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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 05D62C4320A for ; Fri, 30 Jul 2021 13:11:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DB6A160462 for ; Fri, 30 Jul 2021 13:11:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238941AbhG3NLX (ORCPT ); Fri, 30 Jul 2021 09:11:23 -0400 Received: from perceval.ideasonboard.com ([213.167.242.64]:53600 "EHLO perceval.ideasonboard.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238939AbhG3NLU (ORCPT ); Fri, 30 Jul 2021 09:11:20 -0400 Received: from pendragon.ideasonboard.com (62-78-145-57.bb.dnainternet.fi [62.78.145.57]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id AED1889B; Fri, 30 Jul 2021 15:11:12 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1627650672; bh=BaDdgFohF0w/+xJcUh1JwfdiwXY9VL37FZXcaq52Hsk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=PYYuwPVB2EfhXKZNQ5wM9N73zw9fkaz3N0Sfbq73f3i/GoxRtvbcVIGT+ZQnwk9/O rYCHgX+8lAgS2stDda1cQ7Q+RKEDNoRjY6pvPqOiFTIke9qhSbzw2BkpHh82SzRhzf 1WFhoTva8XtwzgfBUTC0J7Ubrnhxb2CPY2YXKMoo= Date: Fri, 30 Jul 2021 16:11:04 +0300 From: Laurent Pinchart To: Dafna Hirschfeld Cc: linux-media@vger.kernel.org, linux-renesas-soc@vger.kernel.org, Helen Koike , Shuah Khan Subject: Re: [PATCH] media: vimc: Add support for contiguous DMA buffers Message-ID: References: <20210730001939.30769-1-laurent.pinchart+renesas@ideasonboard.com> <40a1fed8-456e-97c5-9aa7-715a4a4c816b@collabora.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <40a1fed8-456e-97c5-9aa7-715a4a4c816b@collabora.com> Precedence: bulk List-ID: X-Mailing-List: linux-renesas-soc@vger.kernel.org Hi Dafna, On Fri, Jul 30, 2021 at 02:35:20PM +0200, Dafna Hirschfeld wrote: > On 30.07.21 02:19, Laurent Pinchart wrote: > > The vimc driver is used for testing purpose, and some test use cases > > involve sharing buffers with a consumer device. Consumers often require > > DMA contiguous memory, which vimc doesn't currently support. This leads > > in the best case to usage of bounce buffers, which is very slow, and in > > the worst case in a complete failure. > > > > Add support for the dma-contig allocator in vimc to support those use > > cases properly. The allocator is selected through a new "allocator" > > module parameter, which defaults to vmalloc. > > > > Signed-off-by: Laurent Pinchart > > --- > > drivers/media/test-drivers/vimc/vimc-capture.c | 9 +++++++-- > > drivers/media/test-drivers/vimc/vimc-common.h | 2 ++ > > drivers/media/test-drivers/vimc/vimc-core.c | 10 ++++++++++ > > 3 files changed, 19 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/media/test-drivers/vimc/vimc-capture.c b/drivers/media/test-drivers/vimc/vimc-capture.c > > index 5e9fd902cd37..92b69a6529fb 100644 > > --- a/drivers/media/test-drivers/vimc/vimc-capture.c > > +++ b/drivers/media/test-drivers/vimc/vimc-capture.c > > @@ -7,6 +7,7 @@ > > > > #include > > #include > > +#include > > #include > > > > #include "vimc-common.h" > > @@ -423,14 +424,18 @@ static struct vimc_ent_device *vimc_cap_add(struct vimc_device *vimc, > > /* Initialize the vb2 queue */ > > q = &vcap->queue; > > q->type = V4L2_BUF_TYPE_VIDEO_CAPTURE; > > - q->io_modes = VB2_MMAP | VB2_DMABUF | VB2_USERPTR; > > + q->io_modes = VB2_MMAP | VB2_DMABUF; > > maybe to be on the safe side VB2_DMABUF should be set only if vimc_allocator==1 ? Why so ? vb2-vmalloc can import dma-bufs. > > + if (vimc_allocator != 1) > > maybe define a macro instead of `1` ? Good idea. > > + q->io_modes |= VB2_USERPTR; > > q->drv_priv = vcap; > > q->buf_struct_size = sizeof(struct vimc_cap_buffer); > > q->ops = &vimc_cap_qops; > > - q->mem_ops = &vb2_vmalloc_memops; > > + q->mem_ops = vimc_allocator == 1 > > + ? &vb2_dma_contig_memops : &vb2_vmalloc_memops; > > q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC; > > q->min_buffers_needed = 2; > > q->lock = &vcap->lock; > > + q->dev = v4l2_dev->dev; > > > > ret = vb2_queue_init(q); > > if (ret) { > > diff --git a/drivers/media/test-drivers/vimc/vimc-common.h b/drivers/media/test-drivers/vimc/vimc-common.h > > index a289434e75ba..b77939123501 100644 > > --- a/drivers/media/test-drivers/vimc/vimc-common.h > > +++ b/drivers/media/test-drivers/vimc/vimc-common.h > > @@ -35,6 +35,8 @@ > > > > #define VIMC_PIX_FMT_MAX_CODES 8 > > > > +extern unsigned int vimc_allocator; > > + > > /** > > * vimc_colorimetry_clamp - Adjust colorimetry parameters > > * > > diff --git a/drivers/media/test-drivers/vimc/vimc-core.c b/drivers/media/test-drivers/vimc/vimc-core.c > > index 4b0ae6f51d76..7badcecb7aed 100644 > > --- a/drivers/media/test-drivers/vimc/vimc-core.c > > +++ b/drivers/media/test-drivers/vimc/vimc-core.c > > @@ -5,6 +5,7 @@ > > * Copyright (C) 2015-2017 Helen Koike > > */ > > > > +#include > > #include > > #include > > #include > > @@ -15,6 +16,12 @@ > > > > #include "vimc-common.h" > > > > +unsigned int vimc_allocator; > > +module_param_named(allocator, vimc_allocator, uint, 0444); > > +MODULE_PARM_DESC(allocator, " memory allocator selection, default is 0.\n" > > + "\t\t 0 == vmalloc\n" > > + "\t\t 1 == dma-contig"); > > + > > There is a section 'Module options' in vimc.rst. So a doc should be added there. OK, I'll update that. > > #define VIMC_MDEV_MODEL_NAME "VIMC MDEV" > > > > #define VIMC_ENT_LINK(src, srcpad, sink, sinkpad, link_flags) { \ > > @@ -278,6 +285,9 @@ static int vimc_probe(struct platform_device *pdev) > > > > tpg_set_font(font->data); > > > > + if (vimc_allocator == 1) > > + dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32)); > > + > > vimc = kzalloc(sizeof(*vimc), GFP_KERNEL); > > if (!vimc) > > return -ENOMEM; > > -- Regards, Laurent Pinchart