c8a0d6b256
Zeroing the page registers at the end of every paged transaction is just overhead (40% overhead on a 1-register access, 25% on a 4-register transaction). According to the spec a peripheral that supports paging should only use the values in the page registers if the address is paged (address bit 15 set). The core SoundWire code always writes the page registers at the start of a paged transaction so there will never be a transaction that uses the stale values from a previous paged transaction. For peripherals that need large amounts of data to be transferred, for example firmware or filter coefficients, the overhead of page register zeroing can become quite significant. Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com> Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Link: https://lore.kernel.org/r/20230123164949.245898-2-rf@opensource.cirrus.com Signed-off-by: Vinod Koul <vkoul@kernel.org> |
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| Documentation | ||
| LICENSES | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| io_uring | ||
| ipc | ||
| kernel | ||
| lib | ||
| mm | ||
| net | ||
| rust | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| .rustfmt.toml | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
README
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.