make FDT handling more sane

kernel/src/arch/riscv64/csr.rs

@@ -134,9 +134,9 @@ pub mod satp {
     }
     pub fn read() -> Satp {
         let satp = unsafe { csrr!("satp") };
-        let mode = unsafe { transmute(bits!(satp;60,63)) };
+        let mode = unsafe { transmute::<u64, Mode>(bits!(satp;60,63)) };
         let asid = bits!(satp;44,59);
-        let ppn = unsafe { transmute(bits!(satp;0,43) << 12) };
+        let ppn = (bits!(satp;0,43) << 12) as *mut Table;
         Satp { mode, asid, ppn }
     }
     pub fn write(satp: Satp) {

kernel/src/arch/riscv64/init.rs

@@ -65,7 +65,7 @@ pub unsafe fn init() -> ! {
     }
     interrupts::init();
     let fdt = FDT::from_addr(dt_addr);
-    let raw_mem_range = fdt.mem_range();
+    let raw_mem_range = fdt.mem_range().expect("we lost guys");
     let heap_start = paging::init(raw_mem_range.end());
     let heap_mem = Range {
         start: heap_start,

kernel/src/arch/riscv64/paging.rs

@@ -27,7 +27,7 @@ impl Entry {
     }
     pub fn set_addr(&mut self, addr: usize) {
         self.clear();
-        self.0 |= addr as usize >> 2;
+        self.0 |= addr >> 2;
         self.0 |= 0b1110;
         self.set_valid(true);
     }
@@ -94,8 +94,7 @@ pub fn init(mem_end: *mut u8) -> *mut u8 {
             asid: 0,
             ppn: lvl2,
         });
-        let table_end = lvl0_arr.as_ptr().add(lvl0_arr.len()) as *mut u8;
-        table_end
+        lvl0_arr.as_ptr().add(lvl0_arr.len()) as *mut u8
     }
 }
 
@@ -104,13 +103,11 @@ pub fn virt_to_physical(table: &Table, addr: usize) -> usize {
     let ppn1 = bits!(addr;21,29);
     let ppn0 = bits!(addr;12,20);
     let offset = bits!(addr;0,11);
-    // let satp = csr::satp::read();
     unsafe {
         let lvl2 = table as *const Table;
         let lvl1 = (*lvl2).entries[ppn2].get_table();
         let lvl0 = (*lvl1).entries[ppn1].get_table();
         let base = (*lvl0).entries[ppn0].get_addr();
-        let addr = base + offset;
-        addr
+        base + offset
     }
 }

kernel/src/dev/fdt.rs

@@ -69,6 +69,9 @@ impl FDT {
             strings: self.strings,
         }
     }
+    pub fn root(&self) -> Option<Node> {
+        self.nodes().next()
+    }
     pub unsafe fn from_addr(addr: *mut u8) -> Self {
         let header: &Header = &*(addr as *const Header);
         if header.magic.get() != MAGIC {
@@ -111,7 +114,7 @@ impl Node {
         }
     }
     pub fn child(&self, name: &str) -> Option<Node> {
-        self.children().find(|c| c.name == name)
+        self.children().find(|c| c.name() == name)
     }
     pub fn props(&self) -> PropIter {
         PropIter {
@@ -122,6 +125,12 @@ impl Node {
     pub fn prop(&self, name: &str) -> Option<Prop> {
         self.props().find(|p| p.name == name)
     }
+    pub fn name(&self) -> &str {
+        self.name.split_once('@').map(|(name, _)| name).unwrap_or(self.name)
+    }
+    pub fn address(&self) -> Option<&str> {
+        self.name.split_once('@').map(|(_, addr)| Some(addr)).unwrap_or(None)
+    }
 }
 
 pub struct Prop {
@@ -152,17 +161,21 @@ pub struct PropIter {
 impl Iterator for PropIter {
     type Item = Prop;
     fn next(&mut self) -> Option<Self::Item> {
+        // make sure this is a prop
         let token: Token = Token::from_bytes(self.pos)?;
         let Token::Prop = token else {
             return None;
         };
         self.pos = &self.pos[4..];
+        // get raw info
         let prop: &RawProp = unsafe { &*(self.pos.as_ptr() as *const RawProp) };
         self.pos = &self.pos[PROP_SIZE..];
+        // get data
         let plen = prop.len.get() as usize;
         let len = (plen + (TOKEN_SIZE - 1)) & !(TOKEN_SIZE - 1);
         let data = &self.pos[..len];
         self.pos = &self.pos[len..];
+        // get name
         let name_start = &self.strings[prop.nameoff.get() as usize..];
         for (i, c) in name_start.iter().enumerate() {
             if *c == 0 {
@@ -176,6 +189,8 @@ impl Iterator for PropIter {
 }
 
 pub struct NodeIter {
+    // I should make a type called ByteCursor or something for this
+    // so dealing with it is not cursed and dependent on data type
     pub pos: &'static [u8],
     pub strings: &'static [u8],
 }
@@ -183,6 +198,7 @@ pub struct NodeIter {
 impl Iterator for NodeIter {
     type Item = Node;
     fn next(&mut self) -> Option<Self::Item> {
+        // first make sure this is actually a node
         if self.pos.is_empty() {
             return None;
         }
@@ -191,6 +207,7 @@ impl Iterator for NodeIter {
             return None;
         };
         self.pos = &self.pos[4..];
+        // then get the name
         let name_start = self.pos;
         let extra;
         'outer: loop {
@@ -205,6 +222,7 @@ impl Iterator for NodeIter {
         }
         let name = core::str::from_utf8(&name_start[..name_start.len() - self.pos.len() - extra])
             .expect("har har har har har har har har har har. RAAAAAAAAAAAAAAAAAAAAAAAA");
+        // then props
         let node_start = self.pos;
         let node_data = if let Some(prop) = (PropIter {
             strings: self.strings,
@@ -219,6 +237,7 @@ impl Iterator for NodeIter {
         } else {
             &[]
         };
+        // then children
         let children = match Token::from_bytes(self.pos) {
             Some(Token::EndNode | Token::End) => {
                 self.pos = &self.pos[4..];
@@ -230,19 +249,21 @@ impl Iterator for NodeIter {
                     pos: children,
                     strings: self.strings,
                 };
+                // skip children bytes
                 for _ in iter.by_ref() {}
                 self.pos = iter.pos;
                 match Token::from_bytes(self.pos) {
                     Some(Token::EndNode | Token::End) => self.pos = &self.pos[4..],
-                    _ => panic!("wut du heeeeell (toaken)"),
+                    _ => panic!("wut du heeeeeal (toaken)"),
                 }
                 children
             }
             _ => {
-                println!("WARNING: token stuff yeah?");
+                println!("WARNING: token stuff XD");
                 &[]
             }
         };
+        // done
         Some(Node {
             name,
             props: node_data,

kernel/src/dev/mem.rs

@@ -9,17 +9,11 @@ use crate::util::bits::Be;
 use super::fdt::FDT;
 
 impl FDT {
-    pub fn mem_range(&self) -> FDTMemRange {
-        let root = self.nodes().next().unwrap();
-        if let Some(node) = root.children().find(|n| n.name.starts_with("memory@")) {
-            if let Some(prop) = node.prop("reg") {
-                if let Some(d) = prop.data.chunks(size_of::<FDTMemRange>()).next() {
-                    let d: [u8; size_of::<FDTMemRange>()] = d.try_into().unwrap();
-                    return unsafe { transmute::<[u8; 16], FDTMemRange>(d) };
-                }
-            }
-        }
-        panic!("failed to get memory range");
+    pub fn mem_range(&self) -> Option<FDTMemRange> {
+        let reg = self.root()?.child("memory")?.prop("reg")?;
+        let data = reg.data.chunks(size_of::<FDTMemRange>()).next()?;
+        let data: [u8; size_of::<FDTMemRange>()] = data.try_into().unwrap();
+        unsafe { Some(transmute::<[u8; 16], FDTMemRange>(data)) }
     }
 }
 

kernel/src/dev/mod.rs

@@ -1,3 +1,4 @@
 pub mod fdt;
 pub mod mem;
 pub mod uart;
+pub mod pci;

kernel/src/dev/pci.rs

@@ -0,0 +1,14 @@
+use crate::println;
+
+use super::fdt::FDT;
+
+impl FDT {
+    pub fn pci_devs(&self) -> Option<()> {
+        // for dev in self.nodes() {
+        //     println!("{:#?}", dev);
+        // }
+        let node = self.root()?.child("soc")?.child("pci")?;
+        println!("{:#?}", node);
+        None
+    }
+}

kernel/src/main.rs

@@ -44,9 +44,7 @@ pub fn main(info: StartInfo) {
     unsafe {
         ALLOCATOR.init(&info.mem_range);
     }
-    for dev in info.dt.nodes() {
-        println!("{:#?}", dev);
-    }
+    info.dt.pci_devs();
 }
 
 #[panic_handler]