From nobody Mon Feb 9 06:50:59 2026 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 36E87C001DF for ; Wed, 26 Jul 2023 17:46:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232041AbjGZRq4 (ORCPT ); Wed, 26 Jul 2023 13:46:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41948 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232066AbjGZRqs (ORCPT ); Wed, 26 Jul 2023 13:46:48 -0400 Received: from cstnet.cn (smtp81.cstnet.cn [159.226.251.81]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DFE5F2D7B; Wed, 26 Jul 2023 10:46:40 -0700 (PDT) Received: from xmz-huawei.. (unknown [114.249.159.178]) by APP-03 (Coremail) with SMTP id rQCowABXd2TfW8Fkh6U1Dg--.53842S2; Thu, 27 Jul 2023 01:46:07 +0800 (CST) From: Mingzheng Xing To: Paul Walmsley , Palmer Dabbelt , Albert Ou , Nathan Chancellor , Nick Desaulniers , Tom Rix Cc: Bin Meng , linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, llvm@lists.linux.dev, stable@vger.kernel.org, Mingzheng Xing Subject: [PATCH v2] riscv: Handle zicsr/zifencei issue between gcc and binutils Date: Thu, 27 Jul 2023 01:45:24 +0800 Message-Id: <20230726174524.340952-1-xingmingzheng@iscas.ac.cn> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: rQCowABXd2TfW8Fkh6U1Dg--.53842S2 X-Coremail-Antispam: 1UD129KBjvJXoWxXw1kGry5ZFWrCrWUKryrCrg_yoWrJFWfpr ZxCryUGrs5X3ykGr1fJw4UW34Yyws5J3y8WrW7Kw15u3sxAFy0gr9Yyw42qFyUAFZ7Kw4q 9w1S93ZYq3Z0yaDanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUkE14x267AKxVW8JVW5JwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2ocxC64kIII0Yj41l84x0c7CEw4AK67xGY2AK02 1l84ACjcxK6xIIjxv20xvE14v26r1j6r1xM28EF7xvwVC0I7IYx2IY6xkF7I0E14v26r4j 6F4UM28EF7xvwVC2z280aVAFwI0_Jr0_Gr1l84ACjcxK6I8E87Iv6xkF7I0E14v26r4j6r 4UJwAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0 I7IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r1j6r 4UM4x0Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwACI402YVCY1x02628v n2kIc2xKxwCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F4 0E14v26r1j6r18MI8I3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_Jw0_GFyl IxkGc2Ij64vIr41lIxAIcVC0I7IYx2IY67AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxV AFwI0_Gr0_Cr1lIxAIcVCF04k26cxKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r1j 6r4UMIIF0xvEx4A2jsIEc7CjxVAFwI0_Gr0_Gr1UYxBIdaVFxhVjvjDU0xZFpf9x0JUdHU DUUUUU= X-Originating-IP: [114.249.159.178] X-CM-SenderInfo: 50lqwzhlqj6xxhqjqxpvfd2hldfou0/1tbiCQgECmTBJKN66QAAs+ Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Binutils-2.38 and GCC-12.1.0 bump[0] default ISA spec to newer version 20191213 which moves some instructions from the I extension to the Zicsr and Zifencei extensions. So if one of the binutils and GCC exceeds that version, we should turn on TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI to cope with the new changes. The case of clang is special[1][2], where older clang versions (<17) need to be rolled back to old ISA spec to fix it. And the less common case, since older GCC versions (<11.1.0) did not support zicsr and zifencei extension for -march, also requires a fallback to cope with it. For more information, please refer to: commit 6df2a016c0c8 ("riscv: fix build with binutils 2.38") commit e89c2e815e76 ("riscv: Handle zicsr/zifencei issues between clang and= binutils") Link: https://gcc.gnu.org/git/?p=3Dgcc.git;a=3Dcommit;h=3D98416dbb0a62579d4= a7a4a76bab51b5b52fec2cd [0] Link: https://lore.kernel.org/all/20230308220842.1231003-1-conor@kernel.org= [1] Link: https://lore.kernel.org/all/20230223220546.52879-1-conor@kernel.org [= 2] Link: https://lore.kernel.org/all/20230725170405.251011-1-xingmingzheng@isc= as.ac.cn Signed-off-by: Mingzheng Xing --- v2: - Update the Kconfig help text and commit message. - Add considerations for low version gcc case. Sorry for the formatting error on my mailing list reply. arch/riscv/Kconfig | 23 +++++++++++++---------- 1 file changed, 13 insertions(+), 10 deletions(-) diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 4c07b9189c86..08afd47de157 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -570,24 +570,27 @@ config TOOLCHAIN_HAS_ZIHINTPAUSE config TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI def_bool y # https://sourceware.org/git/?p=3Dbinutils-gdb.git;a=3Dcommit;h=3Daed4428= 6efa8ae8717a77d94b51ac3614e2ca6dc - depends on AS_IS_GNU && AS_VERSION >=3D 23800 + # https://gcc.gnu.org/git/?p=3Dgcc.git;a=3Dcommit;h=3D98416dbb0a62579d4a7= a4a76bab51b5b52fec2cd + depends on GCC_VERSION >=3D 120100 || (AS_IS_GNU && AS_VERSION >=3D 23800) help - Newer binutils versions default to ISA spec version 20191213 which - moves some instructions from the I extension to the Zicsr and Zifencei - extensions. + Binutils-2.38 and GCC-12.1.0 bump default ISA spec to newer version + 20191213 which moves some instructions from the I extension to the + Zicsr and Zifencei extensions. =20 config TOOLCHAIN_NEEDS_OLD_ISA_SPEC def_bool y depends on TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI # https://github.com/llvm/llvm-project/commit/22e199e6afb1263c943c0c0d449= 8694e15bf8a16 - depends on CC_IS_CLANG && CLANG_VERSION < 170000 + # https://gcc.gnu.org/git/?p=3Dgcc.git;a=3Dcommit;h=3Db03be74bad08c382da4= 7e048007a78fa3fb4ef49 + depends on (CC_IS_CLANG && CLANG_VERSION < 170000) || \ + (CC_IS_GCC && GCC_VERSION < 110100) help - Certain versions of clang do not support zicsr and zifencei via -march - but newer versions of binutils require it for the reasons noted in the - help text of CONFIG_TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI. This + Certain versions of clang (or GCC) do not support zicsr and zifencei via + -march but newer versions of binutils require it for the reasons noted + in the help text of CONFIG_TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI. This option causes an older ISA spec compatible with these older versions - of clang to be passed to GAS, which has the same result as passing zicsr - and zifencei to -march. + of clang (or GCC) to be passed to GAS, which has the same result as + passing zicsr and zifencei to -march. =20 config FPU bool "FPU support" --=20 2.34.1