ide-floppy.c

ep9315平台下硬盘驱动的源码

		if (status.b.check || test_bit(PC_DMA_ERROR, &pc->flags)) {
			/* Error detected */
#if IDEFLOPPY_DEBUG_LOG
			printk(KERN_INFO "ide-floppy: %s: I/O error\n",
				drive->name);
#endif /* IDEFLOPPY_DEBUG_LOG */
			rq->errors++;
			if (pc->c[0] == IDEFLOPPY_REQUEST_SENSE_CMD) {
				printk(KERN_ERR "ide-floppy: I/O error in "
					"request sense command\n");
				return ide_do_reset(drive);
			}
			/* Retry operation */
			idefloppy_retry_pc(drive);
			/* queued, but not started */
			return ide_stopped;
		}
		pc->error = 0;
		if (floppy->failed_pc == pc)
			floppy->failed_pc = NULL;
		/* Command finished - Call the callback function */
		pc->callback(drive);
		return ide_stopped;
	}
#ifdef CONFIG_BLK_DEV_IDEDMA
	if (test_and_clear_bit(PC_DMA_IN_PROGRESS, &pc->flags)) {
		printk(KERN_ERR "ide-floppy: The floppy wants to issue "
			"more interrupts in DMA mode\n");
		(void) HWIF(drive)->ide_dma_off(drive);
		return ide_do_reset(drive);
	}
#endif /* CONFIG_BLK_DEV_IDEDMA */
	/* Get the number of bytes to transfer */
	bcount.b.high = HWIF(drive)->INB(IDE_BCOUNTH_REG);
	bcount.b.low = HWIF(drive)->INB(IDE_BCOUNTL_REG);
	/* on this interrupt */
	ireason.all = HWIF(drive)->INB(IDE_IREASON_REG);

	if (ireason.b.cod) {
		printk(KERN_ERR "ide-floppy: CoD != 0 in idefloppy_pc_intr\n");
		return ide_do_reset(drive);
	}
	if (ireason.b.io == test_bit(PC_WRITING, &pc->flags)) {
		/* Hopefully, we will never get here */
		printk(KERN_ERR "ide-floppy: We wanted to %s, ",
			ireason.b.io ? "Write":"Read");
		printk(KERN_ERR "but the floppy wants us to %s !\n",
			ireason.b.io ? "Read":"Write");
		return ide_do_reset(drive);
	}
	if (!test_bit(PC_WRITING, &pc->flags)) {
		/* Reading - Check that we have enough space */
		temp = pc->actually_transferred + bcount.all;
		if (temp > pc->request_transfer) {
			if (temp > pc->buffer_size) {
				printk(KERN_ERR "ide-floppy: The floppy wants "
					"to send us more data than expected "
					"- discarding data\n");
				idefloppy_discard_data(drive,bcount.all);
				if (HWGROUP(drive)->handler != NULL)
					BUG();
				ide_set_handler(drive,
						&idefloppy_pc_intr,
						IDEFLOPPY_WAIT_CMD,
						NULL);
				return ide_started;
			}
#if IDEFLOPPY_DEBUG_LOG
			printk(KERN_NOTICE "ide-floppy: The floppy wants to "
				"send us more data than expected - "
				"allowing transfer\n");
#endif /* IDEFLOPPY_DEBUG_LOG */
		}
	}
	if (test_bit(PC_WRITING, &pc->flags)) {
		if (pc->buffer != NULL)
			/* Write the current buffer */
			HWIF(drive)->atapi_output_bytes(drive,
						pc->current_position,
						bcount.all);
		else
			idefloppy_output_buffers(drive, pc, bcount.all);
	} else {
		if (pc->buffer != NULL)
			/* Read the current buffer */
			HWIF(drive)->atapi_input_bytes(drive,
						pc->current_position,
						bcount.all);
		else
			idefloppy_input_buffers(drive, pc, bcount.all);
	}
	/* Update the current position */
	pc->actually_transferred += bcount.all;
	pc->current_position += bcount.all;

	if (HWGROUP(drive)->handler != NULL)
		BUG();
	ide_set_handler(drive, &idefloppy_pc_intr, IDEFLOPPY_WAIT_CMD, NULL);		/* And set the interrupt handler again */
	return ide_started;
}

/*
 * This is the original routine that did the packet transfer.
 * It fails at high speeds on the Iomega ZIP drive, so there's a slower version
 * for that drive below. The algorithm is chosen based on drive type
 */
static ide_startstop_t idefloppy_transfer_pc (ide_drive_t *drive)
{
	ide_startstop_t startstop;
	idefloppy_floppy_t *floppy = drive->driver_data;
	atapi_ireason_t ireason;

	if (ide_wait_stat(&startstop, drive, DRQ_STAT, BUSY_STAT, WAIT_READY)) {
		printk(KERN_ERR "ide-floppy: Strange, packet command "
				"initiated yet DRQ isn't asserted\n");
		return startstop;
	}
	ireason.all = HWIF(drive)->INB(IDE_IREASON_REG);
	if (!ireason.b.cod || ireason.b.io) {
		printk(KERN_ERR "ide-floppy: (IO,CoD) != (0,1) while "
				"issuing a packet command\n");
		return ide_do_reset(drive);
	}
	if (HWGROUP(drive)->handler != NULL)
		BUG();
	/* Set the interrupt routine */
	ide_set_handler(drive, &idefloppy_pc_intr, IDEFLOPPY_WAIT_CMD, NULL);
	/* Send the actual packet */
	HWIF(drive)->atapi_output_bytes(drive, floppy->pc->c, 12);
	return ide_started;
}


/*
 * What we have here is a classic case of a top half / bottom half
 * interrupt service routine. In interrupt mode, the device sends
 * an interrupt to signal it's ready to receive a packet. However,
 * we need to delay about 2-3 ticks before issuing the packet or we
 * gets in trouble.
 *
 * So, follow carefully. transfer_pc1 is called as an interrupt (or
 * directly). In either case, when the device says it's ready for a 
 * packet, we schedule the packet transfer to occur about 2-3 ticks
 * later in transfer_pc2.
 */
static int idefloppy_transfer_pc2 (ide_drive_t *drive)
{
	idefloppy_floppy_t *floppy = drive->driver_data;

	/* Send the actual packet */
	HWIF(drive)->atapi_output_bytes(drive, floppy->pc->c, 12);
	/* Timeout for the packet command */
	return IDEFLOPPY_WAIT_CMD;
}

static ide_startstop_t idefloppy_transfer_pc1 (ide_drive_t *drive)
{
	idefloppy_floppy_t *floppy = drive->driver_data;
	ide_startstop_t startstop;
	atapi_ireason_t ireason;

	if (ide_wait_stat(&startstop, drive, DRQ_STAT, BUSY_STAT, WAIT_READY)) {
		printk(KERN_ERR "ide-floppy: Strange, packet command "
				"initiated yet DRQ isn't asserted\n");
		return startstop;
	}
	ireason.all = HWIF(drive)->INB(IDE_IREASON_REG);
	if (!ireason.b.cod || ireason.b.io) {
		printk(KERN_ERR "ide-floppy: (IO,CoD) != (0,1) "
				"while issuing a packet command\n");
		return ide_do_reset(drive);
	}
	/* 
	 * The following delay solves a problem with ATAPI Zip 100 drives
	 * where the Busy flag was apparently being deasserted before the
	 * unit was ready to receive data. This was happening on a
	 * 1200 MHz Athlon system. 10/26/01 25msec is too short,
	 * 40 and 50msec work well. idefloppy_pc_intr will not be actually
	 * used until after the packet is moved in about 50 msec.
	 */
	if (HWGROUP(drive)->handler != NULL)
		BUG();
	ide_set_handler(drive, 
	  &idefloppy_pc_intr, 		/* service routine for packet command */
	  floppy->ticks,		/* wait this long before "failing" */
	  &idefloppy_transfer_pc2);	/* fail == transfer_pc2 */
	return ide_started;
}

/*
 *	Issue a packet command
 */
static ide_startstop_t idefloppy_issue_pc (ide_drive_t *drive, idefloppy_pc_t *pc)
{
	idefloppy_floppy_t *floppy = drive->driver_data;
	atapi_feature_t feature;
	atapi_bcount_t bcount;
	ide_handler_t *pkt_xfer_routine;

#if IDEFLOPPY_DEBUG_BUGS
	if (floppy->pc->c[0] == IDEFLOPPY_REQUEST_SENSE_CMD &&
	    pc->c[0] == IDEFLOPPY_REQUEST_SENSE_CMD) {
		printk(KERN_ERR "ide-floppy: possible ide-floppy.c bug - "
			"Two request sense in serial were issued\n");
	}
#endif /* IDEFLOPPY_DEBUG_BUGS */

	if (floppy->failed_pc == NULL &&
	    pc->c[0] != IDEFLOPPY_REQUEST_SENSE_CMD)
		floppy->failed_pc = pc;
	/* Set the current packet command */
	floppy->pc = pc;

	if (pc->retries > IDEFLOPPY_MAX_PC_RETRIES ||
	    test_bit(PC_ABORT, &pc->flags)) {
		/*
		 *	We will "abort" retrying a packet command in case
		 *	a legitimate error code was received.
		 */
		if (!test_bit(PC_ABORT, &pc->flags)) {
			if (!test_bit(PC_SUPPRESS_ERROR, &pc->flags)) {
				printk(KERN_ERR "ide-floppy: %s: I/O error, "
						"pc = %2x, key = %2x, "
						"asc = %2x, ascq = %2x\n",
						drive->name, pc->c[0],
						floppy->sense_key,
						floppy->asc, floppy->ascq);
			}
			/* Giving up */
			pc->error = IDEFLOPPY_ERROR_GENERAL;
		}
		floppy->failed_pc = NULL;
		pc->callback(drive);
		return ide_stopped;
	}
#if IDEFLOPPY_DEBUG_LOG
	printk (KERN_INFO "Retry number - %d\n", pc->retries);
#endif /* IDEFLOPPY_DEBUG_LOG */

	pc->retries++;
	/* We haven't transferred any data yet */
	pc->actually_transferred = 0;
	pc->current_position = pc->buffer;
	bcount.all = IDE_MIN(pc->request_transfer, 63 * 1024);

#ifdef CONFIG_BLK_DEV_IDEDMA
	if (test_and_clear_bit(PC_DMA_ERROR, &pc->flags)) {
		(void) HWIF(drive)->ide_dma_off(drive);
	}
#endif /* CONFIG_BLK_DEV_IDEDMA */
	feature.all = 0;
#ifdef CONFIG_BLK_DEV_IDEDMA
	if (test_bit(PC_DMA_RECOMMENDED, &pc->flags) && drive->using_dma) {
		if (test_bit(PC_WRITING, &pc->flags)) {
			feature.b.dma = !HWIF(drive)->ide_dma_write(drive);
		} else {
			feature.b.dma = !HWIF(drive)->ide_dma_read(drive);
		}
	}
#endif /* CONFIG_BLK_DEV_IDEDMA */

	if (IDE_CONTROL_REG)
		HWIF(drive)->OUTB(drive->ctl, IDE_CONTROL_REG);
	/* Use PIO/DMA */
	HWIF(drive)->OUTB(feature.all, IDE_FEATURE_REG);
	HWIF(drive)->OUTB(bcount.b.high, IDE_BCOUNTH_REG);
	HWIF(drive)->OUTB(bcount.b.low, IDE_BCOUNTL_REG);
	HWIF(drive)->OUTB(drive->select.all, IDE_SELECT_REG);

#ifdef CONFIG_BLK_DEV_IDEDMA
	if (feature.b.dma) {	/* Begin DMA, if necessary */
		set_bit(PC_DMA_IN_PROGRESS, &pc->flags);
		(void) (HWIF(drive)->ide_dma_begin(drive));
	}
#endif /* CONFIG_BLK_DEV_IDEDMA */

	/* Can we transfer the packet when we get the interrupt or wait? */
	if (test_bit(IDEFLOPPY_ZIP_DRIVE, &floppy->flags)) {
		/* wait */
		pkt_xfer_routine = &idefloppy_transfer_pc1;
	} else {
		/* immediate */
		pkt_xfer_routine = &idefloppy_transfer_pc;
	}
	
	if (test_bit(IDEFLOPPY_DRQ_INTERRUPT, &floppy->flags)) {
		/* Issue the packet command */
		ide_execute_command(drive, WIN_PACKETCMD, 
				pkt_xfer_routine,
				IDEFLOPPY_WAIT_CMD,
				NULL);
		return ide_started;
	} else {
		/* Issue the packet command */
		HWIF(drive)->OUTB(WIN_PACKETCMD, IDE_COMMAND_REG);
		return (*pkt_xfer_routine) (drive);
	}
}

static void idefloppy_rw_callback (ide_drive_t *drive)
{
#if IDEFLOPPY_DEBUG_LOG	
	printk (KERN_INFO "ide-floppy: Reached idefloppy_rw_callback\n");
#endif /* IDEFLOPPY_DEBUG_LOG */

	idefloppy_do_end_request(drive, 1);
	return;
}

static void idefloppy_create_prevent_cmd (idefloppy_pc_t *pc, int prevent)
{
#if IDEFLOPPY_DEBUG_LOG
	printk(KERN_INFO "ide-floppy: creating prevent removal command, "
		"prevent = %d\n", prevent);
#endif /* IDEFLOPPY_DEBUG_LOG */

	idefloppy_init_pc(pc);
	pc->c[0] = IDEFLOPPY_PREVENT_REMOVAL_CMD;
	pc->c[4] = prevent;
}

static void idefloppy_create_read_capacity_cmd (idefloppy_pc_t *pc)
{
	idefloppy_init_pc(pc);
	pc->c[0] = IDEFLOPPY_READ_CAPACITY_CMD;
	pc->c[7] = 255;
	pc->c[8] = 255;
	pc->request_transfer = 255;
}

static void idefloppy_create_format_unit_cmd (idefloppy_pc_t *pc, int b, int l,
					      int flags)
{
	idefloppy_init_pc(pc);
	pc->c[0] = IDEFLOPPY_FORMAT_UNIT_CMD;
	pc->c[1] = 0x17;

	memset(pc->buffer, 0, 12);
	pc->buffer[1] = 0xA2;
	/* Default format list header, u8 1: FOV/DCRT/IMM bits set */

	if (flags & 1)				/* Verify bit on... */
		pc->buffer[1] ^= 0x20;		/* ... turn off DCRT bit */
	pc->buffer[3] = 8;

	put_unaligned(htonl(b), (unsigned int *)(&pc->buffer[4]));
	put_unaligned(htonl(l), (unsigned int *)(&pc->buffer[8]));
	pc->buffer_size=12;
	set_bit(PC_WRITING, &pc->flags);
}

/*
 *	A mode sense command is used to "sense" floppy parameters.
 */
static void idefloppy_create_mode_sense_cmd (idefloppy_pc_t *pc, u8 page_code, u8 type)
{
	u16 length = sizeof(idefloppy_mode_parameter_header_t);
	
	idefloppy_init_pc(pc);
	pc->c[0] = IDEFLOPPY_MODE_SENSE_CMD;
	pc->c[1] = 0;
	pc->c[2] = page_code + (type << 6);

	switch (page_code) {
		case IDEFLOPPY_CAPABILITIES_PAGE:
			length += 12;
			break;
		case IDEFLOPPY_FLEXIBLE_DISK_PAGE:
			length += 32;
			break;
		default:
			printk(KERN_ERR "ide-floppy: unsupported page code "
				"in create_mode_sense_cmd\n");
	}
	put_unaligned(htons(length), (u16 *) &pc->c[7]);
	pc->request_transfer = length;
}

static void idefloppy_create_start_stop_cmd (idefloppy_pc_t *pc, int start)
{
	idefloppy_init_pc(pc);
	pc->c[0] = IDEFLOPPY_START_STOP_CMD;
	pc->c[4] = start;
}

static void idefloppy_create_test_unit_ready_cmd(idefloppy_pc_t *pc)
{
	idefloppy_init_pc(pc);
	pc->c[0] = IDEFLOPPY_TEST_UNIT_READY_CMD;
}

static void idefloppy_create_rw_cmd (idefloppy_floppy_t *floppy, idefloppy_pc_t *pc, struct request *rq, unsigned long sector)
{
	int block = sector / floppy->bs_factor;
	int blocks = rq->nr_sectors / floppy->bs_factor;
	
#if IDEFLOPPY_DEBUG_LOG
	printk("create_rw1%d_cmd: block == %d, blocks == %d\n",
		2 * test_bit(IDEFLOPPY_USE_READ12, &floppy->flags),
		block, blocks);
#endif /* IDEFLOPPY_DEBUG_LOG */

	idefloppy_init_pc(pc);
	if (test_bit(IDEFLOPPY_USE_READ12, &floppy->flags)) {
		pc->c[0] = rq->cmd == READ ? IDEFLOPPY_READ12_CMD : IDEFLOPPY_WRITE12_CMD;
		put_unaligned(htonl(blocks), (unsigned int *) &pc->c[6]);
	} else {
		pc->c[0] = rq->cmd == READ ? IDEFLOPPY_READ10_CMD : IDEFLOPPY_WRITE10_CMD;
		put_unaligned(htons(blocks), (u16 *) &pc->c[7]);
	}
	put_unaligned(htonl(block), (unsigned int *) &pc->c[2]);
	pc->callback = &idefloppy_rw_callback;
	pc->rq = rq;
	pc->b_data = rq->buffer;
	pc->b_count = rq->cmd == READ ? 0 : rq->bh->b_size;
	if (rq->cmd == WRITE)
		set_bit(PC_WRITING, &pc->flags);
	pc->buffer = NULL;