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2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152Thomas Gleixner
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-27x86/i8237: Register device based on FADT legacy boot flagRajneesh Bhardwaj
From Skylake onwards, the platform controller hub (Sunrisepoint PCH) does not support legacy DMA operations to IO ports 81h-83h, 87h, 89h-8Bh, 8Fh. Currently this driver registers as syscore ops and its resume function is called on every resume from S3. On Skylake and Kabylake, this causes a resume delay of around 100ms due to port IO operations, which is a problem. This change allows to load the driver only when the platform bios explicitly supports such devices or has a cut-off date earlier than 2017 due to the following reasons: - The platforms released before year 2017 have support for the 8237. (except Sunrisepoint PCH e.g. Skylake) - Some of the BIOS that were released for platforms (Skylake, Kabylake) during 2016-17 are buggy. These BIOS do not set/unset the ACPI_FADT_LEGACY_DEVICES field in FADT table properly based on the presence or absence of the DMA device. Very recently, open source system firmware like coreboot started unsetting ACPI_FADT_LEGACY_DEVICES field in FADT table if the 8237 DMA device is not present on the PCH. Please refer to chapter 21 of 6th Generation Intel® Core™ Processor Platform Controller Hub Family: BIOS Specification. Signed-off-by: Rajneesh Bhardwaj <rajneesh.bhardwaj@intel.com> Signed-off-by: Anshuman Gupta <anshuman.gupta@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: rjw@rjwysocki.net Cc: hpa@zytor.com Cc: Alan Cox <alan@linux.intel.com> Link: https://lkml.kernel.org/r/1522336015-22994-1-git-send-email-anshuman.gupta@intel.com
2011-03-23x86: Use syscore_ops instead of sysdev classes and sysdevsRafael J. Wysocki
Some subsystems in the x86 tree need to carry out suspend/resume and shutdown operations with one CPU on-line and interrupts disabled and they define sysdev classes and sysdevs or sysdev drivers for this purpose. This leads to unnecessarily complicated code and excessive memory usage, so switch them to using struct syscore_ops objects for this purpose instead. Generally, there are three categories of subsystems that use sysdevs for implementing PM operations: (1) subsystems whose suspend/resume callbacks ignore their arguments entirely (the majority), (2) subsystems whose suspend/resume callbacks use their struct sys_device argument, but don't really need to do that, because they can be implemented differently in an arguably simpler way (io_apic.c), and (3) subsystems whose suspend/resume callbacks use their struct sys_device argument, but the value of that argument is always the same and could be ignored (microcode_core.c). In all of these cases the subsystems in question may be readily converted to using struct syscore_ops objects for power management and shutdown. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Ingo Molnar <mingo@elte.hu>
2009-02-10i8327: fix outb() parameter orderClemens Ladisch
In i8237A_resume(), when resetting the DMA controller, the parameters to dma_outb() were mixed up. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> [ cleaned up the file a tiny bit. ] Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-01-24Driver core: change sysdev classes to use dynamic kobject namesKay Sievers
All kobjects require a dynamically allocated name now. We no longer need to keep track if the name is statically assigned, we can just unconditionally free() all kobject names on cleanup. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-10-13Delete filenames in comments.Dave Jones
Since the x86 merge, lots of files that referenced their own filenames are no longer correct. Rather than keep them up to date, just delete them, as they add no real value. Additionally: - fix up comment formatting in scx200_32.c - Remove a credit from myself in setup_64.c from a time when we had no SCM - remove longwinded history from tsc_32.c which can be figured out from git. Signed-off-by: Dave Jones <davej@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-11i386: move kernelThomas Gleixner
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>