From patchwork Mon Nov 4 20:03:52 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sui Jingfeng X-Patchwork-Id: 13861965 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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (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 CF1EAD1BDEB for ; Mon, 4 Nov 2024 20:04:14 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 564BC10E4C3; Mon, 4 Nov 2024 20:04:12 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (1024-bit key; unprotected) header.d=linux.dev header.i=@linux.dev header.b="tsNzNLon"; dkim-atps=neutral Received: from out-185.mta0.migadu.com (out-185.mta0.migadu.com [91.218.175.185]) by gabe.freedesktop.org (Postfix) with ESMTPS id 4D1EB10E4C4 for ; Mon, 4 Nov 2024 20:04:11 +0000 (UTC) X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1730750649; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=6+Cctltnj8jUTfRPzXWg7X11ZIlWeCkuZhPa7klvD+M=; b=tsNzNLonLnVwGYjHKHR5pndwa0CTcCHa1fkmIv1OZoDAGgf2SOAzTYcs1AW9APE7KXii7X rywSqhbS0+AEi2917D4rrYRiSnWpUHUXJlU5aNJHsE3DnmEpVI9sxJ8x3dE01Gxe7gCX2b ebJRVJE19zFB/IS3KSC1VwpJUZ+xfmQ= From: Sui Jingfeng To: Lucas Stach , Russell King , Christian Gmeiner Cc: David Airlie , Simona Vetter , etnaviv@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Sui Jingfeng Subject: [etnaviv-next v2 1/3] drm/etnaviv: Drop offset in page manipulation Date: Tue, 5 Nov 2024 04:03:52 +0800 Message-Id: <20241104200354.656525-2-sui.jingfeng@linux.dev> In-Reply-To: <20241104200354.656525-1-sui.jingfeng@linux.dev> References: <20241104200354.656525-1-sui.jingfeng@linux.dev> MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" The 'offset' data member of the 'struct scatterlist' denotes the offset into a SG entry in bytes. But under drm subsystem, there has nearly NO drivers that actually tough the 'offset' data member of SG anymore. Especially for drivers that could contact with drm/etnaviv. This means that all DMA addresses that sg_dma_address() gives us will be PAGE_SIZE aligned, in other words, sg->offset will always equal to 0. Drop those compulations about the offset of SG entries can save some extra overhead. Signed-off-by: Sui Jingfeng --- drivers/gpu/drm/etnaviv/etnaviv_mmu.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/etnaviv/etnaviv_mmu.c b/drivers/gpu/drm/etnaviv/etnaviv_mmu.c index 8f33f111f9e8..ddb536d84c58 100644 --- a/drivers/gpu/drm/etnaviv/etnaviv_mmu.c +++ b/drivers/gpu/drm/etnaviv/etnaviv_mmu.c @@ -82,8 +82,8 @@ static int etnaviv_iommu_map(struct etnaviv_iommu_context *context, return -EINVAL; for_each_sgtable_dma_sg(sgt, sg, i) { - phys_addr_t pa = sg_dma_address(sg) - sg->offset; - unsigned int da_len = sg_dma_len(sg) + sg->offset; + phys_addr_t pa = sg_dma_address(sg); + unsigned int da_len = sg_dma_len(sg); unsigned int bytes = min_t(unsigned int, da_len, va_len); VERB("map[%d]: %08x %pap(%x)", i, iova, &pa, bytes);