path: root/drivers/firewire/fw-sbp2.c

/*
 * SBP2 driver (SCSI over IEEE1394)
 *
 * Copyright (C) 2005-2007  Kristian Hoegsberg <krh@bitplanet.net>
 *
 * This program 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 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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 this program; if not, write to the Free Software Foundation,
 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

/*
 * The basic structure of this driver is based on the old storage driver,
 * drivers/ieee1394/sbp2.c, originally written by
 *     James Goodwin <jamesg@filanet.com>
 * with later contributions and ongoing maintenance from
 *     Ben Collins <bcollins@debian.org>,
 *     Stefan Richter <stefanr@s5r6.in-berlin.de>
 * and many others.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
#include <linux/device.h>
#include <linux/scatterlist.h>
#include <linux/dma-mapping.h>
#include <linux/blkdev.h>
#include <linux/timer.h>

#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_dbg.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_host.h>

#include "fw-transaction.h"
#include "fw-topology.h"
#include "fw-device.h"

/* I don't know why the SCSI stack doesn't define something like this... */
typedef void (*scsi_done_fn_t)(struct scsi_cmnd *);

static const char sbp2_driver_name[] = "sbp2";

struct sbp2_device {
	struct kref kref;
	struct fw_unit *unit;
	struct fw_address_handler address_handler;
	struct list_head orb_list;
	u64 management_agent_address;
	u64 command_block_agent_address;
	u32 workarounds;
	int login_id;

	/*
	 * We cache these addresses and only update them once we've
	 * logged in or reconnected to the sbp2 device.  That way, any
	 * IO to the device will automatically fail and get retried if
	 * it happens in a window where the device is not ready to
	 * handle it (e.g. after a bus reset but before we reconnect).
	 */
	int node_id;
	int address_high;
	int generation;

	int retries;
	struct delayed_work work;
};

#define SBP2_MAX_SG_ELEMENT_LENGTH	0xf000
#define SBP2_MAX_SECTORS		255	/* Max sectors supported */
#define SBP2_ORB_TIMEOUT		2000	/* Timeout in ms */

#define SBP2_ORB_NULL			0x80000000

#define SBP2_DIRECTION_TO_MEDIA		0x0
#define SBP2_DIRECTION_FROM_MEDIA	0x1

/* Unit directory keys */
#define SBP2_COMMAND_SET_SPECIFIER	0x38
#define SBP2_COMMAND_SET		0x39
#define SBP2_COMMAND_SET_REVISION	0x3b
#define SBP2_FIRMWARE_REVISION		0x3c

/* Flags for detected oddities and brokeness */
#define SBP2_WORKAROUND_128K_MAX_TRANS	0x1
#define SBP2_WORKAROUND_INQUIRY_36	0x2
#define SBP2_WORKAROUND_MODE_SENSE_8	0x4
#define SBP2_WORKAROUND_FIX_CAPACITY	0x8
#define SBP2_WORKAROUND_OVERRIDE	0x100

/* Management orb opcodes */
#define SBP2_LOGIN_REQUEST		0x0
#define SBP2_QUERY_LOGINS_REQUEST	0x1
#define SBP2_RECONNECT_REQUEST		0x3
#define SBP2_SET_PASSWORD_REQUEST	0x4
#define SBP2_LOGOUT_REQUEST		0x7
#define SBP2_ABORT_TASK_REQUEST		0xb
#define SBP2_ABORT_TASK_SET		0xc
#define SBP2_LOGICAL_UNIT_RESET		0xe
#define SBP2_TARGET_RESET_REQUEST	0xf

/* Offsets for command block agent registers */
#define SBP2_AGENT_STATE		0x00
#define SBP2_AGENT_RESET		0x04
#define SBP2_ORB_POINTER		0x08
#define SBP2_DOORBELL			0x10
#define SBP2_UNSOLICITED_STATUS_ENABLE	0x14

/* Status write response codes */
#define SBP2_STATUS_REQUEST_COMPLETE	0x0
#define SBP2_STATUS_TRANSPORT_FAILURE	0x1
#define SBP2_STATUS_ILLEGAL_REQUEST	0x2
#define SBP2_STATUS_VENDOR_DEPENDENT	0x3

#define STATUS_GET_ORB_HIGH(v)		((v).status & 0xffff)
#define STATUS_GET_SBP_STATUS(v)	(((v).status >> 16) & 0xff)
#define STATUS_GET_LEN(v)		(((v).status >> 24) & 0x07)
#define STATUS_GET_DEAD(v)		(((v).status >> 27) & 0x01)
#define STATUS_GET_RESPONSE(v)		(((v).status >> 28) & 0x03)
#define STATUS_GET_SOURCE(v)		(((v).status >> 30) & 0x03)
#define STATUS_GET_ORB_LOW(v)		((v).orb_low)
#define STATUS_GET_DATA(v)		((v).data)

struct sbp2_status {
	u32 status;
	u32 orb_low;
	u8 data[24];
};

struct sbp2_pointer {
	u32 high;
	u32 low;
};

struct sbp2_orb {
	struct fw_transaction t;
	dma_addr_t request_bus;
	int rcode;
	struct sbp2_pointer pointer;
	void (*callback)(struct sbp2_orb * orb, struct sbp2_status * status);
	struct list_head link;
};

#define MANAGEMENT_ORB_LUN(v)			((v))
#define MANAGEMENT_ORB_FUNCTION(v)		((v) << 16)
#define MANAGEMENT_ORB_RECONNECT(v)		((v) << 20)
#define MANAGEMENT_ORB_EXCLUSIVE		((1) << 28)
#define MANAGEMENT_ORB_REQUEST_FORMAT(v)	((v) << 29)
#define MANAGEMENT_ORB_NOTIFY			((1) << 31)

#define MANAGEMENT_ORB_RESPONSE_LENGTH(v)	((v))
#define MANAGEMENT_ORB_PASSWORD_LENGTH(v)	((v) << 16)

struct sbp2_management_orb {
	struct sbp2_orb base;
	struct {
		struct sbp2_pointer password;
		struct sbp2_pointer response;
		u32 misc;
		u32 length;
		struct sbp2_pointer status_fifo;
	} request;
	__be32 response[4];
	dma_addr_t response_bus;
	struct completion done;
	struct sbp2_status status;
};

#define LOGIN_RESPONSE_GET_LOGIN_ID(v)	((v).misc & 0xffff)
#define LOGIN_RESPONSE_GET_LENGTH(v)	(((v).misc >> 16) & 0xffff)

struct sbp2_login_response {
	u32 misc