[{"id":3683642,"web_url":"http://patchwork.ozlabs.org/comment/3683642/","msgid":"","list_archive_url":null,"date":"2026-04-28T18:22:51","subject":"Re: [PATCH v2 4/4] doc: fastboot: Document block device selection\n syntax","submitter":{"id":6170,"url":"http://patchwork.ozlabs.org/api/people/6170/","name":"Simon Glass","email":"sjg@chromium.org"},"content":"Hi Balaji,\n\nOn 2026-04-27T12:06:41, Balaji Selvanathan\n wrote:\n> doc: fastboot: Document block device selection syntax\n>\n> Add documentation for the device selection syntax in fastboot\n> block device operations. Users can now specify target devices\n> using 'N:partition' format where N is the device number.\n>\n> Document usage examples for regular partition operations like\n> \"fastboot flash 0:boot boot.img\" and partition table operations\n> like \"fastboot flash 1:gpt gpt.img\". When no device number is\n> specified, the default from CONFIG_FASTBOOT_FLASH_BLOCK_DEVICE_ID\n> is used.\n>\n> Reviewed-by: Mattijs Korpershoek \n> Signed-off-by: Balaji Selvanathan \n>\n> doc/android/fastboot.rst | 41 +++++++++++++++++++++++++++++++++++++++++\n> 1 file changed, 41 insertions(+)\n\n> diff --git a/doc/android/fastboot.rst b/doc/android/fastboot.rst\n> @@ -147,6 +147,38 @@ The Fastboot implementation in U-Boot allows to write images into disk\n> partitions. Target partitions are referred on the host computer by\n> their names.\n>\n> +Device Selection for Block Devices\n> +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n\nOther subsection headings in this file use sentence case ('USB\nconfiguration', 'Partition aliases', etc). Please rename to 'Device\nselection for block devices' to match - and likewise 'Partition name\nformats' below.\n\n> diff --git a/doc/android/fastboot.rst b/doc/android/fastboot.rst\n> @@ -186,6 +218,15 @@ configuration options:\n> CONFIG_FASTBOOT_GPT_NAME\n> CONFIG_FASTBOOT_MBR_NAME\n>\n> +When using block devices (`FASTBOOT_FLASH_BLOCK), you can specify the target\n> +device by prefixing with the device number::\n> +\n> + fastboot flash 0:gpt gpt.img # Write GPT to device 0\n> + fastboot flash 1:mbr mbr.img # Write MBR to device 1\n> +\n> +If no device number is specified, the default device from\n> +CONFIG_FASTBOOT_FLASH_BLOCK_DEVICE_ID is used.\n\nThis duplicates what was added a few paragraphs up in 'Device\nSelection for Block Devices' (same '0:gpt'/'1:mbr' examples and the\nsame default-device sentence). How about dropping this block and\nadding a one-liner cross-reference, e.g. 'See above for the\nN:partition syntax when using FASTBOOT_FLASH_BLOCK'.\n\n> diff --git a/doc/android/fastboot.rst b/doc/android/fastboot.rst\n> @@ -147,6 +147,38 @@ The Fastboot implementation in U-Boot allows to write images into disk\n> +This syntax is supported for:\n> +\n> +* Regular partition flashing\n> +* GPT partition table updates (gpt or N:gpt)\n> +* MBR partition table updates (mbr or N:mbr`)\n> +* Partition erasing operations\n\nJust to check, does erase actually go through the same parser? It does\ntoday via fastboot_block_get_part_info(), but worth confirming it's\nexercised since the commit message only mentions flash.\n\nRegards,\nSimon","headers":{"Return-Path":"","X-Original-To":"incoming@patchwork.ozlabs.org","Delivered-To":"patchwork-incoming@legolas.ozlabs.org","Authentication-Results":["legolas.ozlabs.org;\n\tdkim=pass (1024-bit key;\n unprotected) header.d=chromium.org header.i=@chromium.org header.a=rsa-sha256\n header.s=google header.b=TiXFJJNF;\n\tdkim-atps=neutral","legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=lists.denx.de\n (client-ip=2a01:238:438b:c500:173d:9f52:ddab:ee01; helo=phobos.denx.de;\n envelope-from=u-boot-bounces@lists.denx.de; receiver=patchwork.ozlabs.org)","phobos.denx.de;\n dmarc=pass (p=none dis=none) header.from=chromium.org","phobos.denx.de;\n spf=pass smtp.mailfrom=u-boot-bounces@lists.denx.de","phobos.denx.de;\n\tdkim=pass (1024-bit key;\n unprotected) header.d=chromium.org header.i=@chromium.org\n header.b=\"TiXFJJNF\";\n\tdkim-atps=neutral","phobos.denx.de;\n dmarc=pass (p=none dis=none) header.from=chromium.org","phobos.denx.de;\n spf=pass smtp.mailfrom=sjg@chromium.org"],"Received":["from phobos.denx.de (phobos.denx.de\n [IPv6:2a01:238:438b:c500:173d:9f52:ddab:ee01])\n\t(using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)\n\t key-exchange x25519)\n\t(No client certificate requested)\n\tby legolas.ozlabs.org (Postfix) with ESMTPS id 4g4phc20W4z1xrS\n\tfor ; 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Tue, 28 Apr 2026\n 11:23:03 -0700 (PDT)","MIME-Version":"1.0","References":"<20260427-fb_gpt-v2-0-9e7fe3c1649a@oss.qualcomm.com>\n <20260427-fb_gpt-v2-4-9e7fe3c1649a@oss.qualcomm.com>","In-Reply-To":"<20260427-fb_gpt-v2-4-9e7fe3c1649a@oss.qualcomm.com>","From":"Simon Glass ","Date":"Tue, 28 Apr 2026 12:22:51 -0600","X-Gm-Features":"AVHnY4IT6N-nU8qI0AvUbi2Wmd0JXr_owuMA22rVxHizqAHPA_89NtKGsk5fvok","Message-ID":"\n ","Subject":"Re: [PATCH v2 4/4] doc: fastboot: Document block device selection\n syntax","To":"balaji.selvanathan@oss.qualcomm.com","Cc":"u-boot@lists.denx.de, Mattijs Korpershoek ,\n Tom Rini , Heiko Schocher ,\n Neil Armstrong ,\n Dmitrii Merkurev ,\n Adrian Freihofer , Peng Fan ,\n Jaehoon Chung ,\n \"Ariel D'Alessandro\" ","Content-Type":"text/plain; charset=\"UTF-8\"","X-BeenThere":"u-boot@lists.denx.de","X-Mailman-Version":"2.1.39","Precedence":"list","List-Id":"U-Boot discussion ","List-Unsubscribe":",\n ","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n ","Errors-To":"u-boot-bounces@lists.denx.de","Sender":"\"U-Boot\" ","X-Virus-Scanned":"clamav-milter 0.103.8 at phobos.denx.de","X-Virus-Status":"Clean"}}]