Hi Steve, Am Mittwoch, den 10.09.2014, 18:17 -0700 schrieb Steve Longerbeam: [...] > On 09/09/2014 10:40 AM, Philipp Zabel wrote: [...] > > I have in the meantime started to > > implement everything that has a source or destination selector in the > > Frame Synchronization Unit (FSU) as media entity. I wonder which of > > these parts should reasonably be unified into a single entity: [...] > > SMFC0 > > SMFC1 > > SMFC2 > > SMFC3 > > I don't really see the need for an SMFC entity. The SMFC control can > be integrated into the CSI subdev.
Granted, this is currently is a theoretical question, but could we handle a single MIPI link that carries two or more virtual channels with different MIPI IDs this way? > > IC preprocessor (input to VF and ENC, if I understood correctly) > > IC viewfinder task (scaling, csc) > > IC encoding task > > IC post processing task > > I see either three different IC subdev entities (IC prpenc, IC prpvf, > IC pp), or a single IC entity with three sink pads for each IC task. The former could work, the latter won't allow to have pre and post processing on separate pipelines. > > IRT viewfinder task (rotation) > > IRT encoding task > > IRT post processing task > > well, the IRT is really just a submodule enable bit, I see no need > for an IRT subdev, in fact IRT has already been folded into ipu-ic.c > as a simple submodule enable/disable. Rotation support can be > implemented as part of the IC entities. My current understanding is that the IRT is strictly a mem2mem device using its own DMA channels, which can be channel-linked to the IC (and other blocks) in various ways. > > VDIC (deinterlacing, combining) > > I am thinking VDIC support can be part of the IC prpvf entity (well, > combining is not really on my radar, I haven't given that much thought). > > > (and probably some entry for DP/DC/DMFC for the direct > > viewfinder path) > > Ugh, I've been ignoring that path as well. Freescale's BSP releases > and sample code from their SDK's have no example code for the > direct-to-DP/DC/DMFC camera viewfinder path, so given the quality > of the imx TRM, this could be a challenge to implement. Have you > gotten this path to work? Not yet, no. > > I suppose the SMFC channels need to be separate because they can belong > > to different pipelines (and each entity can only belong to one). > > I see the chosen SMFC channel as an internal decision by the > CSI subdev. Can we handle multiple outputs from a single CSI this way? > > The three IC task entities could probably be combined with their > > corresponding IRT task entity somehow, but that would be at the cost of > > not being able to tell the kernel whether to rotate before or after > > scaling, which might be useful when handling chroma subsampled formats. > > I'm fairly sure IC rotation must always occur _after_ scaling. I.e. > raw frames are first passed through IC prpenc/prpvf/pp for scaling/CSC, > then EOF completion of that task is hardware linked to IRT. There could be good reasons to do the rotation on the input side, for example when upscaling or when the output is 4:2:2 subsampled. At least the FSU registers suggest that channel linking the rotator before the IC is possible. This probably won't be useful for the capture path in most cases, but it might be for rotated playback. > > I have put my current state up here: > > > > git://git.pengutronix.de/git/pza/linux.git test/nitrogen6x-ipu-media > > > > So far I've captured video through the SMFC on a Nitrogen6X board with > > OV5652 parallel camera with this. > > Thanks Phillip, I'll take a look! Sounds like a good place to start. > I assume this is with the video mux entity and CSI driver? I.e. no > IC entity support yet for scaling, CSC, or rotation. Yes, exactly. regards Philipp -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
