cf488dcd0a
We guard the suspend entry code from running unless we have proper BIOS support for either S3 mode or s0ix mode. If a user's system doesn't support either of these modes the kernel still does offer s2idle in `/sys/power/mem_sleep` so there is an expectation from users that it works even if the power consumption remains very high. Rafael Ávila de Espíndola reports that a system of his has a non-functional graphics stack after resuming. That system doesn't support S3 and the FADT doesn't indicate support for low power idle. Through some experimentation it was concluded that even without the hardware s0i3 support provided by the amd_pmc driver the power consumption over suspend is decreased by running amdgpu's s0ix suspend routine. The numbers over suspend showed: * No patch: 9.2W * Skip amdgpu suspend entirely: 10.5W * Run amdgpu s0ix routine: 7.7W As this does improve the power, remove some of the guard rails in `amdgpu_acpi.c` for only running s0ix suspend routines in the right circumstances. However if this turns out to cause regressions for anyone, we should revert this change and instead opt for skipping suspend/resume routines entirely or try to fix the underlying behavior that makes graphics fail after resume without underlying platform support. Reported-by: Rafael Ávila de Espíndola <rafael@espindo.la> Link: https://gitlab.freedesktop.org/drm/amd/-/issues/2364 Acked-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
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.