lib: Factor-out SBI vendor extension

This patch factor-out SBI vendor extension into its own source
for better modularity of SBI implementation.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

lib/sbi/sbi_ecall_vendor.c

@@ -0,0 +1,40 @@
+/*
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2020 Western Digital Corporation or its affiliates.
+ *
+ * Authors:
+ *   Anup Patel <anup.patel@wdc.com>
+ *   Atish Patra <atish.patra@wdc.com>
+ */
+
+#include <sbi/sbi_ecall.h>
+#include <sbi/sbi_ecall_interface.h>
+#include <sbi/sbi_error.h>
+#include <sbi/sbi_platform.h>
+
+static int sbi_ecall_vendor_probe(struct sbi_scratch *scratch,
+				  unsigned long extid,
+				  unsigned long *out_val)
+{
+	*out_val = sbi_platform_vendor_ext_check(sbi_platform_ptr(scratch),
+						 extid);
+	return 0;
+}
+
+static int sbi_ecall_vendor_handler(struct sbi_scratch *scratch,
+				    unsigned long extid, unsigned long funcid,
+				    unsigned long *args, unsigned long *out_val,
+				    struct sbi_trap_info *out_trap)
+{
+	return sbi_platform_vendor_ext_provider(sbi_platform_ptr(scratch),
+						extid, funcid, args,
+						out_val, out_trap);
+}
+
+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,
+};