/* ATA.c - This file is a part of NutsOS
 *
 * NutsOS
 * Copyright (C) 2013  Free Software Foundation, Inc.
 *
 * NutsOS is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 3 of the License, or
 * (at your option) any later version.
 *
 * NutsOS is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with NutsOS; If not, see <http://www.gnu.org/licenses/>.
 *
 * Valentin Verdier <valentin.verdier03@gmail.com>
 */

#include "../types.h"
#include "../kernLdr.h"

#include "ATA.h"

int ATA_getDevice(unsigned int ataNumber, unsigned int drive, T_ATA_device* dev) {
	ataNumber &= 0x3;
	drive &= 0x1;

	print("-> Device : ATA %d ", DEFAULT_COLOR, ataNumber);
	switch(ataNumber) {
		case 0:
			dev->ata_port = ATA_0_PORT;
			dev->ata_ctrl_port = ATA_0_CTRL_PORT;
			break;

		case 1:
			dev->ata_port = ATA_1_PORT;
			dev->ata_ctrl_port = ATA_1_CTRL_PORT;
			break;

		case 2:
			dev->ata_port = ATA_2_PORT;
			dev->ata_ctrl_port = ATA_2_CTRL_PORT;
			break;

		case 3:
			dev->ata_port = ATA_3_PORT;
			dev->ata_ctrl_port = ATA_3_CTRL_PORT;
			break;
	}

	if(drive) {
		print("Slave drive\n", DEFAULT_COLOR);
		dev->drive = ATA_SLAVE;
	} else {
		print("Master drive\n", DEFAULT_COLOR);
		dev->drive = ATA_MASTER;
	}

	/* On vérifie si les ports I/O sont reliés à un contrôleur */
	T_byte testByte;
	_out(dev->ata_port + 2, 0x45);
	_in(dev->ata_port + 2, &testByte);

	if(testByte == 0x45) { /* Le contrôleur éxiste */
		T_byte a, b, status;

		/* On se prépare à utiliser la commande IDENTIFY pour connaitre le type de disque ATA */
		_out(dev->ata_port + 6, ATA_CHS_MODE | dev->drive); /* On selectionne le disque */
		delay(1000);

		_out(dev->ata_port + 2, 0);
		_out(dev->ata_port + 3, 0);
		_out(dev->ata_port + 4, 0);
		_out(dev->ata_port + 5, 0);

		_out(dev->ata_port + 7, ATA_CMD_IDENTIFY); /* envoie de la commande */

		_in(dev->ata_port + 7, &status);

		if(status == 0) { /* Si le status est à 0, il n'y à pas de disque */
			print("-> ERROR : Drive doesn't exist !\n", DEFAULT_COLOR);
			return 0;
		} else { /* Sinon on attend que le disque soit prêt */
			while(status & 0x80) {
				_in(dev->ata_port + 7, &status);
			}
		}

		/* On récupère les octets de signature */
		_in(dev->ata_port + 4, &a);
		_in(dev->ata_port + 5, &b);

		if((a == 0) && (b == 0)) { /* Disque dur ATA */
			while(!(status & 0x08)) { /* On attend que le disque soit prêt pour la lecture des données d'identification */
				_in(dev->ata_port + 7, &status);
			}

			unsigned int i;
			T_word trash;
			for(i = 0; i < 256; i++) { /* Pas besoin des info d'identification, mais on les transfert pour que le contrôleur termine la commande normalement */
				_inw(dev->ata_port, &trash);
			}

			return 1;
		} else {
			print("-> ERROR : Drive is not ATA !\n", DEFAULT_COLOR);
		}
	} else {
		print("-> ERROR :  Controller doesn't exist !\n", DEFAULT_COLOR);
	}
	return 0;
}


void ATA_read(T_ATA_device dev, T_dword baseLBA, T_byte sectorCount, void* baddr) {
	T_byte* buffer = baddr;
	T_byte status = 0;
	unsigned int i, j;
	T_word word;

	_out(dev.ata_port + 1, 0); /* Octet nul */
	_out(dev.ata_port + 2, sectorCount);
	_out(dev.ata_port + 3, (T_byte) (baseLBA & 0xFF)); /* 8 bits de poids faible de l'adresse LBA */
	_out(dev.ata_port + 4, (T_byte) ((baseLBA >> 8) & 0xFF));
	_out(dev.ata_port + 5, (T_byte) ((baseLBA >> 16) & 0xFF));

	_out(dev.ata_port + 6, ATA_LBA_MODE | dev.drive | ((baseLBA >> 24) & 0x0F));
	for(i = 0; i < 4; i++) {
		_in(dev.ata_port + 7, &status);
	}

	_out(dev.ata_port + 7, ATA_CMD_READ);

	/* On attend que le contrôleur soit prêt */

	for(i = 0; i < sectorCount; i++) {
		do {
			_in(dev.ata_port + 7, &status);
		}while((status & 0x80) || !(status & 0x08));

		for(j = 0; j < 256; j++) {
			_inw(dev.ata_port, &word);
			buffer[(i * 512) + (j * 2)] = (T_byte) (word & 0xFF);
			buffer[(i * 512) + (j * 2) + 1] = (T_byte) ((word >> 8) & 0xFF);
		}
	}
}