Commit Graph

231 Commits

Author SHA1 Message Date
Ioannis Glaropoulos 8d2b22cd05 drivers: timer: expose RTC1 ISR handler function
This commit exposes the RTC1 ISR handling function, so the
function can be directly used in tests which generate
customized vector tables manually and require a visible symbol
for the ISR function.

Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
2018-04-08 08:47:36 -04:00
Anas Nashif 788aa45888 drivers: timer: remove unkown jira ID
Remove RTOS-2676 from the comment, this is a jira issue number that was
used with zephyr in the past and not available anywhere for reference.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2018-03-26 13:13:04 -04:00
Carles Cufi f49150cab6 arch: arm: nrf: Rename nrf5 SoC Family to nrf
Upcoming Nordic ICs that share many of the peripherals and architecture
with the currently supported nRF5x ones are no longer part of the nRF5
family. In order to accomodate that, rename the SoC family from nrf5 to
nrf, so that it can contain all of the members of the wider Nordic
family.

Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
2018-03-20 11:57:14 +01:00
Holman Greenhand 400dc79326 timer: cortex_m: Fix the discontinuous readings of the cycle counter.
On a stm32, When we use the k_busy_wait function to wait a
delay (500us) just after an idle tickless period the delay could be
lower than the requested one. Consecutive readings of the cycle counter
made with the function k_cycle_get_32 juste after tickeless period
provides erroneous values (value jump) after some time (100 us).

To fix this issue we needs:

- Add the update of clock_accumulated_count value in the
_timer_idle_exit function.

- Treat the case in the get_elapsed_count function when the reload value
of the timer is set to a remaining value to wait until end of tick (see
_timer_idle_exit) . In this case the time elapsed until the systick
timer restart was not yet added to clock_accumulated_count. To retrieve
a correct cycle count we must therefore consider the number of cycle
since current tick period start and not only the cycle number since the
timer restart.

Fixes #6164

Signed-off-by: Holman Greenhand <greenhandholman@gmail.com>
2018-02-23 08:58:23 -06:00
Andy Ross 564f59060c kernel: SMP timer integration
In SMP, the system timer is used for timeslicing on auxiliary CPUs,
but the base system timekeeping via _nano_sys_clock_tick_announce() is
still done on CPU0 only (because the framework isn't prepared for
asynchronous notification yet).  Skip processing on CPU1+.

Also, due to a hardware interaction* that is difficult to work around,
timer initialization on the auxiliary CPUs is done at the very end of
the CPU bringup, just before the swap into the scheduler.  A
smp_timer_init() API has been added for this purpose.

* On ESP-32, enabling the timer seems to result in a near-synchronous
  interrupt being delivered despite my best attempts to keep it
  masked, then blowing things up because the CPU record isn't set up
  to handle it yet.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-02-16 10:44:29 -05:00
Andy Ross bba98a9c38 drivers/timer/xtensa_sys_timer: Add init/update hooks for asm2
The earlier xtensa layer put the timer initialization and update
directly into the interrupt handler, which is... weird.  Under asm2,
it's just a regular ISR and needs to do the work in the driver.

Really, this driver needs a bunch of cleanup.  The xtensa CPU timer is
two registers and one ISR: a global cycle count register, and a
compare register that will fire the IRQ when they match.  There is
*way* too much code here.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-02-16 10:44:29 -05:00
Andy Ross 39f78b9b85 drivers/timer/xtensa_sys_timer: Correctly declare ISR
The existing hand-written interrupt code is manually calling the timer
ISR, which is sort of silly and about to be replaced.  Correctly
declare the ISR with IRQ_CONNECT() so that a conventional interrupt
handling implementation can find it.  With current code this is a
noop.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-02-16 10:44:29 -05:00
Alberto Escolar Piedras 6c483ead26 native: timer bugfix in tickless mode part
Bugfix in the tickless mode part:
During _time_idle_exit it was not announcing to the kernel the
already passed silent ticks, but it was left for the tick interrupt
itself.
This did not cause any trouble so far as there was only the timer
interrupt in this board.

Signed-off-by: Alberto Escolar Piedras <alpi@oticon.com>
2018-02-08 15:56:48 -08:00
Alberto Escolar Piedras 66c1652fb8 native: native_posix timer + irq fix
Added possibility to reconfigure CONFIG_SYS_CLOCK_TICKS_PER_SEC
for the native_posix board (before it could only be 100)
+
Fixed tickless idle support
+
Minor fixes in irq wrapping

Signed-off-by: Alberto Escolar Piedras <alpi@oticon.com>
2018-02-07 16:28:16 -05:00
Jan Van Winkel ff110b4db5 timer: Corrected types in nRF system timer functions
Corrected parameter and return types  in nRF system timer functions

Signed-off-by: Jan Van Winkel <jan.van_winkel@dxplore.eu>
2018-02-02 15:28:32 +01:00
Anas Nashif 7ae749828f kconfig: fix help text indentation
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2018-01-08 08:08:45 -05:00
Anas Nashif 6b55598ad4 board: posix: add native_posix board definition
Signed-off-by: Alberto Escolar Piedras <alpi@oticon.com>
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2017-12-27 14:16:08 -05:00
Anas Nashif 429c2a4d9d kconfig: fix help syntax and add spaces
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2017-12-13 17:43:28 -06:00
Ramakrishna Pallala eb51886d8c drivers: timer: Add Altera shim driver for timer soft IP
Delete the native timer soft IP driver as we will be reusing
the Altera's HAL drivers for most of the soft IP's.

Add shim driver support for Altera timer system clock soft IP.

Signed-off-by: Ramakrishna Pallala <ramakrishna.pallala@intel.com>
2017-11-17 07:46:40 -05:00
Sebastian Bøe 0829ddfe9a kbuild: Removed KBuild
Signed-off-by: Sebastian Boe <sebastian.boe@nordicsemi.no>
2017-11-08 20:00:22 -05:00
Sebastian Bøe 12f8f76165 Introduce cmake-based rewrite of KBuild
Introducing CMake is an important step in a larger effort to make
Zephyr easy to use for application developers working on different
platforms with different development environment needs.

Simplified, this change retains Kconfig as-is, and replaces all
Makefiles with CMakeLists.txt. The DSL-like Make language that KBuild
offers is replaced by a set of CMake extentions. These extentions have
either provided simple one-to-one translations of KBuild features or
introduced new concepts that replace KBuild concepts.

This is a breaking change for existing test infrastructure and build
scripts that are maintained out-of-tree. But for FW itself, no porting
should be necessary.

For users that just want to continue their work with minimal
disruption the following should suffice:

Install CMake 3.8.2+

Port any out-of-tree Makefiles to CMake.

Learn the absolute minimum about the new command line interface:

$ cd samples/hello_world
$ mkdir build && cd build
$ cmake -DBOARD=nrf52_pca10040 ..

$ cd build
$ make

PR: zephyrproject-rtos#4692
docs: http://docs.zephyrproject.org/getting_started/getting_started.html

Signed-off-by: Sebastian Boe <sebastian.boe@nordicsemi.no>
2017-11-08 20:00:22 -05:00
Gustavo Lima Chaves 9bb07ff69a jailhouse: add support for x2APIC mode for all LOAPIC accesses
Besides the fact that we did not have that for the current supported
boards, that makes sense for this new, virtualized mode, that is meant
to be run on top of full-fledged x86 64 CPUs.

By having xAPIC mode access only, Jailhouse has to intercept those MMIO
reads and writes, in order to examine what they do and arbitrate if it's
safe or not (e.g. not all values are accepted to ICR register). This
means that we can't run away from having a VM-exit event for each and
every access to APIC memory region and this impacts the latency the
guest OS observes over bare metal a lot.

When in x2APIC mode, Jailhouse does not require VM-exits for MSR
accesses other that writes to the ICR register, so the latency the guest
observes is reduced to almost zero.

Here are some outputs of the the command line

  $ sudo ./tools/jailhouse cell stats tiny-demo

on a Jailhouse's root cell console, for one of the Zephyr demos using
LOAPIC timers, left for a couple of seconds:

Statistics for tiny-demo cell (x2APIC root, x2APIC inmate)

COUNTER                              SUM   PER SEC
vmexits_total                          7         0
vmexits_management                     3         0
vmexits_cr                             2         0
vmexits_cpuid                          1         0
vmexits_msr                            1         0
vmexits_exception                      0         0
vmexits_hypercall                      0         0
vmexits_mmio                           0         0
vmexits_pio                            0         0
vmexits_xapic                          0         0
vmexits_xsetbv                         0         0

Statistics for tiny-demo cell (xAPIC root, xAPIC inmate)

COUNTER                              SUM   PER SEC
vmexits_total                       4087        40
vmexits_xapic                       4080        40
vmexits_management                     3         0
vmexits_cr                             2         0
vmexits_cpuid                          1         0
vmexits_msr                            1         0
vmexits_exception                      0         0
vmexits_hypercall                      0         0
vmexits_mmio                           0         0
vmexits_pio                            0         0
vmexits_xsetbv                         0         0

Statistics for tiny-demo cell (xAPIC root, x2APIC inmate)

COUNTER                              SUM   PER SEC
vmexits_total                       4087        40
vmexits_msr                         4080        40
vmexits_management                     3         0
vmexits_cr                             2         0
vmexits_cpuid                          1         0
vmexits_exception                      0         0
vmexits_hypercall                      0         0
vmexits_mmio                           0         0
vmexits_pio                            0         0
vmexits_xapic                          0         0
vmexits_xsetbv                         0         0

See that under x2APIC mode on both Jailhouse/root-cell and guest, the
interruptions from the hypervisor are minimal. That is not the case when
Jailhouse is on xAPIC mode, though. Note also that, as a plus, x2APIC
accesses on the guest will map to xAPIC MMIO on the hypervisor just
fine.

Signed-off-by: Gustavo Lima Chaves <gustavo.lima.chaves@intel.com>
2017-11-07 08:58:49 -05:00
Youvedeep Singh 833025dd94 timer: xtensa_sys_timer: Tickless Kernel Implementation for Xtensa
Implement Tickless Kernel support for Xtensa Architecture.

Signed-off-by: Youvedeep Singh <youvedeep.singh@intel.com>
2017-11-07 08:17:40 -05:00
Anas Nashif 780324b8ed cleanup: rename fiber/task -> thread
We still have many places talking about tasks and threads, replace those
with thread terminology.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2017-10-30 18:41:15 -04:00
David B. Kinder 4600c37ff1 doc: Fix misspellings in header/doxygen comments
Occasional scan for misspellings missed during PR reviews

Signed-off-by: David B. Kinder <david.b.kinder@intel.com>
2017-10-17 19:40:29 -04:00
Youvedeep Singh 91063a33a4 tests: benchmark: timing_info: Add support for nrf series processors
nrf SOC uses nrf rtc timer (not sys tick), which is 32kHz,
whereas CPU runs at higher speed (nrf52 runs at 64MHz).
So 32Khz is too slow to measure critical kernel parameters.

This patch does :-
1. Add support for nrf SOC for timing_info benchmarking.
2. Uses SOC timer to measure kernel parameters.

Jira: ZEP-2314

Signed-off-by: Youvedeep Singh <youvedeep.singh@intel.com>
2017-08-31 14:25:31 -04:00
Youvedeep Singh 76b577e180 tests: benchmark: timing_info: Change API/variable Name.
The API/Variable names in timing_info looks very speicific to
platform (like systick etc), whereas these variabled are used
across platforms (nrf/arm/quark).
So this patch :-
1. changing API/Variable names to generic one.
2. Creating some of Macros whose implimentation is platform
depenent.

Jira: ZEP-2314

Signed-off-by: Youvedeep Singh <youvedeep.singh@intel.com>
2017-08-31 14:25:31 -04:00
Youvedeep Singh a4063f5362 Timer: Add TICKLESS_KERNEL support for nrf_rtc_timer.
Add support for TICKLESS KERNEL in nrf_rtc_timer for Nordic family of
processors. This patch includes :-
 1. Programming RTC based on "next timer" value from timeout queue while
     A. exiting idle_exit.
     B. on RTC interrupt.
 2. Impliments some of functions which will be required by sys_clock and
    scheduler.

ZEP-1819

Signed-off-by: Youvedeep Singh <youvedeep.singh@intel.com>
2017-08-10 13:56:24 -04:00
Youvedeep Singh 5efaca470c Timer Systick : Handle Systick timer rollback in tickless kernel Case
In Tickeless kernel Platform timekeeping is having error because
"_sys_clock_tick_count" is not getting updated correctly.
Currently "OVERFLOW" Flag (bit 16 in timer control register)
is reset before it is taken into account into _sys_clock_tick_count.

This patch sets a flag as soon as Timer Overflow occues and clears
it when time is accounted into _sys_clock_tick_count.

Jira : ZEP-2217

Signed-off-by: Youvedeep Singh <youvedeep.singh@intel.com>
2017-08-08 08:51:24 -04:00
Andrew Boie f253af2d30 drivers: timer: init earlier in boot sequence
By the time we get to POST_KERNEL, kernel services and kernel objects
should be available for use. This should include timers and the random
number generator, but we don't init the system clock until sometime
during the POST_KERNEL phase. Initialize it earlier.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2017-07-10 11:44:56 -07:00
Kumar Gala fb56b39cdd timer: xtensa_sys: Cleanup use of C99 types
We introduced some see C99 types, so convert them over to the Zephyr
types.

Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
2017-06-22 13:47:28 -04:00
Anas Nashif 397d29db42 linker: move all linker headers to include/linker
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2017-06-18 09:24:04 -05:00
Vinayak Kariappa Chettimada 707500899d drivers: timer: Fix nRF RTC timer _timer_cycle_get_32
Fix nRF RTC timer from returning more than actual cycles
in _timer_cycle_get_32, under race condition when ISR
announces to kernel.

Jira: ZEP-2229

Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>
2017-06-01 20:06:10 -04:00
Max Filippov 6a89999787 xtensa: use inline assembly instead of XT_* macros
XT_* macros are defined in xtensa HAL headers as xcc intrinsics. gcc
does not have any of these intrinsics. Replace XT_* macros with inline
assembly or provide gcc-compatible definitions.

Change-Id: If823ea8a7898a11a3a8363b17efdba27dee4c6a4
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2017-05-11 16:51:56 -04:00
Adithya Baglody d03b2496cd test: benchmarking: Timing metrics for the kernel
JIRA: ZEP-1822, ZEP-1823, ZEP-1825

Signed-off-by: Adithya Baglody <adithya.nagaraj.baglody@intel.com>
2017-05-03 08:46:30 -04:00
Ramesh Thomas b414cc56f5 timer: tickless: arcv2: Add tickless kernel support
Add tickless kernel support. Sets timer always in one
shot mode to the time the kernel scheduler needs the
next timer event. Uses mili seconds as the scheduling
time unit.

Jira: ZEP-1817
Change-Id: Ia2e63711cdd9d7d9c241b9ff08a606aa79575012
Signed-off-by: Ramesh Thomas <ramesh.thomas@intel.com>
2017-04-27 13:46:32 +00:00
Ramesh Thomas 0beffbe6be timer: tickless: cortex_m: Add tickless kernel support
Add tickless kernel support. Sets timer always in one
shot mode to the time the kernel scheduler needs the
next timer event. Uses mili seconds as the scheduling
time unit.

Jira: ZEP-1818
Change-Id: I21ce037b571c4c6ff588033a15aa49624cba7a57
Signed-off-by: Ramesh Thomas <ramesh.thomas@intel.com>
2017-04-27 13:46:31 +00:00
Ramesh Thomas 74ecc24976 timer: tickless: loapic: Add tickless kernel support
Add tickless kernel support. Sets timer always in one
shot mode to the time the kerneel scheduler needs the
next timer event. Uses mili seconds as the scheduling
time unit.

Jira: ZEP-1816
Change-Id: I85232b572759b9653c6396edc057ff4409525c97
Signed-off-by: Ramesh Thomas <ramesh.thomas@intel.com>
2017-04-27 13:46:30 +00:00
Ramesh Thomas e314ea3819 timer: tickless: hpet: Add tickless kernel support
Update the timer to use the tickless kernel interface
provided by kernel to operate in event based mode. In
this mode, the timer would not generate periodic ticks
and would only be programmed in one shot mode. It would
announce elapsed time in wall time units instead of
ticks. Timer can also be disabled enabling waiting
forever for a non-timer event.

Jira: ZEP-1812
Change-Id: I13110b9fb53b33a9244cc91a3d991f8452d330b1
Signed-off-by: Ramesh Thomas <ramesh.thomas@intel.com>
2017-04-27 13:46:29 +00:00
Ramesh Thomas 89ffd44dfb kernel: tickless: Add tickless kernel support
Adds event based scheduling logic to the kernel. Updates
management of timeouts, timers, idling etc. based on
time tracked at events rather than periodic ticks. Provides
interfaces for timers to announce and get next timer expiry
based on kernel scheduling decisions involving time slicing
of threads, timeouts and idling. Uses wall time units instead
of ticks in all scheduling activities.

The implementation involves changes in the following areas

1. Management of time in wall units like ms/us instead of ticks
The existing implementation already had an option to configure
number of ticks in a second. The new implementation builds on
top of that feature and provides option to set the size of the
scheduling granurality to mili seconds or micro seconds. This
allows most of the current implementation to be reused. Due to
this re-use and co-existence with tick based kernel, the names
of variables may contain the word "tick". However, in the
tickless kernel implementation, it represents the currently
configured time unit, which would be be mili seconds or
micro seconds. The APIs that take time as a parameter are not
impacted and they continue to pass time in mili seconds.

2. Timers would not be programmed in periodic mode
generating ticks. Instead they would be programmed in one
shot mode to generate events at the time the kernel scheduler
needs to gain control for its scheduling activities like
timers, timeouts, time slicing, idling etc.

3. The scheduler provides interfaces that the timer drivers
use to announce elapsed time and get the next time the scheduler
needs a timer event. It is possible that the scheduler may not
need another timer event, in which case the system would wait
for a non-timer event to wake it up if it is idling.

4. New APIs are defined to be implemented by timer drivers. Also
they need to handler timer events differently. These changes
have been done in the HPET timer driver. In future other timers
that support tickles kernel should implement these APIs as well.
These APIs are to re-program the timer, update and announce
elapsed time.

5. Philosopher and timer_api applications have been enabled to
test tickless kernel. Separate configuration files are created
which define the necessary CONFIG flags. Run these apps using
following command
make pristine && make BOARD=qemu_x86 CONF_FILE=prj_tickless.conf qemu

Jira: ZEP-339 ZEP-1946 ZEP-948
Change-Id: I7d950c31bf1ff929a9066fad42c2f0559a2e5983
Signed-off-by: Ramesh Thomas <ramesh.thomas@intel.com>
2017-04-27 13:46:28 +00:00
Kumar Gala cc334c7273 Convert remaining code to using newly introduced integer sized types
Convert code to use u{8,16,32,64}_t and s{8,16,32,64}_t instead of C99
integer types.  This handles the remaining includes and kernel, plus
touching up various points that we skipped because of include
dependancies.  We also convert the PRI printf formatters in the arch
code over to normal formatters.

Jira: ZEP-2051

Change-Id: Iecbb12601a3ee4ea936fd7ddea37788a645b08b0
Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
2017-04-21 11:38:23 -05:00
Kumar Gala ccad5bf3e3 drivers: convert to using newly introduced integer sized types
Convert code to use u{8,16,32,64}_t and s{8,16,32,64}_t instead of C99
integer types.

Jira: ZEP-2051

Change-Id: I08f51e2bfd475f6245771c1bd2df7ffc744c48c4
Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
2017-04-21 10:06:48 -05:00
Kumar Gala 789081673f Introduce new sized integer typedefs
This is a start to move away from the C99 {u}int{8,16,32,64}_t types to
Zephyr defined u{8,16,32,64}_t and s{8,16,32,64}_t.  This allows Zephyr
to define the sized types in a consistent manor across all the
architectures we support and not conflict with what various compilers
and libc might do with regards to the C99 types.

We introduce <zephyr/types.h> as part of this and have it include
<stdint.h> for now until we transition all the code away from the C99
types.

We go with u{8,16,32,64}_t and s{8,16,32,64}_t as there are some
existing variables defined u8 & u16 as well as to be consistent with
Zephyr naming conventions.

Jira: ZEP-2051

Change-Id: I451fed0623b029d65866622e478225dfab2c0ca8
Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
2017-04-20 16:07:08 +00:00
David B. Kinder 896cf7a00a spell: fix doxygen comment typos: /drivers
Fix doxygen comment typos used to generate API docs

Change-Id: I6fd5051c99bdcc731740c92001e525349c254d85
Signed-off-by: David B. Kinder <david.b.kinder@intel.com>
2017-04-19 10:45:34 -07:00
Anas Nashif fdd045b52b kconfig: rename non-Kconfig CONFIG_* variables
CONFIG_* usually come from Kconfig, rename variables that are locally
defined to avoid confusion about where they are set.

Change-Id: I83b8459913c5deb68dc1b9f5386b8934363a6d1f
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2017-04-11 03:14:23 +00:00
Anas Nashif b84dc2e124 kernel: remove all remaining references to nanokernel
Change-Id: I43067508898bc092879f7fe9d656ccca6fd92ab2
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2017-04-10 20:21:10 +00:00
Anas Nashif d7bc60f096 kernel: remove remaining microkernel references
Change-Id: Ie648dbaaf714316c21395bd43e555618013dbd19
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2017-04-10 20:21:05 +00:00
Jean-Paul Etienne cd14317c41 timer: riscv_machine_timer: prevent spurious interrupt while rearming the timer
Rearming the riscv machine timer is done by first updating the
mtimecmp low value register. If the low value is updated with a
relatively small value, a timer interrupt can be generated while
updating the mtimecmp high value.

To avoid such a spurious interrupt to occur, disable the timer
interrupt while rearming the timer.

Change-Id: I50ab3f19554a9a8dfe70943b6da0d20be3de88dc
Signed-off-by: Jean-Paul Etienne <fractalclone@gmail.com>
2017-04-02 15:15:03 +00:00
Jean-Paul Etienne 1451f82aeb timer: riscv_machine_timer driver depends on SOC_FAMILY_RISCV_PRIVILEGE
Change-Id: I5cbb2845979f88eb005dfd7e0b1714b6fe6167d3
Signed-off-by: Jean-Paul Etienne <fractalclone@gmail.com>
2017-04-02 15:14:59 +00:00
Ricardo Salveti 51036ca5f4 nrf_rtc_timer: clear events and counter when disabling sys_clock
Clear pending IRQ when starting and restore back the RTC1 state when
disabling sys_clock, to avoid issues when soft rebooting the device or
chainloading another Zephyr image (e.g. mcuboot).

Change-Id: I693d9168196ad2cfb8475ecfa2051eac043b1fbd
Signed-off-by: Ricardo Salveti <ricardo.salveti@linaro.org>
2017-03-27 09:05:57 -05:00
Andrew Boie b8d57738b8 cortex_m_systick: fix _timer_cycle_get_32() race
We need to account for the interrupt happening in the middle
of the calculation.

Issue: ZEP-1546
Change-Id: I193534856d7521cac7ca354d3e5b65e93b984bb1
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2017-02-22 18:45:36 +00:00
Øyvind Hovdsveen d787099c90 drivers/timer: Fixing issue in nRF RTC driver when RTC handler is blocked.
Fixes an unlikely issue that could arise if the RTC handler in the nRF RTC
driver was blocked for more than one sys tick interval. This could lead to
_sys_clock_tick_announce() being called with more than one sys tick when the
kernel did not expect it.

Jira: ZEP-1763

Change-ID: I5608fca6f0ac97a17c1ce452c1c5c67696a49a9a
Signed-off-by: Øyvind Hovdsveen <oyvind.hovdsveen@nordicsemi.no>
2017-02-22 13:58:53 +00:00
Andrew Boie 68c9d9779c x86: loapic_timer: use TSC for k_cycle_get_32()
The LOAPIC driver was doing this in a way susceptible to a very
nasty race condition: the CCR register could reset and be readable
before the associated interrupt could be delivered.

This resulted in a small window of time where CCR was reset, but
accumulated_cycle_count not updated, causing some calls to
k_cycle_get_32() to appear to jump backwards in time.

Just use the x86 TSC for these cycle timestamps. A divisor may be
provided in cases where the CPU clock speed is some multiple of
the bus speed. Modern x86 CPUs do not change their TSC rate even
when adjusting cpu frequency, so this should be a reliable timing
source.

Issue: ZEP-1546
Change-Id: I441bd8e32af866587a91f306e89e3fa0ece512b5
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2017-02-21 22:30:47 +00:00
Andrew Boie 15b8ed1a6a arcv2_timer: fix cycle count race
It's possible the timer interrupt could occur when performing the
computation, resulting in incorrect values returned.

It's still possible for bad values to be returned if the function is
called with interrupts locked, but that is only fixable with a second
timer source.

Issue: ZEP-1546
Change-Id: I16d5b04c3e32377f7249eb4fb1bf2f7c22bd0836
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2017-02-21 01:44:01 +00:00
Wojciech Bober 923560a959 drivers/timer: Rework the nRF RTC driver.
This is a reworked version of the previous RTC driver. The main
changed is related to the handling _timer_idle_exit() on non-RTC
wake-ups. The previous version didn't announce the elapsed time
to the kernel in _timer_idle_exit(). Additionally, the driver now
makes sure never to announce more idle ticks than the kernel asked
for, since the kernel does not handle negative deltas in its timeout
queues.

Change-Id: I312a357a7ce8f0c22adf5153731064b92870e47e
Signed-off-by: Wojciech Bober <wojciech.bober@nordicsemi.no>
Signed-off-by: Øyvind Hovdsveen <oyvind.hovdsveen@nordicsemi.no>
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
2017-02-17 20:27:10 +00:00