From patchwork Mon Mar 27 12:13:00 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arnd Bergmann X-Patchwork-Id: 13189131 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 90861C77B61 for ; Mon, 27 Mar 2023 12:14:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232761AbjC0MO4 (ORCPT ); Mon, 27 Mar 2023 08:14:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33328 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232726AbjC0MOm (ORCPT ); Mon, 27 Mar 2023 08:14:42 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 56D3649E0; Mon, 27 Mar 2023 05:14:35 -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 ams.source.kernel.org (Postfix) with ESMTPS id DE820B8115E; Mon, 27 Mar 2023 12:14:33 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7B9C0C433EF; Mon, 27 Mar 2023 12:14:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1679919272; bh=ZhYG8JNUwjljPv9OKiF3eMGP7VJHxmj1d7o6guSf4No=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=PBdwMSfV6WhGkWO4GD6yfcHOXcUpefrDC/+txqBn1K1TXjh6vtxTQLHjgNJ0FEkt0 8kEYArEe0oN6TTz55A/ouqhYMm5G10akCJmXzW/muCfT8GBSGN5Uni+3VEARUH4Auc H3B65ricYeSXsGj53UrQTCcr95NZtYK/45G5qbsvcFbKhYxNglRYB3Jv/RHrFzHtks DVdr6HivllSdF2l5dgd1hATA9JZvKqwXHc1koDjA6e60zts4nydXjlN/RqoC6otSSa Tq0Qb2MNzDbHG7RwE+Edr/TKARawLeFdDNo+IyVrlawBJzvWe5xP0tuqDo6AiiQKTk Trtj2/d6VSosQ== 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 04/21] microblaze: dma-mapping: skip extra DMA flushes Date: Mon, 27 Mar 2023 14:13:00 +0200 Message-Id: <20230327121317.4081816-5-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-parisc@vger.kernel.org From: Arnd Bergmann The microblaze dma_sync_* implementation uses the same function for both _for_cpu() and _for_device(), which is inconsistent with other architectures and slightly more expensive. Split it up into separate functions and skip the parts that are not needed: - on dma_sync_*_for_cpu(..., DMA_TO_DEVICE), skip the second writeback, which does nothing. - on dma_sync_*_for_cpu(..., DMA_BIDIRECTIONAL), only invalidate the cache to clear out cache lines that got loaded speculatively, but skip the extraneous writeback. Signed-off-by: Arnd Bergmann --- arch/microblaze/kernel/dma.c | 22 ++++++++++++---------- 1 file changed, 12 insertions(+), 10 deletions(-) diff --git a/arch/microblaze/kernel/dma.c b/arch/microblaze/kernel/dma.c index 04d091ade417..b4c4e45fd45e 100644 --- a/arch/microblaze/kernel/dma.c +++ b/arch/microblaze/kernel/dma.c @@ -14,8 +14,8 @@ #include #include -static void __dma_sync(phys_addr_t paddr, size_t size, - enum dma_data_direction direction) +void arch_sync_dma_for_device(phys_addr_t paddr, size_t size, + enum dma_data_direction dir) { switch (direction) { case DMA_TO_DEVICE: @@ -30,14 +30,16 @@ static void __dma_sync(phys_addr_t paddr, size_t size, } } -void arch_sync_dma_for_device(phys_addr_t paddr, size_t size, - enum dma_data_direction dir) -{ - __dma_sync(paddr, size, dir); -} - void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size, enum dma_data_direction dir) { - __dma_sync(paddr, size, dir); -} + switch (direction) { + case DMA_TO_DEVICE: + break; + case DMA_BIDIRECTIONAL: + case DMA_FROM_DEVICE: + invalidate_dcache_range(paddr, paddr + size); + break; + default: + BUG(); + }}