2023-04-03 09:38:09

by Anup Patel

[permalink] [raw]
Subject: [PATCH v3 4/8] RISC-V: KVM: Initial skeletal support for AIA

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 <[email protected]>
Reviewed-by: Atish Patra <[email protected]>
---
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 <[email protected]>
+ */
+
+#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 <[email protected]>
+ */
+
+#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)
--
2.34.1


2023-04-03 12:04:36

by Andrew Jones

[permalink] [raw]
Subject: Re: [PATCH v3 4/8] RISC-V: KVM: Initial skeletal support for AIA

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 <[email protected]>
> Reviewed-by: Atish Patra <[email protected]>
> ---
> 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 <[email protected]>

Thanks,
drew

2023-04-04 00:07:00

by Atish Patra

[permalink] [raw]
Subject: Re: [PATCH v3 4/8] RISC-V: KVM: Initial skeletal support for AIA

On Mon, Apr 3, 2023 at 3:03 PM Anup Patel <[email protected]> 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 <[email protected]>
> Reviewed-by: Atish Patra <[email protected]>
> ---
> 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 <[email protected]>
> + */
> +
> +#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 <[email protected]>
> + */
> +
> +#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
>


--
Regards,
Atish

2023-04-04 03:35:45

by Anup Patel

[permalink] [raw]
Subject: Re: [PATCH v3 4/8] RISC-V: KVM: Initial skeletal support for AIA

On Tue, Apr 4, 2023 at 5:20 AM Atish Patra <[email protected]> wrote:
>
> On Mon, Apr 3, 2023 at 3:03 PM Anup Patel <[email protected]> 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 <[email protected]>
> > Reviewed-by: Atish Patra <[email protected]>
> > ---
> > 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 <[email protected]>
> > + */
> > +
> > +#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 <[email protected]>
> > + */
> > +
> > +#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