[ Upstream commit bc6717d55d07110d8f3c6d31ec2af50c11b07091 ]
When the timer counts to the upper limit, an overflow interrupt is
generated, and the count is reset with the value in the TIME_INI
register. But the software expects to start counting from 0 when
the count overflows, so it forces TIME_INI to 0 to solve the
potential interrupt storm problem.
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Tested-by: Xu Kai <xukai@nationalchip.com>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/1597735877-71115-1-git-send-email-guoren@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 400d033f5a599120089b5f0c54d14d198499af5a ]
In the init function, if the call to of_iomap() fails, the return
value is ENXIO instead of -ENXIO.
Change to the right negative errno.
Fixes: 691f8f878290f ("clocksource/drivers/h8300_timer8: Convert init function to return error")
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Tianjia Zhang <tianjia.zhang@linux.alibaba.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20200802111541.5429-1-tianjia.zhang@linux.alibaba.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 4b661d6133c5d3a7c9aca0b4ee5a78c7766eff3f upstream.
ARM64_WORKAROUND_1418040 requires that AArch32 EL0 accesses to
the virtual counter register are trapped and emulated by the kernel.
This makes the vdso pretty pointless, and in some cases livelock
prone.
Provide a workaround entry that limits the vdso to 64bit tasks.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200706163802.1836732-4-maz@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c1fbec4ac0d701f350a581941d35643d5a9cd184 upstream.
As we are about to disable the vdso for compat tasks in some circumstances,
let's allow a workaround descriptor to express exactly that.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200706163802.1836732-3-maz@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 97884ca8c2925d14c32188e865069f21378b4b4f upstream.
[this is a redesign rather than a backport]
We have a class of errata (grouped under the ARM64_WORKAROUND_1418040
banner) that force the trapping of counter access from 32bit EL0.
We would normally disable the whole vdso for such defect, except that
it would disable it for 64bit userspace as well, which is a shame.
Instead, add a new vdso_clock_mode, which signals that the vdso
isn't usable for compat tasks. This gets checked in the new
vdso_clocksource_ok() helper, now provided for the 32bit vdso.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200706163802.1836732-2-maz@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 6d2e16a3181bafb77b535095c39ad1c8b9558c8c ]
Commit 100214889973 ("clocksource: dw_apb_timer_of: use
clocksource_of_init") replaced a publicly available driver
initialization method with one called by the timer_probe() method
available after CLKSRC_OF. In current implementation it traverses
all the timers available in the system and calls their initialization
methods if corresponding devices were either in dtb or in acpi. But
if before the commit any number of available timers would be installed
as clockevent and clocksource devices, after that there would be at most
two. The rest are just ignored since default case branch doesn't do
anything. I don't see a reason of such behaviour, neither the commit
message explains it. Moreover this might be wrong if on some platforms
these timers might be used for different purpose, as virtually CPU-local
clockevent timers and as an independent broadcast timer. So in order
to keep the compatibility with the platforms where the order of the
timers detection has some meaning, lets add the secondly discovered
timer to be of clocksource/sched_clock type, while the very first and
the others would provide the clockevents service.
Fixes: 100214889973 ("clocksource: dw_apb_timer_of: use clocksource_of_init")
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Paul Burton <paulburton@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: linux-rtc@vger.kernel.org
Cc: devicetree@vger.kernel.org
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20200521204818.25436-7-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit cee43dbf2ee3f430434e2b66994eff8a1aeda889 ]
Currently the DW APB Timer driver binds each clockevent timers to a
particular CPU. This isn't good for multiple reasons. First of all seeing
the device is placed on APB bus (which makes it accessible from any CPU
core), accessible over MMIO and having the DYNIRQ flag set we can be sure
that manually binding the timer to any CPU just isn't correct. By doing
so we just set an extra limitation on device usage. This also doesn't
reflect the device actual capability, since by setting the IRQ affinity
we can make it virtually local to any CPU. Secondly imagine if you had a
real CPU-local timer with the same rating and the same CPU-affinity.
In this case if DW APB timer was registered first, then due to the
clockevent framework tick-timer selection procedure we'll end up with the
real CPU-local timer being left unselected for clock-events tracking. But
on most of the platforms (MIPS/ARM/etc) such timers are normally embedded
into the CPU core and are accessible with much better performance then
devices placed on APB. For instance in MIPS architectures there is
r4k-timer, which is CPU-local, assigned with the same rating, and normally
its clockevent device is registered after the platform-specific one.
So in order to fix all of these issues let's make the DW APB Timer CPU
affinity being optional and deactivated by passing a negative CPU id,
which will effectively set the DW APB clockevent timer cpumask to
'cpu_possible_mask'.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Paul Burton <paulburton@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: linux-rtc@vger.kernel.org
Cc: devicetree@vger.kernel.org
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20200521204818.25436-5-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Sasha Levin <sashal@kernel.org>
Guo Ren