mmio-rs 0.1.0

Zero-overhead, no_std memory-mapped I/O register abstraction
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146

use core::marker::PhantomData;

use crate::access::ReadWrite;
use crate::register::Register;

pub struct RegisterBlock<const N: usize> {
    base: usize,
    offsets: [usize; N],
}

impl<const N: usize> RegisterBlock<N> {
    pub const fn new(base: usize, offsets: [usize; N]) -> Self {
        Self { base, offsets }
    }

    pub fn base(&self) -> usize {
        self.base
    }

    pub fn set_base(&mut self, base: usize) {
        self.base = base;
    }

    pub fn is_valid(&self) -> bool {
        self.base != 0
    }

    pub fn reg<T: Copy>(&self, index: usize) -> Register<T, ReadWrite> {
        Register::new(self.base + self.offsets[index])
    }
}

pub struct DynamicRegisterBlock<T: Copy, Access, const N: usize> {
    base: usize,
    offsets: [usize; N],
    _phantom: PhantomData<(T, Access)>,
}

impl<T: Copy, Access, const N: usize> DynamicRegisterBlock<T, Access, N> {
    pub const fn new(base: usize, offsets: [usize; N]) -> Self {
        Self {
            base,
            offsets,
            _phantom: PhantomData,
        }
    }

    pub const fn uninit(offsets: [usize; N]) -> Self {
        Self {
            base: 0,
            offsets,
            _phantom: PhantomData,
        }
    }

    pub fn set_base_address(&mut self, base: usize) {
        self.base = base;
    }

    pub fn base_address(&self) -> usize {
        self.base
    }

    pub fn is_valid(&self) -> bool {
        self.base != 0
    }

    pub fn get(&self, index: usize) -> Register<T, Access> {
        Register::new(self.base + self.offsets[index])
    }
}

/// Define a register block with named fields and a static base address.
///
/// ```ignore
/// register_block! {
///     pub struct SysTick @ 0xE000_E010 {
///         csr: 0x00,
///         rvr: 0x04,
///         cvr: 0x08,
///     }
/// }
/// let csr = SysTick::csr();
/// ```
#[macro_export]
macro_rules! register_block {
    (
        $(#[$meta:meta])*
        $vis:vis struct $name:ident @ $base:literal {
            $( $field:ident : $offset:literal ),* $(,)?
        }
    ) => {
        $(#[$meta])*
        $vis struct $name;

        impl $name {
            $(
                #[inline(always)]
                $vis fn $field() -> $crate::Register<u32, $crate::ReadWrite> {
                    $crate::Register::new($base + $offset)
                }
            )*
        }
    };

    (
        $(#[$meta:meta])*
        $vis:vis struct $name:ident {
            $( $field:ident : $offset:literal ),* $(,)?
        }
    ) => {
        $(#[$meta])*
        $vis struct $name {
            base: usize,
        }

        impl $name {
            #[inline(always)]
            $vis const fn new(base: usize) -> Self {
                Self { base }
            }

            #[inline(always)]
            $vis const fn uninit() -> Self {
                Self { base: 0 }
            }

            #[inline(always)]
            $vis fn set_base_address(&mut self, base: usize) {
                self.base = base;
            }

            #[inline(always)]
            $vis fn is_valid(&self) -> bool {
                self.base != 0
            }

            $(
                #[inline(always)]
                $vis fn $field(&self) -> $crate::Register<u32, $crate::ReadWrite> {
                    $crate::Register::new(self.base + $offset)
                }
            )*
        }
    };
}