1 | //! Control register |
2 | |
3 | /// Control register |
4 | #[derive (Clone, Copy, Debug)] |
5 | pub struct Control { |
6 | bits: u32, |
7 | } |
8 | |
9 | impl Control { |
10 | /// Creates a `Control` value from raw bits. |
11 | #[inline ] |
12 | pub fn from_bits(bits: u32) -> Self { |
13 | Self { bits } |
14 | } |
15 | |
16 | /// Returns the contents of the register as raw bits |
17 | #[inline ] |
18 | pub fn bits(self) -> u32 { |
19 | self.bits |
20 | } |
21 | |
22 | /// Thread mode privilege level |
23 | #[inline ] |
24 | pub fn npriv(self) -> Npriv { |
25 | if self.bits & (1 << 0) == (1 << 0) { |
26 | Npriv::Unprivileged |
27 | } else { |
28 | Npriv::Privileged |
29 | } |
30 | } |
31 | |
32 | /// Sets the thread mode privilege level value (nPRIV). |
33 | #[inline ] |
34 | pub fn set_npriv(&mut self, npriv: Npriv) { |
35 | let mask = 1 << 0; |
36 | match npriv { |
37 | Npriv::Unprivileged => self.bits |= mask, |
38 | Npriv::Privileged => self.bits &= !mask, |
39 | } |
40 | } |
41 | |
42 | /// Currently active stack pointer |
43 | #[inline ] |
44 | pub fn spsel(self) -> Spsel { |
45 | if self.bits & (1 << 1) == (1 << 1) { |
46 | Spsel::Psp |
47 | } else { |
48 | Spsel::Msp |
49 | } |
50 | } |
51 | |
52 | /// Sets the SPSEL value. |
53 | #[inline ] |
54 | pub fn set_spsel(&mut self, spsel: Spsel) { |
55 | let mask = 1 << 1; |
56 | match spsel { |
57 | Spsel::Psp => self.bits |= mask, |
58 | Spsel::Msp => self.bits &= !mask, |
59 | } |
60 | } |
61 | |
62 | /// Whether context floating-point is currently active |
63 | #[inline ] |
64 | pub fn fpca(self) -> Fpca { |
65 | if self.bits & (1 << 2) == (1 << 2) { |
66 | Fpca::Active |
67 | } else { |
68 | Fpca::NotActive |
69 | } |
70 | } |
71 | |
72 | /// Sets the FPCA value. |
73 | #[inline ] |
74 | pub fn set_fpca(&mut self, fpca: Fpca) { |
75 | let mask = 1 << 2; |
76 | match fpca { |
77 | Fpca::Active => self.bits |= mask, |
78 | Fpca::NotActive => self.bits &= !mask, |
79 | } |
80 | } |
81 | } |
82 | |
83 | /// Thread mode privilege level |
84 | #[derive (Clone, Copy, Debug, Eq, PartialEq)] |
85 | pub enum Npriv { |
86 | /// Privileged |
87 | Privileged, |
88 | /// Unprivileged |
89 | Unprivileged, |
90 | } |
91 | |
92 | impl Npriv { |
93 | /// Is in privileged thread mode? |
94 | #[inline ] |
95 | pub fn is_privileged(self) -> bool { |
96 | self == Npriv::Privileged |
97 | } |
98 | |
99 | /// Is in unprivileged thread mode? |
100 | #[inline ] |
101 | pub fn is_unprivileged(self) -> bool { |
102 | self == Npriv::Unprivileged |
103 | } |
104 | } |
105 | |
106 | /// Currently active stack pointer |
107 | #[derive (Clone, Copy, Debug, Eq, PartialEq)] |
108 | pub enum Spsel { |
109 | /// MSP is the current stack pointer |
110 | Msp, |
111 | /// PSP is the current stack pointer |
112 | Psp, |
113 | } |
114 | |
115 | impl Spsel { |
116 | /// Is MSP the current stack pointer? |
117 | #[inline ] |
118 | pub fn is_msp(self) -> bool { |
119 | self == Spsel::Msp |
120 | } |
121 | |
122 | /// Is PSP the current stack pointer? |
123 | #[inline ] |
124 | pub fn is_psp(self) -> bool { |
125 | self == Spsel::Psp |
126 | } |
127 | } |
128 | |
129 | /// Whether context floating-point is currently active |
130 | #[derive (Clone, Copy, Debug, Eq, PartialEq)] |
131 | pub enum Fpca { |
132 | /// Floating-point context active. |
133 | Active, |
134 | /// No floating-point context active |
135 | NotActive, |
136 | } |
137 | |
138 | impl Fpca { |
139 | /// Is a floating-point context active? |
140 | #[inline ] |
141 | pub fn is_active(self) -> bool { |
142 | self == Fpca::Active |
143 | } |
144 | |
145 | /// Is a floating-point context not active? |
146 | #[inline ] |
147 | pub fn is_not_active(self) -> bool { |
148 | self == Fpca::NotActive |
149 | } |
150 | } |
151 | |
152 | /// Reads the CPU register |
153 | #[inline ] |
154 | pub fn read() -> Control { |
155 | let bits: u32 = call_asm!(__control_r() -> u32); |
156 | Control { bits } |
157 | } |
158 | |
159 | /// Writes to the CPU register. |
160 | #[inline ] |
161 | pub unsafe fn write(control: Control) { |
162 | let control: u32 = control.bits(); |
163 | call_asm!(__control_w(control: u32)); |
164 | } |
165 | |