From patchwork Tue Feb 28 21:54:33 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?q?Heiko_St=C3=BCbner?= X-Patchwork-Id: 13155287 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 5E141C64EC7 for ; Tue, 28 Feb 2023 21:55:00 +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-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:Message-Id:Date:Subject:Cc :To:From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References: List-Owner; bh=m4/XUYuqFMzTs6vb9DkvG4QaMf3IxaDY0VsGk1jdtKI=; b=BxX7bNoIqZynpG AyFhXFbalbR80Q42evDLQmbAhEViuzHMy09JHetHhW0u09EDXD0/xoczdHWEgPIP36c+FtMSdrcsN DgXtyTDyLMPrxXO+p7ePNdV9eWmRJyMOXUjf7MbPgxdFatUmUqu+g64v3TyB0GEvoh85Qv1j1ga5V VstbaRiPZ+S15ZrtbPdEqFXG3z7eA0XTBlxnV0/ZAuUaoBH1RBp/VCizHgoT1zAkaXWCTZUggEgiY Cuh7iqvB4+QmiX6406Squ/eyjWa/eR6twDAl2Le5dZuu1an22n1xhQNhaB0KGIYTx3m4foz+fraQ6 vIDbbxAolaRnCvCAgTrA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1pX7vx-00EOai-6V; Tue, 28 Feb 2023 21:54:53 +0000 Received: from gloria.sntech.de ([185.11.138.130]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1pX7vr-00EOWs-KH for linux-riscv@lists.infradead.org; Tue, 28 Feb 2023 21:54:49 +0000 Received: from ip5b412258.dynamic.kabel-deutschland.de ([91.65.34.88] helo=phil.lan) by gloria.sntech.de with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1pX7vm-0005hs-FY; Tue, 28 Feb 2023 22:54:42 +0100 From: Heiko Stuebner To: palmer@dabbelt.com Cc: linux-riscv@lists.infradead.org, samuel@sholland.org, guoren@kernel.org, christoph.muellner@vrull.eu, heiko@sntech.de, conor.dooley@microchip.com, linux-kernel@vger.kernel.org, Heiko Stuebner Subject: [PATCH RFC 0/2] RISC-V: T-Head vector handling Date: Tue, 28 Feb 2023 22:54:33 +0100 Message-Id: <20230228215435.3366914-1-heiko@sntech.de> X-Mailer: git-send-email 2.39.0 MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230228_135447_724477_0274FD55 X-CRM114-Status: GOOD ( 11.34 ) 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: , Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org From: Heiko Stuebner As is widely known the T-Head C9xx cores used for example in the Allwinner D1 implement an older non-ratified variant of the vector spec. While userspace will probably have a lot more problems implementing support for both, on the kernel side the needed changes are actually somewhat small'ish and can be handled via alternatives somewhat nicely. With this patchset I could run the same userspace program (picked from some riscv-vector-test repository) that does some vector additions on both qemu and a d1-nezha board. On both platforms it ran sucessfully and even produced the same results. As can be seen in the todo list, there are 2 places where the changed SR_VS location still needs to be handled in the next revision (assembly + ALTERNATIVES + constants + probably stringify resulted in some grey hair so far already) ToDo: - follow along with the base vector patchset - handle SR_VS access in _save_context and _secondary_start_sbi Heiko Stuebner (2): RISC-V: define the elements of the VCSR vector CSR RISC-V: add T-Head vector errata handling arch/riscv/Kconfig.erratas | 13 +++ arch/riscv/errata/thead/errata.c | 32 ++++++ arch/riscv/include/asm/csr.h | 31 +++++- arch/riscv/include/asm/errata_list.h | 62 +++++++++++- arch/riscv/include/asm/vector.h | 139 +++++++++++++++++++++++++-- 5 files changed, 261 insertions(+), 16 deletions(-)