From patchwork Fri Feb 13 21:17:32 2026 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Simon Glass X-Patchwork-Id: 1856 Return-Path: X-Original-To: u-boot-concept@u-boot.org Delivered-To: u-boot-concept@u-boot.org DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=u-boot.org; s=default; t=1771017477; bh=XaQGwxdK2MU1nPNI3kQ7K4Cm8GTioOuWCtyUSR8tFQg=; h=From:To:Date:In-Reply-To:References:CC:Subject:List-Id: List-Archive:List-Help:List-Owner:List-Post:List-Subscribe: List-Unsubscribe:From; b=mtQu3VYVwfLX8kmiWI2UBYw3WurWSoP+OsPivMrKcu3TgeOyHGjB7fy3xEsQzMw99 OO6HXzDusv/J2UgAojOA9RCg7dnYsK8mQScEUGGsbh9KciQPfKXw3CmLRVMJKaB8Jx M8EFfzXomTxw75b52ha1NJ3uGXfX3oQmVsyK/SZH/il0BEgmrIk4DHhZlj5in5TykV fYVg1GUzzjrPq04+j0vheWVueeVuT591+mwj+CVteAjY6iNgBN5W65CZHmi04Q/z7/ Fg/vgy0+Fq3A3gX1d4qYz+jN6ZAP6pIBfDk0/tlQgDOB7Yws+4r0kBsj8YqyHRGwgO 03FOOdSeil4dA== Received: from localhost (localhost [127.0.0.1]) by mail.u-boot.org (Postfix) with ESMTP id E0A8669B42 for ; Fri, 13 Feb 2026 14:17:57 -0700 (MST) X-Virus-Scanned: Debian amavis at Received: from mail.u-boot.org ([127.0.0.1]) by localhost (mail.u-boot.org [127.0.0.1]) (amavis, port 10024) with ESMTP id vkKscUbj1vQ6 for ; Fri, 13 Feb 2026 14:17:57 -0700 (MST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=u-boot.org; s=default; t=1771017477; bh=XaQGwxdK2MU1nPNI3kQ7K4Cm8GTioOuWCtyUSR8tFQg=; h=From:To:Date:In-Reply-To:References:CC:Subject:List-Id: List-Archive:List-Help:List-Owner:List-Post:List-Subscribe: List-Unsubscribe:From; b=mtQu3VYVwfLX8kmiWI2UBYw3WurWSoP+OsPivMrKcu3TgeOyHGjB7fy3xEsQzMw99 OO6HXzDusv/J2UgAojOA9RCg7dnYsK8mQScEUGGsbh9KciQPfKXw3CmLRVMJKaB8Jx M8EFfzXomTxw75b52ha1NJ3uGXfX3oQmVsyK/SZH/il0BEgmrIk4DHhZlj5in5TykV fYVg1GUzzjrPq04+j0vheWVueeVuT591+mwj+CVteAjY6iNgBN5W65CZHmi04Q/z7/ Fg/vgy0+Fq3A3gX1d4qYz+jN6ZAP6pIBfDk0/tlQgDOB7Yws+4r0kBsj8YqyHRGwgO 03FOOdSeil4dA== Received: from mail.u-boot.org (localhost [127.0.0.1]) by mail.u-boot.org (Postfix) with ESMTP id CFF4269B3E for ; Fri, 13 Feb 2026 14:17:57 -0700 (MST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=u-boot.org; s=default; t=1771017476; bh=qZc7ePSwSZ3gjqaEGfvOf7D2umT1AYovEBuOT0dxOow=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=eRJQ3z+YmaN2B1+FFYPCr3JMPWdSWHZ4Z+aMQZ9NmQ4xwWEBGM7KfsOEb0uNSf8oY M2/N7pBPppkXBxMoJobyF/ekeaUOYVxfuZuC4ape6VKhTMOsjV4B0OQAv05JwN5QSn 40fx6bhDViRcE1HBUsGpGfZHub4wyXrWQivipfIUGL+jgzt4HRmTlsLSfDGuuEufxS AW0zRnW5mnhNK3qrdiaeymdMeF5faz21B6AiqAZVwlswT1KsAtU7nD7H6So4Z74G8i o/1NGBe3Za1jdJg+BEIMpE2wVWhtl7RyzkdKm+uKx+xdMZbS93C1BvhJu7TWbWzjoN YhcYHErFUrw/w== Received: from localhost (localhost [127.0.0.1]) by mail.u-boot.org (Postfix) with ESMTP id 754CF69B3D; Fri, 13 Feb 2026 14:17:56 -0700 (MST) X-Virus-Scanned: Debian amavis at Received: from mail.u-boot.org ([127.0.0.1]) by localhost (mail.u-boot.org [127.0.0.1]) (amavis, port 10026) with ESMTP id Td3X3TVD47tv; Fri, 13 Feb 2026 14:17:56 -0700 (MST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=u-boot.org; s=default; t=1771017472; bh=4pRb6M449iL7KztWO1ZtFOXYMiiat7HDYSiC2e7C8Yw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=sI5ZNpoeXfiJsii1MZMI+JFE/mfGoF20FYqElfgnBXMUKVr25Uv7UGv/bVowiyDbs wKkq1QCzf+BsTSDFdO9rbRZUjYlloLstahHpE7fb9oB8UK1M4JN/l73jGQyuCQDrAU Nt6LOOw0LBhjFaRdySM6zYwgJzmHMsiS0QuOjXpXoFhmwrUx3woYU74D7r5V30Mk2m duWbMJqI5axK6I+hVqIC1ajGq6fg1+q8R3B5tGHajHyZH/Hndlc4Uvqp7WxuOjHfBv a+3fjeXv30fOcZQ5HSyE6HOwvQtfk6r3/K1NI7AmpFWXeWvC+e7rdad/ynH171NBPd +OCU0yEvP8Sjw== Received: from u-boot.org (unknown [73.34.74.121]) by mail.u-boot.org (Postfix) with ESMTPSA id 1ECC569B31; Fri, 13 Feb 2026 14:17:52 -0700 (MST) From: Simon Glass To: U-Boot Concept Date: Fri, 13 Feb 2026 14:17:32 -0700 Message-ID: <20260213211739.381127-2-sjg@u-boot.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260213211739.381127-1-sjg@u-boot.org> References: <20260213211739.381127-1-sjg@u-boot.org> MIME-Version: 1.0 Message-ID-Hash: 27JPO7O3IUHBQOZGH4EGRLQYNOTNMGNP X-Message-ID-Hash: 27JPO7O3IUHBQOZGH4EGRLQYNOTNMGNP X-MailFrom: sjg@u-boot.org X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; loop; banned-address; emergency; member-moderation; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header CC: Simon Glass , "Claude Opus 4 . 6" X-Mailman-Version: 3.3.10 Precedence: list Subject: [Concept] [PATCH 1/5] doc: bls: Fix Sphinx cross-references and improve text List-Id: Discussion and patches related to U-Boot Concept Archived-At: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: From: Simon Glass Use proper references in the "See Also" section and tighten some of the prose. Co-developed-by: Claude Opus 4.6 Signed-off-by: Simon Glass --- doc/usage/bls.rst | 33 ++++++++++++++++++--------------- 1 file changed, 18 insertions(+), 15 deletions(-) diff --git a/doc/usage/bls.rst b/doc/usage/bls.rst index f96652bd242..128092ae25b 100644 --- a/doc/usage/bls.rst +++ b/doc/usage/bls.rst @@ -1,7 +1,7 @@ .. SPDX-License-Identifier: GPL-2.0+ -Boot Loader Specification (BLS) Type #1 Support -================================================ +Boot Loader Specification (BLS) +=============================== U-Boot supports Boot Loader Specification (BLS) Type #1 boot entries as defined in the `Boot Loader Specification`_. @@ -26,7 +26,7 @@ Enable BLS support with:: CONFIG_BOOTMETH_BLS=y -This automatically selects ``CONFIG_PXE_UTILS`` for boot execution. +This automatically selects ``CONFIG_PXE_UTILS`` for booting. BLS Entry Format ---------------- @@ -75,6 +75,11 @@ are not currently supported by U-Boot: * ``uki-url`` - Remote UKI reference * ``profile`` - Multi-profile UKI selector +Fields that support multiple occurrences: + +* ``options`` - All values are concatenated with spaces +* ``initrd`` - All paths are loaded consecutively in memory + .. _Unified Kernel Images: https://uapi-group.org/specifications/specs/unified_kernel_image/ U-Boot Extensions @@ -109,26 +114,22 @@ FITs can be specified in two ways: fit /boot/image.fit The PXE boot infrastructure handles FIT parsing automatically in both cases. - -Multiple Values ---------------- - -Fields that support multiple occurrences: - -* ``options`` - All values are concatenated with spaces -* ``initrd`` - All paths are loaded consecutively in memory +The second option is preferred since the standard 'best match' algorithm +(enabled by ``CONFIG_FIT_BEST_MATCH=y``) should normally used to select the +correct configuration. Usage ----- -BLS boot entries are discovered automatically during standard boot:: +BLS boot entries are discovered automatically by standard boot:: => bootflow scan => bootflow list => bootflow select 0 => bootflow boot -The BLS entry at ``loader/entry.conf`` is discovered as a bootflow. +The BLS entry at ``loader/entry.conf`` on any available media is recognised as +a bootflow. Implementation Notes -------------------- @@ -154,5 +155,7 @@ Current Limitations See Also -------- -* doc/develop/bootstd.rst - Standard boot framework -* doc/usage/cmd/bootflow.rst - Bootflow command reference +* :doc:`/develop/bootstd/index` +* :doc:`/usage/cmd/bootflow` +* `Boot Loader Specification `_ +* `Unified Kernel Image `_