simink_macro/
lib.rs

1use proc_macro::TokenStream;
2use proc_macro2::Span;
3use quote::quote;
4use syn::{
5    parse, parse_macro_input, spanned::Spanned, Ident, ItemFn, ReturnType, Type, Visibility,
6};
7
8#[proc_macro_attribute]
9pub fn bentry(args: TokenStream, input: TokenStream) -> TokenStream {
10    let f = parse_macro_input!(input as ItemFn);
11
12    let valid_signature = f.sig.constness.is_none()
13        && f.vis == Visibility::Inherited
14        && f.sig.abi.is_none()
15        && f.sig.inputs.is_empty()
16        && f.sig.generics.params.is_empty()
17        && f.sig.generics.where_clause.is_none()
18        && f.sig.variadic.is_none()
19        && match f.sig.output {
20            ReturnType::Default => false,
21            ReturnType::Type(_, ref ty) => matches! {**ty, Type::Never(_)},
22        };
23
24    if !valid_signature {
25        return parse::Error::new(
26            f.span(),
27            "`#[entry]` function must have signature `[unsafe] fn() -> !`",
28        )
29        .to_compile_error()
30        .into();
31    }
32
33    if !args.is_empty() {
34        return parse::Error::new(Span::call_site(), "This attribute accepts no arguments")
35            .to_compile_error()
36            .into();
37    }
38
39    let tramp_ident = Ident::new(&format!("{}_trampoline", f.sig.ident), Span::call_site());
40    let ident = &f.sig.ident;
41
42    quote! {
43        global_asm!("
44    .macro enable_dbg
45    msr daifclr, #8
46    .endm
47
48    .macro mov_q, reg, val
49    .if (((\\val) >> 31) == 0 || ((\\val) >> 31) == 0x1ffffffff)
50    movz \\reg, :abs_g1_s:\\val
51    .else
52    .if (((\\val) >> 47) == 0 || ((\\val) >> 47) == 0x1ffff)
53    movz \\reg, :abs_g2_s:\\val
54    .else
55    movz \\reg, :abs_g3:\\val
56    movk \\reg, :abs_g2_nc:\\val
57    .endif
58    movk \\reg, :abs_g1_nc:\\val
59    .endif
60    movk \\reg, :abs_g0_nc:\\val
61    .endm
62
63    .macro reset_pmuserenr_el0, tmpreg
64    mrs \\tmpreg, id_aa64dfr0_el1
65    sbfx \\tmpreg, \\tmpreg, #8, #4
66    cmp \\tmpreg, #1
67    b.lt 9000f
68    msr pmuserenr_el0, xzr
699000:
70    .endm
71.pushsection \".head.text\",\"ax\"
72_head:
73    b stext
74    .long 0
75.globl stext; .align 2; stext:
76    mov x21, x0
77    bl el2_setup
78    bl __cpu_setup
79    b __primary_switch
80.type stext, @function; .size stext, .-stext
81.globl el2_setup; .align 2; el2_setup:
82
83    msr SPsel, #1
84    mrs x0, CurrentEL
85    cmp x0, #(2 << 2)
86    b.eq 1f
87    mov_q x0, (((((1) << (11))) | (((1) << (20))) | (((1) << (22))) | (((1) << (28))) | (((1) << (29)))) | 0)
88    msr sctlr_el1, x0
89    mov w0, #(0xe11)
90    isb
91    ret
92
93    1: mov_q x0, (((((1) << (4))) | (((1) << (5))) | (((1) << (11))) | (((1) << (16))) | (((1) << (18))) | (((1) << (22))) | (((1) << (23))) | (((1) << (28))) | (((1) << (29)))) | 0)
94    msr sctlr_el2, x0
95
96    mov_q x0, (((((1) << (11))) | (((1) << (20))) | (((1) << (22))) | (((1) << (28))) | (((1) << (29)))) | 0)
97    msr sctlr_el1, x0
98
99
100    mov x0, #(0x00000040 | 0x00000080 | 0x00000100 | 0x00000200 | 0x00000005)
101
102    msr spsr_el2, x0
103    msr elr_el2, lr
104    mov w0, #(0xe12)
105    eret
106.type el2_setup, @function; .size el2_setup, .-el2_setup
107.globl __cpu_setup; .align 2; __cpu_setup:
108
109    tlbi vmalle1
110    dsb nsh
111
112    mov x0, #3 << 20
113    msr cpacr_el1, x0
114    mov x0, #1 << 12
115    msr mdscr_el1, x0
116    isb
117    enable_dbg
118    reset_pmuserenr_el0 x0
119
120    ldr x5, =((0x00) << ((0) * 8)) | ((0x04) << ((1) * 8)) | ((0x0c) << ((2) * 8)) | ((0x44) << ((3) * 8)) | ((0xff) << ((4) * 8)) | ((0xbb) << ((5) * 8))
121    msr mair_el1, x5
122    ret
123.type __cpu_setup, @function; .size __cpu_setup, .-__cpu_setup
124__primary_switch:
125    adrp x4, __top_stack
126    mov x1, x4
127    mov sp, x1
128    bl clear_bss
129    b main
130.type __primary_switch, @function; .size __primary_switch, .-__primary_switch
131.popsection");
132
133        #[doc(hidden)]
134        #[export_name = "main"]
135        pub unsafe extern "C" fn #tramp_ident() {
136            #ident()
137        }
138
139        #f
140    }
141    .into()
142}
simink_macro/lib.rs

simink_macro/
lib.rs
