From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id C6D06C7EE22 for ; Thu, 11 May 2023 21:47:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:Content-Type: List-Subscribe:List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id: In-Reply-To:MIME-Version:References:Message-ID:Subject:Cc:To:From:Date: Reply-To:Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date :Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=8sb6oY+gBoBidnaQ7+e5+POPLkEiNaIc0FnNQjKmuuI=; b=A8aa6iQ/DP8be1OSVAtCR1/xtE Z1N1c40Y4Mdjn+cmecB7i9yDCPI9JEZFeW0OG59n3qIXG30OglD162TrZbGzByDyxUWsoJIYdFXr8 PFBMZVTtAdwVl3SO6SESG+vQzFLy3Ft9ro3k+CrFieQh3e3cBNMevU27Pbhla3DOcyblDyeodizZi fo2OMIj0PWSoNQc629m+NKBHToYSwLH0UbqnShkFDau5nOE9v/jOS1HM699dgP0grXRRdVszrQMoQ FMs/tCiVhdgOKkZjipr5CWk5hnGhLrXtR8prW0DRW+NSsInEHhbo5omDwzn4AQOanfOJJfAnkIoFh Sy2GqxvA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1pxE8a-00A5Iy-0c; Thu, 11 May 2023 21:47:48 +0000 Received: from dfw.source.kernel.org ([2604:1380:4641:c500::1]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1pxE8W-00A5Hw-1q for linux-riscv@lists.infradead.org; Thu, 11 May 2023 21:47:46 +0000 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id E22536135C; Thu, 11 May 2023 21:47:43 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id DF5E4C433D2; Thu, 11 May 2023 21:47:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1683841663; bh=N6lJFJqzV7ytXV6+rKvzLTpx6yPBkX401wQ/wXQJiW4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Wl4jlKhfsue4/c+zHUnLXabF7cR1b91X+0Z0SohLoB3xQfCNIeKpkTEOtl58tmT95 XIkYw3V6b9NROUr+rjpt7DpTXeftAsRn6BXaKbVCcmaehEZQ7wO8E6bg/a029tcowQ ey72wKPZEURG+TG+Bek/PzhY95qLydEe0IMV+wfQFl5MREW0QwxfgjLY5dTia0zvUq PT+HOLs0/U/1tt+5HbqigcHs1eBKPKs8RbOPEwi1U1fEDKJUTNNdJU/dmRgV3dv10Z 0ShNuEBMu+Ch/Mzy6wcYT89wFiyS3xf0PhQCuS7YXemz/SnOJdJ0tui/ENxsLKrL4L Ac774mfOgQwAQ== Date: Thu, 11 May 2023 22:47:38 +0100 From: Conor Dooley To: Atish Patra Cc: linux-riscv@lists.infradead.org, devicetree@vger.kernel.org, Conor Dooley , Heiko Stuebner , Yangyu Chen , Conor Dooley , Rob Herring , Palmer Dabbelt , Krzysztof Kozlowski , Paul Walmsley , Andrew Jones Subject: Re: [RFC 0/6] Deprecate riscv,isa DT property? Message-ID: <20230511-punctuate-dinghy-0dd9be94270c@spud> References: <20230508-hypnotic-phobia-99598439d828@spud> MIME-Version: 1.0 In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230511_144744_719529_62F9B21B X-CRM114-Status: GOOD ( 24.43 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============8020048484248184728==" Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org --===============8020048484248184728== Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="KNnUOQ8SfmCZhf4A" Content-Disposition: inline --KNnUOQ8SfmCZhf4A Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, May 11, 2023 at 02:27:44PM -0700, Atish Patra wrote: > > The other thought I had was that perhaps some software may choose not to > > implement version x.y.0 of an extension and only support x.z.0, z > y > > for some reason. We'd want to refuse that extension if the extension is > > found, but the version is not listed as being something compatible with > > x.z.0, and while the ISA spec does say that the default assumption is > > 2p0 for unversioned extensions in its current form, I struggle to > > extrapolate that to extensions not currently part of the unpriv spec, > > but rather defined on their own. > > >=20 > That's a fair point. However, any new RVI ISA extension will only have v1= =2E0 > as per my knowledge. Any new feature will have to be part of a > different extension. > At least that was the plan discussed last year. That's more than last year at this point, and nothing has changed in the documentation! Talk's cheap, ehh? > https://github.com/riscv/riscv-isa-manual/issues/781#issuecomment-9832226= 55 >=20 > Are you aware of any discussion that changes this ? It's called "trust issues". I am far less worried about the addition of new features though than the removal of existing ones. Part of me fears for fence.i-less systems for example, but there would be other ways to bodge around the mess if it comes to pass. If we are *sure* that no extensions will modify features additively or subtractively, then this may not be needed at all & I can avoid having to bend dt-validate to my will. We have no guarantees for vendor extensions on that front either, they're free to do what they like w.r.t. versioning, no? --KNnUOQ8SfmCZhf4A Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQRh246EGq/8RLhDjO14tDGHoIJi0gUCZF1iegAKCRB4tDGHoIJi 0kU0AQDe4wPkJbvFunY7Hd7tVeEqB9Nx4RBMWPuYxZW9CGVh0wEA201Uii1iRlaK nSvwRBXu5EKO8fs96wDjwGzDo9UlRAQ= =BbjJ -----END PGP SIGNATURE----- --KNnUOQ8SfmCZhf4A-- --===============8020048484248184728== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv --===============8020048484248184728==--