28850b8043
[ Upstream commit 4daca379c703ff55edc065e8e5173dcfeecf0148 ] The MSR_TURBO_RATIO_LIMIT can be 0. This is not an error. User can update this MSR via BIOS settings on some systems or can use msr tools to update. Also some systems boot with value = 0. This results in display of cpufreq/cpuinfo_max_freq wrong. This value will be equal to cpufreq/base_frequency, even though turbo is enabled. But platform will still function normally in HWP mode as we get max 1-core frequency from the MSR_HWP_CAPABILITIES. This MSR is already used to calculate cpu->pstate.turbo_freq, which is used for to set policy->cpuinfo.max_freq. But some other places cpu->pstate.turbo_pstate is used. For example to set policy->max. To fix this, also update cpu->pstate.turbo_pstate when updating cpu->pstate.turbo_freq. Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.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.