<feed xmlns='http://www.w3.org/2005/Atom'>
<title>kernel/linux.git/drivers/clocksource, branch v6.1.2</title>
<subtitle>Linux kernel stable tree (mirror)</subtitle>
<id>https://git.radix-linux.su/kernel/linux.git/atom?h=v6.1.2</id>
<link rel='self' href='https://git.radix-linux.su/kernel/linux.git/atom?h=v6.1.2'/>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/'/>
<updated>2022-12-31T12:31:59+00:00</updated>
<entry>
<title>clocksource/drivers/timer-ti-dm: Fix missing clk_disable_unprepare in dmtimer_systimer_init_clock()</title>
<updated>2022-12-31T12:31:59+00:00</updated>
<author>
<name>Yang Yingliang</name>
<email>yangyingliang@huawei.com</email>
</author>
<published>2022-10-29T11:44:27+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=404b4b9770d88a1a81147ecee354da412c7267cd'/>
<id>urn:sha1:404b4b9770d88a1a81147ecee354da412c7267cd</id>
<content type='text'>
[ Upstream commit 180d35a7c05d520314a590c99ad8643d0213f28b ]

If clk_get_rate() fails which is called after clk_prepare_enable(),
clk_disable_unprepare() need be called in error path to disable the
clock in dmtimer_systimer_init_clock().

Fixes: 52762fbd1c47 ("clocksource/drivers/timer-ti-dm: Add clockevent and clocksource support")
Signed-off-by: Yang Yingliang &lt;yangyingliang@huawei.com&gt;
Reviewed-by: Tony Lindgren &lt;tony@atomide.com&gt;
Link: https://lore.kernel.org/r/20221029114427.946520-1-yangyingliang@huawei.com
Signed-off-by: Daniel Lezcano &lt;daniel.lezcano@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>clocksource/drivers/timer-ti-dm: Fix warning for omap_timer_match</title>
<updated>2022-12-31T12:31:59+00:00</updated>
<author>
<name>Tony Lindgren</name>
<email>tony@atomide.com</email>
</author>
<published>2022-10-28T10:35:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=6b0a5f9e153ef06f47ae74ecb69beaf575f5f08c'/>
<id>urn:sha1:6b0a5f9e153ef06f47ae74ecb69beaf575f5f08c</id>
<content type='text'>
[ Upstream commit 9688498b1648aa98a3ee45d9f07763c099f6fb12 ]

We can now get a warning for 'omap_timer_match' defined but not used.
Let's fix this by dropping of_match_ptr for omap_timer_match.

Reported-by: kernel test robot &lt;lkp@intel.com&gt;
Fixes: ab0bbef3ae0f ("clocksource/drivers/timer-ti-dm: Make timer selectable for ARCH_K3")
Signed-off-by: Tony Lindgren &lt;tony@atomide.com&gt;
Link: https://lore.kernel.org/r/20221028103526.40319-1-tony@atomide.com
Signed-off-by: Daniel Lezcano &lt;daniel.lezcano@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>clocksource/drivers/sh_cmt: Access registers according to spec</title>
<updated>2022-12-31T12:31:58+00:00</updated>
<author>
<name>Wolfram Sang</name>
<email>wsa+renesas@sang-engineering.com</email>
</author>
<published>2022-11-30T21:06:09+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=fba0ec3a25ee84d5662bca6908a5d4cc7a422e04'/>
<id>urn:sha1:fba0ec3a25ee84d5662bca6908a5d4cc7a422e04</id>
<content type='text'>
[ Upstream commit 3f44f7156f59cae06e9160eafb5d8b2dfd09e639 ]

Documentation for most CMTs say that it takes two input clocks before
changes propagate to the timer. This is especially relevant when the timer
is stopped to change further settings.

Implement the delays according to the spec. To avoid unnecessary delays in
atomic mode, also check if the to-be-written value actually differs.

CMCNT is a bit special because testing showed that it requires 3 cycles to
propagate, which affects all CMTs. Also, the WRFLAG needs to be checked
before writing. This fixes "cannot clear CMCNT" messages which occur often
on R-Car Gen4 SoCs, but only very rarely on older SoCs for some reason.

Fixes: 81b3b2711072 ("clocksource: sh_cmt: Add support for multiple channels per device")
Signed-off-by: Wolfram Sang &lt;wsa+renesas@sang-engineering.com&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Link: https://lore.kernel.org/r/20221130210609.7718-1-wsa+renesas@sang-engineering.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>Revert "clocksource/drivers/riscv: Events are stopped during CPU suspend"</title>
<updated>2022-12-01T11:05:29+00:00</updated>
<author>
<name>Conor Dooley</name>
<email>conor.dooley@microchip.com</email>
</author>
<published>2022-11-22T12:16:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=d9f15a9de44affe733e34f93bc184945ba277e6d'/>
<id>urn:sha1:d9f15a9de44affe733e34f93bc184945ba277e6d</id>
<content type='text'>
This reverts commit 232ccac1bd9b5bfe73895f527c08623e7fa0752d.

On the subject of suspend, the RISC-V SBI spec states:

  This does not cover whether any given events actually reach the hart or
  not, just what the hart will do if it receives an event. On PolarFire
  SoC, and potentially other SiFive based implementations, events from the
  RISC-V timer do reach a hart during suspend. This is not the case for the
  implementation on the Allwinner D1 - there timer events are not received
  during suspend.

To fix this, the CLOCK_EVT_FEAT_C3STOP (mis)feature was enabled for the
timer driver - but this has broken both RCU stall detection and timers
generally on PolarFire SoC and potentially other SiFive based
implementations.

If an AXI read to the PCIe controller on PolarFire SoC times out, the
system will stall, however, with CLOCK_EVT_FEAT_C3STOP active, the system
just locks up without RCU stalling:

	io scheduler mq-deadline registered
	io scheduler kyber registered
	microchip-pcie 2000000000.pcie: host bridge /soc/pcie@2000000000 ranges:
	microchip-pcie 2000000000.pcie:      MEM 0x2008000000..0x2087ffffff -&gt; 0x0008000000
	microchip-pcie 2000000000.pcie: sec error in pcie2axi buffer
	microchip-pcie 2000000000.pcie: ded error in pcie2axi buffer
	microchip-pcie 2000000000.pcie: axi read request error
	microchip-pcie 2000000000.pcie: axi read timeout
	microchip-pcie 2000000000.pcie: sec error in pcie2axi buffer
	microchip-pcie 2000000000.pcie: ded error in pcie2axi buffer
	microchip-pcie 2000000000.pcie: sec error in pcie2axi buffer
	microchip-pcie 2000000000.pcie: ded error in pcie2axi buffer
	microchip-pcie 2000000000.pcie: sec error in pcie2axi buffer
	microchip-pcie 2000000000.pcie: ded error in pcie2axi buffer
	Freeing initrd memory: 7332K

Similarly issues were reported with clock_nanosleep() - with a test app
that sleeps each cpu for 6, 5, 4, 3 ms respectively, HZ=250 &amp; the blamed
commit in place, the sleep times are rounded up to the next jiffy:

== CPU: 1 ==      == CPU: 2 ==      == CPU: 3 ==      == CPU: 4 ==
Mean: 7.974992    Mean: 7.976534    Mean: 7.962591    Mean: 3.952179
Std Dev: 0.154374 Std Dev: 0.156082 Std Dev: 0.171018 Std Dev: 0.076193
Hi: 9.472000      Hi: 10.495000     Hi: 8.864000      Hi: 4.736000
Lo: 6.087000      Lo: 6.380000      Lo: 4.872000      Lo: 3.403000
Samples: 521      Samples: 521      Samples: 521      Samples: 521

Fortunately, the D1 has a second timer, which is "currently used in
preference to the RISC-V/SBI timer driver" so a revert here does not
hurt operation of D1 in its current form.

Ultimately, a DeviceTree property (or node) will be added to encode the
behaviour of the timers, but until then revert the addition of
CLOCK_EVT_FEAT_C3STOP.

Fixes: 232ccac1bd9b ("clocksource/drivers/riscv: Events are stopped during CPU suspend")
Signed-off-by: Conor Dooley &lt;conor.dooley@microchip.com&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Reviewed-by: Palmer Dabbelt &lt;palmer@rivosinc.com&gt;
Acked-by: Palmer Dabbelt &lt;palmer@rivosinc.com&gt;
Acked-by: Samuel Holland &lt;samuel@sholland.org&gt;
Link: https://lore.kernel.org/linux-riscv/YzYTNQRxLr7Q9JR0@spud/
Link: https://github.com/riscv-non-isa/riscv-sbi-doc/issues/98/
Link: https://lore.kernel.org/linux-riscv/bf6d3b1f-f703-4a25-833e-972a44a04114@sholland.org/
Link: https://lore.kernel.org/r/20221122121620.3522431-1-conor.dooley@microchip.com

</content>
</entry>
<entry>
<title>clocksource/drivers/arm_arch_timer: Fix XGene-1 TVAL register math error</title>
<updated>2022-11-21T15:01:56+00:00</updated>
<author>
<name>Joe Korty</name>
<email>joe.korty@concurrent-rt.com</email>
</author>
<published>2022-11-21T14:53:43+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=839a973988a94c15002cbd81536e4af6ced2bd30'/>
<id>urn:sha1:839a973988a94c15002cbd81536e4af6ced2bd30</id>
<content type='text'>
The TVAL register is 32 bit signed.  Thus only the lower 31 bits are
available to specify when an interrupt is to occur at some time in the
near future.  Attempting to specify a larger interval with TVAL results
in a negative time delta which means the timer fires immediately upon
being programmed, rather than firing at that expected future time.

The solution is for Linux to declare that TVAL is a 31 bit register rather
than give its true size of 32 bits.  This prevents Linux from programming
TVAL with a too-large value.  Note that, prior to 5.16, this little trick
was the standard way to handle TVAL in Linux, so there is nothing new
happening here on that front.

The softlockup detector hides the issue, because it keeps generating
short timer deadlines that are within the scope of the broken timer.

Disabling it, it starts using NO_HZ with much longer timer deadlines, which
turns into an interrupt flood:

 11: 1124855130  949168462  758009394   76417474  104782230   30210281
         310890 1734323687     GICv2  29 Level     arch_timer

And "much longer" isn't that long: it takes less than 43s to underflow
TVAL at 50MHz (the frequency of the counter on XGene-1).

Some comments on the v1 version of this patch by Marc Zyngier:

  XGene implements CVAL (a 64bit comparator) in terms of TVAL (a countdown
  register) instead of the other way around. TVAL being a 32bit register,
  the width of the counter should equally be 32.  However, TVAL is a
  *signed* value, and keeps counting down in the negative range once the
  timer fires.

  It means that any TVAL value with bit 31 set will fire immediately,
  as it cannot be distinguished from an already expired timer. Reducing
  the timer range back to a paltry 31 bits papers over the issue.

  Another problem cannot be fixed though, which is that the timer interrupt
  *must* be handled within the negative countdown period, or the interrupt
  will be lost (TVAL will rollover to a positive value, indicative of a
  new timer deadline).

Fixes: 012f18850452 ("clocksource/drivers/arm_arch_timer: Work around broken CVAL implementations")
Signed-off-by: Joe Korty &lt;joe.korty@concurrent-rt.com&gt;
Signed-off-by: Marc Zyngier &lt;maz@kernel.org&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Reviewed-by: Marc Zyngier &lt;maz@kernel.org&gt;
Link: https://lore.kernel.org/r/20221024165422.GA51107@zipoli.concurrent-rt.com
Link: https://lore.kernel.org/r/20221121145343.896018-1-maz@kernel.org

[maz: revamped the commit message]
</content>
</entry>
<entry>
<title>clocksource/drivers/hyperv: add data structure for reference TSC MSR</title>
<updated>2022-11-03T15:50:28+00:00</updated>
<author>
<name>Anirudh Rayabharam</name>
<email>anrayabh@linux.microsoft.com</email>
</author>
<published>2022-10-27T09:57:28+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=4ad1aa571214e8d6468a1806794d987b374b5a08'/>
<id>urn:sha1:4ad1aa571214e8d6468a1806794d987b374b5a08</id>
<content type='text'>
Add a data structure to represent the reference TSC MSR similar to
other MSRs. This simplifies the code for updating the MSR.

Signed-off-by: Anirudh Rayabharam &lt;anrayabh@linux.microsoft.com&gt;
Reviewed-by: Michael Kelley &lt;mikelley@microsoft.com&gt;
Link: https://lore.kernel.org/r/20221027095729.1676394-2-anrayabh@linux.microsoft.com
Signed-off-by: Wei Liu &lt;wei.liu@kernel.org&gt;
</content>
</entry>
<entry>
<title>Merge tag 'timers-core-2022-10-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2022-10-10T17:16:00+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-10-10T17:16:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=55be6084c8e0e0ada9278c2ab60b7a584378efda'/>
<id>urn:sha1:55be6084c8e0e0ada9278c2ab60b7a584378efda</id>
<content type='text'>
Pull timer updates from Thomas Gleixner:
 "A boring time, timekeeping, timers update:

   - No core code changes

   - No new clocksource/event driver

   - Cleanup of the TI DM clocksource/event driver

   - The usual set of device tree binding updates

   - Small improvement, fixes and cleanups all over the place"

* tag 'timers-core-2022-10-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (22 commits)
  clocksource/drivers/arm_arch_timer: Fix CNTPCT_LO and CNTVCT_LO value
  clocksource/drivers/imx-sysctr: handle nxp,no-divider property
  dt-bindings: timer: nxp,sysctr-timer: add nxp,no-divider property
  clocksource/drivers/timer-ti-dm: Get clock in probe with devm_clk_get()
  clocksource/drivers/timer-ti-dm: Add flag to detect omap1
  clocksource/drivers/timer-ti-dm: Move struct omap_dm_timer fields to driver
  clocksource/drivers/timer-ti-dm: Use runtime PM directly and check errors
  clocksource/drivers/timer-ti-dm: Move private defines to the driver
  clocksource/drivers/timer-ti-dm: Simplify register access further
  clocksource/drivers/timer-ti-dm: Simplify register writes with dmtimer_write()
  clocksource/drivers/timer-ti-dm: Simplify register reads with dmtimer_read()
  clocksource/drivers/timer-ti-dm: Drop unused functions
  clocksource/drivers/timer-gxp: Add missing error handling in gxp_timer_probe
  clocksource/drivers/arm_arch_timer: Fix handling of ARM erratum 858921
  clocksource/drivers/exynos_mct: Enable building on ARTPEC
  clocksource/drivers/exynos_mct: Support local-timers property
  clocksource/drivers/exynos_mct: Support frc-shared property
  dt-bindings: timer: exynos4210-mct: Add ARTPEC-8 MCT support
  clocksource/drivers/sun4i: Add definition of clear interrupt
  clocksource/drivers/renesas-ostm: Add support for RZ/V2L SoC
  ...
</content>
</entry>
<entry>
<title>clocksource/drivers/arm_arch_timer: Fix CNTPCT_LO and CNTVCT_LO value</title>
<updated>2022-09-27T09:30:53+00:00</updated>
<author>
<name>Yang Guo</name>
<email>guoyang2@huawei.com</email>
</author>
<published>2022-09-27T03:32:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=af246cc6d0ed11318223606128bb0b09866c4c08'/>
<id>urn:sha1:af246cc6d0ed11318223606128bb0b09866c4c08</id>
<content type='text'>
CNTPCT_LO and CNTVCT_LO are defined by mistake in commit '8b82c4f883a7',
so fix them according to the Arm ARM DDI 0487I.a, Table I2-4
"CNTBaseN memory map" as follows:

Offset    Register      Type Description
0x000     CNTPCT[31:0]  RO   Physical Count register.
0x004     CNTPCT[63:32] RO
0x008     CNTVCT[31:0]  RO   Virtual Count register.
0x00C     CNTVCT[63:32] RO

Fixes: 8b82c4f883a7 ("clocksource/drivers/arm_arch_timer: Move MMIO timer programming over to CVAL")
Cc: stable@vger.kernel.org
Cc: Daniel Lezcano &lt;daniel.lezcano@linaro.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Marc Zyngier &lt;maz@kernel.org&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Acked-by: Marc Zyngier &lt;maz@kernel.org&gt;
Signed-off-by: Yang Guo &lt;guoyang2@huawei.com&gt;
Signed-off-by: Shaokun Zhang &lt;zhangshaokun@hisilicon.com&gt;
Link: https://lore.kernel.org/r/20220927033221.49589-1-zhangshaokun@hisilicon.com
Signed-off-by: Daniel Lezcano &lt;daniel.lezcano@linaro.org&gt;
</content>
</entry>
<entry>
<title>clocksource/drivers/imx-sysctr: handle nxp,no-divider property</title>
<updated>2022-09-20T08:49:46+00:00</updated>
<author>
<name>Peng Fan</name>
<email>peng.fan@nxp.com</email>
</author>
<published>2022-09-02T11:12:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=27b30995b75d1e79360c164ba179bca86ab76ba6'/>
<id>urn:sha1:27b30995b75d1e79360c164ba179bca86ab76ba6</id>
<content type='text'>
The previous hardware design embedds a internal divider for base clock.
New design not has that divider, so check the nxp,no-divider property,
if true, directly use base clock input, otherwise divide by 3 as before.

Signed-off-by: Peng Fan &lt;peng.fan@nxp.com&gt;
Link: https://lore.kernel.org/r/20220902111207.2902493-3-peng.fan@oss.nxp.com
Signed-off-by: Daniel Lezcano &lt;daniel.lezcano@linaro.org&gt;
</content>
</entry>
<entry>
<title>clocksource/drivers/timer-ti-dm: Get clock in probe with devm_clk_get()</title>
<updated>2022-09-20T08:49:46+00:00</updated>
<author>
<name>Tony Lindgren</name>
<email>tony@atomide.com</email>
</author>
<published>2022-08-15T13:12:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=789d4b1070261fa98b06384d2067f23c080dc9f1'/>
<id>urn:sha1:789d4b1070261fa98b06384d2067f23c080dc9f1</id>
<content type='text'>
We can simplify the code a bit by getting the clock in probe, and using
devm_clk_get(). This will also make further changes easier as the clock
is available in probe instead of prepare.

Signed-off-by: Tony Lindgren &lt;tony@atomide.com&gt;
Reviewed-by: Janusz Krzysztofik &lt;jmkrzyszt@gmail.com&gt;
Link: https://lore.kernel.org/r/20220815131250.34603-10-tony@atomide.com
Signed-off-by: Daniel Lezcano &lt;daniel.lezcano@linaro.org&gt;
</content>
</entry>
</feed>
