use core::{iter, ptr::NonNull};
use crate::{
error::*, meta::MetaData, node::Node, read::FdtReader, FdtHeader, MemoryRegion, Phandle, Token,
};
#[derive(Clone)]
pub struct Fdt<'a> {
pub(crate) header: FdtHeader,
pub(crate) data: &'a [u8],
}
impl<'a> Fdt<'a> {
pub fn from_bytes(data: &'a [u8]) -> FdtResult<'a, Self> {
let header = FdtHeader::from_bytes(data)?;
header.valid_magic()?;
Ok(Self { header, data })
}
pub fn from_ptr(ptr: NonNull<u8>) -> FdtResult<'a, Self> {
let tmp_header =
unsafe { core::slice::from_raw_parts(ptr.as_ptr(), core::mem::size_of::<FdtHeader>()) };
let real_size = FdtHeader::from_bytes(tmp_header)?.totalsize.get() as usize;
Self::from_bytes(unsafe { core::slice::from_raw_parts(ptr.as_ptr(), real_size) })
}
fn reader(&'a self, offset: usize) -> FdtReader<'a> {
FdtReader::new(&self.data[offset..])
}
pub fn version(&self) -> usize {
self.header.version.get() as _
}
pub fn reserved_memory_regions(&self) -> impl Iterator<Item = MemoryRegion> + '_ {
let mut reader = self.reader(self.header.off_mem_rsvmap.get() as _);
iter::from_fn(move || match reader.reserved_memory() {
Some(region) => {
if region.address == 0 && region.size == 0 {
None
} else {
Some(region.into())
}
}
None => None,
})
}
pub(crate) fn get_str(&'a self, offset: usize) -> FdtResult<'a, &'a str> {
let string_bytes = &self.data[self.header.strings_range()];
let reader = FdtReader::new(&string_bytes[offset..]);
reader.peek_str()
}
pub fn all_nodes(&'a self) -> impl Iterator<Item = Node<'a>> {
let struct_bytes = &self.data[self.header.struct_range()];
let reader = FdtReader::new(struct_bytes);
FdtIter {
fdt: self,
current_level: 0,
reader,
stack: Default::default(),
node_reader: None,
node_name: "",
}
}
pub fn get_node_by_phandle(&'a self, phandle: Phandle) -> Option<Node<'a>> {
self.all_nodes()
.find(|x| match x.phandle() {
Some(p) => p.eq(&phandle),
None => false,
})
.clone()
}
pub fn get_node_by_name(&'a self, name: &str) -> Option<Node<'a>> {
self.all_nodes().find(|x| x.name().eq(name)).clone()
}
pub fn find_compatible(&'a self, with: &[&str]) -> Option<Node<'a>> {
self.all_nodes().find(|n| {
n.compatible()
.and_then(|mut compats| {
compats.find(|c| match c {
Ok(c) => with.contains(c),
Err(_) => false,
})
})
.is_some()
})
}
pub fn find_node(&'a self, path: &str) -> Option<Node<'a>> {
if path.starts_with("/") {
let mut out = None;
let mut parts = path.split("/").filter(|o| !o.is_empty());
let mut want = "/";
for node in self.all_nodes() {
let eq = if path.contains("@") {
node.name.eq(want)
} else {
let name = node.name.split("@").next().unwrap();
name.eq(want)
};
if eq {
out = Some(node.clone());
want = match parts.next() {
Some(t) => {
out = None;
t
}
None => return out,
};
}
}
out
} else {
let aliases = self.find_node("/aliases")?;
for prop in aliases.propertys() {
if prop.name.eq(path) {
let path = prop.str();
return self.find_node(path);
}
}
None
}
}
pub fn find_aliase(&'a self, name: &str) -> Option<&'a str> {
let aliases = self.find_node("/aliases")?;
for prop in aliases.propertys() {
if prop.name.eq(name) {
return Some(prop.str());
}
}
None
}
}
pub struct FdtIter<'a> {
fdt: &'a Fdt<'a>,
current_level: usize,
reader: FdtReader<'a>,
stack: [MetaData<'a>; 12],
node_reader: Option<FdtReader<'a>>,
node_name: &'a str,
}
impl<'a> FdtIter<'a> {
fn get_meta_parent(&self) -> MetaData<'a> {
let mut meta = MetaData::default();
let level = match self.level_parent_index() {
Some(l) => l,
None => return MetaData::default(),
} + 1;
macro_rules! get_field {
($cell:ident) => {{
let mut size = None;
for i in (0..level).rev() {
if let Some(cell_size) = &self.stack[i].$cell {
size = Some(cell_size.clone());
break;
}
}
meta.$cell = size;
}};
}
get_field!(address_cells);
get_field!(size_cells);
get_field!(clock_cells);
get_field!(interrupt_cells);
get_field!(gpio_cells);
get_field!(dma_cells);
get_field!(cooling_cells);
get_field!(range);
get_field!(interrupt_parent);
meta
}
fn level_current_index(&self) -> usize {
self.current_level - 1
}
fn level_parent_index(&self) -> Option<usize> {
if self.level_current_index() > 0 {
Some(self.level_current_index() - 1)
} else {
None
}
}
fn handle_node_begin(&mut self) {
self.current_level += 1;
let i = self.level_current_index();
self.stack[i] = MetaData::default();
self.node_name = self.reader.take_unit_name().unwrap();
self.node_reader = Some(self.reader.clone());
}
fn finish_node(&mut self) -> Option<Node<'a>> {
let reader = self.node_reader.take()?;
let level = self.current_level;
let meta = self.stack[self.level_current_index()].clone();
let meta_parent = self.get_meta_parent();
let mut node = Node::new(self.fdt, level, self.node_name, reader, meta_parent, meta);
let ranges = node.node_ranges();
self.stack[self.level_current_index()].range = ranges.clone();
self.stack[self.level_current_index()].interrupt_parent = node.node_interrupt_parent();
node.meta.range = ranges;
Some(node)
}
}
impl<'a> Iterator for FdtIter<'a> {
type Item = Node<'a>;
fn next(&mut self) -> Option<Self::Item> {
loop {
let token = self.reader.take_token()?;
match token {
Token::BeginNode => {
let node = self.finish_node();
self.handle_node_begin();
if node.is_some() {
return node;
}
}
Token::EndNode => {
let node = self.finish_node();
self.current_level -= 1;
if node.is_some() {
return node;
}
}
Token::Prop => {
let prop = self.reader.take_prop(self.fdt)?;
let index = self.level_current_index();
macro_rules! update_cell {
($cell:ident) => {
self.stack[index].$cell = Some(prop.u32() as _)
};
}
match prop.name {
"#address-cells" => update_cell!(address_cells),
"#size-cells" => update_cell!(size_cells),
"#clock-cells" => update_cell!(clock_cells),
"#interrupt-cells" => update_cell!(interrupt_cells),
"#gpio-cells" => update_cell!(gpio_cells),
"#dma-cells" => update_cell!(dma_cells),
"#cooling-cells" => update_cell!(cooling_cells),
_ => {}
}
}
Token::End => {
return self.finish_node();
}
_ => {}
}
}
}
}