We had GIC specific defines for the IRQ type identifiers in kvmtool.
But in fact the specification of being a level or edge interrupt
is quite generic, with the GIC binding using the generic Linux
defines.
So lets replace the GIC specific #defines in favour of the more
general names copied from Linux' include/linux/irq.h.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
The new optional property "always-on" indicates that the timers
are, well, always on when used with KVM.
This allows for substantial performance improvement in the guest
(it switches to NOHZ instead of using a periodic tick per vcpu)
and removes a lot of burden from the host (no need to inject tons
of interrupts with the associated rescheduling overhead).
Old kernels that don't understand this property will simply ignore it.
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
Some platforms have secure firmware which does not correctly set the
CNTFRQ register on boot, preventing the use of the Generic Timer.
This patch allows mirroring the necessary host workaround by specifying
the clock-frequency property in the guest DT.
This should only be considered a means of KVM bring-up on such systems,
such that vendors may be convinced to properly implement their firmware
to support the virtualisation capabilities of their hardware.
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
The ARM V7 and V8 CPUs use the nearly identical support code for generating
timer DT nodes as they both use ARM's architected timers. This code is currently
duplicated for AArch32 and AArch64.
This cleanup patch generalises timer DT node generation to follow the same
pattern as for the GIC. The ability of a DT node to contain multiple compatible
strings is exploited to allow an identical DT node to be used on V7 and V8
platforms.
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Jonathan Austin <jonathan.austin@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
Andre Przywara