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git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
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linux
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>
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arch/arm/kvm/hyp/entry.S
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arch/arm/kvm/hyp/entry.S
···
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bx lr
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ENDPROC(__guest_exit)
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/*
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* If VFPv3 support is not available, then we will not switch the VFP
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* registers; however cp10 and cp11 accesses will still trap and fallback
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* to the regular coprocessor emulation code, which currently will
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* inject an undefined exception to the guest.
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*/
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#ifdef CONFIG_VFPv3
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ENTRY(__vfp_guest_restore)
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push {r3, r4, lr}
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@ NEON/VFP used. Turn on VFP access.
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mrc p15, 4, r1, c1, c1, 2 @ HCPTR
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bic r1, r1, #(HCPTR_TCP(10) | HCPTR_TCP(11))
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mcr p15, 4, r1, c1, c1, 2 @ HCPTR
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isb
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@ Switch VFP/NEON hardware state to the guest's
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mov r4, r0
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ldr r0, [r0, #VCPU_HOST_CTXT]
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add r0, r0, #CPU_CTXT_VFP
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bl __vfp_save_state
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add r0, r4, #(VCPU_GUEST_CTXT + CPU_CTXT_VFP)
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bl __vfp_restore_state
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pop {r3, r4, lr}
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pop {r0, r1, r2}
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clrex
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eret
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ENDPROC(__vfp_guest_restore)
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#endif
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.popsection
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