WIP owned irqs

embassy-macros/src/lib.rs

@@ -98,3 +98,65 @@ pub fn task(args: TokenStream, item: TokenStream) -> TokenStream {
     };
     result.into()
 }
+
+#[proc_macro]
+pub fn interrupt_declare(item: TokenStream) -> TokenStream {
+    let name = syn::parse_macro_input!(item as syn::Ident);
+    let name = format_ident!("{}", name);
+    let name_interrupt = format_ident!("{}Interrupt", name);
+    let name_handler = format!("__EMBASSY_{}_HANDLER", name);
+
+    let result = quote! {
+        #[allow(non_camel_case_types)]
+        pub struct #name_interrupt(());
+        unsafe impl OwnedInterrupt for #name_interrupt {
+            type Priority = Priority;
+            fn number(&self) -> u8 {
+                Interrupt::#name as u8
+            }
+            unsafe fn __handler(&self) -> &'static ::core::sync::atomic::AtomicPtr<u32> {
+                #[export_name = #name_handler]
+                static HANDLER: ::core::sync::atomic::AtomicPtr<u32> = ::core::sync::atomic::AtomicPtr::new(::core::ptr::null_mut());
+                &HANDLER
+            }
+        }
+    };
+    result.into()
+}
+
+#[proc_macro]
+pub fn interrupt_take(item: TokenStream) -> TokenStream {
+    let name = syn::parse_macro_input!(item as syn::Ident);
+    let name = format!("{}", name);
+    let name_interrupt = format_ident!("{}Interrupt", name);
+    let name_handler = format!("__EMBASSY_{}_HANDLER", name);
+
+    let result = quote! {
+        {
+            #[allow(non_snake_case)]
+            #[export_name = #name]
+            pub unsafe extern "C" fn trampoline() {
+                extern "C" {
+                    #[link_name = #name_handler]
+                    static HANDLER: ::core::sync::atomic::AtomicPtr<u32>;
+                }
+
+                let p = HANDLER.load(::core::sync::atomic::Ordering::Acquire);
+                if !p.is_null() {
+                    let f: fn() = ::core::mem::transmute(p);
+                    f()
+                }
+            }
+
+            static TAKEN: ::core::sync::atomic::AtomicBool = ::core::sync::atomic::AtomicBool::new(false);
+
+            if TAKEN.compare_and_swap(false, true, ::core::sync::atomic::Ordering::AcqRel) {
+                panic!("IRQ Already taken");
+            }
+
+            let irq: interrupt::#name_interrupt = unsafe { ::core::mem::transmute(()) };
+            irq
+        }
+    };
+    result.into()
+}