linux-stable.git/drivers/clocksource, branch v4.9.166

clocksource/drivers/exynos_mct: Clear timer interrupt when shutdown

2019-03-23T12:19:46+00:00

commit d2f276c8d3c224d5b493c42b6cf006ae4e64fb1c upstream.

When shutting down the timer, ensure that after we have stopped the
timer any pending interrupts are cleared. This fixes a problem when
suspending, as interrupts are disabled before the timer is stopped,
so the timer interrupt may still be asserted, preventing the system
entering a low power state when the wfi is executed.

Signed-off-by: Stuart Menefy 
Reviewed-by: Krzysztof Kozlowski 
Tested-by: Marek Szyprowski 
Cc:  # v4.3+
Signed-off-by: Daniel Lezcano 
Signed-off-by: Greg Kroah-Hartman

clocksource/drivers/exynos_mct: Move one-shot check from tick clear to ISR

2019-03-23T12:19:46+00:00

commit a5719a40aef956ba704f2aa1c7b977224d60fa96 upstream.

When a timer tick occurs and the clock is in one-shot mode, the timer
needs to be stopped to prevent it triggering subsequent interrupts.
Currently this code is in exynos4_mct_tick_clear(), but as it is
only needed when an ISR occurs move it into exynos4_mct_tick_isr(),
leaving exynos4_mct_tick_clear() just doing what its name suggests it
should.

Signed-off-by: Stuart Menefy 
Reviewed-by: Krzysztof Kozlowski 
Tested-by: Marek Szyprowski 
Cc: stable@vger.kernel.org # v4.3+
Signed-off-by: Daniel Lezcano 
Signed-off-by: Greg Kroah-Hartman

clockevents/drivers/i8253: Add support for PIT shutdown quirk

2018-11-21T08:26:01+00:00

commit 35b69a420bfb56b7b74cb635ea903db05e357bec upstream.

Add support for platforms where pit_shutdown() doesn't work because of a
quirk in the PIT emulation. On these platforms setting the counter register
to zero causes the PIT to start running again, negating the shutdown.

Provide a global variable that controls whether the counter register is
zero'ed, which platform specific code can override.

Signed-off-by: Michael Kelley 
Signed-off-by: Thomas Gleixner 
Cc: "gregkh@linuxfoundation.org" 
Cc: "devel@linuxdriverproject.org" 
Cc: "daniel.lezcano@linaro.org" 
Cc: "virtualization@lists.linux-foundation.org" 
Cc: "jgross@suse.com" 
Cc: "akataria@vmware.com" 
Cc: "olaf@aepfle.de" 
Cc: "apw@canonical.com" 
Cc: vkuznets 
Cc: "jasowang@redhat.com" 
Cc: "marcelo.cerri@canonical.com" 
Cc: KY Srinivasan 
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/1541303219-11142-2-git-send-email-mikelley@microsoft.com
Signed-off-by: Greg Kroah-Hartman

clocksource/drivers/ti-32k: Add CLOCK_SOURCE_SUSPEND_NONSTOP flag for non-am43 SoCs

2018-10-20T07:51:30+00:00

[ Upstream commit 3b7d96a0dbb6b630878597a1838fc39f808b761b ]

The 32k clocksource is NONSTOP for non-am43 SoCs. Hence
add the flag for all the other SoCs.

Reported-by: Tony Lindgren 
Signed-off-by: Keerthy 
Acked-by: Tony Lindgren 
Signed-off-by: Daniel Lezcano 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

clocksource/drivers/fsl_ftm_timer: Fix error return checking

2018-05-30T05:50:32+00:00

[ Upstream commit f287eb9013ccf199cbfa4eabd80c36fedfc15a73 ]

The error checks on freq for a negative error return always fails because
freq is unsigned and can never be negative. Fix this by making freq a
signed long.

Detected with Coccinelle:
drivers/clocksource/fsl_ftm_timer.c:287:5-9: WARNING: Unsigned expression
compared with zero: freq <= 0
drivers/clocksource/fsl_ftm_timer.c:291:5-9: WARNING: Unsigned expression
compared with zero: freq <= 0

Fixes: 2529c3a33079 ("clocksource: Add Freescale FlexTimer Module (FTM) timer support")
Signed-off-by: Colin Ian King 
Signed-off-by: Thomas Gleixner 
Cc: Daniel Lezcano 
Cc: kernel-janitors@vger.kernel.org
Link: https://lkml.kernel.org/r/20180226113614.3092-1-colin.king@canonical.com
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

clocksource/drivers/stm32: Fix kernel panic with multiple timers

2018-02-17T12:21:20+00:00

commit e0aeca3d8cbaea514eb98df1149faa918f9ec42d upstream.

The current code hides a couple of bugs:

 - The global variable 'clock_event_ddata' is overwritten each time the
   init function is invoked.

This is fixed with a kmemdup() instead of assigning the global variable. That
prevents a memory corruption when several timers are defined in the DT.

 - The clockevent's event_handler is NULL if the time framework does
   not select the clockevent when registering it, this is fine but the init
   code generates in any case an interrupt leading to dereference this
   NULL pointer.

The stm32 timer works with shadow registers, a mechanism to cache the
registers. When a change is done in one buffered register, we need to
artificially generate an event to force the timer to copy the content
of the register to the shadowed register.

The auto-reload register (ARR) is one of the shadowed register as well as
the prescaler register (PSC), so in order to force the copy, we issue an
event which in turn leads to an interrupt and the NULL dereference.

This is fixed by inverting two lines where we clear the status register
before enabling the update event interrupt.

As this kernel crash is resulting from the combination of these two bugs,
the fixes are grouped into a single patch.

Tested-by: Benjamin Gaignard 
Signed-off-by: Daniel Lezcano 
Acked-by: Benjamin Gaignard 
Cc: Alexandre Torgue 
Cc: Linus Torvalds 
Cc: Maxime Coquelin 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Link: http://lkml.kernel.org/r/1515418139-23276-11-git-send-email-daniel.lezcano@linaro.org
Signed-off-by: Ingo Molnar 
Signed-off-by: Greg Kroah-Hartman

clockevents/drivers/cs5535: Improve resilience to spurious interrupts

2017-10-27T08:38:08+00:00

commit eb39a7c0355393c5a8d930f342ad7a6231b552c4 upstream.

The interrupt handler mfgpt_tick() is not robust versus spurious interrupts
which happen before the clock event device is registered and fully
initialized.

The reason is that the safe guard against spurious interrupts solely checks
for the clockevents shutdown state, but lacks a check for detached
state. If the interrupt hits while the device is in detached state it
passes the safe guard and dereferences the event handler call back which is
NULL.

Add the missing state check.

Fixes: 8f9327cbb6e8 ("clockevents/drivers/cs5535: Migrate to new 'set-state' interface")
Suggested-by: Thomas Gleixner 
Signed-off-by: David Kozub 
Signed-off-by: Thomas Gleixner 
Cc: Daniel Lezcano 
Link: https://lkml.kernel.org/r/20171020093103.3317F6004D@linux.fjfi.cvut.cz
Signed-off-by: Greg Kroah-Hartman

clocksource/drivers/arm_arch_timer: Don't assume clock runs in suspend

2017-04-12T10:41:16+00:00

[ Upstream commit d8ec7595a013237f82d965dcf981571aeb41855b ]

The ARM specifies that the system counter "must be implemented in an
always-on power domain," and so we try to use the counter as a source of
timekeeping across suspend/resume. Unfortunately, some SoCs (e.g.,
Rockchip's RK3399) do not keep the counter ticking properly when
switched from their high-power clock to the lower-power clock used in
system suspend. Support this quirk by adding a new device tree property.

Signed-off-by: Brian Norris 
Reviewed-by: Douglas Anderson 
Acked-by: Marc Zyngier 
Signed-off-by: Daniel Lezcano 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

clocksource/exynos_mct: Clear interrupt when cpu is shut down

2017-01-26T07:24:40+00:00

commit bc7c36eedb0c7004aa06c2afc3c5385adada8fa3 upstream.

When a CPU goes offline a potentially pending timer interrupt is not
cleared. When the CPU comes online again then the pending interrupt is
delivered before the per cpu clockevent device is initialized. As a
consequence the tick interrupt handler dereferences a NULL pointer.

[   51.251378] Unable to handle kernel NULL pointer dereference at virtual address 00000040
[   51.289348] task: ee942d00 task.stack: ee960000
[   51.293861] PC is at tick_periodic+0x38/0xb0
[   51.298102] LR is at tick_handle_periodic+0x1c/0x90

Clear the pending interrupt in the cpu dying path.

Fixes: 56a94f13919c ("clocksource: exynos_mct: Avoid blocking calls in the cpu hotplug notifier")
Reported-by: Seung-Woo Kim 
Signed-off-by: Joonyoung Shim 
Cc: linux-samsung-soc@vger.kernel.org
Cc: cw00.choi@samsung.com
Cc: daniel.lezcano@linaro.org
Cc: javier@osg.samsung.com
Cc: kgene@kernel.org
Cc: krzk@kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1484628876-22065-1-git-send-email-jy0922.shim@samsung.com
Signed-off-by: Thomas Gleixner 
Signed-off-by: Greg Kroah-Hartman

Revert "clocksource/drivers/timer_sun5i: Replace code by clocksource_mmio_init"

2016-10-20T19:58:58+00:00

struct clocksource is also used by the clk notifier callback, to
unregister and re-register the clocksource with a different clock rate.
clocksource_mmio_init does not pass back a pointer to the struct used,
and the clk notifier callback assumes that the struct clocksource in
struct sun5i_timer_clksrc is valid. This results in a kernel NULL
pointer dereference when the hstimer clock is changed:

Unable to handle kernel NULL pointer dereference at virtual address 00000004
[] (clocksource_unbind) from [] (clocksource_unregister+0x2c/0x44)
[] (clocksource_unregister) from [] (sun5i_rate_cb_clksrc+0x34/0x3c)
[] (sun5i_rate_cb_clksrc) from [] (notifier_call_chain+0x44/0x84)
[] (notifier_call_chain) from [] (__srcu_notifier_call_chain+0x44/0x60)
[] (__srcu_notifier_call_chain) from [] (srcu_notifier_call_chain+0x18/0x20)
[] (srcu_notifier_call_chain) from [] (__clk_notify+0x70/0x7c)
[] (__clk_notify) from [] (clk_propagate_rate_change+0xa4/0xc4)
[] (clk_propagate_rate_change) from [] (clk_propagate_rate_change+0x6c/0xc4)

Revert the commit for now. clocksource_mmio_init can be made to pass back
a pointer, but the code churn and usage of an inner struct might not be
worth it.

Fixes: 157dfadef832 ("clocksource/drivers/timer_sun5i: Replace code by clocksource_mmio_init")
Reported-by: Maxime Ripard 
Signed-off-by: Chen-Yu Tsai 
Cc: linux-sunxi@googlegroups.com
Cc: Daniel Lezcano 
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/20161018054918.26855-1-wens@csie.org
Signed-off-by: Thomas Gleixner