KVM: arm64: nv: Sanitise CNTHCTL_EL2

Inject some sanity in CNTHCTL_EL2, ensuring that we don't handle
more than we advertise to the guest.

Acked-by: Oliver Upton <[email protected]>
Link: http

KVM: arm64: nv: Sanitise CNTHCTL_EL2

Inject some sanity in CNTHCTL_EL2, ensuring that we don't handle
more than we advertise to the guest.

Acked-by: Oliver Upton <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Marc Zyngier <[email protected]>

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KVM: arm64: nv: Use FEAT_ECV to trap access to EL0 timers

Although FEAT_NV2 makes most things fast, it also makes it impossible
to correctly emulate the timers, as the sysreg accesses are redirected

KVM: arm64: nv: Use FEAT_ECV to trap access to EL0 timers

Although FEAT_NV2 makes most things fast, it also makes it impossible
to correctly emulate the timers, as the sysreg accesses are redirected
to memory.

FEAT_ECV addresses this by giving a hypervisor the ability to trap
the EL02 sysregs as well as the virtual timer.

Add the required trap setting to make use of the feature, allowing
us to elide the ugly resync in the middle of the run loop.

Acked-by: Oliver Upton <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Marc Zyngier <[email protected]>

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KVM: arm64: nv: Add handling of EL2-specific timer registers

Add the required handling for EL2 and EL02 registers, as
well as EL1 registers used in the E2H context. This includes
handling the virtua

KVM: arm64: nv: Add handling of EL2-specific timer registers

Add the required handling for EL2 and EL02 registers, as
well as EL1 registers used in the E2H context. This includes
handling the virtual timer accesses when CNTHCTL_EL2.EL1TVT
or CNTHCTL_EL2.EL1TVCT are set.

Acked-by: Oliver Upton <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Marc Zyngier <[email protected]>

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KVM: arm64: timers: Use CNTPOFF_EL2 to offset the physical timer

With ECV and CNTPOFF_EL2, it is very easy to offer an offset for
the physical timer. So let's do just that.

Nothing can set the offs

KVM: arm64: timers: Use CNTPOFF_EL2 to offset the physical timer

With ECV and CNTPOFF_EL2, it is very easy to offer an offset for
the physical timer. So let's do just that.

Nothing can set the offset yet, so this should have no effect
whatsoever (famous last words...).

Reviewed-by: Colton Lewis <[email protected]>
Signed-off-by: Marc Zyngier <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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clocksource/drivers/arm_arch_timer: Use event stream scaling when available

With FEAT_ECV and the 1GHz counter, it is pretty likely that the
event stream divider doesn't fit in the field that holds

clocksource/drivers/arm_arch_timer: Use event stream scaling when available

With FEAT_ECV and the 1GHz counter, it is pretty likely that the
event stream divider doesn't fit in the field that holds the
divider value (we only have 4 bits to describe counter bits [15:0]

Thankfully, FEAT_ECV also provides a scaling mechanism to switch
the field to cover counter bits [23:8] instead.

Enable this on arm64 when ECV is available (32bit doesn't have
any detection infrastructure and is unlikely to be run on an
ARMv8.6 system anyway).

Signed-off-by: Marc Zyngier <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Daniel Lezcano <[email protected]>
Acked-by: Mark Rutland <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Daniel Lezcano <[email protected]>

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clocksource/drivers/arm_arch_timer: Remove any trace of the TVAL programming interface

TVAL usage is now long gone, get rid of the leftovers.

Signed-off-by: Marc Zyngier <[email protected]>
Link: http

clocksource/drivers/arm_arch_timer: Remove any trace of the TVAL programming interface

TVAL usage is now long gone, get rid of the leftovers.

Signed-off-by: Marc Zyngier <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Daniel Lezcano <[email protected]>

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clocksource/drivers/arm_arch_timer: Move system register timer programming over to CVAL

In order to cope better with high frequency counters, move the
programming of the timers from the countdown ti

clocksource/drivers/arm_arch_timer: Move system register timer programming over to CVAL

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 <[email protected]>
Reviewed-by: Mark Rutland <[email protected]>
Tested-by: Mark Rutland <[email protected]>
Signed-off-by: Marc Zyngier <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Daniel Lezcano <[email protected]>

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arm64: arch_timer: Implement support for interrupt-names

This allows the devicetree to correctly represent the available set of
timers, which varies from device to device, without the need for fake

arm64: arch_timer: Implement support for interrupt-names

This allows the devicetree to correctly represent the available set of
timers, which varies from device to device, without the need for fake
dummy interrupts for unavailable slots.

Also add the hyp-virt timer/PPI, which is not currently used, but worth
representing.

Reviewed-by: Tony Lindgren <[email protected]>
Reviewed-by: Linus Walleij <[email protected]>
Reviewed-by: Marc Zyngier <[email protected]>
Signed-off-by: Hector Martin <[email protected]>

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treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of th

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation this program is
distributed in the hope that it will be useful but without any
warranty without even the implied warranty of merchantability or
fitness for a particular purpose see the gnu general public license
for more details you should have received a copy of the gnu general
public license along with this program if not see http www gnu org
licenses

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 503 file(s).

Signed-off-by: Thomas Gleixner <[email protected]>
Reviewed-by: Alexios Zavras <[email protected]>
Reviewed-by: Allison Randal <[email protected]>
Reviewed-by: Enrico Weigelt <[email protected]>
Cc: [email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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clocksource/arm_arch_timer: Store physical timer IRQ number for KVM on VHE

A host running in VHE mode gets the EL2 physical timer as its time
source (accessed using the EL1 sysreg accessors, which g

clocksource/arm_arch_timer: Store physical timer IRQ number for KVM on VHE

A host running in VHE mode gets the EL2 physical timer as its time
source (accessed using the EL1 sysreg accessors, which get re-directed
to the EL2 sysregs by VHE).

The EL1 physical timer remains unused by the host kernel, allowing us to
pass that on directly to a KVM guest and saves us from emulating this
timer for the guest on VHE systems.

Store the EL1 Physical Timer's IRQ number in
struct arch_timer_kvm_info on VHE systems to allow KVM to use it.

Acked-by: Daniel Lezcano <[email protected]>
Signed-off-by: Andre Przywara <[email protected]>
Signed-off-by: Marc Zyngier <[email protected]>
Signed-off-by: Christoffer Dall <[email protected]>

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arm64: use WFE for long delays

The current delay implementation uses the yield instruction, which is a
hint that it is beneficial to schedule another thread. As this is a hint,
it may be implemented

arm64: use WFE for long delays

The current delay implementation uses the yield instruction, which is a
hint that it is beneficial to schedule another thread. As this is a hint,
it may be implemented as a NOP, causing all delays to be busy loops. This
is the case for many existing CPUs.

Taking advantage of the generic timer sending periodic events to all
cores, we can use WFE during delays to reduce power consumption. This is
beneficial only for delays longer than the period of the timer event
stream.

If timer event stream is not enabled, delays will behave as yield/busy
loops.

Signed-off-by: Julien Thierry <[email protected]>
Cc: Catalin Marinas <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Mark Rutland <[email protected]>
Signed-off-by: Will Deacon <[email protected]>

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arm_arch_timer: Expose event stream status

The arch timer configuration for a CPU might get reset after suspending
said CPU.

In order to reliably use the event stream in the kernel (e.g. for delays

arm_arch_timer: Expose event stream status

The arch timer configuration for a CPU might get reset after suspending
said CPU.

In order to reliably use the event stream in the kernel (e.g. for delays),
we keep track of the state where we can safely consider the event stream as
properly configured. After writing to cntkctl, we issue an ISB to ensure
that subsequent delay loops can rely on the event stream being enabled.

Signed-off-by: Julien Thierry <[email protected]>
Acked-by: Mark Rutland <[email protected]>
Cc: Marc Zyngier <[email protected]>
Cc: Russell King <[email protected]>
Cc: Catalin Marinas <[email protected]>
Cc: Will Deacon <[email protected]>
Signed-off-by: Will Deacon <[email protected]>

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clocksource: arm_arch_timer: add structs to describe MMIO timer

In preparation for ACPI GTDT support, this patch adds structs to
describe the MMIO timers indepedent of the firmware interface.

Subse

clocksource: arm_arch_timer: add structs to describe MMIO timer

In preparation for ACPI GTDT support, this patch adds structs to
describe the MMIO timers indepedent of the firmware interface.

Subsequent patches will use these to split the FW/HW probing logic, so
that the HW probing logic can be shared by ACPI and DT.

Signed-off-by: Fu Wei <[email protected]>
Reviewed-by: Hanjun Guo <[email protected]>
Signed-off-by: Mark Rutland <[email protected]>

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clocksource: arm_arch_timer: add a new enum for spi type

This patch add a new enum "arch_timer_spi_nr" and use it in the driver.
Just for code's readability, no functional change.

Signed-off-by: Fu

clocksource: arm_arch_timer: add a new enum for spi type

This patch add a new enum "arch_timer_spi_nr" and use it in the driver.
Just for code's readability, no functional change.

Signed-off-by: Fu Wei <[email protected]>
Acked-by: Mark Rutland <[email protected]>
Signed-off-by: Mark Rutland <[email protected]>

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clocksource: arm_arch_timer: move enums and defines to header file

To support the arm_arch_timer via ACPI we need to share defines and enums
between the driver and the ACPI parser code.
So we split

clocksource: arm_arch_timer: move enums and defines to header file

To support the arm_arch_timer via ACPI we need to share defines and enums
between the driver and the ACPI parser code.
So we split out the relevant defines and enums into arm_arch_timer.h.

No functional change.

Signed-off-by: Fu Wei <[email protected]>
Acked-by: Mark Rutland <[email protected]>
Tested-by: Xiongfeng Wang <[email protected]>
Signed-off-by: Mark Rutland <[email protected]>

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clocksource: arm_arch_timer: Remove arch_timer_get_timecounter

The only call of arch_timer_get_timecounter (in KVM) has been removed.

Signed-off-by: Julien Grall <[email protected]>
Acked-by: Ch

clocksource: arm_arch_timer: Remove arch_timer_get_timecounter

The only call of arch_timer_get_timecounter (in KVM) has been removed.

Signed-off-by: Julien Grall <[email protected]>
Acked-by: Christoffer Dall <[email protected]>
Signed-off-by: Christoffer Dall <[email protected]>

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clocksource: arm_arch_timer: Extend arch_timer_kvm_info to get the virtual IRQ

Currently, the firmware table is parsed by the virtual timer code in
order to retrieve the virtual timer interrupt. How

clocksource: arm_arch_timer: Extend arch_timer_kvm_info to get the virtual IRQ

Currently, the firmware table is parsed by the virtual timer code in
order to retrieve the virtual timer interrupt. However, this is already
done by the arch timer driver.

To avoid code duplication, extend arch_timer_kvm_info to get the virtual
IRQ.

Note that the KVM code will be modified in a subsequent patch.

Signed-off-by: Julien Grall <[email protected]>
Acked-by: Christoffer Dall <[email protected]>
Signed-off-by: Christoffer Dall <[email protected]>

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clocksource: arm_arch_timer: Gather KVM specific information in a structure

Introduce a structure which are filled up by the arch timer driver and
used by the virtual timer in KVM.

The first member

clocksource: arm_arch_timer: Gather KVM specific information in a structure

Introduce a structure which are filled up by the arch timer driver and
used by the virtual timer in KVM.

The first member of this structure will be the timecounter. More members
will be added later.

A stub for the new helper isn't introduced because KVM requires the arch
timer for both ARM64 and ARM32.

The function arch_timer_get_timecounter is kept for the time being and
will be dropped in a subsequent patch.

Signed-off-by: Julien Grall <[email protected]>
Acked-by: Christoffer Dall <[email protected]>
Signed-off-by: Christoffer Dall <[email protected]>

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arm64: KVM: Implement timer save/restore

Implement the timer save restore as a direct translation of
the assembly code version.

Signed-off-by: Marc Zyngier <[email protected]>

time: move the timecounter/cyclecounter code into its own file.

The timecounter code has almost nothing to do with the clocksource
code. Let it live in its own file. This will help isolate the
timec

time: move the timecounter/cyclecounter code into its own file.

The timecounter code has almost nothing to do with the clocksource
code. Let it live in its own file. This will help isolate the
timecounter users from the clocksource users in the source tree.

Signed-off-by: Richard Cochran <[email protected]>
Acked-by: Jeff Kirsher <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

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drivers: clocksource: add support for ARM architected timer event stream

The ARM architected timer can generate events (used for waking up
CPUs executing the wfe instruction) at a frequency represen

drivers: clocksource: add support for ARM architected timer event stream

The ARM architected timer can generate events (used for waking up
CPUs executing the wfe instruction) at a frequency represented as a
power-of-2 divisor of the clock rate.

An event stream might be used:
- To implement wfe-based timeouts for userspace locking implementations.
- To impose a timeout on a wfe for safeguarding against any programming
error in case an expected event is not generated.

This patch computes the event stream frequency aiming for a period
of 100us between events. It uses ARM/ARM64 specific backends to configure
and enable the event stream.

Cc: Lorenzo Pieralisi <[email protected]>
Reviewed-by: Catalin Marinas <[email protected]>
Acked-by: Olof Johansson <[email protected]>
Signed-off-by: Will Deacon <[email protected]>
[sudeep: moving ARM/ARM64 changes into separate patches
and adding Kconfig option]
Signed-off-by: Sudeep KarkadaNagesha <[email protected]>

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ARM/ARM64: arch_timer: add macros for bits in control register

Add macros to describe the bitfields in the ARM architected timer
control register to make code easy to understand.

Reviewed-by: Loren

ARM/ARM64: arch_timer: add macros for bits in control register

Add macros to describe the bitfields in the ARM architected timer
control register to make code easy to understand.

Reviewed-by: Lorenzo Pieralisi <[email protected]>
Reviewed-by: Will Deacon <[email protected]>
Acked-by: Catalin Marinas <[email protected]>
Acked-by: Olof Johansson <[email protected]>
Signed-off-by: Sudeep KarkadaNagesha <[email protected]>

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clocksource: arch_timer: Add support for memory mapped timers

Add support for the memory mapped timers by filling in the
read/write functions and adding some parsing code. Note that we
only register

clocksource: arch_timer: Add support for memory mapped timers

Add support for the memory mapped timers by filling in the
read/write functions and adding some parsing code. Note that we
only register one clocksource, preferring the cp15 based
clocksource over the mmio one.

To keep things simple we register one global clockevent. This
covers the case of UP and SMP systems with only mmio hardware and
systems where the memory mapped timers are used as the broadcast
timer in low power modes.

The DT binding allows for per-CPU memory mapped timers in case we
want to support that in the future, but the code isn't added
here. We also don't do much for hypervisor support, although it
should be possible to support it by searching for at least two
frames where one frame has the virtual capability and then
updating KVM timers to support it.

Cc: Mark Rutland <[email protected]>
Cc: Marc Zyngier <[email protected]>
Cc: Rob Herring <[email protected]>
Signed-off-by: Stephen Boyd <[email protected]>
Signed-off-by: Daniel Lezcano <[email protected]>
Acked-by: Mark Rutland <[email protected]>

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clocksource: arch_timer: Make register accessors less error-prone

Using an enum for the register we wish to access allows newer
compilers to determine if we've forgotten a case in our switch
stateme

clocksource: arch_timer: Make register accessors less error-prone

Using an enum for the register we wish to access allows newer
compilers to determine if we've forgotten a case in our switch
statement. This allows us to remove the BUILD_BUG() instances in
the arm64 port, avoiding problems where optimizations may not
happen.

To try and force better code generation we're currently marking
the accessor functions as inline, but newer compilers can ignore
the inline keyword unless it's marked __always_inline. Luckily on
arm and arm64 inline is __always_inline, but let's make
everything __always_inline to be explicit.

Suggested-by: Thomas Gleixner <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Marc Zyngier <[email protected]>
Signed-off-by: Stephen Boyd <[email protected]>
Signed-off-by: Daniel Lezcano <[email protected]>
Acked-by: Mark Rutland <[email protected]>

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clocksource: arch_timer: use virtual counters

Switching between reading the virtual or physical counters is
problematic, as some core code wants a view of time before we're fully
set up. Using a fun

clocksource: arch_timer: use virtual counters

Switching between reading the virtual or physical counters is
problematic, as some core code wants a view of time before we're fully
set up. Using a function pointer and switching the source after the
first read can make time appear to go backwards, and having a check in
the read function is an unfortunate block on what we want to be a fast
path.

Instead, this patch makes us always use the virtual counters. If we're a
guest, or don't have hyp mode, we'll use the virtual timers, and as such
don't care about CNTVOFF as long as it doesn't change in such a way as
to make time appear to travel backwards. As the guest will use the
virtual timers, a (potential) KVM host must use the physical timers
(which can wake up the host even if they fire while a guest is
executing), and hence a host must have CNTVOFF set to zero so as to have
a consistent view of time between the physical timers and virtual
counters.

Signed-off-by: Mark Rutland <[email protected]>
Acked-by: Catalin Marinas <[email protected]>
Acked-by: Marc Zyngier <[email protected]>
Acked-by: Santosh Shilimkar <[email protected]>
Cc: Rob Herring <[email protected]>

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