// SPDX-License-Identifier: GPL-2.0-only
/*
 * Oak Generic NCR5380 driver
 *
 * Copyright 1995-2002, Russell King
 */

#include <linux/module.h>
#include <linux/ioport.h>
#include <linux/blkdev.h>
#include <linux/init.h>

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

#include <scsi/scsi_host.h>

#define priv(host)                      ((struct NCR5380_hostdata *)(host)->hostdata)

#define NCR5380_read(reg)           readb(hostdata->io + ((reg) << 2))
#define NCR5380_write(reg, value)   writeb(value, hostdata->io + ((reg) << 2))

#define NCR5380_dma_xfer_len            NCR5380_dma_xfer_none
#define NCR5380_dma_recv_setup          oakscsi_pread
#define NCR5380_dma_send_setup          oakscsi_pwrite
#define NCR5380_dma_residual            NCR5380_dma_residual_none

#define NCR5380_queue_command           oakscsi_queue_command
#define NCR5380_info                    oakscsi_info

#define NCR5380_implementation_fields   /* none */

#include "../NCR5380.h"

#undef START_DMA_INITIATOR_RECEIVE_REG
#define START_DMA_INITIATOR_RECEIVE_REG (128 + 7)

#define STAT    ((128 + 16) << 2)
#define DATA    ((128 + 8) << 2)

static inline int oakscsi_pwrite(struct NCR5380_hostdata *hostdata,
                                 unsigned char *addr, int len)
{
  u8 __iomem *base = hostdata->io;

printk("writing %p len %d\n",addr, len);

  while(1)
  {
    int status;
    while (((status = readw(base + STAT)) & 0x100)==0);
  }
  return 0;
}

static inline int oakscsi_pread(struct NCR5380_hostdata *hostdata,
                                unsigned char *addr, int len)
{
  u8 __iomem *base = hostdata->io;

printk("reading %p len %d\n", addr, len);
  while(len > 0)
  {
    unsigned int status, timeout;
    unsigned long b;
    
    timeout = 0x01FFFFFF;
    
    while (((status = readw(base + STAT)) & 0x100)==0)
    {
      timeout--;
      if(status & 0x200 || !timeout)
      {
        printk("status = %08X\n", status);
        return -1;
      }
    }

    if(len >= 128)
    {
      readsw(base + DATA, addr, 128);
      addr += 128;
      len -= 128;
    }
    else
    {
      b = (unsigned long) readw(base + DATA);
      *addr ++ = b;
      len -= 1;
      if(len)
        *addr ++ = b>>8;
      len -= 1;
    }
  }
  return 0;
}

#undef STAT
#undef DATA

#include "../NCR5380.c"

static const struct scsi_host_template oakscsi_template = {
        .module                 = THIS_MODULE,
        .name                   = "Oak 16-bit SCSI",
        .info                   = oakscsi_info,
        .queuecommand           = oakscsi_queue_command,
        .eh_abort_handler       = NCR5380_abort,
        .eh_host_reset_handler  = NCR5380_host_reset,
        .can_queue              = 16,
        .this_id                = 7,
        .sg_tablesize           = SG_ALL,
        .cmd_per_lun            = 2,
        .dma_boundary           = PAGE_SIZE - 1,
        .proc_name              = "oakscsi",
        .cmd_size               = sizeof(struct NCR5380_cmd),
        .max_sectors            = 128,
};

static int oakscsi_probe(struct expansion_card *ec, const struct ecard_id *id)
{
        struct Scsi_Host *host;
        int ret;

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

        host = scsi_host_alloc(&oakscsi_template, sizeof(struct NCR5380_hostdata));
        if (!host) {
                ret = -ENOMEM;
                goto release;
        }

        priv(host)->io = ioremap(ecard_resource_start(ec, ECARD_RES_MEMC),
                                 ecard_resource_len(ec, ECARD_RES_MEMC));
        if (!priv(host)->io) {
                ret = -ENOMEM;
                goto unreg;
        }

        host->irq = NO_IRQ;

        ret = NCR5380_init(host, FLAG_DMA_FIXUP | FLAG_LATE_DMA_SETUP);
        if (ret)
                goto out_unmap;

        NCR5380_maybe_reset_bus(host);

        ret = scsi_add_host(host, &ec->dev);
        if (ret)
                goto out_exit;

        scsi_scan_host(host);
        goto out;

 out_exit:
        NCR5380_exit(host);
 out_unmap:
        iounmap(priv(host)->io);
 unreg:
        scsi_host_put(host);
 release:
        ecard_release_resources(ec);
 out:
        return ret;
}

static void oakscsi_remove(struct expansion_card *ec)
{
        struct Scsi_Host *host = ecard_get_drvdata(ec);
        void __iomem *base = priv(host)->io;

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

        NCR5380_exit(host);
        scsi_host_put(host);
        iounmap(base);
        ecard_release_resources(ec);
}

static const struct ecard_id oakscsi_cids[] = {
        { MANU_OAK, PROD_OAK_SCSI },
        { 0xffff, 0xffff }
};

static struct ecard_driver oakscsi_driver = {
        .probe          = oakscsi_probe,
        .remove         = oakscsi_remove,
        .id_table       = oakscsi_cids,
        .drv = {
                .name           = "oakscsi",
        },
};

static int __init oakscsi_init(void)
{
        return ecard_register_driver(&oakscsi_driver);
}

static void __exit oakscsi_exit(void)
{
        ecard_remove_driver(&oakscsi_driver);
}

module_init(oakscsi_init);
module_exit(oakscsi_exit);

MODULE_AUTHOR("Russell King");
MODULE_DESCRIPTION("Oak SCSI driver");
MODULE_LICENSE("GPL");