History log of /linux-master/arch/mips/dec/time.c
Revision Date Author Comments
# f06e7aa4 07-May-2018 Baolin Wang <baolin.wang@linaro.org>

MIPS: Convert update_persistent_clock() to update_persistent_clock64()

Since struct timespec is not y2038 safe on 32bit machines, this patch
converts update_persistent_clock() to update_persistent_clock64() using
struct timespec64.

The rtc_mips_set_time() and rtc_mips_set_mmss() interfaces were using
'unsigned long' type that is not y2038 safe on 32bit machines, moreover
there is only one platform implementing rtc_mips_set_time() and two
platforms implementing rtc_mips_set_mmss(), so we can just make them each
implement update_persistent_clock64() directly, to get that helper out
of the common mips code by removing rtc_mips_set_time() and
rtc_mips_set_mmss() interfaces.

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@linux-mips.org
Signed-off-by: James Hogan <jhogan@kernel.org>


# 09adad17 07-May-2018 Baolin Wang <baolin.wang@linaro.org>

MIPS: Convert read_persistent_clock() to read_persistent_clock64()

Since struct timespec is not y2038 safe on 32bit machines, this patch
converts read_persistent_clock() to read_persistent_clock64() using
struct timespec64, as well as converting mktime() to mktime64().

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@linux-mips.org
Signed-off-by: James Hogan <jhogan@kernel.org>


# b2441318 01-Nov-2017 Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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>


# daed1285 11-Sep-2013 Maciej W. Rozycki <macro@linux-mips.org>

MIPS: DECstation HRT initialization rearrangement

Not all I/O ASIC versions have the free-running counter implemented, an
early revision used in the 5000/1xx models aka 3MIN and 4MIN did not have
it. Therefore we cannot unconditionally use it as a clock source.
Fortunately if not implemented its register slot has a fixed value so it
is enough if we check for the value at the end of the calibration period
being the same as at the beginning.

This also means we need to look for another high-precision clock source on
the systems affected. The 5000/1xx can have an R4000SC processor
installed where the CP0 Count register can be used as a clock source.
Unfortunately all the R4k DECstations suffer from the missed timer
interrupt on CP0 Count reads erratum, so we cannot use the CP0 timer as a
clock source and a clock event both at a time. However we never need an
R4k clock event device because all DECstations have a DS1287A RTC chip
whose periodic interrupt can be used as a clock source.

This gives us the following four configuration possibilities for I/O ASIC
DECstations:

1. No I/O ASIC counter and no CP0 timer, e.g. R3k 5000/1xx (3MIN).

2. No I/O ASIC counter but the CP0 timer, i.e. R4k 5000/150 (4MIN).

3. The I/O ASIC counter but no CP0 timer, e.g. R3k 5000/240 (3MAX+).

4. The I/O ASIC counter and the CP0 timer, e.g. R4k 5000/260 (4MAX+).

For #1 and #2 this change stops the I/O ASIC free-running counter from
being installed as a clock source of a 0Hz frequency. For #2 it also
arranges for the CP0 timer to be used as a clock source rather than a
clock event device, because having an accurate wall clock is more
important than a high-precision interval timer. For #3 there is no
change. For #4 the change makes the I/O ASIC free-running counter
installed as a clock source so that the CP0 timer can be used as a clock
event device.

Unfortunately the use of the CP0 timer as a clock event device relies on a
succesful completion of c0_compare_interrupt. That never happens, because
while waiting for a CP0 Compare interrupt to happen the function spins in
a loop reading the CP0 Count register. This makes the CP0 Count erratum
trigger reliably causing the interrupt waited for to be lost in all cases.
As a result #4 resorts to using the CP0 timer as a clock source as well,
just as #2. However we want to keep this separate arrangement in case
(hope) c0_compare_interrupt is eventually rewritten such that it avoids
the erratum.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5825/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>


# 8533966a 04-Sep-2013 Maciej W. Rozycki <macro@linux-mips.org>

MIPS: DECstation HRT calibration bug fixes

This change corrects DECstation HRT calibration, by removing the following
bugs:

1. Calibration period selection -- HZ / 10 has been chosen, however on
DECstation computers, HZ never divides by 10, as the choice for HZ is
among 128, 256 and 1024. The choice therefore results in a systematic
calibration error, e.g. 6.25% for the usual choice of 128 for HZ:

128 / 10 * 10 = 120

(128 - 120) / 128 -> 6.25%

The change therefore makes calibration use HZ / 8 that is always
accurate for the HZ values available, getting rid of the systematic
error.

2. Calibration starting point synchronisation -- the duration of a number
of intervals between DS1287A periodic interrupt assertions is measured,
however code does not ensure at the beginning that the interrupt has
not been previously asserted. This results in a variable error of e.g.
up to another 6.25% for the period of HZ / 8 (8.(3)% with the original
HZ / 10 period) and the usual choice of 128 for HZ:

1 / 16 -> 6.25%

1 / 12 -> 8.(3)%

The change therefore adds an initial call to ds1287_timer_state that
clears any previous periodic interrupt pending.

The same issue applies to both I/O ASIC counter and R4k CP0 timer
calibration on DECstation systems as similar code is used in both cases
and both pieces of code are covered by this fix.

On an R3400 test system used this fix results in a change of the I/O ASIC
clock frequency reported from values like:

I/O ASIC clock frequency 23185830Hz

to:

I/O ASIC clock frequency 24999288Hz

removing the miscalculation by 6.25% from the systematic error and (for
the individual sample provided) a further 1.00% from the variable error,
accordingly. The nominal I/O ASIC clock frequency is 25MHz on this
system.

Here's another result, with the fix applied, from a system that has both
HRTs available (using an R4400 at 60MHz nominal):

MIPS counter frequency 59999328Hz
I/O ASIC clock frequency 24999432Hz

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5807/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>


# 3e5c1240 12-Jan-2011 Stephen Hemminger <shemminger@vyatta.com>

set_rtc_mmss: show warning message only once

Occasionally the system gets into a state where the CMOS clock has gotten
slightly ahead of current time and the periodic update of RTC fails. The
message is a nuisance and repeats spamming the log.

See: http://www.ntp.org/ntpfaq/NTP-s-trbl-spec.htm#Q-LINUX-SET-RTC-MMSS

Rather than just removing the message, make it show only once and reduce
severity since it indicates a normal and non urgent condition.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>


# d4f587c6 14-Aug-2009 Martin Schwidefsky <schwidefsky@de.ibm.com>

timekeeping: Increase granularity of read_persistent_clock()

The persistent clock of some architectures (e.g. s390) have a
better granularity than seconds. To reduce the delta between the
host clock and the guest clock in a virtualized system change the
read_persistent_clock function to return a struct timespec.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Acked-by: John Stultz <johnstul@us.ibm.com>
Cc: Daniel Walker <dwalker@fifo99.com>
LKML-Reference: <20090814134811.013873340@de.ibm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>


# 49316cbf0 06-Jul-2009 Ralf Baechle <ralf@linux-mips.org>

MIPS: Eleminate filenames from comments

They tend to get not updated when files are moved around or copied and
lack any obvious use. While at it zap some only too obvious comments and
as per Shinya's suggestion, add a copyright header to extable.c.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Acked-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Acked-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>


# 02112dbc 18-Oct-2008 Adrian Bunk <bunk@kernel.org>

mips: use bcd2bin/bin2bcd

Changes mips to use the new bcd2bin/bin2bcd functions instead of the
obsolete BCD_TO_BIN/BIN_TO_BCD/BCD2BIN/BIN2BCD macros.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>


# 6457d9fc 24-Apr-2008 Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>

[MIPS] DS1287: Add clockevent driver

Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>


# 4247417d 23-Apr-2008 Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>

[MIPS] add DECstation I/O ASIC clocksource

Add DECstation I/O ASIC clocksource

Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>


# c9662341 09-Dec-2007 Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>

[MIPS] time: remove unused mips_timer_state()

Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>


# 4b550488 11-Oct-2007 Ralf Baechle <ralf@linux-mips.org>

[MIPS] Deforest the function pointer jungle in the time code.

Hard to follow who is pointing what to where and why so it's simply getting
in the way of the time code renovation.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>


# 99977c1e 24-Sep-2007 Maciej W. Rozycki <macro@linux-mips.org>

[MIPS] dec/time.c: Remove no longer needed inclusion of <asm/div64.h>.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>


# 00598560 11-Nov-2006 Atsushi Nemoto <anemo@mba.ocn.ne.jp>

[MIPS] mips HPT cleanup: make clocksource_mips public

Make clocksource_mips public and get rid of mips_hpt_read,
mips_hpt_mask.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>


# 16b7b2ac 23-Oct-2006 Atsushi Nemoto <anemo@mba.ocn.ne.jp>

[MIPS] Fixup migration to GENERIC_TIME

Since we already moved to GENERIC_TIME, we should implement alternatives
of old do_gettimeoffset routines to get sub-jiffies resolution from
gettimeofday(). This patch includes:

* MIPS clocksource support (based on works by Manish Lachwani).
* remove unused gettimeoffset routines and related codes.
* remove unised 64bit do_div64_32().
* simplify mips_hpt_init. (no argument needed, __init tag)
* simplify c0_hpt_timer_init. (no need to write to c0_count)
* remove some hpt_init routines.
* mips_hpt_mask variable to specify bitmask of hpt value.
* convert jmr3927_do_gettimeoffset to jmr3927_hpt_read.
* convert ip27_do_gettimeoffset to ip27_hpt_read.
* convert bcm1480_do_gettimeoffset to bcm1480_hpt_read.
* simplify sb1250 hpt functions. (no need to subtract and shift)

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>


# 8db02010 02-Oct-2006 Ralf Baechle <ralf@linux-mips.org>

[MIPS] Fix wreckage after removal of tickadj; convert to GENERIC_TIME.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>


# 54d0a216 09-Jul-2006 Ralf Baechle <ralf@linux-mips.org>

[MIPS] Replace board_timer_setup function pointer by plat_timer_setup.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

---


# 1723b4a3 19-Jun-2006 Atsushi Nemoto <anemo@mba.ocn.ne.jp>

[MIPS] Make timer interrupt frequency configurable from kconfig.

Make HZ configurable. DECSTATION can select 128/256/1024 HZ, JAZZ can
only select 100 HZ, others can select 100/128/250/256/1000/1024 HZ if
not explicitly specified). Also remove all mach-xxx/param.h files and
update all defconfigs according to current HZ value.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>


# ddcabb4f 28-Mar-2006 Matt Mackall <mpm@selenic.com>

[PATCH] RTC: Remove RTC UIP synchronization on MIPS-based DEC

Move real_year inside the read loop and move the spinlock up as well

Signed-off-by: Matt Mackall <mpm@selenic.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>


# d23ee8fe 27-Mar-2006 Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>

[PATCH] mips: fixed collision of rtc function name

Fix the collision of rtc function name.

Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>


# 53c2df2f 02-Nov-2005 Atsushi Nemoto <anemo@mba.ocn.ne.jp>

Use rtc_lock to protect RTC operations

Many RTC routines were not protected against each other, so there are
potential races, for example, ntp-update against /dev/rtc. This patch
fixes them using rtc_lock.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>


# 1da177e4 16-Apr-2005 Linus Torvalds <torvalds@ppc970.osdl.org>

Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!