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authorGravatar Atish Patra <atishp@rivosinc.com> 2022-07-22 09:50:47 -0700
committerGravatar Palmer Dabbelt <palmer@rivosinc.com> 2022-08-12 07:43:57 -0700
commit8f5cb44b1bae8520c0705ce348b30ffb1fdda43a (patch)
tree4e80fff0b3baebf935b46b2aa13a2c62678754a6 /arch/riscv/kvm/vcpu.c
parentperf: riscv_pmu{,_sbi}: Miscallenous improvement & fixes (diff)
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RISC-V: KVM: Support sstc extension
Sstc extension allows the guest to program the vstimecmp CSR directly instead of making an SBI call to the hypervisor to program the next event. The timer interrupt is also directly injected to the guest by the hardware in this case. To maintain backward compatibility, the hypervisors also update the vstimecmp in an SBI set_time call if the hardware supports it. Thus, the older kernels in guest also take advantage of the sstc extension. Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Atish Patra <atishp@rivosinc.com> Acked-by: Anup Patel <anup@brainfault.org> Link: https://lore.kernel.org/all/CAAhSdy2mb6wyqy0NAn9BcTWKMYEc0Z4zU3s3j7oNqBz6eDQ9sg@mail.gmail.com/ Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Diffstat (limited to 'arch/riscv/kvm/vcpu.c')
-rw-r--r--arch/riscv/kvm/vcpu.c8
1 files changed, 7 insertions, 1 deletions
diff --git a/arch/riscv/kvm/vcpu.c b/arch/riscv/kvm/vcpu.c
index 5d271b597613..d0f08d5b4282 100644
--- a/arch/riscv/kvm/vcpu.c
+++ b/arch/riscv/kvm/vcpu.c
@@ -52,6 +52,7 @@ static const unsigned long kvm_isa_ext_arr[] = {
RISCV_ISA_EXT_i,
RISCV_ISA_EXT_m,
RISCV_ISA_EXT_SVPBMT,
+ RISCV_ISA_EXT_SSTC,
};
static unsigned long kvm_riscv_vcpu_base2isa_ext(unsigned long base_ext)
@@ -85,6 +86,7 @@ static bool kvm_riscv_vcpu_isa_disable_allowed(unsigned long ext)
case KVM_RISCV_ISA_EXT_C:
case KVM_RISCV_ISA_EXT_I:
case KVM_RISCV_ISA_EXT_M:
+ case KVM_RISCV_ISA_EXT_SSTC:
return false;
default:
break;
@@ -203,7 +205,7 @@ void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
{
- return kvm_riscv_vcpu_has_interrupts(vcpu, 1UL << IRQ_VS_TIMER);
+ return kvm_riscv_vcpu_timer_pending(vcpu);
}
void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu)
@@ -785,6 +787,8 @@ static void kvm_riscv_vcpu_update_config(const unsigned long *isa)
if (__riscv_isa_extension_available(isa, RISCV_ISA_EXT_SVPBMT))
henvcfg |= ENVCFG_PBMTE;
+ if (__riscv_isa_extension_available(isa, RISCV_ISA_EXT_SSTC))
+ henvcfg |= ENVCFG_STCE;
csr_write(CSR_HENVCFG, henvcfg);
#ifdef CONFIG_32BIT
csr_write(CSR_HENVCFGH, henvcfg >> 32);
@@ -828,6 +832,8 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
vcpu->arch.isa);
kvm_riscv_vcpu_host_fp_restore(&vcpu->arch.host_context);
+ kvm_riscv_vcpu_timer_save(vcpu);
+
csr->vsstatus = csr_read(CSR_VSSTATUS);
csr->vsie = csr_read(CSR_VSIE);
csr->vstvec = csr_read(CSR_VSTVEC);