Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752092AbaBQJmK (ORCPT ); Mon, 17 Feb 2014 04:42:10 -0500 Received: from mail-la0-f52.google.com ([209.85.215.52]:41669 "EHLO mail-la0-f52.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751764AbaBQJmH (ORCPT ); Mon, 17 Feb 2014 04:42:07 -0500 MIME-Version: 1.0 In-Reply-To: <5301D7CD.5000405@metafoo.de> References: <1392465619-27614-1-git-send-email-sthokal@xilinx.com> <1392465619-27614-2-git-send-email-sthokal@xilinx.com> <20140217084316.GY10628@intel.com> <5301D7CD.5000405@metafoo.de> Date: Mon, 17 Feb 2014 15:12:05 +0530 X-Google-Sender-Auth: AUKkuKIxy3j5alLkjmKAFDyO9Cg Message-ID: Subject: Re: [PATCH v3 1/3] dma: Support multiple interleaved frames with non-contiguous memory From: Srikanth Thokala To: Lars-Peter Clausen Cc: Srikanth Thokala , Vinod Koul , dan.j.williams@intel.com, michal.simek@xilinx.com, Grant Likely , robh+dt@kernel.org, Levente Kurusa , andriy.shevchenko@linux.jf.intel.com, dmaengine@vger.kernel.org, linux-arm-kernel@lists.infradead.org, "linux-kernel@vger.kernel.org" , devicetree@vger.kernel.org Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Feb 17, 2014 at 3:05 PM, Lars-Peter Clausen wrote: > On 02/17/2014 10:29 AM, Srikanth Thokala wrote: >> >> On Mon, Feb 17, 2014 at 2:13 PM, Vinod Koul wrote: >>> >>> On Sat, Feb 15, 2014 at 05:30:17PM +0530, Srikanth Thokala wrote: >>>> >>>> The current implementation of interleaved DMA API support multiple >>>> frames only when the memory is contiguous by incrementing src_start/ >>>> dst_start members of interleaved template. >>>> >>>> But, when the memory is non-contiguous it will restrict slave device >>>> to not submit multiple frames in a batch. This patch handles this >>>> issue by allowing the slave device to send array of interleaved dma >>>> templates each having a different memory location. >>> >>> This seems to be missing the numbers of templates you are sending, >>> wouldnt this >>> require sending ARRAY_SiZE too? >>> >>> And why send double pointer? >> >> >> Array size is not required, when we pass the double pointer. The last >> element would be >> pointed to NULL and we could get the number of templates from this >> condition. >> Here is an example snippet, >> >> In slave device driver, >> >> struct dma_interleaved_template **xts; >> >> xts = kcalloc(frm_cnt+1, sizeof(struct >> dma_interleaved_template *), GFP_KERNEL); >> /* Error check for xts */ >> for (i = 0; i < frm_cnt; i++) { >> xts[i] = kmalloc(sizeof(struct >> dma_interleaved_template), GFP_KERNEL); >> /* Error check for xts[i] */ >> } >> xts[i] = NULL; >> >> In DMA engine driver, we could get the number of frames by, >> >> for (; xts[frmno] != NULL; frmno++); >> >> I felt this way is simpler than adding an extra argument to the API. >> Please let me know >> your opinion and suggest me a better way. > > > I think Vinod's suggestion of passing in an array of interleaved_templates > and the size of the array is better than what you are currently doing. Ok, Lars. I will update with this in my v4. Thanks. > > Btw. you also need to update the current implementations and users of the > API accordingly. Yes, I have updated them in this patch. Thanks Srikanth > > >> >>> >>> -- >>> ~Vinod >>> >>>> >>>> Signed-off-by: Srikanth Thokala >>>> --- >>>> Documentation/dmaengine.txt | 2 +- >>>> drivers/dma/imx-dma.c | 3 ++- >>>> drivers/dma/sirf-dma.c | 3 ++- >>>> drivers/media/platform/m2m-deinterlace.c | 2 +- >>>> include/linux/dmaengine.h | 6 +++--- >>>> 5 files changed, 9 insertions(+), 7 deletions(-) >>>> >>>> diff --git a/Documentation/dmaengine.txt b/Documentation/dmaengine.txt >>>> index 879b6e3..c642614 100644 >>>> --- a/Documentation/dmaengine.txt >>>> +++ b/Documentation/dmaengine.txt >>>> @@ -94,7 +94,7 @@ The slave DMA usage consists of following steps: >>>> size_t period_len, enum dma_data_direction direction); >>>> >>>> struct dma_async_tx_descriptor *(*device_prep_interleaved_dma)( >>>> - struct dma_chan *chan, struct dma_interleaved_template >>>> *xt, >>>> + struct dma_chan *chan, struct dma_interleaved_template >>>> **xts, >>>> unsigned long flags); >>>> >>>> The peripheral driver is expected to have mapped the scatterlist >>>> for >>>> diff --git a/drivers/dma/imx-dma.c b/drivers/dma/imx-dma.c >>>> index 6f9ac20..e2c52ce 100644 >>>> --- a/drivers/dma/imx-dma.c >>>> +++ b/drivers/dma/imx-dma.c >>>> @@ -954,12 +954,13 @@ static struct dma_async_tx_descriptor >>>> *imxdma_prep_dma_memcpy( >>>> } >>>> >>>> static struct dma_async_tx_descriptor *imxdma_prep_dma_interleaved( >>>> - struct dma_chan *chan, struct dma_interleaved_template *xt, >>>> + struct dma_chan *chan, struct dma_interleaved_template **xts, >>>> unsigned long flags) >>>> { >>>> struct imxdma_channel *imxdmac = to_imxdma_chan(chan); >>>> struct imxdma_engine *imxdma = imxdmac->imxdma; >>>> struct imxdma_desc *desc; >>>> + struct dma_interleaved_template *xt = *xts; >>>> >>>> dev_dbg(imxdma->dev, "%s channel: %d src_start=0x%llx >>>> dst_start=0x%llx\n" >>>> " src_sgl=%s dst_sgl=%s numf=%zu frame_size=%zu\n", >>>> __func__, >>>> diff --git a/drivers/dma/sirf-dma.c b/drivers/dma/sirf-dma.c >>>> index d4d3a31..b6a150b 100644 >>>> --- a/drivers/dma/sirf-dma.c >>>> +++ b/drivers/dma/sirf-dma.c >>>> @@ -509,12 +509,13 @@ sirfsoc_dma_tx_status(struct dma_chan *chan, >>>> dma_cookie_t cookie, >>>> } >>>> >>>> static struct dma_async_tx_descriptor *sirfsoc_dma_prep_interleaved( >>>> - struct dma_chan *chan, struct dma_interleaved_template *xt, >>>> + struct dma_chan *chan, struct dma_interleaved_template **xts, >>>> unsigned long flags) >>>> { >>>> struct sirfsoc_dma *sdma = dma_chan_to_sirfsoc_dma(chan); >>>> struct sirfsoc_dma_chan *schan = >>>> dma_chan_to_sirfsoc_dma_chan(chan); >>>> struct sirfsoc_dma_desc *sdesc = NULL; >>>> + struct dma_interleaved_template *xt = *xts; >>>> unsigned long iflags; >>>> int ret; >>>> >>>> diff --git a/drivers/media/platform/m2m-deinterlace.c >>>> b/drivers/media/platform/m2m-deinterlace.c >>>> index 6bb86b5..468110a 100644 >>>> --- a/drivers/media/platform/m2m-deinterlace.c >>>> +++ b/drivers/media/platform/m2m-deinterlace.c >>>> @@ -343,7 +343,7 @@ static void deinterlace_issue_dma(struct >>>> deinterlace_ctx *ctx, int op, >>>> ctx->xt->dst_sgl = true; >>>> flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT; >>>> >>>> - tx = dmadev->device_prep_interleaved_dma(chan, ctx->xt, flags); >>>> + tx = dmadev->device_prep_interleaved_dma(chan, &ctx->xt, flags); >>>> if (tx == NULL) { >>>> v4l2_warn(&pcdev->v4l2_dev, "DMA interleaved prep >>>> error\n"); >>>> return; >>>> diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h >>>> index c5c92d5..2f77a9a 100644 >>>> --- a/include/linux/dmaengine.h >>>> +++ b/include/linux/dmaengine.h >>>> @@ -675,7 +675,7 @@ struct dma_device { >>>> size_t period_len, enum dma_transfer_direction direction, >>>> unsigned long flags, void *context); >>>> struct dma_async_tx_descriptor *(*device_prep_interleaved_dma)( >>>> - struct dma_chan *chan, struct dma_interleaved_template >>>> *xt, >>>> + struct dma_chan *chan, struct dma_interleaved_template >>>> **xts, >>>> unsigned long flags); >>>> int (*device_control)(struct dma_chan *chan, enum dma_ctrl_cmd >>>> cmd, >>>> unsigned long arg); >>>> @@ -752,10 +752,10 @@ static inline struct dma_async_tx_descriptor >>>> *dmaengine_prep_dma_cyclic( >>>> } >>>> >>>> static inline struct dma_async_tx_descriptor >>>> *dmaengine_prep_interleaved_dma( >>>> - struct dma_chan *chan, struct dma_interleaved_template >>>> *xt, >>>> + struct dma_chan *chan, struct dma_interleaved_template >>>> **xts, >>>> unsigned long flags) >>>> { >>>> - return chan->device->device_prep_interleaved_dma(chan, xt, flags); >>>> + return chan->device->device_prep_interleaved_dma(chan, xts, >>>> flags); >>>> } >>>> >>>> static inline int dma_get_slave_caps(struct dma_chan *chan, struct >>>> dma_slave_caps *caps) >>>> -- >>>> 1.7.9.5 >>>> >>>> -- >>>> To unsubscribe from this list: send the line "unsubscribe dmaengine" in >>>> the body of a message to majordomo@vger.kernel.org >>>> More majordomo info at http://vger.kernel.org/majordomo-info.html >>> >>> >>> -- >>> -- >>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" >>> in >>> the body of a message to majordomo@vger.kernel.org >>> More majordomo info at http://vger.kernel.org/majordomo-info.html >>> Please read the FAQ at http://www.tux.org/lkml/ > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/