arm64: KVM: Implement HVC_SOFT_RESTART in the init code

Another missing stub hypercall is HVC_SOFT_RESTART. It turns out
that it is pretty easy to implement in terms of HVC_RESET_VECTORS
(since it needs to turn the MMU off).

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
This commit is contained in:
Marc Zyngier 2017-04-03 19:37:44 +01:00 committed by Christoffer Dall
parent 4adb1341c7
commit 506c372ac4

View file

@ -129,21 +129,36 @@ ENTRY(__kvm_handle_stub_hvc)
mrs x0, vbar_el2
b exit
1: cmp x0, #HVC_SOFT_RESTART
b.ne 1f
/* This is where we're about to jump, staying at EL2 */
msr elr_el2, x1
mov x0, #(PSR_F_BIT | PSR_I_BIT | PSR_A_BIT | PSR_D_BIT | PSR_MODE_EL2h)
msr spsr_el2, x0
/* Shuffle the arguments, and don't come back */
mov x0, x2
mov x1, x3
mov x2, x4
b reset
1: cmp x0, #HVC_RESET_VECTORS
b.ne 1f
reset:
/*
* Reset kvm back to the hyp stub.
* Reset kvm back to the hyp stub. Do not clobber x0-x4 in
* case we coming via HVC_SOFT_RESTART.
*/
/* We're now in idmap, disable MMU */
mrs x0, sctlr_el2
ldr x1, =SCTLR_ELx_FLAGS
bic x0, x0, x1 // Clear SCTL_M and etc
msr sctlr_el2, x0
mrs x5, sctlr_el2
ldr x6, =SCTLR_ELx_FLAGS
bic x5, x5, x6 // Clear SCTL_M and etc
msr sctlr_el2, x5
isb
/* Install stub vectors */
adr_l x0, __hyp_stub_vectors
msr vbar_el2, x0
adr_l x5, __hyp_stub_vectors
msr vbar_el2, x5
b exit
1: /* Bad stub call */