/*
 *  Copyright (C) 1998-2000 Andreas S. Krebs (akrebs@altavista.net), Maintainer
 *  Copyright (C) 1998-2002 Andre Hedrick <andre@linux-ide.org>, Integrator
 *  Copyright (C) 2007-2011 Bartlomiej Zolnierkiewicz
 *
 * CYPRESS CY82C693 chipset IDE controller
 *
 * The CY82C693 chipset is used on Digital's PC-Alpha 164SX boards.
 */

#include <linux/module.h>
#include <linux/types.h>
#include <linux/pci.h>
#include <linux/ide.h>
#include <linux/init.h>

#include <asm/io.h>

#define DRV_NAME "cy82c693"

/*
 *      NOTE: the value for busmaster timeout is tricky and I got it by
 *      trial and error!  By using a to low value will cause DMA timeouts
 *      and drop IDE performance, and by using a to high value will cause
 *      audio playback to scatter.
 *      If you know a better value or how to calc it, please let me know.
 */

/* twice the value written in cy82c693ub datasheet */
#define BUSMASTER_TIMEOUT       0x50
/*
 * the value above was tested on my machine and it seems to work okay
 */

/* here are the offset definitions for the registers */
#define CY82_IDE_CMDREG         0x04
#define CY82_IDE_ADDRSETUP      0x48
#define CY82_IDE_MASTER_IOR     0x4C
#define CY82_IDE_MASTER_IOW     0x4D
#define CY82_IDE_SLAVE_IOR      0x4E
#define CY82_IDE_SLAVE_IOW      0x4F
#define CY82_IDE_MASTER_8BIT    0x50
#define CY82_IDE_SLAVE_8BIT     0x51

#define CY82_INDEX_PORT         0x22
#define CY82_DATA_PORT          0x23

#define CY82_INDEX_CHANNEL0     0x30
#define CY82_INDEX_CHANNEL1     0x31
#define CY82_INDEX_TIMEOUT      0x32

/*
 * set DMA mode a specific channel for CY82C693
 */

static void cy82c693_set_dma_mode(ide_hwif_t *hwif, ide_drive_t *drive)
{
        const u8 mode = drive->dma_mode;
        u8 single = (mode & 0x10) >> 4, index = 0, data = 0;

        index = hwif->channel ? CY82_INDEX_CHANNEL1 : CY82_INDEX_CHANNEL0;

        data = (mode & 3) | (single << 2);

        outb(index, CY82_INDEX_PORT);
        outb(data, CY82_DATA_PORT);

        /*
         * note: below we set the value for Bus Master IDE TimeOut Register
         * I'm not absolutely sure what this does, but it solved my problem
         * with IDE DMA and sound, so I now can play sound and work with
         * my IDE driver at the same time :-)
         *
         * If you know the correct (best) value for this register please
         * let me know - ASK
         */

        data = BUSMASTER_TIMEOUT;
        outb(CY82_INDEX_TIMEOUT, CY82_INDEX_PORT);
        outb(data, CY82_DATA_PORT);
}

static void cy82c693_set_pio_mode(ide_hwif_t *hwif, ide_drive_t *drive)
{
        struct pci_dev *dev = to_pci_dev(hwif->dev);
        int bus_speed = ide_pci_clk ? ide_pci_clk : 33;
        const unsigned long T = 1000000 / bus_speed;
        unsigned int addrCtrl;
        struct ide_timing t;
        u8 time_16, time_8;

        /* select primary or secondary channel */
        if (drive->dn > 1) {  /* drive is on the secondary channel */
                dev = pci_get_slot(dev->bus, dev->devfn+1);
                if (!dev) {
                        printk(KERN_ERR "%s: tune_drive: "
                                "Cannot find secondary interface!\n",
                                drive->name);
                        return;
                }
        }

        ide_timing_compute(drive, drive->pio_mode, &t, T, 1);

        time_16 = clamp_val(t.recover - 1, 0, 15) |
                  (clamp_val(t.active - 1, 0, 15) << 4);
        time_8 = clamp_val(t.act8b - 1, 0, 15) |
                 (clamp_val(t.rec8b - 1, 0, 15) << 4);

        /* now let's write  the clocks registers */
        if ((drive->dn & 1) == 0) {
                /*
                 * set master drive
                 * address setup control register
                 * is 32 bit !!!
                 */
                pci_read_config_dword(dev, CY82_IDE_ADDRSETUP, &addrCtrl);

                addrCtrl &= (~0xF);
                addrCtrl |= clamp_val(t.setup - 1, 0, 15);
                pci_write_config_dword(dev, CY82_IDE_ADDRSETUP, addrCtrl);

                /* now let's set the remaining registers */
                pci_write_config_byte(dev, CY82_IDE_MASTER_IOR, time_16);
                pci_write_config_byte(dev, CY82_IDE_MASTER_IOW, time_16);
                pci_write_config_byte(dev, CY82_IDE_MASTER_8BIT, time_8);
        } else {
                /*
                 * set slave drive
                 * address setup control register
                 * is 32 bit !!!
                 */
                pci_read_config_dword(dev, CY82_IDE_ADDRSETUP, &addrCtrl);

                addrCtrl &= (~0xF0);
                addrCtrl |= (clamp_val(t.setup - 1, 0, 15) << 4);
                pci_write_config_dword(dev, CY82_IDE_ADDRSETUP, addrCtrl);

                /* now let's set the remaining registers */
                pci_write_config_byte(dev, CY82_IDE_SLAVE_IOR, time_16);
                pci_write_config_byte(dev, CY82_IDE_SLAVE_IOW, time_16);
                pci_write_config_byte(dev, CY82_IDE_SLAVE_8BIT, time_8);
        }
        if (drive->dn > 1)
                pci_dev_put(dev);
}

static void init_iops_cy82c693(ide_hwif_t *hwif)
{
        static ide_hwif_t *primary;
        struct pci_dev *dev = to_pci_dev(hwif->dev);

        if (PCI_FUNC(dev->devfn) == 1)
                primary = hwif;
        else {
                hwif->mate = primary;
                hwif->channel = 1;
        }
}

static const struct ide_port_ops cy82c693_port_ops = {
        .set_pio_mode           = cy82c693_set_pio_mode,
        .set_dma_mode           = cy82c693_set_dma_mode,
};

static const struct ide_port_info cy82c693_chipset = {
        .name           = DRV_NAME,
        .init_iops      = init_iops_cy82c693,
        .port_ops       = &cy82c693_port_ops,
        .host_flags     = IDE_HFLAG_SINGLE,
        .pio_mask       = ATA_PIO4,
        .swdma_mask     = ATA_SWDMA2,
        .mwdma_mask     = ATA_MWDMA2,
};

static int cy82c693_init_one(struct pci_dev *dev,
                             const struct pci_device_id *id)
{
        struct pci_dev *dev2;
        int ret = -ENODEV;

        /* CY82C693 is more than only a IDE controller.
           Function 1 is primary IDE channel, function 2 - secondary. */
        if ((dev->class >> 8) == PCI_CLASS_STORAGE_IDE &&
            PCI_FUNC(dev->devfn) == 1) {
                dev2 = pci_get_slot(dev->bus, dev->devfn + 1);
                ret = ide_pci_init_two(dev, dev2, &cy82c693_chipset, NULL);
                if (ret)
                        pci_dev_put(dev2);
        }
        return ret;
}

static void cy82c693_remove(struct pci_dev *dev)
{
        struct ide_host *host = pci_get_drvdata(dev);
        struct pci_dev *dev2 = host->dev[1] ? to_pci_dev(host->dev[1]) : NULL;

        ide_pci_remove(dev);
        pci_dev_put(dev2);
}

static const struct pci_device_id cy82c693_pci_tbl[] = {
        { PCI_VDEVICE(CONTAQ, PCI_DEVICE_ID_CONTAQ_82C693), 0 },
        { 0, },
};
MODULE_DEVICE_TABLE(pci, cy82c693_pci_tbl);

static struct pci_driver cy82c693_pci_driver = {
        .name           = "Cypress_IDE",
        .id_table       = cy82c693_pci_tbl,
        .probe          = cy82c693_init_one,
        .remove         = cy82c693_remove,
        .suspend        = ide_pci_suspend,
        .resume         = ide_pci_resume,
};

static int __init cy82c693_ide_init(void)
{
        return ide_pci_register_driver(&cy82c693_pci_driver);
}

static void __exit cy82c693_ide_exit(void)
{
        pci_unregister_driver(&cy82c693_pci_driver);
}

module_init(cy82c693_ide_init);
module_exit(cy82c693_ide_exit);

MODULE_AUTHOR("Andreas Krebs, Andre Hedrick, Bartlomiej Zolnierkiewicz");
MODULE_DESCRIPTION("PCI driver module for the Cypress CY82C693 IDE");
MODULE_LICENSE("GPL");