In current kernel, there are several places which need to check
whether there is a persistent clock for the platform. Current check
is done by calling the read_persistent_clock() and validating its
return value.
So one optimization is to do the check only once in timekeeping_init(),
and use a flag persistent_clock_exist to record it.
v2: Add a has_persistent_clock() helper function, as suggested by John.
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
The clock_adj call returns the clock state on success, which may be a
non-zero value (e.g. TIME_INS), but the modified timex data is copied
back to the user only when zero value (TIME_OK) was returned. Fix the
condition to copy the data also with positive return values.
Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
During some experiments with an external clock (in a FPGA), we saw that
the TSC clock drifted approx. 2.5ms per second.
This drift was caused by the current way of calculating the scale.
In our case cpu_khz had a value of 3292725. This resulted in a scale
value of 310. But when doing the calculation by hand it shows that the
actual value is 310.9886188491, so a value of 311 would be more precise.
With this change the value is rounded.
Signed-off-by: Bernd Faust <berndfaust@gmail.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
The purpose of this option is to allow ARM/etc systems that rely on the
class RTC subsystem to have the same kind of automatic NTP based
synchronization that we have on PC platforms. Today ARM does not
implement update_persistent_clock and makes extensive use of the class
RTC system.
When enabled CONFIG_RTC_SYSTOHC will provide a generic
rtc_update_persistent_clock that stores the current time in the RTC and
is intended complement the existing CONFIG_RTC_HCTOSYS option that loads
the RTC at boot.
Like with RTC_HCTOSYS the platform's update_persistent_clock is used
first, if it works. Platforms with mixed class RTC and non-RTC drivers
need to return ENODEV when class RTC should be used. Such an update for
PPC is included in this patch.
Long term, implementations of update_persistent_clock should migrate to
proper class RTC drivers and use CONFIG_RTC_SYSTOHC instead.
Tested on ARM kirkwood and PPC405
Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
The pstore RAM backend can get called during resume, and must be defensive
against a suspended time source. Expose getnstimeofday logic that returns
an error instead of a WARN. This can be detected and the timestamp can
be zeroed out.
Reported-by: Doug Anderson <dianders@chromium.org>
Cc: John Stultz <johnstul@us.ibm.com>
Cc: Anton Vorontsov <anton.vorontsov@linaro.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
This will make the two crucial integer divisions in the generic
ARM arch timer used for ARMv8 use the kernel DIV_ROUND_CLOSEST()
helper inline from <linux/kernel.h> so they get more precise.
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Commit f1b8274 ("clocksource: Cleanup clocksource selection") removed all
external references to clocksource_jiffies so there is no need to have the
symbol globally visible.
Fixes the following sparse warning:
CHECK kernel/time/jiffies.c kernel/time/jiffies.c:61:20: warning: symbol 'clocksource_jiffies' was not declared. Should it be static?
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: John Stultz <john.stultz@linaro.org>
I changed the strict_strtoul() to kstrtouint(). That has the check
for UINT_MAX built in to it so the ifdefs can be removed. Also
I changed a printk() to pr_info().
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Pull drm fixes (again) from Dave Airlie:
"dropped the ball on a vmware patch, so two more fixes for vmwgfx are
here, one for hibernate issue, one for a BUG trigger."
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
drm/vmwgfx: Fix a case where the code would BUG when trying to pin GMR memory
drm/vmwgfx: Fix hibernation device reset
Pull crypto fix from Herbert Xu:
"This push fixes a potential panic in cryptd which may occur with
crypto drivers such as aesni-intel."
* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
crypto: cryptd - disable softirqs in cryptd_queue_worker to prevent data corruption
Pull sound fixes from Takashi Iwai:
"Most of commits are for stable and regression fixes. Except for one
fix for a regression in 3.7-rc4, there are all driver local changes,
so nothing too much to worry."
* tag 'sound-3.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
ALSA: Fix card refcount unbalance
ALSA: hda - Add new codec ALC668 and ALC900 (default name ALC1150)
ALSA: hda - Improve HP depop when system enter to S3
ALSA: usb-audio: Fix crash at re-preparing the PCM stream
ALSA: hdspm - Fix sync check reporting on RME RayDAT
ALSA: hda - Add pin fixups for ASUS G75
ALSA: hda - Fix invalid connections in VT1802 codec
ALSA: hda - Fix empty DAC filling in patch_via.c
ALSA: hda - Force to reset IEC958 status bits for AD codecs
ALSA: es1968: Add ESS vendor ID to pm_whitelist
ALSA: HDA: Mark CS260x immutable structures const
ALSA: HDA: Fix digital microphone on CS420x
ALSA: hda: Cirrus: Fix coefficient index for beep configuration
ALSA: hda - support Teradici 2200 host card audio
ALSA: Fix typo in drivers sound
Pull pinctrl fixes from Linus Walleij:
- A set of SPEAr pinctrl fixes that recently arrived
- A fixup for the Samsung/Exynos Kconfig deps
* tag 'pinctrl-for-v3.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl:
pinctrl: samsung and exynos need to depend on OF && GPIOLIB
pinctrl: SPEAr1340: Add clcd sleep mode pin configuration
pinctrl: SPEAr1340: Make DDR reset & clock pads as gpio
pinctrl: SPEAr1310: add register entries for enabling pad direction
pinctrl: SPEAr1310: Separate out pci pins from pcie_sata pin group
pinctrl: SPEAr1310: Fix value of PERIP_CFG reigster and MCIF_SEL_SHIFT
pinctrl: SPEAr1310: fix clcd high resolution pin group name
pinctrl: SPEAr320: Correct pad mux entries for rmii/smii
pinctrl: SPEAr3xx: correct register space to configure pwm
pinctrl: SPEAr: Don't update all non muxreg bits on pinctrl_disable
Pull s390 fixes from Martin Schwidefsky:
"A couple of bug fixes. I keep the fingers crossed that we now got
transparent huge pages ready for prime time."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/cio: fix length calculation in idset.c
s390/sclp: fix addressing mode clobber
s390: Move css limits from drivers/s390/cio/ to include/asm/.
s390/thp: respect page protection in pmd_none() and pmd_present()
s390/mm: use pmd_large() instead of pmd_huge()
s390/cio: suppress 2nd path verification during resume
Pull HID fix from Jiri Kosina:
"This reverts a patch that causes regression in binding between HID
devices and drivers during device unplug/replug cycle."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid:
HID: hidraw: put old deallocation mechanism in place
Merge misc fixes from Andrew Morton:
"Five fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (5 patches)
h8300: add missing L1_CACHE_SHIFT
mm: bugfix: set current->reclaim_state to NULL while returning from kswapd()
fanotify: fix missing break
revert "epoll: support for disabling items, and a self-test app"
checkpatch: improve network block comment style checking
Pull drm fixes from Dave Airlie:
"Just radeon and nouveau, mostly regressions fixers, and a couple of
radeon register checker fixes."
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
drm/nouveau: fix acpi edid retrieval
drm/nvc0/disp: fix regression in vblank semaphore release
drm/nv40/mpeg: fix context handling
drm/nv40/graph: fix typo in type names
drm/nv41/vm: fix typo in type name
drm/radeon/si: add some missing regs to the VM reg checker
drm/radeon/cayman: add some missing regs to the VM reg checker
drm/radeon/dce3: switch back to old pll allocation order for discrete
Pull virtio and module fixes from Rusty Russell:
"YA module signing build tweak, and two cc'd to stable."
* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
virtio: Don't access index after unregister.
modules: don't break modules_install on external modules with no key.
module: fix out-by-one error in kallsyms