657776d47b
[ Upstream commit a622310f7f0185da02e42cdb06475f533efaae60 ]
OMAP processors support 32 channels but there is no check or
inspect this except booting a device and looking at dmesg reports
of not available channels.
Recently some more subsystems with DMA (aes1+2) were added filling
the list of dma channels beyond the limit of 32 (even if other
parameters indicate 96 or 128 channels). This leads to random
subsystem failures i(e.g. mcbsp for audio) after boot or boot
messages that DMA can not be initialized.
Another symptom is that
/sys/kernel/debug/dmaengine/summary
has 32 entries and does not show all required channels.
Fix by disabling unused (on the GTA04 hardware) mcspi1...4.
Each SPI channel allocates 4 DMA channels rapidly filling
the available ones.
Disabling unused SPI modules on the OMAP3 SoC may also save
some energy (has not been checked).
Fixes: c312f066314e ("ARM: dts: omap3: Migrate AES from hwmods to sysc-omap2")
Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
[re-enabled aes2, improved commit subject line]
Signed-off-by: Andreas Kemnade <andreas@kemnade.info>
Message-Id: <20230113211151.2314874-1-andreas@kemnade.info>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Sasha Levin <sashal@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.