linux/arch/arm64/kvm/hyp-init.S
Pranavkumar Sawargaonkar f6edbbf36d ARM/ARM64: KVM: Nuke Hyp-mode tlbs before enabling MMU
X-Gene u-boot runs in EL2 mode with MMU enabled hence we might
have stale EL2 tlb enteris when we enable EL2 MMU on each host CPU.

This can happen on any ARM/ARM64 board running bootloader in
Hyp-mode (or EL2-mode) with MMU enabled.

This patch ensures that we flush all Hyp-mode (or EL2-mode) TLBs
on each host CPU before enabling Hyp-mode (or EL2-mode) MMU.

Cc: <stable@vger.kernel.org>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Pranavkumar Sawargaonkar <pranavkumar@linaro.org>
Signed-off-by: Anup Patel <anup.patel@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-08-29 11:53:26 +02:00

121 lines
2.5 KiB
ArmAsm

/*
* Copyright (C) 2012,2013 - ARM Ltd
* Author: Marc Zyngier <marc.zyngier@arm.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License, version 2, as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <linux/linkage.h>
#include <asm/assembler.h>
#include <asm/kvm_arm.h>
#include <asm/kvm_mmu.h>
.text
.pushsection .hyp.idmap.text, "ax"
.align 11
ENTRY(__kvm_hyp_init)
ventry __invalid // Synchronous EL2t
ventry __invalid // IRQ EL2t
ventry __invalid // FIQ EL2t
ventry __invalid // Error EL2t
ventry __invalid // Synchronous EL2h
ventry __invalid // IRQ EL2h
ventry __invalid // FIQ EL2h
ventry __invalid // Error EL2h
ventry __do_hyp_init // Synchronous 64-bit EL1
ventry __invalid // IRQ 64-bit EL1
ventry __invalid // FIQ 64-bit EL1
ventry __invalid // Error 64-bit EL1
ventry __invalid // Synchronous 32-bit EL1
ventry __invalid // IRQ 32-bit EL1
ventry __invalid // FIQ 32-bit EL1
ventry __invalid // Error 32-bit EL1
__invalid:
b .
/*
* x0: HYP boot pgd
* x1: HYP pgd
* x2: HYP stack
* x3: HYP vectors
*/
__do_hyp_init:
msr ttbr0_el2, x0
mrs x4, tcr_el1
ldr x5, =TCR_EL2_MASK
and x4, x4, x5
ldr x5, =TCR_EL2_FLAGS
orr x4, x4, x5
msr tcr_el2, x4
ldr x4, =VTCR_EL2_FLAGS
/*
* Read the PARange bits from ID_AA64MMFR0_EL1 and set the PS bits in
* VTCR_EL2.
*/
mrs x5, ID_AA64MMFR0_EL1
bfi x4, x5, #16, #3
msr vtcr_el2, x4
mrs x4, mair_el1
msr mair_el2, x4
isb
/* Invalidate the stale TLBs from Bootloader */
tlbi alle2
dsb sy
mrs x4, sctlr_el2
and x4, x4, #SCTLR_EL2_EE // preserve endianness of EL2
ldr x5, =SCTLR_EL2_FLAGS
orr x4, x4, x5
msr sctlr_el2, x4
isb
/* MMU is now enabled. Get ready for the trampoline dance */
ldr x4, =TRAMPOLINE_VA
adr x5, target
bfi x4, x5, #0, #PAGE_SHIFT
br x4
target: /* We're now in the trampoline code, switch page tables */
msr ttbr0_el2, x1
isb
/* Invalidate the old TLBs */
tlbi alle2
dsb sy
/* Set the stack and new vectors */
kern_hyp_va x2
mov sp, x2
kern_hyp_va x3
msr vbar_el2, x3
/* Hello, World! */
eret
ENDPROC(__kvm_hyp_init)
.ltorg
.popsection