From patchwork Sat Jun 24 18:40:46 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: WANG Xuerui X-Patchwork-Id: 13291750 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 7772CEB64DA for ; Sat, 24 Jun 2023 18:41:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232332AbjFXSlQ (ORCPT ); Sat, 24 Jun 2023 14:41:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46834 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229623AbjFXSlP (ORCPT ); Sat, 24 Jun 2023 14:41:15 -0400 Received: from mailbox.box.xen0n.name (mail.xen0n.name [115.28.160.31]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 62557E6E; Sat, 24 Jun 2023 11:41:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=xen0n.name; s=mail; t=1687632067; bh=bAxZaycDbWfuwRvHTfXiVsCe0Y6mZrUxvMWuln5IK0A=; h=From:To:Cc:Subject:Date:From; b=TUd3908nen/qm/u4LMrb/IbpjtP0GyGXJ4vZM75NFB9EI5fa5kcnjfDRZNqWx7W70 47kma0fpv17iAHBRnA+P2ob6BsF3mSxBp8szaoYq6qa4pHxaPYECoW49d1tlmtNQ2R b7aFukYAbfEdbn7OJ7G4BWEZz4eslJZ/QNK+q71E= Received: from ld50.lan (unknown [101.88.25.181]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mailbox.box.xen0n.name (Postfix) with ESMTPSA id 61C78600B5; Sun, 25 Jun 2023 02:41:04 +0800 (CST) From: WANG Xuerui To: Huacai Chen Cc: WANG Rui , Xi Ruoyao , loongarch@lists.linux.dev, linux-kbuild@vger.kernel.org, llvm@lists.linux.dev, linux-kernel@vger.kernel.org, WANG Xuerui Subject: [PATCH v2 0/9] LoongArch: Preliminary ClangBuiltLinux enablement Date: Sun, 25 Jun 2023 02:40:46 +0800 Message-Id: <20230624184055.3000636-1-kernel@xen0n.name> X-Mailer: git-send-email 2.40.0 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org From: WANG Xuerui Hi, It's been a long time since the LoongArch port was upstreamed to LLVM, and there seems to be evidence that Linux was successfully built with Clang inside Loongson roughly around that time; however, a lot has changed since then, and the Linux/LoongArch codebase now makes use of more novel features that necessitate further work. (The enablement work is tracked at [1].) With this patch series and a patched LLVM/Clang/LLD ([2][3][4][5]), a working kernel can be built with `make LLVM=1`. Although currently support for CONFIG_RELOCATABLE and CONFIG_MODULE is still TODO, we've decided to post the series early to hopefully reduce the rebase burden. The series contains several useful cleanups anyway. Regarding how to merge this: because only Patch 8 is outside arch/loongarch, I'd prefer the series to get merged through Huacai's tree. The series applies cleanly on top of next-20230622. Thanks go to the ClangBuiltLinux team, and LoongArch toolchain maintainers from Loongson and the community alike; without your help this would come much later, if at all (my free time has been steadily dwindling this year already). Your comments are welcome! [1]: https://github.com/ClangBuiltLinux/linux/issues/1787 [2]: https://reviews.llvm.org/D153609 [3]: https://reviews.llvm.org/D138135 [4]: https://reviews.llvm.org/D150196 [5]: https://reviews.llvm.org/D153707 Changes in v2: - Merged the two FCSR-related patches, now using the same approach for assembly and C (given that the inline asm codepath cannot be removed right away), also change terminology: register "class" instead of "bank" - Restored signatures of invtlb wrappers for ease of rebase (potentially downstream product kernels?) - Removed -G0 switches altogether (turned out it's useless upon closer look) - Fix -mabi and -msoft-float handling in the CFLAGS patch; two more LLVM patches are now necessary (the [4] and [5] links above) but the original and correct CFLAGS arrangement now works WANG Rui (2): LoongArch: Calculate various sizes in the linker script LoongArch: extable: Also recognize ABI names of registers WANG Xuerui (7): LoongArch: Prepare for assemblers with proper FCSR class support LoongArch: Make the CPUCFG and CSR ops simple aliases of compiler built-ins LoongArch: Simplify the invtlb wrappers LoongArch: Remove all -G0 switches from CFLAGS LoongArch: Tweak CFLAGS for Clang compatibility LoongArch: Mark Clang LTO as working Makefile: Add loongarch target flag for Clang compilation arch/loongarch/Kconfig | 5 ++ arch/loongarch/Makefile | 10 ++-- arch/loongarch/include/asm/fpregdef.h | 7 +++ arch/loongarch/include/asm/gpr-num.h | 30 +++++++++++ arch/loongarch/include/asm/loongarch.h | 72 +++++++------------------- arch/loongarch/include/asm/tlb.h | 39 +++++++------- arch/loongarch/kernel/efi-header.S | 6 +-- arch/loongarch/kernel/head.S | 8 +-- arch/loongarch/kernel/traps.c | 2 +- arch/loongarch/kernel/vmlinux.lds.S | 7 +++ arch/loongarch/lib/dump_tlb.c | 6 +-- arch/loongarch/vdso/Makefile | 2 +- scripts/Makefile.clang | 1 + 13 files changed, 107 insertions(+), 88 deletions(-)