// SPDX-License-Identifier: GPL-2.0-only
/*
 * Zalon 53c7xx device driver.
 * By Richard Hirst (rhirst@linuxcare.com)
 */

#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/types.h>
#include <asm/hardware.h>
#include <asm/io.h>

#include "../parisc/gsc.h"

#include "ncr53c8xx.h"

MODULE_AUTHOR("Richard Hirst");
MODULE_DESCRIPTION("Bluefish/Zalon 720 SCSI Driver");
MODULE_LICENSE("GPL");

#define GSC_SCSI_ZALON_OFFSET 0x800

#define IO_MODULE_EIM           (1*4)
#define IO_MODULE_DC_ADATA      (2*4)
#define IO_MODULE_II_CDATA      (3*4)
#define IO_MODULE_IO_COMMAND    (12*4)
#define IO_MODULE_IO_STATUS     (13*4)

#define IOSTATUS_RY             0x40
#define IOSTATUS_FE             0x80
#define IOIIDATA_SMINT5L        0x40000000
#define IOIIDATA_MINT5EN        0x20000000
#define IOIIDATA_PACKEN         0x10000000
#define IOIIDATA_PREFETCHEN     0x08000000
#define IOIIDATA_IOII           0x00000020

#define CMD_RESET               5

static struct ncr_chip zalon720_chip __initdata = {
        .revision_id =  0x0f,
        .burst_max =    3,
        .offset_max =   8,
        .nr_divisor =   4,
        .features =     FE_WIDE | FE_DIFF | FE_EHP| FE_MUX | FE_EA,
};



#if 0
/* FIXME:
 * Is this function dead code? or is someone planning on using it in the
 * future.  The clock = (int) pdc_result[16] does not look correct to
 * me ... I think it should be iodc_data[16].  Since this cause a compile
 * error with the new encapsulated PDC, I'm not compiling in this function.
 * - RB
 */
/* poke SCSI clock out of iodc data */

static u8 iodc_data[32] __attribute__ ((aligned (64)));
static unsigned long pdc_result[32] __attribute__ ((aligned (16))) ={0,0,0,0};

static int 
lasi_scsi_clock(void * hpa, int defaultclock)
{
        int clock, status;

        status = pdc_iodc_read(&pdc_result, hpa, 0, &iodc_data, 32 );
        if (status == PDC_RET_OK) {
                clock = (int) pdc_result[16];
        } else {
                printk(KERN_WARNING "%s: pdc_iodc_read returned %d\n", __func__, status);
                clock = defaultclock; 
        }

        printk(KERN_DEBUG "%s: SCSI clock %d\n", __func__, clock);
        return clock;
}
#endif

static struct scsi_host_template zalon7xx_template = {
        .module         = THIS_MODULE,
        .proc_name      = "zalon7xx",
};

static int __init
zalon_probe(struct parisc_device *dev)
{
        struct gsc_irq gsc_irq;
        u32 zalon_vers;
        int error = -ENODEV;
        void __iomem *zalon = ioremap(dev->hpa.start, 4096);
        void __iomem *io_port = zalon + GSC_SCSI_ZALON_OFFSET;
        static int unit = 0;
        struct Scsi_Host *host;
        struct ncr_device device;

        __raw_writel(CMD_RESET, zalon + IO_MODULE_IO_COMMAND);
        while (!(__raw_readl(zalon + IO_MODULE_IO_STATUS) & IOSTATUS_RY))
                cpu_relax();
        __raw_writel(IOIIDATA_MINT5EN | IOIIDATA_PACKEN | IOIIDATA_PREFETCHEN,
                zalon + IO_MODULE_II_CDATA);

        /* XXX: Save the Zalon version for bug workarounds? */
        zalon_vers = (__raw_readl(zalon + IO_MODULE_II_CDATA) >> 24) & 0x07;

        /* Setup the interrupts first.
        ** Later on request_irq() will register the handler.
        */
        dev->irq = gsc_alloc_irq(&gsc_irq);

        printk(KERN_INFO "%s: Zalon version %d, IRQ %d\n", __func__,
                zalon_vers, dev->irq);

        __raw_writel(gsc_irq.txn_addr | gsc_irq.txn_data, zalon + IO_MODULE_EIM);

        if (zalon_vers == 0)
                printk(KERN_WARNING "%s: Zalon 1.1 or earlier\n", __func__);

        memset(&device, 0, sizeof(struct ncr_device));

        /* The following three are needed before any other access. */
        __raw_writeb(0x20, io_port + 0x38); /* DCNTL_REG,  EA  */
        __raw_writeb(0x04, io_port + 0x1b); /* CTEST0_REG, EHP */
        __raw_writeb(0x80, io_port + 0x22); /* CTEST4_REG, MUX */

        /* Initialise ncr_device structure with items required by ncr_attach. */
        device.chip             = zalon720_chip;
        device.host_id          = 7;
        device.dev              = &dev->dev;
        device.slot.base        = dev->hpa.start + GSC_SCSI_ZALON_OFFSET;
        device.slot.base_v      = io_port;
        device.slot.irq         = dev->irq;
        device.differential     = 2;

        host = ncr_attach(&zalon7xx_template, unit, &device);
        if (!host)
                return -ENODEV;

        if (request_irq(dev->irq, ncr53c8xx_intr, IRQF_SHARED, "zalon", host)) {
          dev_printk(KERN_ERR, &dev->dev, "irq problem with %d, detaching\n ",
                     dev->irq);
                goto fail;
        }

        unit++;

        dev_set_drvdata(&dev->dev, host);

        error = scsi_add_host(host, &dev->dev);
        if (error)
                goto fail_free_irq;

        scsi_scan_host(host);
        return 0;

 fail_free_irq:
        free_irq(dev->irq, host);
 fail:
        ncr53c8xx_release(host);
        return error;
}

static const struct parisc_device_id zalon_tbl[] __initconst = {
        { HPHW_A_DMA, HVERSION_REV_ANY_ID, HVERSION_ANY_ID, 0x00089 }, 
        { 0, }
};

MODULE_DEVICE_TABLE(parisc, zalon_tbl);

static void __exit zalon_remove(struct parisc_device *dev)
{
        struct Scsi_Host *host = dev_get_drvdata(&dev->dev);

        scsi_remove_host(host);
        ncr53c8xx_release(host);
        free_irq(dev->irq, host);
}

static struct parisc_driver zalon_driver __refdata = {
        .name =         "zalon",
        .id_table =     zalon_tbl,
        .probe =        zalon_probe,
        .remove =       __exit_p(zalon_remove),
};

static int __init zalon7xx_init(void)
{
        int ret = ncr53c8xx_init();
        if (!ret)
                ret = register_parisc_driver(&zalon_driver);
        if (ret)
                ncr53c8xx_exit();
        return ret;
}

static void __exit zalon7xx_exit(void)
{
        unregister_parisc_driver(&zalon_driver);
        ncr53c8xx_exit();
}

module_init(zalon7xx_init);
module_exit(zalon7xx_exit);