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linux/arch/sh/mm/Kconfig
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

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# SPDX-License-Identifier: GPL-2.0
menu "Memory management options"
config QUICKLIST
def_bool y
config MMU
bool "Support for memory management hardware"
depends on !CPU_SH2
default y
help
Some SH processors (such as SH-2/SH-2A) lack an MMU. In order to
boot on these systems, this option must not be set.
On other systems (such as the SH-3 and 4) where an MMU exists,
turning this off will boot the kernel on these machines with the
MMU implicitly switched off.
config PAGE_OFFSET
hex
default "0x80000000" if MMU && SUPERH32
default "0x20000000" if MMU && SUPERH64
default "0x00000000"
config FORCE_MAX_ZONEORDER
int "Maximum zone order"
range 9 64 if PAGE_SIZE_16KB
default "9" if PAGE_SIZE_16KB
range 7 64 if PAGE_SIZE_64KB
default "7" if PAGE_SIZE_64KB
range 11 64
default "14" if !MMU
default "11"
help
The kernel memory allocator divides physically contiguous memory
blocks into "zones", where each zone is a power of two number of
pages. This option selects the largest power of two that the kernel
keeps in the memory allocator. If you need to allocate very large
blocks of physically contiguous memory, then you may need to
increase this value.
This config option is actually maximum order plus one. For example,
a value of 11 means that the largest free memory block is 2^10 pages.
The page size is not necessarily 4KB. Keep this in mind when
choosing a value for this option.
config MEMORY_START
hex "Physical memory start address"
default "0x08000000"
---help---
Computers built with Hitachi SuperH processors always
map the ROM starting at address zero. But the processor
does not specify the range that RAM takes.
The physical memory (RAM) start address will be automatically
set to 08000000. Other platforms, such as the Solution Engine
boards typically map RAM at 0C000000.
Tweak this only when porting to a new machine which does not
already have a defconfig. Changing it from the known correct
value on any of the known systems will only lead to disaster.
config MEMORY_SIZE
hex "Physical memory size"
default "0x04000000"
help
This sets the default memory size assumed by your SH kernel. It can
be overridden as normal by the 'mem=' argument on the kernel command
line. If unsure, consult your board specifications or just leave it
as 0x04000000 which was the default value before this became
configurable.
# Physical addressing modes
config 29BIT
def_bool !32BIT
depends on SUPERH32
select UNCACHED_MAPPING
config 32BIT
bool
default y if CPU_SH5 || !MMU
config PMB
bool "Support 32-bit physical addressing through PMB"
depends on MMU && CPU_SH4A && !CPU_SH4AL_DSP
select 32BIT
select UNCACHED_MAPPING
help
If you say Y here, physical addressing will be extended to
32-bits through the SH-4A PMB. If this is not set, legacy
29-bit physical addressing will be used.
config X2TLB
def_bool y
depends on (CPU_SHX2 || CPU_SHX3) && MMU
config VSYSCALL
bool "Support vsyscall page"
depends on MMU && (CPU_SH3 || CPU_SH4)
default y
help
This will enable support for the kernel mapping a vDSO page
in process space, and subsequently handing down the entry point
to the libc through the ELF auxiliary vector.
From the kernel side this is used for the signal trampoline.
For systems with an MMU that can afford to give up a page,
(the default value) say Y.
config NUMA
bool "Non Uniform Memory Access (NUMA) Support"
depends on MMU && SYS_SUPPORTS_NUMA
select ARCH_WANT_NUMA_VARIABLE_LOCALITY
default n
help
Some SH systems have many various memories scattered around
the address space, each with varying latencies. This enables
support for these blocks by binding them to nodes and allowing
memory policies to be used for prioritizing and controlling
allocation behaviour.
config NODES_SHIFT
int
default "3" if CPU_SUBTYPE_SHX3
default "1"
depends on NEED_MULTIPLE_NODES
config ARCH_FLATMEM_ENABLE
def_bool y
depends on !NUMA
config ARCH_SPARSEMEM_ENABLE
def_bool y
select SPARSEMEM_STATIC
config ARCH_SPARSEMEM_DEFAULT
def_bool y
config ARCH_SELECT_MEMORY_MODEL
def_bool y
config ARCH_ENABLE_MEMORY_HOTPLUG
def_bool y
depends on SPARSEMEM && MMU
config ARCH_ENABLE_MEMORY_HOTREMOVE
def_bool y
depends on SPARSEMEM && MMU
config ARCH_MEMORY_PROBE
def_bool y
depends on MEMORY_HOTPLUG
config IOREMAP_FIXED
def_bool y
depends on X2TLB || SUPERH64
config UNCACHED_MAPPING
bool
config HAVE_SRAM_POOL
bool
select GENERIC_ALLOCATOR
choice
prompt "Kernel page size"
default PAGE_SIZE_4KB
config PAGE_SIZE_4KB
bool "4kB"
help
This is the default page size used by all SuperH CPUs.
config PAGE_SIZE_8KB
bool "8kB"
depends on !MMU || X2TLB
help
This enables 8kB pages as supported by SH-X2 and later MMUs.
config PAGE_SIZE_16KB
bool "16kB"
depends on !MMU
help
This enables 16kB pages on MMU-less SH systems.
config PAGE_SIZE_64KB
bool "64kB"
depends on !MMU || CPU_SH4 || CPU_SH5
help
This enables support for 64kB pages, possible on all SH-4
CPUs and later.
endchoice
choice
prompt "HugeTLB page size"
depends on HUGETLB_PAGE
default HUGETLB_PAGE_SIZE_1MB if PAGE_SIZE_64KB
default HUGETLB_PAGE_SIZE_64K
config HUGETLB_PAGE_SIZE_64K
bool "64kB"
depends on !PAGE_SIZE_64KB
config HUGETLB_PAGE_SIZE_256K
bool "256kB"
depends on X2TLB
config HUGETLB_PAGE_SIZE_1MB
bool "1MB"
config HUGETLB_PAGE_SIZE_4MB
bool "4MB"
depends on X2TLB
config HUGETLB_PAGE_SIZE_64MB
bool "64MB"
depends on X2TLB
config HUGETLB_PAGE_SIZE_512MB
bool "512MB"
depends on CPU_SH5
endchoice
source "mm/Kconfig"
config SCHED_MC
bool "Multi-core scheduler support"
depends on SMP
default y
help
Multi-core scheduler support improves the CPU scheduler's decision
making when dealing with multi-core CPU chips at a cost of slightly
increased overhead in some places. If unsure say N here.
endmenu
menu "Cache configuration"
config SH7705_CACHE_32KB
bool "Enable 32KB cache size for SH7705"
depends on CPU_SUBTYPE_SH7705
default y
choice
prompt "Cache mode"
default CACHE_WRITEBACK if CPU_SH2A || CPU_SH3 || CPU_SH4 || CPU_SH5
default CACHE_WRITETHROUGH if (CPU_SH2 && !CPU_SH2A)
config CACHE_WRITEBACK
bool "Write-back"
config CACHE_WRITETHROUGH
bool "Write-through"
help
Selecting this option will configure the caches in write-through
mode, as opposed to the default write-back configuration.
Since there's sill some aliasing issues on SH-4, this option will
unfortunately still require the majority of flushing functions to
be implemented to deal with aliasing.
If unsure, say N.
config CACHE_OFF
bool "Off"
endchoice
endmenu
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