2 files changed, 40 insertions, 0 deletions
diff --git a/tools/testing/selftests/kvm/include/riscv/processor.h b/tools/testing/selftests/kvm/include/riscv/processor.h
index e70ccda2011b..dc50ad62e150 100644
--- a/tools/testing/selftests/kvm/include/riscv/processor.h
+++ b/tools/testing/selftests/kvm/include/riscv/processor.h
@@ -108,6 +108,17 @@ static inline uint64_t __kvm_reg_id(uint64_t type, uint64_t subtype,
 #define SATP_ASID_SHIFT				44
 #define SATP_ASID_MASK				_AC(0xFFFF, UL)
 
+/* SBI return error codes */
+#define SBI_SUCCESS				0
+#define SBI_ERR_FAILURE				-1
+#define SBI_ERR_NOT_SUPPORTED			-2
+#define SBI_ERR_INVALID_PARAM			-3
+#define SBI_ERR_DENIED				-4
+#define SBI_ERR_INVALID_ADDRESS			-5
+#define SBI_ERR_ALREADY_AVAILABLE		-6
+#define SBI_ERR_ALREADY_STARTED			-7
+#define SBI_ERR_ALREADY_STOPPED			-8
+
 #define SBI_EXT_EXPERIMENTAL_START		0x08000000
 #define SBI_EXT_EXPERIMENTAL_END		0x08FFFFFF
 
@@ -115,6 +126,14 @@ static inline uint64_t __kvm_reg_id(uint64_t type, uint64_t subtype,
 #define KVM_RISCV_SELFTESTS_SBI_UCALL		0
 #define KVM_RISCV_SELFTESTS_SBI_UNEXP		1
 
+enum sbi_ext_id {
+	SBI_EXT_BASE = 0x10,
+};
+
+enum sbi_ext_base_fid {
+	SBI_EXT_BASE_PROBE_EXT = 3,
+};
+
 struct sbiret {
 	long error;
 	long value;
@@ -125,4 +144,6 @@ struct sbiret sbi_ecall(int ext, int fid, unsigned long arg0,
 			unsigned long arg3, unsigned long arg4,
 			unsigned long arg5);
 
+bool guest_sbi_probe_extension(int extid, long *out_val);
+
 #endif /* SELFTEST_KVM_PROCESSOR_H */
diff --git a/tools/testing/selftests/kvm/lib/riscv/processor.c b/tools/testing/selftests/kvm/lib/riscv/processor.c
index 6905a4348380..7ca736fb4194 100644
--- a/tools/testing/selftests/kvm/lib/riscv/processor.c
+++ b/tools/testing/selftests/kvm/lib/riscv/processor.c
@@ -393,3 +393,22 @@ struct sbiret sbi_ecall(int ext, int fid, unsigned long arg0,
 
 	return ret;
 }
+
+bool guest_sbi_probe_extension(int extid, long *out_val)
+{
+	struct sbiret ret;
+
+	ret = sbi_ecall(SBI_EXT_BASE, SBI_EXT_BASE_PROBE_EXT, extid,
+			0, 0, 0, 0, 0);
+
+	__GUEST_ASSERT(!ret.error || ret.error == SBI_ERR_NOT_SUPPORTED,
+		       "ret.error=%ld, ret.value=%ld\n", ret.error, ret.value);
+
+	if (ret.error == SBI_ERR_NOT_SUPPORTED)
+		return false;
+
+	if (out_val)
+		*out_val = ret.value;
+
+	return true;
+}