[v3,4/8] RISC-V: KVM: Initial skeletal support for AIA

Message ID 20230403093310.2271142-5-apatel@ventanamicro.com
State New
Headers
Series RISC-V KVM virtualize AIA CSRs |

Commit Message

Anup Patel April 3, 2023, 9:33 a.m. UTC
  To incrementally implement AIA support, we first add minimal skeletal
support which only compiles and detects AIA hardware support at the
boot-time but does not provide any functionality.

Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
---
 arch/riscv/include/asm/hwcap.h    |   6 ++
 arch/riscv/include/asm/kvm_aia.h  | 109 ++++++++++++++++++++++++++++++
 arch/riscv/include/asm/kvm_host.h |   7 ++
 arch/riscv/kvm/Makefile           |   1 +
 arch/riscv/kvm/aia.c              |  66 ++++++++++++++++++
 arch/riscv/kvm/main.c             |  22 +++++-
 arch/riscv/kvm/vcpu.c             |  40 ++++++++++-
 arch/riscv/kvm/vcpu_insn.c        |   1 +
 arch/riscv/kvm/vm.c               |   4 ++
 9 files changed, 252 insertions(+), 4 deletions(-)
 create mode 100644 arch/riscv/include/asm/kvm_aia.h
 create mode 100644 arch/riscv/kvm/aia.c
  

Comments

Andrew Jones April 3, 2023, noon UTC | #1
On Mon, Apr 03, 2023 at 03:03:06PM +0530, Anup Patel wrote:
> To incrementally implement AIA support, we first add minimal skeletal
> support which only compiles and detects AIA hardware support at the
> boot-time but does not provide any functionality.
> 
> Signed-off-by: Anup Patel <apatel@ventanamicro.com>
> Reviewed-by: Atish Patra <atishp@rivosinc.com>
> ---
>  arch/riscv/include/asm/hwcap.h    |   6 ++
>  arch/riscv/include/asm/kvm_aia.h  | 109 ++++++++++++++++++++++++++++++
>  arch/riscv/include/asm/kvm_host.h |   7 ++
>  arch/riscv/kvm/Makefile           |   1 +
>  arch/riscv/kvm/aia.c              |  66 ++++++++++++++++++
>  arch/riscv/kvm/main.c             |  22 +++++-
>  arch/riscv/kvm/vcpu.c             |  40 ++++++++++-
>  arch/riscv/kvm/vcpu_insn.c        |   1 +
>  arch/riscv/kvm/vm.c               |   4 ++
>  9 files changed, 252 insertions(+), 4 deletions(-)
>  create mode 100644 arch/riscv/include/asm/kvm_aia.h
>  create mode 100644 arch/riscv/kvm/aia.c
>

Reviewed-by: Andrew Jones <ajones@ventanamicro.com>

Thanks,
drew
  
Atish Patra April 3, 2023, 11:49 p.m. UTC | #2
On Mon, Apr 3, 2023 at 3:03 PM Anup Patel <apatel@ventanamicro.com> wrote:
>
> To incrementally implement AIA support, we first add minimal skeletal
> support which only compiles and detects AIA hardware support at the
> boot-time but does not provide any functionality.
>
> Signed-off-by: Anup Patel <apatel@ventanamicro.com>
> Reviewed-by: Atish Patra <atishp@rivosinc.com>
> ---
>  arch/riscv/include/asm/hwcap.h    |   6 ++
>  arch/riscv/include/asm/kvm_aia.h  | 109 ++++++++++++++++++++++++++++++
>  arch/riscv/include/asm/kvm_host.h |   7 ++
>  arch/riscv/kvm/Makefile           |   1 +
>  arch/riscv/kvm/aia.c              |  66 ++++++++++++++++++
>  arch/riscv/kvm/main.c             |  22 +++++-
>  arch/riscv/kvm/vcpu.c             |  40 ++++++++++-
>  arch/riscv/kvm/vcpu_insn.c        |   1 +
>  arch/riscv/kvm/vm.c               |   4 ++
>  9 files changed, 252 insertions(+), 4 deletions(-)
>  create mode 100644 arch/riscv/include/asm/kvm_aia.h
>  create mode 100644 arch/riscv/kvm/aia.c
>
> diff --git a/arch/riscv/include/asm/hwcap.h b/arch/riscv/include/asm/hwcap.h
> index 9c8ae4399565..8087e11a5cf8 100644
> --- a/arch/riscv/include/asm/hwcap.h
> +++ b/arch/riscv/include/asm/hwcap.h
> @@ -48,6 +48,12 @@
>  #define RISCV_ISA_EXT_MAX              64
>  #define RISCV_ISA_EXT_NAME_LEN_MAX     32
>
> +#ifdef CONFIG_RISCV_M_MODE
> +#define RISCV_ISA_EXT_SxAIA            RISCV_ISA_EXT_SMAIA
> +#else
> +#define RISCV_ISA_EXT_SxAIA            RISCV_ISA_EXT_SSAIA
> +#endif
> +
>  #ifndef __ASSEMBLY__
>
>  #include <linux/jump_label.h>
> diff --git a/arch/riscv/include/asm/kvm_aia.h b/arch/riscv/include/asm/kvm_aia.h
> new file mode 100644
> index 000000000000..258a835d4c32
> --- /dev/null
> +++ b/arch/riscv/include/asm/kvm_aia.h
> @@ -0,0 +1,109 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +/*
> + * Copyright (C) 2021 Western Digital Corporation or its affiliates.
> + * Copyright (C) 2022 Ventana Micro Systems Inc.
> + *
> + * Authors:
> + *     Anup Patel <apatel@ventanamicro.com>
> + */
> +
> +#ifndef __KVM_RISCV_AIA_H
> +#define __KVM_RISCV_AIA_H
> +
> +#include <linux/jump_label.h>
> +#include <linux/kvm_types.h>
> +
> +struct kvm_aia {
> +       /* In-kernel irqchip created */
> +       bool            in_kernel;
> +
> +       /* In-kernel irqchip initialized */
> +       bool            initialized;
> +};
> +
> +struct kvm_vcpu_aia {
> +};
> +
> +#define kvm_riscv_aia_initialized(k)   ((k)->arch.aia.initialized)
> +
> +#define irqchip_in_kernel(k)           ((k)->arch.aia.in_kernel)
> +
> +DECLARE_STATIC_KEY_FALSE(kvm_riscv_aia_available);
> +#define kvm_riscv_aia_available() \
> +       static_branch_unlikely(&kvm_riscv_aia_available)
> +
> +static inline void kvm_riscv_vcpu_aia_flush_interrupts(struct kvm_vcpu *vcpu)
> +{
> +}
> +
> +static inline void kvm_riscv_vcpu_aia_sync_interrupts(struct kvm_vcpu *vcpu)
> +{
> +}
> +
> +static inline bool kvm_riscv_vcpu_aia_has_interrupts(struct kvm_vcpu *vcpu,
> +                                                    u64 mask)
> +{
> +       return false;
> +}
> +
> +static inline void kvm_riscv_vcpu_aia_update_hvip(struct kvm_vcpu *vcpu)
> +{
> +}
> +
> +static inline void kvm_riscv_vcpu_aia_load(struct kvm_vcpu *vcpu, int cpu)
> +{
> +}
> +
> +static inline void kvm_riscv_vcpu_aia_put(struct kvm_vcpu *vcpu)
> +{
> +}
> +
> +static inline int kvm_riscv_vcpu_aia_get_csr(struct kvm_vcpu *vcpu,
> +                                            unsigned long reg_num,
> +                                            unsigned long *out_val)
> +{
> +       *out_val = 0;
> +       return 0;
> +}
> +
> +static inline int kvm_riscv_vcpu_aia_set_csr(struct kvm_vcpu *vcpu,
> +                                            unsigned long reg_num,
> +                                            unsigned long val)
> +{
> +       return 0;
> +}
> +
> +#define KVM_RISCV_VCPU_AIA_CSR_FUNCS
> +
> +static inline int kvm_riscv_vcpu_aia_update(struct kvm_vcpu *vcpu)
> +{
> +       return 1;
> +}
> +
> +static inline void kvm_riscv_vcpu_aia_reset(struct kvm_vcpu *vcpu)
> +{
> +}
> +
> +static inline int kvm_riscv_vcpu_aia_init(struct kvm_vcpu *vcpu)
> +{
> +       return 0;
> +}
> +
> +static inline void kvm_riscv_vcpu_aia_deinit(struct kvm_vcpu *vcpu)
> +{
> +}
> +
> +static inline void kvm_riscv_aia_init_vm(struct kvm *kvm)
> +{
> +}
> +
> +static inline void kvm_riscv_aia_destroy_vm(struct kvm *kvm)
> +{
> +}
> +
> +void kvm_riscv_aia_enable(void);
> +void kvm_riscv_aia_disable(void);
> +int kvm_riscv_aia_init(void);
> +void kvm_riscv_aia_exit(void);
> +
> +#endif
> diff --git a/arch/riscv/include/asm/kvm_host.h b/arch/riscv/include/asm/kvm_host.h
> index cc7da66ee0c0..3157cf748df1 100644
> --- a/arch/riscv/include/asm/kvm_host.h
> +++ b/arch/riscv/include/asm/kvm_host.h
> @@ -14,6 +14,7 @@
>  #include <linux/kvm_types.h>
>  #include <linux/spinlock.h>
>  #include <asm/hwcap.h>
> +#include <asm/kvm_aia.h>
>  #include <asm/kvm_vcpu_fp.h>
>  #include <asm/kvm_vcpu_insn.h>
>  #include <asm/kvm_vcpu_sbi.h>
> @@ -94,6 +95,9 @@ struct kvm_arch {
>
>         /* Guest Timer */
>         struct kvm_guest_timer timer;
> +
> +       /* AIA Guest/VM context */
> +       struct kvm_aia aia;
>  };
>
>  struct kvm_cpu_trap {
> @@ -221,6 +225,9 @@ struct kvm_vcpu_arch {
>         /* SBI context */
>         struct kvm_vcpu_sbi_context sbi_context;
>
> +       /* AIA VCPU context */
> +       struct kvm_vcpu_aia aia_context;
> +
>         /* Cache pages needed to program page tables with spinlock held */
>         struct kvm_mmu_memory_cache mmu_page_cache;
>
> diff --git a/arch/riscv/kvm/Makefile b/arch/riscv/kvm/Makefile
> index 278e97c06e0a..8031b8912a0d 100644
> --- a/arch/riscv/kvm/Makefile
> +++ b/arch/riscv/kvm/Makefile
> @@ -26,3 +26,4 @@ kvm-y += vcpu_sbi_replace.o
>  kvm-y += vcpu_sbi_hsm.o
>  kvm-y += vcpu_timer.o
>  kvm-$(CONFIG_RISCV_PMU_SBI) += vcpu_pmu.o vcpu_sbi_pmu.o
> +kvm-y += aia.o
> diff --git a/arch/riscv/kvm/aia.c b/arch/riscv/kvm/aia.c
> new file mode 100644
> index 000000000000..7a633331cd3e
> --- /dev/null
> +++ b/arch/riscv/kvm/aia.c
> @@ -0,0 +1,66 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2021 Western Digital Corporation or its affiliates.
> + * Copyright (C) 2022 Ventana Micro Systems Inc.
> + *
> + * Authors:
> + *     Anup Patel <apatel@ventanamicro.com>
> + */
> +
> +#include <linux/kvm_host.h>
> +#include <asm/hwcap.h>
> +
> +DEFINE_STATIC_KEY_FALSE(kvm_riscv_aia_available);
> +
> +static void aia_set_hvictl(bool ext_irq_pending)
> +{
> +       unsigned long hvictl;
> +
> +       /*
> +        * HVICTL.IID == 9 and HVICTL.IPRIO == 0 represents
> +        * no interrupt in HVICTL.
> +        */
> +
> +       hvictl = (IRQ_S_EXT << HVICTL_IID_SHIFT) & HVICTL_IID;
> +       hvictl |= ext_irq_pending;
> +       csr_write(CSR_HVICTL, hvictl);
> +}
> +
> +void kvm_riscv_aia_enable(void)
> +{
> +       if (!kvm_riscv_aia_available())
> +               return;
> +
> +       aia_set_hvictl(false);
> +       csr_write(CSR_HVIPRIO1, 0x0);
> +       csr_write(CSR_HVIPRIO2, 0x0);
> +#ifdef CONFIG_32BIT
> +       csr_write(CSR_HVIPH, 0x0);
> +       csr_write(CSR_HIDELEGH, 0x0);
> +       csr_write(CSR_HVIPRIO1H, 0x0);
> +       csr_write(CSR_HVIPRIO2H, 0x0);
> +#endif
> +}
> +
> +void kvm_riscv_aia_disable(void)
> +{
> +       if (!kvm_riscv_aia_available())
> +               return;
> +
> +       aia_set_hvictl(false);
> +}
> +
> +int kvm_riscv_aia_init(void)
> +{
> +       if (!riscv_isa_extension_available(NULL, SxAIA))
> +               return -ENODEV;
> +
> +       /* Enable KVM AIA support */
> +       static_branch_enable(&kvm_riscv_aia_available);
> +
> +       return 0;
> +}
> +
> +void kvm_riscv_aia_exit(void)
> +{
> +}
> diff --git a/arch/riscv/kvm/main.c b/arch/riscv/kvm/main.c
> index 41ad7639a17b..6396352b4e4d 100644
> --- a/arch/riscv/kvm/main.c
> +++ b/arch/riscv/kvm/main.c
> @@ -44,11 +44,15 @@ int kvm_arch_hardware_enable(void)
>
>         csr_write(CSR_HVIP, 0);
>
> +       kvm_riscv_aia_enable();
> +
>         return 0;
>  }
>
>  void kvm_arch_hardware_disable(void)
>  {
> +       kvm_riscv_aia_disable();
> +
>         /*
>          * After clearing the hideleg CSR, the host kernel will receive
>          * spurious interrupts if hvip CSR has pending interrupts and the
> @@ -63,6 +67,7 @@ void kvm_arch_hardware_disable(void)
>
>  static int __init riscv_kvm_init(void)
>  {
> +       int rc;
>         const char *str;
>
>         if (!riscv_isa_extension_available(NULL, h)) {
> @@ -84,6 +89,10 @@ static int __init riscv_kvm_init(void)
>
>         kvm_riscv_gstage_vmid_detect();
>
> +       rc = kvm_riscv_aia_init();
> +       if (rc && rc != -ENODEV)
> +               return rc;
> +
>         kvm_info("hypervisor extension available\n");
>
>         switch (kvm_riscv_gstage_mode()) {
> @@ -106,12 +115,23 @@ static int __init riscv_kvm_init(void)
>
>         kvm_info("VMID %ld bits available\n", kvm_riscv_gstage_vmid_bits());
>
> -       return kvm_init(sizeof(struct kvm_vcpu), 0, THIS_MODULE);
> +       if (kvm_riscv_aia_available())
> +               kvm_info("AIA available\n");
> +
> +       rc = kvm_init(sizeof(struct kvm_vcpu), 0, THIS_MODULE);
> +       if (rc) {
> +               kvm_riscv_aia_exit();
> +               return rc;
> +       }
> +
> +       return 0;
>  }
>  module_init(riscv_kvm_init);
>
>  static void __exit riscv_kvm_exit(void)
>  {
> +       kvm_riscv_aia_exit();
> +
>         kvm_exit();
>  }
>  module_exit(riscv_kvm_exit);
> diff --git a/arch/riscv/kvm/vcpu.c b/arch/riscv/kvm/vcpu.c
> index 02b49cb94561..1fd54ec15622 100644
> --- a/arch/riscv/kvm/vcpu.c
> +++ b/arch/riscv/kvm/vcpu.c
> @@ -137,6 +137,8 @@ static void kvm_riscv_reset_vcpu(struct kvm_vcpu *vcpu)
>
>         kvm_riscv_vcpu_timer_reset(vcpu);
>
> +       kvm_riscv_vcpu_aia_reset(vcpu);
> +
>         WRITE_ONCE(vcpu->arch.irqs_pending, 0);
>         WRITE_ONCE(vcpu->arch.irqs_pending_mask, 0);
>
> @@ -159,6 +161,7 @@ int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
>
>  int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
>  {
> +       int rc;
>         struct kvm_cpu_context *cntx;
>         struct kvm_vcpu_csr *reset_csr = &vcpu->arch.guest_reset_csr;
>         unsigned long host_isa, i;
> @@ -201,6 +204,11 @@ int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
>         /* setup performance monitoring */
>         kvm_riscv_vcpu_pmu_init(vcpu);
>
> +       /* Setup VCPU AIA */
> +       rc = kvm_riscv_vcpu_aia_init(vcpu);
> +       if (rc)
> +               return rc;
> +
>         /* Reset VCPU */
>         kvm_riscv_reset_vcpu(vcpu);
>
> @@ -220,6 +228,9 @@ void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
>
>  void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
>  {
> +       /* Cleanup VCPU AIA context */
> +       kvm_riscv_vcpu_aia_deinit(vcpu);
> +
>         /* Cleanup VCPU timer */
>         kvm_riscv_vcpu_timer_deinit(vcpu);
>
> @@ -741,6 +752,9 @@ void kvm_riscv_vcpu_flush_interrupts(struct kvm_vcpu *vcpu)
>                 csr->hvip &= ~mask;
>                 csr->hvip |= val;
>         }
> +
> +       /* Flush AIA high interrupts */
> +       kvm_riscv_vcpu_aia_flush_interrupts(vcpu);
>  }
>
>  void kvm_riscv_vcpu_sync_interrupts(struct kvm_vcpu *vcpu)
> @@ -766,6 +780,9 @@ void kvm_riscv_vcpu_sync_interrupts(struct kvm_vcpu *vcpu)
>                 }
>         }
>
> +       /* Sync-up AIA high interrupts */
> +       kvm_riscv_vcpu_aia_sync_interrupts(vcpu);
> +
>         /* Sync-up timer CSRs */
>         kvm_riscv_vcpu_timer_sync(vcpu);
>  }
> @@ -802,10 +819,15 @@ int kvm_riscv_vcpu_unset_interrupt(struct kvm_vcpu *vcpu, unsigned int irq)
>
>  bool kvm_riscv_vcpu_has_interrupts(struct kvm_vcpu *vcpu, unsigned long mask)
>  {
> -       unsigned long ie = ((vcpu->arch.guest_csr.vsie & VSIP_VALID_MASK)
> -                           << VSIP_TO_HVIP_SHIFT) & mask;
> +       unsigned long ie;
> +
> +       ie = ((vcpu->arch.guest_csr.vsie & VSIP_VALID_MASK)
> +               << VSIP_TO_HVIP_SHIFT) & mask;
> +       if (READ_ONCE(vcpu->arch.irqs_pending) & ie)
> +               return true;
>
> -       return (READ_ONCE(vcpu->arch.irqs_pending) & ie) ? true : false;
> +       /* Check AIA high interrupts */
> +       return kvm_riscv_vcpu_aia_has_interrupts(vcpu, mask);
>  }
>
>  void kvm_riscv_vcpu_power_off(struct kvm_vcpu *vcpu)
> @@ -901,6 +923,8 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
>         kvm_riscv_vcpu_guest_fp_restore(&vcpu->arch.guest_context,
>                                         vcpu->arch.isa);
>
> +       kvm_riscv_vcpu_aia_load(vcpu, cpu);
> +
>         vcpu->cpu = cpu;
>  }
>
> @@ -910,6 +934,8 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
>
>         vcpu->cpu = -1;
>
> +       kvm_riscv_vcpu_aia_put(vcpu);
> +
>         kvm_riscv_vcpu_guest_fp_save(&vcpu->arch.guest_context,
>                                      vcpu->arch.isa);
>         kvm_riscv_vcpu_host_fp_restore(&vcpu->arch.host_context);
> @@ -977,6 +1003,7 @@ static void kvm_riscv_update_hvip(struct kvm_vcpu *vcpu)
>         struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr;
>
>         csr_write(CSR_HVIP, csr->hvip);
> +       kvm_riscv_vcpu_aia_update_hvip(vcpu);
>  }
>
>  /*
> @@ -1051,6 +1078,13 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
>
>                 local_irq_disable();
>
> +               /* Update AIA HW state before entering guest */
> +               ret = kvm_riscv_vcpu_aia_update(vcpu);
> +               if (ret <= 0) {
> +                       local_irq_enable();
> +                       continue;
> +               }
> +

Can we update AIA hw state with only preemption disabled ?
For CoVE (aka AP-TEE), we need interrupts enabled to issue IPIs in
multiple scenarios.

>                 /*
>                  * Ensure we set mode to IN_GUEST_MODE after we disable
>                  * interrupts and before the final VCPU requests check.
> diff --git a/arch/riscv/kvm/vcpu_insn.c b/arch/riscv/kvm/vcpu_insn.c
> index f689337b78ff..7a6abed41bc1 100644
> --- a/arch/riscv/kvm/vcpu_insn.c
> +++ b/arch/riscv/kvm/vcpu_insn.c
> @@ -214,6 +214,7 @@ struct csr_func {
>  };
>
>  static const struct csr_func csr_funcs[] = {
> +       KVM_RISCV_VCPU_AIA_CSR_FUNCS
>         KVM_RISCV_VCPU_HPMCOUNTER_CSR_FUNCS
>  };
>
> diff --git a/arch/riscv/kvm/vm.c b/arch/riscv/kvm/vm.c
> index 65a964d7e70d..bc03d2ddcb51 100644
> --- a/arch/riscv/kvm/vm.c
> +++ b/arch/riscv/kvm/vm.c
> @@ -41,6 +41,8 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
>                 return r;
>         }
>
> +       kvm_riscv_aia_init_vm(kvm);
> +
>         kvm_riscv_guest_timer_init(kvm);
>
>         return 0;
> @@ -49,6 +51,8 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
>  void kvm_arch_destroy_vm(struct kvm *kvm)
>  {
>         kvm_destroy_vcpus(kvm);
> +
> +       kvm_riscv_aia_destroy_vm(kvm);
>  }
>
>  int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
> --
> 2.34.1
>
  
Anup Patel April 4, 2023, 3:22 a.m. UTC | #3
On Tue, Apr 4, 2023 at 5:20 AM Atish Patra <atishp@atishpatra.org> wrote:
>
> On Mon, Apr 3, 2023 at 3:03 PM Anup Patel <apatel@ventanamicro.com> wrote:
> >
> > To incrementally implement AIA support, we first add minimal skeletal
> > support which only compiles and detects AIA hardware support at the
> > boot-time but does not provide any functionality.
> >
> > Signed-off-by: Anup Patel <apatel@ventanamicro.com>
> > Reviewed-by: Atish Patra <atishp@rivosinc.com>
> > ---
> >  arch/riscv/include/asm/hwcap.h    |   6 ++
> >  arch/riscv/include/asm/kvm_aia.h  | 109 ++++++++++++++++++++++++++++++
> >  arch/riscv/include/asm/kvm_host.h |   7 ++
> >  arch/riscv/kvm/Makefile           |   1 +
> >  arch/riscv/kvm/aia.c              |  66 ++++++++++++++++++
> >  arch/riscv/kvm/main.c             |  22 +++++-
> >  arch/riscv/kvm/vcpu.c             |  40 ++++++++++-
> >  arch/riscv/kvm/vcpu_insn.c        |   1 +
> >  arch/riscv/kvm/vm.c               |   4 ++
> >  9 files changed, 252 insertions(+), 4 deletions(-)
> >  create mode 100644 arch/riscv/include/asm/kvm_aia.h
> >  create mode 100644 arch/riscv/kvm/aia.c
> >
> > diff --git a/arch/riscv/include/asm/hwcap.h b/arch/riscv/include/asm/hwcap.h
> > index 9c8ae4399565..8087e11a5cf8 100644
> > --- a/arch/riscv/include/asm/hwcap.h
> > +++ b/arch/riscv/include/asm/hwcap.h
> > @@ -48,6 +48,12 @@
> >  #define RISCV_ISA_EXT_MAX              64
> >  #define RISCV_ISA_EXT_NAME_LEN_MAX     32
> >
> > +#ifdef CONFIG_RISCV_M_MODE
> > +#define RISCV_ISA_EXT_SxAIA            RISCV_ISA_EXT_SMAIA
> > +#else
> > +#define RISCV_ISA_EXT_SxAIA            RISCV_ISA_EXT_SSAIA
> > +#endif
> > +
> >  #ifndef __ASSEMBLY__
> >
> >  #include <linux/jump_label.h>
> > diff --git a/arch/riscv/include/asm/kvm_aia.h b/arch/riscv/include/asm/kvm_aia.h
> > new file mode 100644
> > index 000000000000..258a835d4c32
> > --- /dev/null
> > +++ b/arch/riscv/include/asm/kvm_aia.h
> > @@ -0,0 +1,109 @@
> > +/* SPDX-License-Identifier: GPL-2.0-only */
> > +/*
> > + * Copyright (C) 2021 Western Digital Corporation or its affiliates.
> > + * Copyright (C) 2022 Ventana Micro Systems Inc.
> > + *
> > + * Authors:
> > + *     Anup Patel <apatel@ventanamicro.com>
> > + */
> > +
> > +#ifndef __KVM_RISCV_AIA_H
> > +#define __KVM_RISCV_AIA_H
> > +
> > +#include <linux/jump_label.h>
> > +#include <linux/kvm_types.h>
> > +
> > +struct kvm_aia {
> > +       /* In-kernel irqchip created */
> > +       bool            in_kernel;
> > +
> > +       /* In-kernel irqchip initialized */
> > +       bool            initialized;
> > +};
> > +
> > +struct kvm_vcpu_aia {
> > +};
> > +
> > +#define kvm_riscv_aia_initialized(k)   ((k)->arch.aia.initialized)
> > +
> > +#define irqchip_in_kernel(k)           ((k)->arch.aia.in_kernel)
> > +
> > +DECLARE_STATIC_KEY_FALSE(kvm_riscv_aia_available);
> > +#define kvm_riscv_aia_available() \
> > +       static_branch_unlikely(&kvm_riscv_aia_available)
> > +
> > +static inline void kvm_riscv_vcpu_aia_flush_interrupts(struct kvm_vcpu *vcpu)
> > +{
> > +}
> > +
> > +static inline void kvm_riscv_vcpu_aia_sync_interrupts(struct kvm_vcpu *vcpu)
> > +{
> > +}
> > +
> > +static inline bool kvm_riscv_vcpu_aia_has_interrupts(struct kvm_vcpu *vcpu,
> > +                                                    u64 mask)
> > +{
> > +       return false;
> > +}
> > +
> > +static inline void kvm_riscv_vcpu_aia_update_hvip(struct kvm_vcpu *vcpu)
> > +{
> > +}
> > +
> > +static inline void kvm_riscv_vcpu_aia_load(struct kvm_vcpu *vcpu, int cpu)
> > +{
> > +}
> > +
> > +static inline void kvm_riscv_vcpu_aia_put(struct kvm_vcpu *vcpu)
> > +{
> > +}
> > +
> > +static inline int kvm_riscv_vcpu_aia_get_csr(struct kvm_vcpu *vcpu,
> > +                                            unsigned long reg_num,
> > +                                            unsigned long *out_val)
> > +{
> > +       *out_val = 0;
> > +       return 0;
> > +}
> > +
> > +static inline int kvm_riscv_vcpu_aia_set_csr(struct kvm_vcpu *vcpu,
> > +                                            unsigned long reg_num,
> > +                                            unsigned long val)
> > +{
> > +       return 0;
> > +}
> > +
> > +#define KVM_RISCV_VCPU_AIA_CSR_FUNCS
> > +
> > +static inline int kvm_riscv_vcpu_aia_update(struct kvm_vcpu *vcpu)
> > +{
> > +       return 1;
> > +}
> > +
> > +static inline void kvm_riscv_vcpu_aia_reset(struct kvm_vcpu *vcpu)
> > +{
> > +}
> > +
> > +static inline int kvm_riscv_vcpu_aia_init(struct kvm_vcpu *vcpu)
> > +{
> > +       return 0;
> > +}
> > +
> > +static inline void kvm_riscv_vcpu_aia_deinit(struct kvm_vcpu *vcpu)
> > +{
> > +}
> > +
> > +static inline void kvm_riscv_aia_init_vm(struct kvm *kvm)
> > +{
> > +}
> > +
> > +static inline void kvm_riscv_aia_destroy_vm(struct kvm *kvm)
> > +{
> > +}
> > +
> > +void kvm_riscv_aia_enable(void);
> > +void kvm_riscv_aia_disable(void);
> > +int kvm_riscv_aia_init(void);
> > +void kvm_riscv_aia_exit(void);
> > +
> > +#endif
> > diff --git a/arch/riscv/include/asm/kvm_host.h b/arch/riscv/include/asm/kvm_host.h
> > index cc7da66ee0c0..3157cf748df1 100644
> > --- a/arch/riscv/include/asm/kvm_host.h
> > +++ b/arch/riscv/include/asm/kvm_host.h
> > @@ -14,6 +14,7 @@
> >  #include <linux/kvm_types.h>
> >  #include <linux/spinlock.h>
> >  #include <asm/hwcap.h>
> > +#include <asm/kvm_aia.h>
> >  #include <asm/kvm_vcpu_fp.h>
> >  #include <asm/kvm_vcpu_insn.h>
> >  #include <asm/kvm_vcpu_sbi.h>
> > @@ -94,6 +95,9 @@ struct kvm_arch {
> >
> >         /* Guest Timer */
> >         struct kvm_guest_timer timer;
> > +
> > +       /* AIA Guest/VM context */
> > +       struct kvm_aia aia;
> >  };
> >
> >  struct kvm_cpu_trap {
> > @@ -221,6 +225,9 @@ struct kvm_vcpu_arch {
> >         /* SBI context */
> >         struct kvm_vcpu_sbi_context sbi_context;
> >
> > +       /* AIA VCPU context */
> > +       struct kvm_vcpu_aia aia_context;
> > +
> >         /* Cache pages needed to program page tables with spinlock held */
> >         struct kvm_mmu_memory_cache mmu_page_cache;
> >
> > diff --git a/arch/riscv/kvm/Makefile b/arch/riscv/kvm/Makefile
> > index 278e97c06e0a..8031b8912a0d 100644
> > --- a/arch/riscv/kvm/Makefile
> > +++ b/arch/riscv/kvm/Makefile
> > @@ -26,3 +26,4 @@ kvm-y += vcpu_sbi_replace.o
> >  kvm-y += vcpu_sbi_hsm.o
> >  kvm-y += vcpu_timer.o
> >  kvm-$(CONFIG_RISCV_PMU_SBI) += vcpu_pmu.o vcpu_sbi_pmu.o
> > +kvm-y += aia.o
> > diff --git a/arch/riscv/kvm/aia.c b/arch/riscv/kvm/aia.c
> > new file mode 100644
> > index 000000000000..7a633331cd3e
> > --- /dev/null
> > +++ b/arch/riscv/kvm/aia.c
> > @@ -0,0 +1,66 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * Copyright (C) 2021 Western Digital Corporation or its affiliates.
> > + * Copyright (C) 2022 Ventana Micro Systems Inc.
> > + *
> > + * Authors:
> > + *     Anup Patel <apatel@ventanamicro.com>
> > + */
> > +
> > +#include <linux/kvm_host.h>
> > +#include <asm/hwcap.h>
> > +
> > +DEFINE_STATIC_KEY_FALSE(kvm_riscv_aia_available);
> > +
> > +static void aia_set_hvictl(bool ext_irq_pending)
> > +{
> > +       unsigned long hvictl;
> > +
> > +       /*
> > +        * HVICTL.IID == 9 and HVICTL.IPRIO == 0 represents
> > +        * no interrupt in HVICTL.
> > +        */
> > +
> > +       hvictl = (IRQ_S_EXT << HVICTL_IID_SHIFT) & HVICTL_IID;
> > +       hvictl |= ext_irq_pending;
> > +       csr_write(CSR_HVICTL, hvictl);
> > +}
> > +
> > +void kvm_riscv_aia_enable(void)
> > +{
> > +       if (!kvm_riscv_aia_available())
> > +               return;
> > +
> > +       aia_set_hvictl(false);
> > +       csr_write(CSR_HVIPRIO1, 0x0);
> > +       csr_write(CSR_HVIPRIO2, 0x0);
> > +#ifdef CONFIG_32BIT
> > +       csr_write(CSR_HVIPH, 0x0);
> > +       csr_write(CSR_HIDELEGH, 0x0);
> > +       csr_write(CSR_HVIPRIO1H, 0x0);
> > +       csr_write(CSR_HVIPRIO2H, 0x0);
> > +#endif
> > +}
> > +
> > +void kvm_riscv_aia_disable(void)
> > +{
> > +       if (!kvm_riscv_aia_available())
> > +               return;
> > +
> > +       aia_set_hvictl(false);
> > +}
> > +
> > +int kvm_riscv_aia_init(void)
> > +{
> > +       if (!riscv_isa_extension_available(NULL, SxAIA))
> > +               return -ENODEV;
> > +
> > +       /* Enable KVM AIA support */
> > +       static_branch_enable(&kvm_riscv_aia_available);
> > +
> > +       return 0;
> > +}
> > +
> > +void kvm_riscv_aia_exit(void)
> > +{
> > +}
> > diff --git a/arch/riscv/kvm/main.c b/arch/riscv/kvm/main.c
> > index 41ad7639a17b..6396352b4e4d 100644
> > --- a/arch/riscv/kvm/main.c
> > +++ b/arch/riscv/kvm/main.c
> > @@ -44,11 +44,15 @@ int kvm_arch_hardware_enable(void)
> >
> >         csr_write(CSR_HVIP, 0);
> >
> > +       kvm_riscv_aia_enable();
> > +
> >         return 0;
> >  }
> >
> >  void kvm_arch_hardware_disable(void)
> >  {
> > +       kvm_riscv_aia_disable();
> > +
> >         /*
> >          * After clearing the hideleg CSR, the host kernel will receive
> >          * spurious interrupts if hvip CSR has pending interrupts and the
> > @@ -63,6 +67,7 @@ void kvm_arch_hardware_disable(void)
> >
> >  static int __init riscv_kvm_init(void)
> >  {
> > +       int rc;
> >         const char *str;
> >
> >         if (!riscv_isa_extension_available(NULL, h)) {
> > @@ -84,6 +89,10 @@ static int __init riscv_kvm_init(void)
> >
> >         kvm_riscv_gstage_vmid_detect();
> >
> > +       rc = kvm_riscv_aia_init();
> > +       if (rc && rc != -ENODEV)
> > +               return rc;
> > +
> >         kvm_info("hypervisor extension available\n");
> >
> >         switch (kvm_riscv_gstage_mode()) {
> > @@ -106,12 +115,23 @@ static int __init riscv_kvm_init(void)
> >
> >         kvm_info("VMID %ld bits available\n", kvm_riscv_gstage_vmid_bits());
> >
> > -       return kvm_init(sizeof(struct kvm_vcpu), 0, THIS_MODULE);
> > +       if (kvm_riscv_aia_available())
> > +               kvm_info("AIA available\n");
> > +
> > +       rc = kvm_init(sizeof(struct kvm_vcpu), 0, THIS_MODULE);
> > +       if (rc) {
> > +               kvm_riscv_aia_exit();
> > +               return rc;
> > +       }
> > +
> > +       return 0;
> >  }
> >  module_init(riscv_kvm_init);
> >
> >  static void __exit riscv_kvm_exit(void)
> >  {
> > +       kvm_riscv_aia_exit();
> > +
> >         kvm_exit();
> >  }
> >  module_exit(riscv_kvm_exit);
> > diff --git a/arch/riscv/kvm/vcpu.c b/arch/riscv/kvm/vcpu.c
> > index 02b49cb94561..1fd54ec15622 100644
> > --- a/arch/riscv/kvm/vcpu.c
> > +++ b/arch/riscv/kvm/vcpu.c
> > @@ -137,6 +137,8 @@ static void kvm_riscv_reset_vcpu(struct kvm_vcpu *vcpu)
> >
> >         kvm_riscv_vcpu_timer_reset(vcpu);
> >
> > +       kvm_riscv_vcpu_aia_reset(vcpu);
> > +
> >         WRITE_ONCE(vcpu->arch.irqs_pending, 0);
> >         WRITE_ONCE(vcpu->arch.irqs_pending_mask, 0);
> >
> > @@ -159,6 +161,7 @@ int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
> >
> >  int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
> >  {
> > +       int rc;
> >         struct kvm_cpu_context *cntx;
> >         struct kvm_vcpu_csr *reset_csr = &vcpu->arch.guest_reset_csr;
> >         unsigned long host_isa, i;
> > @@ -201,6 +204,11 @@ int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
> >         /* setup performance monitoring */
> >         kvm_riscv_vcpu_pmu_init(vcpu);
> >
> > +       /* Setup VCPU AIA */
> > +       rc = kvm_riscv_vcpu_aia_init(vcpu);
> > +       if (rc)
> > +               return rc;
> > +
> >         /* Reset VCPU */
> >         kvm_riscv_reset_vcpu(vcpu);
> >
> > @@ -220,6 +228,9 @@ void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
> >
> >  void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
> >  {
> > +       /* Cleanup VCPU AIA context */
> > +       kvm_riscv_vcpu_aia_deinit(vcpu);
> > +
> >         /* Cleanup VCPU timer */
> >         kvm_riscv_vcpu_timer_deinit(vcpu);
> >
> > @@ -741,6 +752,9 @@ void kvm_riscv_vcpu_flush_interrupts(struct kvm_vcpu *vcpu)
> >                 csr->hvip &= ~mask;
> >                 csr->hvip |= val;
> >         }
> > +
> > +       /* Flush AIA high interrupts */
> > +       kvm_riscv_vcpu_aia_flush_interrupts(vcpu);
> >  }
> >
> >  void kvm_riscv_vcpu_sync_interrupts(struct kvm_vcpu *vcpu)
> > @@ -766,6 +780,9 @@ void kvm_riscv_vcpu_sync_interrupts(struct kvm_vcpu *vcpu)
> >                 }
> >         }
> >
> > +       /* Sync-up AIA high interrupts */
> > +       kvm_riscv_vcpu_aia_sync_interrupts(vcpu);
> > +
> >         /* Sync-up timer CSRs */
> >         kvm_riscv_vcpu_timer_sync(vcpu);
> >  }
> > @@ -802,10 +819,15 @@ int kvm_riscv_vcpu_unset_interrupt(struct kvm_vcpu *vcpu, unsigned int irq)
> >
> >  bool kvm_riscv_vcpu_has_interrupts(struct kvm_vcpu *vcpu, unsigned long mask)
> >  {
> > -       unsigned long ie = ((vcpu->arch.guest_csr.vsie & VSIP_VALID_MASK)
> > -                           << VSIP_TO_HVIP_SHIFT) & mask;
> > +       unsigned long ie;
> > +
> > +       ie = ((vcpu->arch.guest_csr.vsie & VSIP_VALID_MASK)
> > +               << VSIP_TO_HVIP_SHIFT) & mask;
> > +       if (READ_ONCE(vcpu->arch.irqs_pending) & ie)
> > +               return true;
> >
> > -       return (READ_ONCE(vcpu->arch.irqs_pending) & ie) ? true : false;
> > +       /* Check AIA high interrupts */
> > +       return kvm_riscv_vcpu_aia_has_interrupts(vcpu, mask);
> >  }
> >
> >  void kvm_riscv_vcpu_power_off(struct kvm_vcpu *vcpu)
> > @@ -901,6 +923,8 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
> >         kvm_riscv_vcpu_guest_fp_restore(&vcpu->arch.guest_context,
> >                                         vcpu->arch.isa);
> >
> > +       kvm_riscv_vcpu_aia_load(vcpu, cpu);
> > +
> >         vcpu->cpu = cpu;
> >  }
> >
> > @@ -910,6 +934,8 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
> >
> >         vcpu->cpu = -1;
> >
> > +       kvm_riscv_vcpu_aia_put(vcpu);
> > +
> >         kvm_riscv_vcpu_guest_fp_save(&vcpu->arch.guest_context,
> >                                      vcpu->arch.isa);
> >         kvm_riscv_vcpu_host_fp_restore(&vcpu->arch.host_context);
> > @@ -977,6 +1003,7 @@ static void kvm_riscv_update_hvip(struct kvm_vcpu *vcpu)
> >         struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr;
> >
> >         csr_write(CSR_HVIP, csr->hvip);
> > +       kvm_riscv_vcpu_aia_update_hvip(vcpu);
> >  }
> >
> >  /*
> > @@ -1051,6 +1078,13 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
> >
> >                 local_irq_disable();
> >
> > +               /* Update AIA HW state before entering guest */
> > +               ret = kvm_riscv_vcpu_aia_update(vcpu);
> > +               if (ret <= 0) {
> > +                       local_irq_enable();
> > +                       continue;
> > +               }
> > +
>
> Can we update AIA hw state with only preemption disabled ?
> For CoVE (aka AP-TEE), we need interrupts enabled to issue IPIs in
> multiple scenarios.

Okay, I will update in the next revision.

Regards,
Anup

>
> >                 /*
> >                  * Ensure we set mode to IN_GUEST_MODE after we disable
> >                  * interrupts and before the final VCPU requests check.
> > diff --git a/arch/riscv/kvm/vcpu_insn.c b/arch/riscv/kvm/vcpu_insn.c
> > index f689337b78ff..7a6abed41bc1 100644
> > --- a/arch/riscv/kvm/vcpu_insn.c
> > +++ b/arch/riscv/kvm/vcpu_insn.c
> > @@ -214,6 +214,7 @@ struct csr_func {
> >  };
> >
> >  static const struct csr_func csr_funcs[] = {
> > +       KVM_RISCV_VCPU_AIA_CSR_FUNCS
> >         KVM_RISCV_VCPU_HPMCOUNTER_CSR_FUNCS
> >  };
> >
> > diff --git a/arch/riscv/kvm/vm.c b/arch/riscv/kvm/vm.c
> > index 65a964d7e70d..bc03d2ddcb51 100644
> > --- a/arch/riscv/kvm/vm.c
> > +++ b/arch/riscv/kvm/vm.c
> > @@ -41,6 +41,8 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
> >                 return r;
> >         }
> >
> > +       kvm_riscv_aia_init_vm(kvm);
> > +
> >         kvm_riscv_guest_timer_init(kvm);
> >
> >         return 0;
> > @@ -49,6 +51,8 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
> >  void kvm_arch_destroy_vm(struct kvm *kvm)
> >  {
> >         kvm_destroy_vcpus(kvm);
> > +
> > +       kvm_riscv_aia_destroy_vm(kvm);
> >  }
> >
> >  int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
> > --
> > 2.34.1
> >
>
>
> --
> Regards,
> Atish
  

Patch

diff --git a/arch/riscv/include/asm/hwcap.h b/arch/riscv/include/asm/hwcap.h
index 9c8ae4399565..8087e11a5cf8 100644
--- a/arch/riscv/include/asm/hwcap.h
+++ b/arch/riscv/include/asm/hwcap.h
@@ -48,6 +48,12 @@ 
 #define RISCV_ISA_EXT_MAX		64
 #define RISCV_ISA_EXT_NAME_LEN_MAX	32
 
+#ifdef CONFIG_RISCV_M_MODE
+#define RISCV_ISA_EXT_SxAIA		RISCV_ISA_EXT_SMAIA
+#else
+#define RISCV_ISA_EXT_SxAIA		RISCV_ISA_EXT_SSAIA
+#endif
+
 #ifndef __ASSEMBLY__
 
 #include <linux/jump_label.h>
diff --git a/arch/riscv/include/asm/kvm_aia.h b/arch/riscv/include/asm/kvm_aia.h
new file mode 100644
index 000000000000..258a835d4c32
--- /dev/null
+++ b/arch/riscv/include/asm/kvm_aia.h
@@ -0,0 +1,109 @@ 
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2021 Western Digital Corporation or its affiliates.
+ * Copyright (C) 2022 Ventana Micro Systems Inc.
+ *
+ * Authors:
+ *	Anup Patel <apatel@ventanamicro.com>
+ */
+
+#ifndef __KVM_RISCV_AIA_H
+#define __KVM_RISCV_AIA_H
+
+#include <linux/jump_label.h>
+#include <linux/kvm_types.h>
+
+struct kvm_aia {
+	/* In-kernel irqchip created */
+	bool		in_kernel;
+
+	/* In-kernel irqchip initialized */
+	bool		initialized;
+};
+
+struct kvm_vcpu_aia {
+};
+
+#define kvm_riscv_aia_initialized(k)	((k)->arch.aia.initialized)
+
+#define irqchip_in_kernel(k)		((k)->arch.aia.in_kernel)
+
+DECLARE_STATIC_KEY_FALSE(kvm_riscv_aia_available);
+#define kvm_riscv_aia_available() \
+	static_branch_unlikely(&kvm_riscv_aia_available)
+
+static inline void kvm_riscv_vcpu_aia_flush_interrupts(struct kvm_vcpu *vcpu)
+{
+}
+
+static inline void kvm_riscv_vcpu_aia_sync_interrupts(struct kvm_vcpu *vcpu)
+{
+}
+
+static inline bool kvm_riscv_vcpu_aia_has_interrupts(struct kvm_vcpu *vcpu,
+						     u64 mask)
+{
+	return false;
+}
+
+static inline void kvm_riscv_vcpu_aia_update_hvip(struct kvm_vcpu *vcpu)
+{
+}
+
+static inline void kvm_riscv_vcpu_aia_load(struct kvm_vcpu *vcpu, int cpu)
+{
+}
+
+static inline void kvm_riscv_vcpu_aia_put(struct kvm_vcpu *vcpu)
+{
+}
+
+static inline int kvm_riscv_vcpu_aia_get_csr(struct kvm_vcpu *vcpu,
+					     unsigned long reg_num,
+					     unsigned long *out_val)
+{
+	*out_val = 0;
+	return 0;
+}
+
+static inline int kvm_riscv_vcpu_aia_set_csr(struct kvm_vcpu *vcpu,
+					     unsigned long reg_num,
+					     unsigned long val)
+{
+	return 0;
+}
+
+#define KVM_RISCV_VCPU_AIA_CSR_FUNCS
+
+static inline int kvm_riscv_vcpu_aia_update(struct kvm_vcpu *vcpu)
+{
+	return 1;
+}
+
+static inline void kvm_riscv_vcpu_aia_reset(struct kvm_vcpu *vcpu)
+{
+}
+
+static inline int kvm_riscv_vcpu_aia_init(struct kvm_vcpu *vcpu)
+{
+	return 0;
+}
+
+static inline void kvm_riscv_vcpu_aia_deinit(struct kvm_vcpu *vcpu)
+{
+}
+
+static inline void kvm_riscv_aia_init_vm(struct kvm *kvm)
+{
+}
+
+static inline void kvm_riscv_aia_destroy_vm(struct kvm *kvm)
+{
+}
+
+void kvm_riscv_aia_enable(void);
+void kvm_riscv_aia_disable(void);
+int kvm_riscv_aia_init(void);
+void kvm_riscv_aia_exit(void);
+
+#endif
diff --git a/arch/riscv/include/asm/kvm_host.h b/arch/riscv/include/asm/kvm_host.h
index cc7da66ee0c0..3157cf748df1 100644
--- a/arch/riscv/include/asm/kvm_host.h
+++ b/arch/riscv/include/asm/kvm_host.h
@@ -14,6 +14,7 @@ 
 #include <linux/kvm_types.h>
 #include <linux/spinlock.h>
 #include <asm/hwcap.h>
+#include <asm/kvm_aia.h>
 #include <asm/kvm_vcpu_fp.h>
 #include <asm/kvm_vcpu_insn.h>
 #include <asm/kvm_vcpu_sbi.h>
@@ -94,6 +95,9 @@  struct kvm_arch {
 
 	/* Guest Timer */
 	struct kvm_guest_timer timer;
+
+	/* AIA Guest/VM context */
+	struct kvm_aia aia;
 };
 
 struct kvm_cpu_trap {
@@ -221,6 +225,9 @@  struct kvm_vcpu_arch {
 	/* SBI context */
 	struct kvm_vcpu_sbi_context sbi_context;
 
+	/* AIA VCPU context */
+	struct kvm_vcpu_aia aia_context;
+
 	/* Cache pages needed to program page tables with spinlock held */
 	struct kvm_mmu_memory_cache mmu_page_cache;
 
diff --git a/arch/riscv/kvm/Makefile b/arch/riscv/kvm/Makefile
index 278e97c06e0a..8031b8912a0d 100644
--- a/arch/riscv/kvm/Makefile
+++ b/arch/riscv/kvm/Makefile
@@ -26,3 +26,4 @@  kvm-y += vcpu_sbi_replace.o
 kvm-y += vcpu_sbi_hsm.o
 kvm-y += vcpu_timer.o
 kvm-$(CONFIG_RISCV_PMU_SBI) += vcpu_pmu.o vcpu_sbi_pmu.o
+kvm-y += aia.o
diff --git a/arch/riscv/kvm/aia.c b/arch/riscv/kvm/aia.c
new file mode 100644
index 000000000000..7a633331cd3e
--- /dev/null
+++ b/arch/riscv/kvm/aia.c
@@ -0,0 +1,66 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2021 Western Digital Corporation or its affiliates.
+ * Copyright (C) 2022 Ventana Micro Systems Inc.
+ *
+ * Authors:
+ *	Anup Patel <apatel@ventanamicro.com>
+ */
+
+#include <linux/kvm_host.h>
+#include <asm/hwcap.h>
+
+DEFINE_STATIC_KEY_FALSE(kvm_riscv_aia_available);
+
+static void aia_set_hvictl(bool ext_irq_pending)
+{
+	unsigned long hvictl;
+
+	/*
+	 * HVICTL.IID == 9 and HVICTL.IPRIO == 0 represents
+	 * no interrupt in HVICTL.
+	 */
+
+	hvictl = (IRQ_S_EXT << HVICTL_IID_SHIFT) & HVICTL_IID;
+	hvictl |= ext_irq_pending;
+	csr_write(CSR_HVICTL, hvictl);
+}
+
+void kvm_riscv_aia_enable(void)
+{
+	if (!kvm_riscv_aia_available())
+		return;
+
+	aia_set_hvictl(false);
+	csr_write(CSR_HVIPRIO1, 0x0);
+	csr_write(CSR_HVIPRIO2, 0x0);
+#ifdef CONFIG_32BIT
+	csr_write(CSR_HVIPH, 0x0);
+	csr_write(CSR_HIDELEGH, 0x0);
+	csr_write(CSR_HVIPRIO1H, 0x0);
+	csr_write(CSR_HVIPRIO2H, 0x0);
+#endif
+}
+
+void kvm_riscv_aia_disable(void)
+{
+	if (!kvm_riscv_aia_available())
+		return;
+
+	aia_set_hvictl(false);
+}
+
+int kvm_riscv_aia_init(void)
+{
+	if (!riscv_isa_extension_available(NULL, SxAIA))
+		return -ENODEV;
+
+	/* Enable KVM AIA support */
+	static_branch_enable(&kvm_riscv_aia_available);
+
+	return 0;
+}
+
+void kvm_riscv_aia_exit(void)
+{
+}
diff --git a/arch/riscv/kvm/main.c b/arch/riscv/kvm/main.c
index 41ad7639a17b..6396352b4e4d 100644
--- a/arch/riscv/kvm/main.c
+++ b/arch/riscv/kvm/main.c
@@ -44,11 +44,15 @@  int kvm_arch_hardware_enable(void)
 
 	csr_write(CSR_HVIP, 0);
 
+	kvm_riscv_aia_enable();
+
 	return 0;
 }
 
 void kvm_arch_hardware_disable(void)
 {
+	kvm_riscv_aia_disable();
+
 	/*
 	 * After clearing the hideleg CSR, the host kernel will receive
 	 * spurious interrupts if hvip CSR has pending interrupts and the
@@ -63,6 +67,7 @@  void kvm_arch_hardware_disable(void)
 
 static int __init riscv_kvm_init(void)
 {
+	int rc;
 	const char *str;
 
 	if (!riscv_isa_extension_available(NULL, h)) {
@@ -84,6 +89,10 @@  static int __init riscv_kvm_init(void)
 
 	kvm_riscv_gstage_vmid_detect();
 
+	rc = kvm_riscv_aia_init();
+	if (rc && rc != -ENODEV)
+		return rc;
+
 	kvm_info("hypervisor extension available\n");
 
 	switch (kvm_riscv_gstage_mode()) {
@@ -106,12 +115,23 @@  static int __init riscv_kvm_init(void)
 
 	kvm_info("VMID %ld bits available\n", kvm_riscv_gstage_vmid_bits());
 
-	return kvm_init(sizeof(struct kvm_vcpu), 0, THIS_MODULE);
+	if (kvm_riscv_aia_available())
+		kvm_info("AIA available\n");
+
+	rc = kvm_init(sizeof(struct kvm_vcpu), 0, THIS_MODULE);
+	if (rc) {
+		kvm_riscv_aia_exit();
+		return rc;
+	}
+
+	return 0;
 }
 module_init(riscv_kvm_init);
 
 static void __exit riscv_kvm_exit(void)
 {
+	kvm_riscv_aia_exit();
+
 	kvm_exit();
 }
 module_exit(riscv_kvm_exit);
diff --git a/arch/riscv/kvm/vcpu.c b/arch/riscv/kvm/vcpu.c
index 02b49cb94561..1fd54ec15622 100644
--- a/arch/riscv/kvm/vcpu.c
+++ b/arch/riscv/kvm/vcpu.c
@@ -137,6 +137,8 @@  static void kvm_riscv_reset_vcpu(struct kvm_vcpu *vcpu)
 
 	kvm_riscv_vcpu_timer_reset(vcpu);
 
+	kvm_riscv_vcpu_aia_reset(vcpu);
+
 	WRITE_ONCE(vcpu->arch.irqs_pending, 0);
 	WRITE_ONCE(vcpu->arch.irqs_pending_mask, 0);
 
@@ -159,6 +161,7 @@  int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
 
 int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
 {
+	int rc;
 	struct kvm_cpu_context *cntx;
 	struct kvm_vcpu_csr *reset_csr = &vcpu->arch.guest_reset_csr;
 	unsigned long host_isa, i;
@@ -201,6 +204,11 @@  int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
 	/* setup performance monitoring */
 	kvm_riscv_vcpu_pmu_init(vcpu);
 
+	/* Setup VCPU AIA */
+	rc = kvm_riscv_vcpu_aia_init(vcpu);
+	if (rc)
+		return rc;
+
 	/* Reset VCPU */
 	kvm_riscv_reset_vcpu(vcpu);
 
@@ -220,6 +228,9 @@  void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
 
 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
 {
+	/* Cleanup VCPU AIA context */
+	kvm_riscv_vcpu_aia_deinit(vcpu);
+
 	/* Cleanup VCPU timer */
 	kvm_riscv_vcpu_timer_deinit(vcpu);
 
@@ -741,6 +752,9 @@  void kvm_riscv_vcpu_flush_interrupts(struct kvm_vcpu *vcpu)
 		csr->hvip &= ~mask;
 		csr->hvip |= val;
 	}
+
+	/* Flush AIA high interrupts */
+	kvm_riscv_vcpu_aia_flush_interrupts(vcpu);
 }
 
 void kvm_riscv_vcpu_sync_interrupts(struct kvm_vcpu *vcpu)
@@ -766,6 +780,9 @@  void kvm_riscv_vcpu_sync_interrupts(struct kvm_vcpu *vcpu)
 		}
 	}
 
+	/* Sync-up AIA high interrupts */
+	kvm_riscv_vcpu_aia_sync_interrupts(vcpu);
+
 	/* Sync-up timer CSRs */
 	kvm_riscv_vcpu_timer_sync(vcpu);
 }
@@ -802,10 +819,15 @@  int kvm_riscv_vcpu_unset_interrupt(struct kvm_vcpu *vcpu, unsigned int irq)
 
 bool kvm_riscv_vcpu_has_interrupts(struct kvm_vcpu *vcpu, unsigned long mask)
 {
-	unsigned long ie = ((vcpu->arch.guest_csr.vsie & VSIP_VALID_MASK)
-			    << VSIP_TO_HVIP_SHIFT) & mask;
+	unsigned long ie;
+
+	ie = ((vcpu->arch.guest_csr.vsie & VSIP_VALID_MASK)
+		<< VSIP_TO_HVIP_SHIFT) & mask;
+	if (READ_ONCE(vcpu->arch.irqs_pending) & ie)
+		return true;
 
-	return (READ_ONCE(vcpu->arch.irqs_pending) & ie) ? true : false;
+	/* Check AIA high interrupts */
+	return kvm_riscv_vcpu_aia_has_interrupts(vcpu, mask);
 }
 
 void kvm_riscv_vcpu_power_off(struct kvm_vcpu *vcpu)
@@ -901,6 +923,8 @@  void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
 	kvm_riscv_vcpu_guest_fp_restore(&vcpu->arch.guest_context,
 					vcpu->arch.isa);
 
+	kvm_riscv_vcpu_aia_load(vcpu, cpu);
+
 	vcpu->cpu = cpu;
 }
 
@@ -910,6 +934,8 @@  void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
 
 	vcpu->cpu = -1;
 
+	kvm_riscv_vcpu_aia_put(vcpu);
+
 	kvm_riscv_vcpu_guest_fp_save(&vcpu->arch.guest_context,
 				     vcpu->arch.isa);
 	kvm_riscv_vcpu_host_fp_restore(&vcpu->arch.host_context);
@@ -977,6 +1003,7 @@  static void kvm_riscv_update_hvip(struct kvm_vcpu *vcpu)
 	struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr;
 
 	csr_write(CSR_HVIP, csr->hvip);
+	kvm_riscv_vcpu_aia_update_hvip(vcpu);
 }
 
 /*
@@ -1051,6 +1078,13 @@  int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
 
 		local_irq_disable();
 
+		/* Update AIA HW state before entering guest */
+		ret = kvm_riscv_vcpu_aia_update(vcpu);
+		if (ret <= 0) {
+			local_irq_enable();
+			continue;
+		}
+
 		/*
 		 * Ensure we set mode to IN_GUEST_MODE after we disable
 		 * interrupts and before the final VCPU requests check.
diff --git a/arch/riscv/kvm/vcpu_insn.c b/arch/riscv/kvm/vcpu_insn.c
index f689337b78ff..7a6abed41bc1 100644
--- a/arch/riscv/kvm/vcpu_insn.c
+++ b/arch/riscv/kvm/vcpu_insn.c
@@ -214,6 +214,7 @@  struct csr_func {
 };
 
 static const struct csr_func csr_funcs[] = {
+	KVM_RISCV_VCPU_AIA_CSR_FUNCS
 	KVM_RISCV_VCPU_HPMCOUNTER_CSR_FUNCS
 };
 
diff --git a/arch/riscv/kvm/vm.c b/arch/riscv/kvm/vm.c
index 65a964d7e70d..bc03d2ddcb51 100644
--- a/arch/riscv/kvm/vm.c
+++ b/arch/riscv/kvm/vm.c
@@ -41,6 +41,8 @@  int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
 		return r;
 	}
 
+	kvm_riscv_aia_init_vm(kvm);
+
 	kvm_riscv_guest_timer_init(kvm);
 
 	return 0;
@@ -49,6 +51,8 @@  int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
 void kvm_arch_destroy_vm(struct kvm *kvm)
 {
 	kvm_destroy_vcpus(kvm);
+
+	kvm_riscv_aia_destroy_vm(kvm);
 }
 
 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)