kernel_optimize_test/arch/arm/mach-omap2/omap-pm.h
Greg Kroah-Hartman b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00

162 lines
5.9 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* omap-pm.h - OMAP power management interface
*
* Copyright (C) 2008-2010 Texas Instruments, Inc.
* Copyright (C) 2008-2010 Nokia Corporation
* Paul Walmsley
*
* Interface developed by (in alphabetical order): Karthik Dasu, Jouni
* Högander, Tony Lindgren, Rajendra Nayak, Sakari Poussa,
* Veeramanikandan Raju, Anand Sawant, Igor Stoppa, Paul Walmsley,
* Richard Woodruff
*/
#ifndef ASM_ARM_ARCH_OMAP_OMAP_PM_H
#define ASM_ARM_ARCH_OMAP_OMAP_PM_H
#include <linux/device.h>
#include <linux/cpufreq.h>
#include <linux/clk.h>
#include <linux/pm_opp.h>
/*
* agent_id values for use with omap_pm_set_min_bus_tput():
*
* OCP_INITIATOR_AGENT is only valid for devices that can act as
* initiators -- it represents the device's L3 interconnect
* connection. OCP_TARGET_AGENT represents the device's L4
* interconnect connection.
*/
#define OCP_TARGET_AGENT 1
#define OCP_INITIATOR_AGENT 2
/**
* omap_pm_if_early_init - OMAP PM init code called before clock fw init
* @mpu_opp_table: array ptr to struct omap_opp for MPU
* @dsp_opp_table: array ptr to struct omap_opp for DSP
* @l3_opp_table : array ptr to struct omap_opp for CORE
*
* Initialize anything that must be configured before the clock
* framework starts. The "_if_" is to avoid name collisions with the
* PM idle-loop code.
*/
int __init omap_pm_if_early_init(void);
/**
* omap_pm_if_init - OMAP PM init code called after clock fw init
*
* The main initialization code. OPP tables are passed in here. The
* "_if_" is to avoid name collisions with the PM idle-loop code.
*/
int __init omap_pm_if_init(void);
/*
* Device-driver-originated constraints (via board-*.c files, platform_data)
*/
/**
* omap_pm_set_max_mpu_wakeup_lat - set the maximum MPU wakeup latency
* @dev: struct device * requesting the constraint
* @t: maximum MPU wakeup latency in microseconds
*
* Request that the maximum interrupt latency for the MPU to be no
* greater than @t microseconds. "Interrupt latency" in this case is
* defined as the elapsed time from the occurrence of a hardware or
* timer interrupt to the time when the device driver's interrupt
* service routine has been entered by the MPU.
*
* It is intended that underlying PM code will use this information to
* determine what power state to put the MPU powerdomain into, and
* possibly the CORE powerdomain as well, since interrupt handling
* code currently runs from SDRAM. Advanced PM or board*.c code may
* also configure interrupt controller priorities, OCP bus priorities,
* CPU speed(s), etc.
*
* This function will not affect device wakeup latency, e.g., time
* elapsed from when a device driver enables a hardware device with
* clk_enable(), to when the device is ready for register access or
* other use. To control this device wakeup latency, use
* omap_pm_set_max_dev_wakeup_lat()
*
* Multiple calls to omap_pm_set_max_mpu_wakeup_lat() will replace the
* previous t value. To remove the latency target for the MPU, call
* with t = -1.
*
* XXX This constraint will be deprecated soon in favor of the more
* general omap_pm_set_max_dev_wakeup_lat()
*
* Returns -EINVAL for an invalid argument, -ERANGE if the constraint
* is not satisfiable, or 0 upon success.
*/
int omap_pm_set_max_mpu_wakeup_lat(struct device *dev, long t);
/**
* omap_pm_set_min_bus_tput - set minimum bus throughput needed by device
* @dev: struct device * requesting the constraint
* @tbus_id: interconnect to operate on (OCP_{INITIATOR,TARGET}_AGENT)
* @r: minimum throughput (in KiB/s)
*
* Request that the minimum data throughput on the OCP interconnect
* attached to device @dev interconnect agent @tbus_id be no less
* than @r KiB/s.
*
* It is expected that the OMAP PM or bus code will use this
* information to set the interconnect clock to run at the lowest
* possible speed that satisfies all current system users. The PM or
* bus code will adjust the estimate based on its model of the bus, so
* device driver authors should attempt to specify an accurate
* quantity for their device use case, and let the PM or bus code
* overestimate the numbers as necessary to handle request/response
* latency, other competing users on the system, etc. On OMAP2/3, if
* a driver requests a minimum L4 interconnect speed constraint, the
* code will also need to add an minimum L3 interconnect speed
* constraint,
*
* Multiple calls to omap_pm_set_min_bus_tput() will replace the
* previous rate value for this device. To remove the interconnect
* throughput restriction for this device, call with r = 0.
*
* Returns -EINVAL for an invalid argument, -ERANGE if the constraint
* is not satisfiable, or 0 upon success.
*/
int omap_pm_set_min_bus_tput(struct device *dev, u8 agent_id, unsigned long r);
/*
* CPUFreq-originated constraint
*
* In the future, this should be handled by custom OPP clocktype
* functions.
*/
/*
* Device context loss tracking
*/
/**
* omap_pm_get_dev_context_loss_count - return count of times dev has lost ctx
* @dev: struct device *
*
* This function returns the number of times that the device @dev has
* lost its internal context. This generally occurs on a powerdomain
* transition to OFF. Drivers use this as an optimization to avoid restoring
* context if the device hasn't lost it. To use, drivers should initially
* call this in their context save functions and store the result. Early in
* the driver's context restore function, the driver should call this function
* again, and compare the result to the stored counter. If they differ, the
* driver must restore device context. If the number of context losses
* exceeds the maximum positive integer, the function will wrap to 0 and
* continue counting. Returns the number of context losses for this device,
* or negative value upon error.
*/
int omap_pm_get_dev_context_loss_count(struct device *dev);
void omap_pm_enable_off_mode(void);
void omap_pm_disable_off_mode(void);
#endif