linux-stable/arch/arm64/kvm/reset.c
Marc Zyngier 0d854a60b1 arm64: KVM: enable initialization of a 32bit vcpu
Wire the init of a 32bit vcpu by allowing 32bit modes in pstate,
and providing sensible defaults out of reset state.

This feature is of course conditioned by the presence of 32bit
capability on the physical CPU, and is checked by the KVM_CAP_ARM_EL1_32BIT
capability.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2013-06-12 16:42:18 +01:00

112 lines
2.6 KiB
C

/*
* Copyright (C) 2012,2013 - ARM Ltd
* Author: Marc Zyngier <marc.zyngier@arm.com>
*
* Derived from arch/arm/kvm/reset.c
* Copyright (C) 2012 - Virtual Open Systems and Columbia University
* Author: Christoffer Dall <c.dall@virtualopensystems.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/errno.h>
#include <linux/kvm_host.h>
#include <linux/kvm.h>
#include <kvm/arm_arch_timer.h>
#include <asm/cputype.h>
#include <asm/ptrace.h>
#include <asm/kvm_arm.h>
#include <asm/kvm_coproc.h>
/*
* ARMv8 Reset Values
*/
static const struct kvm_regs default_regs_reset = {
.regs.pstate = (PSR_MODE_EL1h | PSR_A_BIT | PSR_I_BIT |
PSR_F_BIT | PSR_D_BIT),
};
static const struct kvm_regs default_regs_reset32 = {
.regs.pstate = (COMPAT_PSR_MODE_SVC | COMPAT_PSR_A_BIT |
COMPAT_PSR_I_BIT | COMPAT_PSR_F_BIT),
};
static const struct kvm_irq_level default_vtimer_irq = {
.irq = 27,
.level = 1,
};
static bool cpu_has_32bit_el1(void)
{
u64 pfr0;
pfr0 = read_cpuid(ID_AA64PFR0_EL1);
return !!(pfr0 & 0x20);
}
int kvm_arch_dev_ioctl_check_extension(long ext)
{
int r;
switch (ext) {
case KVM_CAP_ARM_EL1_32BIT:
r = cpu_has_32bit_el1();
break;
default:
r = 0;
}
return r;
}
/**
* kvm_reset_vcpu - sets core registers and sys_regs to reset value
* @vcpu: The VCPU pointer
*
* This function finds the right table above and sets the registers on
* the virtual CPU struct to their architectually defined reset
* values.
*/
int kvm_reset_vcpu(struct kvm_vcpu *vcpu)
{
const struct kvm_irq_level *cpu_vtimer_irq;
const struct kvm_regs *cpu_reset;
switch (vcpu->arch.target) {
default:
if (test_bit(KVM_ARM_VCPU_EL1_32BIT, vcpu->arch.features)) {
if (!cpu_has_32bit_el1())
return -EINVAL;
cpu_reset = &default_regs_reset32;
vcpu->arch.hcr_el2 &= ~HCR_RW;
} else {
cpu_reset = &default_regs_reset;
}
cpu_vtimer_irq = &default_vtimer_irq;
break;
}
/* Reset core registers */
memcpy(vcpu_gp_regs(vcpu), cpu_reset, sizeof(*cpu_reset));
/* Reset system registers */
kvm_reset_sys_regs(vcpu);
/* Reset timer */
kvm_timer_vcpu_reset(vcpu, cpu_vtimer_irq);
return 0;
}