remove asm feature

The `asm!()` macro was stabilized in
rust-lang/rust#91728. This removes the feature
and imports it through `core::arch` instead.

Author: bradjc

arch/cortex-m/src/lib.rs

@@ -2,10 +2,11 @@
 
 #![crate_name = "cortexm"]
 #![crate_type = "rlib"]
-#![feature(asm, asm_sym)]
+#![feature(asm_sym)]
 #![feature(naked_functions)]
 #![no_std]
 
+use core::arch::asm;
 use core::fmt::Write;
 
 pub mod mpu;

arch/cortex-m/src/scb.rs

@@ -2,6 +2,8 @@
 //!
 //! <http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.dui0553a/CIHFDJCA.html>
 
+use core::arch::asm;
+
 use kernel::utilities::registers::interfaces::{ReadWriteable, Readable, Writeable};
 use kernel::utilities::registers::{register_bitfields, register_structs, ReadOnly, ReadWrite};
 use kernel::utilities::StaticRef;

arch/cortex-m/src/support.rs

@@ -1,3 +1,4 @@
+use core::arch::asm;
 use core::ops::FnOnce;
 
 #[cfg(all(target_arch = "arm", target_os = "none"))]

arch/cortex-m0/src/lib.rs

@@ -2,7 +2,7 @@
 
 #![crate_name = "cortexm0"]
 #![crate_type = "rlib"]
-#![feature(asm, asm_sym, naked_functions)]
+#![feature(asm_sym, naked_functions)]
 #![no_std]
 
 // Re-export the base generic cortex-m functions here as they are
@@ -13,6 +13,8 @@ pub use cortexm::nvic;
 pub use cortexm::print_cortexm_state as print_cortexm0_state;
 pub use cortexm::syscall;
 
+use core::arch::asm;
+
 extern "C" {
     // _estack is not really a function, but it makes the types work
     // You should never actually invoke it!!

arch/cortex-m0p/src/lib.rs

@@ -2,7 +2,6 @@
 
 #![crate_name = "cortexm0p"]
 #![crate_type = "rlib"]
-#![feature(asm)]
 #![feature(naked_functions)]
 #![no_std]
 
@@ -26,6 +25,8 @@ pub use cortexm0::generic_isr;
 pub use cortexm0::hard_fault_handler;
 pub use cortexm0::systick_handler;
 
+use core::arch::asm;
+
 // Mock implementation for tests on Travis-CI.
 #[cfg(not(any(target_arch = "arm", target_os = "none")))]
 pub unsafe extern "C" fn switch_to_user(

arch/rv32i/src/lib.rs

@@ -2,9 +2,10 @@
 
 #![crate_name = "rv32i"]
 #![crate_type = "rlib"]
-#![feature(asm, asm_sym, const_fn_trait_bound, naked_functions)]
+#![feature(asm_sym, const_fn_trait_bound, naked_functions)]
 #![no_std]
 
+use core::arch::asm;
 use core::fmt::Write;
 
 use kernel::utilities::registers::interfaces::{Readable, Writeable};

arch/rv32i/src/support.rs

@@ -1,6 +1,7 @@
 //! Core low-level operations.
 
 use crate::csr::{mstatus::mstatus, CSR};
+use core::arch::asm;
 use core::ops::FnOnce;
 
 #[cfg(all(target_arch = "riscv32", target_os = "none"))]

arch/rv32i/src/syscall.rs

@@ -1,5 +1,6 @@
 //! Kernel-userland system call interface for RISC-V architecture.
 
+use core::arch::asm;
 use core::convert::TryInto;
 use core::fmt::Write;
 use core::mem::size_of;

boards/nano_rp2040_connect/src/main.rs

@@ -7,7 +7,9 @@
 // https://github.com/rust-lang/rust/issues/62184.
 #![cfg_attr(not(doc), no_main)]
 #![deny(missing_docs)]
-#![feature(asm, naked_functions)]
+#![feature(naked_functions)]
+
+use core::arch::asm;
 
 use capsules::virtual_alarm::VirtualMuxAlarm;
 use components::gpio::GpioComponent;

boards/pico_explorer_base/src/main.rs

@@ -7,7 +7,9 @@
 // https://github.com/rust-lang/rust/issues/62184.
 #![cfg_attr(not(doc), no_main)]
 #![deny(missing_docs)]
-#![feature(asm, naked_functions)]
+#![feature(naked_functions)]
+
+use core::arch::asm;
 
 use kernel::dynamic_deferred_call::{DynamicDeferredCall, DynamicDeferredCallClientState};