From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mauro Carvalho Chehab Subject: Re: [PATCH] media: s5p-mfc: Fix memdev DMA configuration Date: Wed, 5 Dec 2018 07:31:02 -0200 Message-ID: <20181205073102.310edc76@coco.lan> References: <20180914121931eucas1p14292ee983fd9b4bb21968dffa303dde8~UQ3utL6mj2689726897eucas1p15@eucas1p1.samsung.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20180914121931eucas1p14292ee983fd9b4bb21968dffa303dde8~UQ3utL6mj2689726897eucas1p15-MHMrYXj8g+pqW5MlFJXMulaTQe2KTcn/@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Marek Szyprowski Cc: Rob Herring , a.hajda-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org, Sylwester Nawrocki , Smitha T Murthy , kamil-MZ2JYD8fkKLYtjvyW6yDsg@public.gmane.org, iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, jtp.park-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org, kyungmin.park-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org, Robin Murphy , linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-media-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: iommu@lists.linux-foundation.org Em Fri, 14 Sep 2018 14:19:29 +0200 Marek Szyprowski escreveu: > Hi Robin, > > On 2018-09-12 18:45, Robin Murphy wrote: > > Having of_reserved_mem_device_init() forcibly reconfigure DMA for all > > callers, potentially overriding the work done by a bus-specific > > .dma_configure method earlier, is at best a bad idea and at worst > > actively harmful. If drivers really need virtual devices to own > > dma-coherent memory, they should explicitly configure those devices > > based on the appropriate firmware node as they create them. > > > > It looks like the only driver not passing in a proper OF platform device > > is s5p-mfc, so move the rogue of_dma_configure() call into that driver > > where it logically belongs. > > > > CC: Smitha T Murthy > > CC: Marek Szyprowski > > CC: Rob Herring > > Signed-off-by: Robin Murphy > > Right, after recent cleanup dma ops initialization, MFC driver is > a better place for calling of_dma_configure() on virtual devices. > > Reviewed-by: Marek Szyprowski This patch seems to fit better via OF/DT tree. Not sure if it was merged there yet. In any case: Acked-by: Mauro Carvalho Chehab > > > --- > > drivers/media/platform/s5p-mfc/s5p_mfc.c | 7 +++++++ > > drivers/of/of_reserved_mem.c | 4 ---- > > 2 files changed, 7 insertions(+), 4 deletions(-) > > > > diff --git a/drivers/media/platform/s5p-mfc/s5p_mfc.c b/drivers/media/platform/s5p-mfc/s5p_mfc.c > > index 927a1235408d..77eb4a4511c1 100644 > > --- a/drivers/media/platform/s5p-mfc/s5p_mfc.c > > +++ b/drivers/media/platform/s5p-mfc/s5p_mfc.c > > @@ -1094,6 +1094,13 @@ static struct device *s5p_mfc_alloc_memdev(struct device *dev, > > child->dma_mask = dev->dma_mask; > > child->release = s5p_mfc_memdev_release; > > > > + /* > > + * The memdevs are not proper OF platform devices, so in order for them > > + * to be treated as valid DMA masters we need a bit of a hack to force > > + * them to inherit the MFC node's DMA configuration. > > + */ > > + of_dma_configure(child, dev->of_node, true); > > + > > if (device_add(child) == 0) { > > ret = of_reserved_mem_device_init_by_idx(child, dev->of_node, > > idx); > > diff --git a/drivers/of/of_reserved_mem.c b/drivers/of/of_reserved_mem.c > > index 895c83e0c7b6..4ef6f4485335 100644 > > --- a/drivers/of/of_reserved_mem.c > > +++ b/drivers/of/of_reserved_mem.c > > @@ -350,10 +350,6 @@ int of_reserved_mem_device_init_by_idx(struct device *dev, > > mutex_lock(&of_rmem_assigned_device_mutex); > > list_add(&rd->list, &of_rmem_assigned_device_list); > > mutex_unlock(&of_rmem_assigned_device_mutex); > > - /* ensure that dma_ops is set for virtual devices > > - * using reserved memory > > - */ > > - of_dma_configure(dev, np, true); > > > > dev_info(dev, "assigned reserved memory node %s\n", rmem->name); > > } else { > > Best regards Thanks, Mauro