//! Data Watchpoint and Trace unit
#[cfg(not(armv6m))]
use volatile_register::WO;
use volatile_register::{RO, RW};
use crate::peripheral::DWT;
/// Register block
#[repr(C)]
pub struct RegisterBlock {
/// Control
pub ctrl: RW<u32>,
/// Cycle Count
#[cfg(not(armv6m))]
pub cyccnt: RW<u32>,
/// CPI Count
#[cfg(not(armv6m))]
pub cpicnt: RW<u32>,
/// Exception Overhead Count
#[cfg(not(armv6m))]
pub exccnt: RW<u32>,
/// Sleep Count
#[cfg(not(armv6m))]
pub sleepcnt: RW<u32>,
/// LSU Count
#[cfg(not(armv6m))]
pub lsucnt: RW<u32>,
/// Folded-instruction Count
#[cfg(not(armv6m))]
pub foldcnt: RW<u32>,
/// Cortex-M0(+) does not have these parts
#[cfg(armv6m)]
reserved: [u32; 6],
/// Program Counter Sample
pub pcsr: RO<u32>,
/// Comparators
#[cfg(armv6m)]
pub c: [Comparator; 2],
#[cfg(not(armv6m))]
/// Comparators
pub c: [Comparator; 16],
#[cfg(not(armv6m))]
reserved: [u32; 932],
/// Lock Access
#[cfg(not(armv6m))]
pub lar: WO<u32>,
/// Lock Status
#[cfg(not(armv6m))]
pub lsr: RO<u32>,
}
/// Comparator
#[repr(C)]
pub struct Comparator {
/// Comparator
pub comp: RW<u32>,
/// Comparator Mask
pub mask: RW<u32>,
/// Comparator Function
pub function: RW<u32>,
reserved: u32,
}
// DWT CTRL register fields
const NUMCOMP_OFFSET: u32 = 28;
const NOTRCPKT: u32 = 1 << 27;
const NOEXTTRIG: u32 = 1 << 26;
const NOCYCCNT: u32 = 1 << 25;
const NOPRFCNT: u32 = 1 << 24;
const CYCCNTENA: u32 = 1 << 0;
impl DWT {
/// Number of comparators implemented
///
/// A value of zero indicates no comparator support.
#[inline]
pub fn num_comp() -> u8 {
// NOTE(unsafe) atomic read with no side effects
unsafe { ((*Self::PTR).ctrl.read() >> NUMCOMP_OFFSET) as u8 }
}
/// Returns `true` if the the implementation supports sampling and exception tracing
#[cfg(not(armv6m))]
#[inline]
pub fn has_exception_trace() -> bool {
// NOTE(unsafe) atomic read with no side effects
unsafe { (*Self::PTR).ctrl.read() & NOTRCPKT == 0 }
}
/// Returns `true` if the implementation includes external match signals
#[cfg(not(armv6m))]
#[inline]
pub fn has_external_match() -> bool {
// NOTE(unsafe) atomic read with no side effects
unsafe { (*Self::PTR).ctrl.read() & NOEXTTRIG == 0 }
}
/// Returns `true` if the implementation supports a cycle counter
#[cfg(not(armv6m))]
#[inline]
pub fn has_cycle_counter() -> bool {
// NOTE(unsafe) atomic read with no side effects
unsafe { (*Self::PTR).ctrl.read() & NOCYCCNT == 0 }
}
/// Returns `true` if the implementation the profiling counters
#[cfg(not(armv6m))]
#[inline]
pub fn has_profiling_counter() -> bool {
// NOTE(unsafe) atomic read with no side effects
unsafe { (*Self::PTR).ctrl.read() & NOPRFCNT == 0 }
}
/// Enables the cycle counter
///
/// The global trace enable ([`DCB::enable_trace`]) should be set before
/// enabling the cycle counter, the processor may ignore writes to the
/// cycle counter enable if the global trace is disabled
/// (implementation defined behaviour).
///
/// [`DCB::enable_trace`]: crate::peripheral::DCB::enable_trace
#[cfg(not(armv6m))]
#[inline]
pub fn enable_cycle_counter(&mut self) {
unsafe { self.ctrl.modify(|r| r | CYCCNTENA) }
}
/// Disables the cycle counter
#[cfg(not(armv6m))]
#[inline]
pub fn disable_cycle_counter(&mut self) {
unsafe { self.ctrl.modify(|r| r & !CYCCNTENA) }
}
/// Returns `true` if the cycle counter is enabled
#[cfg(not(armv6m))]
#[inline]
pub fn cycle_counter_enabled() -> bool {
// NOTE(unsafe) atomic read with no side effects
unsafe { (*Self::PTR).ctrl.read() & CYCCNTENA != 0 }
}
/// Returns the current clock cycle count
#[cfg(not(armv6m))]
#[inline]
#[deprecated(
since = "0.7.4",
note = "Use `cycle_count` which follows the C-GETTER convention"
)]
pub fn get_cycle_count() -> u32 {
Self::cycle_count()
}
/// Returns the current clock cycle count
#[cfg(not(armv6m))]
#[inline]
pub fn cycle_count() -> u32 {
// NOTE(unsafe) atomic read with no side effects
unsafe { (*Self::PTR).cyccnt.read() }
}
/// Set the cycle count
#[cfg(not(armv6m))]
#[inline]
pub fn set_cycle_count(&mut self, count: u32) {
unsafe { self.cyccnt.write(count) }
}
/// Removes the software lock on the DWT
///
/// Some devices, like the STM32F7, software lock the DWT after a power cycle.
#[cfg(not(armv6m))]
#[inline]
pub fn unlock() {
// NOTE(unsafe) atomic write to a stateless, write-only register
unsafe { (*Self::PTR).lar.write(0xC5AC_CE55) }
}
/// Get the CPI count
///
/// Counts additional cycles required to execute multi-cycle instructions,
/// except those recorded by [`lsu_count`], and counts any instruction fetch
/// stalls.
///
/// [`lsu_count`]: DWT::lsu_count
#[cfg(not(armv6m))]
#[inline]
pub fn cpi_count() -> u8 {
// NOTE(unsafe) atomic read with no side effects
unsafe { (*Self::PTR).cpicnt.read() as u8 }
}
/// Set the CPI count
#[cfg(not(armv6m))]
#[inline]
pub fn set_cpi_count(&mut self, count: u8) {
unsafe { self.cpicnt.write(count as u32) }
}
/// Get the total cycles spent in exception processing
#[cfg(not(armv6m))]
#[inline]
pub fn exception_count() -> u8 {
// NOTE(unsafe) atomic read with no side effects
unsafe { (*Self::PTR).exccnt.read() as u8 }
}
/// Set the exception count
#[cfg(not(armv6m))]
#[inline]
pub fn set_exception_count(&mut self, count: u8) {
unsafe { self.exccnt.write(count as u32) }
}
/// Get the total number of cycles that the processor is sleeping
///
/// ARM recommends that this counter counts all cycles when the processor is sleeping,
/// regardless of whether a WFI or WFE instruction, or the sleep-on-exit functionality,
/// caused the entry to sleep mode.
/// However, all sleep features are implementation defined and therefore when
/// this counter counts is implementation defined.
#[cfg(not(armv6m))]
#[inline]
pub fn sleep_count() -> u8 {
// NOTE(unsafe) atomic read with no side effects
unsafe { (*Self::PTR).sleepcnt.read() as u8 }
}
/// Set the sleep count
#[cfg(not(armv6m))]
#[inline]
pub fn set_sleep_count(&mut self, count: u8) {
unsafe { self.sleepcnt.write(count as u32) }
}
/// Get the additional cycles required to execute all load or store instructions
#[cfg(not(armv6m))]
#[inline]
pub fn lsu_count() -> u8 {
// NOTE(unsafe) atomic read with no side effects
unsafe { (*Self::PTR).lsucnt.read() as u8 }
}
/// Set the lsu count
#[cfg(not(armv6m))]
#[inline]
pub fn set_lsu_count(&mut self, count: u8) {
unsafe { self.lsucnt.write(count as u32) }
}
/// Get the folded instruction count
///
/// Increments on each instruction that takes 0 cycles.
#[cfg(not(armv6m))]
#[inline]
pub fn fold_count() -> u8 {
// NOTE(unsafe) atomic read with no side effects
unsafe { (*Self::PTR).foldcnt.read() as u8 }
}
/// Set the folded instruction count
#[cfg(not(armv6m))]
#[inline]
pub fn set_fold_count(&mut self, count: u8) {
unsafe { self.foldcnt.write(count as u32) }
}
}