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Set the capacity-dmips-mhz for R-Car Gen3 SoCs, that is based on dhrystone. The average in 10 times of dhrystone result as follows: r8a7795 SoC (A57x4 + A53x4) CPU max-freq dhrystone --------------------------------- A57 1500 MHz 11470943 lps/s A53 1200 MHz 4798583 lps/s r8a7796 SoC (A57x2 + A53x4) CPU max-freq dhrystone --------------------------------- A57 1500 MHz 11463526 lps/s A53 1200 MHz 4793276 lps/s Based on above, capacity-dmips-mhz values are calculated as follows: r8a7795 SoC A57 : 1024 / (11470943 / 1500) * (11470943 / 1500) = 1024 A53 : 1024 / (11470943 / 1500) * ( 4798583 / 1200) = 535 r8a7796 SoC A57 : 1024 / (11463526 / 1500) * (11463526 / 1500) = 1024 A53 : 1024 / (11463526 / 1500) * ( 4793276 / 1200) = 535 However, since each CPUs have different max frequencies, the final CPU capacities of A53 are scaled by this difference, the values are as follows. [r8a7795 SoC] $ cat /sys/devices/system/cpu/cpu*/cpu_capacity 1024 <---- CPU capacity of A57 1024 1024 1024 428 <---- CPU capacity of A53 428 428 428 [r8a7796 SoC] $ cat /sys/devices/system/cpu/cpu*/cpu_capacity 1024 <---- CPU capacity of A57 1024 428 <---- CPU capacity of A53 428 428 428 Signed-off-by: Gaku Inami <gaku.inami.xh@renesas.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Simon Horman <horms+renesas@verge.net.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.
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.