luxos/Kernel/library/memory/memory_init.c

/*
 * memory-init.c
 *
 *  Created on: Aug 27, 2011
 *      Author: Tiberiu
 */
#include <memory-add.h>
#include <multiboot.h>
#include <debugio.h>
#include "../../drivers/cmos/cmos.h"
#include <stdio.h>

uint32 mem_kernel_end = 0;
uint8 mem_initialized = 0;

uint32 _memory_get_total_mem(MultibootInfo* info)
{
	// Grub was nice enough to give us info
	if (info->Flags & MultibootInfo_MEMORY) return (1024 + info->MemoryUpper);

	// No? Get info from CMOS
	uint8 low, high;
	uint32 total;

	low = CmosRead(0x30);
	high = CmosRead(0x31);
	total = (uint32)(low | high<<8) + 1024;

	Error("Mem", "%#Missing memory info from bootloader. Reading from CMOS: %ukb\n", ColorLightRed, total);

	return total;
}

void _memory_reserve_system(MultibootInfo* info)
{
	MagicBreakpoint();
	if ((info->Flags & MultibootInfo_MEM_MAP) != 0)
	{
		MultibootMemoryMapEntry* location = (MultibootMemoryMapEntry*)info->MemoryMapAddress;

		while ((uint32)location < (info->MemoryMapAddress + info->MemoryMapLength))
		{
			if (location->Type > 1)
				MemPhReserveBlocks((uint32)location->Address, (uint32)location->Length);

			location = (MultibootMemoryMapEntry*) ((uint32)location + location->Size + sizeof(uint32));
		}
	}

	else
	{
		Error("Mem", "%#Missing %#memory map%# info from bootloader.\n", ColorLightRed, ColorWhite, ColorLightRed);

		// Standard memory hole at 15mb
		MemPhReserveBlocks(0x00F00000, 0x00100000);
	}

}


void MemoryInitialize (MultibootInfo* info)
{
	// Get total system memory
	uint32 totalSystemMemory = _memory_get_total_mem(info);

	// Initialize physical & virtual memory managers
	uint32 end = mem_kernel_end + 0x80000;
	MemPhInitialize(totalSystemMemory);
	PagingInitialize(&end);

	// Reserve physical blocks
	_memory_reserve_system(info);

	uint32 i;
	// Allocate some space for the kernel heap
	for (i = KERNEL_HEAP_START; i <= KERNEL_HEAP_END; i += 0x1000)
		PagingMapPage(MemPhAllocateBlock(), i, PageWriteable, KernelDirectory);

	// Create the kernel heap
	KernelHeap = MemHeapCreate(KERNEL_HEAP_START, KERNEL_HEAP_START
			+ KERNEL_HEAP_INITIAL_SIZE, 0xCFFFF000, 3);	// is kernel, writeable

	Log("Mem", "Done initializing memory!\n");
	
	mem_initialized = 2;
}

void MemoryTempInitialize (uint32 kernel_end)
{
	mem_initialized = 1;
	mem_kernel_end = kernel_end;
	Log("Mem", "Initialized temporary memory manager, allocating from %#0x%x.\n", ColorWhite, mem_kernel_end);
}