From 49bf92a7aaf10a4777ea512303e442588f4ce2e5 Mon Sep 17 00:00:00 2001
From: Nathan Ringo <nathan@remexre.com>
Date: Sun, 15 Sep 2024 03:25:30 -0500
Subject: Start of serious allocator work.

---
 crates/kernel/src/arch/riscv64/mod.rs | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

(limited to 'crates/kernel/src/arch/riscv64/mod.rs')

diff --git a/crates/kernel/src/arch/riscv64/mod.rs b/crates/kernel/src/arch/riscv64/mod.rs
index 011e244..48718c2 100644
--- a/crates/kernel/src/arch/riscv64/mod.rs
+++ b/crates/kernel/src/arch/riscv64/mod.rs
@@ -1,9 +1,22 @@
+use crate::cpu_locals::CPULocals;
+use core::{arch::asm, ptr::NonNull};
+
 pub mod interrupts;
 pub mod paging;
 
+/// Returns a pointer to the per-CPU locals.
+pub fn get_cpu_locals() -> NonNull<CPULocals> {
+    // SAFETY: The entrypoint sets this up, and safe code cannot invalidate it.
+    unsafe {
+        let tp;
+        asm!("mv {out}, tp", out = out(reg) tp);
+        NonNull::new_unchecked(tp)
+    }
+}
+
 /// Halts the hart.
 pub fn sleep_forever() -> ! {
     loop {
-        unsafe { core::arch::asm!("wfi") }
+        unsafe { asm!("wfi") }
     }
 }
-- 
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