b1a9585cc3
One of the requirement for modern x86 system to enter lowest power mode (SLP_S0) is SATA IP block to be off. This is true even during when platform is suspended to idle and not only in opportunistic (runtime) suspend. Several of these system don't have traditional ACPI S3, so it is important that they enter SLP_S0 state, to avoid draining battery even during suspend. So it is important that out of the box Linux installation reach this state. SATA IP block doesn't get turned off till SATA is in DEVSLP mode. Here user has to either use scsi-host sysfs or tools like powertop to set the sata-host link_power_management_policy to min_power. This change sets by default link power management policy to min_power with partial (preferred) or slumber support on idle for some platforms. To avoid regressions, the following conditions are used: - User didn't override the policy from module parameter - The kernel config is already set to use med_power_with_dipm or deeper - System is a SLP_S0 capable using ACPI low power idle flag This combination will make sure that systems are fairly recent and since getting shipped with SLP_S0 support, the DEVSLP function is already validated. Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org> |
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| Documentation | ||
| LICENSES | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| firmware | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
README
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.
See Documentation/00-INDEX for a list of what is contained in each file.
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.