71119b54a2
Support Z and Z2 clocks with parent frequencies greater than UINT32_MAX Hz (~4.29GHz). The DIV_ROUND_CLOSEST_ULL() macro accepts a 64bit dividend and 32bit divisor. This leads to truncation of the divisor, which is the Z or Z2 parent clock frequency in HZ, on platforms where frequency of that clock is greater than UINT32_MAX Hz. To resolve this problem the DIV64_U64_ROUND_CLOSEST() macro, which takes on an unsigned 64bit dividend and divisor, is used. An earlier version of this patch made use of the existing DIV_ROUND_CLOSEST() macro, which accepts the prevailing type of the dividend and divisor. However, this does not compile on 32bit systems, such as i386 and mips, when called with the types used at this call site, an unsigned long long dividend and unsigned long divisor. This work is in preparation for supporting the Z2 clock on the R-Car Gen3 E3 (r8a77990) SoC which has a 4.8GHz parent clock. Signed-off-by: Simon Horman <horms+renesas@verge.net.au> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
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.