Kernel: Multiboot data and kernel command lines are now global variables

This commit is contained in:
Bananymous 2023-01-10 17:50:24 +02:00
parent 1a65ea977d
commit c6467b8ebc
8 changed files with 117 additions and 24 deletions

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@ -90,13 +90,13 @@ namespace VESA
bool Initialize() bool Initialize()
{ {
if (!(s_multiboot_info->flags & MULTIBOOT_FLAGS_FRAMEBUFFER)) if (!(g_multiboot_info->flags & MULTIBOOT_FLAGS_FRAMEBUFFER))
{ {
derrorln("bootloader did not provide a memory map"); derrorln("bootloader did not provide a memory map");
return false; return false;
} }
auto& framebuffer = s_multiboot_info->framebuffer; auto& framebuffer = g_multiboot_info->framebuffer;
s_addr = framebuffer.addr; s_addr = framebuffer.addr;
s_bpp = framebuffer.bpp; s_bpp = framebuffer.bpp;
s_pitch = framebuffer.pitch; s_pitch = framebuffer.pitch;

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@ -7,7 +7,7 @@
.set MB_CHECKSUM, -(MB_MAGIC + MB_FLAGS) #checksum of above, to prove we are multiboot .set MB_CHECKSUM, -(MB_MAGIC + MB_FLAGS) #checksum of above, to prove we are multiboot
# Multiboot header # Multiboot header
.section .multiboot .section .multiboot, "aw"
.align 4 .align 4
.long MB_MAGIC .long MB_MAGIC
.long MB_FLAGS .long MB_FLAGS
@ -19,28 +19,111 @@
.long 600 .long 600
.long 32 .long 32
# Create stack .section .bss, "aw", @nobits
.section .bss # Create stack
stack_bottom: stack_bottom:
.skip 16384 # 16 KiB .skip 16384
stack_top: stack_top:
.global g_kernel_cmdline
g_kernel_cmdline:
.skip 4096
# Reserve memory for paging structures,
# we will identity map first 4 MiB
# 0 MiB -> 2 MiB: kernel
# 2 MiB -> 3 MiB: kmalloc
# 3 MiB -> 4 Mib: kmalloc_eternal
.align 32
boot_page_directory_pointer_table:
.skip 4 * 8
.align 4096
boot_page_directory1:
.skip 512 * 8
.section .text, "a"
.global g_multiboot_info
g_multiboot_info:
.skip 4
.global g_multiboot_magic
g_multiboot_magic:
.skip 4
has_cpuid:
pushfl
pushfl
xorl $0x00200000, (%esp)
popfl
pushfl
popl %eax
xorl (%esp), %eax
popfl
andl $0x00200000, %eax
ret
has_pae:
call has_cpuid
cmpl $0, %eax
jz .exit
movl $0, %eax
cpuid
movl %edx, %eax
andl $0x40, %eax # PAE is bit 6 in edx
.exit:
ret
.section .text
.global _start .global _start
.type _start, @function .type _start, @function
_start: _start:
# Initialize stack and multiboot info
movl $stack_top, %esp movl $stack_top, %esp
movl %eax, g_multiboot_magic
movl %ebx, g_multiboot_info
pushl %eax
pushl %ebx
# Copy kernel command line to known location
movl %ebx, %esi
addl $16, %esi
movl (%esi), %esi
movl $1024, %ecx
movl $g_kernel_cmdline, %edi
rep movsl
call has_pae
cmpl $0, %eax
jz system_halt
# identity map first 4 MiB
movl $(0x00000000 + 0x83), boot_page_directory1 + 0
movl $(0x00200000 + 0x83), boot_page_directory1 + 8
movl $(boot_page_directory1 + 0x01), boot_page_directory_pointer_table
# enable PAE
movl %cr4, %ecx
orl $0x20, %ecx
movl %ecx, %cr4
# set address of paging structures
movl $boot_page_directory_pointer_table, %ecx
movl %ecx, %cr3
# enable paging
movl %cr0, %ecx
orl $0x80000000, %ecx
movl %ecx, %cr0
xchgw %bx, %bx
# call global constuctors
call _init call _init
# call to the kernel itself
call kernel_main call kernel_main
system_halt:
cli cli
1: 1: hlt
hlt
jmp 1b jmp 1b
.size _start, . - _start

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@ -1,9 +1,9 @@
ENTRY(_start) ENTRY (_start)
SECTIONS SECTIONS
{ {
. = 1M; . = 0x00100000;
.text BLOCK(4K) : ALIGN(4K) .text BLOCK(4K) : ALIGN(4K)
{ {
*(.multiboot) *(.multiboot)
@ -22,4 +22,6 @@ SECTIONS
*(COMMON) *(COMMON)
*(.bss) *(.bss)
} }
}
g_kernel_end = .;
}

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@ -9,5 +9,6 @@ $(ARCHDIR)/boot.o \
$(ARCHDIR)/CPUID.o \ $(ARCHDIR)/CPUID.o \
$(ARCHDIR)/GDT.o \ $(ARCHDIR)/GDT.o \
$(ARCHDIR)/IDT.o \ $(ARCHDIR)/IDT.o \
$(ARCHDIR)/MMU.o \
$(ARCHDIR)/Paging.o \ $(ARCHDIR)/Paging.o \
$(ARCHDIR)/VESA.o \ $(ARCHDIR)/VESA.o \

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@ -48,4 +48,5 @@ struct multiboot_info_t
framebuffer_info_t framebuffer; framebuffer_info_t framebuffer;
} __attribute__((packed)); } __attribute__((packed));
extern multiboot_info_t* s_multiboot_info; extern "C" multiboot_info_t* g_multiboot_info;
extern "C" uint32_t g_multiboot_magic;

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@ -1,3 +1,4 @@
#include <BAN/Memory.h>
#include <kernel/kmalloc.h> #include <kernel/kmalloc.h>
#include <kernel/Panic.h> #include <kernel/Panic.h>
#include <kernel/Serial.h> #include <kernel/Serial.h>

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@ -4,6 +4,7 @@
#include <kernel/Input.h> #include <kernel/Input.h>
#include <kernel/kmalloc.h> #include <kernel/kmalloc.h>
#include <kernel/kprint.h> #include <kernel/kprint.h>
#include <kernel/MMU.h>
#include <kernel/multiboot.h> #include <kernel/multiboot.h>
#include <kernel/Paging.h> #include <kernel/Paging.h>
#include <kernel/PIC.h> #include <kernel/PIC.h>
@ -17,8 +18,7 @@
#define DISABLE_INTERRUPTS() asm volatile("cli") #define DISABLE_INTERRUPTS() asm volatile("cli")
#define ENABLE_INTERRUPTS() asm volatile("sti") #define ENABLE_INTERRUPTS() asm volatile("sti")
extern "C" const char g_kernel_cmdline[];
multiboot_info_t* s_multiboot_info;
using namespace BAN; using namespace BAN;

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@ -9,6 +9,8 @@
#define ALIGN (alignof(max_align_t)) #define ALIGN (alignof(max_align_t))
extern "C" uintptr_t g_kernel_end;
/* /*
#### KMALLOC ################ #### KMALLOC ################
*/ */
@ -47,14 +49,17 @@ static bool s_initialized = false;
void kmalloc_initialize() void kmalloc_initialize()
{ {
if (!(s_multiboot_info->flags & (1 << 6))) if (!(g_multiboot_info->flags & (1 << 6)))
Kernel::Panic("Kmalloc: Bootloader didn't provide a memory map"); Kernel::Panic("Kmalloc: Bootloader didn't provide a memory map");
if (g_kernel_end > s_kmalloc_node_base)
Kernel::Panic("Kmalloc: Kernel end is over kmalloc base");
// Validate kmalloc memory // Validate kmalloc memory
bool valid = false; bool valid = false;
for (size_t i = 0; i < s_multiboot_info->mmap_length;) for (size_t i = 0; i < g_multiboot_info->mmap_length;)
{ {
multiboot_memory_map_t* mmmt = (multiboot_memory_map_t*)(s_multiboot_info->mmap_addr + i); multiboot_memory_map_t* mmmt = (multiboot_memory_map_t*)(g_multiboot_info->mmap_addr + i);
if (mmmt->type == 1) if (mmmt->type == 1)
{ {