cumana_2.c

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/*
 *  linux/drivers/acorn/scsi/cumana_2.c
 *
 *  Copyright (C) 1997-2005 Russell 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.
 *
 *  Changelog:
 *   30-08-1997 RMK 0.0.0   Created, READONLY version.
 *   22-01-1998 RMK 0.0.1   Updated to 2.1.80.
 *   15-04-1998 RMK 0.0.1   Only do PIO if FAS216 will allow it.
 *   02-05-1998 RMK 0.0.2   Updated & added DMA support.
 *   27-06-1998 RMK     Changed asm/delay.h to linux/delay.h
 *   18-08-1998 RMK 0.0.3   Fixed synchronous transfer depth.
 *   02-04-2000 RMK 0.0.4   Updated for new error handling code.
 */
#include <linux/module.h>
#include <linux/blkdev.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/ioport.h>
#include <linux/proc_fs.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/init.h>
#include <linux/dma-mapping.h>

#include <asm/dma.h>
#include <asm/ecard.h>
#include <asm/io.h>
#include <asm/pgtable.h>

#include "../scsi.h"
#include <scsi/scsi_host.h>
#include "fas216.h"
#include "scsi.h"

#include <scsi/scsicam.h>

#define CUMANASCSI2_STATUS      (0x0000)
#define STATUS_INT          (1 << 0)
#define STATUS_DRQ          (1 << 1)
#define STATUS_LATCHED          (1 << 3)

#define CUMANASCSI2_ALATCH      (0x0014)
#define ALATCH_ENA_INT          (3)
#define ALATCH_DIS_INT          (2)
#define ALATCH_ENA_TERM         (5)
#define ALATCH_DIS_TERM         (4)
#define ALATCH_ENA_BIT32        (11)
#define ALATCH_DIS_BIT32        (10)
#define ALATCH_ENA_DMA          (13)
#define ALATCH_DIS_DMA          (12)
#define ALATCH_DMA_OUT          (15)
#define ALATCH_DMA_IN           (14)

#define CUMANASCSI2_PSEUDODMA       (0x0200)

#define CUMANASCSI2_FAS216_OFFSET   (0x0300)
#define CUMANASCSI2_FAS216_SHIFT    2

/*
 * Version
 */
#define VERSION "1.00 (13/11/2002 2.5.47)"

/*
 * Use term=0,1,0,0,0 to turn terminators on/off
 */
static int term[MAX_ECARDS] = { 1, 1, 1, 1, 1, 1, 1, 1 };

#define NR_SG   256

struct cumanascsi2_info {
    FAS216_Info     info;
    struct expansion_card   *ec;
    void __iomem        *base;
    unsigned int        terms;      /* Terminator state */
    struct scatterlist  sg[NR_SG];  /* Scatter DMA list */
};

#define CSTATUS_IRQ (1 << 0)
#define CSTATUS_DRQ (1 << 1)

/* Prototype: void cumanascsi_2_irqenable(ec, irqnr)
 * Purpose  : Enable interrupts on Cumana SCSI 2 card
 * Params   : ec    - expansion card structure
 *          : irqnr - interrupt number
 */
static void
cumanascsi_2_irqenable(struct expansion_card *ec, int irqnr)
{
    struct cumanascsi2_info *info = ec->irq_data;
    writeb(ALATCH_ENA_INT, info->base + CUMANASCSI2_ALATCH);
}

/* Prototype: void cumanascsi_2_irqdisable(ec, irqnr)
 * Purpose  : Disable interrupts on Cumana SCSI 2 card
 * Params   : ec    - expansion card structure
 *          : irqnr - interrupt number
 */
static void
cumanascsi_2_irqdisable(struct expansion_card *ec, int irqnr)
{
    struct cumanascsi2_info *info = ec->irq_data;
    writeb(ALATCH_DIS_INT, info->base + CUMANASCSI2_ALATCH);
}

static const expansioncard_ops_t cumanascsi_2_ops = {
    .irqenable  = cumanascsi_2_irqenable,
    .irqdisable = cumanascsi_2_irqdisable,
};

/* Prototype: void cumanascsi_2_terminator_ctl(host, on_off)
 * Purpose  : Turn the Cumana SCSI 2 terminators on or off
 * Params   : host   - card to turn on/off
 *          : on_off - !0 to turn on, 0 to turn off
 */
static void
cumanascsi_2_terminator_ctl(struct Scsi_Host *host, int on_off)
{
    struct cumanascsi2_info *info = (struct cumanascsi2_info *)host->hostdata;

    if (on_off) {
        info->terms = 1;
        writeb(ALATCH_ENA_TERM, info->base + CUMANASCSI2_ALATCH);
    } else {
        info->terms = 0;
        writeb(ALATCH_DIS_TERM, info->base + CUMANASCSI2_ALATCH);
    }
}

/* Prototype: void cumanascsi_2_intr(irq, *dev_id, *regs)
 * Purpose  : handle interrupts from Cumana SCSI 2 card
 * Params   : irq    - interrupt number
 *        dev_id - user-defined (Scsi_Host structure)
 */
static irqreturn_t
cumanascsi_2_intr(int irq, void *dev_id)
{
    struct cumanascsi2_info *info = dev_id;

    return fas216_intr(&info->info);
}

/* Prototype: fasdmatype_t cumanascsi_2_dma_setup(host, SCpnt, direction, min_type)
 * Purpose  : initialises DMA/PIO
 * Params   : host      - host
 *        SCpnt     - command
 *        direction - DMA on to/off of card
 *        min_type  - minimum DMA support that we must have for this transfer
 * Returns  : type of transfer to be performed
 */
static fasdmatype_t
cumanascsi_2_dma_setup(struct Scsi_Host *host, struct scsi_pointer *SCp,
               fasdmadir_t direction, fasdmatype_t min_type)
{
    struct cumanascsi2_info *info = (struct cumanascsi2_info *)host->hostdata;
    struct device *dev = scsi_get_device(host);
    int dmach = info->info.scsi.dma;

    writeb(ALATCH_DIS_DMA, info->base + CUMANASCSI2_ALATCH);

    if (dmach != NO_DMA &&
        (min_type == fasdma_real_all || SCp->this_residual >= 512)) {
        int bufs, map_dir, dma_dir, alatch_dir;

        bufs = copy_SCp_to_sg(&info->sg[0], SCp, NR_SG);

        if (direction == DMA_OUT)
            map_dir = DMA_TO_DEVICE,
            dma_dir = DMA_MODE_WRITE,
            alatch_dir = ALATCH_DMA_OUT;
        else
            map_dir = DMA_FROM_DEVICE,
            dma_dir = DMA_MODE_READ,
            alatch_dir = ALATCH_DMA_IN;

        dma_map_sg(dev, info->sg, bufs, map_dir);

        disable_dma(dmach);
        set_dma_sg(dmach, info->sg, bufs);
        writeb(alatch_dir, info->base + CUMANASCSI2_ALATCH);
        set_dma_mode(dmach, dma_dir);
        enable_dma(dmach);
        writeb(ALATCH_ENA_DMA, info->base + CUMANASCSI2_ALATCH);
        writeb(ALATCH_DIS_BIT32, info->base + CUMANASCSI2_ALATCH);
        return fasdma_real_all;
    }

    /*
     * If we're not doing DMA,
     *  we'll do pseudo DMA
     */
    return fasdma_pio;
}

/*
 * Prototype: void cumanascsi_2_dma_pseudo(host, SCpnt, direction, transfer)
 * Purpose  : handles pseudo DMA
 * Params   : host      - host
 *        SCpnt     - command
 *        direction - DMA on to/off of card
 *        transfer  - minimum number of bytes we expect to transfer
 */
static void
cumanascsi_2_dma_pseudo(struct Scsi_Host *host, struct scsi_pointer *SCp,
            fasdmadir_t direction, int transfer)
{
    struct cumanascsi2_info *info = (struct cumanascsi2_info *)host->hostdata;
    unsigned int length;
    unsigned char *addr;

    length = SCp->this_residual;
    addr = SCp->ptr;

    if (direction == DMA_OUT)
#if 0
        while (length > 1) {
            unsigned long word;
            unsigned int status = readb(info->base + CUMANASCSI2_STATUS);

            if (status & STATUS_INT)
                goto end;

            if (!(status & STATUS_DRQ))
                continue;

            word = *addr | *(addr + 1) << 8;
            writew(word, info->base + CUMANASCSI2_PSEUDODMA);
            addr += 2;
            length -= 2;
        }
#else
        printk ("PSEUDO_OUT???\n");
#endif
    else {
        if (transfer && (transfer & 255)) {
            while (length >= 256) {
                unsigned int status = readb(info->base + CUMANASCSI2_STATUS);

                if (status & STATUS_INT)
                    return;
        
                if (!(status & STATUS_DRQ))
                    continue;

                readsw(info->base + CUMANASCSI2_PSEUDODMA,
                       addr, 256 >> 1);
                addr += 256;
                length -= 256;
            }
        }

        while (length > 0) {
            unsigned long word;
            unsigned int status = readb(info->base + CUMANASCSI2_STATUS);

            if (status & STATUS_INT)
                return;

            if (!(status & STATUS_DRQ))
                continue;

            word = readw(info->base + CUMANASCSI2_PSEUDODMA);
            *addr++ = word;
            if (--length > 0) {
                *addr++ = word >> 8;
                length --;
            }
        }
    }
}

/* Prototype: int cumanascsi_2_dma_stop(host, SCpnt)
 * Purpose  : stops DMA/PIO
 * Params   : host  - host
 *        SCpnt - command
 */
static void
cumanascsi_2_dma_stop(struct Scsi_Host *host, struct scsi_pointer *SCp)
{
    struct cumanascsi2_info *info = (struct cumanascsi2_info *)host->hostdata;
    if (info->info.scsi.dma != NO_DMA) {
        writeb(ALATCH_DIS_DMA, info->base + CUMANASCSI2_ALATCH);
        disable_dma(info->info.scsi.dma);
    }
}

/* Prototype: const char *cumanascsi_2_info(struct Scsi_Host * host)
 * Purpose  : returns a descriptive string about this interface,
 * Params   : host - driver host structure to return info for.
 * Returns  : pointer to a static buffer containing null terminated string.
 */
const char *cumanascsi_2_info(struct Scsi_Host *host)
{
    struct cumanascsi2_info *info = (struct cumanascsi2_info *)host->hostdata;
    static char string[150];

    sprintf(string, "%s (%s) in slot %d v%s terminators o%s",
        host->hostt->name, info->info.scsi.type, info->ec->slot_no,
        VERSION, info->terms ? "n" : "ff");

    return string;
}

/* Prototype: int cumanascsi_2_set_proc_info(struct Scsi_Host *host, char *buffer, int length)
 * Purpose  : Set a driver specific function
 * Params   : host   - host to setup
 *          : buffer - buffer containing string describing operation
 *          : length - length of string
 * Returns  : -EINVAL, or 0
 */
static int
cumanascsi_2_set_proc_info(struct Scsi_Host *host, char *buffer, int length)
{
    int ret = length;

    if (length >= 11 && strncmp(buffer, "CUMANASCSI2", 11) == 0) {
        buffer += 11;
        length -= 11;

        if (length >= 5 && strncmp(buffer, "term=", 5) == 0) {
            if (buffer[5] == '1')
                cumanascsi_2_terminator_ctl(host, 1);
            else if (buffer[5] == '0')
                cumanascsi_2_terminator_ctl(host, 0);
            else
                ret = -EINVAL;
        } else
            ret = -EINVAL;
    } else
        ret = -EINVAL;

    return ret;
}

/* Prototype: int cumanascsi_2_proc_info(char *buffer, char **start, off_t offset,
 *                   int length, int host_no, int inout)
 * Purpose  : Return information about the driver to a user process accessing
 *        the /proc filesystem.
 * Params   : buffer - a buffer to write information to
 *        start  - a pointer into this buffer set by this routine to the start
 *             of the required information.
 *        offset - offset into information that we have read up to.
 *        length - length of buffer
 *        host_no - host number to return information for
 *        inout  - 0 for reading, 1 for writing.
 * Returns  : length of data written to buffer.
 */
int cumanascsi_2_proc_info (struct Scsi_Host *host, char *buffer, char **start, off_t offset,
                int length, int inout)
{
    struct cumanascsi2_info *info;
    char *p = buffer;
    int pos;

    if (inout == 1)
        return cumanascsi_2_set_proc_info(host, buffer, length);

    info = (struct cumanascsi2_info *)host->hostdata;

    p += sprintf(p, "Cumana SCSI II driver v%s\n", VERSION);
    p += fas216_print_host(&info->info, p);
    p += sprintf(p, "Term    : o%s\n",
            info->terms ? "n" : "ff");

    p += fas216_print_stats(&info->info, p);
    p += fas216_print_devices(&info->info, p);

    *start = buffer + offset;
    pos = p - buffer - offset;
    if (pos > length)
        pos = length;

    return pos;
}

static struct scsi_host_template cumanascsi2_template = {
    .module             = THIS_MODULE,
    .proc_info          = cumanascsi_2_proc_info,
    .name               = "Cumana SCSI II",
    .info               = cumanascsi_2_info,
    .queuecommand           = fas216_queue_command,
    .eh_host_reset_handler      = fas216_eh_host_reset,
    .eh_bus_reset_handler       = fas216_eh_bus_reset,
    .eh_device_reset_handler    = fas216_eh_device_reset,
    .eh_abort_handler       = fas216_eh_abort,
    .can_queue          = 1,
    .this_id            = 7,
    .sg_tablesize           = SCSI_MAX_SG_CHAIN_SEGMENTS,
    .dma_boundary           = IOMD_DMA_BOUNDARY,
    .cmd_per_lun            = 1,
    .use_clustering         = DISABLE_CLUSTERING,
    .proc_name          = "cumanascsi2",
};

static int __devinit
cumanascsi2_probe(struct expansion_card *ec, const struct ecard_id *id)
{
    struct Scsi_Host *host;
    struct cumanascsi2_info *info;
    void __iomem *base;
    int ret;

    ret = ecard_request_resources(ec);
    if (ret)
        goto out;

    base = ecardm_iomap(ec, ECARD_RES_MEMC, 0, 0);
    if (!base) {
        ret = -ENOMEM;
        goto out_region;
    }

    host = scsi_host_alloc(&cumanascsi2_template,
                   sizeof(struct cumanascsi2_info));
    if (!host) {
        ret = -ENOMEM;
        goto out_region;
    }

    ecard_set_drvdata(ec, host);

    info = (struct cumanascsi2_info *)host->hostdata;
    info->ec    = ec;
    info->base  = base;

    cumanascsi_2_terminator_ctl(host, term[ec->slot_no]);

    info->info.scsi.io_base     = base + CUMANASCSI2_FAS216_OFFSET;
    info->info.scsi.io_shift    = CUMANASCSI2_FAS216_SHIFT;
    info->info.scsi.irq     = ec->irq;
    info->info.scsi.dma     = ec->dma;
    info->info.ifcfg.clockrate  = 40; /* MHz */
    info->info.ifcfg.select_timeout = 255;
    info->info.ifcfg.asyncperiod    = 200; /* ns */
    info->info.ifcfg.sync_max_depth = 7;
    info->info.ifcfg.cntl3      = CNTL3_BS8 | CNTL3_FASTSCSI | CNTL3_FASTCLK;
    info->info.ifcfg.disconnect_ok  = 1;
    info->info.ifcfg.wide_max_size  = 0;
    info->info.ifcfg.capabilities   = FASCAP_PSEUDODMA;
    info->info.dma.setup        = cumanascsi_2_dma_setup;
    info->info.dma.pseudo       = cumanascsi_2_dma_pseudo;
    info->info.dma.stop     = cumanascsi_2_dma_stop;

    ec->irqaddr = info->base + CUMANASCSI2_STATUS;
    ec->irqmask = STATUS_INT;

    ecard_setirq(ec, &cumanascsi_2_ops, info);

    ret = fas216_init(host);
    if (ret)
        goto out_free;

    ret = request_irq(ec->irq, cumanascsi_2_intr,
              IRQF_DISABLED, "cumanascsi2", info);
    if (ret) {
        printk("scsi%d: IRQ%d not free: %d\n",
               host->host_no, ec->irq, ret);
        goto out_release;
    }

    if (info->info.scsi.dma != NO_DMA) {
        if (request_dma(info->info.scsi.dma, "cumanascsi2")) {
            printk("scsi%d: DMA%d not free, using PIO\n",
                   host->host_no, info->info.scsi.dma);
            info->info.scsi.dma = NO_DMA;
        } else {
            set_dma_speed(info->info.scsi.dma, 180);
            info->info.ifcfg.capabilities |= FASCAP_DMA;
        }
    }

    ret = fas216_add(host, &ec->dev);
    if (ret == 0)
        goto out;

    if (info->info.scsi.dma != NO_DMA)
        free_dma(info->info.scsi.dma);
    free_irq(ec->irq, host);

 out_release:
    fas216_release(host);

 out_free:
    scsi_host_put(host);

 out_region:
    ecard_release_resources(ec);

 out:
    return ret;
}

static void __devexit cumanascsi2_remove(struct expansion_card *ec)
{
    struct Scsi_Host *host = ecard_get_drvdata(ec);
    struct cumanascsi2_info *info = (struct cumanascsi2_info *)host->hostdata;

    ecard_set_drvdata(ec, NULL);
    fas216_remove(host);

    if (info->info.scsi.dma != NO_DMA)
        free_dma(info->info.scsi.dma);
    free_irq(ec->irq, info);

    fas216_release(host);
    scsi_host_put(host);
    ecard_release_resources(ec);
}

static const struct ecard_id cumanascsi2_cids[] = {
    { MANU_CUMANA, PROD_CUMANA_SCSI_2 },
    { 0xffff, 0xffff },
};

static struct ecard_driver cumanascsi2_driver = {
    .probe      = cumanascsi2_probe,
    .remove     = __devexit_p(cumanascsi2_remove),
    .id_table   = cumanascsi2_cids,
    .drv = {
        .name       = "cumanascsi2",
    },
};

static int __init cumanascsi2_init(void)
{
    return ecard_register_driver(&cumanascsi2_driver);
}

static void __exit cumanascsi2_exit(void)
{
    ecard_remove_driver(&cumanascsi2_driver);
}

module_init(cumanascsi2_init);
module_exit(cumanascsi2_exit);

MODULE_AUTHOR("Russell King");
MODULE_DESCRIPTION("Cumana SCSI-2 driver for Acorn machines");
module_param_array(term, int, NULL, 0);
MODULE_PARM_DESC(term, "SCSI bus termination");
MODULE_LICENSE("GPL");