From patchwork Sun May 8 17:56:45 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Jonathan Cameron X-Patchwork-Id: 12842589 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 935A4C433EF for ; Sun, 8 May 2022 19:13:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230484AbiEHTRG (ORCPT ); Sun, 8 May 2022 15:17:06 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40384 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244144AbiEHSBF (ORCPT ); Sun, 8 May 2022 14:01:05 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B316E558C for ; Sun, 8 May 2022 10:57:14 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 4F6066128E for ; Sun, 8 May 2022 17:57:14 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C891BC385B0; Sun, 8 May 2022 17:57:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1652032633; bh=rMvAwjFCDrTL76/ErwDYUWdtFLiUmu7PtbCE6mWRZ8g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=n/T5nR2fWvfH+Ijs7z7Ar4LKlxCcMAfs7OIXmUWcTSZiPF/KGVmAkIsla7SzVilNy seml0mu71FONqXt5cjRliOqk/7PMU3pyc8BdHeir8sKT1R0uF6eM38FT4+Jf8aF3/I XvE3h0KHZePbfiApCssY1OSSE3M8MaPaMAILQwcrP1TIyQdCGQVJpBP0hTGUUr5wFQ O1sZe125jiTrzOvigxbm0Xu8y27Zp5ZCHwfYYzGSrPI2wUuNQEg+q1m1ezeQDmEIpG VfS+fDDNsi3T/fO+VgnRlG80ZJg1mz/ZCEfAgQ3k1zizWhR2UMt+jKrN4h8aeyMD9m Zls5n1aU0H7nA== From: Jonathan Cameron To: linux-iio@vger.kernel.org Cc: 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 , =?utf-8?q?M=C3=A5rten_Lindahl?= , Matt Ranostay , Matt Ranostay , Michael Hennerich , Michael Welling , Mugilraj Dhavachelvan , Navin Sankar Velliangiri , =?utf-8?q?Nuno_S=C3=A1?= , Paul Cercueil , Phil Reid , Puranjay Mohan , Ricardo Ribalda , Robert Jones , Rui Miguel Silva , Sean Nyekjaer , Tomas Melin , Tomislav Denis , =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= , Jonathan Cameron Subject: [PATCH v2 65/92] iio: frequency: ad9523: Fix alignment for DMA safety Date: Sun, 8 May 2022 18:56:45 +0100 Message-Id: <20220508175712.647246-66-jic23@kernel.org> X-Mailer: git-send-email 2.36.0 In-Reply-To: <20220508175712.647246-1-jic23@kernel.org> References: <20220508175712.647246-1-jic23@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org 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. Updated help text to 'may' require buffers to be in their own cacheline. Fixes: cd1678f96329 ("iio: frequency: New driver for AD9523 SPI Low Jitter Clock Generator") Signed-off-by: Jonathan Cameron Acked-by: Nuno Sá --- drivers/iio/frequency/ad9523.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/iio/frequency/ad9523.c b/drivers/iio/frequency/ad9523.c index a0f92c336fc4..31c97f9f2c1b 100644 --- a/drivers/iio/frequency/ad9523.c +++ b/drivers/iio/frequency/ad9523.c @@ -287,13 +287,13 @@ struct ad9523_state { struct mutex lock; /* - * DMA (thus cache coherency maintenance) requires the - * transfer buffers to live in their own cache lines. + * DMA (thus cache coherency maintenance) may require that + * transfer buffers live in their own cache lines. */ union { __be32 d32; u8 d8[4]; - } data[2] ____cacheline_aligned; + } data[2] __aligned(IIO_DMA_MINALIGN); }; static int ad9523_read(struct iio_dev *indio_dev, unsigned int addr)