From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A33CBC433DB for ; Mon, 1 Mar 2021 04:08:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6461364EE1 for ; Mon, 1 Mar 2021 04:08:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232616AbhCAEIR (ORCPT ); Sun, 28 Feb 2021 23:08:17 -0500 Received: from szxga07-in.huawei.com ([45.249.212.35]:13388 "EHLO szxga07-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232478AbhCAEIN (ORCPT ); Sun, 28 Feb 2021 23:08:13 -0500 Received: from DGGEMS407-HUB.china.huawei.com (unknown [172.30.72.59]) by szxga07-in.huawei.com (SkyGuard) with ESMTP id 4Dpmrq0xQxz7rVY; Mon, 1 Mar 2021 12:05:47 +0800 (CST) Received: from localhost.localdomain (10.67.165.24) by DGGEMS407-HUB.china.huawei.com (10.3.19.207) with Microsoft SMTP Server id 14.3.498.0; Mon, 1 Mar 2021 12:07:22 +0800 From: Hui Tang To: , , CC: , Subject: [PATCH] video: fbdev: fix use of 'dma_map_single' Date: Mon, 1 Mar 2021 12:05:09 +0800 Message-ID: <1614571509-40078-1-git-send-email-tanghui20@huawei.com> X-Mailer: git-send-email 2.8.1 MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.67.165.24] X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-fbdev@vger.kernel.org DMA_TO_DEVICE synchronisation must be done after the last modification of the memory region by the software and before it is handed off to the device. Signed-off-by: Hui Tang --- drivers/video/fbdev/grvga.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/video/fbdev/grvga.c b/drivers/video/fbdev/grvga.c index 24818b2..25ae9ef 100644 --- a/drivers/video/fbdev/grvga.c +++ b/drivers/video/fbdev/grvga.c @@ -435,6 +435,8 @@ static int grvga_probe(struct platform_device *dev) retval = -ENOMEM; goto dealloc_cmap; } + + memset((unsigned long *) virtual_start, 0, grvga_mem_size); } else { /* Allocate frambuffer memory */ unsigned long page; @@ -449,6 +451,7 @@ static int grvga_probe(struct platform_device *dev) goto dealloc_cmap; } + memset((unsigned long *) virtual_start, 0, grvga_mem_size); physical_start = dma_map_single(&dev->dev, (void *)virtual_start, grvga_mem_size, DMA_TO_DEVICE); /* Set page reserved so that mmap will work. This is necessary @@ -463,8 +466,6 @@ static int grvga_probe(struct platform_device *dev) par->fb_alloced = 1; } - memset((unsigned long *) virtual_start, 0, grvga_mem_size); - info->screen_base = (char __iomem *) virtual_start; info->fix.smem_start = physical_start; info->fix.smem_len = grvga_mem_size; -- 2.8.1