447808bf50
time_init() will set up tb_ticks_per_usec based on reality. time_init() is called *after* udbg_init_opal_common() during boot. from arch/powerpc/kernel/time.c: unsigned long tb_ticks_per_usec = 100; /* sane default */ Currently, all powernv systems have a timebase frequency of 512mhz (512000000/1000000 == 0x200) - although there's nothing written down anywhere that I can find saying that we couldn't make that different based on the requirements in the ISA. So, we've been (accidentally) thwacking the (currently) correct (for powernv at least) value for tb_ticks_per_usec earlier than we otherwise would have. The "sane default" seems to be adequate for our purposes between udbg_init_opal_common() and time_init() being called, and if it isn't, then we should probably be setting it somewhere that isn't hvc_opal.c! Signed-off-by: Stewart Smith <stewart@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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.
See Documentation/00-INDEX for a list of what is contained in each file.
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.