On Mon, Jul 06, 2015 at 10:17:43AM +0800, shannon.zhao@xxxxxxxxxx wrote:
> From: Shannon Zhao <shannon.zhao@xxxxxxxxxx>
>
> Since the reset value of PMOVSSET_EL0 and PMOVSCLR_EL0 is UNKNOWN, use
> reset_unknown for its reset handler. Add access handler which emulates
> writing and reading PMOVSSET_EL0 or PMOVSCLR_EL0 register.
>
> Signed-off-by: Shannon Zhao <shannon.zhao@xxxxxxxxxx>
> ---
> arch/arm64/kvm/sys_regs.c | 30 ++++++++++++++++++++++++++++--
> 1 file changed, 28 insertions(+), 2 deletions(-)
>
> diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
> index cbc07b8..ec80937 100644
> --- a/arch/arm64/kvm/sys_regs.c
> +++ b/arch/arm64/kvm/sys_regs.c
> @@ -496,6 +496,32 @@ static bool access_pmintenclr(struct kvm_vcpu *vcpu,
> return true;
> }
>
> +/* PMOVSSET_EL0 accessor. */
> +static bool access_pmovsset(struct kvm_vcpu *vcpu,
> + const struct sys_reg_params *p,
> + const struct sys_reg_desc *r)
> +{
> + if (p->is_write)
> + vcpu->arch.pmu.overflow_status |= *vcpu_reg(vcpu, p->Rt);
> + else
> + *vcpu_reg(vcpu, p->Rt) = vcpu->arch.pmu.overflow_status;
if you store this state in PMOVSSET_EL0 you get VM migration
save/restore support for (almost) free.
-Christoffer
> +
> + return true;
> +}
> +
> +/* PMOVSCLR_EL0 accessor. */
> +static bool access_pmovsclr(struct kvm_vcpu *vcpu,
> + const struct sys_reg_params *p,
> + const struct sys_reg_desc *r)
> +{
> + if (p->is_write)
> + vcpu->arch.pmu.overflow_status &= (~*vcpu_reg(vcpu, p->Rt));
> + else
> + *vcpu_reg(vcpu, p->Rt) = vcpu->arch.pmu.overflow_status;
> +
> + return true;
> +}
> +
> /* Silly macro to expand the DBG{BCR,BVR,WVR,WCR}n_EL1 registers in one go */
> #define DBG_BCR_BVR_WCR_WVR_EL1(n) \
> /* DBGBVRn_EL1 */ \
> @@ -696,7 +722,7 @@ static const struct sys_reg_desc sys_reg_descs[] = {
> access_pmcntenclr, reset_unknown, PMCNTENCLR_EL0 },
> /* PMOVSCLR_EL0 */
> { Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1100), Op2(0b011),
> - trap_raz_wi },
> + access_pmovsclr, reset_unknown, PMOVSCLR_EL0 },
> /* PMSWINC_EL0 */
> { Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1100), Op2(0b100),
> trap_raz_wi },
> @@ -723,7 +749,7 @@ static const struct sys_reg_desc sys_reg_descs[] = {
> trap_raz_wi },
> /* PMOVSSET_EL0 */
> { Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1110), Op2(0b011),
> - trap_raz_wi },
> + access_pmovsset, reset_unknown, PMOVSSET_EL0 },
>
> /* TPIDR_EL0 */
> { Op0(0b11), Op1(0b011), CRn(0b1101), CRm(0b0000), Op2(0b010),
> --
> 2.1.0
>
--
To unsubscribe from this list: send the line "unsubscribe kvm" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
