82b88d4da5
Set allow_cache_hints to 1 for the vb2_queue capture queue in the STM32MP15xx DCMI V4L2 driver. This allows us to allocate buffers with the V4L2_MEMORY_FLAG_NON_COHERENT set. On STM32MP15xx SoCs, this enables caching for this memory, which improves performance when being read from CPU. This change should be safe from race conditions since videobuf2 already invalidates or flushes the appropriate cache lines in its prepare() and finish() methods. Tested on a STM32MP157F SoC. Resulted in 4x buffer access speedup. Signed-off-by: Marek Vasut <marex@denx.de> Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.