acornscsi.c.2

arm平台上的uclinux系统全部源代码

/*
 * linux/arch/arm/drivers/scsi/acornscsi.c
 *
 *  Acorn SCSI 3 driver
 *  By R.M.King.
 *
 * Abandoned using the Select and Transfer command since there were
 * some nasty races between our software and the target devices that
 * were not easy to solve, and the device errata had a lot of entries
 * for this command, some of them quite nasty...
 *
 * Changelog:
 *  26-Sep-1997	RMK	Re-jigged to use the queue module.
 *			Re-coded state machine to be based on driver
 *			state not scsi state.  Should be easier to debug.
 *			Added acornscsi_release to clean up properly.
 *			Updated proc/scsi reporting.
 *  05-Oct-1997	RMK	Implemented writing to SCSI devices.
 *  06-Oct-1997	RMK	Corrected small (non-serious) bug with the connect/
 *			reconnect race condition causing a warning message.
 */
#define DEBUG_NO_WRITE	1
#define DEBUG_QUEUES	2
#define DEBUG_DMA	4
#define DEBUG_ABORT	8
#define DEBUG_DISCON	16
#define DEBUG_CONNECT	32
#define DEBUG_PHASES	64
#define DEBUG_WRITE	128
#define DEBUG_LINK	256
#define DEBUG_MESSAGES	512
#define DEBUG_RESET	1024
#define DEBUG_ALL	(DEBUG_RESET|DEBUG_MESSAGES|DEBUG_LINK|DEBUG_WRITE|\
			 DEBUG_PHASES|DEBUG_CONNECT|DEBUG_DISCON|DEBUG_ABORT|\
			 DEBUG_DMA|DEBUG_QUEUES|DEBUG_NO_WRITE)

/* DRIVER CONFIGURATION
 *
 * SCSI-II Tagged queue support.
 *
 * I don't have any SCSI devices that support it, so it is totally untested
 * (except to make sure that it doesn't interfere with any non-tagging
 * devices).  It is not fully implemented either - what happens when a
 * tagging device reconnects???
 *
 * You can tell if you have a device that supports tagged queueing my
 * cating (eg) /proc/scsi/acornscsi/0 and see if the SCSI revision is reported
 * as '2 TAG'.
 */
#define SCSI2_TAG
/*
 * SCSI-II Linked command support.
 *
 * The higher level code doesn't support linked commands yet.
 */
#undef SCSI2_LINK
/*
 * SCSI-II Synchronous transfer support.
 *
 * Tried and tested...
 *
 * SDTR_SIZE	  - maximum number of un-acknowledged bytes (0 = off, 12 = max)
 * SDTR_PERIOD	  - period of REQ signal (min=125, max=1020)
 * DEFAULT_PERIOD - default REQ period.
 */
#define SCSI2_SYNC
#define SDTR_SIZE	12
#define SDTR_PERIOD	125
#define DEFAULT_PERIOD	500

/*
 * Debugging information
 *
 * DEBUG	  - bit mask from list above
 * DEBUG_TARGET   - is defined to the target number if you want to debug
 *		    a specific target. [only recon/write/dma].
 */
#define DEBUG (DEBUG_RESET|DEBUG_WRITE|DEBUG_NO_WRITE)
/* only allow writing to SCSI device 0 */
#define NO_WRITE 0xFE

/*#define DEBUG_TARGET 2*/
/*
 * Select timeout time (in 10ms units)
 *
 * This is the timeout used between the start of selection and the WD33C93
 * chip deciding that the device isn't responding.
 */
#define TIMEOUT_TIME 10
/*
 * Define this if you want to have verbose explaination of SCSI
 * status/messages.
 */
#undef CONFIG_ACORNSCSI_CONSTANTS
/*
 * Define this if you want to use the on board DMAC
 */
#define USE_DMAC
/*
 * List of devices that the driver will recognise
 */
#define ACORNSCSI_LIST { MANU_ACORN, PROD_ACORN_SCSI }
/*
 * ====================================================================================
 */

#ifdef DEBUG_TARGET
#define DBG(cmd,xxx...) \
  if (cmd->target == DEBUG_TARGET) { \
    xxx; \
  }
#else
#define DBG(cmd,xxx...) xxx
#endif

#ifndef STRINGIFY
#define STRINGIFY(x) #x
#endif
#define STR(x) STRINGIFY(x)
#define NO_WRITE_STR STR(NO_WRITE)

#include <linux/config.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/string.h>
#include <linux/signal.h>
#include <linux/errno.h>
#include <linux/proc_fs.h>
#include <linux/stat.h>
#include <linux/ioport.h>
#include <asm/bitops.h>
#include <asm/delay.h>
#include <asm/system.h>
#include <asm/io.h>
#include <asm/ecard.h>

#include "../block/blk.h"
#include "scsi.h"
#include "hosts.h"
#include "acornscsi.h"
#include "constants.h"

#define VER_MAJOR 2
#define VER_MINOR 0
#define VER_PATCH 3

#ifndef ABORT_TAG
#define ABORT_TAG 0xd
#else
#error "Yippee!  ABORT TAG is now defined!  Remove this error!"
#endif

#ifndef NO_IRQ
#define NO_IRQ 255
#endif

/*
 * DMAC setup parameters
 */ 
#define INIT_DEVCON0	(DEVCON0_RQL|DEVCON0_EXW|DEVCON0_CMP)
#define INIT_DEVCON1	(DEVCON1_BHLD)
#define DMAC_READ	(MODECON_READ)
#define DMAC_WRITE	(MODECON_WRITE)
#define INIT_SBICDMA	(CTRL_DMABURST)

#ifdef SCSI2_LINK
#error SCSI2 LINKed commands not supported (yet)!
#endif

/*
 * Size of on-board DMA buffer
 */
#define DMAC_BUFFER_SIZE	65536

/*
 * This is used to dump the previous states of the SBIC
 */
static struct status_entry {
	unsigned long	when;
	unsigned char	ssr;
	unsigned char	ph;
	unsigned char	irq;
	unsigned char	unused;
} status[9][16];
static unsigned char status_ptr[9];

#define ADD_STATUS(_q,_ssr,_ph,_irq) \
({							\
	status[(_q)][status_ptr[(_q)]].when = jiffies;	\
	status[(_q)][status_ptr[(_q)]].ssr  = (_ssr);	\
	status[(_q)][status_ptr[(_q)]].ph   = (_ph);	\
	status[(_q)][status_ptr[(_q)]].irq  = (_irq);	\
	status_ptr[(_q)] = (status_ptr[(_q)] + 1) & 15;	\
})

unsigned int sdtr_period = SDTR_PERIOD;
unsigned int sdtr_size   = SDTR_SIZE;

static struct proc_dir_entry proc_scsi_acornscsi = {
	PROC_SCSI_EATA, 9, "acornscsi", S_IFDIR | S_IRUGO | S_IXUGO, 2
};

static void acornscsi_done (AS_Host *host, Scsi_Cmnd **SCpntp, unsigned int result);
static int acornscsi_reconnect_finish (AS_Host *host);
static void acornscsi_dma_cleanup (AS_Host *host);
static void acornscsi_abortcmd (AS_Host *host, unsigned char tag);

/* ====================================================================================
 * Miscellaneous
 */

static inline void
sbic_arm_write (unsigned int io_port, int reg, int value)
{
    arm_outb (reg, io_port);
    arm_outb (value, io_port + 4);
}

#define sbic_arm_writenext(io,val) \
	arm_outb ((val), (io) + 4)

static inline
int sbic_arm_read (unsigned int io_port, int reg)
{
    if(reg == ASR)
	   return arm_inl(io_port) & 255;
    arm_outb(reg, io_port);
    return arm_inl(io_port + 4) & 255;
}

#define sbic_arm_readnext(io) \
	arm_inb((io) + 4)

#define dmac_read(io_port,reg) \
	inb ((io_port) + (reg))

#define dmac_write(io_port,reg,value) \
	({ outb ((value), (io_port) + (reg)); })

#define dmac_clearintr(io_port) \
	({ outb (0, (io_port)); })

static inline
unsigned int dmac_address (unsigned int io_port)
{
    return dmac_read (io_port, TXADRHI) << 16 |
	   dmac_read (io_port, TXADRMD) << 8 |
	   dmac_read (io_port, TXADRLO);
}

static
unsigned long acornscsi_sbic_xfcount (AS_Host *host)
{
    unsigned long length;

    length = sbic_arm_read (host->scsi.io_port, TRANSCNTH) << 16;
    length |= sbic_arm_readnext (host->scsi.io_port) << 8;
    length |= sbic_arm_readnext (host->scsi.io_port);

    return length;
}

static void
acornscsi_csdelay (unsigned int cs)
{
    unsigned long target_jiffies, flags;

    target_jiffies = jiffies + 1 + cs * HZ / 100;

    save_flags (flags);
    sti ();

    while (jiffies < target_jiffies) barrier();

    restore_flags (flags);
}

static
void acornscsi_resetcard (AS_Host *host)
{
    unsigned int i;

    /* assert reset line */
    host->card.page_reg = 0x80;
    outb (host->card.page_reg, host->card.io_page);

    /* wait 3 cs.  SCSI standard says 25ms. */
    acornscsi_csdelay (3);

    host->card.page_reg = 0;
    outb (host->card.page_reg, host->card.io_page);

    /*
     * Should get a reset from the card
     */
    while (!(inb (host->card.io_intr) & 8));
    sbic_arm_read (host->scsi.io_port, ASR);
    sbic_arm_read (host->scsi.io_port, SSR);

    /* setup sbic - WD33C93A */
    sbic_arm_write (host->scsi.io_port, OWNID, OWNID_EAF | host->host->this_id);
    sbic_arm_write (host->scsi.io_port, CMND, CMND_RESET);

    /*
     * Command should cause a reset interrupt
     */
    while (!(inb (host->card.io_intr) & 8));
    sbic_arm_read (host->scsi.io_port, ASR);
    if (sbic_arm_read (host->scsi.io_port, SSR) != 0x01)
	printk (KERN_CRIT "scsi%d: WD33C93A didn't give enhanced reset interrupt\n",
		host->host->host_no);

    sbic_arm_write (host->scsi.io_port, CTRL, INIT_SBICDMA | CTRL_IDI);
    sbic_arm_write (host->scsi.io_port, TIMEOUT, TIMEOUT_TIME);
    sbic_arm_write (host->scsi.io_port, SYNCHTRANSFER, SYNCHTRANSFER_2DBA);
    sbic_arm_write (host->scsi.io_port, SOURCEID, SOURCEID_ER | SOURCEID_DSP);

    host->card.page_reg = 0x40;
    outb (host->card.page_reg, host->card.io_page);

    /* setup dmac - uPC71071 */
    dmac_write (host->dma.io_port, INIT, 0);
    dmac_write (host->dma.io_port, INIT, INIT_8BIT);
    dmac_write (host->dma.io_port, CHANNEL, CHANNEL_0);
    dmac_write (host->dma.io_port, DEVCON0, INIT_DEVCON0);
    dmac_write (host->dma.io_port, DEVCON1, INIT_DEVCON1);

    host->SCpnt = NULL;
    host->scsi.phase = PHASE_IDLE;
    host->scsi.disconnectable = 0;

    for (i = 0; i < 8; i++) {
	host->busyluns[i] = 0;
	host->device[i].sync_state = SYNC_NEGOCIATE;
	host->device[i].disconnect_ok = 1;
    }

    /* wait 25 cs.  SCSI standard says 250ms. */
    acornscsi_csdelay (25);
}

/*=============================================================================================
 * Utility routines (eg. debug)
 */
#ifdef CONFIG_ACORNSCSI_CONSTANTS
static char *acornscsi_interrupttype[] = {
  "rst",  "suc",  "p/a",  "3",
  "term", "5",	  "6",	  "7",
  "serv", "9",	  "a",	  "b",
  "c",	  "d",	  "e",	  "f"
};

static signed char acornscsi_map[] = {
  0,  1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 -1,  2, -1, -1,  -1, -1,  3, -1,   4,	5,  6,	7,   8,  9, 10, 11,
 12, 13, 14, -1,  -1, -1, -1, -1,   4,	5,  6,	7,   8,  9, 10, 11,
 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 15, 16, 17, 18,  19, -1, -1, 20,   4,	5,  6,	7,   8,  9, 10, 11,
 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 21, 22, -1, -1,  -1, 23, -1, -1,   4,	5,  6,	7,   8,  9, 10, 11,
 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1
};      

static char *acornscsi_interruptcode[] = {
    /* 0 */
    "reset - normal mode",	/* 00 */
    "reset - advanced mode",	/* 01 */

    /* 2 */
    "sel",			/* 11 */
    "sel+xfer", 		/* 16 */
    "data-out", 		/* 18 */
    "data-in",			/* 19 */
    "cmd",			/* 1A */
    "stat",			/* 1B */
    "??-out",			/* 1C */
    "??-in",			/* 1D */
    "msg-out",			/* 1E */
    "msg-in",			/* 1F */

    /* 12 */
    "/ACK asserted",		/* 20 */
    "save-data-ptr",		/* 21 */
    "{re}sel",			/* 22 */

    /* 15 */
    "inv cmd",			/* 40 */
    "unexpected disconnect",	/* 41 */
    "sel timeout",		/* 42 */
    "P err",			/* 43 */
    "P err+ATN",		/* 44 */
    "bad status byte",		/* 47 */

    /* 21 */
    "resel, no id",		/* 80 */
    "resel",			/* 81 */
    "discon",			/* 85 */
};

static
void print_scsi_status (unsigned int ssr)
{
    if (acornscsi_map[ssr] != -1)
	printk ("%s:%s",
		acornscsi_interrupttype[(ssr >> 4)],
		acornscsi_interruptcode[acornscsi_map[ssr]]);
    else
	printk ("%X:%X", ssr >> 4, ssr & 0x0f);    
}    
#endif

static
void print_sbic_status (int asr, int ssr, int cmdphase)
{
#ifdef CONFIG_ACORNSCSI_CONSTANTS
	printk ("sbic: %c%c%c%c%c%c ",
		asr & ASR_INT ? 'I' : 'i',
		asr & ASR_LCI ? 'L' : 'l',
		asr & ASR_BSY ? 'B' : 'b',
		asr & ASR_CIP ? 'C' : 'c',
		asr & ASR_PE  ? 'P' : 'p',
		asr & ASR_DBR ? 'D' : 'd');
	printk ("scsi: ");
	print_scsi_status (ssr);
	printk (" ph %02X\n", cmdphase);
#else
	printk ("sbic: %02X scsi: %X:%X ph: %02X\n",
		asr, (ssr & 0xf0)>>4, ssr & 0x0f, cmdphase);
#endif
}

static
void acornscsi_dumplog (AS_Host *host, int target)