Douglas Anderson 6d66507d9b spi: spi-geni-qcom: Don't wait to start 1st transfer if transmitting
If we're sending bytes over SPI, we know the FIFO is empty at the
start of the transfer.  There's no reason to wait for the interrupt
telling us to start--we can just start right away.  Then if we
transmit everything in one swell foop we don't even need to bother
listening for TX interrupts.

In a test of "flashrom -p ec -r /tmp/foo.bin" interrupts were reduced
from ~30560 to ~29730, about a 3% savings.

This patch looks bigger than it is because I moved a few functions
rather than adding a forward declaration.  The only actual change to
geni_spi_handle_tx() was to make it return a bool indicating if there
is more to tx.

Signed-off-by: Douglas Anderson <[email protected]>
Reviewed-by: Akash Asthana <[email protected]>
Reviewed-by: Bjorn Andersson <[email protected]>
Link: https://lore.kernel.org/r/20200912111716.1.Ied5e843fad0d6b733a1fb8bcfb364dd2fa889eb3@changeid
Signed-off-by: Mark Brown <[email protected]>
2020-09-14 15:50:16 +01:00
2020-09-06 17:11:40 -07:00

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.
S
Description
Linux kernel source tree
Readme
7.8 GiB
0 Stars 1 Watchers 0 Forks
Languages
C 96.9%
Assembly 0.9%
Rust 0.6%
Shell 0.6%
Python 0.5%
Other 0.3%