diff options
| -rw-r--r-- | cortex-m-rt/Cargo.toml | 5 | ||||
| -rw-r--r-- | cortex-m-rt/build.rs | 16 | ||||
| -rw-r--r-- | cortex-m-rt/src/lib.rs | 18 |
3 files changed, 31 insertions, 8 deletions
diff --git a/cortex-m-rt/Cargo.toml b/cortex-m-rt/Cargo.toml index fc1c181..e04bdc1 100644 --- a/cortex-m-rt/Cargo.toml +++ b/cortex-m-rt/Cargo.toml @@ -13,14 +13,13 @@ version = "0.3.0" r0 = "0.2.1" [dependencies.cortex-m] -optional = true version = "0.2.7" [features] default = ["exceptions", "linker-script"] # service all exceptions using the default handler -exceptions = ["cortex-m"] +exceptions = [] # generic linker script linker-script = [] # provides a panic_fmt implementation that calls the abort instruction (`udf 0xfe`) -abort-on-panic = []
\ No newline at end of file +abort-on-panic = [] diff --git a/cortex-m-rt/build.rs b/cortex-m-rt/build.rs index c52b434..45642c5 100644 --- a/cortex-m-rt/build.rs +++ b/cortex-m-rt/build.rs @@ -1,3 +1,5 @@ +use std::env; + #[cfg(feature = "linker-script")] mod imp { use std::env; @@ -6,6 +8,8 @@ mod imp { use std::path::PathBuf; pub fn main() { + ::has_fpu(); + // Put the linker script somewhere the linker can find it let out = &PathBuf::from(env::var_os("OUT_DIR").unwrap()); File::create(out.join("link.x")) @@ -21,7 +25,17 @@ mod imp { #[cfg(not(feature = "linker-script"))] mod imp { - pub fn main() {} + pub fn main() { + ::has_fpu(); + } +} + +fn has_fpu() { + let target = env::var("TARGET").unwrap(); + + if target.ends_with("eabihf") { + println!("cargo:rustc-cfg=has_fpu"); + } } fn main() { diff --git a/cortex-m-rt/src/lib.rs b/cortex-m-rt/src/lib.rs index 4e10b59..4a7ce44 100644 --- a/cortex-m-rt/src/lib.rs +++ b/cortex-m-rt/src/lib.rs @@ -155,7 +155,6 @@ #![feature(used)] #![no_std] -#[cfg(feature = "exceptions")] extern crate cortex_m; extern crate compiler_builtins; extern crate r0; @@ -189,6 +188,18 @@ unsafe extern "C" fn reset_handler() -> ! { r0::zero_bss(&mut _sbss, &mut _ebss); r0::init_data(&mut _sdata, &mut _edata, &_sidata); + match () { + #[cfg(has_fpu)] + () => { + // NOTE(safe) no exception / interrupt that also accesses the FPU + // can occur here + let scb = &*cortex_m::peripheral::SCB.get(); + scb.enable_fpu(); + } + #[cfg(not(has_fpu))] + () => {} + } + // Neither `argc` or `argv` make sense in bare metal context so we just // stub them main(0, ::core::ptr::null()); @@ -210,6 +221,5 @@ static RESET_HANDLER: unsafe extern "C" fn() -> ! = reset_handler; #[cfg(feature = "exceptions")] #[link_section = ".rodata.exceptions"] #[used] -static EXCEPTIONS: exception::Handlers = exception::Handlers { - ..exception::DEFAULT_HANDLERS -}; +static EXCEPTIONS: exception::Handlers = + exception::Handlers { ..exception::DEFAULT_HANDLERS }; |