/*
 * pata-cs5530.c        - CS5530 PATA for new ATA layer
 *                        (C) 2005 Red Hat Inc
 *
 * based upon cs5530.c by Mark Lord.
 *
 * 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.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * Loosely based on the piix & svwks drivers.
 *
 * Documentation:
 *      Available from AMD web site.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/init.h>
#include <linux/blkdev.h>
#include <linux/delay.h>
#include <scsi/scsi_host.h>
#include <linux/libata.h>
#include <linux/dmi.h>

#define DRV_NAME        "pata_cs5530"
#define DRV_VERSION     "0.7.4"

static void __iomem *cs5530_port_base(struct ata_port *ap)
{
        unsigned long bmdma = (unsigned long)ap->ioaddr.bmdma_addr;

        return (void __iomem *)((bmdma & ~0x0F) + 0x20 + 0x10 * ap->port_no);
}

/**
 *      cs5530_set_piomode              -       PIO setup
 *      @ap: ATA interface
 *      @adev: device on the interface
 *
 *      Set our PIO requirements. This is fairly simple on the CS5530
 *      chips.
 */

static void cs5530_set_piomode(struct ata_port *ap, struct ata_device *adev)
{
        static const unsigned int cs5530_pio_timings[2][5] = {
                {0x00009172, 0x00012171, 0x00020080, 0x00032010, 0x00040010},
                {0xd1329172, 0x71212171, 0x30200080, 0x20102010, 0x00100010}
        };
        void __iomem *base = cs5530_port_base(ap);
        u32 tuning;
        int format;

        /* Find out which table to use */
        tuning = ioread32(base + 0x04);
        format = (tuning & 0x80000000UL) ? 1 : 0;

        /* Now load the right timing register */
        if (adev->devno)
                base += 0x08;

        iowrite32(cs5530_pio_timings[format][adev->pio_mode - XFER_PIO_0], base);
}

/**
 *      cs5530_set_dmamode              -       DMA timing setup
 *      @ap: ATA interface
 *      @adev: Device being configured
 *
 *      We cannot mix MWDMA and UDMA without reloading timings each switch
 *      master to slave. We track the last DMA setup in order to minimise
 *      reloads.
 */

static void cs5530_set_dmamode(struct ata_port *ap, struct ata_device *adev)
{
        void __iomem *base = cs5530_port_base(ap);
        u32 tuning, timing = 0;
        u8 reg;

        /* Find out which table to use */
        tuning = ioread32(base + 0x04);

        switch(adev->dma_mode) {
                case XFER_UDMA_0:
                        timing  = 0x00921250;break;
                case XFER_UDMA_1:
                        timing  = 0x00911140;break;
                case XFER_UDMA_2:
                        timing  = 0x00911030;break;
                case XFER_MW_DMA_0:
                        timing  = 0x00077771;break;
                case XFER_MW_DMA_1:
                        timing  = 0x00012121;break;
                case XFER_MW_DMA_2:
                        timing  = 0x00002020;break;
                default:
                        BUG();
        }
        /* Merge in the PIO format bit */
        timing |= (tuning & 0x80000000UL);
        if (adev->devno == 0) /* Master */
                iowrite32(timing, base + 0x04);
        else {
                if (timing & 0x00100000)
                        tuning |= 0x00100000;   /* UDMA for both */
                else
                        tuning &= ~0x00100000;  /* MWDMA for both */
                iowrite32(tuning, base + 0x04);
                iowrite32(timing, base + 0x0C);
        }

        /* Set the DMA capable bit in the BMDMA area */
        reg = ioread8(ap->ioaddr.bmdma_addr + ATA_DMA_STATUS);
        reg |= (1 << (5 + adev->devno));
        iowrite8(reg, ap->ioaddr.bmdma_addr + ATA_DMA_STATUS);

        /* Remember the last DMA setup we did */

        ap->private_data = adev;
}

/**
 *      cs5530_qc_issue         -       command issue
 *      @qc: command pending
 *
 *      Called when the libata layer is about to issue a command. We wrap
 *      this interface so that we can load the correct ATA timings if
 *      necessary.  Specifically we have a problem that there is only
 *      one MWDMA/UDMA bit.
 */

static unsigned int cs5530_qc_issue(struct ata_queued_cmd *qc)
{
        struct ata_port *ap = qc->ap;
        struct ata_device *adev = qc->dev;
        struct ata_device *prev = ap->private_data;

        /* See if the DMA settings could be wrong */
        if (ata_dma_enabled(adev) && adev != prev && prev != NULL) {
                /* Maybe, but do the channels match MWDMA/UDMA ? */
                if ((ata_using_udma(adev) && !ata_using_udma(prev)) ||
                    (ata_using_udma(prev) && !ata_using_udma(adev)))
                        /* Switch the mode bits */
                        cs5530_set_dmamode(ap, adev);
        }

        return ata_sff_qc_issue(qc);
}

static struct scsi_host_template cs5530_sht = {
        ATA_BMDMA_SHT(DRV_NAME),
        .sg_tablesize   = LIBATA_DUMB_MAX_PRD,
};

static struct ata_port_operations cs5530_port_ops = {
        .inherits       = &ata_bmdma_port_ops,

        .qc_prep        = ata_sff_dumb_qc_prep,
        .qc_issue       = cs5530_qc_issue,

        .cable_detect   = ata_cable_40wire,
        .set_piomode    = cs5530_set_piomode,
        .set_dmamode    = cs5530_set_dmamode,
};

static const struct dmi_system_id palmax_dmi_table[] = {
        {
                .ident = "Palmax PD1100",
                .matches = {
                        DMI_MATCH(DMI_SYS_VENDOR, "Cyrix"),
                        DMI_MATCH(DMI_PRODUCT_NAME, "Caddis"),
                },
        },
        { }
};

static int cs5530_is_palmax(void)
{
        if (dmi_check_system(palmax_dmi_table)) {
                printk(KERN_INFO "Palmax PD1100: Disabling DMA on docking port.\n");
                return 1;
        }
        return 0;
}


/**
 *      cs5530_init_chip        -       Chipset init
 *
 *      Perform the chip initialisation work that is shared between both
 *      setup and resume paths
 */

static int cs5530_init_chip(void)
{
        struct pci_dev *master_0 = NULL, *cs5530_0 = NULL, *dev = NULL;

        while ((dev = pci_get_device(PCI_VENDOR_ID_CYRIX, PCI_ANY_ID, dev)) != NULL) {
                switch (dev->device) {
                        case PCI_DEVICE_ID_CYRIX_PCI_MASTER:
                                master_0 = pci_dev_get(dev);
                                break;
                        case PCI_DEVICE_ID_CYRIX_5530_LEGACY:
                                cs5530_0 = pci_dev_get(dev);
                                break;
                }
        }
        if (!master_0) {
                printk(KERN_ERR DRV_NAME ": unable to locate PCI MASTER function\n");
                goto fail_put;
        }
        if (!cs5530_0) {
                printk(KERN_ERR DRV_NAME ": unable to locate CS5530 LEGACY function\n");
                goto fail_put;
        }

        pci_set_master(cs5530_0);
        pci_try_set_mwi(cs5530_0);

        /*
         * Set PCI CacheLineSize to 16-bytes:
         * --> Write 0x04 into 8-bit PCI CACHELINESIZE reg of function 0 of the cs5530
         *
         * Note: This value is constant because the 5530 is only a Geode companion
         */

        pci_write_config_byte(cs5530_0, PCI_CACHE_LINE_SIZE, 0x04);

        /*
         * Disable trapping of UDMA register accesses (Win98 hack):
         * --> Write 0x5006 into 16-bit reg at offset 0xd0 of function 0 of the cs5530
         */

        pci_write_config_word(cs5530_0, 0xd0, 0x5006);

        /*
         * Bit-1 at 0x40 enables MemoryWriteAndInvalidate on internal X-bus:
         * The other settings are what is necessary to get the register
         * into a sane state for IDE DMA operation.
         */

        pci_write_config_byte(master_0, 0x40, 0x1e);

        /*
         * Set max PCI burst size (16-bytes seems to work best):
         *         16bytes: set bit-1 at 0x41 (reg value of 0x16)
         *      all others: clear bit-1 at 0x41, and do:
         *        128bytes: OR 0x00 at 0x41
         *        256bytes: OR 0x04 at 0x41
         *        512bytes: OR 0x08 at 0x41
         *       1024bytes: OR 0x0c at 0x41
         */

        pci_write_config_byte(master_0, 0x41, 0x14);

        /*
         * These settings are necessary to get the chip
         * into a sane state for IDE DMA operation.
         */

        pci_write_config_byte(master_0, 0x42, 0x00);
        pci_write_config_byte(master_0, 0x43, 0xc1);

        pci_dev_put(master_0);
        pci_dev_put(cs5530_0);
        return 0;
fail_put:
        if (master_0)
                pci_dev_put(master_0);
        if (cs5530_0)
                pci_dev_put(cs5530_0);
        return -ENODEV;
}

/**
 *      cs5530_init_one         -       Initialise a CS5530
 *      @dev: PCI device
 *      @id: Entry in match table
 *
 *      Install a driver for the newly found CS5530 companion chip. Most of
 *      this is just housekeeping. We have to set the chip up correctly and
 *      turn off various bits of emulation magic.
 */

static int cs5530_init_one(struct pci_dev *pdev, const struct pci_device_id *id)
{
        static const struct ata_port_info info = {
                .flags = ATA_FLAG_SLAVE_POSS,
                .pio_mask = ATA_PIO4,
                .mwdma_mask = ATA_MWDMA2,
                .udma_mask = ATA_UDMA2,
                .port_ops = &cs5530_port_ops
        };
        /* The docking connector doesn't do UDMA, and it seems not MWDMA */
        static const struct ata_port_info info_palmax_secondary = {
                .flags = ATA_FLAG_SLAVE_POSS,
                .pio_mask = ATA_PIO4,
                .port_ops = &cs5530_port_ops
        };
        const struct ata_port_info *ppi[] = { &info, NULL };
        int rc;

        rc = pcim_enable_device(pdev);
        if (rc)
                return rc;

        /* Chip initialisation */
        if (cs5530_init_chip())
                return -ENODEV;

        if (cs5530_is_palmax())
                ppi[1] = &info_palmax_secondary;

        /* Now kick off ATA set up */
        return ata_pci_sff_init_one(pdev, ppi, &cs5530_sht, NULL);
}

#ifdef CONFIG_PM
static int cs5530_reinit_one(struct pci_dev *pdev)
{
        struct ata_host *host = dev_get_drvdata(&pdev->dev);
        int rc;

        rc = ata_pci_device_do_resume(pdev);
        if (rc)
                return rc;

        /* If we fail on resume we are doomed */
        if (cs5530_init_chip())
                return -EIO;

        ata_host_resume(host);
        return 0;
}
#endif /* CONFIG_PM */

static const struct pci_device_id cs5530[] = {
        { PCI_VDEVICE(CYRIX, PCI_DEVICE_ID_CYRIX_5530_IDE), },

        { },
};

static struct pci_driver cs5530_pci_driver = {
        .name           = DRV_NAME,
        .id_table       = cs5530,
        .probe          = cs5530_init_one,
        .remove         = ata_pci_remove_one,
#ifdef CONFIG_PM
        .suspend        = ata_pci_device_suspend,
        .resume         = cs5530_reinit_one,
#endif
};

static int __init cs5530_init(void)
{
        return pci_register_driver(&cs5530_pci_driver);
}

static void __exit cs5530_exit(void)
{
        pci_unregister_driver(&cs5530_pci_driver);
}

MODULE_AUTHOR("Alan Cox");
MODULE_DESCRIPTION("low-level driver for the Cyrix/NS/AMD 5530");
MODULE_LICENSE("GPL");
MODULE_DEVICE_TABLE(pci, cs5530);
MODULE_VERSION(DRV_VERSION);

module_init(cs5530_init);
module_exit(cs5530_exit);