From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=150.107.74.76 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794370779; b=1050wd9k3KU+RxJJL2wyVjFLPMgByCpU36aiPcauZKfNMCRkYNtkKVGOfqpLioopbza9 4xJ8FSFChzHXHSNLzcdQ7efp9T1veu1sjBeBFbTxKo++CqfAwO/1bfYs4gdCOqyJaa4kH rrO9XIzqArFiC1XjNzsDee/xDNiualFHZNA1PPpNYuAQWsEuzdGnWYYl09AHPDITW2SYD +h64Oq3UDhYO36Hj7hSLo0Qe9nq9rAe84YGC0yPRm7ZOJigEzr1PAnPm0Crss/4Xhm/hE 1OotcdKf789pks73DGWHtBzaGGnBqa4mT0Lnd3sFyNCWm0oKVbCEL4myv6WVRqHGEPg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794370779; h=DMARC-Filter:DKIM-Signature:Received:Date:From:To:Cc:Subject: Message-ID:References:MIME-Version:Content-Type:Content-Disposition: In-Reply-To; bh=TI3IHO/M82WXfjUeKiU5Lf475TIvg36C3rBRJtlPeZw=; b=SJD3kZFT2zjWnEwfTtimodiMh7+0n6LplCkZKRZo4tk8MPiVtmt8iW3IhnfMRlVFuAAj RgD/AT9ChsD47NU7v2UXcLDtId2E9YE7OkwYxwGHcMvseKGhe27V1zcZZEP3xPLDpOcEO 6MJBbT/uNr9tdP1n3WbTHthN7xHrWJyZFav67Q+VPo1yBTlOYj8PuWDgb/yKcSfNI8dnQ +00FyvRPIHg/wstHIjdffCSLe+C7SIW63ia5eLEFM2tX9lNZ2FvrdtSR1/T4E6OTu0ADe atYtuvlwkW0MfUUvn7/i4TJmioy+FD614Kv9HQHQMQ3QAFCSH5nH0tIqy0hfg7053rg== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none header.from=gibson.dropbear.id.au; spf=pass smtp.mailfrom=gandalf.ozlabs.org; dkim=pass header.d=gibson.dropbear.id.au header.i=@gibson.dropbear.id.au header.a=rsa-sha256 header.s=202610 header.b=TaQq4trl; arc=none smtp.remote-ip=150.107.74.76 Received: from mail.ozlabs.org (gandalf.ozlabs.org [150.107.74.76]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3536B606A33D; Wed, 11 Nov 2026 04:19:38 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 3536B606A33D Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=gibson.dropbear.id.au Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gandalf.ozlabs.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gibson.dropbear.id.au header.i=@gibson.dropbear.id.au header.a=rsa-sha256 header.s=202610 header.b=TaQq4trl DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gibson.dropbear.id.au; s=202610; t=1794370776; bh=TI3IHO/M82WXfjUeKiU5Lf475TIvg36C3rBRJtlPeZw=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=TaQq4trlxHlwcpE0HwirUy1QLR/3aJ+Zk4OvUVgHIFdEbh+gIyqy5fOqLfYIcAOit 2e2mS0942BLKnlAGYDvABipkRXABN1eyQNZSPe4mUr8+vTu5kFpv45MTi09jjledgA u9yW8DY3auNGUWG95uZbQnFUVBEx8/OpJZlCljKCsRNEQF9Mf/xIWh3pzn20L6qsvj wD8Z+AT30AKzd3X46e2882pEB0Ehz5MBgs6Jz+vCa3orH95xhaVNS6L8NzJ8sg9edn b92tg3LQ497ei06j4JZbrlHoDs/S1R2/yBas/GCsiTA9gglSaX9nYmgunJlAA/axoE p/rX20hzFYS1Q== Received: by gandalf.ozlabs.org (Postfix, from userid 1007) id 4jPVfJ57TFz4wDm; Wed, 11 Nov 2026 15:19:36 +1100 (AEDT) Date: Wed, 11 Nov 2026 15:19:31 +1100 From: David Gibson To: Douglas Anderson Cc: Devicetree-compiler@vger.kernel.org, Rob Herring , Krzysztof Kozlowski , Conor Dooley , Konrad Dybcio , Peter Griffin , Saravana Kannan , Devicetree@vger.kernel.org, Simon Glass , Chen-Yu Tsai , Julius Werner , Brian Norris , linux-kernel@vger.kernel.org, Tudor Ambarus , =?iso-8859-1?Q?Andr=E9?= Draszik Subject: Re: [PATCH v3 13/15] fdtfactor: Add -S/--strip-local-fixups option Message-ID: References: <20261101220224.1436242-1-dianders@chromium.org> <20261101220224.1436242-14-dianders@chromium.org> X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="bjB6qsUtsKUtE8xm" Content-Disposition: inline In-Reply-To: <20261101220224.1436242-14-dianders@chromium.org> --bjB6qsUtsKUtE8xm Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Sun, Nov 01, 2026 at 02:01:20PM -0800, Douglas Anderson wrote: > By default, `fdtfactor` preserves `/__local_fixups__` on `base.dtb` so > that when `fdt_overlay_apply()` merges a `.dtbo` overlay, the > reconstructed device tree retains full `/__local_fixups__` information > (for instance, if an OS kernel wants to know which property cells > contain phandles at runtime). >=20 > When `-L` was passed to `dtc` solely to help `fdtfactor` locate phandle > cells at build time and `/__local_fixups__` is not needed at runtime, > retaining `/__local_fixups__` in `base.dtb` wastes space. >=20 > Add `-S` / `--strip-local-fixups` to omit `/__local_fixups__` from > `base.dtb` (and therefore from the merged device trees produced by > `fdt_overlay_apply()`). On a set of 47 Qualcomm SC7180 Trogdor > Chromebook board DTBs, `fdtfactor` without `-S` reduces total > uncompressed size from 7.69 MB to 932 KB (88.2% savings), while > `fdtfactor -S` reduces it to 634 KB (91.8% savings, saving an additional > 298 KB by omitting `/__local_fixups__` from `base.dtb`). >=20 > Add a test case in `tests/run_tests.sh` verifying that `fdtfactor -S` > followed by `fdtoverlay` reproduces DTBs compiled with `-@` (without > `-L`) via `dtbs_equal_unordered`. >=20 > Assisted-by: Gemini:gemini-pro-prerelease > Signed-off-by: Douglas Anderson Reviewed-by: David Gibson --=20 David Gibson (he or they) | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you, not the other way | around. http://www.ozlabs.org/~dgibson --bjB6qsUtsKUtE8xm Content-Type: application/pgp-signature; name=signature.asc -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEO+dNsU4E3yXUXRK2zQJF27ox2GcFAmrz7NIACgkQzQJF27ox 2GeLJg/9HjuW3mPLbSJVTTcdqzKBheLAsRo7LeqpzCMUmLJcVtcKEwyvddC7UBzf WH2B0GMIaRrMEYukFr8RiAH/j9gnvHoIxi3ExGuyPdaGVbRZjL9BSIf23j7Hg5sj rsJuWWJRTYCA05Uz4FO/WVJE7vNn71mtyRuj8i+QOV9dAWiFJLFNW4BG694Ics27 9yqZJ+F3vatecyKPByKZTDUEbFMcJREdHhLIoIgXIzIUYJ2yYSpF5+obYGVlXI+X aVZ8KZkxnhJJlyconP6+8ZTR9jR9yZnOvCQLCd1YOSTZuQlN0kEGuIPYNrssIXHv vtQTnBK2NcYaNNU7g14S4QtJJCFdZmuAhxokYG+A3/VtLy9AYXhZ9yVkVLFXbC/j gmA1GfbvW0m/Iy5XXXDeOEoaDWru+1/r9OOyuuXGPXaPpyGNAL++70pcWygkk+va vaFCPicEoF0ZRqHlztAJcn7TbgdSaoCaaex3wx3taNTH83kUiYz06J5fUlHYw0O1 PtW7K65ihZfjPZ6icQ/yjSqWhUlM5mnrdXg9x7rVzpVXqaDuNYxd43jjitMK/l10 aSDYyKc8xXXhkc5fGQlORrOju4IT3Dy0kdJWYKtOcfywIo2/bt5QGyZ4u3GZcoWp AEDraAg47eSnO8c4Lx9KsOEp/NIk0yq2eBUsmmy6suw088rpvRw= =7pDU -----END PGP SIGNATURE----- --bjB6qsUtsKUtE8xm--