x) ((u16)(FIELD_GET(CRB_FFA_MAJOR_VERSION_MASK, (x)))) +#define CRB_FFA_MINOR_VERSION(x) ((u16)(FIELD_GET(CRB_FFA_MINOR_VERSION_MASK, (x)))) + +/* + * Normal world sends requests with FFA_MSG_SEND_DIRECT_REQ and + * responses are returned with FFA_MSG_SEND_DIRECT_RESP for normal + * messages. + * + * All requests with FFA_MSG_SEND_DIRECT_REQ and FFA_MSG_SEND_DIRECT_RESP + * are using the AArch32 SMC calling convention with register usage as + * defined in FF-A specification: + * w0: Function ID (0x8400006F or 0x84000070) + * w1: Source/Destination IDs + * w2: Reserved (MBZ) + * w3-w7: Implementation defined, free to be used below + */ + +/* + * Returns the version of the interface that is available + * Call register usage: + * w3: Not used (MBZ) + * w4: TPM service function ID, CRB_FFA_GET_INTERFACE_VERSION + * w5-w7: Reserved (MBZ) + * + * Return register usage: + * w3: Not used (MBZ) + * w4: TPM service function status + * w5: TPM service interface version + * Bits[31:16]: major version + * Bits[15:0]: minor version + * w6-w7: Reserved (MBZ) + * + * Possible function status codes in register w4: + * CRB_FFA_OK_RESULTS_RETURNED: The version of the interface has been + * returned. + */ +#define CRB_FFA_GET_INTERFACE_VERSION 0x0f000001 + +/* + * Return information on a given feature of the TPM service + * Call register usage: + * w3: Not used (MBZ) + * w4: TPM service function ID, CRB_FFA_START + * w5: Start function qualifier + * Bits[31:8] (MBZ) + * Bits[7:0] + * 0: Notifies TPM that a command is ready to be processed + * 1: Notifies TPM that a locality request is ready to be processed + * w6: TPM locality, one of 0..4 + * -If the start function qualifier is 0, identifies the locality + * from where the command originated. + * -If the start function qualifier is 1, identifies the locality + * of the locality request + * w6-w7: Reserved (MBZ) + * + * Return register usage: + * w3: Not used (MBZ) + * w4: TPM service function status + * w5-w7: Reserved (MBZ) + * + * Possible function status codes in register w4: + * CRB_FFA_OK: the TPM service has been notified successfully + * CRB_FFA_INVARG: one or more arguments are not valid + * CRB_FFA_INV_CRB_CTRL_DATA: CRB control data or locality control + * data at the given TPM locality is not valid + * CRB_FFA_DENIED: the TPM has previously disabled locality requests and + * command processing at the given locality + */ +#define CRB_FFA_START 0x0f000201 + +struct tpm_crb_ffa { + struct ffa_device *ffa_dev; + u16 major_version; + u16 minor_version; + /* lock to protect sending of FF-A messages: */ + struct mutex msg_data_lock; + struct ffa_send_direct_data direct_msg_data; +}; + +static struct tpm_crb_ffa *tpm_crb_ffa; + +static int tpm_crb_ffa_to_linux_errno(int errno) +{ + int rc; + + switch (errno) { + case CRB_FFA_OK: + rc = 0; + break; + case CRB_FFA_OK_RESULTS_RETURNED: + rc = 0; + break; + case CRB_FFA_NOFUNC: + rc = -ENOENT; + break; + case CRB_FFA_NOTSUP: + rc = -EPERM; + break; + case CRB_FFA_INVARG: + rc = -EINVAL; + break; + case CRB_FFA_INV_CRB_CTRL_DATA: + rc = -ENOEXEC; + break; + case CRB_FFA_ALREADY: + rc = -EEXIST; + break; + case CRB_FFA_DENIED: + rc = -EACCES; + break; + case CRB_FFA_NOMEM: + rc = -ENOMEM; + break; + default: + rc = -EINVAL; + } + + return rc; +} + +/** + * tpm_crb_ffa_init - called by the CRB driver to do any needed initialization + * + * This function is called by the tpm_crb driver during the tpm_crb + * driver's initialization. If the tpm_crb_ffa has not been probed + * yet, returns -ENOENT in order to force a retry. If th ffa_crb + * driver had been probed but failed with an error, returns -ENODEV + * in order to prevent further retries. + * + * Return: 0 on success, negative error code on failure. + */ +int tpm_crb_ffa_init(void) +{ + if (!tpm_crb_ffa) + return -ENOENT; + + if (IS_ERR_VALUE(tpm_crb_ffa)) + return -ENODEV; + + return 0; +} +EXPORT_SYMBOL_GPL(tpm_crb_ffa_init); + +static int __tpm_crb_ffa_send_recieve(unsigned long func_id, + unsigned long a0, + unsigned long a1, + unsigned long a2) +{ + const struct ffa_msg_ops *msg_ops; + int ret; + + if (!tpm_crb_ffa) + return -ENOENT; + + msg_ops = tpm_crb_ffa->ffa_dev->ops->msg_ops; + + memset(&tpm_crb_ffa->direct_msg_data, 0x00, + sizeof(struct ffa_send_direct_data)); + + tpm_crb_ffa->direct_msg_data.data1 = func_id; + tpm_crb_ffa->direct_msg_data.data2 = a0; + tpm_crb_ffa->direct_msg_data.data3 = a1; + tpm_crb_ffa->direct_msg_data.data4 = a2; + + ret = msg_ops->sync_send_receive(tpm_crb_ffa->ffa_dev, + &tpm_crb_ffa->direct_msg_data); + if (!ret) + ret = tpm_crb_ffa_to_linux_errno(tpm_crb_ffa->direct_msg_data.data1); + + return ret; +} + +/** + * tpm_crb_ffa_get_interface_version() - gets the ABI version of the TPM service + * @major: Pointer to caller-allocated buffer to hold the major version + * number the ABI + * @minor: Pointer to caller-allocated buffer to hold the minor version + * number the ABI + * + * Returns the major and minor version of the ABI of the FF-A based TPM. + * Allows the caller to evaluate its compatibility with the version of + * the ABI. + * + * Return: 0 on success, negative error code on failure. + */ +int tpm_crb_ffa_get_interface_version(u16 *major, u16 *minor) +{ + int rc; + + if (!tpm_crb_ffa) + return -ENOENT; + + if (IS_ERR_VALUE(tpm_crb_ffa)) + return -ENODEV; + + if (!major || !minor) + return -EINVAL; + + guard(mutex)(&tpm_crb_ffa->msg_data_lock); + + rc = __tpm_crb_ffa_send_recieve(CRB_FFA_GET_INTERFACE_VERSION, 0x00, 0x00, 0x00); + if (!rc) { + *major = CRB_FFA_MAJOR_VERSION(tpm_crb_ffa->direct_msg_data.data2); + *minor = CRB_FFA_MINOR_VERSION(tpm_crb_ffa->direct_msg_data.data2); + } + + return rc; +} +EXPORT_SYMBOL_GPL(tpm_crb_ffa_get_interface_version); + +/** + * tpm_crb_ffa_start() - signals the TPM that a field has changed in the CRB + * @request_type: Identifies whether the change to the CRB is in the command + * fields or locality fields. + * @locality: Specifies the locality number. + * + * Used by the CRB driver + * that might be useful to those using or modifying it. Begins with + * empty comment line, and may include additional embedded empty + * comment lines. + * + * Return: 0 on success, negative error code on failure. + */ +int tpm_crb_ffa_start(int request_type, int locality) +{ + if (!tpm_crb_ffa) + return -ENOENT; + + if (IS_ERR_VALUE(tpm_crb_ffa)) + return -ENODEV; + + guard(mutex)(&tpm_crb_ffa->msg_data_lock); + + return __tpm_crb_ffa_send_recieve(CRB_FFA_START, request_type, locality, 0x00); +} +EXPORT_SYMBOL_GPL(tpm_crb_ffa_start); + +static int tpm_crb_ffa_probe(struct ffa_device *ffa_dev) +{ + struct tpm_crb_ffa *p; + int rc; + + /* only one instance of a TPM partition is supported */ + if (tpm_crb_ffa && !IS_ERR_VALUE(tpm_crb_ffa)) + return -EEXIST; + + tpm_crb_ffa = ERR_PTR(-ENODEV); // set tpm_crb_ffa so we can detect probe failure + + if (!ffa_partition_supports_direct_recv(ffa_dev)) { + pr_err("TPM partition doesn't support direct message receive.\n"); + return -EINVAL; + } + + p = kzalloc(sizeof(*tpm_crb_ffa), GFP_KERNEL); + if (!p) + return -ENOMEM; + tpm_crb_ffa = p; + + mutex_init(&tpm_crb_ffa->msg_data_lock); + tpm_crb_ffa->ffa_dev = ffa_dev; + ffa_dev_set_drvdata(ffa_dev, tpm_crb_ffa); + + /* if TPM is aarch32 use 32-bit SMCs */ + if (!ffa_partition_check_property(ffa_dev, FFA_PARTITION_AARCH64_EXEC)) + ffa_dev->ops->msg_ops->mode_32bit_set(ffa_dev); + + /* verify compatibility of TPM service version number */ + rc = tpm_crb_ffa_get_interface_version(&tpm_crb_ffa->major_version, + &tpm_crb_ffa->minor_version); + if (rc) { + pr_err("failed to get crb interface version. rc:%d", rc); + goto out; + } + + pr_info("ABI version %u.%u", tpm_crb_ffa->major_version, + tpm_crb_ffa->minor_version); + + if (tpm_crb_ffa->major_version != CRB_FFA_VERSION_MAJOR || + (tpm_crb_ffa->minor_version > 0 && + tpm_crb_ffa->minor_version < CRB_FFA_VERSION_MINOR)) { + pr_err("Incompatible ABI version"); + goto out; + } + + return 0; + +out: + kfree(tpm_crb_ffa); + tpm_crb_ffa = ERR_PTR(-ENODEV); + return -EINVAL; +} + +static void tpm_crb_ffa_remove(struct ffa_device *ffa_dev) +{ + kfree(tpm_crb_ffa); + tpm_crb_ffa = NULL; +} + +static const struct ffa_device_id tpm_crb_ffa_device_id[] = { + /* 17b862a4-1806-4faf-86b3-089a58353861 */ + { UUID_INIT(0x17b862a4, 0x1806, 0x4faf, + 0x86, 0xb3, 0x08, 0x9a, 0x58, 0x35, 0x38, 0x61) }, + {} +}; + +static struct ffa_driver tpm_crb_ffa_driver = { + .name = "ffa-crb", + .probe = tpm_crb_ffa_probe, + .remove = tpm_crb_ffa_remove, + .id_table = tpm_crb_ffa_device_id, +}; + +module_ffa_driver(tpm_crb_ffa_driver); + +MODULE_AUTHOR("Arm"); +MODULE_DESCRIPTION("TPM CRB FFA driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/char/tpm/tpm_crb_ffa.h b/drivers/char/tpm/tpm_crb_ffa.h new file mode 100644 index 000000000000..23a9b93287a1 --- /dev/null +++ b/drivers/char/tpm/tpm_crb_ffa.h @@ -0,0 +1,25 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2024 Arm Ltd. + * + * This device driver implements the TPM CRB start method + * as defined in the TPM Service Command Response Buffer + * Interface Over FF-A (DEN0138). + */ +#ifndef _TPM_CRB_FFA_H +#define _TPM_CRB_FFA_H + +#if IS_ENABLED(CONFIG_TCG_ARM_CRB_FFA) +int tpm_crb_ffa_init(void); +int tpm_crb_ffa_get_interface_version(u16 *major, u16 *minor); +int tpm_crb_ffa_start(int request_type, int locality); +#else +static inline int tpm_crb_ffa_init(void) { return 0; } +static inline int tpm_crb_ffa_get_interface_version(u16 *major, u16 *minor) { return 0; } +static inline int tpm_crb_ffa_start(int request_type, int locality) { return 0; } +#endif + +#define CRB_FFA_START_TYPE_COMMAND 0 +#define CRB_FFA_START_TYPE_LOCALITY_REQUEST 1 + +#endif From patchwork Wed Feb 19 20:10:11 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stuart Yoder X-Patchwork-Id: 13982834 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id A4E4421B9E9; Wed, 19 Feb 2025 20:10:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739995828; cv=none; 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Wed, 19 Feb 2025 12:10:44 -0800 (PST) Received: from beelzebub.ast.arm.com (unknown [10.118.29.240]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id B0BDB3F59E; Wed, 19 Feb 2025 12:10:25 -0800 (PST) From: Stuart Yoder To: linux-integrity@vger.kernel.org, jarkko@kernel.org, peterhuewe@gmx.de, jgg@ziepe.ca, sudeep.holla@arm.com, rafael@kernel.org, lenb@kernel.org Cc: linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v5 2/5] tpm_crb: clean-up and refactor check for idle support Date: Wed, 19 Feb 2025 14:10:11 -0600 Message-Id: <20250219201014.174344-3-stuart.yoder@arm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20250219201014.174344-1-stuart.yoder@arm.com> References: <20250219201014.174344-1-stuart.yoder@arm.com> Precedence: bulk X-Mailing-List: linux-acpi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Refactor TPM idle check to tpm_crb_has_idle(), and reduce paraentheses usage in start method checks Signed-off-by: Stuart Yoder Reviewed-by: Jarkko Sakkinen --- drivers/char/tpm/tpm_crb.c | 36 +++++++++++++++++++++--------------- 1 file changed, 21 insertions(+), 15 deletions(-) diff --git a/drivers/char/tpm/tpm_crb.c b/drivers/char/tpm/tpm_crb.c index ea085b14ab7c..31db879f1324 100644 --- a/drivers/char/tpm/tpm_crb.c +++ b/drivers/char/tpm/tpm_crb.c @@ -115,6 +115,16 @@ struct tpm2_crb_pluton { u64 reply_addr; }; +/* + * Returns true if the start method supports idle. + */ +static inline bool tpm_crb_has_idle(u32 start_method) +{ + return start_method == ACPI_TPM2_START_METHOD || + start_method == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD || + start_method == ACPI_TPM2_COMMAND_BUFFER_WITH_ARM_SMC; +} + static bool crb_wait_for_reg_32(u32 __iomem *reg, u32 mask, u32 value, unsigned long timeout) { @@ -173,9 +183,7 @@ static int __crb_go_idle(struct device *dev, struct crb_priv *priv) { int rc; - if ((priv->sm == ACPI_TPM2_START_METHOD) || - (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD) || - (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_ARM_SMC)) + if (!tpm_crb_has_idle(priv->sm)) return 0; iowrite32(CRB_CTRL_REQ_GO_IDLE, &priv->regs_t->ctrl_req); @@ -222,9 +230,7 @@ static int __crb_cmd_ready(struct device *dev, struct crb_priv *priv) { int rc; - if ((priv->sm == ACPI_TPM2_START_METHOD) || - (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD) || - (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_ARM_SMC)) + if (!tpm_crb_has_idle(priv->sm)) return 0; iowrite32(CRB_CTRL_REQ_CMD_READY, &priv->regs_t->ctrl_req); @@ -423,13 +429,13 @@ static int crb_send(struct tpm_chip *chip, u8 *buf, size_t len) * report only ACPI start but in practice seems to require both * CRB start, hence invoking CRB start method if hid == MSFT0101. */ - if ((priv->sm == ACPI_TPM2_COMMAND_BUFFER) || - (priv->sm == ACPI_TPM2_MEMORY_MAPPED) || - (!strcmp(priv->hid, "MSFT0101"))) + if (priv->sm == ACPI_TPM2_COMMAND_BUFFER || + priv->sm == ACPI_TPM2_MEMORY_MAPPED || + !strcmp(priv->hid, "MSFT0101")) iowrite32(CRB_START_INVOKE, &priv->regs_t->ctrl_start); - if ((priv->sm == ACPI_TPM2_START_METHOD) || - (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD)) + if (priv->sm == ACPI_TPM2_START_METHOD || + priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD) rc = crb_do_acpi_start(chip); if (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_ARM_SMC) { @@ -449,8 +455,8 @@ static void crb_cancel(struct tpm_chip *chip) iowrite32(CRB_CANCEL_INVOKE, &priv->regs_t->ctrl_cancel); - if (((priv->sm == ACPI_TPM2_START_METHOD) || - (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD)) && + if ((priv->sm == ACPI_TPM2_START_METHOD || + priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD) && crb_do_acpi_start(chip)) dev_err(&chip->dev, "ACPI Start failed\n"); } @@ -609,8 +615,8 @@ static int crb_map_io(struct acpi_device *device, struct crb_priv *priv, * the control area, as one nice sane region except for some older * stuff that puts the control area outside the ACPI IO region. */ - if ((priv->sm == ACPI_TPM2_COMMAND_BUFFER) || - (priv->sm == ACPI_TPM2_MEMORY_MAPPED)) { + if (priv->sm == ACPI_TPM2_COMMAND_BUFFER || + priv->sm == ACPI_TPM2_MEMORY_MAPPED) { if (iores && buf->control_address == iores->start + sizeof(*priv->regs_h)) From patchwork Wed Feb 19 20:10:12 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stuart Yoder X-Patchwork-Id: 13982835 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 4D92E22B5A5; 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dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id B96B51682; Wed, 19 Feb 2025 12:10:44 -0800 (PST) Received: from beelzebub.ast.arm.com (unknown [10.118.29.240]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 1292C3F59E; Wed, 19 Feb 2025 12:10:26 -0800 (PST) From: Stuart Yoder To: linux-integrity@vger.kernel.org, jarkko@kernel.org, peterhuewe@gmx.de, jgg@ziepe.ca, sudeep.holla@arm.com, rafael@kernel.org, lenb@kernel.org Cc: linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v5 3/5] ACPICA: add start method for Arm FF-A Date: Wed, 19 Feb 2025 14:10:12 -0600 Message-Id: <20250219201014.174344-4-stuart.yoder@arm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20250219201014.174344-1-stuart.yoder@arm.com> References: <20250219201014.174344-1-stuart.yoder@arm.com> Precedence: bulk X-Mailing-List: linux-acpi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Add TPM start method for Arm FF-A defined in the TCG ACPI specification v1.4. Link: https://github.com/acpica/acpica/pull/1000 Reviewed-by: Jarkko Sakkinen Signed-off-by: Stuart Yoder --- include/acpi/actbl3.h | 1 + 1 file changed, 1 insertion(+) diff --git a/include/acpi/actbl3.h b/include/acpi/actbl3.h index 5cd755143b7d..a97b1dbab975 100644 --- a/include/acpi/actbl3.h +++ b/include/acpi/actbl3.h @@ -466,6 +466,7 @@ struct acpi_tpm2_phy { #define ACPI_TPM2_COMMAND_BUFFER_WITH_ARM_SMC 11 /* V1.2 Rev 8 */ #define ACPI_TPM2_RESERVED 12 #define ACPI_TPM2_COMMAND_BUFFER_WITH_PLUTON 13 +#define ACPI_TPM2_CRB_WITH_ARM_FFA 15 /* Optional trailer appears after any start_method subtables */ From patchwork Wed Feb 19 20:10:13 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stuart Yoder X-Patchwork-Id: 13982836 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 4D8CE22A813; Wed, 19 Feb 2025 20:10:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739995829; cv=none; b=BU3Zi3arg1e1Q+W1doOiD6ST2mCpa94KRwafHq6+LX6zHkN/ths+/Up4DwDLcExeajOOCjzUtI/gjIO76dDXY4cjxZeaUeAOy/cFSp+7aI/EMlmaCljrDvjcJgro8rZmSaFyTK35rSmsYB/y/JvtA7LomGWDAWduzEdJ1YdoeyU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739995829; c=relaxed/simple; bh=1l6FdATWXGuk0RQ5TmGqiYIkoGLZjw0XID4zJjJiwfc=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=h6N0CbzHC+KSuCaX0FcNCBsUuqAuLDWr5EH95TCuXzHiaX3rdQsSB7sD11iDarN9PAaaVynQpwsIVbZCzReFi77NQVGt21OvBIQndcbmKUty6+2FGcmL7AfOkJnxDKYfyJYL1zduIB9uRheUmykSR1MQnHSbGmJBJ6R5n/T/rE8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 1B60F1A32; Wed, 19 Feb 2025 12:10:45 -0800 (PST) Received: from beelzebub.ast.arm.com (unknown [10.118.29.240]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 736C93F59E; Wed, 19 Feb 2025 12:10:26 -0800 (PST) From: Stuart Yoder To: linux-integrity@vger.kernel.org, jarkko@kernel.org, peterhuewe@gmx.de, jgg@ziepe.ca, sudeep.holla@arm.com, rafael@kernel.org, lenb@kernel.org Cc: linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v5 4/5] tpm_crb: add support for the Arm FF-A start method Date: Wed, 19 Feb 2025 14:10:13 -0600 Message-Id: <20250219201014.174344-5-stuart.yoder@arm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20250219201014.174344-1-stuart.yoder@arm.com> References: <20250219201014.174344-1-stuart.yoder@arm.com> Precedence: bulk X-Mailing-List: linux-acpi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 The TCG ACPI spec v1.4 defines a start method for the TPMs implemented with the Arm CRB over FF-A ABI. Add support for the FF-A start method, and use interfaces provided by the ffa_crb driver to interact with the FF-A based TPM. Reviewed-by: Jarkko Sakkinen Signed-off-by: Stuart Yoder --- drivers/char/tpm/tpm_crb.c | 71 +++++++++++++++++++++++++++++++++++--- 1 file changed, 66 insertions(+), 5 deletions(-) diff --git a/drivers/char/tpm/tpm_crb.c b/drivers/char/tpm/tpm_crb.c index 31db879f1324..2a57650ba9b4 100644 --- a/drivers/char/tpm/tpm_crb.c +++ b/drivers/char/tpm/tpm_crb.c @@ -19,6 +19,7 @@ #ifdef CONFIG_ARM64 #include #endif +#include "tpm_crb_ffa.h" #include "tpm.h" #define ACPI_SIG_TPM2 "TPM2" @@ -100,6 +101,8 @@ struct crb_priv { u32 smc_func_id; u32 __iomem *pluton_start_addr; u32 __iomem *pluton_reply_addr; + u8 ffa_flags; + u8 ffa_attributes; }; struct tpm2_crb_smc { @@ -110,6 +113,14 @@ struct tpm2_crb_smc { u32 smc_func_id; }; +/* CRB over FFA start method parameters in TCG2 ACPI table */ +struct tpm2_crb_ffa { + u8 flags; + u8 attributes; + u16 partition_id; + u8 reserved[8]; +}; + struct tpm2_crb_pluton { u64 start_addr; u64 reply_addr; @@ -122,7 +133,8 @@ static inline bool tpm_crb_has_idle(u32 start_method) { return start_method == ACPI_TPM2_START_METHOD || start_method == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD || - start_method == ACPI_TPM2_COMMAND_BUFFER_WITH_ARM_SMC; + start_method == ACPI_TPM2_COMMAND_BUFFER_WITH_ARM_SMC || + start_method == ACPI_TPM2_CRB_WITH_ARM_FFA; } static bool crb_wait_for_reg_32(u32 __iomem *reg, u32 mask, u32 value, @@ -261,13 +273,20 @@ static int crb_cmd_ready(struct tpm_chip *chip) static int __crb_request_locality(struct device *dev, struct crb_priv *priv, int loc) { - u32 value = CRB_LOC_STATE_LOC_ASSIGNED | - CRB_LOC_STATE_TPM_REG_VALID_STS; + u32 value = CRB_LOC_STATE_LOC_ASSIGNED | CRB_LOC_STATE_TPM_REG_VALID_STS; + int rc; if (!priv->regs_h) return 0; iowrite32(CRB_LOC_CTRL_REQUEST_ACCESS, &priv->regs_h->loc_ctrl); + + if (priv->sm == ACPI_TPM2_CRB_WITH_ARM_FFA) { + rc = tpm_crb_ffa_start(CRB_FFA_START_TYPE_LOCALITY_REQUEST, loc); + if (rc) + return rc; + } + if (!crb_wait_for_reg_32(&priv->regs_h->loc_state, value, value, TPM2_TIMEOUT_C)) { dev_warn(dev, "TPM_LOC_STATE_x.requestAccess timed out\n"); @@ -287,14 +306,21 @@ static int crb_request_locality(struct tpm_chip *chip, int loc) static int __crb_relinquish_locality(struct device *dev, struct crb_priv *priv, int loc) { - u32 mask = CRB_LOC_STATE_LOC_ASSIGNED | - CRB_LOC_STATE_TPM_REG_VALID_STS; + u32 mask = CRB_LOC_STATE_LOC_ASSIGNED | CRB_LOC_STATE_TPM_REG_VALID_STS; u32 value = CRB_LOC_STATE_TPM_REG_VALID_STS; + int rc; if (!priv->regs_h) return 0; iowrite32(CRB_LOC_CTRL_RELINQUISH, &priv->regs_h->loc_ctrl); + + if (priv->sm == ACPI_TPM2_CRB_WITH_ARM_FFA) { + rc = tpm_crb_ffa_start(CRB_FFA_START_TYPE_LOCALITY_REQUEST, loc); + if (rc) + return rc; + } + if (!crb_wait_for_reg_32(&priv->regs_h->loc_state, mask, value, TPM2_TIMEOUT_C)) { dev_warn(dev, "TPM_LOC_STATE_x.Relinquish timed out\n"); @@ -443,6 +469,11 @@ static int crb_send(struct tpm_chip *chip, u8 *buf, size_t len) rc = tpm_crb_smc_start(&chip->dev, priv->smc_func_id); } + if (priv->sm == ACPI_TPM2_CRB_WITH_ARM_FFA) { + iowrite32(CRB_START_INVOKE, &priv->regs_t->ctrl_start); + rc = tpm_crb_ffa_start(CRB_FFA_START_TYPE_COMMAND, chip->locality); + } + if (rc) return rc; @@ -452,6 +483,7 @@ static int crb_send(struct tpm_chip *chip, u8 *buf, size_t len) static void crb_cancel(struct tpm_chip *chip) { struct crb_priv *priv = dev_get_drvdata(&chip->dev); + int rc; iowrite32(CRB_CANCEL_INVOKE, &priv->regs_t->ctrl_cancel); @@ -459,6 +491,12 @@ static void crb_cancel(struct tpm_chip *chip) priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD) && crb_do_acpi_start(chip)) dev_err(&chip->dev, "ACPI Start failed\n"); + + if (priv->sm == ACPI_TPM2_CRB_WITH_ARM_FFA) { + rc = tpm_crb_ffa_start(CRB_FFA_START_TYPE_COMMAND, chip->locality); + if (rc) + dev_err(&chip->dev, "FF-A Start failed\n"); + } } static bool crb_req_canceled(struct tpm_chip *chip, u8 status) @@ -616,6 +654,7 @@ static int crb_map_io(struct acpi_device *device, struct crb_priv *priv, * stuff that puts the control area outside the ACPI IO region. */ if (priv->sm == ACPI_TPM2_COMMAND_BUFFER || + priv->sm == ACPI_TPM2_CRB_WITH_ARM_FFA || priv->sm == ACPI_TPM2_MEMORY_MAPPED) { if (iores && buf->control_address == iores->start + @@ -737,6 +776,7 @@ static int crb_acpi_add(struct acpi_device *device) struct tpm_chip *chip; struct device *dev = &device->dev; struct tpm2_crb_smc *crb_smc; + struct tpm2_crb_ffa *crb_ffa; struct tpm2_crb_pluton *crb_pluton; acpi_status status; u32 sm; @@ -775,6 +815,27 @@ static int crb_acpi_add(struct acpi_device *device) priv->smc_func_id = crb_smc->smc_func_id; } + if (sm == ACPI_TPM2_CRB_WITH_ARM_FFA) { + if (buf->header.length < (sizeof(*buf) + sizeof(*crb_ffa))) { + dev_err(dev, + FW_BUG "TPM2 ACPI table has wrong size %u for start method type %d\n", + buf->header.length, + ACPI_TPM2_CRB_WITH_ARM_FFA); + rc = -EINVAL; + goto out; + } + crb_ffa = ACPI_ADD_PTR(struct tpm2_crb_ffa, buf, sizeof(*buf)); + priv->ffa_flags = crb_ffa->flags; + priv->ffa_attributes = crb_ffa->attributes; + rc = tpm_crb_ffa_init(); + if (rc) { + if (rc == -ENOENT) { // FF-A driver is not available yet + rc = -EPROBE_DEFER; + } + goto out; + } + } + if (sm == ACPI_TPM2_COMMAND_BUFFER_WITH_PLUTON) { if (buf->header.length < (sizeof(*buf) + sizeof(*crb_pluton))) { dev_err(dev, From patchwork Wed Feb 19 20:10:14 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stuart Yoder X-Patchwork-Id: 13982837 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id B144222DFE3; 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dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 7167C2050; Wed, 19 Feb 2025 12:10:45 -0800 (PST) Received: from beelzebub.ast.arm.com (unknown [10.118.29.240]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id C97AD3F59E; Wed, 19 Feb 2025 12:10:26 -0800 (PST) From: Stuart Yoder To: linux-integrity@vger.kernel.org, jarkko@kernel.org, peterhuewe@gmx.de, jgg@ziepe.ca, sudeep.holla@arm.com, rafael@kernel.org, lenb@kernel.org Cc: linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v5 5/5] Documentation: tpm: add documentation for the CRB FF-A interface Date: Wed, 19 Feb 2025 14:10:14 -0600 Message-Id: <20250219201014.174344-6-stuart.yoder@arm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20250219201014.174344-1-stuart.yoder@arm.com> References: <20250219201014.174344-1-stuart.yoder@arm.com> Precedence: bulk X-Mailing-List: linux-acpi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Add documentation providing details of how the CRB driver interacts with FF-A. Signed-off-by: Stuart Yoder Reviewed-by: Jarkko Sakkinen --- Documentation/security/tpm/tpm_ffa_crb.rst | 65 ++++++++++++++++++++++ 1 file changed, 65 insertions(+) create mode 100644 Documentation/security/tpm/tpm_ffa_crb.rst diff --git a/Documentation/security/tpm/tpm_ffa_crb.rst b/Documentation/security/tpm/tpm_ffa_crb.rst new file mode 100644 index 000000000000..0184193da3c7 --- /dev/null +++ b/Documentation/security/tpm/tpm_ffa_crb.rst @@ -0,0 +1,65 @@ +.. SPDX-License-Identifier: GPL-2.0 + +======================== +TPM CRB over FF-A Driver +======================== + +The TPM Command Response Buffer (CRB) interface is a standard TPM interface +defined in the TCG PC Client Platform TPM Profile (PTP) Specification [1]_. +The CRB provides a structured set of control registers a client uses when +interacting with a TPM as well as a data buffer for storing TPM commands and +responses. A CRB interface can be implemented in: + +- hardware registers in a discrete TPM chip + +- in memory for a TPM running in isolated environment where shared memory + allows a client to interact with the TPM + +The Firmware Framework for Arm A-profile (FF-A) [2]_ is a specification +that defines interfaces and protocols for the following purposes: + +- Compartmentalize firmware into software partitions that run in the Arm + Secure world environment (also know as TrustZone) + +- Provide a standard interface for software components in the Non-secure + state, for example OS and Hypervisors, to communicate with this firmware. + +A TPM can be implemented as an FF-A secure service. This could be a firmware +TPM or could potentially be a TPM service that acts as a proxy to a discrete +TPM chip. An FF-A based TPM abstracts hardware details (e.g. bus controller +and chip selects) away from the OS and can protect locality 4 from access +by an OS. The TCG-defined CRB interface is used by clients to interact +with the TPM service. + +The Arm TPM Service Command Response Buffer Interface Over FF-A [3]_ +specification defines FF-A messages that can be used by a client to signal +when updates have been made to the CRB. + +How the Linux CRB driver interacts with FF-A is summarized below: + +- The tpm_crb_ffa driver registers with the FF-A subsystem in the kernel + with an architected TPM service UUID defined in the CRB over FF-A spec. + +- If a TPM service is discovered by FF-A, the probe() function in the + tpm_crb_ffa driver runs, and the driver initializes. + +- The probing and initialization of the Linux CRB driver is triggered + by the discovery of a TPM advertised via ACPI. The CRB driver can + detect the type of TPM through the ACPI 'start' method. The start + method for Arm FF-A was defined in TCG ACPI v1.4 [4]_. + +- When the CRB driver performs its normal functions such as signaling 'start' + and locality request/relinquish it invokes the tpm_crb_ffa_start() funnction + in the tpm_crb_ffa driver which handles the FF-A messaging to the TPM. + +References +========== + +.. [1] **TCG PC Client Platform TPM Profile (PTP) Specification** + https://trustedcomputinggroup.org/resource/pc-client-platform-tpm-profile-ptp-specification/ +.. [2] **Arm Firmware Framework for Arm A-profile (FF-A)** + https://developer.arm.com/documentation/den0077/latest/ +.. [3] **Arm TPM Service Command Response Buffer Interface Over FF-A** + https://developer.arm.com/documentation/den0138/latest/ +.. [4] **TCG ACPI Specification** + https://trustedcomputinggroup.org/resource/tcg-acpi-specification/