mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-05-09 10:11:52 -04:00
cbbe883330
Without this, the driver for the BCM2835 SPI controller uses interrupt mode instead of DMA mode, incurring a significant performance penalty. The Foundation's device tree has had these attributes for years, but for some reason they were never upstreamed. They were originally contributed by Noralf Trønnes and Martin Sperl: https://github.com/raspberrypi/linux/commit/25f3e064afc8 https://github.com/raspberrypi/linux/commit/e0edb52b47e6 The DREQ numbers 6 and 7 are documented in section 4.2.1.3 of: https://www.raspberrypi.org/app/uploads/2012/02/BCM2835-ARM-Peripherals.pdf Tested-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de> Signed-off-by: Lukas Wunner <lukas@wunner.de> Reviewed-by: Eric Anholt <eric@anholt.net> Reviewed-by: Martin Sperl <kernel@martin.sperl.org> Signed-off-by: Stefan Wahren <wahrenst@gmx.net> Cc: Martin Sperl <kernel@martin.sperl.org> Cc: Noralf Trønnes <noralf@tronnes.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.