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@@ -0,0 +1,39 @@
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+1) Support dma-buf memory management.
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+
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+In order to zero-copy import camera images into the 3D or display
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+pipelines, we need to export our buffers through dma-buf so that the
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+vc4 driver can import them. This may involve bringing in the VCSM
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+driver (which allows long-term management of regions of memory in the
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+space that the VPU reserved and Linux otherwise doesn't have access
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+to), or building some new protocol that allows VCSM-style management
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+of Linux's CMA memory.
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+
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+2) Avoid extra copies for padding of images.
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+
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+We expose V4L2_PIX_FMT_* formats that have a specified stride/height
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+padding in the V4L2 spec, but that padding doesn't match what the
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+hardware can do. If we exposed the native padding requirements
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+through the V4L2 "multiplanar" formats, the firmware would have one
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+less copy it needed to do.
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+
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+3) Port to ARM64
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+
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+The bulk_receive() does some manual cache flushing that are 32-bit ARM
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+only, which we should convert to proper cross-platform APIs.
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+
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+4) Convert to be a platform driver.
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+
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+Right now when the module probes, it tries to initialize VCHI and
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+errors out if it wasn't ready yet. If bcm2835-v4l2 was built in, then
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+VCHI generally isn't ready because it depends on both the firmware and
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+mailbox drivers having already loaded.
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+
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+We should have VCHI create a platform device once it's initialized,
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+and have this driver bind to it, so that we automatically load the
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+v4l2 module after VCHI loads.
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+
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+5) Drop the gstreamer workaround.
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+
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+This was a temporary workaround for a bug that was fixed mid-2014, and
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+we should remove it before stabilizing the driver.
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+
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Eric Anholt