kernel/arch/riscv64/instruction/
sbi.rs

1use core::arch::asm;
2
3pub enum Extension {
4    Base = 0x10,
5    SetTimer = 0x00,
6    ConsolePutChar = 0x01,
7    ConsoleGetChar = 0x02,
8    Timer = 0x54494d45,
9    Ipi = 0x735049,
10    Rfence = 0x52464e43,
11    Hsm = 0x48534d,
12    Srst = 0x53525354,
13    Pmu = 0x504d55,
14}
15
16pub struct SbiRet {
17    pub error: usize,
18    pub value: usize,
19}
20
21pub enum SbiError {
22    Failed = -1,
23    NotSupported = -2,
24    InvalidParam = -3,
25    Denied = -4,
26    InvalidAddress = -5,
27    AlreadyAvailable = -6,
28    AlreadyStarted = -7,
29    AlreadyStopped = -8,
30}
31
32impl SbiError {
33    pub fn from_error(error: usize) -> SbiError {
34        let error = error as isize;
35        match error {
36            -1 => SbiError::Failed,
37            -2 => SbiError::NotSupported,
38            -3 => SbiError::InvalidParam,
39            -4 => SbiError::Denied,
40            -5 => SbiError::InvalidAddress,
41            -6 => SbiError::AlreadyAvailable,
42            -7 => SbiError::AlreadyStarted,
43            -8 => SbiError::AlreadyStopped,
44            _ => panic!("Invalid SBI error code"),
45        }
46    }
47}
48
49pub fn sbi_call(extension: Extension, function: usize, arg0: usize, arg1: usize) -> Result<usize, SbiError> {
50    let error: usize;
51    let ret: usize;
52
53    unsafe {
54        asm!(
55            "ecall",
56            inout("a0") arg0 => error,
57            inout("a1") arg1 => ret,
58            in("a2") 0,
59            in("a3") 0,
60            in("a4") 0,
61            in("a5") 0,
62            in("a6") function,
63            in("a7") extension as usize,
64            options(nostack),
65        );
66    }
67
68    match error {
69        0 => Ok(ret),
70        _ => Err(SbiError::from_error(error)),
71    }
72}
73
74pub fn sbi_console_putchar(c: char) {
75    let _ = sbi_call(Extension::ConsolePutChar, 0, c as usize, 0);
76}
77
78pub fn sbi_console_getchar() -> char {
79    let ret = sbi_call(Extension::ConsoleGetChar, 0, 0, 0);
80    match ret {
81        Ok(c) => c as u8 as char,
82        Err(_) => '\0',
83    }
84}
85
86pub fn sbi_set_timer(stime_value: u64) {
87    let _ = sbi_call(Extension::Timer, 0, stime_value as usize, 0);
88}
89
90pub fn sbi_system_reset(reset_type: u32, reset_reason: u32) -> ! {
91    let _ = sbi_call(Extension::Srst, 0, reset_type as usize, reset_reason as usize);
92    loop {}
93}
kernel/arch/riscv64/instruction/sbi.rs

kernel/arch/riscv64/instruction/
sbi.rs
