Received: by 2002:a25:ab43:0:0:0:0:0 with SMTP id u61csp3315977ybi; Mon, 17 Jun 2019 21:58:01 -0700 (PDT) X-Google-Smtp-Source: APXvYqxoYOCrbyhkDccGpOJU5NdhKNP/4lAcbxxZt2/ypBw/rw3ucioxBNrr4wVlFGLTPO4gyjv3 X-Received: by 2002:a17:90a:2486:: with SMTP id i6mr2912810pje.125.1560833881473; Mon, 17 Jun 2019 21:58:01 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1560833881; cv=none; d=google.com; s=arc-20160816; b=vwHLYhYADtbsd1kh0IqndvoI3II2rFMiszRYaSWFLaQS2Z6RFS0v7ouIsBXRZMQF1p TAmfBta9MtvkHpcPpq+PTR2acj3baHCOR1Zmyk2/lHdx6eqtqx8C73WzikncQphn8H1Q XNIpace4u2jT+0kaGDcm2qAhV+gB5zbTKDR4SRCrrSpGpsoOpw4t7MUQi7krFufWUkyQ Trg7U/vAU1qCGDtV7zS9NjElB45WaVIFeuQJm+ye0Fk1SCdD8+7I12BnfIVAzB2ZC6AJ 8eIgl8+UigNhO0BxW/TByykCymsuyeV9lubWcDJz+1XupsvN7s1QbmfKsbqWogXlAN+P PF7A== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:user-agent:in-reply-to :content-disposition:mime-version:references:message-id:subject:cc :to:from:date:dkim-signature; bh=VlzBE0sxq/sIdQz5gRKjAAaIz8+KWuKdMmytYn1UrgA=; b=oeaFmFpmlIqC+pv9EAD3zVJzHqX/D7gbNJzzoJrIhEa5vZ6mqZzMdbuyKmB9Kgahef RegWikJDXkiR9fUZRKietZe0iw68owU+Brt2+bGYgztB3guL+gloARx2Z2a0RVpZkyKd 6VNLec/attu1XelY+2EZg/YcyekpEWvPwM+7QIvKbfuqujB5w8eTZm9xVK5uyvPPmzpO fBv20Hog0kBFEXxa3BAhFIcL3OTW/eQSxtlPeKWNG7akYqiTccNqzBYUxDGBAwtoFfbl bZiUzRDgkWxAUEBa+i1jqFx5sMK3ectLxfCduskJ6FH6h7fCKiESCPqcFxg83QkwIfws h+7Q== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=mLARzcNd; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id i95si11654644plb.106.2019.06.17.21.57.45; Mon, 17 Jun 2019 21:58:01 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=mLARzcNd; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728575AbfFRE4W (ORCPT + 99 others); Tue, 18 Jun 2019 00:56:22 -0400 Received: from mail.kernel.org ([198.145.29.99]:46392 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725900AbfFRE4V (ORCPT ); Tue, 18 Jun 2019 00:56:21 -0400 Received: from localhost (unknown [122.178.226.130]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 639A12085A; Tue, 18 Jun 2019 04:56:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1560833781; bh=p/1WgzjyDGLLUL8w56446SHwaaWDO2rQKvXQxt/cSOE=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=mLARzcNdUkEGgZ6QGRCy1f8/hT1C52+XCSQoCJtQofiim3IBDE61VXQboKn7OSnQB kl9r5cEauFP3BdsUQkFjXA9tz42XRh9QCI6hydwe+7mFnSxAy39pQskRuJfSc+Eo9X tHV3NswGQd/50ocwL2XpOHmRGf5i66vfC7zJt4LE= Date: Tue, 18 Jun 2019 10:23:12 +0530 From: Vinod Koul To: Srinivas Kandagatla Cc: dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, sricharan@codeaurora.org Subject: Re: [PATCH] dmaengine: qcom-bam: fix circular buffer handling Message-ID: <20190618045312.GK2962@vkoul-mobl> References: <20190614142012.31384-1-srinivas.kandagatla@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190614142012.31384-1-srinivas.kandagatla@linaro.org> User-Agent: Mutt/1.11.3 (2019-02-01) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 14-06-19, 15:20, Srinivas Kandagatla wrote: > For some reason arguments to most of the circular buffers > macros are used in reverse, tail is used for head and vice versa. > > This leads to bam thinking that there is an extra descriptor at the > end and leading to retransmitting descriptor which was not scheduled > by any driver. This happens after MAX_DESCRIPTORS (4096) are scheduled > and done, so most of the drivers would not notice this, unless they are > heavily using bam dma. Originally found this issue while testing > SoundWire over SlimBus on DB845c which uses DMA very heavily for > read/writes. Applied and copied stable, thanks -- ~Vinod