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
|
// limine scans the loaded image for these magic numbers, baserevision is
// a handshake, essentially we ask limine for rev 3, and if it supports it,
// limine zeros it out
pub const BaseRevision = extern struct {
magic0: u64 = 0xf9562b2d5c95a6c8,
magic1: u64 = 0x6a7b384944536bdc,
revision: u64,
pub fn init(revision: u64) BaseRevision {
return .{ .revision = revision };
}
};
// bracketing markers, they are pretty optional but when we add proper
// limine requests, having these here comes handy
pub const RequestsStartMarker = extern struct {
m0: u64 = 0xf6b8f4b39de7d1ae,
m1: u64 = 0xfab91a6940fcb9cf,
m2: u64 = 0x785c6ed015d3e316,
m3: u64 = 0x181e920a7852b9d9,
};
pub const RequestsEndMarker = extern struct {
m0: u64 = 0xadc0e0531bb10d03,
m1: u64 = 0x9572709f31764c62,
};
// every request id starts with this common magic, then two request specific
// words, bootloader scans .limine_requests for these and fills in `response`
fn requestId(a: u64, b: u64) [4]u64 {
return .{ 0xc7b1dd30df4c8b88, 0x0a82e883a194f07b, a, b };
}
// this comes from the limine spec
// you can see it in the header files
pub const Framebuffer = extern struct {
address: [*]u8,
width: u64,
height: u64,
pitch: u64, // bytes per row (not always width*bpp/8)
bpp: u16, // bits per pixel
memory_model: u8, // 1 = rgb
red_mask_size: u8,
red_mask_shift: u8,
green_mask_size: u8,
green_mask_shift: u8,
blue_mask_size: u8,
blue_mask_shift: u8,
// 7 bytes of padding land here (extern struct alignment before edid_size)
edid_size: u64,
edid: ?*anyopaque,
// response revision 1 and up, unused for now:
mode_count: u64,
modes: ?*anyopaque,
};
pub const FramebufferResponse = extern struct {
revision: u64,
framebuffer_count: u64,
framebuffers: ?[*]*Framebuffer,
};
pub const FramebufferRequest = extern struct {
id: [4]u64 = requestId(0x9d5827dcd881dd75, 0xa3148604f6fab11b),
revision: u64 = 0,
response: ?*FramebufferResponse = null,
};
// ask limine for a bigger bootstrap stack than its ~64 kib default cause
// revos vm init builds a large struct on the stack and runs a fat recursive
// descent parser to register its stdlib, which page faults the machine
pub const StackSizeResponse = extern struct {
revision: u64,
};
pub const StackSizeRequest = extern struct {
id: [4]u64 = requestId(0x224ef0460a8e8926, 0xe1cb0fc25f46ea3d),
revision: u64 = 0,
response: ?*StackSizeResponse = null,
stack_size: u64,
};
// hhdm = higher half direct map, limine linearly maps all of physical memory
// starting at `offset`, so any physical address p is reachable at p + offset
// this is how we touch physical frames without setting up our own page tables
// and this is how my hypothetical future girlfriend should touch my pointer
pub const HhdmResponse = extern struct {
revision: u64,
offset: u64,
};
pub const HhdmRequest = extern struct {
id: [4]u64 = requestId(0x48dcf1cb8ad2b852, 0x63984e959a98244b),
revision: u64 = 0,
response: ?*HhdmResponse = null,
};
// what each region of physical memory is
// only `usable` (0) is ours to hand out freely
// the rest belongs to firmware and other stingy shits
pub const MemoryType = enum(u64) {
usable = 0,
reserved = 1,
acpi_reclaimable = 2,
acpi_nvs = 3,
bad = 4,
bootloader_reclaimable = 5,
kernel_and_modules = 6,
framebuffer = 7,
_,
};
pub const MemoryMapEntry = extern struct {
base: u64,
length: u64,
type: MemoryType,
};
// note: `entries` is an array of pointers to entries, not the entries inline
// note: i will forget this
pub const MemoryMapResponse = extern struct {
revision: u64,
entry_count: u64,
entries: ?[*]*MemoryMapEntry,
};
pub const MemoryMapRequest = extern struct {
id: [4]u64 = requestId(0x67cf3d9d378a806f, 0xe304acdfc50c3c62),
revision: u64 = 0,
response: ?*MemoryMapResponse = null,
};
|
