BarinkOS/src/kernel/kernel.cpp
Nigel fb2a19e11d FAT16 structures read from disk using ATA.
The proper reading of folders and files is not yet implemented. Although
it is close.
2021-12-24 21:31:10 +01:00

136 lines
4.4 KiB
C++

#include "kernel.h"
#define GB4 524288
#define GB2 262144
extern "C" void kernel_main (void);
extern "C" void early_main(unsigned long magic, unsigned long addr){
/** initialize terminal interface */
kterm_init();
if (magic != MULTIBOOT_BOOTLOADER_MAGIC){
printf("Invalid magic number: 0x%x\n", magic);
return;
}
CheckMBT( (multiboot_info_t *) addr);
multiboot_info_t* mbt = (multiboot_info_t*) addr;
/* Are mmap_* valid? */
if (CHECK_FLAG(mbt->flags, 6)){
PhysicalMemoryManager_initialise( mbt->mmap_addr, GB2/* Seriously dangerous hardcoded memory value*/);
PhysicalMemoryManager_initialise_available_regions(mbt->mmap_addr, mbt->mmap_addr + mbt->mmap_length);
PhysicalMemoryManager_deinitialise_kernel();
extern uint8_t* kernel_begin;
extern uint8_t* kernel_end;
printf("Kernel MemoryMap:\n");
printf("kernel: 0x%x - 0x%x\n", &kernel_begin , &kernel_end);
}
initGDT();
kernel_main();
}
extern "C" void kernel_main (void) {
printf("call to init serial\n");
init_serial();
print_serial("Serial port initialized!");
RSDPTR* rsd = FindRSD();
RSDT* rsd_table = getRSDT(rsd);
// Enumerate the PCI bus
PCI_Enumerate();
TestIDEController();
int devNumber = 0 ;
for ( auto device : ide_devices){
if (!device.Reserved)
continue;
printf("Device %d\n" , devNumber);
printf (" Device on Channel: (0x%x) %s\n" ,device.Channel, device.Channel == 0 ? "Primary" : "Secondary");
printf (" Device drive:(0x%x) %s\n" , device.Drive, device.Drive? "Slave" : "Master");
printf (" Device Type:(0x%x) %s\n" , device.Type, device.Type ? "ATAPI" : "ATA");
devNumber ++;
}
enum BUS_PORT {
Primary= 0x1f0,
Secondary = 0x170
};
ATA_DEVICE::Identify((uint16_t) BUS_PORT::Primary, DEVICE_DRIVE::MASTER);
const int C = 0;
const int H = 0;
const int HPC = 16;
const int SPT = 63;
int S = 1;
uint32_t LBA = (C*HPC+H) * SPT + (S-1);
printf("LBA: %d\n" , LBA);
uint16_t buffer [256];
ATA_DEVICE::Read(BUS_PORT::Primary, DEVICE_DRIVE::MASTER, LBA, buffer);
MBR* mbr = (MBR*) buffer;
printf("BootSector: 0x%x\n", mbr->ValidBootsector );
for( int i = 0 ; i < 4 ; i ++){
PartitionTableEntry PT = mbr->TableEntries[i];
printf("Partition %d [ %d sectors, PartitionType: %x, 0x%x, \nLBA Start: 0x%x ]\n" ,
i, PT.Number_sectors_inPartition, PT.PartitionType, mbr->uniqueID, PT.LBA_partition_start );
}
// Find the super block
uint16_t superBlock[256];
ATA_DEVICE::Read(BUS_PORT::Primary, DEVICE_DRIVE::MASTER, mbr->TableEntries[0].LBA_partition_start, superBlock);
BiosParameterBlock* bpb = (BiosParameterBlock*) superBlock;
printf("\nBPB: Bytes per Sector %d\n", bpb->BytesPerSector );
printf("OEM ID: %s\n", bpb->OEM_id);
printf("Bytes per sector: %d\n", bpb->BytesPerSector);
printf("Sectors per cluster: %d\n", bpb->SectorsPerCluster);
printf("Reserved sectors: %d\n", bpb->ReservedSectors);
printf("Number of FAT: %d\n", bpb->NumberOfFileAllocationTables);
printf("Number of Dir entries: %d\n", bpb->NumberOfDirectoryEntries);
printf("Total Sectors in volume: %d\n", bpb->TotalSectorsInLogicalVolume);
printf("Sectors per FAT: %d\n", bpb->NumberOfSectorsPerFAT);
uint32_t PartitionAddress = mbr->TableEntries[0].LBA_partition_start *512 ;
uint32_t RootDirAddress = PartitionAddress + ((bpb->ReservedSectors + bpb->NumberOfSectorsPerFAT * bpb->NumberOfFileAllocationTables ) * bpb->BytesPerSector);
uint32_t RootDirLBA =RootDirAddress/512;
uint16_t RootDir [16];
ATA_DEVICE::Read(BUS_PORT::Primary, DEVICE_DRIVE::MASTER,RootDirLBA, (uint16_t*) RootDir );
while (true){
//Read time indefinetely
read_rtc();
printf( "UTC time: %02d-%02d-%02d %02d:%02d:%02d [ Formatted as YY-MM-DD h:mm:ss]\r" ,year, month, day, hour, minute, second);
delay(1000);
}
}