To emulate the ID registers, we need a place to storage the values of
the ID regsiters. Maybe putting them in sysreg file is a good idea.
This commit has no functional changes but only code refactor. When
initializing a vCPU, get the values of the ID registers from
arm64_ftr_regs and storage them in sysreg file. And we just read
the value from sysreg file when getting/setting the value of the ID
regs.
Signed-off-by: zhanghailiang <zhang.zhanghailiang@xxxxxxxxxx>
Signed-off-by: Peng Liang <liangpeng10@xxxxxxxxxx>
---
arch/arm64/include/asm/kvm_coproc.h | 2 ++
arch/arm64/include/asm/kvm_host.h | 9 ++++++++
arch/arm64/kvm/arm.c | 2 ++
arch/arm64/kvm/sys_regs.c | 33 +++++++++++++++++++++++++----
4 files changed, 42 insertions(+), 4 deletions(-)
diff --git a/arch/arm64/include/asm/kvm_coproc.h b/arch/arm64/include/asm/kvm_coproc.h
index d6bb40122fdb..76e8c3cb0662 100644
--- a/arch/arm64/include/asm/kvm_coproc.h
+++ b/arch/arm64/include/asm/kvm_coproc.h
@@ -35,4 +35,6 @@ int kvm_arm_sys_reg_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *);
int kvm_arm_sys_reg_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *);
unsigned long kvm_arm_num_sys_reg_descs(struct kvm_vcpu *vcpu);
+void kvm_arm_sys_reg_init(struct kvm_vcpu *vcpu);
+
#endif /* __ARM64_KVM_COPROC_H__ */
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 0aecbab6a7fb..1b18c53f519a 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -40,6 +40,12 @@
#define KVM_VCPU_MAX_FEATURES 7
+/*
+ * (Op0, Op1, CRn, CRm, Op2) of ID registers is (3, 0, 0, crm, op2), where
+ * 1<=crm<8, 0<=op2<8. Hence, the max number of ID registers is 56.
+ */
+#define KVM_ARM_ID_REG_MAX_NUM 56
+
#define KVM_REQ_SLEEP \
KVM_ARCH_REQ_FLAGS(0, KVM_REQUEST_WAIT | KVM_REQUEST_NO_WAKEUP)
#define KVM_REQ_IRQ_PENDING KVM_ARCH_REQ(1)
@@ -192,6 +198,9 @@ enum vcpu_sysreg {
CNTP_CVAL_EL0,
CNTP_CTL_EL0,
+ ID_REG_BASE,
+ ID_REG_END = ID_REG_BASE + KVM_ARM_ID_REG_MAX_NUM - 1,
+
/* 32bit specific registers. Keep them at the end of the range */
DACR32_EL2, /* Domain Access Control Register */
IFSR32_EL2, /* Instruction Fault Status Register */
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index 8f8fca47abfc..5a153a109317 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -278,6 +278,8 @@ int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
if (err)
return err;
+ kvm_arm_sys_reg_init(vcpu);
+
return create_hyp_mappings(vcpu, vcpu + 1, PAGE_HYP);
}
diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index 41348a7781d9..68ed83657c07 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -1116,13 +1116,16 @@ static bool access_arch_timer(struct kvm_vcpu *vcpu,
return true;
}
+#define ID_REG_INDEX(id) \
+ (ID_REG_BASE + (((sys_reg_CRm(id) - 1) << 3) | sys_reg_Op2(id)))
+
/* Read a sanitised cpufeature ID register by sys_reg_desc */
-static u64 read_id_reg(const struct kvm_vcpu *vcpu,
+static u64 read_id_reg(struct kvm_vcpu *vcpu,
struct sys_reg_desc const *r, bool raz)
{
u32 id = sys_reg((u32)r->Op0, (u32)r->Op1,
(u32)r->CRn, (u32)r->CRm, (u32)r->Op2);
- u64 val = raz ? 0 : read_sanitised_ftr_reg(id);
+ u64 val = raz ? 0 : __vcpu_sys_reg(vcpu, ID_REG_INDEX(id));
if (id == SYS_ID_AA64PFR0_EL1) {
if (!vcpu_has_sve(vcpu))
@@ -1267,7 +1270,7 @@ static int set_id_aa64zfr0_el1(struct kvm_vcpu *vcpu,
* are stored, and for set_id_reg() we don't allow the effective value
* to be changed.
*/
-static int __get_id_reg(const struct kvm_vcpu *vcpu,
+static int __get_id_reg(struct kvm_vcpu *vcpu,
const struct sys_reg_desc *rd, void __user *uaddr,
bool raz)
{
@@ -1277,7 +1280,7 @@ static int __get_id_reg(const struct kvm_vcpu *vcpu,
return reg_to_user(uaddr, &val, id);
}
-static int __set_id_reg(const struct kvm_vcpu *vcpu,
+static int __set_id_reg(struct kvm_vcpu *vcpu,
const struct sys_reg_desc *rd, void __user *uaddr,
bool raz)
{
@@ -2870,3 +2873,25 @@ void kvm_sys_reg_table_init(void)
/* Clear all higher bits. */
cache_levels &= (1 << (i*3))-1;
}
+
+static int save_id_reg(u32 id, u64 val, void *argp)
+{
+ struct kvm_vcpu *vcpu = argp;
+
+ /*
+ * (Op0, Op1, CRn, CRm, Op2) of ID registers is (3, 0, 0, crm, op2),
+ * where 1<=crm<8, 0<=op2<8.
+ */
+ if (sys_reg_Op0(id) == 3 && sys_reg_Op1(id) == 0 &&
+ sys_reg_CRn(id) == 0 && sys_reg_CRm(id) > 0 &&
+ sys_reg_CRm(id) < 8) {
+ __vcpu_sys_reg(vcpu, ID_REG_INDEX(id)) = val;
+ }
+
+ return 0;
+}
+
+void kvm_arm_sys_reg_init(struct kvm_vcpu *vcpu)
+{
+ arm64_cpu_ftr_regs_traverse(save_id_reg, vcpu);
+}
--
2.26.2
