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264 changes: 264 additions & 0 deletions coresimd/arm/cmsis.rs
Original file line number Diff line number Diff line change
@@ -0,0 +1,264 @@
#![allow(non_snake_case)]
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Could you add a top-level comment here linking to the document / documents that specifies these intrinsics?


/// Extracted from [CMSIS 5]'s CMSIS/Core/Include/cmsis_gcc.h
///
/// [CMSIS 5]: https://github.com/ARM-software/CMSIS_5
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Should this be //! instead?

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I would also prefer this to be a top-module documentation string (using //!).


/* Core function access */

/// Enable IRQ Interrupts
///
/// Enables IRQ interrupts by clearing the I-bit in the CPSR. Can only be
/// executed in Privileged modes.
#[inline(always)]
pub unsafe fn __enable_irq() {
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These should use the assert_instr macro.

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@gnzlbg gnzlbg Jul 7, 2018

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@alexcrichton these are all in a module guarded by cfg(target_feature = "mclass"), so they don't technically need #[target_feature(enable = "mclass")], but I think we still do always use target_feature(enable) everywhere else in the library, including these cases.

I think I would prefer to have it here as well just in case we end up moving functions around internally in the future.


@japaric is it possible to detect cmsis at run-time? Or is it something that must always be configured statically at compile-time?

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Yeah I think it's probably prudent to go ahead and add the attribute to manually enable it just in case.

asm!("cpsie i" : : : "memory" : "volatile");
}

/// Disable IRQ Interrupts
///
/// Disables IRQ interrupts by setting the I-bit in the CPSR. Can only be
/// executed in Privileged modes.
#[inline(always)]
pub unsafe fn __disable_irq() {
asm!("cpsid i" : : : "memory" : "volatile");
}

/// Get Control Register
///
/// Returns the content of the Control Register.
#[inline(always)]
pub unsafe fn __get_CONTROL() -> u32 {
let result: u32;
asm!("mrs $0, CONTROL" : "=r"(result) : : : "volatile");
result
}

/// Set Control Register
///
/// Writes the given value to the Control Register.
#[inline(always)]
pub unsafe fn __set_CONTROL(control: u32) {
asm!("msr CONTROL, $0" : : "r"(control) : "memory" : "volatile");
}

/// Get IPSR Register
///
/// Returns the content of the IPSR Register.
#[inline(always)]
pub unsafe fn __get_IPSR() -> u32 {
let result: u32;
asm!("mrs $0, IPSR" : "=r"(result) : : : "volatile");
result
}

/// Get APSR Register
///
/// Returns the content of the APSR Register.
#[inline(always)]
pub unsafe fn __get_APSR() -> u32 {
let result: u32;
asm!("mrs $0, APSR" : "=r"(result) : : : "volatile");
result
}

/// Get xPSR Register
///
/// Returns the content of the xPSR Register.
#[inline(always)]
pub unsafe fn __get_xPSR() -> u32 {
let result: u32;
asm!("mrs $0, XPSR" : "=r"(result) : : : "volatile");
result
}

/// Get Process Stack Pointer
///
/// Returns the current value of the Process Stack Pointer (PSP).
#[inline(always)]
pub unsafe fn __get_PSP() -> u32 {
let result: u32;
asm!("mrs $0, PSP" : "=r"(result) : : : "volatile");
result
}

/// Set Process Stack Pointer
///
/// Assigns the given value to the Process Stack Pointer (PSP).
#[inline(always)]
pub unsafe fn __set_PSP(top_of_proc_stack: u32) {
asm!("msr PSP, $0" : : "r"(top_of_proc_stack) : : "volatile");
}

/// Get Main Stack Pointer
///
/// Returns the current value of the Main Stack Pointer (MSP).
#[inline(always)]
pub unsafe fn __get_MSP() -> u32 {
let result: u32;
asm!("mrs $0, MSP" : "=r"(result) : : : "volatile");
result
}

/// Set Main Stack Pointer
///
/// Assigns the given value to the Main Stack Pointer (MSP).
#[inline(always)]
pub unsafe fn __set_MSP(top_of_main_stack: u32) {
asm!("msr MSP, $0" : : "r"(top_of_main_stack) : : "volatile");
}

/// Get Priority Mask
///
/// Returns the current state of the priority mask bit from the Priority Mask
/// Register.
#[inline(always)]
pub unsafe fn __get_PRIMASK() -> u32 {
let result: u32;
asm!("mrs $0, PRIMASK" : "=r"(result) : : "memory" : "volatile");
result
}

/// Set Priority Mask
///
/// Assigns the given value to the Priority Mask Register.
#[inline(always)]
pub unsafe fn __set_PRIMASK(pri_mask: u32) {
asm!("msr PRIMASK, $0" : : "r"(pri_mask) : : "volatile");
}

#[cfg(target_feature = "v7")]
mod v7 {
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I think it would make it more clear to move this to its own file. We have a different v7 module in the arm submodule already, maybe one needs to refactor things a bit.

/// Enable FIQ
///
/// Enables FIQ interrupts by clearing the F-bit in the CPSR. Can only be
/// executed in Privileged modes.
#[inline(always)]
pub unsafe fn __enable_fault_irq() {
asm!("cpsie f" : : : "memory" : "volatile");
}

/// Disable FIQ
///
/// Disables FIQ interrupts by setting the F-bit in the CPSR. Can only be
/// executed in Privileged modes.
#[inline(always)]
pub unsafe fn __disable_fault_irq() {
asm!("cpsid f" : : : "memory" : "volatile");
}

/// Get Base Priority
///
/// Returns the current value of the Base Priority register.
#[inline(always)]
pub unsafe fn __get_BASEPRI() -> u32 {
let result: u32;
asm!("mrs $0, BASEPRI" : "=r"(result) : : : "volatile");
result
}

/// Set Base Priority
///
/// Assigns the given value to the Base Priority register.
#[inline(always)]
pub unsafe fn __set_BASEPRI(base_pri: u32) {
asm!("msr BASEPRI, $0" : : "r"(base_pri) : "memory" : "volatile");
}

/// Set Base Priority with condition
///
/// Assigns the given value to the Base Priority register only if BASEPRI
/// masking is disabled, or the new value increases the BASEPRI
/// priority level.
#[inline(always)]
pub unsafe fn __set_BASEPRI_MAX(base_pri: u32) {
asm!("msr BASEPRI_MAX, $0" : : "r"(base_pri) : "memory" : "volatile");
}

/// Get Fault Mask
///
/// Returns the current value of the Fault Mask register.
#[inline(always)]
pub unsafe fn __get_FAULTMASK() -> u32 {
let result: u32;
asm!("mrs $0, FAULTMASK" : "=r"(result) : : : "volatile");
result
}

/// Set Fault Mask
///
/// Assigns the given value to the Fault Mask register.
#[inline(always)]
pub unsafe fn __set_FAULTMASK(fault_mask: u32) {
asm!("msr FAULTMASK, $0" : : "r"(fault_mask) : "memory" : "volatile");
}
}

#[cfg(target_feature = "v7")]
pub use self::v7::*;

/* Core instruction access */

/// No Operation
///
/// No Operation does nothing. This instruction can be used for code alignment
/// purposes.
#[inline(always)]
pub unsafe fn __NOP() {
asm!("nop" : : : : "volatile");
}

/// Wait For Interrupt
///
/// Wait For Interrupt is a hint instruction that suspends execution until one
/// of a number of events occurs.
#[inline(always)]
pub unsafe fn __WFI() {
asm!("wfi" : : : : "volatile");
}

/// Wait For Event
///
/// Wait For Event is a hint instruction that permits the processor to enter a
/// low-power state until one of a number of events occurs.
#[inline(always)]
pub unsafe fn __WFE() {
asm!("wfe" : : : : "volatile");
}

/// Send Event
///
/// Send Event is a hint instruction. It causes an event to be signaled to the
/// CPU.
#[inline(always)]
pub unsafe fn __SEV() {
asm!("sev" : : : : "volatile");
}

/// Instruction Synchronization Barrier
///
/// Instruction Synchronization Barrier flushes the pipeline in the processor,
/// so that all instructions following the ISB are fetched from cache or
/// memory, after the instruction has been completed.
#[inline(always)]
pub unsafe fn __ISB() {
asm!("isb 0xF" : : : "memory" : "volatile");
}

/// Data Synchronization Barrier
///
/// Acts as a special kind of Data Memory Barrier. It completes when all
/// explicit memory accesses before this instruction complete.
#[inline(always)]
pub unsafe fn __DSB() {
asm!("dsb 0xF" : : : "memory" : "volatile");
}

/// Data Memory Barrier
///
/// Ensures the apparent order of the explicit memory operations before and
/// after the instruction, without ensuring their completion.
#[inline(always)]
pub unsafe fn __DMB() {
asm!("dmb 0xF" : : : "memory" : "volatile");
}
5 changes: 5 additions & 0 deletions coresimd/arm/mod.rs
Original file line number Diff line number Diff line change
Expand Up @@ -9,6 +9,11 @@
//! [arm_dat]: https://developer.arm.com/technologies/neon/intrinsics
#![allow(non_camel_case_types)]

#[cfg(target_feature = "mclass")]
mod cmsis;
#[cfg(target_feature = "mclass")]
pub use self::cmsis::*;

mod v6;
pub use self::v6::*;

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