From patchwork Thu Sep 15 08:14:51 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sughosh Ganu X-Patchwork-Id: 606202 Delivered-To: patch@linaro.org Received: by 2002:ab3:1c02:0:b0:1e7:4ce8:c350 with SMTP id u2csp147622lth; Thu, 15 Sep 2022 01:18:37 -0700 (PDT) X-Google-Smtp-Source: AA6agR5KY4yVpeQUWYrqxn0YENcnjEarcHuBlIcH8QO9nMiIixRhX/DqzR65kHQ6AwpR5od9zGOj X-Received: by 2002:aa7:d150:0:b0:44e:3c06:d719 with SMTP id r16-20020aa7d150000000b0044e3c06d719mr34457403edo.265.1663229917729; Thu, 15 Sep 2022 01:18:37 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1663229917; cv=none; d=google.com; s=arc-20160816; b=GFWMHY4C/7L4JDhzAtrDo3ZHUSG6wWgc9fwBG0JbJSMtfggMedfQB+B2OrzESz/IeR Omo/aqGmArTfa37M+U8JU1T44C1HY+TP96r8j/2N9lALXSPVOC9zEMZWbYsxCTX7JY81 lOUH7NJdVcKgppmnEd2Ab9VI7tKqbsmAlGt7a8F1+4FMYQn4bY1VUOSP2+iabLbMNpzW wmK/zMmUTBbgsoG1HJ1OTNuL6y6yyqvJ5nL5Cus2zRummh19r5Mul5yHWjhzkleFsN8F clVSFN2gQDBd1ZUdaFh8Wa5X5ABBHtlar2xEGEC2AsqFb35r+6UyGkKyugk0pimLiTxj jBFA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=sender:errors-to:list-subscribe:list-help:list-post:list-archive :list-unsubscribe:list-id:precedence:content-transfer-encoding :mime-version:references:in-reply-to:message-id:date:subject:cc:to :from; bh=Ut2jl3uPvEZlunipk/6aql2N419uC6wusIRqEwV1blk=; b=X5CLajnIcipBbXJzaJp1ZeYCkBmCIpBh60TS0I6X1sx6sZGunQRDWSGN99bzoIjmL/ Qst+99xy4xx8f2XI2VOJ4Pg1flaOtGWoqmeMNAwdX9aCdCoIbooSZQ4xkS6Dg/qYhgMr SwkRS9uIqgCzjRkKWHirVo3jkQC1vgGmkKZ0kso6MTu6dE6PSv8OXixTtNvDK7HDn3Ks oMPPu3jFnyNb/YztZ43+hb1iUxkl7UMWD/pSMFDZVuO/dWQLLHdlnmTwITcIXuVFAfme AzNy0Az/A5Zo4Msy4UwcBEysmKbjYyIS6cK3O/QGliQfavT9Gbbn4c+GATOqjNcavKzQ kKsA== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of u-boot-bounces@lists.denx.de designates 85.214.62.61 as permitted sender) smtp.mailfrom=u-boot-bounces@lists.denx.de; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=linaro.org Return-Path: Received: from phobos.denx.de (phobos.denx.de. [85.214.62.61]) by mx.google.com with ESMTPS id hp13-20020a1709073e0d00b0077c98c62b00si10625885ejc.654.2022.09.15.01.18.37 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 15 Sep 2022 01:18:37 -0700 (PDT) Received-SPF: pass (google.com: domain of u-boot-bounces@lists.denx.de designates 85.214.62.61 as permitted sender) client-ip=85.214.62.61; Authentication-Results: mx.google.com; spf=pass (google.com: domain of u-boot-bounces@lists.denx.de designates 85.214.62.61 as permitted sender) smtp.mailfrom=u-boot-bounces@lists.denx.de; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=linaro.org Received: from h2850616.stratoserver.net (localhost [IPv6:::1]) by phobos.denx.de (Postfix) with ESMTP id 2A80784BB1; Thu, 15 Sep 2022 10:16:30 +0200 (CEST) Authentication-Results: phobos.denx.de; dmarc=fail (p=none dis=none) header.from=linaro.org Authentication-Results: phobos.denx.de; spf=pass smtp.mailfrom=u-boot-bounces@lists.denx.de Received: by phobos.denx.de (Postfix, from userid 109) id BA5F784BCC; Thu, 15 Sep 2022 10:16:26 +0200 (CEST) X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on phobos.denx.de X-Spam-Level: X-Spam-Status: No, score=-1.2 required=5.0 tests=BAYES_00,SPF_HELO_NONE, SPF_SOFTFAIL,T_SCC_BODY_TEXT_LINE autolearn=no autolearn_force=no version=3.4.2 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by phobos.denx.de (Postfix) with ESMTP id 0562484BB3 for ; Thu, 15 Sep 2022 10:16:23 +0200 (CEST) Authentication-Results: phobos.denx.de; dmarc=fail (p=none dis=none) header.from=linaro.org Authentication-Results: phobos.denx.de; spf=fail smtp.mailfrom=sughosh.ganu@linaro.org 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 E7F111692; Thu, 15 Sep 2022 01:16:28 -0700 (PDT) Received: from a076522.blr.arm.com (a076522.blr.arm.com [10.162.16.44]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id D4C4F3F73B; Thu, 15 Sep 2022 01:16:18 -0700 (PDT) From: Sughosh Ganu To: u-boot@lists.denx.de Cc: Heinrich Schuchardt , Ilias Apalodimas , Takahiro Akashi , Patrick Delaunay , Patrice Chotard , Simon Glass , Bin Meng , Tom Rini , Etienne Carriere , Michal Simek , Jassi Brar , Sughosh Ganu Subject: [PATCH v10 15/15] FWU: doc: Add documentation for the FWU feature Date: Thu, 15 Sep 2022 13:44:51 +0530 Message-Id: <20220915081451.633983-16-sughosh.ganu@linaro.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220915081451.633983-1-sughosh.ganu@linaro.org> References: <20220915081451.633983-1-sughosh.ganu@linaro.org> MIME-Version: 1.0 X-BeenThere: u-boot@lists.denx.de X-Mailman-Version: 2.1.39 Precedence: list List-Id: U-Boot discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: u-boot-bounces@lists.denx.de Sender: "U-Boot" X-Virus-Scanned: clamav-milter 0.103.6 at phobos.denx.de X-Virus-Status: Clean Add documentattion for the FWU Multi Bank Update feature. The document describes the steps needed for setting up the platform for the feature, as well as steps for enabling the feature on the platform. Signed-off-by: Sughosh Ganu --- Changes since V9: None doc/develop/uefi/fwu_updates.rst | 165 +++++++++++++++++++++++++++++++ doc/develop/uefi/index.rst | 1 + doc/develop/uefi/uefi.rst | 2 + 3 files changed, 168 insertions(+) create mode 100644 doc/develop/uefi/fwu_updates.rst diff --git a/doc/develop/uefi/fwu_updates.rst b/doc/develop/uefi/fwu_updates.rst new file mode 100644 index 0000000000..fad3fbb3a8 --- /dev/null +++ b/doc/develop/uefi/fwu_updates.rst @@ -0,0 +1,165 @@ +.. SPDX-License-Identifier: GPL-2.0+ +.. Copyright (c) 2022 Linaro Limited + +FWU Multi Bank Updates in U-Boot +================================ + +The FWU Multi Bank Update feature implements the firmware update +mechanism described in the PSA Firmware Update for A-profile Arm +Architecture specification [1]. Certain aspects of the Dependable +Boot specification [2] are also implemented. The feature provides a +mechanism to have multiple banks of updatable firmware images and for +updating the firmware images on the non-booted bank. On a successful +update, the platform boots from the updated bank on subsequent +boot. The UEFI capsule-on-disk update feature is used for performing +the actual updates of the updatable firmware images. + +The bookkeeping of the updatable images is done through a structure +called metadata. Currently, the FWU metadata supports identification +of images based on image GUIDs stored on a GPT partitioned storage +media. There are plans to extend the metadata structure for non GPT +partitioned devices as well. + +Accessing the FWU metadata is done through generic API's which are +defined in a driver which complies with the U-Boot's driver model. A +new uclass UCLASS_FWU_MDATA has been added for accessing the FWU +metadata. Individual drivers can be added based on the type of storage +media, and it's partitioning method. Details of the storage device +containing the FWU metadata partitions are specified through a U-Boot +specific device tree property `fwu-mdata-store`. Please refer to +U-Boot `doc `__ +for the device tree bindings. + +Enabling the FWU Multi Bank Update feature +------------------------------------------ + +The feature can be enabled by specifying the following configs:: + + CONFIG_EFI_CAPSULE_ON_DISK=y + CONFIG_EFI_CAPSULE_FIRMWARE_MANAGEMENT=y + CONFIG_EFI_CAPSULE_FIRMWARE=y + CONFIG_EFI_CAPSULE_FIRMWARE_RAW=y + + CONFIG_FWU_MULTI_BANK_UPDATE=y + CONFIG_CMD_FWU_METADATA=y + CONFIG_DM_FWU_MDATA=y + CONFIG_FWU_MDATA_GPT_BLK=y + CONFIG_FWU_NUM_BANKS= + CONFIG_FWU_NUM_IMAGES_PER_BANK= + +in the .config file + +The first group of configuration settings enable the UEFI +capsule-on-disk update functionality. The second group of configs +enable the FWU Multi Bank Update functionality. Please refer to the +section :ref:`uefi_capsule_update_ref` for more details on generation +of the UEFI capsule. + +Setting up the device for GPT partitioned storage +------------------------------------------------- + +Before enabling the functionality in U-Boot, a GPT partitioned storage +device is required. Assuming a GPT partitioned storage device, the +storage media needs to be partitioned with the correct number of +partitions, given the number of banks and number of images per bank +that the platform is going to support. Each updatable firmware image +will be stored on an separate partition. In addition, the two copies +of the FWU metadata will be stored on two separate partitions. + +As an example, a platform supporting two banks with each bank +containing three images would need to have 2 * 3 = 6 partitions plus +the two metadata partitions, or 8 partitions. In addition the storage +media can have additional partitions of non-updatable images, like the +EFI System Partition(ESP), a partition for the root file system +etc. An example list of images on the storage medium would be + +* FWU metadata 1 +* U-Boot 1 +* OP-TEE 1 +* FWU metadata 2 +* OP-TEE 2 +* U-Boot 2 +* ESP +* rootfs + +When generating the partitions, a few aspects need to be taken care +of. Each GPT partition entry in the GPT header has two GUIDs:: + +* PartitionTypeGUID +* UniquePartitionGUID + +The PartitionTypeGUID value should correspond to the +``image_type_uuid`` field of the FWU metadata. This field is used to +identify a given type of updatable firmware image, e.g. U-Boot, +OP-TEE, FIP etc. This GUID should also be used for specifying the +`--guid` parameter when generating the capsule. + +The UniquePartitionGUID value should correspond to the ``image_uuid`` +field in the FWU metadata. This GUID is used to identify images of a +given image type in different banks. + +Similarly, the FWU specifications defines the GUID value to be used +for the metadata partitions. This would be the PartitionTypeGUID for +the metadata partitions. + +When generating the metadata, the ``image_type_uuid`` and the +``image_uuid`` values should match the *PartitionTypeGUID* and the +*UniquePartitionGUID* values respectively. + +Performing the Update +--------------------- + +Once the storage media has been partitioned and populated with the +metadata partitions, the UEFI capsule-on-disk update functionality can +be used for performing the update. Refer to the section +:ref:`uefi_capsule_update_ref` for details on how the update can be +invoked. + +On a successful update, the FWU metadata gets updated to reflect the +bank from which the platform would be booting on subsequent boot. + +Based on the value of bit15 of the Flags member of the capsule header, +the updated images would either be accepted by the U-Boot's UEFI +implementation, or by the Operating System. If the Operating System is +accepting the firmware images, it does so by generating an empty +*accept* capsule. The Operating System can also reject the updated +firmware by generating a *revert* capsule. The empty capsule can be +applied by using the exact same procedure used for performing the +capsule-on-disk update. + +The task of accepting the different firmware images, post an update +may be done by multiple, separate components in the Operating +System. To help identify the firmware image that is being accepted, +the accept capsule passes the image GUID of the firmware image being +accepted. The relevant code in U-Boot then sets the Accept bit of the +corresponding firmware image for which the accept capsule was +found. Only when all the firmware components in a bank have been +accepted does the platform transition to the regular state from trial +state. + +The revert capsule on the other hand does not pass any image GUID, +since reverting any image of the bank has the same result of the +platform booting from the other bank on subsequent boot. + +Generating an empty capsule +--------------------------- + +The empty capsule can be generated using the mkeficapsule utility. To +build the tool, enable:: + + CONFIG_TOOLS_MKEFICAPSULE=y + +Run the following commands to generate the accept/revert capsules:: + +.. code-block:: bash + + $ ./tools/mkeficapsule \ + [--fw-accept --guid ] | \ + [--fw-revert] \ + + +Links +----- + +* [1] https://developer.arm.com/documentation/den0118/a/ - FWU Specification +* [2] https://git.codelinaro.org/linaro/dependable-boot/mbfw/uploads/6f7ddfe3be24e18d4319e108a758d02e/mbfw.pdf - Dependable Boot Specification diff --git a/doc/develop/uefi/index.rst b/doc/develop/uefi/index.rst index 7e65dbc5d5..e26b1fbe05 100644 --- a/doc/develop/uefi/index.rst +++ b/doc/develop/uefi/index.rst @@ -13,3 +13,4 @@ can be run an UEFI payload. uefi.rst u-boot_on_efi.rst iscsi.rst + fwu_updates.rst diff --git a/doc/develop/uefi/uefi.rst b/doc/develop/uefi/uefi.rst index 941e427093..536b278dd9 100644 --- a/doc/develop/uefi/uefi.rst +++ b/doc/develop/uefi/uefi.rst @@ -277,6 +277,8 @@ Enable ``CONFIG_OPTEE``, ``CONFIG_CMD_OPTEE_RPMB`` and ``CONFIG_EFI_MM_COMM_TEE` [1] https://optee.readthedocs.io/en/latest/building/efi_vars/stmm.html +.. _uefi_capsule_update_ref: + Enabling UEFI Capsule Update feature ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~