powertec.c

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/*
 *  linux/drivers/acorn/scsi/powertec.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.
 */
#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 POWERTEC_FAS216_OFFSET  0x3000
#define POWERTEC_FAS216_SHIFT   6

#define POWERTEC_INTR_STATUS    0x2000
#define POWERTEC_INTR_BIT   0x80

#define POWERTEC_RESET_CONTROL  0x1018
#define POWERTEC_RESET_BIT  1

#define POWERTEC_TERM_CONTROL   0x2018
#define POWERTEC_TERM_ENABLE    1

#define POWERTEC_INTR_CONTROL   0x101c
#define POWERTEC_INTR_ENABLE    1
#define POWERTEC_INTR_DISABLE   0

#define VERSION "1.10 (19/01/2003 2.5.59)"

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

#define NR_SG   256

struct powertec_info {
    FAS216_Info     info;
    struct expansion_card   *ec;
    void __iomem        *base;
    unsigned int        term_ctl;
    struct scatterlist  sg[NR_SG];
};

/* Prototype: void powertecscsi_irqenable(ec, irqnr)
 * Purpose  : Enable interrupts on Powertec SCSI card
 * Params   : ec    - expansion card structure
 *          : irqnr - interrupt number
 */
static void
powertecscsi_irqenable(struct expansion_card *ec, int irqnr)
{
    struct powertec_info *info = ec->irq_data;
    writeb(POWERTEC_INTR_ENABLE, info->base + POWERTEC_INTR_CONTROL);
}

/* Prototype: void powertecscsi_irqdisable(ec, irqnr)
 * Purpose  : Disable interrupts on Powertec SCSI card
 * Params   : ec    - expansion card structure
 *          : irqnr - interrupt number
 */
static void
powertecscsi_irqdisable(struct expansion_card *ec, int irqnr)
{
    struct powertec_info *info = ec->irq_data;
    writeb(POWERTEC_INTR_DISABLE, info->base + POWERTEC_INTR_CONTROL);
}

static const expansioncard_ops_t powertecscsi_ops = {
    .irqenable  = powertecscsi_irqenable,
    .irqdisable = powertecscsi_irqdisable,
};

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

    info->term_ctl = on_off ? POWERTEC_TERM_ENABLE : 0;
    writeb(info->term_ctl, info->base + POWERTEC_TERM_CONTROL);
}

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

    return fas216_intr(&info->info);
}

/* Prototype: fasdmatype_t powertecscsi_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
powertecscsi_dma_setup(struct Scsi_Host *host, struct scsi_pointer *SCp,
               fasdmadir_t direction, fasdmatype_t min_type)
{
    struct powertec_info *info = (struct powertec_info *)host->hostdata;
    struct device *dev = scsi_get_device(host);
    int dmach = info->info.scsi.dma;

    if (info->info.ifcfg.capabilities & FASCAP_DMA &&
        min_type == fasdma_real_all) {
        int bufs, map_dir, dma_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;
        else
            map_dir = DMA_FROM_DEVICE,
            dma_dir = DMA_MODE_READ;

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

        disable_dma(dmach);
        set_dma_sg(dmach, info->sg, bufs);
        set_dma_mode(dmach, dma_dir);
        enable_dma(dmach);
        return fasdma_real_all;
    }

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

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

/* Prototype: const char *powertecscsi_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 *powertecscsi_info(struct Scsi_Host *host)
{
    struct powertec_info *info = (struct powertec_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->term_ctl ? "n" : "ff");

    return string;
}

/* Prototype: int powertecscsi_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
powertecscsi_set_proc_info(struct Scsi_Host *host, char *buffer, int length)
{
    int ret = length;

    if (length >= 12 && strncmp(buffer, "POWERTECSCSI", 12) == 0) {
        buffer += 12;
        length -= 12;

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

    return ret;
}

/* Prototype: int powertecscsi_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
 *        inout   - 0 for reading, 1 for writing.
 * Returns  : length of data written to buffer.
 */
int powertecscsi_proc_info(struct Scsi_Host *host, char *buffer, char **start, off_t offset,
                int length, int inout)
{
    struct powertec_info *info;
    char *p = buffer;
    int pos;

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

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

    p += sprintf(p, "PowerTec SCSI driver v%s\n", VERSION);
    p += fas216_print_host(&info->info, p);
    p += sprintf(p, "Term    : o%s\n",
            info->term_ctl ? "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 ssize_t powertecscsi_show_term(struct device *dev, struct device_attribute *attr, char *buf)
{
    struct expansion_card *ec = ECARD_DEV(dev);
    struct Scsi_Host *host = ecard_get_drvdata(ec);
    struct powertec_info *info = (struct powertec_info *)host->hostdata;

    return sprintf(buf, "%d\n", info->term_ctl ? 1 : 0);
}

static ssize_t
powertecscsi_store_term(struct device *dev, struct device_attribute *attr, const char *buf, size_t len)
{
    struct expansion_card *ec = ECARD_DEV(dev);
    struct Scsi_Host *host = ecard_get_drvdata(ec);

    if (len > 1)
        powertecscsi_terminator_ctl(host, buf[0] != '0');

    return len;
}

static DEVICE_ATTR(bus_term, S_IRUGO | S_IWUSR,
           powertecscsi_show_term, powertecscsi_store_term);

static struct scsi_host_template powertecscsi_template = {
    .module             = THIS_MODULE,
    .proc_info          = powertecscsi_proc_info,
    .name               = "PowerTec SCSI",
    .info               = powertecscsi_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          = 8,
    .this_id            = 7,
    .sg_tablesize           = SCSI_MAX_SG_CHAIN_SEGMENTS,
    .dma_boundary           = IOMD_DMA_BOUNDARY,
    .cmd_per_lun            = 2,
    .use_clustering         = ENABLE_CLUSTERING,
    .proc_name          = "powertec",
};

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

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

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

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

    ecard_set_drvdata(ec, host);

    info = (struct powertec_info *)host->hostdata;
    info->base = base;
    powertecscsi_terminator_ctl(host, term[ec->slot_no]);

    info->ec = ec;
    info->info.scsi.io_base     = base + POWERTEC_FAS216_OFFSET;
    info->info.scsi.io_shift    = POWERTEC_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   = 0;
    info->info.dma.setup        = powertecscsi_dma_setup;
    info->info.dma.pseudo       = NULL;
    info->info.dma.stop     = powertecscsi_dma_stop;

    ec->irqaddr = base + POWERTEC_INTR_STATUS;
    ec->irqmask = POWERTEC_INTR_BIT;

    ecard_setirq(ec, &powertecscsi_ops, info);

    device_create_file(&ec->dev, &dev_attr_bus_term);

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

    ret = request_irq(ec->irq, powertecscsi_intr,
              IRQF_DISABLED, "powertec", 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, "powertec")) {
            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:
    device_remove_file(&ec->dev, &dev_attr_bus_term);
    scsi_host_put(host);

 out_region:
    ecard_release_resources(ec);

 out:
    return ret;
}

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

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

    device_remove_file(&ec->dev, &dev_attr_bus_term);

    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 powertecscsi_cids[] = {
    { MANU_ALSYSTEMS, PROD_ALSYS_SCSIATAPI },
    { 0xffff, 0xffff },
};

static struct ecard_driver powertecscsi_driver = {
    .probe      = powertecscsi_probe,
    .remove     = __devexit_p(powertecscsi_remove),
    .id_table   = powertecscsi_cids,
    .drv = {
        .name       = "powertecscsi",
    },
};

static int __init powertecscsi_init(void)
{
    return ecard_register_driver(&powertecscsi_driver);
}

static void __exit powertecscsi_exit(void)
{
    ecard_remove_driver(&powertecscsi_driver);
}

module_init(powertecscsi_init);
module_exit(powertecscsi_exit);

MODULE_AUTHOR("Russell King");
MODULE_DESCRIPTION("Powertec SCSI driver");
module_param_array(term, int, NULL, 0);
MODULE_PARM_DESC(term, "SCSI bus termination");
MODULE_LICENSE("GPL");