tree e3ac79d4ca00d40a358a4a14dc4f62061abb9b9d
parent 0c389d90ebf6ff68f9e19cbb32543084d775d351
author Christoffer Dall <christoffer.dall@linaro.org> 1507728041 +0200
committer Marc Zyngier <marc.zyngier@arm.com> 1521456796 +0000

KVM: arm64: Change 32-bit handling of VM system registers

We currently handle 32-bit accesses to trapped VM system registers using
the 32-bit index into the coproc array on the vcpu structure, which is a
union of the coproc array and the sysreg array.

Since all the 32-bit coproc indices are created to correspond to the
architectural mapping between 64-bit system registers and 32-bit
coprocessor registers, and because the AArch64 system registers are the
double in size of the AArch32 coprocessor registers, we can always find
the system register entry that we must update by dividing the 32-bit
coproc index by 2.

This is going to make our lives much easier when we have to start
accessing system registers that use deferred save/restore and might
have to be read directly from the physical CPU.

Reviewed-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>