Chroma/inc/kernel/boot/boot.h

155 lines
4.9 KiB
C

#pragma once
/************************
*** Team Kitty, 2020 ***
*** Chroma ***
***********************/
#include <stdint.h>
/*
;* Memory map
;* 0h - 600h reserved for the system
* V----------- CAN REMOVE -----------V
;* 600h - 800h stage1 (MBR/VBR, boot.bin)
;* 800h - 6C00h stage2 (this)
* ∧----------- CAN REMOVE -----------∧
;* 6C00h - 7C00h stack (7000h - 700Fh SMP trampoline code)
;* 8000h - 9000h bootboot structure
;* 9000h - A000h environment
* V----------- CAN REMOVE -----------V
;* A000h - B000h disk buffer / PML4
;* B000h - C000h PDPE, higher half core 4K slots
;* C000h - D000h PDE 4K
;* D000h - E000h PTE 4K
;* E000h - F000h PDPE, 4G physical RAM identity mapped 2M
;* F000h - 10000h PDE 2M
;* 10000h - 11000h PDE 2M
;* 11000h - 12000h PDE 2M
;* 12000h - 13000h PDE 2M
;* 13000h - 14000h PTE 4K
* ∧----------- CAN REMOVE -----------∧
;* 14000h - 9F000h core stacks (1k per core)
;*
;* At first big enough free hole, initrd. Usually at 1Mbyte.
*/
/* ELF headers hate me.
* Let's do this the hard way. */
#define ELF_IDENT_MAGIC_OFF 0x0
#define ELF_IDENT_CLASS_OFF 0x4
#define ELF_IDENT_DATA_OFF 0x5
#define ELF_IDENT_VERSION_OFF 0x6
#define ELF_IDENT_OSABI_OFF 0x7
#define ELF_IDENT_ABI_VERSION_OFF 0x8
#define ELF_IDENT_PAD_OFF 0x9
#define ELFTYPE_OFF 0x10
#define ELFMACHINE_OFF 0x12
#define ELFVERSION_OFF 0x14
#define ELFENTRY_OFF 0x18
#define ELFPHOFF_OFF 0x20
#define ELFSHOFF_OFF 0x28
#define ELFFLAGS_OFF 0x30
#define ELFEHSIZE_OFF 0x34
#define ELFPHENTSIZE_OFF 0x36
#define ELFPHNUM_OFF 0x38
#define ELFSHENTSIZE_OFF 0x3A
#define ELFSHNUM_OFF 0x3C
#define ELFSHSTRNDX_OFF 0x40
#define BOOT_MAGIC "BOOT"
/* minimum protocol level:
* hardcoded kernel name, static kernel memory addresses
* this is the default */
#define PROTOCOL_MINIMAL 0
/* static protocol level:
* kernel name parsed from environment, static kernel memory addresses */
#define PROTOCOL_STATIC 1
/* dynamic protocol level:
* kernel name parsed, kernel memory addresses from ELF or PE symbols */
#define PROTOCOL_DYNAMIC 2
/* big-endian flag */
#define PROTOCOL_BIGENDIAN 0x80
/* loader types, just informational */
#define LOADER_BIOS (0<<2)
/* unless we get to a weird stage, these should never be used. */
#define LOADER_UEFI (1<<2)
#define LOADER_RPI (2<<2)
/* framebuffer pixel format, only 32 bits supported */
#define FB_ARGB 0
#define FB_RGBA 1
#define FB_ABGR 2
#define FB_BGRA 3
/* mmap entry, type is stored in least significant tetrad (half byte) of size
* this means size described in 16 byte units (not a problem, most modern
* firmware report memory in pages, 4096 byte units anyway). */
typedef struct {
uint64_t ptr;
uint64_t size;
} __attribute__((packed)) MMapEnt;
#define MMapEnt_Ptr(a) (a->ptr)
#define MMapEnt_Size(a) (a->size & 0xFFFFFFFFFFFFFFF0)
#define MMapEnt_Type(a) (a->size & 0xF)
#define MMapEnt_IsFree(a) ((a->size&0xF)==1)
#define MMAP_USED 0 /* don't use. Reserved or unknown regions */
#define MMAP_FREE 1 /* usable memory */
#define MMAP_ACPI 2 /* acpi memory, volatile and non-volatile as well */
#define MMAP_MMIO 3 /* memory mapped IO region */
#define INITRD_MAXSIZE 16 /* Mb */
typedef struct {
/* first 64 bytes is platform independent */
uint8_t magic[4]; /* 'BOOT' magic */
uint32_t size; /* length of bootboot structure, minimum 128 */
uint8_t protocol; /* 1, static addresses, see PROTOCOL_* and LOADER_* above */
uint8_t fb_type; /* framebuffer type, see FB_* above */
uint16_t numcores; /* number of processor cores */
uint16_t bspid; /* Bootstrap processor ID (Local APIC Id on x86_64) */
int16_t timezone; /* in minutes -1440..1440 */
uint8_t datetime[8]; /* in BCD yyyymmddhhiiss UTC (independent to timezone) */
uint64_t initrd_ptr; /* ramdisk image position and size */
uint64_t initrd_size;
uint8_t *fb_ptr; /* framebuffer pointer and dimensions */
uint32_t fb_size;
uint32_t fb_width;
uint32_t fb_height;
uint32_t fb_scanline;
/* the rest (64 bytes) is platform specific */
union {
struct {
uint64_t acpi_ptr;
uint64_t smbi_ptr;
uint64_t efi_ptr;
uint64_t mp_ptr;
uint64_t unused0;
uint64_t unused1;
uint64_t unused2;
uint64_t unused3;
} x86_64;
struct {
uint64_t acpi_ptr;
uint64_t mmio_ptr;
uint64_t efi_ptr;
uint64_t unused0;
uint64_t unused1;
uint64_t unused2;
uint64_t unused3;
uint64_t unused4;
} aarch64;
} arch;
/* from 128th byte, MMapEnt[], more records may follow */
MMapEnt mmap;
/* use like this:
* MMapEnt *mmap_ent = &bootboot.mmap; mmap_ent++;
* until you reach bootboot->size */
} __attribute__((packed)) bootinfo;