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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CE785C433EF for ; Mon, 9 May 2022 09:09:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236467AbiEIJMa (ORCPT ); Mon, 9 May 2022 05:12:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38014 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237584AbiEIIih (ORCPT ); Mon, 9 May 2022 04:38:37 -0400 Received: from smtp2.axis.com (smtp2.axis.com [195.60.68.18]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3C5851F8F28 for ; Mon, 9 May 2022 01:34:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=axis.com; q=dns/txt; s=axis-central1; t=1652085282; x=1683621282; h=date:to:cc:subject:message-id:references:mime-version: content-transfer-encoding:in-reply-to:from; bh=7RhS52DYu2l/NpguTng0NvOzXM7WDN0hxKXMztDohzg=; b=Jtnv7k0RD9ZtKh/zkdnlFFLSR7Yk/TQO/Ah24CThrtsLmNUAjtJgVLdy KXXiUCuV2Bhnq/RPgR3Da4PW2m+08ineaL/MniM7l2HEAMISVsZlm+3XK 1JbAXQiXx2cMMV/ZhwG6mLeWhA2W+c/+ZBjyJpdFB/J7313jxu+sGiga9 Ub3OGLCdCwa7yPw0YxEcc7w0ZJYL0M72UIhGg9EqgB7mZaKkSyjkY/Wdm sr66MKlVx+pcPgykIcwKLhlKOL65Mcu99IQuc4bcg8JrTutWlisoFk3aF /kF25XCPALYBQzYW2OlwtkHJz2EzRYQv6HgSfPAIYXgr22sZdZb/yL/M2 A==; Date: Mon, 9 May 2022 10:34:16 +0200 To: Jonathan Cameron CC: "linux-iio@vger.kernel.org" , Alexandru Lazar , Akinobu Mita , "Alexandru Tachici" , Antoniu Miclaus , Charles-Antoine Couret , Cosmin Tanislav , David Lechner , "Ivan Mikhaylov" , Jacopo Mondi , Jean-Baptiste Maneyrol , Lars-Peter Clausen , Marcelo Schmitt , =?iso-8859-1?Q?M=E5rten?= Lindahl , Matt Ranostay , Matt Ranostay , "Michael Hennerich" , Michael Welling , Mugilraj Dhavachelvan , "Navin Sankar Velliangiri" , Nuno =?iso-8859-1?Q?S=E1?= , Paul Cercueil , Phil Reid , Puranjay Mohan , "Ricardo Ribalda" , Robert Jones , "Rui Miguel Silva" , Sean Nyekjaer , "Tomas Melin" , Tomislav Denis , Uwe =?iso-8859-1?Q?Kleine-K=F6nig?= , "Jonathan Cameron" Subject: Re: [PATCH v2 29/92] iio: adc: ti-adc084s021: Fix alignment for DMA safety Message-ID: References: <20220508175712.647246-1-jic23@kernel.org> <20220508175712.647246-30-jic23@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20220508175712.647246-30-jic23@kernel.org> From: Marten Lindahl Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org On Sun, May 08, 2022 at 07:56:09PM +0200, Jonathan Cameron wrote: > From: Jonathan Cameron > > ____cacheline_aligned is an insufficient guarantee for non-coherent DMA > on platforms with 128 byte cachelines above L1. Switch to the updated > IIO_DMA_MINALIGN definition. > > Update the comment to include 'may'. > > Fixes: 3691e5a69449 ("iio: adc: add driver for the ti-adc084s021 chip") > Signed-off-by: Jonathan Cameron > Cc: Mårten Lindahl > Acked-by: Nuno Sá Acked-by: Mårten Lindahl > --- > drivers/iio/adc/ti-adc084s021.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/iio/adc/ti-adc084s021.c b/drivers/iio/adc/ti-adc084s021.c > index c9b5d9aec3dc..1f6e53832e06 100644 > --- a/drivers/iio/adc/ti-adc084s021.c > +++ b/drivers/iio/adc/ti-adc084s021.c > @@ -32,10 +32,10 @@ struct adc084s021 { > s64 ts __aligned(8); > } scan; > /* > - * DMA (thus cache coherency maintenance) requires the > + * DMA (thus cache coherency maintenance) may require the > * transfer buffers to live in their own cache line. > */ > - u16 tx_buf[4] ____cacheline_aligned; > + u16 tx_buf[4] __aligned(IIO_DMA_MINALIGN); > __be16 rx_buf[5]; /* First 16-bits are trash */ > }; > > -- > 2.36.0 >