The GIC Hypervisor Configuration Register is used to enable
the delivery of virtual interupts to a guest, as well as to
define in which conditions maintenance interrupts are delivered
to the host.
This register doesn't contain any information that we need to
read back (the EOIcount is utterly useless for us).
So let's save ourselves some cycles, and not save it before
writing zero to it.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
ICC_SRE_EL1 is a system register allowing msr/mrs accesses to the
GIC CPU interface for EL1 (guests). Currently we force it to 0, but
for proper GICv3 support we have to allow guests to use it (depending
on their selected virtual GIC model).
So add ICC_SRE_EL1 to the list of saved/restored registers on a
world switch, but actually disallow a guest to change it by only
restoring a fixed, once-initialized value.
This value depends on the GIC model userland has chosen for a guest.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Introduce the support code for emulating a GICv2 on top of GICv3
hardware.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>