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#include <shim.h>
#include <lib.h>
#include <stdint.h>
#include <panic.h>
#include "mboot.h"
#define MBOOT_HEADER_MAGIC 0x36D76289
#define MBOOT_CMDLINE 1
#define MBOOT_MEMORY_MAP 6
#define MBOOT_ELF_SYMBOLS 9
#define MBOOT_OLD_RSDP 14
#define MBOOT_NEW_RSDP 15
struct mboot_info {
uint32_t total_size;
uint32_t reserved;
char tags[];
};
struct mboot_tag {
uint32_t type;
uint32_t size;
char data[];
};
struct mboot_tag_elf_sections {
uint32_t type;
uint32_t size;
uint16_t num;
uint16_t entsize;
uint16_t shndx;
uint16_t reserved;
char sections[];
};
struct mboot_tag_elf_sections_entry {
uint32_t sh_name;
uint32_t sh_type;
uint64_t sh_flags;
uint64_t sh_addr;
uint64_t sh_offset;
uint64_t sh_size;
uint32_t sh_link;
uint32_t sh_info;
uint64_t sh_addralign;
uint64_t sh_entsize;
};
struct mboot_mmap_entry {
uint64_t addr;
uint64_t len;
uint32_t type;
uint32_t zero;
};
struct mboot_tag_mmap {
uint32_t type;
uint32_t size;
uint32_t entry_size;
uint32_t entry_version;
struct mboot_mmap_entry entries[];
};
struct mboot_tag_old_rsdp {
uint32_t type;
uint32_t size;
uint8_t rsdp[];
};
struct mboot_tag_new_rsdp {
uint32_t type;
uint32_t size;
uint8_t rsdp[];
};
struct mboot_tag_cmdline {
uint32_t type;
uint32_t size;
uint8_t cmdline[];
};
static void read_symbols(
struct boot_info *shim_info,
struct mboot_tag_elf_sections *sections
) {
shim_info->symbol_table = sections->sections;
// struct mboot_elf_section_header *section =
// (struct mboot_elf_section_header *) (layout->elf_section_headers);
//
// for (uint32_t i = 0; i < layout->num; i++) {
// char buf[20];
//
// ultoa(i, buf, 10);
// serial_out_str("[");
// serial_out_str(buf);
// serial_out_str("]\t");
//
// serial_out_str((char *)(kaddr(symtab) + section->sh_name));
// serial_out('\t');
//
// ultoa(section->sh_type, buf, 16);
// serial_out_str("type: 0x");
// serial_out_str(buf);
// serial_out('\t');
//
// ultoa(section->sh_addr, buf, 16);
// serial_out_str("addr: 0x");
// serial_out_str(buf);
// serial_out('\t');
//
// ultoa(section->sh_offset, buf, 16);
// serial_out_str("offset: 0x");
// serial_out_str(buf);
// serial_out('\n');
//
// section++;
// }
}
static void read_cmdline(
struct boot_info *shim_info,
struct mboot_tag_cmdline *cmdline
) {
uint32_t size = cmdline->size - 8;
if (size >= CMDLINE_MAX)
size = CMDLINE_MAX; // truncate :(
memcpy(shim_info->cmdline, cmdline->cmdline, size);
shim_info->cmdline[size] = '\0';
}
static const char *segment_type[] = {
"Reserved",
"Free",
"Reserved",
"ACPI Reserved",
"Hibernation",
"Defective",
"Unknown"
};
static void read_memory_map(
struct boot_info *shim_info,
struct mboot_tag_mmap *map
) {
int idx = 0;
uintptr_t i = (uintptr_t)map->entries;
kprintf("MEMORY MAP\n");
char buf[20];
for ( ;
i < (uintptr_t)map->entries + map->size;
i += map->entry_size, idx++
) {
struct mboot_mmap_entry *seg = (struct mboot_mmap_entry *) i;
const char *type = NULL;
if (seg->type > 4)
type = segment_type[6];
else
type = segment_type[seg->type];
kprintf("ADDR: 0x%16p LEN: %4s TYPE: %s (%d)\n",
(void *)seg->addr,
btoa(seg->len, buf),
type,
seg->type
);
if (seg->type != 1 || seg->len < 1)
continue;
shim_info->map.entries[idx].addr = seg->addr;
shim_info->map.entries[idx].len = seg->len;
}
shim_info->map.entry_count = idx;
}
static void read_old_rsdp(
struct boot_info *shim_info,
struct mboot_tag_old_rsdp *rsdp
) {
if (shim_info->acpi_table != NULL)
return; // xsdp is newer and has been loaded
shim_info->acpi_table = rsdp->rsdp;
}
static void read_new_rsdp(
struct boot_info *shim_info,
struct mboot_tag_new_rsdp *rsdp
) {
shim_info->acpi_table = rsdp->rsdp;
}
void mboot_load_info(
long mboot_magic,
const void *mboot_data_ptr,
struct boot_info *shim_info
) {
if (mboot_magic != MBOOT_HEADER_MAGIC)
panic("invalid multiboot magic");
memset(shim_info, 0, sizeof(struct boot_info));
struct mboot_info *mboot_info = (struct mboot_info *) mboot_data_ptr;
const char *mboot_end = ((char *) mboot_info) + mboot_info->total_size;
char *tag_ptr = mboot_info->tags;
while (tag_ptr < mboot_end) {
struct mboot_tag *tag = (struct mboot_tag *) tag_ptr;
switch (tag->type) {
case MBOOT_CMDLINE:
read_cmdline(
shim_info,
(struct mboot_tag_cmdline *) tag
);
break;
case MBOOT_MEMORY_MAP:
read_memory_map(
shim_info,
(struct mboot_tag_mmap *) tag
);
break;
case MBOOT_ELF_SYMBOLS:
read_symbols(
shim_info,
(struct mboot_tag_elf_sections *) tag
);
break;
case MBOOT_OLD_RSDP:
read_old_rsdp(
shim_info,
(struct mboot_tag_old_rsdp *) tag
);
break;
case MBOOT_NEW_RSDP:
read_new_rsdp(
shim_info,
(struct mboot_tag_new_rsdp *) tag
);
break;
default:
break;
}
int size = tag->size;
if (size % 8 != 0) {
size += 8 - (size % 8);
}
tag_ptr += size;
}
}
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