lib: utils: Add FDT match table based node lookup

This patch adds FDT match table based node lookup funcitons.

These functions will be useful in implementing simple FDT
based driver frameworks.

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

2 files changed, 52 insertions, 0 deletions

diff --git a/include/sbi_utils/fdt/fdt_helper.h b/include/sbi_utils/fdt/fdt_helper.h
index 57c47201..a5254930 100644
--- a/include/sbi_utils/fdt/fdt_helper.h
+++ b/include/sbi_utils/fdt/fdt_helper.h
@@ -10,6 +10,11 @@
 #ifndef __FDT_HELPER_H__
 #define __FDT_HELPER_H__
 
+struct fdt_match {
+	const char *compatible;
+	void *data;
+};
+
 struct platform_uart_data {
 	unsigned long addr;
 	unsigned long freq;
@@ -23,6 +28,12 @@ struct platform_plic_data {
 	unsigned long num_src;
 };
 
+const struct fdt_match *fdt_match_node(void *fdt, int nodeoff,
+				       const struct fdt_match *match_table);
+
+int fdt_find_match(void *fdt, const struct fdt_match *match_table,
+		   const struct fdt_match **out_match);
+
 int fdt_parse_uart8250_node(void *fdt, int nodeoffset,
 			    struct platform_uart_data *uart);
 
diff --git a/lib/utils/fdt/fdt_helper.c b/lib/utils/fdt/fdt_helper.c
index 573cc71f..e8c927de 100644
--- a/lib/utils/fdt/fdt_helper.c
+++ b/lib/utils/fdt/fdt_helper.c
@@ -18,6 +18,47 @@
 #define DEFAULT_UART_REG_SHIFT		0
 #define DEFAULT_UART_REG_IO_WIDTH	1
 
+const struct fdt_match *fdt_match_node(void *fdt, int nodeoff,
+				       const struct fdt_match *match_table)
+{
+	int ret;
+
+	if (!fdt || nodeoff < 0 || !match_table)
+		return NULL;
+
+	while (match_table->compatible) {
+		ret = fdt_node_check_compatible(fdt, nodeoff,
+						match_table->compatible);
+		if (!ret)
+			return match_table;
+		match_table++;
+	}
+
+	return NULL;
+}
+
+int fdt_find_match(void *fdt, const struct fdt_match *match_table,
+		   const struct fdt_match **out_match)
+{
+	int nodeoff;
+
+	if (!fdt || !match_table)
+		return SBI_ENODEV;
+
+	while (match_table->compatible) {
+		nodeoff = fdt_node_offset_by_compatible(fdt, -1,
+						match_table->compatible);
+		if (nodeoff >= 0) {
+			if (out_match)
+				*out_match = match_table;
+			return nodeoff;
+		}
+		match_table++;
+	}
+
+	return SBI_ENODEV;
+}
+
 static int fdt_get_node_addr_size(void *fdt, int node, unsigned long *addr,
 				  unsigned long *size)
 {