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=-9.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 EBFBAC432C0 for ; Thu, 28 Nov 2019 16:50:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C531C21787 for ; Thu, 28 Nov 2019 16:50:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="QdfKOwx2" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727212AbfK1Quc (ORCPT ); Thu, 28 Nov 2019 11:50:32 -0500 Received: from mail-pl1-f195.google.com ([209.85.214.195]:46129 "EHLO mail-pl1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727008AbfK1QuV (ORCPT ); Thu, 28 Nov 2019 11:50:21 -0500 Received: by mail-pl1-f195.google.com with SMTP id k20so7341936pll.13 for ; Thu, 28 Nov 2019 08:50:20 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=Ve1daf/mMGyyV9VtqaD9VZ+drFrdziUeyzqFEa1bEX8=; b=QdfKOwx2OJabOfCqE3mEGZgTrv2/gWtfc9aPsAegxShDlcJFxfod9xbR8qUpaUSrKA lN+swYwLnlgLgrSviR4JWJihJonMpuhy7wXqHAnmUInK0mv8323jJHcCIE4QGYw2lsZH q8oKAydylvf86RpUa4wuc+K76Mk8Yr0z0Bp0mJmTZlYpbNQelJuy2w772CJ365QXJ0hK sJQROf9qRH30ngnifsT6wcvVfOsqo0OHmynT5HckidI/ew0Z7ofqawUkSOMQO/qEzAcp C1v01meXvQFJRnBwVFxCG2S+pRY6T9NkCdPIOWPZspbfiwTUWLVf5twPkpqtU/z0nBQI nIVw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=Ve1daf/mMGyyV9VtqaD9VZ+drFrdziUeyzqFEa1bEX8=; b=UAnEfE6FnZ3FuniphjCOKucm3Oo24yN2EHjQt9HyOOoaj8Y6NhZyYUqtuFIx7HFtOL 2Ol07gtDNIhKGg6SoeTCjddBOQ5TwEvaLPfHOA+aUT4BZjkUqw2VMtZmwbL3/d7jKSHH Toto+ph0SSrQ2T5KuXtY277nUgQ8wdFK/paSssQmBZEUuXSgJuETMH+znvCCDFZBhwPA 3VKbXw2/TJlXipaH1K4Ir8wQRAFOODFzZy9AeVb6WiQEeD4x39KMDGZzQJOhFtRzj86v 5U7FIBOLQ4M9FpAGxKFk21R5PTMCjq9POYJ6U2vS+zxHxVRxng7L4Ds++7g2AIpFQx+w ATTQ== X-Gm-Message-State: APjAAAXXaM10q2gmlCJ9ygmRGugU1uyXUbmOGSKr18c2ah+Xm6zEvuSP +zYbsuqSjarPaGMqYAOvCoLK6w== X-Google-Smtp-Source: APXvYqwF9EpUID9uoRJaTP7XOptfqBdu8zh2mx1l+skezdxU/+nVZEZ0krSH/BIt3st7U3Is4b6ZnQ== X-Received: by 2002:a17:902:b181:: with SMTP id s1mr10698227plr.62.1574959820186; Thu, 28 Nov 2019 08:50:20 -0800 (PST) Received: from xps15.cg.shawcable.net (S0106002369de4dac.cg.shawcable.net. [68.147.8.254]) by smtp.gmail.com with ESMTPSA id a15sm2450343pfh.169.2019.11.28.08.50.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 28 Nov 2019 08:50:19 -0800 (PST) From: Mathieu Poirier To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: [stable 4.19][PATCH 17/17] dmaengine: stm32-dma: check whether length is aligned on FIFO threshold Date: Thu, 28 Nov 2019 09:50:02 -0700 Message-Id: <20191128165002.6234-18-mathieu.poirier@linaro.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20191128165002.6234-1-mathieu.poirier@linaro.org> References: <20191128165002.6234-1-mathieu.poirier@linaro.org> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Pierre-Yves MORDRET commit cc832dc8e32785a730ba07c3a357e17c201a5df8 upstream When a period length is not multiple of FIFO some data may be stuck within FIFO. Burst/FIFO Threshold/Period or buffer length check has to be hardened In any case DMA will grant any request from client but will degraded any parameters whether awkward. Signed-off-by: Pierre-Yves MORDRET Signed-off-by: Vinod Koul Cc: stable # 4.19 Signed-off-by: Mathieu Poirier --- drivers/dma/stm32-dma.c | 20 ++++++-------------- 1 file changed, 6 insertions(+), 14 deletions(-) diff --git a/drivers/dma/stm32-dma.c b/drivers/dma/stm32-dma.c index 379e8d534e61..4903a408fc14 100644 --- a/drivers/dma/stm32-dma.c +++ b/drivers/dma/stm32-dma.c @@ -308,20 +308,12 @@ static bool stm32_dma_fifo_threshold_is_allowed(u32 burst, u32 threshold, static bool stm32_dma_is_burst_possible(u32 buf_len, u32 threshold) { - switch (threshold) { - case STM32_DMA_FIFO_THRESHOLD_FULL: - if (buf_len >= STM32_DMA_MAX_BURST) - return true; - else - return false; - case STM32_DMA_FIFO_THRESHOLD_HALFFULL: - if (buf_len >= STM32_DMA_MAX_BURST / 2) - return true; - else - return false; - default: - return false; - } + /* + * Buffer or period length has to be aligned on FIFO depth. + * Otherwise bytes may be stuck within FIFO at buffer or period + * length. + */ + return ((buf_len % ((threshold + 1) * 4)) == 0); } static u32 stm32_dma_get_best_burst(u32 buf_len, u32 max_burst, u32 threshold, -- 2.17.1