Unfortunately, the architecture provides no means to determine the bit
width of the system counter. However, we do know the following from the
specification:
- the system counter is at least 56 bits wide
- Roll-over time of not less than 40 years
To date, the arch timer driver has depended on the first property,
assuming any system counter to be 56 bits wide and masking off the rest.
However, combining a narrow clocksource mask with a high frequency
counter could result in prematurely wrapping the system counter by a
significant margin. For example, a 56 bit wide, 1GHz system counter
would wrap in a mere 2.28 years!
This is a problem for two reasons: v8.6+ implementations are required to
provide a 64 bit, 1GHz system counter. Furthermore, before v8.6,
implementers may select a counter frequency of their choosing.
Fix the issue by deriving a valid clock mask based on the second
property from above. Set the floor at 56 bits, since we know no system
counter is narrower than that.
[maz: fixed width computation not to lose the last bit, added
max delta generation for the timer]
Suggested-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Oliver Upton <oupton@google.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210807191428.3488948-1-oupton@google.com
Link: https://lore.kernel.org/r/20211017124225.3018098-13-maz@kernel.org
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: hongrongxuan <hongrongxuan@huawei.com>
TVAL usage is now long gone, get rid of the leftovers.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211017124225.3018098-11-maz@kernel.org
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: hongrongxuan <hongrongxuan@huawei.com>
The Applied Micro XGene-1 SoC has a busted implementation of the
CVAL register: it looks like it is based on TVAL instead of the
other way around. The net effect of this implementation blunder
is that the maximum deadline you can program in the timer is
32bit wide.
Use a MIDR check to notice the broken CPU, and reduce the width
of the timer to 32bit.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211017124225.3018098-10-maz@kernel.org
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: hongrongxuan <hongrongxuan@huawei.com>
Proudly tell the code code that we have a timer able to handle
56 bits deltas.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211017124225.3018098-9-maz@kernel.org
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: hongrongxuan <hongrongxuan@huawei.com>
Similarily to the sysreg-based timer, move the MMIO over to using
the CVAL registers instead of TVAL. Note that there is no warranty
that the 64bit MMIO access will be atomic, but the timer is always
disabled at the point where we program CVAL.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211017124225.3018098-8-maz@kernel.org
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: hongrongxuan <hongrongxuan@huawei.com>
The MMIO timer base address gets published after we have registered
the callbacks and the interrupt handler, which is... a bit dangerous.
Fix this by moving the base address publication to the point where
we register the timer, and expose a pointer to the timer structure
itself rather than a naked value.
Reviewed-by: Oliver Upton <oupton@google.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211017124225.3018098-7-maz@kernel.org
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: hongrongxuan <hongrongxuan@huawei.com>
Conflicts:
drivers/clocksource/arm_arch_timer.c
The '_tval' name in the erratum handling function names doesn't
make much sense anymore (and they were using CVAL the first place).
Drop the _tval tag.
Reviewed-by: Oliver Upton <oupton@google.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211017124225.3018098-6-maz@kernel.org
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: hongrongxuan <hongrongxuan@huawei.com>
In order to cope better with high frequency counters, move the
programming of the timers from the countdown timer (TVAL) over
to the comparator (CVAL).
The programming model is slightly different, as we now need to
read the current counter value to have an absolute deadline
instead of a relative one.
There is a small overhead to this change, which we will address
in the following patches.
Reviewed-by: Oliver Upton <oupton@google.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211017124225.3018098-5-maz@kernel.org
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: hongrongxuan <hongrongxuan@huawei.com>
The various accessors for the timer sysreg and MMIO registers are
currently hardwired to 32bit. However, we are about to introduce
the use of the CVAL registers, which require a 64bit access.
Upgrade the write side of the accessors to take a 64bit value
(the read side is left untouched as we don't plan to ever read
back any of these registers).
No functional change expected.
Reviewed-by: Oliver Upton <oupton@google.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211017124225.3018098-4-maz@kernel.org
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: hongrongxuan <hongrongxuan@huawei.com>
The arch timer driver never reads the various TVAL registers, only
writes to them. It is thus pointless to provide accessors
for them and to implement errata workarounds.
Drop these read-side accessors, and add a couple of BUG() statements
for the time being. These statements will be removed further down
the line.
Reviewed-by: Oliver Upton <oupton@google.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211017124225.3018098-3-maz@kernel.org
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: hongrongxuan <hongrongxuan@huawei.com>
As we are about to change the registers that are used by the driver,
start by adding build-time checks to ensure that we always handle
all registers and access modes.
Suggested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211017124225.3018098-2-maz@kernel.org
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: hongrongxuan <hongrongxuan@huawei.com>
This reverts commit 5de2e163fc7488991029a2f44283c43034863b6d.
On AmpereOne cpu, the ping latency will reach 1s. so revert it.
Signed-off-by: Huang Cun <cunhuang@tencent.com>
Sync code to the same with tk4 pub/lts/0017-kabi, except deleted rue
and wujing. Partners can submit pull requests to this branch, and we
can pick the commits to tk4 pub/lts/0017-kabi easly.
Signed-off-by: Jianping Liu <frankjpliu@tencent.com>
Gitee limit the repo's size to 3GB, to reduce the size of the code,
sync codes to ock 5.4.119-20.0009.21 in one commit.
Signed-off-by: Jianping Liu <frankjpliu@tencent.com>
Sync kernel codes to the same with 590eaf1fec ("Init Repo base on
linux 5.4.32 long term, and add base tlinux kernel interfaces."), which
is from tk4, and it is the base of tk4.
Signed-off-by: Jianping Liu <frankjpliu@tencent.com>
function (Geert Uytterhoeven)
- Fix double free when using timer-of in the mediatek timer driver
(Fabien Parent)
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Merge tag 'timers-v5.4-rc6' of https://git.linaro.org/people/daniel.lezcano/linux into timers/urgent
Pull clockevent fixes from Daniel Lezcano:
- Fix scary messages in sh_mtu2 by using platform_irq_count() helper
function (Geert Uytterhoeven)
- Fix double free when using timer-of in the mediatek timer driver
(Fabien Parent)
As platform_get_irq_by_name() now prints an error when the interrupt
does not exist, looping over possibly non-existing interrupts causes the
printing of scary messages like:
sh_mtu2 fcff0000.timer: IRQ tgi1a not found
sh_mtu2 fcff0000.timer: IRQ tgi2a not found
Fix this by using the platform_irq_count() helper, to avoid touching
non-existent interrupts. Limit the returned number of interrupts to the
maximum number of channels currently supported by the driver in a
future-proof way, i.e. using ARRAY_SIZE() instead of a hardcoded number.
Fixes: 7723f4c5ec ("driver core: platform: Add an error message to platform_get_irq*()")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20191016143003.28561-1-geert+renesas@glider.be
Randy Dunlap reports on the sparse list that sparse warns about this
expression:
of_irq->percpu ? free_percpu_irq(of_irq->irq, clkevt) :
free_irq(of_irq->irq, clkevt);
and honestly, sparse is correct to warn. The return type of
free_percpu_irq() is 'void', while free_irq() returns a 'const void *'
that is the devname argument passed in to the request_irq().
You can't mix a void type with a non-void types in a conditional
expression according to the C standard. It so happens that gcc seems to
accept it - and the resulting type of the expression is void - but
there's really no reason for the kernel to have this kind of
non-standard expression with no real upside.
The natural way to write that expression is with an if-statement:
if (of_irq->percpu)
free_percpu_irq(of_irq->irq, clkevt);
else
free_irq(of_irq->irq, clkevt);
which is more legible anyway.
I'm not sure why that timer-of code seems to have this odd pattern. It
does the same at allocation time, but at least there the types match,
and it makes sense as an expression.
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- boot_mem_map is removed, providing a nice cleanup made possible by the
recent removal of bootmem.
- Some fixes to atomics, in general providing compiler barriers for
smp_mb__{before,after}_atomic plus fixes specific to Loongson CPUs or
MIPS32 systems using cmpxchg64().
- Conversion to the new generic VDSO infrastructure courtesy of Vincenzo
Frascino.
- Removal of undefined behavior in set_io_port_base(), fixing the
behavior of some MIPS kernel configurations when built with recent
clang versions.
- Initial MIPS32 huge page support, functional on at least Ingenic SoCs.
- pte_special() is now supported for some configurations, allowing among
other things generic fast GUP to be used.
- Miscellaneous fixes & cleanups.
And platform specific changes:
- Major improvements to Ingenic SoC support from Paul Cercueil, mostly
enabled by the inclusion of the new TCU (timer-counter unit) drivers
he's spent a very patient year or so working on. Plus some fixes for
X1000 SoCs from Zhou Yanjie.
- Netgear R6200 v1 systems are now supported by the bcm47xx platform.
- DT updates for BMIPS, Lantiq & Microsemi Ocelot systems.
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Merge tag 'mips_5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux
Pull MIPS updates from Paul Burton:
"Main MIPS changes:
- boot_mem_map is removed, providing a nice cleanup made possible by
the recent removal of bootmem.
- Some fixes to atomics, in general providing compiler barriers for
smp_mb__{before,after}_atomic plus fixes specific to Loongson CPUs
or MIPS32 systems using cmpxchg64().
- Conversion to the new generic VDSO infrastructure courtesy of
Vincenzo Frascino.
- Removal of undefined behavior in set_io_port_base(), fixing the
behavior of some MIPS kernel configurations when built with recent
clang versions.
- Initial MIPS32 huge page support, functional on at least Ingenic
SoCs.
- pte_special() is now supported for some configurations, allowing
among other things generic fast GUP to be used.
- Miscellaneous fixes & cleanups.
And platform specific changes:
- Major improvements to Ingenic SoC support from Paul Cercueil,
mostly enabled by the inclusion of the new TCU (timer-counter unit)
drivers he's spent a very patient year or so working on. Plus some
fixes for X1000 SoCs from Zhou Yanjie.
- Netgear R6200 v1 systems are now supported by the bcm47xx platform.
- DT updates for BMIPS, Lantiq & Microsemi Ocelot systems"
* tag 'mips_5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux: (89 commits)
MIPS: Detect bad _PFN_SHIFT values
MIPS: Disable pte_special() for MIPS32 with RiXi
MIPS: ralink: deactivate PCI support for SOC_MT7621
mips: compat: vdso: Use legacy syscalls as fallback
MIPS: Drop Loongson _CACHE_* definitions
MIPS: tlbex: Remove cpu_has_local_ebase
MIPS: tlbex: Simplify r3k check
MIPS: Select R3k-style TLB in Kconfig
MIPS: PCI: refactor ioc3 special handling
mips: remove ioremap_cachable
mips/atomic: Fix smp_mb__{before,after}_atomic()
mips/atomic: Fix loongson_llsc_mb() wreckage
mips/atomic: Fix cmpxchg64 barriers
MIPS: Octeon: remove duplicated include from dma-octeon.c
firmware: bcm47xx_nvram: Allow COMPILE_TEST
firmware: bcm47xx_nvram: Correct size_t printf format
MIPS: Treat Loongson Extensions as ASEs
MIPS: Remove dev_err() usage after platform_get_irq()
MIPS: dts: mscc: describe the PTP ready interrupt
MIPS: dts: mscc: describe the PTP register range
...
Pull core timer updates from Thomas Gleixner:
"Timers and timekeeping updates:
- A large overhaul of the posix CPU timer code which is a preparation
for moving the CPU timer expiry out into task work so it can be
properly accounted on the task/process.
An update to the bogus permission checks will come later during the
merge window as feedback was not complete before heading of for
travel.
- Switch the timerqueue code to use cached rbtrees and get rid of the
homebrewn caching of the leftmost node.
- Consolidate hrtimer_init() + hrtimer_init_sleeper() calls into a
single function
- Implement the separation of hrtimers to be forced to expire in hard
interrupt context even when PREEMPT_RT is enabled and mark the
affected timers accordingly.
- Implement a mechanism for hrtimers and the timer wheel to protect
RT against priority inversion and live lock issues when a (hr)timer
which should be canceled is currently executing the callback.
Instead of infinitely spinning, the task which tries to cancel the
timer blocks on a per cpu base expiry lock which is held and
released by the (hr)timer expiry code.
- Enable the Hyper-V TSC page based sched_clock for Hyper-V guests
resulting in faster access to timekeeping functions.
- Updates to various clocksource/clockevent drivers and their device
tree bindings.
- The usual small improvements all over the place"
* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (101 commits)
posix-cpu-timers: Fix permission check regression
posix-cpu-timers: Always clear head pointer on dequeue
hrtimer: Add a missing bracket and hide `migration_base' on !SMP
posix-cpu-timers: Make expiry_active check actually work correctly
posix-timers: Unbreak CONFIG_POSIX_TIMERS=n build
tick: Mark sched_timer to expire in hard interrupt context
hrtimer: Add kernel doc annotation for HRTIMER_MODE_HARD
x86/hyperv: Hide pv_ops access for CONFIG_PARAVIRT=n
posix-cpu-timers: Utilize timerqueue for storage
posix-cpu-timers: Move state tracking to struct posix_cputimers
posix-cpu-timers: Deduplicate rlimit handling
posix-cpu-timers: Remove pointless comparisons
posix-cpu-timers: Get rid of 64bit divisions
posix-cpu-timers: Consolidate timer expiry further
posix-cpu-timers: Get rid of zero checks
rlimit: Rewrite non-sensical RLIMIT_CPU comment
posix-cpu-timers: Respect INFINITY for hard RTTIME limit
posix-cpu-timers: Switch thread group sampling to array
posix-cpu-timers: Restructure expiry array
posix-cpu-timers: Remove cputime_expires
...
If we just use the CSRs that these map to directly the code is simpler
and doesn't require extra inline assembly code. Also fix up the top-level
comment in timer-riscv.c to not talk about the cycle count or mention
details of the clocksource interface, of which this file is just a
consumer.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
Update the CMT driver to mark "renesas,cmt-48" as deprecated.
Instead of documenting a theoretical hardware device based on current software
support level, define DT bindings top-down based on available data sheet
information and make use of part numbers in the DT compat string.
In case of the only in-tree users r8a7740 and sh73a0 the compat strings
"renesas,r8a7740-cmt1" and "renesas,sh73a0-cmt1" may be used instead.
Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Add SoC-specific matching for CMT1 on r8a7740 and sh73a0.
This allows us to move away from the old DT bindings such as
- "renesas,cmt-48-sh73a0"
- "renesas,cmt-48-r8a7740"
- "renesas,cmt-48"
in favour for the now commonly used format "renesas,<soc>-<device>"
Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Deferred probe is an expected return value on many platforms and so
there's no need to output a warning that may potentially confuse users.
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Deferred probe is an expected return value for clk_get() on many
platforms. The driver deals with it properly, so there's no need
to output a warning that may potentially confuse users.
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
NPCM7XX_Tx_OPER GENMASK bits are wrong, fix them.
Hopefully the NPCM7XX_REG_TICR0 register reset value of those bits was 0,
so it did not cause an issue.
The function npcm7xx_timer_oneshot() reads the register
NPCM7XX_REG_TCSR0, modifies it and then reads it again overwriting the
previous changes. Remove the extra read which is pointless.
The function npcm7xx_timer_periodic() is correct but the code writes
to the NPCM7XX_REG_TICR0 register while it is dealing with the
NPCM7XX_REG_TCSR0 register, that is confusing. Separate the write to
the registers in the code for the sake of clarity.
Fixes: 1c00289ecd ("clocksource/drivers/npcm: Add NPCM7xx timer driver")
Signed-off-by: Avi Fishman <avifishman70@gmail.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Use the DIV_ROUND_CLOSEST() helper instead of open-coding the same
operation.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
The system counter block guide states that the base clock is
internally divided by 3 before use, that means the clock input of
system counter defined in DT should be base clock which is normally
from OSC, and then internally divided by 3 before use.
Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Implement and register delay timer to allow get_cycles() to work properly.
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Newer Allwinner SoCs have different number of interrupts, let's add
different compatibles for all of them to deal with this properly.
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
We don't need dev_err() messages when platform_get_irq() fails now that
platform_get_irq() prints an error message itself when something goes
wrong. Let's remove these prints with a simple semantic patch.
// <smpl>
@@
expression ret;
struct platform_device *E;
@@
ret =
(
platform_get_irq(E, ...)
|
platform_get_irq_byname(E, ...)
);
if ( \( ret < 0 \| ret <= 0 \) )
{
(
-if (ret != -EPROBE_DEFER)
-{ ...
-dev_err(...);
-... }
|
...
-dev_err(...);
)
...
}
// </smpl>
While we're here, remove braces on if statements that only have one
statement (manually).
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
There is no particular reason to not enable TSC page clocksource on
32-bit. mul_u64_u64_shr() is available and despite the increased
computational complexity (compared to 64bit) TSC page is still a huge win
compared to MSR-based clocksource.
In-kernel reads:
MSR based clocksource: 3361 cycles
TSC page clocksource: 49 cycles
Reads from userspace (utilizing vDSO in case of TSC page):
MSR based clocksource: 5664 cycles
TSC page clocksource: 131 cycles
Enabling TSC page on 32bits allows to get rid of CONFIG_HYPERV_TSCPAGE as
it is now not any different from CONFIG_HYPERV_TIMER.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lkml.kernel.org/r/20190822083630.17059-1-vkuznets@redhat.com
Hyper-V guests use the default native_sched_clock() in
pv_ops.time.sched_clock on x86. But native_sched_clock() directly uses the
raw TSC value, which can be discontinuous in a Hyper-V VM.
Add the generic hv_setup_sched_clock() to set the sched clock function
appropriately. On x86, this sets pv_ops.time.sched_clock to read the
Hyper-V reference TSC value that is scaled and adjusted to be continuous.
Also move the Hyper-V reference TSC initialization much earlier in the boot
process so no discontinuity is observed when pv_ops.time.sched_clock
calculates its offset.
[ tglx: Folded build fix ]
Signed-off-by: Tianyu Lan <Tianyu.Lan@microsoft.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lkml.kernel.org/r/20190814123216.32245-3-Tianyu.Lan@microsoft.com
Prepare to add Hyper-V sched clock callback and move Hyper-V Reference TSC
initialization much earlier in the boot process. Earlier initialization is
needed so that it happens while the timestamp value is still 0 and no
discontinuity in the timestamp will occur when pv_ops.time.sched_clock
calculates its offset.
The earlier initialization requires that the Hyper-V TSC page be allocated
statically instead of with vmalloc(), so fixup the references to the TSC
page and the method of getting its physical address.
Signed-off-by: Tianyu Lan <Tianyu.Lan@microsoft.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lkml.kernel.org/r/20190814123216.32245-2-Tianyu.Lan@microsoft.com
This driver handles the TCU (Timer Counter Unit) present on the Ingenic
JZ47xx SoCs, and provides the kernel with a system timer, a clocksource
and a sched_clock.
Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Tested-by: Mathieu Malaterre <malat@debian.org>
Tested-by: Artur Rojek <contact@artur-rojek.eu>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Michael Turquette <mturquette@baylibre.com>
Cc: Stephen Boyd <sboyd@kernel.org>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: devicetree@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-doc@vger.kernel.org
Cc: linux-mips@vger.kernel.org
Cc: linux-clk@vger.kernel.org
Cc: od@zcrc.me
There is only one clocksource in RISC-V. The boot cpu initializes
that clocksource. No need to keep a percpu data structure.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Hyper-V clock/timer code and data structures are currently mixed
in with other code in the ISA independent drivers/hv directory as
well as the ISA dependent Hyper-V code under arch/x86.
Consolidate this code and data structures into a Hyper-V clocksource driver
to better follow the Linux model. In doing so, separate out the ISA
dependent portions so the new clocksource driver works for x86 and for the
in-process Hyper-V on ARM64 code.
To start, move the existing clockevents code to create the new clocksource
driver. Update the VMbus driver to call initialization and cleanup routines
since the Hyper-V synthetic timers are not independently enumerated in
ACPI.
No behavior is changed and no new functionality is added.
Suggested-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: "bp@alien8.de" <bp@alien8.de>
Cc: "will.deacon@arm.com" <will.deacon@arm.com>
Cc: "catalin.marinas@arm.com" <catalin.marinas@arm.com>
Cc: "mark.rutland@arm.com" <mark.rutland@arm.com>
Cc: "linux-arm-kernel@lists.infradead.org" <linux-arm-kernel@lists.infradead.org>
Cc: "gregkh@linuxfoundation.org" <gregkh@linuxfoundation.org>
Cc: "linux-hyperv@vger.kernel.org" <linux-hyperv@vger.kernel.org>
Cc: "olaf@aepfle.de" <olaf@aepfle.de>
Cc: "apw@canonical.com" <apw@canonical.com>
Cc: "jasowang@redhat.com" <jasowang@redhat.com>
Cc: "marcelo.cerri@canonical.com" <marcelo.cerri@canonical.com>
Cc: Sunil Muthuswamy <sunilmut@microsoft.com>
Cc: KY Srinivasan <kys@microsoft.com>
Cc: "sashal@kernel.org" <sashal@kernel.org>
Cc: "vincenzo.frascino@arm.com" <vincenzo.frascino@arm.com>
Cc: "linux-arch@vger.kernel.org" <linux-arch@vger.kernel.org>
Cc: "linux-mips@vger.kernel.org" <linux-mips@vger.kernel.org>
Cc: "linux-kselftest@vger.kernel.org" <linux-kselftest@vger.kernel.org>
Cc: "arnd@arndb.de" <arnd@arndb.de>
Cc: "linux@armlinux.org.uk" <linux@armlinux.org.uk>
Cc: "ralf@linux-mips.org" <ralf@linux-mips.org>
Cc: "paul.burton@mips.com" <paul.burton@mips.com>
Cc: "daniel.lezcano@linaro.org" <daniel.lezcano@linaro.org>
Cc: "salyzyn@android.com" <salyzyn@android.com>
Cc: "pcc@google.com" <pcc@google.com>
Cc: "shuah@kernel.org" <shuah@kernel.org>
Cc: "0x7f454c46@gmail.com" <0x7f454c46@gmail.com>
Cc: "linux@rasmusvillemoes.dk" <linux@rasmusvillemoes.dk>
Cc: "huw@codeweavers.com" <huw@codeweavers.com>
Cc: "sfr@canb.auug.org.au" <sfr@canb.auug.org.au>
Cc: "pbonzini@redhat.com" <pbonzini@redhat.com>
Cc: "rkrcmar@redhat.com" <rkrcmar@redhat.com>
Cc: "kvm@vger.kernel.org" <kvm@vger.kernel.org>
Link: https://lkml.kernel.org/r/1561955054-1838-2-git-send-email-mikelley@microsoft.com
Extend the davinci-timer driver to also register a clock source.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Currently the clocksource and clockevent support for davinci platforms
lives in mach-davinci. It hard-codes many things, uses global variables,
implements functionalities unused by any platform and has code fragments
scattered across many (often unrelated) files.
Implement a new, modern and simplified timer driver and put it into
drivers/clocksource. We still need to support legacy board files so
export a config structure and a function that allows machine code to
register the timer.
The timer we're using is 64-bit but can be programmed in dual 32-bit
mode (both chained and unchained).
On all davinci SoCs except for da830 we're using both halves. Lower half
for clockevents and upper half for clocksource. On da830 we're using the
lower half for both with the help of a compare register.
This patch contains the core code and support for clockevent. The
clocksource code will be included in a subsequent patch.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Tegra's timer has 29 bits for the counter and for the "load" register
which sets counter to a load-value. The counter's value is lower than
the actual value by 1 because it starts to decrement after one tick,
hence the maximum number of ticks that hardware can handle equals to
29 bits + 1.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Tegra's timer uses n+1 scheme for the counter, i.e. timer will fire after
one tick if 0 is loaded. The minimum and maximum numbers of oneshot ticks
are defined by clockevents_config_and_register(min, max) invocation and
the min value is set to 1 tick. Hence "cycles" value can't ever be 0,
unless it's a bug in clocksource core.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
We're adjusting the timer's base for each per-CPU timer to point to the
actual start of the timer since device-tree defines a compound registers
range that includes all of the timers. In this case the original base
need to be restore before calling iounmap to unmap the proper address.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Convert all 1MHz literals to a verbose constant for better readability.
Suggested-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
There is no need to cast void because kernel allows to do that without
a warning message from a compiler.
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
The of_clk structure has a period field that is set up initially by
timer_of_clk_init(), that period value need to be adjusted for a case of
TIMER1-9 that are running at a fixed rate that doesn't match the clock's
rate. Note that the period value is currently used only by some of the
clocksource drivers internally and hence this is just a minor cleanup
change that doesn't fix anything.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
It was left unnoticed by accident, which means that the code could be
cleaned up a tad more.
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Oliver Upton