acornscsi.c

h内核

/*
 *  linux/drivers/acorn/scsi/acornscsi.c
 *
 *  Acorn SCSI 3 driver
 *  By R.M.King.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * 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.
 *  12-Oct-1997	RMK	Added catch for re-entering interrupt routine.
 *  15-Oct-1997	RMK	Improved handling of commands.
 *  27-Jun-1998	RMK	Changed asm/delay.h to linux/delay.h.
 *  13-Dec-1998	RMK	Better abort code and command handling.  Extra state
 *			transitions added to allow dodgy devices to work.
 */
#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)

/* 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'.
 *
 * Also note that CONFIG_SCSI_ACORNSCSI_TAGGED_QUEUE is normally set in the config
 * scripts, but disabled here.  Once debugged, remove the #undef, otherwise to debug,
 * comment out the undef.
 */
#undef CONFIG_SCSI_ACORNSCSI_TAGGED_QUEUE
/*
 * SCSI-II Linked command support.
 *
 * The higher level code doesn't support linked commands yet, and so the option
 * is undef'd here.
 */
#undef CONFIG_SCSI_ACORNSCSI_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 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 [don't remove this option]
 * If not set, then use PIO mode (not currently supported).
 */
#define USE_DMAC

/*
 * ====================================================================================
 */

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

#ifndef STRINGIFY
#define STRINGIFY(x) #x
#endif
#define STRx(x) STRINGIFY(x)
#define NO_WRITE_STR STRx(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/ioport.h>
#include <linux/blkdev.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/init.h>
#include <linux/bitops.h>

#include <asm/system.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/ecard.h>

#include "../scsi.h"
#include <scsi/scsi_host.h>
#include "acornscsi.h"
#include "msgqueue.h"
#include "scsi.h"

#include <scsi/scsicam.h>

#define VER_MAJOR 2
#define VER_MINOR 0
#define VER_PATCH 6

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

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

#ifdef USE_DMAC
/*
 * 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)

#define scsi_xferred	have_data_in

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

#define STATUS_BUFFER_TO_PRINT	24

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

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)
{
    __raw_writeb(reg, io_port);
    __raw_writeb(value, io_port + 4);
}

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

static inline
int sbic_arm_read(unsigned int io_port, int reg)
{
    if(reg == SBIC_ASR)
	   return __raw_readl(io_port) & 255;
    __raw_writeb(reg, io_port);
    return __raw_readl(io_port + 4) & 255;
}

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

#ifdef USE_DMAC
#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, DMAC_TXADRHI) << 16 |
	   dmac_read(io_port, DMAC_TXADRMD) << 8 |
	   dmac_read(io_port, DMAC_TXADRLO);
}

static
void acornscsi_dumpdma(AS_Host *host, char *where)
{
	unsigned int mode, addr, len;

	mode = dmac_read(host->dma.io_port, DMAC_MODECON);
	addr = dmac_address(host->dma.io_port);
	len  = dmac_read(host->dma.io_port, DMAC_TXCNTHI) << 8 |
	       dmac_read(host->dma.io_port, DMAC_TXCNTLO);

	printk("scsi%d: %s: DMAC %02x @%06x+%04x msk %02x, ",
		host->host->host_no, where,
		mode, addr, (len + 1) & 0xffff,
		dmac_read(host->dma.io_port, DMAC_MASKREG));

	printk("DMA @%06x, ", host->dma.start_addr);
	printk("BH @%p +%04x, ", host->scsi.SCp.ptr,
		host->scsi.SCp.this_residual);
	printk("DT @+%04x ST @+%04x", host->dma.transferred,
		host->scsi.SCp.scsi_xferred);
	printk("\n");
}
#endif

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

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

    return length;
}

static int
acornscsi_sbic_wait(AS_Host *host, int stat_mask, int stat, int timeout, char *msg)
{
	int asr;

	do {
		asr = sbic_arm_read(host->scsi.io_port, SBIC_ASR);

		if ((asr & stat_mask) == stat)
			return 0;

		udelay(1);
	} while (--timeout);

	printk("scsi%d: timeout while %s\n", host->host->host_no, msg);

	return -1;
}

static
int acornscsi_sbic_issuecmd(AS_Host *host, int command)
{
    if (acornscsi_sbic_wait(host, ASR_CIP, 0, 1000, "issuing command"))
	return -1;

    sbic_arm_write(host->scsi.io_port, SBIC_CMND, command);

    return 0;
}

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

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

    local_save_flags(flags);
    local_irq_enable();

    while (time_before(jiffies, target_jiffies)) barrier();

    local_irq_restore(flags);
}

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

    /* 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
     */
    timeout = 1000;
    do {
	if (inb(host->card.io_intr) & 8)
	    break;
	udelay(1);
    } while (--timeout);

    if (timeout == 0)
	printk("scsi%d: timeout while resetting card\n",
		host->host->host_no);

    sbic_arm_read(host->scsi.io_port, SBIC_ASR);
    sbic_arm_read(host->scsi.io_port, SBIC_SSR);

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

    /*
     * Command should cause a reset interrupt
     */
    timeout = 1000;
    do {
	if (inb(host->card.io_intr) & 8)
	    break;
	udelay(1);
    } while (--timeout);

    if (timeout == 0)
	printk("scsi%d: timeout while resetting card\n",
		host->host->host_no);

    sbic_arm_read(host->scsi.io_port, SBIC_ASR);
    if (sbic_arm_read(host->scsi.io_port, SBIC_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, SBIC_CTRL, INIT_SBICDMA | CTRL_IDI);
    sbic_arm_write(host->scsi.io_port, SBIC_TIMEOUT, TIMEOUT_TIME);
    sbic_arm_write(host->scsi.io_port, SBIC_SYNCHTRANSFER, SYNCHTRANSFER_2DBA);
    sbic_arm_write(host->scsi.io_port, SBIC_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, DMAC_INIT, 0);
#ifdef USE_DMAC
    dmac_write(host->dma.io_port, DMAC_INIT, INIT_8BIT);
    dmac_write(host->dma.io_port, DMAC_CHANNEL, CHANNEL_0);
    dmac_write(host->dma.io_port, DMAC_DEVCON0, INIT_DEVCON0);
    dmac_write(host->dma.io_port, DMAC_DEVCON1, INIT_DEVCON1);
#endif

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

    memset(host->busyluns, 0, sizeof(host->busyluns));

    for (i = 0; i < 8; i++) {
	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 */