On Mon, May 14, 2012 at 9:07 AM, Marc Zyngier <marc.zyngier at arm.com> wrote:
> Add some very minimal architected timer related infrastructure.
> For the moment, we just provide empty structures, and enable/disable
> access to the physical timer across world switch.
>
> Signed-off-by: Marc Zyngier <marc.zyngier at arm.com>
> ---
> ?arch/arm/include/asm/kvm_arch_timer.h | ? 27 +++++++++++++++++++++++++++
> ?arch/arm/include/asm/kvm_host.h ? ? ? | ? ?5 +++++
> ?arch/arm/kvm/interrupts.S ? ? ? ? ? ? | ? 23 ++++++++++++++++++++++-
> ?3 files changed, 54 insertions(+), 1 deletions(-)
> ?create mode 100644 arch/arm/include/asm/kvm_arch_timer.h
>
> diff --git a/arch/arm/include/asm/kvm_arch_timer.h b/arch/arm/include/asm/kvm_arch_timer.h
> new file mode 100644
> index 0000000..491e336
> --- /dev/null
> +++ b/arch/arm/include/asm/kvm_arch_timer.h
> @@ -0,0 +1,27 @@
> +#ifndef __ASM_ARM_KVM_ARCH_TIMER_H
> +#define __ASM_ARM_KVM_ARCH_TIMER_H
> +
> +struct arch_timer_kvm {
> +};
> +
> +struct arch_timer_cpu {
> +};
> +
> +#ifndef CONFIG_KVM_ARM_TIMER
> +static inline int kvm_timer_hyp_init(void)
> +{
> + ? ? ? return 0;
> +};
> +
> +static inline int kvm_timer_init(struct kvm *kvm)
> +{
> + ? ? ? return 0;
> +}
> +
> +static inline void kvm_timer_vcpu_init(struct kvm_vcpu *vcpu) {}
> +static inline void kvm_timer_sync_to_cpu(struct kvm_vcpu *vcpu) {}
> +static inline void kvm_timer_sync_from_cpu(struct kvm_vcpu *vcpu) {}
> +static inline void kvm_timer_vcpu_terminate(struct kvm_vcpu *vcpu) {}
> +#endif
> +
> +#endif
> diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
> index ffef12b..44ce5b5 100644
> --- a/arch/arm/include/asm/kvm_host.h
> +++ b/arch/arm/include/asm/kvm_host.h
> @@ -23,6 +23,7 @@
> ?#define KVM_COALESCED_MMIO_PAGE_OFFSET 1
>
> ?#include <asm/kvm_vgic.h>
> +#include <asm/kvm_arch_timer.h>
>
> ?/* We don't currently support large pages. */
> ?#define KVM_HPAGE_GFN_SHIFT(x) 0
> @@ -45,6 +46,9 @@ struct kvm_arch {
>
> ? ? ? ?/* Interrupt controller */
> ? ? ? ?struct vgic_dist ? ? ? ?vgic;
> +
> + ? ? ? /* Timer */
> + ? ? ? struct arch_timer_kvm ? timer;
> ?};
>
> ?#define EXCEPTION_NONE ? ? ?0
> @@ -111,6 +115,7 @@ struct kvm_vcpu_arch {
> ? ? ? ?u32 irq_lines; ? ? ? ? ?/* IRQ and FIQ levels */
> ? ? ? ?u32 wait_for_interrupts;
> ? ? ? ?struct vgic_cpu vgic_cpu;
> + ? ? ? struct arch_timer_cpu timer_cpu;
> ?};
>
> ?struct kvm_vm_stat {
> diff --git a/arch/arm/kvm/interrupts.S b/arch/arm/kvm/interrupts.S
> index 541532b..56a65c4 100644
> --- a/arch/arm/kvm/interrupts.S
> +++ b/arch/arm/kvm/interrupts.S
> @@ -311,7 +311,26 @@ ENTRY(__kvm_flush_vm_context)
> ?2:
> ?#endif
> ?.endm
> -
> +
> +#define PL1P_ENABLE ? ?3
> +#define PL1P_DISABLE ? 3
nit: this is weird, I think it should be PL1P_MASK and just have a comment below
> +
> +.macro save_timer_state ? ? ? ?vcpup
> + ? ? ? @ Allow physical timer access for the host
> + ? ? ? mrc ? ? p15, 4, r2, c14, c1, 0 ?@ CNTHCTL
> + ? ? ? orr ? ? r2, r2, #PL1P_ENABLE
> + ? ? ? mcr ? ? p15, 4, r2, c14, c1, 0 ?@ CNTHCTL
> +.endm
> +
> +.macro restore_timer_state vcpup
> + ? ? ? @ Disallow physical timer access for the guest
> + ? ? ? mrc ? ? p15, 4, r2, c14, c1, 0 ?@ CNTHCTL
> + ? ? ? bic ? ? r2, r2, #PL1P_DISABLE
> + ? ? ? mcr ? ? p15, 4, r2, c14, c1, 0 ?@ CNTHCTL
> +
> + ? ? ? isb
> +.endm
nit: consider using the commenting format from the corresponding vgic
macros with a @vcpup parameter description for consistency.
> +
> ?/* Configures the HSTR (Hyp System Trap Register) on entry/return
> ?* (hardware reset value is 0) */
> ?.macro set_hstr entry
> @@ -357,6 +376,7 @@ ENTRY(__kvm_vcpu_run)
> ? ? ? ?store_mode_state sp, fiq
>
> ? ? ? ?restore_vgic_state r0
> + ? ? ? restore_timer_state r0
>
> ? ? ? ?@ Store hardware CP15 state and load guest state
> ? ? ? ?read_cp15_state
> @@ -443,6 +463,7 @@ __kvm_vcpu_return:
> ? ? ? ?read_cp15_state 1, r1
> ? ? ? ?write_cp15_state
>
> + ? ? ? save_timer_state r1
> ? ? ? ?save_vgic_state r1
>
> ? ? ? ?load_mode_state sp, fiq
> --
> 1.7.7.1
>
looks ok to me.
-Christoffer
