@@ -94,6 +94,7 @@ enum emulation_result {
#define KVM_LARCH_FPU (0x1 << 0)
#define KVM_LARCH_SWCSR_LATEST (0x1 << 1)
#define KVM_LARCH_HWCSR_USABLE (0x1 << 2)
+#define KVM_LARCH_LSX (0x1 << 3)
struct kvm_vcpu_arch {
/*
@@ -175,6 +176,16 @@ static inline void writel_sw_gcsr(struct loongarch_csrs *csr, int reg, unsigned
csr->csrs[reg] = val;
}
+static inline bool kvm_guest_has_lsx(struct kvm_vcpu_arch *arch)
+{
+ return arch->cpucfg[2] & CPUCFG2_LSX;
+}
+
+static inline bool kvm_guest_has_fpu(struct kvm_vcpu_arch *arch)
+{
+ return arch->cpucfg[2] & CPUCFG2_FP;
+}
+
/* Debug: dump vcpu state */
int kvm_arch_vcpu_dump_regs(struct kvm_vcpu *vcpu);
@@ -55,6 +55,18 @@ void kvm_save_fpu(struct loongarch_fpu *fpu);
void kvm_restore_fpu(struct loongarch_fpu *fpu);
void kvm_restore_fcsr(struct loongarch_fpu *fpu);
+#ifdef CONFIG_CPU_HAS_LSX
+int kvm_own_lsx(struct kvm_vcpu *vcpu);
+void kvm_save_lsx(struct loongarch_fpu *fpu);
+void kvm_restore_lsx(struct loongarch_fpu *fpu);
+void kvm_restore_lsx_upper(struct loongarch_fpu *fpu);
+#else
+static inline int kvm_own_lsx(struct kvm_vcpu *vcpu) { }
+static inline void kvm_save_lsx(struct loongarch_fpu *fpu) { }
+static inline void kvm_restore_lsx(struct loongarch_fpu *fpu) { }
+static inline void kvm_restore_lsx_upper(struct loongarch_fpu *fpu) { }
+#endif
+
void kvm_acquire_timer(struct kvm_vcpu *vcpu);
void kvm_init_timer(struct kvm_vcpu *vcpu, unsigned long hz);
void kvm_reset_timer(struct kvm_vcpu *vcpu);
@@ -79,6 +79,7 @@ struct kvm_fpu {
#define LOONGARCH_REG_64(TYPE, REG) (TYPE | KVM_REG_SIZE_U64 | (REG << LOONGARCH_REG_SHIFT))
#define KVM_IOC_CSRID(REG) LOONGARCH_REG_64(KVM_REG_LOONGARCH_CSR, REG)
#define KVM_IOC_CPUCFG(REG) LOONGARCH_REG_64(KVM_REG_LOONGARCH_CPUCFG, REG)
+#define KVM_LOONGARCH_VCPU_CPUCFG 0
struct kvm_debug_exit_arch {
};
@@ -643,6 +643,11 @@ static int kvm_handle_fpu_disabled(struct kvm_vcpu *vcpu)
{
struct kvm_run *run = vcpu->run;
+ if (!kvm_guest_has_fpu(&vcpu->arch)) {
+ kvm_queue_exception(vcpu, EXCCODE_INE, 0);
+ return RESUME_GUEST;
+ }
+
/*
* If guest FPU not present, the FPU operation should have been
* treated as a reserved instruction!
@@ -659,6 +664,21 @@ static int kvm_handle_fpu_disabled(struct kvm_vcpu *vcpu)
return RESUME_GUEST;
}
+/*
+ * kvm_handle_lsx_disabled() - Guest used LSX while disabled in root.
+ * @vcpu: Virtual CPU context.
+ *
+ * Handle when the guest attempts to use LSX when it is disabled in the root
+ * context.
+ */
+static int kvm_handle_lsx_disabled(struct kvm_vcpu *vcpu)
+{
+ if (kvm_own_lsx(vcpu))
+ kvm_queue_exception(vcpu, EXCCODE_INE, 0);
+
+ return RESUME_GUEST;
+}
+
/*
* LoongArch KVM callback handling for unimplemented guest exiting
*/
@@ -687,6 +707,7 @@ static exit_handle_fn kvm_fault_tables[EXCCODE_INT_START] = {
[EXCCODE_TLBS] = kvm_handle_write_fault,
[EXCCODE_TLBM] = kvm_handle_write_fault,
[EXCCODE_FPDIS] = kvm_handle_fpu_disabled,
+ [EXCCODE_LSXDIS] = kvm_handle_lsx_disabled,
[EXCCODE_GSPR] = kvm_handle_gspr,
};
@@ -245,6 +245,27 @@ SYM_FUNC_START(kvm_restore_fpu)
jr ra
SYM_FUNC_END(kvm_restore_fpu)
+#ifdef CONFIG_CPU_HAS_LSX
+SYM_FUNC_START(kvm_save_lsx)
+ fpu_save_csr a0 t1
+ fpu_save_cc a0 t1 t2
+ lsx_save_data a0 t1
+ jr ra
+SYM_FUNC_END(kvm_save_lsx)
+
+SYM_FUNC_START(kvm_restore_lsx)
+ lsx_restore_data a0 t1
+ fpu_restore_cc a0 t1 t2
+ fpu_restore_csr a0 t1 t2
+ jr ra
+SYM_FUNC_END(kvm_restore_lsx)
+
+SYM_FUNC_START(kvm_restore_lsx_upper)
+ lsx_restore_all_upper a0 t0 t1
+ jr ra
+SYM_FUNC_END(kvm_restore_lsx_upper)
+#endif
+
.section ".rodata"
SYM_DATA(kvm_exception_size, .quad kvm_exc_entry_end - kvm_exc_entry)
SYM_DATA(kvm_enter_guest_size, .quad kvm_enter_guest_end - kvm_enter_guest)
@@ -102,6 +102,7 @@ TRACE_EVENT(kvm_exit_gspr,
#define KVM_TRACE_AUX_DISCARD 4
#define KVM_TRACE_AUX_FPU 1
+#define KVM_TRACE_AUX_LSX 2
#define kvm_trace_symbol_aux_op \
{ KVM_TRACE_AUX_SAVE, "save" }, \
@@ -111,7 +112,8 @@ TRACE_EVENT(kvm_exit_gspr,
{ KVM_TRACE_AUX_DISCARD, "discard" }
#define kvm_trace_symbol_aux_state \
- { KVM_TRACE_AUX_FPU, "FPU" }
+ { KVM_TRACE_AUX_FPU, "FPU" }, \
+ { KVM_TRACE_AUX_LSX, "LSX" }
TRACE_EVENT(kvm_aux,
TP_PROTO(struct kvm_vcpu *vcpu, unsigned int op,
@@ -309,6 +309,33 @@ static int _kvm_setcsr(struct kvm_vcpu *vcpu, unsigned int id, u64 val)
return ret;
}
+static int _kvm_loongarch_get_cpucfg_attr(int id, u64 *v)
+{
+ int ret = 0;
+
+ if (id < 0 && id >= KVM_MAX_CPUCFG_REGS)
+ return -EINVAL;
+
+ switch (id) {
+ case 2:
+ /* return CPUCFG2 features which have been supported by KVM */
+ *v = CPUCFG2_FP | CPUCFG2_FPSP | CPUCFG2_FPDP |
+ CPUCFG2_FPVERS | CPUCFG2_LLFTP | CPUCFG2_LLFTPREV |
+ CPUCFG2_LAM;
+ /*
+ * if LSX is supported by CPU, it is also supported by KVM,
+ * as we implement it.
+ */
+ if (cpu_has_lsx)
+ *v |= CPUCFG2_LSX;
+ break;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+ return ret;
+}
+
static int kvm_get_one_reg(struct kvm_vcpu *vcpu,
const struct kvm_one_reg *reg, u64 *v)
{
@@ -365,6 +392,42 @@ static int kvm_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
return ret;
}
+static int kvm_check_cpucfg(int id, u64 val)
+{
+ u64 mask;
+ int ret = 0;
+
+ if (id < 0 && id >= KVM_MAX_CPUCFG_REGS)
+ return -EINVAL;
+
+ if (_kvm_loongarch_get_cpucfg_attr(id, &mask))
+ return ret;
+
+ switch (id) {
+ case 2:
+ /* CPUCFG2 features checking */
+ if (val & ~mask)
+ /* The unsupported features should not be set */
+ ret = -EINVAL;
+ else if (!(val & CPUCFG2_LLFTP))
+ /* The LLFTP must be set, as guest must has a constant timer */
+ ret = -EINVAL;
+ else if ((val & CPUCFG2_FP) && (!(val & CPUCFG2_FPDP) || !(val & CPUCFG2_FPSP)))
+ /* Single and double float point must both be set when enable FP */
+ ret = -EINVAL;
+ else if ((val & CPUCFG2_LSX) && !(val & CPUCFG2_FP))
+ /* FP should be set when enable LSX */
+ ret = -EINVAL;
+ else if ((val & CPUCFG2_LASX) && !(val & CPUCFG2_LSX))
+ /* LSX,FP should be set when enable LASX, and FP has been checked before. */
+ ret = -EINVAL;
+ break;
+ default:
+ break;
+ }
+ return ret;
+}
+
static int kvm_set_one_reg(struct kvm_vcpu *vcpu,
const struct kvm_one_reg *reg, u64 v)
{
@@ -378,10 +441,10 @@ static int kvm_set_one_reg(struct kvm_vcpu *vcpu,
break;
case KVM_REG_LOONGARCH_CPUCFG:
id = KVM_GET_IOC_CPUCFG_IDX(reg->id);
- if (id >= 0 && id < KVM_MAX_CPUCFG_REGS)
- vcpu->arch.cpucfg[id] = (u32)v;
- else
- ret = -EINVAL;
+ ret = kvm_check_cpucfg(id, v);
+ if (ret)
+ break;
+ vcpu->arch.cpucfg[id] = (u32)v;
break;
case KVM_REG_LOONGARCH_KVM:
switch (reg->id) {
@@ -471,10 +534,95 @@ static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu,
return -EINVAL;
}
+static int kvm_loongarch_cpucfg_has_attr(struct kvm_vcpu *vcpu,
+ struct kvm_device_attr *attr)
+{
+ int ret = -ENXIO;
+
+ switch (attr->attr) {
+ case 2:
+ ret = 0;
+ break;
+ default:
+ break;
+ }
+
+ return ret;
+}
+
+static int kvm_loongarch_vcpu_has_attr(struct kvm_vcpu *vcpu,
+ struct kvm_device_attr *attr)
+{
+ int ret = -ENXIO;
+
+ switch (attr->group) {
+ case KVM_LOONGARCH_VCPU_CPUCFG:
+ ret = kvm_loongarch_cpucfg_has_attr(vcpu, attr);
+ break;
+ default:
+ break;
+ }
+
+ return ret;
+}
+
+static int kvm_loongarch_cpucfg_set_attr(struct kvm_vcpu *vcpu,
+ struct kvm_device_attr *attr)
+{
+ return -ENXIO;
+}
+
+static int kvm_loongarch_vcpu_set_attr(struct kvm_vcpu *vcpu,
+ struct kvm_device_attr *attr)
+{
+ int ret = -ENXIO;
+
+ switch (attr->group) {
+ case KVM_LOONGARCH_VCPU_CPUCFG:
+ ret = kvm_loongarch_cpucfg_set_attr(vcpu, attr);
+ break;
+ default:
+ break;
+ }
+
+ return ret;
+}
+
+static int kvm_loongarch_get_cpucfg_attr(struct kvm_vcpu *vcpu,
+ struct kvm_device_attr *attr)
+{
+ int ret = 0;
+ uint64_t val;
+ uint64_t __user *uaddr = (uint64_t __user *)(unsigned long long)attr->addr;
+
+ ret = _kvm_loongarch_get_cpucfg_attr(attr->attr, &val);
+ if (ret)
+ return ret;
+ put_user(val, uaddr);
+ return ret;
+}
+
+static int kvm_loongarch_vcpu_get_attr(struct kvm_vcpu *vcpu,
+ struct kvm_device_attr *attr)
+{
+ int ret = -ENXIO;
+
+ switch (attr->group) {
+ case KVM_LOONGARCH_VCPU_CPUCFG:
+ ret = kvm_loongarch_get_cpucfg_attr(vcpu, attr);
+ break;
+ default:
+ break;
+ }
+
+ return ret;
+}
+
long kvm_arch_vcpu_ioctl(struct file *filp,
unsigned int ioctl, unsigned long arg)
{
long r;
+ struct kvm_device_attr attr;
void __user *argp = (void __user *)arg;
struct kvm_vcpu *vcpu = filp->private_data;
@@ -514,6 +662,27 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
r = kvm_vcpu_ioctl_enable_cap(vcpu, &cap);
break;
}
+ case KVM_SET_DEVICE_ATTR: {
+ r = -EFAULT;
+ if (copy_from_user(&attr, argp, sizeof(attr)))
+ break;
+ r = kvm_loongarch_vcpu_set_attr(vcpu, &attr);
+ break;
+ }
+ case KVM_GET_DEVICE_ATTR: {
+ r = -EFAULT;
+ if (copy_from_user(&attr, argp, sizeof(attr)))
+ break;
+ r = kvm_loongarch_vcpu_get_attr(vcpu, &attr);
+ break;
+ }
+ case KVM_HAS_DEVICE_ATTR: {
+ r = -EFAULT;
+ if (copy_from_user(&attr, argp, sizeof(attr)))
+ break;
+ r = kvm_loongarch_vcpu_has_attr(vcpu, &attr);
+ break;
+ }
default:
r = -ENOIOCTLCMD;
break;
@@ -561,12 +730,54 @@ void kvm_own_fpu(struct kvm_vcpu *vcpu)
preempt_enable();
}
+#ifdef CONFIG_CPU_HAS_LSX
+/* Enable LSX for guest and restore context */
+int kvm_own_lsx(struct kvm_vcpu *vcpu)
+{
+ if (!kvm_guest_has_fpu(&vcpu->arch) || !kvm_guest_has_lsx(&vcpu->arch))
+ return -EINVAL;
+
+ preempt_disable();
+
+ /* Enable LSX for guest */
+ set_csr_euen(CSR_EUEN_LSXEN | CSR_EUEN_FPEN);
+ switch (vcpu->arch.aux_inuse & KVM_LARCH_FPU) {
+ case KVM_LARCH_FPU:
+ /*
+ * Guest FPU state already loaded,
+ * only restore upper LSX state
+ */
+ kvm_restore_lsx_upper(&vcpu->arch.fpu);
+ break;
+ default:
+ /* Neither FP or LSX already active,
+ * restore full LSX state
+ */
+ kvm_restore_lsx(&vcpu->arch.fpu);
+ break;
+ }
+
+ trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE, KVM_TRACE_AUX_LSX);
+ vcpu->arch.aux_inuse |= KVM_LARCH_LSX | KVM_LARCH_FPU;
+ preempt_enable();
+
+ return 0;
+}
+#endif
+
/* Save context and disable FPU */
void kvm_lose_fpu(struct kvm_vcpu *vcpu)
{
preempt_disable();
- if (vcpu->arch.aux_inuse & KVM_LARCH_FPU) {
+ if (vcpu->arch.aux_inuse & KVM_LARCH_LSX) {
+ kvm_save_lsx(&vcpu->arch.fpu);
+ vcpu->arch.aux_inuse &= ~(KVM_LARCH_LSX | KVM_LARCH_FPU);
+ trace_kvm_aux(vcpu, KVM_TRACE_AUX_SAVE, KVM_TRACE_AUX_LSX);
+
+ /* Disable LSX & FPU */
+ clear_csr_euen(CSR_EUEN_FPEN | CSR_EUEN_LSXEN);
+ } else if (vcpu->arch.aux_inuse & KVM_LARCH_FPU) {
kvm_save_fpu(&vcpu->arch.fpu);
vcpu->arch.aux_inuse &= ~KVM_LARCH_FPU;
trace_kvm_aux(vcpu, KVM_TRACE_AUX_SAVE, KVM_TRACE_AUX_FPU);