a60a556788
Use reference clock count based loop instead of "udelay()" for sampling of counters to improve the accuracy of re-generated CPU frequency. "udelay()" internally calls "WFE" which stops the counters and results in bigger delta between the last set freq and the re-generated value from counters. The counter sampling window used in loop is the minimum number of reference clock cycles which is known to give a stable value of CPU frequency. The change also helps to reduce the sampling window from "500us" to "<50us". Suggested-by: Antti Miettinen <amiettinen@nvidia.com> Signed-off-by: Sumit Gupta <sumitg@nvidia.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.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.