From patchwork Wed Dec 7 13:17:40 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vladimir Murzin X-Patchwork-Id: 9464457 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 D79CD60459 for ; Wed, 7 Dec 2016 13:18:08 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C45861FF28 for ; Wed, 7 Dec 2016 13:18:08 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id B84AE2843C; Wed, 7 Dec 2016 13:18:08 +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=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI 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 3118E1FF28 for ; Wed, 7 Dec 2016 13:18:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751900AbcLGNSF (ORCPT ); Wed, 7 Dec 2016 08:18:05 -0500 Received: from foss.arm.com ([217.140.101.70]:36972 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751372AbcLGNSE (ORCPT ); Wed, 7 Dec 2016 08:18:04 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 0EA7A707; Wed, 7 Dec 2016 05:18:04 -0800 (PST) Received: from bc-a7-2-11.euhpc.arm.com. (bc-a7-2-11.euhpc.arm.com [10.6.2.107]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 4F7883F477; Wed, 7 Dec 2016 05:18:03 -0800 (PST) From: Vladimir Murzin To: dmaengine@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org, Robin Murphy , Vinod Koul Subject: [PATCH] dmaengine: pl330: do not generate unaligned access Date: Wed, 7 Dec 2016 13:17:40 +0000 Message-Id: <1481116660-27837-1-git-send-email-vladimir.murzin@arm.com> X-Mailer: git-send-email 2.0.0 Sender: dmaengine-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP When PL330 is used with !MMU the following fault is seen: Unhandled fault: alignment exception (0x801) at 0x8f26a002 Internal error: : 801 [#1] ARM Modules linked in: CPU: 0 PID: 640 Comm: dma0chan0-copy0 Not tainted 4.8.0-6a82063-clean+ #1600 Hardware name: ARM-Versatile Express task: 8f1baa80 task.stack: 8e6fe000 PC is at _setup_req+0x4c/0x350 LR is at 0x8f2cbc00 pc : [<801ea538>] lr : [<8f2cbc00>] psr: 60000093 sp : 8e6ffdc0 ip : 00000000 fp : 00000000 r10: 00000000 r9 : 8f2cba10 r8 : 8f2cbc00 r7 : 80000013 r6 : 8f21a050 r5 : 8f21a000 r4 : 8f2ac800 r3 : 8e6ffe18 r2 : 00944251 r1 : ffffffbc r0 : 8f26a000 Flags: nZCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment none Control: 00c5387c Process dma0chan0-copy0 (pid: 640, stack limit = 0x8e6fe210) Stack: (0x8e6ffdc0 to 0x8e700000) fdc0: 00000001 60000093 00000000 8f2cba10 8f26a000 00000004 8f0ae000 8f2cbc00 fde0: 8f0ae000 8f2ac800 8f21a000 8f21a050 80000013 8f2cbc00 8f2cba10 00000000 fe00: 60000093 801ebca0 8e6ffe18 000013ff 40000093 00000000 00944251 8f2ac800 fe20: a0000013 8f2b1320 00001986 00000000 00000001 000013ff 8f1e4f00 8f2cba10 fe40: 8e6fff6c 801e9044 00000003 00000000 fef98c80 002faf07 8e6ffe7c 00000000 fe60: 00000002 00000000 00001986 8f1f158d 8f1e4f00 80568de4 00000002 00000000 fe80: 00001986 8f1f53ff 40000001 80580500 8f1f158d 8001e00c 00000000 cfdfdfdf fea0: fdae2a25 00000001 00000004 8e6fe000 00000008 00000010 00000000 00000005 fec0: 8f2b1330 8f2b1334 8e6ffe80 8e6ffe8c 00001986 00000000 8f21a014 00000001 fee0: 8e6ffe60 8e6ffe78 00000002 00000000 000013ff 00000001 80568de4 8f1e8018 ff00: 0000158d 8055ec30 00000001 803f6b00 00001986 8f2cba10 fdae2a25 00000001 ff20: 8f1baca8 8e6fff24 8e6fff24 00000000 8e6fff24 ac6f3037 00000000 00000000 ff40: 00000000 8e6fe000 8f1e4f40 00000000 8f1e4f40 8f1e4f00 801e84ec 00000000 ff60: 00000000 00000000 00000000 80031714 dfdfdfcf 00000000 dfdfdfcf 8f1e4f00 ff80: 00000000 8e6fff84 8e6fff84 00000000 8e6fff90 8e6fff90 8e6fffac 8f1e4f40 ffa0: 80031640 00000000 00000000 8000f548 00000000 00000000 00000000 00000000 ffc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 ffe0: 00000000 00000000 00000000 00000000 00000013 00000000 dfdfdfcf cfdfdfdf [<801ea538>] (_setup_req) from [<801ebca0>] (pl330_tasklet+0x41c/0x490) [<801ebca0>] (pl330_tasklet) from [<801e9044>] (dmatest_func+0xb58/0x149c) [<801e9044>] (dmatest_func) from [<80031714>] (kthread+0xd4/0xec) [<80031714>] (kthread) from [<8000f548>] (ret_from_fork+0x14/0x2c) Code: e3a03001 e3e01043 e5c03001 e59d3048 (e5802002) This happens because _emit_{ADDH,MOV,GO) accessing to unaligned data while writing to buffer. Fix it with writing to buffer byte by byte. Cc: Robin Murphy Cc: Vinod Koul Signed-off-by: Vladimir Murzin Reviewed-by: Robin Murphy Tested-by: Robin Murphy --- drivers/dma/pl330.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c index 030fe05..e4c1ba7 100644 --- a/drivers/dma/pl330.c +++ b/drivers/dma/pl330.c @@ -570,7 +570,8 @@ static inline u32 _emit_ADDH(unsigned dry_run, u8 buf[], buf[0] = CMD_DMAADDH; buf[0] |= (da << 1); - *((__le16 *)&buf[1]) = cpu_to_le16(val); + buf[1] = val; + buf[2] = val >> 8; PL330_DBGCMD_DUMP(SZ_DMAADDH, "\tDMAADDH %s %u\n", da == 1 ? "DA" : "SA", val); @@ -724,7 +725,10 @@ static inline u32 _emit_MOV(unsigned dry_run, u8 buf[], buf[0] = CMD_DMAMOV; buf[1] = dst; - *((__le32 *)&buf[2]) = cpu_to_le32(val); + buf[2] = val; + buf[3] = val >> 8; + buf[4] = val >> 16; + buf[5] = val >> 24; PL330_DBGCMD_DUMP(SZ_DMAMOV, "\tDMAMOV %s 0x%x\n", dst == SAR ? "SAR" : (dst == DAR ? "DAR" : "CCR"), val); @@ -899,10 +903,11 @@ static inline u32 _emit_GO(unsigned dry_run, u8 buf[], buf[0] = CMD_DMAGO; buf[0] |= (ns << 1); - buf[1] = chan & 0x7; - - *((__le32 *)&buf[2]) = cpu_to_le32(addr); + buf[2] = addr; + buf[3] = addr >> 8; + buf[4] = addr >> 16; + buf[5] = addr >> 24; return SZ_DMAGO; }