From patchwork Sun Jan 29 13:24:30 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: John Keeping X-Patchwork-Id: 9544063 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 4475960488 for ; Sun, 29 Jan 2017 13:33:12 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 371DE27D76 for ; Sun, 29 Jan 2017 13:33:12 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 2BED627F88; Sun, 29 Jan 2017 13:33:12 +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=-1.8 required=2.0 tests=BAYES_00,DKIM_SIGNED, T_DKIM_INVALID autolearn=no version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [65.50.211.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id EC0AF27D76 for ; Sun, 29 Jan 2017 13:33:11 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.87 #1 (Red Hat Linux)) id 1cXpbT-0001vt-Kv; Sun, 29 Jan 2017 13:33:11 +0000 Received: from dougal.metanate.com ([90.155.101.14] helo=metanate.com) by bombadil.infradead.org with esmtps (Exim 4.87 #1 (Red Hat Linux)) id 1cXpUD-0003sE-3K; Sun, 29 Jan 2017 13:25:48 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=simple/simple; d=metanate.com; s=stronger; h=References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From; bh=xws/JyPZNBY0rNgc2envLT7+oaQEKTCboL8ByeHyCUI=; b=mG3JlwF3VfZt11hgtF5sPlUFXXrMx0Wqy6yxw4loT2RflpLVqrXuEf+gVUAOPlvqDUYbQPbmXxwVjeDeAOhPj2Je64nNkuWgEVluhz2ijreFp3eK2TcFebfNkCGU+zJZoOKH6P04b5LjxEml8S9ttXdfwJ8+MCfag6v1ILaLXBv89tLEVHdNFJ0BgAsUNYc525ZrsJ78N/TnY31FkUcmSBz5qUVaQ4P9P09Lu1yvsoAL96efFA3m6IIyUxZhFjTno2cBOUPCtMGmF9nzx/NkkNkrVqYdvq+vcZXbuW2IFlGodM5RziTUlHdmX7kb6IXYgra4LLRSfijZV7uBW08Ysw==; Received: from johnkeeping.plus.com ([81.174.171.191] helo=localhost.localdomain) by shrek.metanate.com with esmtpsa (TLSv1.2:DHE-RSA-AES128-GCM-SHA256:128) (Exim 4.83_RC2) (envelope-from ) id 1cXpTh-000362-Fs; Sun, 29 Jan 2017 13:25:09 +0000 From: John Keeping To: Mark Yao Subject: [PATCH v3 10/24] drm/rockchip: dw-mipi-dsi: don't assume buffer is aligned Date: Sun, 29 Jan 2017 13:24:30 +0000 Message-Id: <20170129132444.25251-11-john@metanate.com> X-Mailer: git-send-email 2.11.0.197.gb556de5.dirty In-Reply-To: <20170129132444.25251-1-john@metanate.com> References: <20170129132444.25251-1-john@metanate.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20170129_052541_523532_95D9EED7 X-CRM114-Status: UNSURE ( 9.19 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-rockchip@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: Upstream kernel work for Rockchip platforms List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-rockchip@lists.infradead.org, John Keeping , Chris Zhong , linux-arm-kernel@lists.infradead.org MIME-Version: 1.0 Sender: "Linux-rockchip" Errors-To: linux-rockchip-bounces+patchwork-linux-rockchip=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP By dereferencing the MIPI command buffer as a u32* we rely on it being correctly aligned on ARM, but this may not be the case. Copy it into a stack variable that will be correctly aligned. Signed-off-by: John Keeping Reviewed-by: Chris Zhong --- v3: - Add Chris' Reviewed-by Unchanged in v2 drivers/gpu/drm/rockchip/dw-mipi-dsi.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/rockchip/dw-mipi-dsi.c b/drivers/gpu/drm/rockchip/dw-mipi-dsi.c index 03fc096fe1bd..ddbc037e7ced 100644 --- a/drivers/gpu/drm/rockchip/dw-mipi-dsi.c +++ b/drivers/gpu/drm/rockchip/dw-mipi-dsi.c @@ -607,10 +607,10 @@ static int dw_mipi_dsi_dcs_short_write(struct dw_mipi_dsi *dsi, static int dw_mipi_dsi_dcs_long_write(struct dw_mipi_dsi *dsi, const struct mipi_dsi_msg *msg) { - const u32 *tx_buf = msg->tx_buf; - int len = msg->tx_len, pld_data_bytes = sizeof(*tx_buf), ret; + const u8 *tx_buf = msg->tx_buf; + int len = msg->tx_len, pld_data_bytes = sizeof(u32), ret; u32 hdr_val = GEN_HDATA(msg->tx_len) | GEN_HTYPE(msg->type); - u32 remainder = 0; + u32 remainder; u32 val; if (msg->tx_len < 3) { @@ -621,12 +621,14 @@ static int dw_mipi_dsi_dcs_long_write(struct dw_mipi_dsi *dsi, while (DIV_ROUND_UP(len, pld_data_bytes)) { if (len < pld_data_bytes) { + remainder = 0; memcpy(&remainder, tx_buf, len); dsi_write(dsi, DSI_GEN_PLD_DATA, remainder); len = 0; } else { - dsi_write(dsi, DSI_GEN_PLD_DATA, *tx_buf); - tx_buf++; + memcpy(&remainder, tx_buf, pld_data_bytes); + dsi_write(dsi, DSI_GEN_PLD_DATA, remainder); + tx_buf += pld_data_bytes; len -= pld_data_bytes; }