cc75549548
Currently for each timestamp frame, the SW needs to go and read the received timestamp over the MDIO bus. But the HW has the capability to store the received nanoseconds part and the least significant two bits of the seconds in the reserved field of the PTP header. In this way we could save few MDIO transactions (actually a little more transactions because the access to the PTP registers are indirect) for each received frame. Instead of reading the rest of seconds part of the timestamp of the frame using MDIO transactions schedule PTP worker thread to read the seconds part every 500ms and then for each of the received frames use this information. Because if for example running with 512 frames per second, there is no point to read 512 times the second part. Doing all these changes will give a great CPU usage performance. Running ptp4l with logSyncInterval of -9 will give a ~60% CPU improvement. Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com> Acked-by: Richard Cochran <richardcochran@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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.