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| author |   Marc Zyngier <marc.zyngier@arm.com> | 2016-01-06 13:53:51 +0000 |
|---|---|---|
| committer | Marc Zyngier <marc.zyngier@arm.com> | 2016-02-29 18:34:14 +0000 |
| commit | 96e5e670cc681703c00eaf442c8796da6aa25ca0 (patch) | |
| tree | cd94698dc26b77d6d1ca10c1092ae3822c2987b7 /arch/arm/kvm | |
| parent | ARM: KVM: Add guest entry code (diff) | |
| download | linux-dev-96e5e670cc681703c00eaf442c8796da6aa25ca0.tar.xz linux-dev-96e5e670cc681703c00eaf442c8796da6aa25ca0.zip | |
ARM: KVM: Add VFP lazy save/restore handler
Similar to the arm64 version, add the code that deals with VFP traps,
re-enabling VFP, save/restoring the registers and resuming the guest.
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Diffstat (limited to 'arch/arm/kvm')
| -rw-r--r-- | arch/arm/kvm/hyp/entry.S | 31 |
1 files changed, 31 insertions, 0 deletions
diff --git a/arch/arm/kvm/hyp/entry.S b/arch/arm/kvm/hyp/entry.S index 32f79b090040..21c238871c9e 100644 --- a/arch/arm/kvm/hyp/entry.S +++ b/arch/arm/kvm/hyp/entry.S @@ -66,5 +66,36 @@ ENTRY(__guest_exit) bx lr ENDPROC(__guest_exit) +/* + * If VFPv3 support is not available, then we will not switch the VFP + * registers; however cp10 and cp11 accesses will still trap and fallback + * to the regular coprocessor emulation code, which currently will + * inject an undefined exception to the guest. + */ +#ifdef CONFIG_VFPv3 +ENTRY(__vfp_guest_restore) + push {r3, r4, lr} + + @ NEON/VFP used. Turn on VFP access. + mrc p15, 4, r1, c1, c1, 2 @ HCPTR + bic r1, r1, #(HCPTR_TCP(10) | HCPTR_TCP(11)) + mcr p15, 4, r1, c1, c1, 2 @ HCPTR + isb + + @ Switch VFP/NEON hardware state to the guest's + mov r4, r0 + ldr r0, [r0, #VCPU_HOST_CTXT] + add r0, r0, #CPU_CTXT_VFP + bl __vfp_save_state + add r0, r4, #(VCPU_GUEST_CTXT + CPU_CTXT_VFP) + bl __vfp_restore_state + + pop {r3, r4, lr} + pop {r0, r1, r2} + clrex + eret +ENDPROC(__vfp_guest_restore) +#endif + .popsection |