On 27/04/2024 01:44, Deepak Gupta wrote:
> On Thu, Apr 18, 2024 at 04:26:40PM +0200, Clément Léger wrote:
>> Add support for FWFT extension in KVM
>>
>> Signed-off-by: Clément Léger <cleger@xxxxxxxxxxxx>
>> ---
>> arch/riscv/include/asm/kvm_host.h | 5 +
>> arch/riscv/include/asm/kvm_vcpu_sbi.h | 1 +
>> arch/riscv/include/asm/kvm_vcpu_sbi_fwft.h | 37 ++++++
>> arch/riscv/include/uapi/asm/kvm.h | 1 +
>> arch/riscv/kvm/Makefile | 1 +
>> arch/riscv/kvm/vcpu.c | 5 +
>> arch/riscv/kvm/vcpu_sbi.c | 4 +
>> arch/riscv/kvm/vcpu_sbi_fwft.c | 136 +++++++++++++++++++++
>> 8 files changed, 190 insertions(+)
>> create mode 100644 arch/riscv/include/asm/kvm_vcpu_sbi_fwft.h
>> create mode 100644 arch/riscv/kvm/vcpu_sbi_fwft.c
>>
>> diff --git a/arch/riscv/include/asm/kvm_host.h
>> b/arch/riscv/include/asm/kvm_host.h
>> index 484d04a92fa6..be60aaa07f57 100644
>> --- a/arch/riscv/include/asm/kvm_host.h
>> +++ b/arch/riscv/include/asm/kvm_host.h
>> @@ -19,6 +19,7 @@
>> #include <asm/kvm_vcpu_fp.h>
>> #include <asm/kvm_vcpu_insn.h>
>> #include <asm/kvm_vcpu_sbi.h>
>> +#include <asm/kvm_vcpu_sbi_fwft.h>
>> #include <asm/kvm_vcpu_timer.h>
>> #include <asm/kvm_vcpu_pmu.h>
>>
>> @@ -169,6 +170,7 @@ struct kvm_vcpu_csr {
>> struct kvm_vcpu_config {
>> u64 henvcfg;
>> u64 hstateen0;
>> + u64 hedeleg;
>> };
>>
>> struct kvm_vcpu_smstateen_csr {
>> @@ -261,6 +263,9 @@ struct kvm_vcpu_arch {
>> /* Performance monitoring context */
>> struct kvm_pmu pmu_context;
>>
>> + /* Firmware feature SBI extension context */
>> + struct kvm_sbi_fwft fwft_context;
>> +
>> /* 'static' configurations which are set only once */
>> struct kvm_vcpu_config cfg;
>>
>> diff --git a/arch/riscv/include/asm/kvm_vcpu_sbi.h
>> b/arch/riscv/include/asm/kvm_vcpu_sbi.h
>> index b96705258cf9..3a33bbacc233 100644
>> --- a/arch/riscv/include/asm/kvm_vcpu_sbi.h
>> +++ b/arch/riscv/include/asm/kvm_vcpu_sbi.h
>> @@ -86,6 +86,7 @@ extern const struct kvm_vcpu_sbi_extension
>> vcpu_sbi_ext_srst;
>> extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_hsm;
>> extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_dbcn;
>> extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_sta;
>> +extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_fwft;
>> extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_experimental;
>> extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_vendor;
>>
>> diff --git a/arch/riscv/include/asm/kvm_vcpu_sbi_fwft.h
>> b/arch/riscv/include/asm/kvm_vcpu_sbi_fwft.h
>> new file mode 100644
>> index 000000000000..7dc1b80c7e6c
>> --- /dev/null
>> +++ b/arch/riscv/include/asm/kvm_vcpu_sbi_fwft.h
>> @@ -0,0 +1,37 @@
>> +/* SPDX-License-Identifier: GPL-2.0-only */
>> +/*
>> + * Copyright (c) 2023 Rivos Inc
>> + *
>> + * Authors:
>> + * Atish Patra <atishp@xxxxxxxxxxxx>
>
> nit: probably need to fix Copyright year and Authors here :-)
> Same in all new files being introduced.
>
>> + */
>> +
>> +#ifndef __KVM_VCPU_RISCV_FWFT_H
>> +#define __KVM_VCPU_RISCV_FWFT_H
>> +
>> +#include <asm/sbi.h>
>> +
>> +#define KVM_SBI_FWFT_FEATURE_COUNT 1
>> +
>> +static int kvm_sbi_fwft_set(struct kvm_vcpu *vcpu,
>> + enum sbi_fwft_feature_t feature,
>> + unsigned long value, unsigned long flags)
>> +{
>> + struct kvm_sbi_fwft_config *conf = kvm_sbi_fwft_get_config(vcpu,
>> + feature);
>> + if (!conf)
>> + return SBI_ERR_DENIED;
>
> Curious,
> Why denied and not something like NOT_SUPPORTED NOT_AVAILABLE here?
Hey Deepak,
So indeed, the return value is not totally correct since the spec states
that we return EDENIED if feature is reserved or is platform-specific
and unimplemented. But in that case it dos not distinguish between
defined features and reserved one. I'll add a check for that.
Thanks,
Clément
>
>> +
>> + if ((flags & ~SBI_FWFT_SET_FLAG_LOCK) != 0)
>> + return SBI_ERR_INVALID_PARAM;
>> +
>> + if (conf->flags & SBI_FWFT_SET_FLAG_LOCK)
>> + return SBI_ERR_DENIED;
>> +
>> + conf->flags = flags;
>> +
>> + return conf->feature->set(vcpu, conf, value);
>> +}
>> +
