riscv: function to retrieve SBI implementation version

Provide function sbi_get_impl_version() to retrieve the SBI implementation
version.

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Reviewed-by: Leo Yu-Chi Liang <ycliang@andestech.com>
Reviewed-by: Rick Chen <rick@andestech.com>

arch/riscv/include/asm/sbi.h

@@ -152,6 +152,7 @@ void sbi_remote_sfence_vma_asid(const unsigned long *hart_mask,
 void sbi_set_timer(uint64_t stime_value);
 long sbi_get_spec_version(void);
 int sbi_get_impl_id(void);
+int sbi_get_impl_version(long *version);
 int sbi_probe_extension(int ext);
 void sbi_srst_reset(unsigned long type, unsigned long reason);
 

arch/riscv/lib/sbi.c

@@ -89,6 +89,25 @@ int sbi_get_impl_id(void)
 	return -ENOTSUPP;
 }
 
+/**
+ * sbi_get_impl_version() - get SBI implementation version
+ *
+ * @version:	pointer to receive version
+ * Return:	0 on success, -ENOTSUPP otherwise
+ */
+int sbi_get_impl_version(long *version)
+{
+	struct sbiret ret;
+
+	ret = sbi_ecall(SBI_EXT_BASE, SBI_EXT_BASE_GET_IMP_VERSION,
+			0, 0, 0, 0, 0, 0);
+	if (ret.error)
+		return -ENOTSUPP;
+	if (version)
+		*version = ret.value;
+	return 0;
+}
+
 /**
  * sbi_probe_extension() - Check if an SBI extension ID is supported or not.
  * @extid: The extension ID to be probed.