kvmtool: ARM: Use KVM_ARM_PREFERRED_TARGET vm ioctl to determine target cpu

Instead, of trying out each and every target type we should
use KVM_ARM_PREFERRED_TARGET vm ioctl to determine target type
for KVM ARM/ARM64.

If KVM_ARM_PREFERRED_TARGET vm ioctl fails then we fallback to
old method of trying all known target types.

If KVM_ARM_PREFERRED_TARGET vm ioctl succeeds but the returned
target type is not known to KVMTOOL then we forcefully init
VCPU with target type returned by KVM_ARM_PREFERRED_TARGET vm ioctl.

Signed-off-by: Pranavkumar Sawargaonkar <pranavkumar@linaro.org>
Signed-off-by: Anup Patel <anup.patel@linaro.org>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
kvmtool: ARM64: Add target type potenza for aarch64

The VCPU target type KVM_ARM_TARGET_XGENE_POTENZA is available
in latest Linux-3.16-rcX or higher hence register aarch64 target
type for it.

This patch enables us to run KVMTOOL on X-Gene Potenza host.

Signed-off-by: Pranavkumar Sawargaonkar <pranavkumar@linaro.org>
Signed-off-by: Anup Patel <anup.patel@linaro.org>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
[will: reworded comment for clarity]
Signed-off-by: Will Deacon <will.deacon@arm.com>
kvmtool: Handle exit reason KVM_EXIT_SYSTEM_EVENT

The KVM_EXIT_SYSTEM_EVENT exit reason was added to define
architecture independent system-wide events for a Guest.

Currently, it is used by in-kernel PSCI-0.2 emulation of
KVM ARM/ARM64 to inform user space about PSCI SYSTEM_OFF
or PSCI SYSTEM_RESET request.

For now, we simply treat all system-wide guest events as
shutdown request in KVMTOOL.

Signed-off-by: Pranavkumar Sawargaonkar <pranavkumar@linaro.org>
Signed-off-by: Anup Patel <anup.patel@linaro.org>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
[will: removed useless prints]
Signed-off-by: Will Deacon <will.deacon@arm.com>
kvmtool: ARM/ARM64: Provide PSCI-0.2 to guest when KVM supports it

If in-kernel KVM support PSCI-0.2 emulation then we should set
KVM_ARM_VCPU_PSCI_0_2 feature for each guest VCPU and also
provide "arm,psci-0.2","arm,psci" as PSCI compatible string.

This patch updates kvm_cpu__arch_init() and setup_fdt() as
per above.

Signed-off-by: Pranavkumar Sawargaonkar <pranavkumar@linaro.org>
Signed-off-by: Anup Patel <anup.patel@linaro.org>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>