diff --git a/include/sbi/sbi_ecall.h b/include/sbi/sbi_ecall.h
index ff9bf8e..fac2642 100644
--- a/include/sbi/sbi_ecall.h
+++ b/include/sbi/sbi_ecall.h
@@ -24,6 +24,7 @@
 	struct sbi_dlist head;
 	unsigned long extid_start;
 	unsigned long extid_end;
+	int (* register_extensions)(void);
 	int (* probe)(unsigned long extid, unsigned long *out_val);
 	int (* handle)(unsigned long extid, unsigned long funcid,
 		       const struct sbi_trap_regs *regs,
diff --git a/lib/sbi/sbi_ecall.c b/lib/sbi/sbi_ecall.c
index 76a1ae9..3eb4f0a 100644
--- a/lib/sbi/sbi_ecall.c
+++ b/lib/sbi/sbi_ecall.c
@@ -154,7 +154,10 @@
 
 	for (i = 0; i < sbi_ecall_exts_size; i++) {
 		ext = sbi_ecall_exts[i];
-		ret = sbi_ecall_register_extension(ext);
+		ret = SBI_ENODEV;
+
+		if (ext->register_extensions)
+			ret = ext->register_extensions();
 		if (ret)
 			return ret;
 	}
diff --git a/lib/sbi/sbi_ecall_base.c b/lib/sbi/sbi_ecall_base.c
index 786d2ac..74f05eb 100644
--- a/lib/sbi/sbi_ecall_base.c
+++ b/lib/sbi/sbi_ecall_base.c
@@ -72,8 +72,16 @@
 	return ret;
 }
 
+struct sbi_ecall_extension ecall_base;
+
+static int sbi_ecall_base_register_extensions(void)
+{
+	return sbi_ecall_register_extension(&ecall_base);
+}
+
 struct sbi_ecall_extension ecall_base = {
-	.extid_start = SBI_EXT_BASE,
-	.extid_end = SBI_EXT_BASE,
-	.handle = sbi_ecall_base_handler,
+	.extid_start		= SBI_EXT_BASE,
+	.extid_end		= SBI_EXT_BASE,
+	.register_extensions	= sbi_ecall_base_register_extensions,
+	.handle			= sbi_ecall_base_handler,
 };
diff --git a/lib/sbi/sbi_ecall_cppc.c b/lib/sbi/sbi_ecall_cppc.c
index 91585f3..42ec744 100644
--- a/lib/sbi/sbi_ecall_cppc.c
+++ b/lib/sbi/sbi_ecall_cppc.c
@@ -55,9 +55,17 @@
 	return 0;
 }
 
+struct sbi_ecall_extension ecall_cppc;
+
+static int sbi_ecall_cppc_register_extensions(void)
+{
+	return sbi_ecall_register_extension(&ecall_cppc);
+}
+
 struct sbi_ecall_extension ecall_cppc = {
-	.extid_start	= SBI_EXT_CPPC,
-	.extid_end	= SBI_EXT_CPPC,
-	.handle		= sbi_ecall_cppc_handler,
-	.probe		= sbi_ecall_cppc_probe,
+	.extid_start		= SBI_EXT_CPPC,
+	.extid_end		= SBI_EXT_CPPC,
+	.register_extensions	= sbi_ecall_cppc_register_extensions,
+	.probe			= sbi_ecall_cppc_probe,
+	.handle			= sbi_ecall_cppc_handler,
 };
diff --git a/lib/sbi/sbi_ecall_dbcn.c b/lib/sbi/sbi_ecall_dbcn.c
index fe7e175..58b19e4 100644
--- a/lib/sbi/sbi_ecall_dbcn.c
+++ b/lib/sbi/sbi_ecall_dbcn.c
@@ -64,9 +64,17 @@
 	return 0;
 }
 
+struct sbi_ecall_extension ecall_dbcn;
+
+static int sbi_ecall_dbcn_register_extensions(void)
+{
+	return sbi_ecall_register_extension(&ecall_dbcn);
+}
+
 struct sbi_ecall_extension ecall_dbcn = {
-	.extid_start = SBI_EXT_DBCN,
-	.extid_end = SBI_EXT_DBCN,
-	.handle = sbi_ecall_dbcn_handler,
-	.probe = sbi_ecall_dbcn_probe,
+	.extid_start		= SBI_EXT_DBCN,
+	.extid_end		= SBI_EXT_DBCN,
+	.register_extensions	= sbi_ecall_dbcn_register_extensions,
+	.probe			= sbi_ecall_dbcn_probe,
+	.handle			= sbi_ecall_dbcn_handler,
 };
diff --git a/lib/sbi/sbi_ecall_hsm.c b/lib/sbi/sbi_ecall_hsm.c
index f1b41d0..20705c3 100644
--- a/lib/sbi/sbi_ecall_hsm.c
+++ b/lib/sbi/sbi_ecall_hsm.c
@@ -54,8 +54,16 @@
 	return ret;
 }
 
+struct sbi_ecall_extension ecall_hsm;
+
+static int sbi_ecall_hsm_register_extensions(void)
+{
+	return sbi_ecall_register_extension(&ecall_hsm);
+}
+
 struct sbi_ecall_extension ecall_hsm = {
-	.extid_start = SBI_EXT_HSM,
-	.extid_end = SBI_EXT_HSM,
-	.handle = sbi_ecall_hsm_handler,
+	.extid_start		= SBI_EXT_HSM,
+	.extid_end		= SBI_EXT_HSM,
+	.register_extensions	= sbi_ecall_hsm_register_extensions,
+	.handle			= sbi_ecall_hsm_handler,
 };
diff --git a/lib/sbi/sbi_ecall_ipi.c b/lib/sbi/sbi_ecall_ipi.c
index f4797e1..a40d6b8 100644
--- a/lib/sbi/sbi_ecall_ipi.c
+++ b/lib/sbi/sbi_ecall_ipi.c
@@ -29,8 +29,16 @@
 	return ret;
 }
 
+struct sbi_ecall_extension ecall_ipi;
+
+static int sbi_ecall_ipi_register_extensions(void)
+{
+	return sbi_ecall_register_extension(&ecall_ipi);
+}
+
 struct sbi_ecall_extension ecall_ipi = {
-	.extid_start = SBI_EXT_IPI,
-	.extid_end = SBI_EXT_IPI,
-	.handle = sbi_ecall_ipi_handler,
+	.extid_start		= SBI_EXT_IPI,
+	.extid_end		= SBI_EXT_IPI,
+	.register_extensions	= sbi_ecall_ipi_register_extensions,
+	.handle			= sbi_ecall_ipi_handler,
 };
diff --git a/lib/sbi/sbi_ecall_legacy.c b/lib/sbi/sbi_ecall_legacy.c
index 8237498..99e862e 100644
--- a/lib/sbi/sbi_ecall_legacy.c
+++ b/lib/sbi/sbi_ecall_legacy.c
@@ -117,8 +117,16 @@
 	return ret;
 }
 
+struct sbi_ecall_extension ecall_legacy;
+
+static int sbi_ecall_legacy_register_extensions(void)
+{
+	return sbi_ecall_register_extension(&ecall_legacy);
+}
+
 struct sbi_ecall_extension ecall_legacy = {
-	.extid_start = SBI_EXT_0_1_SET_TIMER,
-	.extid_end = SBI_EXT_0_1_SHUTDOWN,
-	.handle = sbi_ecall_legacy_handler,
+	.extid_start		= SBI_EXT_0_1_SET_TIMER,
+	.extid_end		= SBI_EXT_0_1_SHUTDOWN,
+	.register_extensions	= sbi_ecall_legacy_register_extensions,
+	.handle			= sbi_ecall_legacy_handler,
 };
diff --git a/lib/sbi/sbi_ecall_pmu.c b/lib/sbi/sbi_ecall_pmu.c
index 367e927..b0589d0 100644
--- a/lib/sbi/sbi_ecall_pmu.c
+++ b/lib/sbi/sbi_ecall_pmu.c
@@ -88,9 +88,17 @@
 	return 0;
 }
 
+struct sbi_ecall_extension ecall_pmu;
+
+static int sbi_ecall_pmu_register_extensions(void)
+{
+	return sbi_ecall_register_extension(&ecall_pmu);
+}
+
 struct sbi_ecall_extension ecall_pmu = {
-	.extid_start = SBI_EXT_PMU,
-	.extid_end = SBI_EXT_PMU,
-	.handle = sbi_ecall_pmu_handler,
-	.probe = sbi_ecall_pmu_probe,
+	.extid_start		= SBI_EXT_PMU,
+	.extid_end		= SBI_EXT_PMU,
+	.register_extensions	= sbi_ecall_pmu_register_extensions,
+	.probe			= sbi_ecall_pmu_probe,
+	.handle			= sbi_ecall_pmu_handler,
 };
diff --git a/lib/sbi/sbi_ecall_rfence.c b/lib/sbi/sbi_ecall_rfence.c
index 6334c00..22c6652 100644
--- a/lib/sbi/sbi_ecall_rfence.c
+++ b/lib/sbi/sbi_ecall_rfence.c
@@ -79,8 +79,16 @@
 	return ret;
 }
 
+struct sbi_ecall_extension ecall_rfence;
+
+static int sbi_ecall_rfence_register_extensions(void)
+{
+	return sbi_ecall_register_extension(&ecall_rfence);
+}
+
 struct sbi_ecall_extension ecall_rfence = {
-	.extid_start = SBI_EXT_RFENCE,
-	.extid_end = SBI_EXT_RFENCE,
-	.handle = sbi_ecall_rfence_handler,
+	.extid_start		= SBI_EXT_RFENCE,
+	.extid_end		= SBI_EXT_RFENCE,
+	.register_extensions	= sbi_ecall_rfence_register_extensions,
+	.handle			= sbi_ecall_rfence_handler,
 };
diff --git a/lib/sbi/sbi_ecall_srst.c b/lib/sbi/sbi_ecall_srst.c
index 93b012c..ad31537 100644
--- a/lib/sbi/sbi_ecall_srst.c
+++ b/lib/sbi/sbi_ecall_srst.c
@@ -67,9 +67,17 @@
 	return 0;
 }
 
+struct sbi_ecall_extension ecall_srst;
+
+static int sbi_ecall_srst_register_extensions(void)
+{
+	return sbi_ecall_register_extension(&ecall_srst);
+}
+
 struct sbi_ecall_extension ecall_srst = {
-	.extid_start = SBI_EXT_SRST,
-	.extid_end = SBI_EXT_SRST,
-	.handle = sbi_ecall_srst_handler,
-	.probe = sbi_ecall_srst_probe,
+	.extid_start		= SBI_EXT_SRST,
+	.extid_end		= SBI_EXT_SRST,
+	.register_extensions	= sbi_ecall_srst_register_extensions,
+	.probe			= sbi_ecall_srst_probe,
+	.handle			= sbi_ecall_srst_handler,
 };
diff --git a/lib/sbi/sbi_ecall_susp.c b/lib/sbi/sbi_ecall_susp.c
index f20126c..bfbdbe6 100644
--- a/lib/sbi/sbi_ecall_susp.c
+++ b/lib/sbi/sbi_ecall_susp.c
@@ -40,9 +40,17 @@
 	return 0;
 }
 
+struct sbi_ecall_extension ecall_susp;
+
+static int sbi_ecall_susp_register_extensions(void)
+{
+	return sbi_ecall_register_extension(&ecall_susp);
+}
+
 struct sbi_ecall_extension ecall_susp = {
-	.extid_start = SBI_EXT_SUSP,
-	.extid_end = SBI_EXT_SUSP,
-	.handle = sbi_ecall_susp_handler,
-	.probe = sbi_ecall_susp_probe,
+	.extid_start		= SBI_EXT_SUSP,
+	.extid_end		= SBI_EXT_SUSP,
+	.register_extensions	= sbi_ecall_susp_register_extensions,
+	.probe			= sbi_ecall_susp_probe,
+	.handle			= sbi_ecall_susp_handler,
 };
diff --git a/lib/sbi/sbi_ecall_time.c b/lib/sbi/sbi_ecall_time.c
index 668cb17..e79196f 100644
--- a/lib/sbi/sbi_ecall_time.c
+++ b/lib/sbi/sbi_ecall_time.c
@@ -33,8 +33,16 @@
 	return ret;
 }
 
+struct sbi_ecall_extension ecall_time;
+
+static int sbi_ecall_time_register_extensions(void)
+{
+	return sbi_ecall_register_extension(&ecall_time);
+}
+
 struct sbi_ecall_extension ecall_time = {
-	.extid_start = SBI_EXT_TIME,
-	.extid_end = SBI_EXT_TIME,
-	.handle = sbi_ecall_time_handler,
+	.extid_start		= SBI_EXT_TIME,
+	.extid_end		= SBI_EXT_TIME,
+	.register_extensions	= sbi_ecall_time_register_extensions,
+	.handle			= sbi_ecall_time_handler,
 };
diff --git a/lib/sbi/sbi_ecall_vendor.c b/lib/sbi/sbi_ecall_vendor.c
index 8b8dab0..126156f 100644
--- a/lib/sbi/sbi_ecall_vendor.c
+++ b/lib/sbi/sbi_ecall_vendor.c
@@ -47,9 +47,17 @@
 						out_val, out_trap);
 }
 
+struct sbi_ecall_extension ecall_vendor;
+
+static int sbi_ecall_vendor_register_extensions(void)
+{
+	return sbi_ecall_register_extension(&ecall_vendor);
+}
+
 struct sbi_ecall_extension ecall_vendor = {
-	.extid_start = SBI_EXT_VENDOR_START,
-	.extid_end = SBI_EXT_VENDOR_END,
-	.probe = sbi_ecall_vendor_probe,
-	.handle = sbi_ecall_vendor_handler,
+	.extid_start		= SBI_EXT_VENDOR_START,
+	.extid_end		= SBI_EXT_VENDOR_END,
+	.register_extensions	= sbi_ecall_vendor_register_extensions,
+	.probe			= sbi_ecall_vendor_probe,
+	.handle			= sbi_ecall_vendor_handler,
 };