From 71ee41fe2c4c43dd745d6c9b6c2d7013f9450d63 Mon Sep 17 00:00:00 2001
From: Nik <werwolv98@gmail.com>
Date: Tue, 20 Dec 2022 17:14:23 +0100
Subject: [PATCH] patterns/fdt: Added flat device tree blob pattern

---
 README.md        |  1 +
 patterns/fdt.pat | 70 ++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 71 insertions(+)
 create mode 100644 patterns/fdt.pat

diff --git a/README.md b/README.md
index 522b309..ce8e643 100644
--- a/README.md
+++ b/README.md
@@ -49,6 +49,7 @@ Hex patterns, include patterns and magic files for the use with the ImHex Hex Ed
 | ID3 | `audio/mpeg` | [`patterns/id3tag.hexpat`](patterns/id3tag.hexpat) | ID3 tags in MP3 files |
 | TAR | `application/x-tar` | [`patterns/tar.hexpat`](patterns/tar.hexpat) | Tar file format |
 | CPIO | `application/x-cpio` | [`patterns/cpio.hexpat`](patterns/cpio.hexpat) | Old Binary CPIO Format |
+| FDT | | [`patterns/cpio.hexpat`](patterns/fdt.hexpat) | Flat Linux Device Tree blob |
 
 ### Scripts
 
diff --git a/patterns/fdt.pat b/patterns/fdt.pat
new file mode 100644
index 0000000..27fe0ea
--- /dev/null
+++ b/patterns/fdt.pat
@@ -0,0 +1,70 @@
+#pragma endian big
+
+#include <std/sys.pat>
+#include <std/io.pat>
+
+#include <type/magic.pat>
+#include <type/size.pat>
+
+struct FDTHeader {
+    type::Magic<"\xD0\x0D\xFE\xED"> magic;
+    u32 totalsize;
+    u32 off_dt_struct;
+    u32 off_dt_strings;
+    u32 off_mem_rsvmap;
+    u32 version;
+    u32 last_comp_version;
+    u32 boot_cpuid_phys;
+    u32 size_dt_strings;
+    u32 size_dt_struct;
+};
+
+struct AlignTo<auto Alignment> {
+    padding[Alignment- ((($ - 1) % Alignment) + 1)];
+};
+
+struct FDTReserveEntry {
+    u64 address;
+    type::Size<u64> size;
+    
+    if (address == 0x00 && size == 0x00)
+        break;
+};
+
+enum FDTToken : u32 {
+    FDT_BEGIN_NODE = 0x00000001,
+    FDT_END_NODE   = 0x00000002,
+    FDT_PROP       = 0x00000003,
+    FDT_NOP        = 0x00000004,
+    FDT_END        = 0x00000009
+};
+
+struct FDTStructureBlock {
+    FDTToken token;
+    if (token == FDTToken::FDT_BEGIN_NODE) {
+        char nodeName[];
+        AlignTo<4>;
+    } else if (token == FDTToken::FDT_END) {
+        break;
+    } else if (token == FDTToken::FDT_PROP) {
+        u32 len;
+        u32 nameoff;
+        char value[len];
+        AlignTo<4>;
+        char name[] @ parent.header.off_dt_strings + nameoff;
+    } else if (token == FDTToken::FDT_NOP || token == FDTToken::FDT_END_NODE) {
+        // Nothing to do
+    } else {
+        std::error(std::format("Invalid token at address 0x{:02X}", addressof(token)));
+    }
+};
+
+struct FDT {
+    FDTHeader header;
+    std::assert(header.version == 17, "Unsupported format version");
+    
+    FDTStructureBlock structureBlocks[while(true)] @ header.off_dt_struct;
+    FDTReserveEntry reserveEntries[while(true)] @ header.off_mem_rsvmap;
+};
+
+FDT fdt @ 0x00;
\ No newline at end of file