linux-toradex.git/include/clocksource/arm_arch_timer.h, branch v5.1-rc1 Linux kernel for Apalis and Colibri modules clocksource/arm_arch_timer: Store physical timer IRQ number for KVM on VHE 2019-02-19T21:05:22+00:00 Andre Przywara andre.przywara@arm.com 2018-07-06T08:11:50+00:00 ee7930490a8f84570e96268f5736e99570b58307 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 <daniel.lezcano@linaro.org> Signed-off-by: Andre Przywara <andre.przywara@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@arm.com> 
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 <daniel.lezcano@linaro.org>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@arm.com>
arm64: use WFE for long delays 2017-10-13T17:56:15+00:00 Julien Thierry julien.thierry@arm.com 2017-10-13T13:32:56+00:00 7b77452ec524fa845efdec28ae16e2202cf797dc 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 <julien.thierry@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> 
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 <julien.thierry@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
arm_arch_timer: Expose event stream status 2017-10-13T17:55:05+00:00 Julien Thierry julien.thierry@arm.com 2017-10-13T13:32:55+00:00 ec5c8e429d07737ee94ee1fd2ae5029547484194 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 <julien.thierry@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> 
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 <julien.thierry@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
clocksource: arm_arch_timer: add structs to describe MMIO timer 2017-04-19T15:11:48+00:00 Fu Wei fu.wei@linaro.org 2017-03-31T17:50:59+00:00 b3251b8fd12337bf04bce46d4af35988742eef95 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 <fu.wei@linaro.org> Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org> Signed-off-by: Mark Rutland <mark.rutland@arm.com> 
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 <fu.wei@linaro.org>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
clocksource: arm_arch_timer: add a new enum for spi type 2017-04-10T13:29:54+00:00 Fu Wei fu.wei@linaro.org 2017-01-18T13:25:29+00:00 097cd143dd871bfceacf4ed252b177cf515a1888 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 <fu.wei@linaro.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Mark Rutland <mark.rutland@arm.com> 
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 <fu.wei@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
clocksource: arm_arch_timer: move enums and defines to header file 2017-04-10T13:29:54+00:00 Fu Wei fu.wei@linaro.org 2017-01-18T13:25:28+00:00 831610c08e63b69b141c446c78eb9e9315660a5d 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 <fu.wei@linaro.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Tested-by: Xiongfeng Wang <wangxiongfeng2@huawei.com> Signed-off-by: Mark Rutland <mark.rutland@arm.com> 
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 <fu.wei@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
clocksource: arm_arch_timer: Remove arch_timer_get_timecounter 2016-05-03T10:54:21+00:00 Julien Grall julien.grall@arm.com 2016-04-11T15:33:00+00:00 a53d892dfb6f14f77c508e1027f5e1bdb400fd23 The only call of arch_timer_get_timecounter (in KVM) has been removed. Signed-off-by: Julien Grall <julien.grall@arm.com> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> 
The only call of arch_timer_get_timecounter (in KVM) has been removed.

Signed-off-by: Julien Grall <julien.grall@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
clocksource: arm_arch_timer: Extend arch_timer_kvm_info to get the virtual IRQ 2016-05-03T10:54:21+00:00 Julien Grall julien.grall@arm.com 2016-04-11T15:32:52+00:00 d9b5e41591ca6bc6678e287b5ffe7fac2e07436e 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 <julien.grall@arm.com> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> 
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 <julien.grall@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
clocksource: arm_arch_timer: Gather KVM specific information in a structure 2016-05-03T10:54:20+00:00 Julien Grall julien.grall@arm.com 2016-04-11T15:32:51+00:00 b4d6ce9776e0fb773418efe8bc81d8c5ccca3493 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 <julien.grall@arm.com> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> 
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 <julien.grall@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
arm64: KVM: Implement timer save/restore 2015-12-14T11:30:39+00:00 Marc Zyngier marc.zyngier@arm.com 2015-10-19T15:32:20+00:00 1431af367e52b08038e78d346822966d968f1694 Implement the timer save restore as a direct translation of the assembly code version. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> 
Implement the timer save restore as a direct translation of
the assembly code version.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>