firmware-guide/acpi/osi.rst

1 .. SPDX-License-Identifier: GPL-2.0
22 Linux runs on two groups of machines -- those that are tested by the OEM
45 In this case, the OEM should create custom ASL to be executed by the
46 Linux kernel and changes to Linux kernel drivers to execute this custom
51 _OSI("Linux-OEM-my_interface_name")
52 where 'OEM' is needed if this is an OEM-specific hook,
54 quirk, a bug, or a bug-fix.
60 any custom Linux-* strings by default.
80 necessary to make the platform compatible with that pre-existing OS.
90 _OS "Microsoft Windows NT", though it seems somewhat far-fetched
109 For an OS-specific interface, the ACPI spec said that the BIOS and the OS
110 were to agree on a string of the form such as "Windows-interface_name".
113 not as designed, but as a direct replacement for _OS -- identifying
128 Not to be out-done, the Linux community made things worse by returning TRUE
142 of over-stating that compatibility; but the alternative has often been
163 from mid-2015 onward.  The ACPI specification will also be updated
173 answering YES to _OSI("Darwin") to enable full access
175 Just like on Windows-tested platforms, this strategy has risks.
177 Starting in Linux-3.18, the kernel answered YES to _OSI("Darwin")
183 The Linux-3.18 change in default caused power regressions on Mac
185 the default via cmdline "acpi_osi=!Darwin".  Linux-4.7 fixed
187 we hope to see Mac Thunderbolt power management support in Linux-4.11.