From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CC1EE2BEFFD; Mon, 12 Jan 2026 21:41:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768254117; cv=none; b=cTxhK4+pYj6jptHjy4BCaWsIvmVM3EWYDR/Me9E/4u9H2g6ECnG3lo1k6b/kYmBIgMdIiUwuFohvSN+LzkoShc91tRHTWZmrWx9Vcgojd+te01MlRWP8mE7NSugLiof2urxqgLVOvyDl8voqhDPstSeRo4xv1OuuBFsgBtomOSA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768254117; c=relaxed/simple; bh=sGJCmX/HliLDAhFR8jn4f9Rtt6JLol6dbDTmt2tzDk0=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=dwMUFLU04hmUYP1BkEVkedknKKe7wPlcliUoKDFd47Zw4GaHmTygPwJpX9kmtmDICZi0hk5XK1AQcZrESlHLDIiIVrkNiVMpXN9aN402//kSY8cg3ojrqUe5Y7ft3DYYiaBP8UCAM3Xx/88cuwNKHSke0h8BFSJWwgOk/p990kk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=t6pGwNll; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="t6pGwNll" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0F3B2C116D0; Mon, 12 Jan 2026 21:41:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1768254117; bh=sGJCmX/HliLDAhFR8jn4f9Rtt6JLol6dbDTmt2tzDk0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=t6pGwNlliZ6xm7wTeAHvptowfLFeYMm1dKlTw9AKn8l5NB2hf1kNqB0W2FlbcUH8H G7nbLAZD5N+8n3gqVh55QqwyqE86qGmsPCquA9fOLtBRVlXTtIHNtxUKrvXmzRaaFW Se0h7Q0Xux08r3DC3Rm87rHCtc2bATy2X/NAkleGFRRyUGf6IOy4OMsMopLXEsS4TE Fd7mzDpRkY9sDgmkIeDRmct/nj3VTo8YpIjg6OE5vf/JMGOqTvthlebkqV7cD1a7c7 9AvziqXSsWN3w4g9JzAWbGfyxC0oLyU2wgBcRk/Ae8D8rZfjKGd+VJINDO4RSH12k1 ayWRj5yc2mwTQ== Date: Mon, 12 Jan 2026 21:41:50 +0000 From: Conor Dooley To: Guodong Xu Cc: Rob Herring , Krzysztof Kozlowski , Conor Dooley , Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexandre Ghiti , Yixun Lan , Daniel Lezcano , Thomas Gleixner , Samuel Holland , Anup Patel , Greg Kroah-Hartman , Jiri Slaby , Lubomir Rintel , Yangyu Chen , Paul Walmsley , Heinrich Schuchardt , Kevin Meng Zhang , Andrew Jones , devicetree@vger.kernel.org, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, spacemit@lists.linux.dev, linux-serial@vger.kernel.org Subject: Re: [PATCH v4 06/11] dt-bindings: riscv: Add B ISA extension description Message-ID: <20260112-veal-retaliate-7cf9a2981aaf@spud> References: <20260110-k3-basic-dt-v4-0-d492f3a30ffa@riscstar.com> <20260110-k3-basic-dt-v4-6-d492f3a30ffa@riscstar.com> Precedence: bulk X-Mailing-List: linux-serial@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="jl0lukoungssHXqm" Content-Disposition: inline In-Reply-To: <20260110-k3-basic-dt-v4-6-d492f3a30ffa@riscstar.com> --jl0lukoungssHXqm Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Sat, Jan 10, 2026 at 01:18:18PM +0800, Guodong Xu wrote: > Add description of the single-letter B extension for Bit Manipulation. > B is mandatory for RVA23U64. >=20 > The B extension is ratified in the 20240411 version of the unprivileged > ISA specification. According to the ratified spec, the B standard > extension comprises instructions provided by the Zba, Zbb, and Zbs > extensions. >=20 > Add two-way dependency check to enforce that B implies Zba/Zbb/Zbs; and > when Zba/Zbb/Zbs (all of them) are specified, then B must be added too. >=20 > The reason why B/Zba/Zbb/Zbs must coexist at the same time is that > unlike other single-letter extensions, B was ratified (Apr/2024) much > later than its component extensions Zba/Zbb/Zbs (Jun/2021). >=20 > When "b" is specified, zba/zbb/zbs must be present to ensure > backward compatibility with existing software and kernels that only > look for the explicit component strings. >=20 > When all three components zba/zbb/zbs are specified, "b" should also be > present. Making "b" mandatory when all three components are present. > Existing devicetrees with zba/zbb/zbs but without "b" will generate > warnings that can be fixed in follow-up patches. Are you going to send these fixup patches for other devicetrees? The majority appear to be other spacemit devices. --jl0lukoungssHXqm Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQRh246EGq/8RLhDjO14tDGHoIJi0gUCaWVqngAKCRB4tDGHoIJi 0qwfAQCamQ336+8Ol6Cm4BGdZ1WngDrqc6adOnM/s3WibPSj1gEA5adimCDCrVEG eLvwJuJiBsmzP57dHrSu22VBtIaN9gE= =7BIS -----END PGP SIGNATURE----- --jl0lukoungssHXqm--