ide-disk.c

ep9315平台下硬盘驱动的源码

			return startstop;
		}
		if (!drive->unmask)
			local_irq_disable();
		if (drive->mult_count) {
			ide_hwgroup_t *hwgroup = HWGROUP(drive);
	/*
	 * Ugh.. this part looks ugly because we MUST set up
	 * the interrupt handler before outputting the first block
	 * of data to be written.  If we hit an error (corrupted buffer list)
	 * in ide_multwrite(), then we need to remove the handler/timer
	 * before returning.  Fortunately, this NEVER happens (right?).
	 *
	 * Except when you get an error it seems...
	 *
	 * MAJOR DATA INTEGRITY BUG !!! only if we error 
	 */
			hwgroup->wrq = *rq; /* scratchpad */
			ide_set_handler(drive, &multwrite_intr, WAIT_CMD, NULL);
			if (ide_multwrite(drive, drive->mult_count)) {
				unsigned long flags;
				spin_lock_irqsave(&io_request_lock, flags);
				hwgroup->handler = NULL;
				del_timer(&hwgroup->timer);
				spin_unlock_irqrestore(&io_request_lock, flags);
				return ide_stopped;
			}
		} else {
			unsigned long flags;
			char *to = ide_map_buffer(rq, &flags);
			ide_set_handler(drive, &write_intr, WAIT_CMD, NULL);
			taskfile_output_data(drive, to, SECTOR_WORDS);
			ide_unmap_buffer(to, &flags);
		}
		return ide_started;
	}
	printk(KERN_ERR "%s: bad command: %d\n", drive->name, rq->cmd);
	idedisk_end_request(drive, 0);
	return ide_stopped;
}


#else /* CONFIG_IDE_TASKFILE_IO */

static ide_startstop_t chs_rw_disk(ide_drive_t *, struct request *, unsigned long);
static ide_startstop_t lba_28_rw_disk(ide_drive_t *, struct request *, unsigned long);
static ide_startstop_t lba_48_rw_disk(ide_drive_t *, struct request *, unsigned long long);

/*
 * __ide_do_rw_disk() issues READ and WRITE commands to a disk,
 * using LBA if supported, or CHS otherwise, to address sectors.
 * It also takes care of issuing special DRIVE_CMDs.
 */
ide_startstop_t __ide_do_rw_disk (ide_drive_t *drive, struct request *rq, unsigned long block)
{
	if (!blk_fs_request(rq)) {
		printk(KERN_ERR "%s: bad command: %d\n", drive->name, rq->cmd);
		idedisk_end_request(drive, 0);
		return ide_stopped;
	}

	/*
	 * 268435455  == 137439 MB or 28bit limit
	 *
	 * need to add split taskfile operations based on 28bit threshold.
	 */

	if (drive->addressing == 1)		/* 48-bit LBA */
		return lba_48_rw_disk(drive, rq, (unsigned long long) block);
	if (drive->select.b.lba)		/* 28-bit LBA */
		return lba_28_rw_disk(drive, rq, (unsigned long) block);

	/* 28-bit CHS : DIE DIE DIE piece of legacy crap!!! */
	return chs_rw_disk(drive, rq, (unsigned long) block);
}

static task_ioreg_t get_command (ide_drive_t *drive, int cmd)
{
	int lba48bit = (drive->id->cfs_enable_2 & 0x0400) ? 1 : 0;

#if 1
	lba48bit = (drive->addressing == 1) ? 1 : 0;
#endif

	if ((cmd == READ) && (drive->using_dma))
		return (lba48bit) ? WIN_READDMA_EXT : WIN_READDMA;
	else if ((cmd == READ) && (drive->mult_count))
		return (lba48bit) ? WIN_MULTREAD_EXT : WIN_MULTREAD;
	else if (cmd == READ)
		return (lba48bit) ? WIN_READ_EXT : WIN_READ;
	else if ((cmd == WRITE) && (drive->using_dma))
		return (lba48bit) ? WIN_WRITEDMA_EXT : WIN_WRITEDMA;
	else if ((cmd == WRITE) && (drive->mult_count))
		return (lba48bit) ? WIN_MULTWRITE_EXT : WIN_MULTWRITE;
	else if (cmd == WRITE)
		return (lba48bit) ? WIN_WRITE_EXT : WIN_WRITE;
	else
		return WIN_NOP;
}

static ide_startstop_t chs_rw_disk (ide_drive_t *drive, struct request *rq, unsigned long block)
{
	ide_task_t		args;
	int			sectors;
	ata_nsector_t		nsectors;
	task_ioreg_t command	= get_command(drive, rq_data_dir(rq));
	unsigned int track	= (block / drive->sect);
	unsigned int sect	= (block % drive->sect) + 1;
	unsigned int head	= (track % drive->head);
	unsigned int cyl	= (track / drive->head);

	nsectors.all = (u16) rq->nr_sectors;
#ifdef DEBUG
	printk("%s: %sing: ", drive->name, (rq_data_dir(rq)==READ) ? "read" : "writ");
	printk("CHS=%d/%d/%d, ", cyl, head, sect);
	printk("sectors=%ld, ", rq->nr_sectors);
	printk("buffer=0x%08lx\n", (unsigned long) rq->buffer);
#endif

	memset(&args, 0, sizeof(ide_task_t));

	sectors	= (rq->nr_sectors == 256) ? 0x00 : rq->nr_sectors;
	args.tfRegister[IDE_NSECTOR_OFFSET]	= sectors;
	args.tfRegister[IDE_SECTOR_OFFSET]	= sect;
	args.tfRegister[IDE_LCYL_OFFSET]	= cyl;
	args.tfRegister[IDE_HCYL_OFFSET]	= (cyl>>8);
	args.tfRegister[IDE_SELECT_OFFSET]	= head;
	args.tfRegister[IDE_SELECT_OFFSET]	|= drive->select.all;
	args.tfRegister[IDE_COMMAND_OFFSET]	= command;
	args.command_type			= ide_cmd_type_parser(&args);
	args.rq					= (struct request *) rq;
	rq->special				= (ide_task_t *)&args;
	return do_rw_taskfile(drive, &args);
}

static ide_startstop_t lba_28_rw_disk (ide_drive_t *drive, struct request *rq, unsigned long block)
{
	ide_task_t		args;
	int			sectors;
	ata_nsector_t		nsectors;
	task_ioreg_t command	= get_command(drive, rq_data_dir(rq));

	nsectors.all = (u16) rq->nr_sectors;

#ifdef DEBUG
	printk("%s: %sing: ", drive->name, (rq_data_dir(rq)==READ) ? "read" : "writ");
	printk("LBAsect=%lld, ", block);
	printk("sectors=%ld, ", rq->nr_sectors);
	printk("buffer=0x%08lx\n", (unsigned long) rq->buffer);
#endif

	memset(&args, 0, sizeof(ide_task_t));

	sectors = (rq->nr_sectors == 256) ? 0x00 : rq->nr_sectors;
	args.tfRegister[IDE_NSECTOR_OFFSET]	= sectors;
	args.tfRegister[IDE_SECTOR_OFFSET]	= block;
	args.tfRegister[IDE_LCYL_OFFSET]	= (block>>=8);
	args.tfRegister[IDE_HCYL_OFFSET]	= (block>>=8);
	args.tfRegister[IDE_SELECT_OFFSET]	= ((block>>8)&0x0f);
	args.tfRegister[IDE_SELECT_OFFSET]	|= drive->select.all;
	args.tfRegister[IDE_COMMAND_OFFSET]	= command;
	args.command_type			= ide_cmd_type_parser(&args);
	args.rq					= (struct request *) rq;
	rq->special				= (ide_task_t *)&args;
	return do_rw_taskfile(drive, &args);
}

/*
 * 268435455  == 137439 MB or 28bit limit
 * 320173056  == 163929 MB or 48bit addressing
 * 1073741822 == 549756 MB or 48bit addressing fake drive
 */

static ide_startstop_t lba_48_rw_disk (ide_drive_t *drive, struct request *rq, unsigned long long block)
{
	ide_task_t		args;
	int			sectors;
	ata_nsector_t		nsectors;
	task_ioreg_t command	= get_command(drive, rq_data_dir(rq));

	nsectors.all = (u16) rq->nr_sectors;

#ifdef DEBUG
	printk("%s: %sing: ", drive->name, (rq_data_dir(rq)==READ) ? "read" : "writ");
	printk("LBAsect=%lld, ", block);
	printk("sectors=%ld, ", rq->nr_sectors);
	printk("buffer=0x%08lx\n", (unsigned long) rq->buffer);
#endif

	memset(&args, 0, sizeof(ide_task_t));

	sectors = (rq->nr_sectors == 65536) ? 0 : rq->nr_sectors;
	args.tfRegister[IDE_NSECTOR_OFFSET]	= sectors;
	args.tfRegister[IDE_SECTOR_OFFSET]	= block;	/* low lba */
	args.tfRegister[IDE_LCYL_OFFSET]	= (block>>=8);	/* mid lba */
	args.tfRegister[IDE_HCYL_OFFSET]	= (block>>=8);	/* hi  lba */
	args.tfRegister[IDE_SELECT_OFFSET]	= drive->select.all;
	args.tfRegister[IDE_COMMAND_OFFSET]	= command;
	args.hobRegister[IDE_NSECTOR_OFFSET_HOB]= sectors >> 8;
	args.hobRegister[IDE_SECTOR_OFFSET_HOB]	= (block>>=8);	/* low lba */
	args.hobRegister[IDE_LCYL_OFFSET_HOB]	= (block>>=8);	/* mid lba */
	args.hobRegister[IDE_HCYL_OFFSET_HOB]	= (block>>=8);	/* hi  lba */
	args.hobRegister[IDE_SELECT_OFFSET_HOB]	= drive->select.all;
	args.hobRegister[IDE_CONTROL_OFFSET_HOB]= (drive->ctl|0x80);
	args.command_type			= ide_cmd_type_parser(&args);
	args.rq					= (struct request *) rq;
	rq->special				= (ide_task_t *)&args;
	return do_rw_taskfile(drive, &args);
}

#endif /* CONFIG_IDE_TASKFILE_IO */

static ide_startstop_t ide_do_rw_disk (ide_drive_t *drive, struct request *rq, unsigned long block)
{
	ide_hwif_t *hwif	= HWIF(drive);
	if (hwif->rw_disk)
		return hwif->rw_disk(drive, rq, block);
	else 
		return __ide_do_rw_disk(drive, rq, block);
}

EXPORT_SYMBOL_GPL(__ide_do_rw_disk);

static int idedisk_open (struct inode *inode, struct file *filp, ide_drive_t *drive)
{
	MOD_INC_USE_COUNT;
	if (drive->removable && drive->usage == 1) {
		ide_task_t args;
		int cf;
		memset(&args, 0, sizeof(ide_task_t));
		args.tfRegister[IDE_COMMAND_OFFSET] = WIN_DOORLOCK;
		args.command_type = ide_cmd_type_parser(&args);
		check_disk_change(inode->i_rdev);
		/*
		 * Ignore the return code from door_lock,
		 * since the open() has already succeeded,
		 * and the door_lock is irrelevant at this point.
		 */
		if (drive->doorlocking && ide_raw_taskfile(drive, &args, NULL))
			drive->doorlocking = 0;
		drive->wcache = 0;
		/* Cache enabled ? */
		if (drive->id->csfo & 1)
			drive->wcache = 1;
		/* Cache command set available ? */
		if (drive->id->cfs_enable_1 & (1<<5))
			drive->wcache = 1;
		/* ATA6 cache extended commands */
		cf = drive->id->command_set_2 >> 24;
		if((cf & 0xC0) == 0x40 && (cf & 0x30) != 0)
			drive->wcache = 1;
	}
	return 0;
}

static int do_idedisk_flushcache(ide_drive_t *drive);

static int ide_cacheflush_p(ide_drive_t *drive)
{
	if(drive->wcache)
	{
		if (do_idedisk_flushcache(drive))
		{
			printk (KERN_INFO "%s: Write Cache FAILED Flushing!\n",
				drive->name);
			return -EIO;
		}
		return 1;
	}
	return 0;
}

static void idedisk_release (struct inode *inode, struct file *filp, ide_drive_t *drive)
{
	if (drive->removable && !drive->usage) {
		ide_task_t args;
		memset(&args, 0, sizeof(ide_task_t));
		args.tfRegister[IDE_COMMAND_OFFSET] = WIN_DOORUNLOCK;
		args.command_type = ide_cmd_type_parser(&args);
		invalidate_bdev(inode->i_bdev, 0);
		if (drive->doorlocking && ide_raw_taskfile(drive, &args, NULL))
			drive->doorlocking = 0;
	}
	ide_cacheflush_p(drive);
	MOD_DEC_USE_COUNT;
}

static int idedisk_media_change (ide_drive_t *drive)
{
	/* if removable, always assume it was changed */
	return drive->removable;
}

static void idedisk_revalidate (ide_drive_t *drive)
{
	grok_partitions(HWIF(drive)->gd, drive->select.b.unit,
			1<<PARTN_BITS,
			current_capacity(drive));
}

static int idedisk_end_request (ide_drive_t *drive, int uptodate)
{
	struct request *rq;
	unsigned long flags;
	int ret = 1;

	spin_lock_irqsave(&io_request_lock, flags);
	rq = HWGROUP(drive)->rq;

	/*
	 * decide whether to reenable DMA -- 3 is a random magic for now,
	 * if we DMA timeout more than 3 times, just stay in PIO
	 */
	if (drive->state == DMA_PIO_RETRY && drive->retry_pio <= 3) {
		drive->state = 0;
		HWGROUP(drive)->hwif->ide_dma_on(drive);
	}

	if (!end_that_request_first(rq, uptodate, drive->name)) {
		add_blkdev_randomness(MAJOR(rq->rq_dev));
		blkdev_dequeue_request(rq);
		HWGROUP(drive)->rq = NULL;
		end_that_request_last(rq);
		ret = 0;
	}

	spin_unlock_irqrestore(&io_request_lock, flags);
	return ret;
}

static u8 idedisk_dump_status (ide_drive_t *drive, const char *msg, u8 stat)
{
	ide_hwif_t *hwif = HWIF(drive);
	unsigned long flags;
	u8 err = 0;

	local_irq_set(flags);
	printk("%s: %s: status=0x%02x", drive->name, msg, stat);
#if FANCY_STATUS_DUMPS
	printk(" { ");
	if (stat & BUSY_STAT)
		printk("Busy ");
	else {
		if (stat & READY_STAT)	printk("DriveReady ");
		if (stat & WRERR_STAT)	printk("DeviceFault ");
		if (stat & SEEK_STAT)	printk("SeekComplete ");
		if (stat & DRQ_STAT)	printk("DataRequest ");
		if (stat & ECC_STAT)	printk("CorrectedError ");
		if (stat & INDEX_STAT)	printk("Index ");
		if (stat & ERR_STAT)	printk("Error ");
	}
	printk("}");
#endif	/* FANCY_STATUS_DUMPS */
	printk("\n");
	if ((stat & (BUSY_STAT|ERR_STAT)) == ERR_STAT) {
		err = hwif->INB(IDE_ERROR_REG);
		printk("%s: %s: error=0x%02x", drive->name, msg, err);
#if FANCY_STATUS_DUMPS
		printk(" { ");
		if (err & ABRT_ERR)	printk("DriveStatusError ");
		if (err & ICRC_ERR)
			printk("Bad%s ", (err & ABRT_ERR) ? "CRC" : "Sector");
		if (err & ECC_ERR)	printk("UncorrectableError ");
		if (err & ID_ERR)	printk("SectorIdNotFound ");
		if (err & TRK0_ERR)	printk("TrackZeroNotFound ");
		if (err & MARK_ERR)	printk("AddrMarkNotFound ");
		printk("}");
		if ((err & (BBD_ERR | ABRT_ERR)) == BBD_ERR ||
		    (err & (ECC_ERR|ID_ERR|MARK_ERR))) {
			if (drive->addressing == 1) {
				__u64 sectors = 0;
				u32 low = 0, high = 0;
				low = idedisk_read_24(drive);
				hwif->OUTB(drive->ctl|0x80, IDE_CONTROL_REG);
				high = idedisk_read_24(drive);
				sectors = ((__u64)high << 24) | low;
				printk(", LBAsect=%llu, high=%d, low=%d",
				       (unsigned long long) sectors,
				       high, low);
			} else {
				u8 cur = hwif->INB(IDE_SELECT_REG);
				if (cur & 0x40) {	/* using LBA? */
					printk(", LBAsect=%ld", (unsigned long)
					 ((cur&0xf)<<24)
					 |(hwif->INB(IDE_HCYL_REG)<<16)
					 |(hwif->INB(IDE_LCYL_REG)<<8)
					 | hwif->INB(IDE_SECTOR_REG));
				} else {
					printk(", CHS=%d/%d/%d",
					 (hwif->INB(IDE_HCYL_REG)<<8) +
					  hwif->INB(IDE_LCYL_REG),
					  cur & 0xf,
					  hwif->INB(IDE_SECTOR_REG));
				}
			}
			if (HWGROUP(drive) && HWGROUP(drive)->rq)
				printk(", sector=%ld",
					HWGROUP(drive)->rq->sector);
		}
	}
#endif	/* FANCY_STATUS_DUMPS */
	printk("\n");
	local_irq_restore(flags);
	return err;
}

ide_startstop_t idedisk_error (ide_drive_t *drive, const char *msg, u8 stat)
{
	ide_hwif_t *hwif;
	struct request *rq;
	u8 err;
	int i = (drive->mult_count ? drive->mult_count : 1) * SECTOR_WORDS;

	err = idedisk_dump_status(drive, msg, stat);

	if (drive == NULL || (rq = HWGROUP(drive)->rq) == NULL)
		return ide_stopped;

	hwif = HWIF(drive);
	/* retry only "normal" I/O: */
	switch (rq->cmd) {
		case IDE_DRIVE_CMD:
		case IDE_DRIVE_TASK:
		case IDE_DRIVE_TASKFILE:
			rq->errors = 1;
			ide_end_drive_cmd(drive, stat, err);
			return ide_stopped;
#if 0
		case IDE_DRIVE_TASKFILE:
			rq->errors = 1;
			ide_end_taskfile(drive, stat, err);
			return ide_stopped;
#endif
		default:
			break;
	}

	if (stat & BUSY_STAT || ((stat & WRERR_STAT) && !drive->nowerr)) {
		/* other bits are useless when BUSY */
		rq->errors |= ERROR_RESET;
	} else if (stat & ERR_STAT) {
		/* err has different meaning on cdrom and tape */
		if (err == ABRT_ERR) {
			if (drive->select.b.lba &&
			    /* some newer drives don't support WIN_SPECIFY */
			    hwif->INB(IDE_COMMAND_REG) == WIN_SPECIFY)
				return ide_stopped;
		} else if ((err & BAD_CRC) == BAD_CRC) {
			/* UDMA crc error, just retry the operation */
			drive->crc_count++;
		} else if (err & (BBD_ERR | ECC_ERR)) {
			/* retries won't help these */
			rq->errors = ERROR_MAX;
		} else if (err & TRK0_ERR) {
			/* help it find track zero */
			rq->errors |= ERROR_RECAL;
		}
	}
	if ((stat & DRQ_STAT) && rq_data_dir(rq) == READ) {
		/*
		 * try_to_flush_leftover_data() is invoked in response to
		 * a drive unexpectedly having its DRQ_STAT bit set.  As
		 * an alternative to resetting the drive, this routine
		 * tries to clear the condition by read a sector's worth
		 * of data from the drive.  Of course, this may not help
		 * if the drive is *waiting* for data from *us*.
		 */
		while (i > 0) {
			u32 buffer[16];
			unsigned int wcount = (i > 16) ? 16 : i;
			i -= wcount;
			taskfile_input_data(drive, buffer, wcount);
		}
	}
	if (hwif->INB(IDE_STATUS_REG) & (BUSY_STAT|DRQ_STAT)) {
		/* force an abort */
		hwif->OUTB(WIN_IDLEIMMEDIATE,IDE_COMMAND_REG);
	}
	if (rq->errors >= ERROR_MAX)
		DRIVER(drive)->end_request(drive, 0);
	else {
		if ((rq->errors & ERROR_RESET) == ERROR_RESET) {
			++rq->errors;
			return ide_do_reset(drive);