1 files changed, 76 insertions, 0 deletions
diff --git a/machine/fdt.h b/machine/fdt.h
new file mode 100644
index 0000000..d436778
--- /dev/null
+++ b/machine/fdt.h
@@ -0,0 +1,76 @@
+#ifndef FDT_H
+#define FDT_H
+
+#define FDT_MAGIC	0xd00dfeed
+#define FDT_VERSION	17
+
+struct fdt_header {
+  uint32_t magic;
+  uint32_t totalsize;
+  uint32_t off_dt_struct;
+  uint32_t off_dt_strings;
+  uint32_t off_mem_rsvmap;
+  uint32_t version;
+  uint32_t last_comp_version; /* <= 17 */
+  uint32_t boot_cpuid_phys;
+  uint32_t size_dt_strings;
+  uint32_t size_dt_struct;
+};
+
+#define FDT_BEGIN_NODE	1
+#define FDT_END_NODE	2
+#define FDT_PROP	3
+#define FDT_NOP		4
+#define FDT_END		9
+
+struct fdt_scan_node {
+  const struct fdt_scan_node *parent;
+  const char *name;
+  int address_cells;
+  int size_cells;
+};
+
+struct fdt_scan_prop {
+  const struct fdt_scan_node *node;
+  const char *name;
+  uint32_t *value;
+  int len; // in bytes of value
+};
+
+struct fdt_cb {
+  void (*open)(const struct fdt_scan_node *node, void *extra);
+  void (*prop)(const struct fdt_scan_prop *prop, void *extra);
+  void (*done)(const struct fdt_scan_node *node, void *extra); // last property was seen
+  int  (*close)(const struct fdt_scan_node *node, void *extra); // -1 => delete the node + children
+  void *extra;
+};
+
+// Scan the contents of FDT
+void fdt_scan(uintptr_t fdt, const struct fdt_cb *cb);
+uint32_t fdt_size(uintptr_t fdt);
+
+// Extract fields
+const uint32_t *fdt_get_address(const struct fdt_scan_node *node, const uint32_t *base, uint64_t *value);
+const uint32_t *fdt_get_size(const struct fdt_scan_node *node, const uint32_t *base, uint64_t *value);
+int fdt_string_list_index(const struct fdt_scan_prop *prop, const char *str); // -1 if not found
+
+// Setup memory+clint+plic
+void query_mem(uintptr_t fdt);
+void query_harts(uintptr_t fdt);
+void query_plic(uintptr_t fdt);
+void query_clint(uintptr_t fdt);
+
+// Remove information from FDT
+void filter_harts(uintptr_t fdt, long *disabled_hart_mask);
+void filter_plic(uintptr_t fdt);
+void filter_compat(uintptr_t fdt, const char *compat);
+
+// The hartids of available harts
+extern uint64_t hart_mask;
+
+#ifdef PK_PRINT_DEVICE_TREE
+// Prints the device tree to the console as a DTS
+void fdt_print(uintptr_t fdt);
+#endif
+
+#endif