From a668443bea3fa506fdd5bbc7f52ee703a6c5cf89 Mon Sep 17 00:00:00 2001
From: Mark Poliakov <mark@alnyan.me>
Date: Tue, 18 Mar 2025 09:51:41 +0200
Subject: [PATCH] dtb: make dtb struct more useful

---
 output.log       |  8 --------
 src/util/dtb.zig | 31 +++++++++++++++++++++++++++++++
 2 files changed, 31 insertions(+), 8 deletions(-)
 delete mode 100644 output.log

diff --git a/output.log b/output.log
deleted file mode 100644
index fff21f0..0000000
--- a/output.log
+++ /dev/null
@@ -1,8 +0,0 @@
-Hello, dtb is at 0x48000000
-Memory: 'memory@40000000', base 0x40000000, size 0x10000000
-Reserved: 'kernel', base 0x40080000, size 0x1d000
-Reserved: 'fdt', base 0x48000000, size 0x100000
-Reserved: 'page-array', base 0x4009d000, size 0x100000
-Available memory: 253 MiB, page array mem.phys.Page@4009d000
-QEMU: Terminated
-
\ No newline at end of file
diff --git a/src/util/dtb.zig b/src/util/dtb.zig
index 536fa14..ee2dc8f 100644
--- a/src/util/dtb.zig
+++ b/src/util/dtb.zig
@@ -88,6 +88,11 @@ pub const FdtNodeProp = struct {
         return .{ .prop = self };
     }
 
+    pub inline fn getString(self: *const @This()) []const u8 {
+        var sa = self.getStringArray();
+        return sa.next() orelse "";
+    }
+
     pub inline fn lenU32(self: *const @This()) usize {
         return self.value.len / @sizeOf(u32);
     }
@@ -382,6 +387,32 @@ pub const Fdt = struct {
         }
     }
 
+    pub fn find(self: *const @This(), path: []const u8) ?FdtNode {
+        const trimmedPath = std.mem.trimLeft(u8, path, "/");
+        var pathElements = std.mem.splitScalar(u8, trimmedPath, '/');
+        var currentNode = self.rootNode();
+        if (trimmedPath.len == 0) {
+            return currentNode;
+        }
+        while (pathElements.next()) |element| {
+            var found: ?FdtNode = null;
+            var children = currentNode.children();
+            while (children.next()) |child| {
+                if (std.mem.eql(u8, child.name, element)) {
+                    found = child;
+                    break;
+                }
+            }
+            if (found) |f| {
+                log.info("{s}", .{ element });
+                currentNode = f;
+            } else {
+                return null;
+            }
+        }
+        return currentNode;
+    }
+
     fn dump_property(property: *const FdtNodeProp, depth: usize, allStrings: bool) void {
         for (0..depth) |_| {
             log.writeRaw("  ");