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 EA5B3C10F1A for ; Thu, 9 May 2024 08:17:53 +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=QMD7aLwdrazkQzHic3x+3Hg7VDKS5WpD0jviHmGcEAI=; b=wJL8224i3iU4yx3qAjvvPbm+ID pX2zh/FQWzOEhvyK0uWdt8UmfDvuBe5C/VwXCKj/UVkbu3yiTo9vNfCx1uDrsYPB0LNTKmc+2upNn 2st7VJ8uYLxsFMG/XHPRmihoW67JnZWvpaoy1eit2xCpelQCWeNQ8KpSSXAzaoYa72fHvyjmEvywH 0a/364DSXwI0WCTac5UOohJfSvWwfGGwRmiTv82cZY/50y2RorSoA5Rixf6fSWW+Vozhur11SykAq yxVvmjhW2ir8C/IxhhLmRAX8FbUmzq22DpYJ1ay9LEF6TF5ZpVkga0wA3eXY5yapi5AGxi41wQHX2 s0YToQvQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1s4yyD-00000000nxb-14Wz; Thu, 09 May 2024 08:17:41 +0000 Received: from esa.microchip.iphmx.com ([68.232.153.233]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1s4yy9-00000000nvx-26e1; Thu, 09 May 2024 08:17:39 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=microchip.com; i=@microchip.com; q=dns/txt; s=mchp; t=1715242657; x=1746778657; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=lMaYXea0/pL6iEr0T3fEYaeD0BO/p+aXtvy3hTqRvxI=; b=kaV5bMScuN56QtRE7MSggUQJwSqmtoQ+TOchzWeg1PjkcQb3lIYoArfM ZSwmx8KBRT/tmNGCrOBuXsdk2klhLytOPbHuUqqkVM3wUSZWm7Lqvhra5 Hg1u+5glRsUW6TRur0VKKe+u0WJT0L/nfKH4j1e4omW3rjoTMiEEoAhgo t60g/9PUemwPfgKA60FPdcwAGD6zFlgHgfhnbglEDMVopcWodSKIXrPBA LHt6NaC7BIdARAaIe3mOP1IuiLh7W52mZT6XGQ7ejB0na6jy1CKM7da47 KxbD7bpcWbOMpbC/cnsornoVs0wRZBro5ncutuFDCUz3Wv0bnjNH79QFN w==; X-CSE-ConnectionGUID: 0mKwrjsVTF+mfP6kb6VBzw== X-CSE-MsgGUID: w51U2VCEQquHoJanXOK8gQ== X-IronPort-AV: E=Sophos;i="6.08,147,1712646000"; d="asc'?scan'208";a="26482894" X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN Received: from unknown (HELO email.microchip.com) ([170.129.1.10]) by esa1.microchip.iphmx.com with ESMTP/TLS/ECDHE-RSA-AES128-GCM-SHA256; 09 May 2024 01:17:34 -0700 Received: from chn-vm-ex04.mchp-main.com (10.10.85.152) by chn-vm-ex04.mchp-main.com (10.10.85.152) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.35; Thu, 9 May 2024 01:17:24 -0700 Received: from wendy (10.10.85.11) by chn-vm-ex04.mchp-main.com (10.10.85.152) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.35 via Frontend Transport; Thu, 9 May 2024 01:17:20 -0700 Date: Thu, 9 May 2024 09:17:09 +0100 From: Conor Dooley To: Charlie Jenkins CC: Conor Dooley , Rob Herring , Krzysztof Kozlowski , Paul Walmsley , Palmer Dabbelt , Albert Ou , Guo Ren , Conor Dooley , Chen-Yu Tsai , Jernej Skrabec , Samuel Holland , Evan Green , =?iso-8859-1?Q?Cl=E9ment_L=E9ger?= , Jonathan Corbet , Shuah Khan , , , , Palmer Dabbelt , , , , Subject: Re: [PATCH v6 03/17] riscv: vector: Use vlenb from DT Message-ID: <20240509-quickly-nibble-01cdb4e541ee@wendy> References: <20240503-dev-charlie-support_thead_vector_6_9-v6-0-cb7624e65d82@rivosinc.com> <20240503-dev-charlie-support_thead_vector_6_9-v6-3-cb7624e65d82@rivosinc.com> MIME-Version: 1.0 In-Reply-To: <20240503-dev-charlie-support_thead_vector_6_9-v6-3-cb7624e65d82@rivosinc.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240509_011737_575553_B1EC0419 X-CRM114-Status: GOOD ( 16.77 ) X-BeenThere: linux-arm-kernel@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="===============3846715816217366425==" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org --===============3846715816217366425== Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="ftL9clxrsKa3hb4u" Content-Disposition: inline --ftL9clxrsKa3hb4u Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Hey Charlie, Just me being a pain again... On Fri, May 03, 2024 at 11:18:18AM -0700, Charlie Jenkins wrote: > @@ -671,6 +713,11 @@ void __init riscv_fill_hwcap(void) > pr_info("Falling back to deprecated \"riscv,isa\"\n"); > riscv_fill_hwcap_from_isa_string(isa2hwcap); > } > + > + if (elf_hwcap & COMPAT_HWCAP_ISA_V && has_riscv_homogeneous_vlenb() < 0) { > + pr_warn("Unsupported heterogeneous vlen detected, vector extension disabled.\n"); > + elf_hwcap &= ~COMPAT_HWCAP_ISA_V; > + } > } After replying to Andy this morning about doing some dependency checking for vector-reliant extensions I realised that we're actually doing this check too late to be useful for that case. Say for Zvkb we want to check if vector has been enabled before marking the extension available, and without Clement's series that re-works the riscv_isa_extension_check(), we need to ensure that vector support isn't gonna get turned after we've already marked Zvkb as usable. If we could move the riscv_has_homogeneous_vlenb() call before probing extensions we could then examine the result in riscv_isa_extension_check() for V and make sure it doesn't get enabled in the first place, rather than clearing it after the fact. There's a whole load of moving pieces between different series here at the moment though, I wish some of it would land so that I could send some cleanup patches for what I think is inconsistency on top :) I wouldn't mind if this landed as-is, it's still an improvement and the user I mention above doesn't actually exist yet. Reviewed-by: Conor Dooley Cheers, Conor. --ftL9clxrsKa3hb4u Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQRh246EGq/8RLhDjO14tDGHoIJi0gUCZjyGhQAKCRB4tDGHoIJi 0u56AP95eBVgYwPh58UnZa0lZuyLzeDG6PlD0hXLsOA0eWnxUwEAqvt6X42WuHh8 3JcdzsXkKeCVaTmE3NYKMOyV9FDU3Q4= =JxGW -----END PGP SIGNATURE----- --ftL9clxrsKa3hb4u-- --===============3846715816217366425== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel --===============3846715816217366425==--