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KERNEL: Pre-kernel sets up the physical memory manager.

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* BUG: allocated blocks is possibly incorrect!
* prekernel no longer gets compiled as being in physical memory
This commit is contained in:
Nigel Barink
2022-09-03 01:00:17 +02:00
parent 01fcb0aa15
commit 656ca0baa8
9 changed files with 193 additions and 237 deletions
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5
source/kernel/prekernel/bootstructure.h
View File

@ -39,8 +39,3 @@ struct BootInfoBlock {
uint32_t MemorySize ;
};
const uint32_t pke = ((uint32_t)&kernel_end) - 0xC0000000;
const uint32_t BootInfoBlock_pptr = pke + 1000 - sizeof(BootInfoBlock);
const uint32_t MemoryMapHeap_pptr = pke + 0x1;

239
source/kernel/prekernel/prekernel.cpp
View File

@ -1,119 +1,140 @@
#include <stdint.h>
#include <stddef.h>
#include "multiboot.h"
#include "bootstructure.h"
#include "../memory/PhysicalMemoryManager.h"
#define CHECK_FLAG(flags, bit) ((flags) & (1 <<(bit)))
#define VADDR_TO_PADDR(vaddr) (vaddr - 0xC0000000)
#define PADDR_TO_VADDR(paddr) (paddr + 0xC0000000)
extern "C" void prekernelSetup ( unsigned long magic, multiboot_info_t* mbi) {
// Create the bootInfoBlock at its location
BootInfoBlock* BIB = (BootInfoBlock*) BootInfoBlock_pptr;
extern "C" void prekernelSetup ( unsigned long magic, multiboot_info_t* mbi)
{
/*
* Check Multiboot magic number
*/
if (magic != MULTIBOOT_BOOTLOADER_MAGIC)
{
BIB->MapIsInvalid = true;
// crash
return;
} else{
BIB->MapIsInvalid = false;
}
/* is boot device valid ? */
if (CHECK_FLAG (mbi->flags, 1))
{
BIB->bootDeviceID = mbi->boot_device;
} else{
BIB->bootDeviceID = 0x11111111;
}
/* Are mods_* valid? */
if(CHECK_FLAG ( mbi->flags, 3)){
multiboot_module_t *mod;
uint32_t i;
BIB->GrubModuleCount = mbi->mods_count;
for(i = 0, mod = (multiboot_module_t *) mbi->mods_addr; i < mbi->mods_count; i++ , mod++){
}
}
/* Is the symbol table of a.out valid? */
if (CHECK_FLAG(mbi->flags, 4))
{
BIB->ValidSymbolTable = true;
multiboot_aout_symbol_table_t *multiboot_aout_sym = &(mbi->u.aout_sym);
} else{
BIB->ValidSymbolTable = false;
}
/* Is the section header table of ELF valid? */
if (CHECK_FLAG(mbi->flags, 5))
{
BIB->ValidELFHeader = true;
multiboot_elf_section_header_table_t *multiboot_elf_sec = &(mbi->u.elf_sec);
}else{
BIB->ValidELFHeader = false;
}
/*
If we got a memory map from our bootloader we
should be parsing it to find out the memory regions available.
*/
if (CHECK_FLAG(mbi->flags, 6))
{
BIB->PhysicalMemoryMapAvailable = true;
BIB->MemoryMap = (MemoryInfoBlock*) MemoryMapHeap_pptr;
multiboot_memory_map_t *mmap = (multiboot_memory_map_t*) (mbi->mmap_addr) ;
auto MemoryMapEnd = mbi->mmap_addr + mbi->mmap_length;
auto CurrentInfoBlock = BIB->MemoryMap;
uint32_t RAM_size = 0;
while((unsigned long) mmap < MemoryMapEnd){
BIB->map_size += sizeof(MemoryInfoBlock);
CurrentInfoBlock->Base_addr = mmap->addr;
CurrentInfoBlock->Memory_Size = mmap->len;
if(mmap->type == MULTIBOOT_MEMORY_AVAILABLE)
CurrentInfoBlock->type |= 0x1;
RAM_size += mmap->len;
if(mmap->type == MULTIBOOT_MEMORY_ACPI_RECLAIMABLE)
CurrentInfoBlock->type |= 0x2;
if(mmap->type == MULTIBOOT_MEMORY_RESERVED)
CurrentInfoBlock->type |= 0x4;
if(mmap->type == MULTIBOOT_MEMORY_NVS)
CurrentInfoBlock->type |= 0x8;
if(mmap->type == MULTIBOOT_MEMORY_BADRAM)
CurrentInfoBlock->type |= 0x10;
// continue to the next block
mmap = (multiboot_memory_map_t *) ((unsigned long) mmap + mmap->size + sizeof(mmap->size));
CurrentInfoBlock->next = (MemoryInfoBlock*) CurrentInfoBlock + 16;
CurrentInfoBlock = CurrentInfoBlock->next;
/*
* Check Multiboot magic number
*/
if (magic != MULTIBOOT_BOOTLOADER_MAGIC)
{
// PANIC!!
return;
}
CurrentInfoBlock->next = (MemoryInfoBlock*) 0x0;
BIB->MemorySize = RAM_size;
} else
{
BIB->PhysicalMemoryMapAvailable = false;
}
/* Draw diagonal blue line */
if (CHECK_FLAG (mbi->flags, 12)){
BIB->EnabledVBE = true;
} else{
BIB->EnabledVBE;
}
mbi = PADDR_TO_VADDR(mbi);
// Setup the physical memory manager immmediatly
// Doing so saves the complications of doing it later when
// paging is enabled
/*
If we got a memory map from our bootloader we
should be parsing it to find out the memory regions available.
*/
if (CHECK_FLAG(mbi->flags, 6))
{
// Calculate total memory size
uint32_t RAM_size = 0;
for(
multiboot_memory_map_t* mmap = (multiboot_memory_map_t*) mbi->mmap_addr;
(unsigned long)mmap < mbi->mmap_addr + mbi->mmap_length;
mmap += mmap->size +sizeof(mmap->size)
){
RAM_size += mmap->len;
}
// Call SetupPhysicalMemoryManager at its physical address
SetupPhysicalMemoryManager ( (uint32_t)VADDR_TO_PADDR(&kernel_end), RAM_size);
for(
multiboot_memory_map_t* mmap = (multiboot_memory_map_t*) mbi->mmap_addr;
(unsigned long)mmap < mbi->mmap_addr + mbi->mmap_length;
mmap += mmap->size +sizeof(mmap->size)
){
if(mmap->type == MULTIBOOT_MEMORY_AVAILABLE)
deallocate_region(mmap->addr, mmap->len);
if(mmap->type == MULTIBOOT_MEMORY_ACPI_RECLAIMABLE)
allocate_region(mmap->addr, mmap->len);
if(mmap->type == MULTIBOOT_MEMORY_RESERVED)
allocate_region(mmap->addr, mmap->len);
if(mmap->type == MULTIBOOT_MEMORY_NVS)
allocate_region(mmap->addr, mmap->len);
if(mmap->type == MULTIBOOT_MEMORY_BADRAM)
allocate_region(mmap->addr, mmap->len);
}
// Allocate the kernel
allocate_region( (uint32_t)&kernel_begin, ( (uint32_t)&kernel_end - (uint32_t)&kernel_begin)- 0xC0000000 );
// Allocate the memory region below 1MB
allocate_region(0x0000000, 0x00100000);
}
else
{
// We didn't get a memory map from our bootloader.
// PANIC!!!!
return;
}
// allocate a full block for the other boot info!
BootInfoBlock* BIB = (BootInfoBlock*) allocate_block();
/* is boot device valid ? */
if (CHECK_FLAG (mbi->flags, 1))
{
BIB->bootDeviceID = mbi->boot_device;
} else{
BIB->bootDeviceID = 0x11111111;
}
/* Are mods_* valid? */
if(CHECK_FLAG ( mbi->flags, 3)){
multiboot_module_t *mod;
uint32_t i;
BIB->GrubModuleCount = mbi->mods_count;
for(i = 0, mod = (multiboot_module_t *) mbi->mods_addr; i < mbi->mods_count; i++ , mod++){
}
}
/* Is the symbol table of a.out valid? */
if (CHECK_FLAG(mbi->flags, 4))
{
// NOTE: Do something with it.. (Store it , process it etc...)
// printf("- Valid Symbol Table available at 0x%x.\n Tab Size: %d, str Size: %d\n", BootInfo->SymbolTableAddr, BootInfo->SymbolTabSize, BootInfo->SymbolStrSize);
BIB->ValidSymbolTable = true;
multiboot_aout_symbol_table_t *multiboot_aout_sym = &(mbi->u.aout_sym);
} else{
BIB->ValidSymbolTable = false;
}
/* Is the section header table of ELF valid? */
if (CHECK_FLAG(mbi->flags, 5))
{
// NOTE: Do something with it.. (Store it , process it etc...)
BIB->ValidELFHeader = true;
multiboot_elf_section_header_table_t *multiboot_elf_sec = &(mbi->u.elf_sec);
}else{
BIB->ValidELFHeader = false;
}
/* Draw diagonal blue line */
if (CHECK_FLAG (mbi->flags, 12)){
BIB->EnabledVBE = true;
// NOTE: Do something with it.. (Store it , process it etc...)
} else{
BIB->EnabledVBE;
}
}