summaryrefslogtreecommitdiff
path: root/drivers/clocksource/arc_timer.c
AgeCommit message (Collapse)AuthorFilesLines
2019-07-03Merge branch 'timers/vdso' into timers/coreThomas Gleixner1-4/+1
so the hyper-v clocksource update can be applied.
2019-06-25clocksource/drivers/arc_timer: Use BIT() instead of _BITUL()Masahiro Yamada1-1/+2
This is in-kernel C code, so there is no reason to use _BITUL(). Replace it with equivalent BIT(). I added #include <linux/bits.h> explicitly although it has been included by other headers eventually. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500Thomas Gleixner1-4/+1
Based on 2 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 version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-19clocksource/drivers/arc_timer: Utilize generic sched_clockAlexey Brodkin1-0/+22
It turned out we used to use default implementation of sched_clock() from kernel/sched/clock.c which was as precise as 1/HZ, i.e. by default we had 10 msec granularity of time measurement. Now given ARC built-in timers are clocked with the same frequency as CPU cores we may get much higher precision of time tracking. Thus we switch to generic sched_clock which really reads ARC hardware counters. This is especially helpful for measuring short events. That's what we used to have: ------------------------------>8------------------------ $ perf stat /bin/sh -c /root/lmbench-master/bin/arc/hello > /dev/null Performance counter stats for '/bin/sh -c /root/lmbench-master/bin/arc/hello': 10.000000 task-clock (msec) # 2.832 CPUs utilized 1 context-switches # 0.100 K/sec 1 cpu-migrations # 0.100 K/sec 63 page-faults # 0.006 M/sec 3049480 cycles # 0.305 GHz 1091259 instructions # 0.36 insn per cycle 256828 branches # 25.683 M/sec 27026 branch-misses # 10.52% of all branches 0.003530687 seconds time elapsed 0.000000000 seconds user 0.010000000 seconds sys ------------------------------>8------------------------ And now we'll see: ------------------------------>8------------------------ $ perf stat /bin/sh -c /root/lmbench-master/bin/arc/hello > /dev/null Performance counter stats for '/bin/sh -c /root/lmbench-master/bin/arc/hello': 3.004322 task-clock (msec) # 0.865 CPUs utilized 1 context-switches # 0.333 K/sec 1 cpu-migrations # 0.333 K/sec 63 page-faults # 0.021 M/sec 2986734 cycles # 0.994 GHz 1087466 instructions # 0.36 insn per cycle 255209 branches # 84.947 M/sec 26002 branch-misses # 10.19% of all branches 0.003474829 seconds time elapsed 0.003519000 seconds user 0.000000000 seconds sys ------------------------------>8------------------------ Note how much more meaningful is the second output - time spent for execution pretty much matches number of cycles spent (we're runnign @ 1GHz here). Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Acked-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2018-05-18clocksource/drivers/arc_timer: Add comments about locking while read GFRCEugeniy Paltsev1-0/+14
This came to light in some internal discussions and it is nice to have this documented rather than digging up the PRM (Prog Ref Manual) again. Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com> Acked-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2018-02-28clocksource/drivers/arc_timer: Update some commentsVineet Gupta1-3/+8
TIMER0 interrupt ACK is different for ARC700 and HS3x cores. This came to light in some internal discussions and it is nice to have this documented rather than digging up the PRM (Programmers Reference Manual). Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Vineet Gupta <Vineet.Gupta1@synopsys.com> Cc: linux-snps-arc@lists.infradead.org Link: https://lkml.kernel.org/r/1519241491-12570-1-git-send-email-vgupta@synopsys.com
2017-06-14clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLAREDaniel Lezcano1-3/+3
The CLOCKSOURCE_OF_DECLARE macro is used widely for the timers to declare the clocksource at early stage. However, this macro is also used to initialize the clockevent if any, or the clockevent only. It was originally suggested to declare another macro to initialize a clockevent, so in order to separate the two entities even they belong to the same IP. This was not accepted because of the impact on the DT where splitting a clocksource/clockevent definition does not make sense as it is a Linux concept not a hardware description. On the other side, the clocksource has not interrupt declared while the clockevent has, so it is easy from the driver to know if the description is for a clockevent or a clocksource, IOW it could be implemented at the driver level. So instead of dealing with a named clocksource macro, let's use a more generic one: TIMER_OF_DECLARE. The patch has not functional changes. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Heiko Stuebner <heiko@sntech.de> Acked-by: Neil Armstrong <narmstrong@baylibre.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Matthias Brugger <matthias.bgg@gmail.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
2017-04-07clocksource: Add missing line break to error messagesRafał Miłecki1-7/+7
Printing with pr_* functions requires adding line break manually. Signed-off-by: Rafał Miłecki <rafal@milecki.pl> Acked-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2016-12-26Merge branch 'timers-urgent-for-linus' of ↵Linus Torvalds1-6/+6
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer type cleanups from Thomas Gleixner: "This series does a tree wide cleanup of types related to timers/timekeeping. - Get rid of cycles_t and use a plain u64. The type is not really helpful and caused more confusion than clarity - Get rid of the ktime union. The union has become useless as we use the scalar nanoseconds storage unconditionally now. The 32bit timespec alike storage got removed due to the Y2038 limitations some time ago. That leaves the odd union access around for no reason. Clean it up. Both changes have been done with coccinelle and a small amount of manual mopping up" * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: ktime: Get rid of ktime_equal() ktime: Cleanup ktime_set() usage ktime: Get rid of the union clocksource: Use a plain u64 instead of cycle_t
2016-12-25clocksource: Use a plain u64 instead of cycle_tThomas Gleixner1-6/+6
There is no point in having an extra type for extra confusion. u64 is unambiguous. Conversion was done with the following coccinelle script: @rem@ @@ -typedef u64 cycle_t; @fix@ typedef cycle_t; @@ -cycle_t +u64 Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org>
2016-12-25cpu/hotplug: Cleanup state namesThomas Gleixner1-1/+1
When the state names got added a script was used to add the extra argument to the calls. The script basically converted the state constant to a string, but the cleanup to convert these strings into meaningful ones did not happen. Replace all the useless strings with 'subsys/xxx/yyy:state' strings which are used in all the other places already. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sebastian Siewior <bigeasy@linutronix.de> Link: http://lkml.kernel.org/r/20161221192112.085444152@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-30clocksource: import ARC timer driverVineet Gupta1-0/+336
This adds support for - CONFIG_ARC_TIMERS : legacy 32-bit TIMER0 and TIMER1 which count UP from @CNT to @LIMIT, before optionally triggering an interrupt. These are programmed using ARC auxiliary register interface. These are present in all ARC cores (ARC700 and ARC HS38) TIMER0 serves as clockevent for all ARC linux builds. TIMER1 is used for clocksource in arc700 builds. - CONFIG_ARC_TIMERS_64BIT: 64-bit counters, RTC and GFRC found in ARC HS38 cores. These are independnet IP blocks with different programming model respectively. Link: http://lkml.kernel.org/r/20161111231132.GA4186@mai Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>