[linux-block.git] / drivers / scsi / aha152x.c

// SPDX-License-Identifier: GPL-2.0-or-later
/* aha152x.c -- Adaptec AHA-152x driver
 * Author: Jürgen E. Fischer, fischer@norbit.de
 * Copyright 1993-2004 Jürgen E. Fischer
 *
 * $Id: aha152x.c,v 2.7 2004/01/24 11:42:59 fischer Exp $
 *
 * $Log: aha152x.c,v $
 * Revision 2.7  2004/01/24 11:42:59  fischer
 * - gather code that is not used by PCMCIA at the end
 * - move request_region for !PCMCIA case to detection
 * - migration to new scsi host api (remove legacy code)
 * - free host scribble before scsi_done
 * - fix error handling
 * - one isapnp device added to id_table
 *
 * Revision 2.6  2003/10/30 20:52:47  fischer
 * - interfaces changes for kernel 2.6
 * - aha152x_probe_one introduced for pcmcia stub
 * - fixed pnpdev handling
 * - instead of allocation a new one, reuse command for request sense after check condition and reset
 * - fixes race in is_complete
 *
 * Revision 2.5  2002/04/14 11:24:53  fischer
 * - isapnp support
 * - abort fixed
 * - 2.5 support
 *
 * Revision 2.4  2000/12/16 12:53:56  fischer
 * - allow REQUEST SENSE to be queued
 * - handle shared PCI interrupts
 *
 * Revision 2.3  2000/11/04 16:40:26  fischer
 * - handle data overruns
 * - extend timeout for data phases
 *
 * Revision 2.2  2000/08/08 19:54:53  fischer
 * - minor changes
 *
 * Revision 2.1  2000/05/17 16:23:17  fischer
 * - signature update
 * - fix for data out w/o scatter gather
 *
 * Revision 2.0  1999/12/25 15:07:32  fischer
 * - interrupt routine completly reworked
 * - basic support for new eh code
 *
 * Revision 1.21  1999/11/10 23:46:36  fischer
 * - default to synchronous operation
 * - synchronous negotiation fixed
 * - added timeout to loops
 * - debugging output can be controlled through procfs
 *
 * Revision 1.20  1999/11/07 18:37:31  fischer
 * - synchronous operation works
 * - resid support for sg driver
 *
 * Revision 1.19  1999/11/02 22:39:59  fischer
 * - moved leading comments to README.aha152x
 * - new additional module parameters
 * - updates for 2.3
 * - support for the Tripace TC1550 controller
 * - interrupt handling changed
 *
 * Revision 1.18  1996/09/07 20:10:40  fischer
 * - fixed can_queue handling (multiple outstanding commands working again)
 *
 * Revision 1.17  1996/08/17 16:05:14  fischer
 * - biosparam improved
 * - interrupt verification
 * - updated documentation
 * - cleanups
 *
 * Revision 1.16  1996/06/09 00:04:56  root
 * - added configuration symbols for insmod (aha152x/aha152x1)
 *
 * Revision 1.15  1996/04/30 14:52:06  fischer
 * - proc info fixed
 * - support for extended translation for >1GB disks
 *
 * Revision 1.14  1996/01/17  15:11:20  fischer
 * - fixed lockup in MESSAGE IN phase after reconnection
 *
 * Revision 1.13  1996/01/09  02:15:53  fischer
 * - some cleanups
 * - moved request_irq behind controller initialization
 *   (to avoid spurious interrupts)
 *
 * Revision 1.12  1995/12/16  12:26:07  fischer
 * - barrier()s added
 * - configurable RESET delay added
 *
 * Revision 1.11  1995/12/06  21:18:35  fischer
 * - some minor updates
 *
 * Revision 1.10  1995/07/22  19:18:45  fischer
 * - support for 2 controllers
 * - started synchronous data transfers (not working yet)
 *
 * Revision 1.9  1995/03/18  09:20:24  root
 * - patches for PCMCIA and modules
 *
 * Revision 1.8  1995/01/21  22:07:19  root
 * - snarf_region => request_region
 * - aha152x_intr interface change
 *
 * Revision 1.7  1995/01/02  23:19:36  root
 * - updated COMMAND_SIZE to cmd_len
 * - changed sti() to restore_flags()
 * - fixed some #ifdef which generated warnings
 *
 * Revision 1.6  1994/11/24  20:35:27  root
 * - problem with odd number of bytes in fifo fixed
 *
 * Revision 1.5  1994/10/30  14:39:56  root
 * - abort code fixed
 * - debugging improved
 *
 * Revision 1.4  1994/09/12  11:33:01  root
 * - irqaction to request_irq
 * - abortion updated
 *
 * Revision 1.3  1994/08/04  13:53:05  root
 * - updates for mid-level-driver changes
 * - accept unexpected BUSFREE phase as error condition
 * - parity check now configurable
 *
 * Revision 1.2  1994/07/03  12:56:36  root
 * - cleaned up debugging code
 * - more tweaking on reset delays
 * - updated abort/reset code (pretty untested...)
 *
 * Revision 1.1  1994/05/28  21:18:49  root
 * - update for mid-level interface change (abort-reset)
 * - delays after resets adjusted for some slow devices
 *
 * Revision 1.0  1994/03/25  12:52:00  root
 * - Fixed "more data than expected" problem
 * - added new BIOS signatures
 *
 * Revision 0.102  1994/01/31  20:44:12  root
 * - minor changes in insw/outsw handling
 *
 * Revision 0.101  1993/12/13  01:16:27  root
 * - fixed STATUS phase (non-GOOD stati were dropped sometimes;
 *   fixes problems with CD-ROM sector size detection & media change)
 *
 * Revision 0.100  1993/12/10  16:58:47  root
 * - fix for unsuccessful selections in case of non-continuous id assignments
 *   on the scsi bus.
 *
 * Revision 0.99  1993/10/24  16:19:59  root
 * - fixed DATA IN (rare read errors gone)
 *
 * Revision 0.98  1993/10/17  12:54:44  root
 * - fixed some recent fixes (shame on me)
 * - moved initialization of scratch area to aha152x_queue
 *
 * Revision 0.97  1993/10/09  18:53:53  root
 * - DATA IN fixed. Rarely left data in the fifo.
 *
 * Revision 0.96  1993/10/03  00:53:59  root
 * - minor changes on DATA IN
 *
 * Revision 0.95  1993/09/24  10:36:01  root
 * - change handling of MSGI after reselection
 * - fixed sti/cli
 * - minor changes
 *
 * Revision 0.94  1993/09/18  14:08:22  root
 * - fixed bug in multiple outstanding command code
 * - changed detection
 * - support for kernel command line configuration
 * - reset corrected
 * - changed message handling
 *
 * Revision 0.93  1993/09/15  20:41:19  root
 * - fixed bugs with multiple outstanding commands
 *
 * Revision 0.92  1993/09/13  02:46:33  root
 * - multiple outstanding commands work (no problems with IBM drive)
 *
 * Revision 0.91  1993/09/12  20:51:46  root
 * added multiple outstanding commands
 * (some problem with this $%&? IBM device remain)
 *
 * Revision 0.9  1993/09/12  11:11:22  root
 * - corrected auto-configuration
 * - changed the auto-configuration (added some '#define's)
 * - added support for dis-/reconnection
 *
 * Revision 0.8  1993/09/06  23:09:39  root
 * - added support for the drive activity light
 * - minor changes
 *
 * Revision 0.7  1993/09/05  14:30:15  root
 * - improved phase detection
 * - now using the new snarf_region code of 0.99pl13
 *
 * Revision 0.6  1993/09/02  11:01:38  root
 * first public release; added some signatures and biosparam()
 *
 * Revision 0.5  1993/08/30  10:23:30  root
 * fixed timing problems with my IBM drive
 *
 * Revision 0.4  1993/08/29  14:06:52  root
 * fixed some problems with timeouts due incomplete commands
 *
 * Revision 0.3  1993/08/28  15:55:03  root
 * writing data works too.  mounted and worked on a dos partition
 *
 * Revision 0.2  1993/08/27  22:42:07  root
 * reading data works.  Mounted a msdos partition.
 *
 * Revision 0.1  1993/08/25  13:38:30  root
 * first "damn thing doesn't work" version
 *
 * Revision 0.0  1993/08/14  19:54:25  root
 * empty function bodies; detect() works.
 *
 **************************************************************************

 see Documentation/scsi/aha152x.rst for configuration details

 **************************************************************************/

#include <linux/module.h>
#include <asm/irq.h>
#include <linux/io.h>
#include <linux/blkdev.h>
#include <linux/completion.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/wait.h>
#include <linux/ioport.h>
#include <linux/delay.h>
#include <linux/proc_fs.h>
#include <linux/interrupt.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/isapnp.h>
#include <linux/spinlock.h>
#include <linux/workqueue.h>
#include <linux/list.h>
#include <linux/slab.h>

#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_dbg.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_eh.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_tcq.h>
#include <scsi/scsi_transport_spi.h>
#include <scsi/scsicam.h>
#include "aha152x.h"

static LIST_HEAD(aha152x_host_list);


/* DEFINES */

/* For PCMCIA cards, always use AUTOCONF */
#if defined(AHA152X_PCMCIA) || defined(MODULE)
#if !defined(AUTOCONF)
#define AUTOCONF
#endif
#endif

#if !defined(AUTOCONF) && !defined(SETUP0)
#error define AUTOCONF or SETUP0
#endif

#define	DO_LOCK(flags)		spin_lock_irqsave(&QLOCK,flags)
#define	DO_UNLOCK(flags)	spin_unlock_irqrestore(&QLOCK,flags)

#define LEAD		"(scsi%d:%d:%d) "
#define INFO_LEAD	KERN_INFO	LEAD
#define CMDINFO(cmd) \
			(cmd) ? ((cmd)->device->host->host_no) : -1, \
                        (cmd) ? ((cmd)->device->id & 0x0f) : -1, \
			(cmd) ? ((u8)(cmd)->device->lun & 0x07) : -1

static inline void
CMD_INC_RESID(struct scsi_cmnd *cmd, int inc)
{
	scsi_set_resid(cmd, scsi_get_resid(cmd) + inc);
}

#define DELAY_DEFAULT 1000

#if defined(AHA152X_PCMCIA)
#define IRQ_MIN 0
#define IRQ_MAX 16
#else
#define IRQ_MIN 9
#if defined(__PPC)
#define IRQ_MAX (nr_irqs-1)
#else
#define IRQ_MAX 12
#endif
#endif

enum {
	not_issued	= 0x0001,	/* command not yet issued */
	selecting	= 0x0002,	/* target is being selected */
	identified	= 0x0004,	/* IDENTIFY was sent */
	disconnected	= 0x0008,	/* target disconnected */
	completed	= 0x0010,	/* target sent COMMAND COMPLETE */
	aborted		= 0x0020,	/* ABORT was sent */
	resetted	= 0x0040,	/* BUS DEVICE RESET was sent */
	spiordy		= 0x0080,	/* waiting for SPIORDY to raise */
	syncneg		= 0x0100,	/* synchronous negotiation in progress */
	aborting	= 0x0200,	/* ABORT is pending */
	resetting	= 0x0400,	/* BUS DEVICE RESET is pending */
	check_condition = 0x0800,	/* requesting sense after CHECK CONDITION */
};

struct aha152x_cmd_priv {
	char *ptr;
	int this_residual;
	struct scatterlist *buffer;
	int status;
	int message;
	int sent_command;
	int phase;
};

static struct aha152x_cmd_priv *aha152x_priv(struct scsi_cmnd *cmd)
{
	return scsi_cmd_priv(cmd);
}

MODULE_AUTHOR("Jürgen Fischer");
MODULE_DESCRIPTION(AHA152X_REVID);
MODULE_LICENSE("GPL");

#if !defined(AHA152X_PCMCIA)
#if defined(MODULE)
static int io[] = {0, 0};
module_param_hw_array(io, int, ioport, NULL, 0);
MODULE_PARM_DESC(io,"base io address of controller");

static int irq[] = {0, 0};
module_param_hw_array(irq, int, irq, NULL, 0);
MODULE_PARM_DESC(irq,"interrupt for controller");

static int scsiid[] = {7, 7};
module_param_array(scsiid, int, NULL, 0);
MODULE_PARM_DESC(scsiid,"scsi id of controller");

static int reconnect[] = {1, 1};
module_param_array(reconnect, int, NULL, 0);
MODULE_PARM_DESC(reconnect,"allow targets to disconnect");

static int parity[] = {1, 1};
module_param_array(parity, int, NULL, 0);
MODULE_PARM_DESC(parity,"use scsi parity");

static int sync[] = {1, 1};
module_param_array(sync, int, NULL, 0);
MODULE_PARM_DESC(sync,"use synchronous transfers");

static int delay[] = {DELAY_DEFAULT, DELAY_DEFAULT};
module_param_array(delay, int, NULL, 0);
MODULE_PARM_DESC(delay,"scsi reset delay");

static int exttrans[] = {0, 0};
module_param_array(exttrans, int, NULL, 0);
MODULE_PARM_DESC(exttrans,"use extended translation");

static int aha152x[] = {0, 11, 7, 1, 1, 0, DELAY_DEFAULT, 0};
module_param_array(aha152x, int, NULL, 0);
MODULE_PARM_DESC(aha152x, "parameters for first controller");

static int aha152x1[] = {0, 11, 7, 1, 1, 0, DELAY_DEFAULT, 0};
module_param_array(aha152x1, int, NULL, 0);
MODULE_PARM_DESC(aha152x1, "parameters for second controller");
#endif /* MODULE */

#ifdef __ISAPNP__
static struct isapnp_device_id id_table[] = {
	{ ISAPNP_ANY_ID, ISAPNP_ANY_ID,	ISAPNP_VENDOR('A', 'D', 'P'), ISAPNP_FUNCTION(0x1502), 0 },
	{ ISAPNP_ANY_ID, ISAPNP_ANY_ID,	ISAPNP_VENDOR('A', 'D', 'P'), ISAPNP_FUNCTION(0x1505), 0 },
	{ ISAPNP_ANY_ID, ISAPNP_ANY_ID,	ISAPNP_VENDOR('A', 'D', 'P'), ISAPNP_FUNCTION(0x1510), 0 },
	{ ISAPNP_ANY_ID, ISAPNP_ANY_ID,	ISAPNP_VENDOR('A', 'D', 'P'), ISAPNP_FUNCTION(0x1515), 0 },
	{ ISAPNP_ANY_ID, ISAPNP_ANY_ID,	ISAPNP_VENDOR('A', 'D', 'P'), ISAPNP_FUNCTION(0x1520), 0 },
	{ ISAPNP_ANY_ID, ISAPNP_ANY_ID,	ISAPNP_VENDOR('A', 'D', 'P'), ISAPNP_FUNCTION(0x2015), 0 },
	{ ISAPNP_ANY_ID, ISAPNP_ANY_ID,	ISAPNP_VENDOR('A', 'D', 'P'), ISAPNP_FUNCTION(0x1522), 0 },
	{ ISAPNP_ANY_ID, ISAPNP_ANY_ID,	ISAPNP_VENDOR('A', 'D', 'P'), ISAPNP_FUNCTION(0x2215), 0 },
	{ ISAPNP_ANY_ID, ISAPNP_ANY_ID,	ISAPNP_VENDOR('A', 'D', 'P'), ISAPNP_FUNCTION(0x1530), 0 },
	{ ISAPNP_ANY_ID, ISAPNP_ANY_ID,	ISAPNP_VENDOR('A', 'D', 'P'), ISAPNP_FUNCTION(0x3015), 0 },
	{ ISAPNP_ANY_ID, ISAPNP_ANY_ID,	ISAPNP_VENDOR('A', 'D', 'P'), ISAPNP_FUNCTION(0x1532), 0 },
	{ ISAPNP_ANY_ID, ISAPNP_ANY_ID,	ISAPNP_VENDOR('A', 'D', 'P'), ISAPNP_FUNCTION(0x3215), 0 },
	{ ISAPNP_ANY_ID, ISAPNP_ANY_ID,	ISAPNP_VENDOR('A', 'D', 'P'), ISAPNP_FUNCTION(0x6360), 0 },
	{ ISAPNP_DEVICE_SINGLE_END, }
};
MODULE_DEVICE_TABLE(isapnp, id_table);
#endif /* ISAPNP */

#endif /* !AHA152X_PCMCIA */

static const struct scsi_host_template aha152x_driver_template;

/*
 * internal states of the host
 *
 */
enum aha152x_state {
	idle=0,
	unknown,
	seldo,
	seldi,
	selto,
	busfree,
	msgo,
	cmd,
	msgi,
	status,
	datai,
	datao,
	parerr,
	rsti,
	maxstate
};

/*
 * current state information of the host
 *
 */
struct aha152x_hostdata {
	struct scsi_cmnd *issue_SC;
		/* pending commands to issue */

	struct scsi_cmnd *current_SC;
		/* current command on the bus */

	struct scsi_cmnd *disconnected_SC;
		/* commands that disconnected */

	struct scsi_cmnd *done_SC;
		/* command that was completed */

	spinlock_t lock;
		/* host lock */

#if defined(AHA152X_STAT)
	int	      total_commands;
	int	      disconnections;
	int	      busfree_without_any_action;
	int	      busfree_without_old_command;
	int	      busfree_without_new_command;
	int	      busfree_without_done_command;
	int	      busfree_with_check_condition;
	int	      count[maxstate];
	int	      count_trans[maxstate];
	unsigned long time[maxstate];
#endif

	int commands;		/* current number of commands */

	int reconnect;		/* disconnection allowed */
	int parity;		/* parity checking enabled */
	int synchronous;	/* synchronous transferes enabled */
	int delay;		/* reset out delay */
	int ext_trans;		/* extended translation enabled */

	int swint;		/* software-interrupt was fired during detect() */
	int service;		/* bh needs to be run */
	int in_intr;		/* bh is running */

	/* current state,
	   previous state,
	   last state different from current state */
	enum aha152x_state state, prevstate, laststate;

	int target;
		/* reconnecting target */

	unsigned char syncrate[8];
		/* current synchronous transfer agreements */

	unsigned char syncneg[8];
		/* 0: no negotiation;
		 * 1: negotiation in progress;
		 * 2: negotiation completed
		 */

	int cmd_i;
		/* number of sent bytes of current command */

	int msgi_len;
		/* number of received message bytes */
	unsigned char msgi[256];
		/* received message bytes */

	int msgo_i, msgo_len;
		/* number of sent bytes and length of current messages */
	unsigned char msgo[256];
		/* pending messages */

	int data_len;
		/* number of sent/received bytes in dataphase */

	unsigned long io_port0;
	unsigned long io_port1;

#ifdef __ISAPNP__
	struct pnp_dev *pnpdev;
#endif
	struct list_head host_list;
};


/*
 * host specific command extension
 *
 */
struct aha152x_scdata {
	struct scsi_cmnd *next;	/* next sc in queue */
	struct completion *done;/* semaphore to block on */
	struct scsi_eh_save ses;
};

/* access macros for hostdata */

#define HOSTDATA(shpnt)		((struct aha152x_hostdata *) &shpnt->hostdata)

#define HOSTNO			((shpnt)->host_no)

#define CURRENT_SC		(HOSTDATA(shpnt)->current_SC)
#define DONE_SC			(HOSTDATA(shpnt)->done_SC)
#define ISSUE_SC		(HOSTDATA(shpnt)->issue_SC)
#define DISCONNECTED_SC		(HOSTDATA(shpnt)->disconnected_SC)
#define QLOCK			(HOSTDATA(shpnt)->lock)
#define QLOCKER			(HOSTDATA(shpnt)->locker)
#define QLOCKERL		(HOSTDATA(shpnt)->lockerl)

#define STATE			(HOSTDATA(shpnt)->state)
#define PREVSTATE		(HOSTDATA(shpnt)->prevstate)
#define LASTSTATE		(HOSTDATA(shpnt)->laststate)

#define RECONN_TARGET		(HOSTDATA(shpnt)->target)

#define CMD_I			(HOSTDATA(shpnt)->cmd_i)

#define MSGO(i)			(HOSTDATA(shpnt)->msgo[i])
#define MSGO_I			(HOSTDATA(shpnt)->msgo_i)
#define MSGOLEN			(HOSTDATA(shpnt)->msgo_len)
#define ADDMSGO(x)		(MSGOLEN<256 ? (void)(MSGO(MSGOLEN++)=x) : aha152x_error(shpnt,"MSGO overflow"))

#define MSGI(i)			(HOSTDATA(shpnt)->msgi[i])
#define MSGILEN			(HOSTDATA(shpnt)->msgi_len)
#define ADDMSGI(x)		(MSGILEN<256 ? (void)(MSGI(MSGILEN++)=x) : aha152x_error(shpnt,"MSGI overflow"))

#define DATA_LEN		(HOSTDATA(shpnt)->data_len)

#define SYNCRATE		(HOSTDATA(shpnt)->syncrate[CURRENT_SC->device->id])
#define SYNCNEG			(HOSTDATA(shpnt)->syncneg[CURRENT_SC->device->id])

#define DELAY			(HOSTDATA(shpnt)->delay)
#define EXT_TRANS		(HOSTDATA(shpnt)->ext_trans)
#define TC1550			(HOSTDATA(shpnt)->tc1550)
#define RECONNECT		(HOSTDATA(shpnt)->reconnect)
#define PARITY			(HOSTDATA(shpnt)->parity)
#define SYNCHRONOUS		(HOSTDATA(shpnt)->synchronous)

#define HOSTIOPORT0		(HOSTDATA(shpnt)->io_port0)
#define HOSTIOPORT1		(HOSTDATA(shpnt)->io_port1)

#define SCDATA(SCpnt)		((struct aha152x_scdata *) (SCpnt)->host_scribble)
#define SCNEXT(SCpnt)		SCDATA(SCpnt)->next
#define SCSEM(SCpnt)		SCDATA(SCpnt)->done

#define SG_ADDRESS(buffer)	((char *) sg_virt((buffer)))

/* state handling */
static void seldi_run(struct Scsi_Host *shpnt);
static void seldo_run(struct Scsi_Host *shpnt);
static void selto_run(struct Scsi_Host *shpnt);
static void busfree_run(struct Scsi_Host *shpnt);

static void msgo_init(struct Scsi_Host *shpnt);
static void msgo_run(struct Scsi_Host *shpnt);
static void msgo_end(struct Scsi_Host *shpnt);

static void cmd_init(struct Scsi_Host *shpnt);
static void cmd_run(struct Scsi_Host *shpnt);
static void cmd_end(struct Scsi_Host *shpnt);

static void datai_init(struct Scsi_Host *shpnt);
static void datai_run(struct Scsi_Host *shpnt);
static void datai_end(struct Scsi_Host *shpnt);

static void datao_init(struct Scsi_Host *shpnt);
static void datao_run(struct Scsi_Host *shpnt);
static void datao_end(struct Scsi_Host *shpnt);

static void status_run(struct Scsi_Host *shpnt);

static void msgi_run(struct Scsi_Host *shpnt);
static void msgi_end(struct Scsi_Host *shpnt);

static void parerr_run(struct Scsi_Host *shpnt);
static void rsti_run(struct Scsi_Host *shpnt);

static void is_complete(struct Scsi_Host *shpnt);

/*
 * driver states
 *
 */
static struct {
	char		*name;
	void		(*init)(struct Scsi_Host *);
	void		(*run)(struct Scsi_Host *);
	void		(*end)(struct Scsi_Host *);
	int		spio;
} states[] = {
	{ "idle",	NULL,		NULL,		NULL,		0},
	{ "unknown",	NULL,		NULL,		NULL,		0},
	{ "seldo",	NULL,		seldo_run,	NULL,		0},
	{ "seldi",	NULL,		seldi_run,	NULL,		0},
	{ "selto",	NULL,		selto_run,	NULL,		0},
	{ "busfree",	NULL,		busfree_run,	NULL,		0},
	{ "msgo",	msgo_init,	msgo_run,	msgo_end,	1},
	{ "cmd",	cmd_init,	cmd_run,	cmd_end,	1},
	{ "msgi",	NULL,		msgi_run,	msgi_end,	1},
	{ "status",	NULL,		status_run,	NULL,		1},
	{ "datai",	datai_init,	datai_run,	datai_end,	0},
	{ "datao",	datao_init,	datao_run,	datao_end,	0},
	{ "parerr",	NULL,		parerr_run,	NULL,		0},
	{ "rsti",	NULL,		rsti_run,	NULL,		0},
};

/* setup & interrupt */
static irqreturn_t intr(int irq, void *dev_id);
static void reset_ports(struct Scsi_Host *shpnt);
static void aha152x_error(struct Scsi_Host *shpnt, char *msg);
static void done(struct Scsi_Host *shpnt, unsigned char status_byte,
		 unsigned char host_byte);

/* diagnostics */
static void show_command(struct scsi_cmnd * ptr);
static void show_queues(struct Scsi_Host *shpnt);
static void disp_enintr(struct Scsi_Host *shpnt);


/*
 *  queue services:
 *
 */
static inline void append_SC(struct scsi_cmnd **SC, struct scsi_cmnd *new_SC)
{
	struct scsi_cmnd *end;

	SCNEXT(new_SC) = NULL;
	if (!*SC)
		*SC = new_SC;
	else {
		for (end = *SC; SCNEXT(end); end = SCNEXT(end))
			;
		SCNEXT(end) = new_SC;
	}
}

static inline struct scsi_cmnd *remove_first_SC(struct scsi_cmnd ** SC)
{
	struct scsi_cmnd *ptr;

	ptr = *SC;
	if (ptr) {
		*SC = SCNEXT(*SC);
		SCNEXT(ptr)=NULL;
	}
	return ptr;
}

static inline struct scsi_cmnd *remove_lun_SC(struct scsi_cmnd ** SC,
					      int target, int lun)
{
	struct scsi_cmnd *ptr, *prev;

	for (ptr = *SC, prev = NULL;
	     ptr && ((ptr->device->id != target) || (ptr->device->lun != lun));
	     prev = ptr, ptr = SCNEXT(ptr))
	     ;

	if (ptr) {
		if (prev)
			SCNEXT(prev) = SCNEXT(ptr);
		else
			*SC = SCNEXT(ptr);

		SCNEXT(ptr)=NULL;
	}

	return ptr;
}

static inline struct scsi_cmnd *remove_SC(struct scsi_cmnd **SC,
					  struct scsi_cmnd *SCp)
{
	struct scsi_cmnd *ptr, *prev;

	for (ptr = *SC, prev = NULL;
	     ptr && SCp!=ptr;
	     prev = ptr, ptr = SCNEXT(ptr))
	     ;

	if (ptr) {
		if (prev)
			SCNEXT(prev) = SCNEXT(ptr);
		else
			*SC = SCNEXT(ptr);

		SCNEXT(ptr)=NULL;
	}

	return ptr;
}

static irqreturn_t swintr(int irqno, void *dev_id)
{
	struct Scsi_Host *shpnt = dev_id;

	HOSTDATA(shpnt)->swint++;

	SETPORT(DMACNTRL0, INTEN);
	return IRQ_HANDLED;
}

struct Scsi_Host *aha152x_probe_one(struct aha152x_setup *setup)
{
	struct Scsi_Host *shpnt;

	shpnt = scsi_host_alloc(&aha152x_driver_template, sizeof(struct aha152x_hostdata));
	if (!shpnt) {
		printk(KERN_ERR "aha152x: scsi_host_alloc failed\n");
		return NULL;
	}

	memset(HOSTDATA(shpnt), 0, sizeof *HOSTDATA(shpnt));
	INIT_LIST_HEAD(&HOSTDATA(shpnt)->host_list);

	/* need to have host registered before triggering any interrupt */
	list_add_tail(&HOSTDATA(shpnt)->host_list, &aha152x_host_list);

	shpnt->io_port   = setup->io_port;
	shpnt->n_io_port = IO_RANGE;
	shpnt->irq       = setup->irq;

	if (!setup->tc1550) {
		HOSTIOPORT0 = setup->io_port;
		HOSTIOPORT1 = setup->io_port;
	} else {
		HOSTIOPORT0 = setup->io_port+0x10;
		HOSTIOPORT1 = setup->io_port-0x10;
	}

	spin_lock_init(&QLOCK);
	RECONNECT   = setup->reconnect;
	SYNCHRONOUS = setup->synchronous;
	PARITY      = setup->parity;
	DELAY       = setup->delay;
	EXT_TRANS   = setup->ext_trans;

	SETPORT(SCSIID, setup->scsiid << 4);
	shpnt->this_id = setup->scsiid;

	if (setup->reconnect)
		shpnt->can_queue = AHA152X_MAXQUEUE;

	/* RESET OUT */
	printk("aha152x: resetting bus...\n");
	SETPORT(SCSISEQ, SCSIRSTO);
	mdelay(256);
	SETPORT(SCSISEQ, 0);
	mdelay(DELAY);

	reset_ports(shpnt);

	printk(KERN_INFO
	       "aha152x%d%s: "
	       "vital data: rev=%x, "
	       "io=0x%03lx (0x%03lx/0x%03lx), "
	       "irq=%d, "
	       "scsiid=%d, "
	       "reconnect=%s, "
	       "parity=%s, "
	       "synchronous=%s, "
	       "delay=%d, "
	       "extended translation=%s\n",
	       shpnt->host_no, setup->tc1550 ? " (tc1550 mode)" : "",
	       GETPORT(REV) & 0x7,
	       shpnt->io_port, HOSTIOPORT0, HOSTIOPORT1,
	       shpnt->irq,
	       shpnt->this_id,
	       RECONNECT ? "enabled" : "disabled",
	       PARITY ? "enabled" : "disabled",
	       SYNCHRONOUS ? "enabled" : "disabled",
	       DELAY,
	       EXT_TRANS ? "enabled" : "disabled");

	/* not expecting any interrupts */
	SETPORT(SIMODE0, 0);
	SETPORT(SIMODE1, 0);

	if (request_irq(shpnt->irq, swintr, IRQF_SHARED, "aha152x", shpnt)) {
		printk(KERN_ERR "aha152x%d: irq %d busy.\n", shpnt->host_no, shpnt->irq);
		goto out_host_put;
	}

	HOSTDATA(shpnt)->swint = 0;

	printk(KERN_INFO "aha152x%d: trying software interrupt, ", shpnt->host_no);

	mb();
	SETPORT(DMACNTRL0, SWINT|INTEN);
	mdelay(1000);
	free_irq(shpnt->irq, shpnt);

	if (!HOSTDATA(shpnt)->swint) {
		if (TESTHI(DMASTAT, INTSTAT)) {
			printk("lost.\n");
		} else {
			printk("failed.\n");
		}

		SETPORT(DMACNTRL0, INTEN);

		printk(KERN_ERR "aha152x%d: irq %d possibly wrong.  "
				"Please verify.\n", shpnt->host_no, shpnt->irq);
		goto out_host_put;
	}
	printk("ok.\n");


	/* clear interrupts */
	SETPORT(SSTAT0, 0x7f);
	SETPORT(SSTAT1, 0xef);

	if (request_irq(shpnt->irq, intr, IRQF_SHARED, "aha152x", shpnt)) {
		printk(KERN_ERR "aha152x%d: failed to reassign irq %d.\n", shpnt->host_no, shpnt->irq);
		goto out_host_put;
	}

	if( scsi_add_host(shpnt, NULL) ) {
		free_irq(shpnt->irq, shpnt);
		printk(KERN_ERR "aha152x%d: failed to add host.\n", shpnt->host_no);
		goto out_host_put;
	}

	scsi_scan_host(shpnt);

	return shpnt;

out_host_put:
	list_del(&HOSTDATA(shpnt)->host_list);
	scsi_host_put(shpnt);

	return NULL;
}

void aha152x_release(struct Scsi_Host *shpnt)
{
	if (!shpnt)
		return;

	scsi_remove_host(shpnt);
	if (shpnt->irq)
		free_irq(shpnt->irq, shpnt);

#if !defined(AHA152X_PCMCIA)
	if (shpnt->io_port)
		release_region(shpnt->io_port, IO_RANGE);
#endif

#ifdef __ISAPNP__
	if (HOSTDATA(shpnt)->pnpdev)
		pnp_device_detach(HOSTDATA(shpnt)->pnpdev);
#endif

	list_del(&HOSTDATA(shpnt)->host_list);
	scsi_host_put(shpnt);
}


/*
 * setup controller to generate interrupts depending
 * on current state (lock has to be acquired)
 *
 */
static int setup_expected_interrupts(struct Scsi_Host *shpnt)
{
	if(CURRENT_SC) {
		struct aha152x_cmd_priv *acp = aha152x_priv(CURRENT_SC);

		acp->phase |= 1 << 16;

		if (acp->phase & selecting) {
			SETPORT(SSTAT1, SELTO);
			SETPORT(SIMODE0, ENSELDO | (DISCONNECTED_SC ? ENSELDI : 0));
			SETPORT(SIMODE1, ENSELTIMO);
		} else {
			SETPORT(SIMODE0, (acp->phase & spiordy) ? ENSPIORDY : 0);
			SETPORT(SIMODE1, ENPHASEMIS | ENSCSIRST | ENSCSIPERR | ENBUSFREE);
		}
	} else if(STATE==seldi) {
		SETPORT(SIMODE0, 0);
		SETPORT(SIMODE1, ENPHASEMIS | ENSCSIRST | ENSCSIPERR | ENBUSFREE);
	} else {
		SETPORT(SIMODE0, DISCONNECTED_SC ? ENSELDI : 0);
		SETPORT(SIMODE1, ENSCSIRST | ( (ISSUE_SC||DONE_SC) ? ENBUSFREE : 0));
	}

	if(!HOSTDATA(shpnt)->in_intr)
		SETBITS(DMACNTRL0, INTEN);

	return TESTHI(DMASTAT, INTSTAT);
}


/*
 *  Queue a command and setup interrupts for a free bus.
 */
static int aha152x_internal_queue(struct scsi_cmnd *SCpnt,
				  struct completion *complete, int phase)
{
	struct aha152x_cmd_priv *acp = aha152x_priv(SCpnt);
	struct Scsi_Host *shpnt = SCpnt->device->host;
	unsigned long flags;

	acp->phase        = not_issued | phase;
	acp->status       = 0x1; /* Illegal status by SCSI standard */
	acp->message      = 0;
	acp->sent_command = 0;

	if (acp->phase & (resetting | check_condition)) {
		if (!SCpnt->host_scribble || SCSEM(SCpnt) || SCNEXT(SCpnt)) {
			scmd_printk(KERN_ERR, SCpnt, "cannot reuse command\n");
			return FAILED;
		}
	} else {
		SCpnt->host_scribble = kmalloc(sizeof(struct aha152x_scdata), GFP_ATOMIC);
		if(!SCpnt->host_scribble) {
			scmd_printk(KERN_ERR, SCpnt, "allocation failed\n");
			return FAILED;
		}
	}

	SCNEXT(SCpnt)		= NULL;
	SCSEM(SCpnt)		= complete;

	/* setup scratch area
	   SCp.ptr              : buffer pointer
	   SCp.this_residual    : buffer length
	   SCp.buffer           : next buffer
	   SCp.phase            : current state of the command */

	if ((phase & resetting) || !scsi_sglist(SCpnt)) {
		acp->ptr           = NULL;
		acp->this_residual = 0;
		scsi_set_resid(SCpnt, 0);
		acp->buffer        = NULL;
	} else {
		scsi_set_resid(SCpnt, scsi_bufflen(SCpnt));
		acp->buffer        = scsi_sglist(SCpnt);
		acp->ptr           = SG_ADDRESS(acp->buffer);
		acp->this_residual = acp->buffer->length;
	}

	DO_LOCK(flags);

#if defined(AHA152X_STAT)
	HOSTDATA(shpnt)->total_commands++;
#endif

	/* Turn led on, when this is the first command. */
	HOSTDATA(shpnt)->commands++;
	if (HOSTDATA(shpnt)->commands==1)
		SETPORT(PORTA, 1);

	append_SC(&ISSUE_SC, SCpnt);

	if(!HOSTDATA(shpnt)->in_intr)
		setup_expected_interrupts(shpnt);

	DO_UNLOCK(flags);

	return 0;
}

/*
 *  queue a command
 *
 */
static int aha152x_queue_lck(struct scsi_cmnd *SCpnt)
{
	return aha152x_internal_queue(SCpnt, NULL, 0);
}

static DEF_SCSI_QCMD(aha152x_queue)


/*
 *
 */
static void reset_done(struct scsi_cmnd *SCpnt)
{
	if(SCSEM(SCpnt)) {
		complete(SCSEM(SCpnt));
	} else {
		printk(KERN_ERR "aha152x: reset_done w/o completion\n");
	}
}

static void aha152x_scsi_done(struct scsi_cmnd *SCpnt)
{
	if (aha152x_priv(SCpnt)->phase & resetting)
		reset_done(SCpnt);
	else
		scsi_done(SCpnt);
}

/*
 *  Abort a command
 *
 */
static int aha152x_abort(struct scsi_cmnd *SCpnt)
{
	struct Scsi_Host *shpnt = SCpnt->device->host;
	struct scsi_cmnd *ptr;
	unsigned long flags;

	DO_LOCK(flags);

	ptr=remove_SC(&ISSUE_SC, SCpnt);

	if(ptr) {
		HOSTDATA(shpnt)->commands--;
		if (!HOSTDATA(shpnt)->commands)
			SETPORT(PORTA, 0);
		DO_UNLOCK(flags);

		kfree(SCpnt->host_scribble);
		SCpnt->host_scribble=NULL;

		return SUCCESS;
	}

	DO_UNLOCK(flags);

	/*
	 * FIXME:
	 * for current command: queue ABORT for message out and raise ATN
	 * for disconnected command: pseudo SC with ABORT message or ABORT on reselection?
	 *
	 */

	scmd_printk(KERN_ERR, SCpnt,
		    "cannot abort running or disconnected command\n");

	return FAILED;
}

/*
 * Reset a device
 *
 */
static int aha152x_device_reset(struct scsi_cmnd * SCpnt)
{
	struct Scsi_Host *shpnt = SCpnt->device->host;
	DECLARE_COMPLETION(done);
	int ret, issued, disconnected;
	unsigned char old_cmd_len = SCpnt->cmd_len;
	unsigned long flags;
	unsigned long timeleft;

	if(CURRENT_SC==SCpnt) {
		scmd_printk(KERN_ERR, SCpnt, "cannot reset current device\n");
		return FAILED;
	}

	DO_LOCK(flags);
	issued       = remove_SC(&ISSUE_SC, SCpnt) == NULL;
	disconnected = issued && remove_SC(&DISCONNECTED_SC, SCpnt);
	DO_UNLOCK(flags);

	SCpnt->cmd_len         = 0;

	aha152x_internal_queue(SCpnt, &done, resetting);

	timeleft = wait_for_completion_timeout(&done, 100*HZ);
	if (!timeleft) {
		/* remove command from issue queue */
		DO_LOCK(flags);
		remove_SC(&ISSUE_SC, SCpnt);
		DO_UNLOCK(flags);
	}

	SCpnt->cmd_len         = old_cmd_len;

	DO_LOCK(flags);

	if (aha152x_priv(SCpnt)->phase & resetted) {
		HOSTDATA(shpnt)->commands--;
		if (!HOSTDATA(shpnt)->commands)
			SETPORT(PORTA, 0);
		kfree(SCpnt->host_scribble);
		SCpnt->host_scribble=NULL;

		ret = SUCCESS;
	} else {
		/* requeue */
		if(!issued) {
			append_SC(&ISSUE_SC, SCpnt);
		} else if(disconnected) {
			append_SC(&DISCONNECTED_SC, SCpnt);
		}

		ret = FAILED;
	}

	DO_UNLOCK(flags);
	return ret;
}

static void free_hard_reset_SCs(struct Scsi_Host *shpnt,
				struct scsi_cmnd **SCs)
{
	struct scsi_cmnd *ptr;

	ptr=*SCs;
	while(ptr) {
		struct scsi_cmnd *next;

		if(SCDATA(ptr)) {
			next = SCNEXT(ptr);
		} else {
			scmd_printk(KERN_DEBUG, ptr,
				    "queue corrupted at %p\n", ptr);
			next = NULL;
		}

		if (!ptr->device->soft_reset) {
			remove_SC(SCs, ptr);
			HOSTDATA(shpnt)->commands--;
			kfree(ptr->host_scribble);
			ptr->host_scribble=NULL;
		}

		ptr = next;
	}
}

/*
 * Reset the bus
 *
 * AIC-6260 has a hard reset (MRST signal), but apparently
 * one cannot trigger it via software. So live with
 * a soft reset; no-one seemed to have cared.
 */