ax_cpu/arch/aarch64/pmu/
capability.rs

1//! Per-CPU PMUv3 capabilities, following Linux arm_pmuv3.c probe semantics.
2
3/// Architectural evidence for an event encoding.
4#[derive(Clone, Copy, Debug, Eq, PartialEq)]
5pub enum EventSupport {
6    /// The architecture reports the event as implemented.
7    Supported,
8    /// The architecture reports the event as absent.
9    Unsupported,
10    /// The encoding is outside the architectural identification bitmaps.
11    ImplementationDefined,
12}
13
14/// Immutable capabilities observed on one CPU.
15#[derive(Clone, Copy, Debug, Eq, PartialEq)]
16pub struct PmuInfo {
17    /// ID_AA64DFR0_EL1.PMUVer encoding.
18    pub version: u8,
19    /// Number of programmable counters, excluding fixed cycle/instruction counters.
20    pub num_counters: usize,
21    /// ID_AA64DFR1_EL1.PMICNTR reports a dedicated instruction counter.
22    /// This is independent of the PMUVer encoding.
23    pub has_instruction_counter: bool,
24    /// Currently configured programmable-counter overflow width.
25    pub counter_width: u8,
26    /// Currently configured cycle-counter overflow width.
27    pub cycle_counter_width: u8,
28    /// Full PMCEID0, including the extended common-event bits.
29    pub pmceid0: u64,
30    /// Full PMCEID1, including the extended common-event bits.
31    pub pmceid1: u64,
32}
33
34impl PmuInfo {
35    /// Reports PMUv3p5 long programmable-counter support.
36    pub const fn has_long_counters(self) -> bool {
37        self.version >= 6
38    }
39
40    /// Queries the common and extended common-event identification bitmaps.
41    pub const fn event_support(self, event: u16) -> EventSupport {
42        let (bitmap, bit) = match event {
43            0x0000..=0x001f => (self.pmceid0, event),
44            0x0020..=0x003f => (self.pmceid1, event - 0x20),
45            0x4000..=0x401f => (self.pmceid0, event - 0x4000 + 32),
46            0x4020..=0x403f => (self.pmceid1, event - 0x4020 + 32),
47            _ => return EventSupport::ImplementationDefined,
48        };
49        if bitmap & (1u64 << bit) != 0 {
50            EventSupport::Supported
51        } else {
52            EventSupport::Unsupported
53        }
54    }
55}
ax_cpu/arch/aarch64/pmu/capability.rs

ax_cpu/arch/aarch64/pmu/
capability.rs
