[PATCH 3/3] KVM: riscv: selftests: Add vector extension tests

25 Mar 2025

Add vector related tests with the ISA extension standard template.
However, the vector registers are bit tricky as the register length is
variable based on vlenb value of the system. That's why the macros are
defined with a default and overidden with actual value at runtime.
Signed-off-by: Atish Patra atishp@rivosinc.com
---
 tools/testing/selftests/kvm/riscv/get-reg-list.c | 111 ++++++++++++++++++++++-
 1 file changed, 110 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/kvm/riscv/get-reg-list.c b/tools/testing/selftests/kvm/riscv/get-reg-list.c
index 8515921dfdbf..576ab8eb7368 100644
--- a/tools/testing/selftests/kvm/riscv/get-reg-list.c
+++ b/tools/testing/selftests/kvm/riscv/get-reg-list.c
@@ -145,7 +145,9 @@ void finalize_vcpu(struct kvm_vcpu *vcpu, struct vcpu_reg_list *c)
 {
    unsigned long isa_ext_state[KVM_RISCV_ISA_EXT_MAX] = { 0 };
    struct vcpu_reg_sublist *s;
-	uint64_t feature;
+	uint64_t feature = 0;
+	u64 reg, size;
+	unsigned long vlenb_reg;
    int rc;
for (int i = 0; i < KVM_RISCV_ISA_EXT_MAX; i++)
@@ -173,6 +175,23 @@ void finalize_vcpu(struct kvm_vcpu *vcpu, struct vcpu_reg_list *c)
    	switch (s->feature_type) {
    	case VCPU_FEATURE_ISA_EXT:
    		feature = RISCV_ISA_EXT_REG(s->feature);
+			if (s->feature == KVM_RISCV_ISA_EXT_V) {
+				/* Enable V extension so that we can get the vlenb register */
+				__vcpu_set_reg(vcpu, feature, 1);
+				/* Compute the correct vector register size */
+				rc = __vcpu_get_reg(vcpu, s->regs[4], &vlenb_reg);
+				if (rc < 0)
+				/* The vector test may fail if the default reg size doesn't match */
+					break;
+				size = __builtin_ctzl(vlenb_reg);
+				size <<= KVM_REG_SIZE_SHIFT;
+				for (int i = 0; i < 32; i++) {
+					reg = KVM_REG_RISCV | KVM_REG_RISCV_VECTOR | size |
+					      KVM_REG_RISCV_VECTOR_REG(i);
+					s->regs[5 + i] = reg;
+				}
+				__vcpu_set_reg(vcpu, feature, 0);
+			}
    		break;
    	case VCPU_FEATURE_SBI_EXT:
    		feature = RISCV_SBI_EXT_REG(s->feature);
@@ -408,6 +427,35 @@ static const char *fp_d_id_to_str(const char *prefix, __u64 id)
    return strdup_printf("%lld /* UNKNOWN */", reg_off);
 }
+static const char *vector_id_to_str(const char *prefix, __u64 id)
+{
+	/* reg_off is the offset into struct __riscv_v_ext_state */
+	__u64 reg_off = id & ~(REG_MASK | KVM_REG_RISCV_VECTOR);
+	int reg_index = 0;
+
+	assert((id & KVM_REG_RISCV_TYPE_MASK) == KVM_REG_RISCV_VECTOR);
+
+	if (reg_off >= KVM_REG_RISCV_VECTOR_REG(0))
+		reg_index = reg_off -  KVM_REG_RISCV_VECTOR_REG(0);
+	switch (reg_off) {
+	case KVM_REG_RISCV_VECTOR_REG(0) ...
+	     KVM_REG_RISCV_VECTOR_REG(31):
+		return strdup_printf("KVM_REG_RISCV_VECTOR_REG(%d)", reg_index);
+	case KVM_REG_RISCV_VECTOR_CSR_REG(vstart):
+		return "KVM_REG_RISCV_VECTOR_CSR_REG(vstart)";
+	case KVM_REG_RISCV_VECTOR_CSR_REG(vl):
+		return "KVM_REG_RISCV_VECTOR_CSR_REG(vl)";
+	case KVM_REG_RISCV_VECTOR_CSR_REG(vtype):
+		return "KVM_REG_RISCV_VECTOR_CSR_REG(vtype)";
+	case KVM_REG_RISCV_VECTOR_CSR_REG(vcsr):
+		return "KVM_RISCV_VCPU_VECTOR_CSR_REG(vcsr)";
+	case KVM_REG_RISCV_VECTOR_CSR_REG(vlenb):
+		return "KVM_REG_RISCV_VECTOR_CSR_REG(vlenb)";
+	}
+
+	return strdup_printf("%lld /* UNKNOWN */", reg_off);
+}
+
 #define KVM_ISA_EXT_ARR(ext)		\
 [KVM_RISCV_ISA_EXT_##ext] = "KVM_REG_RISCV_ISA_SINGLE | KVM_RISCV_ISA_EXT_" #ext
@@ -635,6 +683,9 @@ void print_reg(const char *prefix, __u64 id)
    case KVM_REG_SIZE_U128:
    	reg_size = "KVM_REG_SIZE_U128";
    	break;
+	case KVM_REG_SIZE_U256:
+		reg_size = "KVM_REG_SIZE_U256";
+		break;
    default:
    	printf("\tKVM_REG_RISCV | (%lld << KVM_REG_SIZE_SHIFT) | 0x%llx /* UNKNOWN */,\n",
    	       (id & KVM_REG_SIZE_MASK) >> KVM_REG_SIZE_SHIFT, id & ~REG_MASK);
@@ -666,6 +717,10 @@ void print_reg(const char *prefix, __u64 id)
    	printf("\tKVM_REG_RISCV | %s | KVM_REG_RISCV_FP_D | %s,\n",
    			reg_size, fp_d_id_to_str(prefix, id));
    	break;
+	case KVM_REG_RISCV_VECTOR:
+		printf("\tKVM_REG_RISCV | %s | KVM_REG_RISCV_VECTOR | %s,\n",
+		       reg_size, vector_id_to_str(prefix, id));
+		break;
    case KVM_REG_RISCV_ISA_EXT:
    	printf("\tKVM_REG_RISCV | %s | KVM_REG_RISCV_ISA_EXT | %s,\n",
    			reg_size, isa_ext_id_to_str(prefix, id));
@@ -870,6 +925,54 @@ static __u64 fp_d_regs[] = {
    KVM_REG_RISCV | KVM_REG_SIZE_ULONG | KVM_REG_RISCV_ISA_EXT | KVM_REG_RISCV_ISA_SINGLE | KVM_RISCV_ISA_EXT_D,
 };
+/* Define a default vector registers with length. This will be overwritten at runtime */
+static __u64 vector_regs[] = {
+	KVM_REG_RISCV | KVM_REG_SIZE_ULONG | KVM_REG_RISCV_VECTOR |
+	KVM_REG_RISCV_VECTOR_CSR_REG(vstart),
+	KVM_REG_RISCV | KVM_REG_SIZE_ULONG | KVM_REG_RISCV_VECTOR |
+	KVM_REG_RISCV_VECTOR_CSR_REG(vl),
+	KVM_REG_RISCV | KVM_REG_SIZE_ULONG | KVM_REG_RISCV_VECTOR |
+	KVM_REG_RISCV_VECTOR_CSR_REG(vtype),
+	KVM_REG_RISCV | KVM_REG_SIZE_ULONG | KVM_REG_RISCV_VECTOR |
+	KVM_REG_RISCV_VECTOR_CSR_REG(vcsr),
+	KVM_REG_RISCV | KVM_REG_SIZE_ULONG | KVM_REG_RISCV_VECTOR |
+	KVM_REG_RISCV_VECTOR_CSR_REG(vlenb),
+	KVM_REG_RISCV | KVM_REG_SIZE_U128 | KVM_REG_RISCV_VECTOR | KVM_REG_RISCV_VECTOR_REG(0),
+	KVM_REG_RISCV | KVM_REG_SIZE_U128 | KVM_REG_RISCV_VECTOR | KVM_REG_RISCV_VECTOR_REG(1),
+	KVM_REG_RISCV | KVM_REG_SIZE_U128 | KVM_REG_RISCV_VECTOR | KVM_REG_RISCV_VECTOR_REG(2),
+	KVM_REG_RISCV | KVM_REG_SIZE_U128 | KVM_REG_RISCV_VECTOR | KVM_REG_RISCV_VECTOR_REG(3),
+	KVM_REG_RISCV | KVM_REG_SIZE_U128 | KVM_REG_RISCV_VECTOR | KVM_REG_RISCV_VECTOR_REG(4),
+	KVM_REG_RISCV | KVM_REG_SIZE_U128 | KVM_REG_RISCV_VECTOR | KVM_REG_RISCV_VECTOR_REG(5),
+	KVM_REG_RISCV | KVM_REG_SIZE_U128 | KVM_REG_RISCV_VECTOR | KVM_REG_RISCV_VECTOR_REG(6),
+	KVM_REG_RISCV | KVM_REG_SIZE_U128 | KVM_REG_RISCV_VECTOR | KVM_REG_RISCV_VECTOR_REG(7),
+	KVM_REG_RISCV | KVM_REG_SIZE_U128 | KVM_REG_RISCV_VECTOR | KVM_REG_RISCV_VECTOR_REG(8),
+	KVM_REG_RISCV | KVM_REG_SIZE_U128 | KVM_REG_RISCV_VECTOR | KVM_REG_RISCV_VECTOR_REG(9),
+	KVM_REG_RISCV | KVM_REG_SIZE_U128 | KVM_REG_RISCV_VECTOR | KVM_REG_RISCV_VECTOR_REG(10),
+	KVM_REG_RISCV | KVM_REG_SIZE_U128 | KVM_REG_RISCV_VECTOR | KVM_REG_RISCV_VECTOR_REG(11),
+	KVM_REG_RISCV | KVM_REG_SIZE_U128 | KVM_REG_RISCV_VECTOR | KVM_REG_RISCV_VECTOR_REG(12),
+	KVM_REG_RISCV | KVM_REG_SIZE_U128 | KVM_REG_RISCV_VECTOR | KVM_REG_RISCV_VECTOR_REG(13),
+	KVM_REG_RISCV | KVM_REG_SIZE_U128 | KVM_REG_RISCV_VECTOR | KVM_REG_RISCV_VECTOR_REG(14),
+	KVM_REG_RISCV | KVM_REG_SIZE_U128 | KVM_REG_RISCV_VECTOR | KVM_REG_RISCV_VECTOR_REG(15),
+	KVM_REG_RISCV | KVM_REG_SIZE_U128 | KVM_REG_RISCV_VECTOR | KVM_REG_RISCV_VECTOR_REG(16),
+	KVM_REG_RISCV | KVM_REG_SIZE_U128 | KVM_REG_RISCV_VECTOR | KVM_REG_RISCV_VECTOR_REG(17),
+	KVM_REG_RISCV | KVM_REG_SIZE_U128 | KVM_REG_RISCV_VECTOR | KVM_REG_RISCV_VECTOR_REG(18),
+	KVM_REG_RISCV | KVM_REG_SIZE_U128 | KVM_REG_RISCV_VECTOR | KVM_REG_RISCV_VECTOR_REG(19),
+	KVM_REG_RISCV | KVM_REG_SIZE_U128 | KVM_REG_RISCV_VECTOR | KVM_REG_RISCV_VECTOR_REG(20),
+	KVM_REG_RISCV | KVM_REG_SIZE_U128 | KVM_REG_RISCV_VECTOR | KVM_REG_RISCV_VECTOR_REG(21),
+	KVM_REG_RISCV | KVM_REG_SIZE_U128 | KVM_REG_RISCV_VECTOR | KVM_REG_RISCV_VECTOR_REG(22),
+	KVM_REG_RISCV | KVM_REG_SIZE_U128 | KVM_REG_RISCV_VECTOR | KVM_REG_RISCV_VECTOR_REG(23),
+	KVM_REG_RISCV | KVM_REG_SIZE_U128 | KVM_REG_RISCV_VECTOR | KVM_REG_RISCV_VECTOR_REG(24),
+	KVM_REG_RISCV | KVM_REG_SIZE_U128 | KVM_REG_RISCV_VECTOR | KVM_REG_RISCV_VECTOR_REG(25),
+	KVM_REG_RISCV | KVM_REG_SIZE_U128 | KVM_REG_RISCV_VECTOR | KVM_REG_RISCV_VECTOR_REG(26),
+	KVM_REG_RISCV | KVM_REG_SIZE_U128 | KVM_REG_RISCV_VECTOR | KVM_REG_RISCV_VECTOR_REG(27),
+	KVM_REG_RISCV | KVM_REG_SIZE_U128 | KVM_REG_RISCV_VECTOR | KVM_REG_RISCV_VECTOR_REG(28),
+	KVM_REG_RISCV | KVM_REG_SIZE_U128 | KVM_REG_RISCV_VECTOR | KVM_REG_RISCV_VECTOR_REG(29),
+	KVM_REG_RISCV | KVM_REG_SIZE_U128 | KVM_REG_RISCV_VECTOR | KVM_REG_RISCV_VECTOR_REG(30),
+	KVM_REG_RISCV | KVM_REG_SIZE_U128 | KVM_REG_RISCV_VECTOR | KVM_REG_RISCV_VECTOR_REG(31),
+	KVM_REG_RISCV | KVM_REG_SIZE_ULONG | KVM_REG_RISCV_ISA_EXT | KVM_REG_RISCV_ISA_SINGLE |
+	KVM_RISCV_ISA_EXT_V,
+};
+
 #define SUBLIST_BASE \
    {"base", .regs = base_regs, .regs_n = ARRAY_SIZE(base_regs), \
     .skips_set = base_skips_set, .skips_set_n = ARRAY_SIZE(base_skips_set),}
@@ -894,6 +997,10 @@ static __u64 fp_d_regs[] = {
    {"fp_d", .feature = KVM_RISCV_ISA_EXT_D, .regs = fp_d_regs, \
    	.regs_n = ARRAY_SIZE(fp_d_regs),}
+#define SUBLIST_V \
+	{"v", .feature = KVM_RISCV_ISA_EXT_V, .regs = vector_regs, \
+		.regs_n = ARRAY_SIZE(vector_regs),}
+
 #define KVM_ISA_EXT_SIMPLE_CONFIG(ext, extu)			\
 static __u64 regs_##ext[] = {					\
    KVM_REG_RISCV | KVM_REG_SIZE_ULONG |			\
@@ -962,6 +1069,7 @@ KVM_SBI_EXT_SIMPLE_CONFIG(susp, SUSP);
 KVM_ISA_EXT_SUBLIST_CONFIG(aia, AIA);
 KVM_ISA_EXT_SUBLIST_CONFIG(fp_f, FP_F);
 KVM_ISA_EXT_SUBLIST_CONFIG(fp_d, FP_D);
+KVM_ISA_EXT_SUBLIST_CONFIG(v, V);
 KVM_ISA_EXT_SIMPLE_CONFIG(h, H);
 KVM_ISA_EXT_SIMPLE_CONFIG(smnpm, SMNPM);
 KVM_ISA_EXT_SUBLIST_CONFIG(smstateen, SMSTATEEN);
@@ -1034,6 +1142,7 @@ struct vcpu_reg_list *vcpu_configs[] = {
    &config_fp_f,
    &config_fp_d,
    &config_h,
+	&config_v,
    &config_smnpm,
    &config_smstateen,
    &config_sscofpmf,
-- 
2.43.0



    

2025

2024

2023

2022

2021

2020

2019

2018

2017

[PATCH 3/3] KVM: riscv: selftests: Add vector extension tests