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KVM: arm: Enable emulation of the physical timer

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Set the handlers to emulate read and write operations for CNTP_CTL,
CNTP_CVAL and CNTP_TVAL registers in such a way that VMs can use the
physical timer.

Signed-off-by: Jérémy Fanguède <j.fanguede@virtualopensystems.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
This commit is contained in:
Jérémy Fanguède 2018-02-13 11:41:16 +01:00 committed by Christoffer Dall
parent eac137b4a9
commit b9fb17395b
1 changed files with 61 additions and 0 deletions
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61
arch/arm/kvm/coproc.c
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@ -270,6 +270,60 @@ static bool access_gic_sre(struct kvm_vcpu *vcpu,
return true;
}
static bool access_cntp_tval(struct kvm_vcpu *vcpu,
const struct coproc_params *p,
const struct coproc_reg *r)
{
u64 now = kvm_phys_timer_read();
u64 val;
if (p->is_write) {
val = *vcpu_reg(vcpu, p->Rt1);
kvm_arm_timer_set_reg(vcpu, KVM_REG_ARM_PTIMER_CVAL, val + now);
} else {
val = kvm_arm_timer_get_reg(vcpu, KVM_REG_ARM_PTIMER_CVAL);
*vcpu_reg(vcpu, p->Rt1) = val - now;
}
return true;
}
static bool access_cntp_ctl(struct kvm_vcpu *vcpu,
const struct coproc_params *p,
const struct coproc_reg *r)
{
u32 val;
if (p->is_write) {
val = *vcpu_reg(vcpu, p->Rt1);
kvm_arm_timer_set_reg(vcpu, KVM_REG_ARM_PTIMER_CTL, val);
} else {
val = kvm_arm_timer_get_reg(vcpu, KVM_REG_ARM_PTIMER_CTL);
*vcpu_reg(vcpu, p->Rt1) = val;
}
return true;
}
static bool access_cntp_cval(struct kvm_vcpu *vcpu,
const struct coproc_params *p,
const struct coproc_reg *r)
{
u64 val;
if (p->is_write) {
val = (u64)*vcpu_reg(vcpu, p->Rt2) << 32;
val |= *vcpu_reg(vcpu, p->Rt1);
kvm_arm_timer_set_reg(vcpu, KVM_REG_ARM_PTIMER_CVAL, val);
} else {
val = kvm_arm_timer_get_reg(vcpu, KVM_REG_ARM_PTIMER_CVAL);
*vcpu_reg(vcpu, p->Rt1) = val;
*vcpu_reg(vcpu, p->Rt2) = val >> 32;
}
return true;
}
/*
* We could trap ID_DFR0 and tell the guest we don't support performance
* monitoring. Unfortunately the patch to make the kernel check ID_DFR0 was
@ -423,10 +477,17 @@ static const struct coproc_reg cp15_regs[] = {
{ CRn(13), CRm( 0), Op1( 0), Op2( 4), is32,
NULL, reset_unknown, c13_TID_PRIV },
/* CNTP */
{ CRm64(14), Op1( 2), is64, access_cntp_cval},
/* CNTKCTL: swapped by interrupt.S. */
{ CRn(14), CRm( 1), Op1( 0), Op2( 0), is32,
NULL, reset_val, c14_CNTKCTL, 0x00000000 },
/* CNTP */
{ CRn(14), CRm( 2), Op1( 0), Op2( 0), is32, access_cntp_tval },
{ CRn(14), CRm( 2), Op1( 0), Op2( 1), is32, access_cntp_ctl },
/* The Configuration Base Address Register. */
{ CRn(15), CRm( 0), Op1( 4), Op2( 0), is32, access_cbar},
};