[PATCH v3 11/32] arm64: KVM: CPU specific system registers handling

[Will Deacon]

On Mon, Apr 08, 2013 at 05:17:13PM +0100, Marc Zyngier wrote:
> Add the support code for CPU specific system registers. Not much
> here yet.
> 
> Reviewed-by: Christopher Covington <cov at codeaurora.org>
> Signed-off-by: Marc Zyngier <marc.zyngier at arm.com>
> ---
>  arch/arm64/kvm/sys_regs_generic_v8.c | 85 ++++++++++++++++++++++++++++++++++++
>  1 file changed, 85 insertions(+)
>  create mode 100644 arch/arm64/kvm/sys_regs_generic_v8.c
> 
> diff --git a/arch/arm64/kvm/sys_regs_generic_v8.c b/arch/arm64/kvm/sys_regs_generic_v8.c
> new file mode 100644
> index 0000000..d4e8039
> --- /dev/null
> +++ b/arch/arm64/kvm/sys_regs_generic_v8.c
> @@ -0,0 +1,85 @@
> +/*
> + * Copyright (C) 2012,2013 - ARM Ltd
> + * Author: Marc Zyngier <marc.zyngier at arm.com>
> + *
> + * Based on arch/arm/kvm/coproc_a15.c:
> + * Copyright (C) 2012 - Virtual Open Systems and Columbia University
> + * Authors: Rusty Russell <rusty at rustcorp.au>
> + *          Christoffer Dall <c.dall at 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/kvm_host.h>
> +#include <asm/cputype.h>
> +#include <asm/kvm_arm.h>
> +#include <asm/kvm_asm.h>
> +#include <asm/kvm_host.h>
> +#include <asm/kvm_emulate.h>
> +#include <asm/kvm_coproc.h>
> +#include <linux/init.h>
> +
> +#include "sys_regs.h"
> +
> +static bool access_actlr(struct kvm_vcpu *vcpu,
> +			 const struct sys_reg_params *p,
> +			 const struct sys_reg_desc *r)
> +{
> +	if (p->is_write)
> +		return ignore_write(vcpu, p);
> +
> +	*vcpu_reg(vcpu, p->Rt) = vcpu_sys_reg(vcpu, ACTLR_EL1);
> +	return true;
> +}
> +
> +static void reset_actlr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r)
> +{
> +	u64 actlr;
> +
> +	asm volatile("mrs %0, actlr_el1\n" : "=r" (actlr));
> +	vcpu_sys_reg(vcpu, ACTLR_EL1) = actlr;
> +}

Do we actually need this? If so, there are likely other registers (things
like the ectlr) that should be considered too.

Will