sbi_spec/
hsm.rs

1//! Chapter 9. Hart State Management Extension (EID #0x48534D "HSM").
2
3/// Extension ID for Hart State Management extension.
4pub const EID_HSM: usize = crate::eid_from_str("HSM") as _;
5pub use fid::*;
6
7/// Hart states.
8///
9/// Declared in Table 1 at §9.
10pub mod hart_state {
11    /// The hart is physically powered-up and executing normally.
12    pub const STARTED: usize = 0;
13    /// The hart is not executing in supervisor-mode or any lower privilege mode.
14    ///
15    /// It is probably powered-down by the SBI implementation if the underlying platform
16    /// has a mechanism to physically power-down harts.
17    pub const STOPPED: usize = 1;
18    /// The hart is pending before being started
19    ///
20    /// Some other hart has requested to start (or power-up) the hart from the STOPPED state,
21    /// and the SBI implementation is still working to get the hart in the STARTED state.
22    pub const START_PENDING: usize = 2;
23    /// The hart is pending before being stopped.
24    ///
25    /// The hart has requested to stop (or power-down) itself from the STARTED state,
26    /// and the SBI implementation is still working to get the hart in the STOPPED state.
27    pub const STOP_PENDING: usize = 3;
28    /// The hart is in a platform-specific suspend (or low-power) state.
29    pub const SUSPENDED: usize = 4;
30    /// The hart is pending before being suspended.
31    ///
32    /// The hart has requested to put itself in a platform-specific low-power state
33    /// from the STARTED state, and the SBI implementation is still working to get
34    /// the hart in the platform-specific SUSPENDED state.
35    pub const SUSPEND_PENDING: usize = 5;
36    /// The hart is pending before being resumed.
37    ///
38    /// An interrupt or platform specific hardware event has caused the hart to resume
39    /// normal execution from the SUSPENDED state, and the SBI implementation is still
40    /// working to get the hart in the STARTED state.
41    pub const RESUME_PENDING: usize = 6;
42}
43
44/// Hart suspend types.
45pub mod suspend_type {
46    /// Default retentive hart suspend type.
47    pub const RETENTIVE: u32 = 0;
48    /// Default non-retentive hart suspend type.
49    pub const NON_RETENTIVE: u32 = 0x8000_0000;
50}
51
52/// Declared in §9.5.
53mod fid {
54    /// Function ID to start executing the given hart at specified address in supervisor-mode.
55    ///
56    /// Declared in §9.1.
57    pub const HART_START: usize = 0;
58    /// Function ID to stop executing the calling hart in supervisor-mode.
59    ///
60    /// Declared in §9.2.
61    pub const HART_STOP: usize = 1;
62    /// Function ID to get the current status (or HSM state id) of the given hart.
63    ///
64    /// Declared in §9.3.
65    pub const HART_GET_STATUS: usize = 2;
66    /// Function ID to put the calling hart into suspend or platform-specific lower power states.
67    ///
68    /// Declared in §9.4.
69    pub const HART_SUSPEND: usize = 3;
70}
sbi_spec/hsm.rs

sbi_spec/
hsm.rs
