From patchwork Mon Mar 27 12:13:07 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arnd Bergmann X-Patchwork-Id: 13189119 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 244F3C7619A for ; Mon, 27 Mar 2023 12:16:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232719AbjC0MQj (ORCPT ); Mon, 27 Mar 2023 08:16:39 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35686 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232700AbjC0MQM (ORCPT ); Mon, 27 Mar 2023 08:16:12 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 21FD244AC; Mon, 27 Mar 2023 05:15:34 -0700 (PDT) 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 B1278611F5; Mon, 27 Mar 2023 12:15:33 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id ECBF0C433EF; Mon, 27 Mar 2023 12:15:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1679919333; bh=1A9PPhpjfn5VxBSmEZUVZ96wOnXUnzHwhEr/+6UxMII=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ZTcyGdTSTyjUcBoLSVeACST/PtG6gZO3O0XJKQPppvSvNB4NDcy90mHMF4gJPiNS6 dNtpCw1Tg4EZtsG9wUbybuw0872LTI9FUQllw/7Q76rCvz6Crnc81KUI9Kj4chNtUZ csalhGjvFzfmW3DiLJ6yzIpVXX+f5lcRxoFKXzIm876A40pKei6+o+8NXVAEYBZqzo s4oPjpuA8RpmeGU6lv0FlQ6gA3tl8++a/WzT9oNtEmsVj2YTsrbo7DHFpEIVM4/NkV v133TD824709IDedq8WaO7uGv2weYLR4T+0csPE1290Z1QSEI0fkOubzH+lLl8W9RM VLW1WwaNQGF9g== From: Arnd Bergmann To: linux-kernel@vger.kernel.org Cc: Arnd Bergmann , Vineet Gupta , Russell King , Neil Armstrong , Linus Walleij , Catalin Marinas , Will Deacon , Guo Ren , Brian Cain , Geert Uytterhoeven , Michal Simek , Thomas Bogendoerfer , Dinh Nguyen , Stafford Horne , Helge Deller , Michael Ellerman , Christophe Leroy , Paul Walmsley , Palmer Dabbelt , Rich Felker , John Paul Adrian Glaubitz , "David S. Miller" , Max Filippov , Christoph Hellwig , Robin Murphy , Lad Prabhakar , Conor Dooley , linux-snps-arc@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-oxnas@groups.io, linux-csky@vger.kernel.org, linux-hexagon@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-mips@vger.kernel.org, linux-openrisc@vger.kernel.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-riscv@lists.infradead.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, linux-xtensa@linux-xtensa.org Subject: [PATCH 11/21] mips: dma-mapping: skip invalidating before bidirectional DMA Date: Mon, 27 Mar 2023 14:13:07 +0200 Message-Id: <20230327121317.4081816-12-arnd@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230327121317.4081816-1-arnd@kernel.org> References: <20230327121317.4081816-1-arnd@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org From: Arnd Bergmann Some architectures that need to invalidate buffers after bidirectional DMA because of speculative prefetching only do a simpler writeback before that DMA, while architectures that don't need to do the second invalidate tend to have a combined writeback+invalidate before the DMA. The behavior on mips is slightly inconsistent, as it always does the invalidation before bidirectional DMA and conditionally does it a second time. In order to make the behavior the same as the rest, change it so that there is exactly one invalidation here, either before or after the DMA. Signed-off-by: Arnd Bergmann --- arch/mips/mm/dma-noncoherent.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/arch/mips/mm/dma-noncoherent.c b/arch/mips/mm/dma-noncoherent.c index 3c4fc97b9f39..b4350faf4f1e 100644 --- a/arch/mips/mm/dma-noncoherent.c +++ b/arch/mips/mm/dma-noncoherent.c @@ -65,7 +65,11 @@ static inline void dma_sync_virt_for_device(void *addr, size_t size, dma_cache_inv((unsigned long)addr, size); break; case DMA_BIDIRECTIONAL: - dma_cache_wback_inv((unsigned long)addr, size); + if (IS_ENABLED(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU) && + cpu_needs_post_dma_flush()) + dma_cache_wback((unsigned long)addr, size); + else + dma_cache_wback_inv((unsigned long)addr, size); break; default: BUG();