can now print device tree

kernel/src/arch/riscv64/paging.rs

@@ -0,0 +1,34 @@
+// stolen from https://osblog.stephenmarz.com/index.html chapter 3 which I'm prolly gonna start
+// following for now bc don't wanna learn x86_64 :)
+
+use crate::{
+    arch::csr::{self, satp}, fdt::print_fdt, println
+};
+
+use super::asm::linker_static;
+
+linker_static!(HEAP_START: usize, ".dword _heap_start");
+static HEAP_SIZE: usize = 128 * 1024 * 1024;
+
+pub struct Entry(u64);
+
+pub struct Table {
+    pub entries: [Entry; 2usize.pow(9)],
+}
+
+pub fn init(fdt: usize) {
+    unsafe {
+        println!("heap start: 0x{:x}", HEAP_START);
+        print_fdt(fdt);
+        let table_start = HEAP_START as *mut Table;
+        csr::satp::write(satp::Satp {
+            mode: satp::Mode::Sv39,
+            asid: 0,
+            ppn: table_start,
+        });
+        let satp = csr::satp::read();
+        println!("satp: {satp:?}");
+        let x = *(0x9000_0000 as *mut u8);
+        println!("we got {x}");
+    }
+}