From patchwork Tue Apr 10 18:25:03 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sinan Kaya X-Patchwork-Id: 10333589 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 4AC2E60365 for ; Tue, 10 Apr 2018 18:25:16 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 3792227F3E for ; Tue, 10 Apr 2018 18:25:16 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 2905227F54; Tue, 10 Apr 2018 18:25:16 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.8 required=2.0 tests=BAYES_00,DKIM_SIGNED, MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI, T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8EFA327F3E for ; Tue, 10 Apr 2018 18:25:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751546AbeDJSZO (ORCPT ); Tue, 10 Apr 2018 14:25:14 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:53542 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751504AbeDJSZN (ORCPT ); Tue, 10 Apr 2018 14:25:13 -0400 Received: by smtp.codeaurora.org (Postfix, from userid 1000) id 2108160C65; Tue, 10 Apr 2018 18:25:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1523384713; bh=Ua3acgZnryQrtTzTjHqzVYdyxACYdgx2LTupnbkII/A=; h=From:To:Cc:Subject:Date:From; b=E8bwPq+2A8jUOnj2AJdJ9LuZifn1KiUsn6Qv2T5CZJLuHvI0NN/+IY+JuHu+7x2jm 7PoZQHpDs9lGBxbZyTmGcr3ShmbjvIFMFq0f5ndYVRjONdOYTi4SmVyye4sb3pU9MZ Oiv86ezQ7rP/Qj4w443U02VvTwC0O66zvROQpewM= Received: from drakthul.qualcomm.com (global_nat1_iad_fw.qualcomm.com [129.46.232.65]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: okaya@smtp.codeaurora.org) by smtp.codeaurora.org (Postfix) with ESMTPSA id CF3BA60274; Tue, 10 Apr 2018 18:25:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1523384712; bh=Ua3acgZnryQrtTzTjHqzVYdyxACYdgx2LTupnbkII/A=; h=From:To:Cc:Subject:Date:From; b=msUAvGUSbbtJ69mFaj1Wni/TkIKyZOdvRCvnvm9dMQ/RYBa08vxTBzJui0RMpzpmV 6+iDPhjpJ72XRKCwDaa9A6V0eHth46DuVaFR5rkuVoQV7NKmZ5EquvlkSr+41kFYEU 6HxWcWeYg27Hk+/Q/uTe3lEhV97SV92KQvmUaAxA= DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org CF3BA60274 Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=okaya@codeaurora.org From: Sinan Kaya To: amd-gfx@lists.freedesktop.org, timur@codeaurora.org, sulrich@codeaurora.org Cc: linux-arm-msm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Sinan Kaya , Alex Deucher , =?UTF-8?q?Christian=20K=C3=B6nig?= , "David (ChunMing) Zhou" , David Airlie , =?UTF-8?q?Michel=20D=C3=A4nzer?= , Tom St Denis , Felix Kuehling , Roger He , Monk Liu , Harish Kasiviswanathan , dri-devel@lists.freedesktop.org (open list:DRM DRIVERS), linux-kernel@vger.kernel.org (open list) Subject: [PATCH] drm/amdgpu: limit DMA size to PAGE_SIZE for scatter-gather buffers Date: Tue, 10 Apr 2018 14:25:03 -0400 Message-Id: <1523384705-3976-1-git-send-email-okaya@codeaurora.org> X-Mailer: git-send-email 2.7.4 MIME-Version: 1.0 Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Code is expecing to observe the same number of buffers returned from dma_map_sg() function compared to sg_alloc_table_from_pages(). This doesn't hold true universally especially for systems with IOMMU. IOMMU driver tries to combine buffers into a single DMA address as much as it can. The right thing is to tell the DMA layer how much combining IOMMU can do. Signed-off-by: Sinan Kaya --- drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c index e4bb435..02465cd 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c @@ -787,6 +787,8 @@ static int amdgpu_ttm_tt_pin_userptr(struct ttm_tt *ttm) enum dma_data_direction direction = write ? DMA_BIDIRECTIONAL : DMA_TO_DEVICE; + dma_set_max_seg_size(adev->dev, PAGE_SIZE); + r = sg_alloc_table_from_pages(ttm->sg, ttm->pages, ttm->num_pages, 0, ttm->num_pages << PAGE_SHIFT, GFP_KERNEL);