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=-2.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_PASS,T_DKIMWL_WL_HIGH,URIBL_BLOCKED, USER_AGENT_MUTT autolearn=ham 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 02464C43144 for ; Fri, 29 Jun 2018 07:37:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A54C027B79 for ; Fri, 29 Jun 2018 07:37:20 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="ZPEOEjwB" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A54C027B79 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933267AbeF2HhT (ORCPT ); Fri, 29 Jun 2018 03:37:19 -0400 Received: from mail.kernel.org ([198.145.29.99]:34520 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752082AbeF2HhR (ORCPT ); Fri, 29 Jun 2018 03:37:17 -0400 Received: from localhost (unknown [122.167.66.23]) (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 B00F327A88; Fri, 29 Jun 2018 07:37:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1530257836; bh=SKF0zyKxp2RgYDUsXa/g9yEkf9UDEEXNxyixbvib1B0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=ZPEOEjwBpYdzd6313DbHuIu9JpTbldLsLak0+LcMKDxGba+fPFRGe50rdYt76LZDW V+tAzl2DauNoDN0Vf+Ftep1XBXm7zQ1NgUP20uTZgmhmpk/+7fjLJ2hnYaiwoAmi5K NqPYjjpZUIRTMYbosmBsm6IORC6Nv5If6Rv/Iaww= Date: Fri, 29 Jun 2018 13:07:07 +0530 From: Vinod To: Andrea Merello Cc: dan.j.williams@intel.com, michal.simek@xilinx.com, appana.durga.rao@xilinx.com, dmaengine@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Rob Herring , Mark Rutland , devicetree@vger.kernel.org, Radhey Shyam Pandey Subject: Re: [PATCH v3 4/5] dmaengine: xilinx_dma: autodetect whether the HW supports scatter-gather Message-ID: <20180629073707.GZ22377@vkoul-mobl> References: <20180625092724.22164-1-andrea.merello@gmail.com> <20180625092724.22164-4-andrea.merello@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180625092724.22164-4-andrea.merello@gmail.com> User-Agent: Mutt/1.9.2 (2017-12-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 25-06-18, 11:27, Andrea Merello wrote: > The AXIDMA and CDMA HW can be either direct-access or scatter-gather > version. These are SW incompatible. > > The driver can handle both version: a DT property was used to ^^^^ versions > tell the driver whether to assume the HW is is scatter-gather mode. ^^^^^ is in? > > This patch makes the driver to autodetect this information. The DT > property is not required anymore. > > No changes for VDMA. > > Cc: Rob Herring > Cc: Mark Rutland > Cc: devicetree@vger.kernel.org > Cc: Radhey Shyam Pandey > Signed-off-by: Andrea Merello > Reviewed-by: Radhey Shyam Pandey > --- > Changes in v2: > - autodetect only in !VDMA case > Changes in v3: > - cc DT maintainers/ML > --- > drivers/dma/xilinx/xilinx_dma.c | 14 ++++++++++---- > 1 file changed, 10 insertions(+), 4 deletions(-) > > diff --git a/drivers/dma/xilinx/xilinx_dma.c b/drivers/dma/xilinx/xilinx_dma.c > index 7f0ab904b749..43fcc71ff287 100644 > --- a/drivers/dma/xilinx/xilinx_dma.c > +++ b/drivers/dma/xilinx/xilinx_dma.c > @@ -86,6 +86,7 @@ > #define XILINX_DMA_DMASR_DMA_DEC_ERR BIT(6) > #define XILINX_DMA_DMASR_DMA_SLAVE_ERR BIT(5) > #define XILINX_DMA_DMASR_DMA_INT_ERR BIT(4) > +#define XILINX_DMA_DMASR_SG_MASK BIT(3) > #define XILINX_DMA_DMASR_IDLE BIT(1) > #define XILINX_DMA_DMASR_HALTED BIT(0) > #define XILINX_DMA_DMASR_DELAY_MASK GENMASK(31, 24) > @@ -406,7 +407,6 @@ struct xilinx_dma_config { > * @dev: Device Structure > * @common: DMA device structure > * @chan: Driver specific DMA channel > - * @has_sg: Specifies whether Scatter-Gather is present or not > * @mcdma: Specifies whether Multi-Channel is present or not > * @flush_on_fsync: Flush on frame sync > * @ext_addr: Indicates 64 bit addressing is supported by dma device > @@ -426,7 +426,6 @@ struct xilinx_dma_device { > struct device *dev; > struct dma_device common; > struct xilinx_dma_chan *chan[XILINX_DMA_MAX_CHANS_PER_DEVICE]; > - bool has_sg; > bool mcdma; > u32 flush_on_fsync; > bool ext_addr; > @@ -2393,7 +2392,6 @@ static int xilinx_dma_chan_probe(struct xilinx_dma_device *xdev, > > chan->dev = xdev->dev; > chan->xdev = xdev; > - chan->has_sg = xdev->has_sg; > chan->desc_pendingcount = 0x0; > chan->ext_addr = xdev->ext_addr; > /* This variable ensures that descriptors are not > @@ -2486,6 +2484,15 @@ static int xilinx_dma_chan_probe(struct xilinx_dma_device *xdev, > chan->stop_transfer = xilinx_dma_stop_transfer; > } > > + /* check if SG is enabled (only for AXIDMA and CDMA) */ > + if (xdev->dma_config->dmatype != XDMA_TYPE_VDMA) { > + if (dma_ctrl_read(chan, XILINX_DMA_REG_DMASR) & > + XILINX_DMA_DMASR_SG_MASK) why not read this for VDMA too, will it return false? > + chan->has_sg = true; > + dev_dbg(chan->dev, "ch %d: SG %s\n", chan->id, > + chan->has_sg ? "enabled" : "disabled"); this debug print can be removed -- ~Vinod