b782e8d07b
Currently we're using "sbfx" to extract the PMUVer from ID_AA64DFR0_EL1 and skip the init/reset if no PMU present when the extracted PMUVer is negative or is zero. However for PMUv3p8 the PMUVer will be 0b1000 and PMUVer extracted by "sbfx" will always be negative and we'll skip the init/reset in __init_el2_debug/reset_pmuserenr_el0 unexpectedly. So this patch use "ubfx" instead of "sbfx" to extract the PMUVer. If the PMUVer is implementation defined (0b1111) or not implemented(0b0000) then skip the reset/init. Previously we'll also skip the init/reset if the PMUVer is higher than the version we known (currently PMUv3p9), with this patch we'll only skip if the PMU is not implemented or implementation defined. This keeps consistence with how we probe the PMU in the driver with pmuv3_implemented(). Signed-off-by: Yicong Yang <yangyicong@hisilicon.com> Link: https://lore.kernel.org/r/20240411123030.7201-1-yangyicong@huawei.com Signed-off-by: Will Deacon <will@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 reStructuredText 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.