/*
 *    pata_artop.c - ARTOP ATA controller driver
 *
 *      (C) 2006 Red Hat
 *      (C) 2007 Bartlomiej Zolnierkiewicz
 *
 *    Based in part on drivers/ide/pci/aec62xx.c
 *      Copyright (C) 1999-2002 Andre Hedrick <andre@linux-ide.org>
 *      865/865R fixes for Macintosh card version from a patch to the old
 *              driver by Thibaut VARENE <varenet@parisc-linux.org>
 *      When setting the PCI latency we must set 0x80 or higher for burst
 *              performance Alessandro Zummo <alessandro.zummo@towertech.it>
 *
 *      TODO
 *      Investigate no_dsc on 850R
 *      Clock detect
 */

#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 <linux/device.h>
#include <scsi/scsi_host.h>
#include <linux/libata.h>
#include <linux/ata.h>

#define DRV_NAME        "pata_artop"
#define DRV_VERSION     "0.4.5"

/*
 *      The ARTOP has 33 Mhz and "over clocked" timing tables. Until we
 *      get PCI bus speed functionality we leave this as 0. Its a variable
 *      for when we get the functionality and also for folks wanting to
 *      test stuff.
 */

static int clock = 0;

static int artop6210_pre_reset(struct ata_link *link, unsigned long deadline)
{
        struct ata_port *ap = link->ap;
        struct pci_dev *pdev = to_pci_dev(ap->host->dev);
        const struct pci_bits artop_enable_bits[] = {
                { 0x4AU, 1U, 0x02UL, 0x02UL },  /* port 0 */
                { 0x4AU, 1U, 0x04UL, 0x04UL },  /* port 1 */
        };

        if (!pci_test_config_bits(pdev, &artop_enable_bits[ap->port_no]))
                return -ENOENT;

        return ata_sff_prereset(link, deadline);
}

/**
 *      artop6260_pre_reset     -       check for 40/80 pin
 *      @link: link
 *      @deadline: deadline jiffies for the operation
 *
 *      The ARTOP hardware reports the cable detect bits in register 0x49.
 *      Nothing complicated needed here.
 */

static int artop6260_pre_reset(struct ata_link *link, unsigned long deadline)
{
        static const struct pci_bits artop_enable_bits[] = {
                { 0x4AU, 1U, 0x02UL, 0x02UL },  /* port 0 */
                { 0x4AU, 1U, 0x04UL, 0x04UL },  /* port 1 */
        };

        struct ata_port *ap = link->ap;
        struct pci_dev *pdev = to_pci_dev(ap->host->dev);

        /* Odd numbered device ids are the units with enable bits (the -R cards) */
        if ((pdev->device & 1) &&
            !pci_test_config_bits(pdev, &artop_enable_bits[ap->port_no]))
                return -ENOENT;

        return ata_sff_prereset(link, deadline);
}

/**
 *      artop6260_cable_detect  -       identify cable type
 *      @ap: Port
 *
 *      Identify the cable type for the ARTOP interface in question
 */

static int artop6260_cable_detect(struct ata_port *ap)
{
        struct pci_dev *pdev = to_pci_dev(ap->host->dev);
        u8 tmp;
        pci_read_config_byte(pdev, 0x49, &tmp);
        if (tmp & (1 << ap->port_no))
                return ATA_CBL_PATA40;
        return ATA_CBL_PATA80;
}

/**
 *      artop6210_load_piomode - Load a set of PATA PIO timings
 *      @ap: Port whose timings we are configuring
 *      @adev: Device
 *      @pio: PIO mode
 *
 *      Set PIO mode for device, in host controller PCI config space. This
 *      is used both to set PIO timings in PIO mode and also to set the
 *      matching PIO clocking for UDMA, as well as the MWDMA timings.
 *
 *      LOCKING:
 *      None (inherited from caller).
 */

static void artop6210_load_piomode(struct ata_port *ap, struct ata_device *adev, unsigned int pio)
{
        struct pci_dev *pdev    = to_pci_dev(ap->host->dev);
        int dn = adev->devno + 2 * ap->port_no;
        const u16 timing[2][5] = {
                { 0x0000, 0x000A, 0x0008, 0x0303, 0x0301 },
                { 0x0700, 0x070A, 0x0708, 0x0403, 0x0401 }

        };
        /* Load the PIO timing active/recovery bits */
        pci_write_config_word(pdev, 0x40 + 2 * dn, timing[clock][pio]);
}

/**
 *      artop6210_set_piomode - Initialize host controller PATA PIO timings
 *      @ap: Port whose timings we are configuring
 *      @adev: Device we are configuring
 *
 *      Set PIO mode for device, in host controller PCI config space. For
 *      ARTOP we must also clear the UDMA bits if we are not doing UDMA. In
 *      the event UDMA is used the later call to set_dmamode will set the
 *      bits as required.
 *
 *      LOCKING:
 *      None (inherited from caller).
 */

static void artop6210_set_piomode(struct ata_port *ap, struct ata_device *adev)
{
        struct pci_dev *pdev    = to_pci_dev(ap->host->dev);
        int dn = adev->devno + 2 * ap->port_no;
        u8 ultra;

        artop6210_load_piomode(ap, adev, adev->pio_mode - XFER_PIO_0);

        /* Clear the UDMA mode bits (set_dmamode will redo this if needed) */
        pci_read_config_byte(pdev, 0x54, &ultra);
        ultra &= ~(3 << (2 * dn));
        pci_write_config_byte(pdev, 0x54, ultra);
}

/**
 *      artop6260_load_piomode - Initialize host controller PATA PIO timings
 *      @ap: Port whose timings we are configuring
 *      @adev: Device we are configuring
 *      @pio: PIO mode
 *
 *      Set PIO mode for device, in host controller PCI config space. The
 *      ARTOP6260 and relatives store the timing data differently.
 *
 *      LOCKING:
 *      None (inherited from caller).
 */

static void artop6260_load_piomode (struct ata_port *ap, struct ata_device *adev, unsigned int pio)
{
        struct pci_dev *pdev    = to_pci_dev(ap->host->dev);
        int dn = adev->devno + 2 * ap->port_no;
        const u8 timing[2][5] = {
                { 0x00, 0x0A, 0x08, 0x33, 0x31 },
                { 0x70, 0x7A, 0x78, 0x43, 0x41 }

        };
        /* Load the PIO timing active/recovery bits */
        pci_write_config_byte(pdev, 0x40 + dn, timing[clock][pio]);
}

/**
 *      artop6260_set_piomode - Initialize host controller PATA PIO timings
 *      @ap: Port whose timings we are configuring
 *      @adev: Device we are configuring
 *
 *      Set PIO mode for device, in host controller PCI config space. For
 *      ARTOP we must also clear the UDMA bits if we are not doing UDMA. In
 *      the event UDMA is used the later call to set_dmamode will set the
 *      bits as required.
 *
 *      LOCKING:
 *      None (inherited from caller).
 */

static void artop6260_set_piomode(struct ata_port *ap, struct ata_device *adev)
{
        struct pci_dev *pdev    = to_pci_dev(ap->host->dev);
        u8 ultra;

        artop6260_load_piomode(ap, adev, adev->pio_mode - XFER_PIO_0);

        /* Clear the UDMA mode bits (set_dmamode will redo this if needed) */
        pci_read_config_byte(pdev, 0x44 + ap->port_no, &ultra);
        ultra &= ~(7 << (4  * adev->devno));    /* One nibble per drive */
        pci_write_config_byte(pdev, 0x44 + ap->port_no, ultra);
}

/**
 *      artop6210_set_dmamode - Initialize host controller PATA PIO timings
 *      @ap: Port whose timings we are configuring
 *      @adev: Device whose timings we are configuring
 *
 *      Set DMA mode for device, in host controller PCI config space.
 *
 *      LOCKING:
 *      None (inherited from caller).
 */

static void artop6210_set_dmamode (struct ata_port *ap, struct ata_device *adev)
{
        unsigned int pio;
        struct pci_dev *pdev    = to_pci_dev(ap->host->dev);
        int dn = adev->devno + 2 * ap->port_no;
        u8 ultra;

        if (adev->dma_mode == XFER_MW_DMA_0)
                pio = 1;
        else
                pio = 4;

        /* Load the PIO timing active/recovery bits */
        artop6210_load_piomode(ap, adev, pio);

        pci_read_config_byte(pdev, 0x54, &ultra);
        ultra &= ~(3 << (2 * dn));

        /* Add ultra DMA bits if in UDMA mode */
        if (adev->dma_mode >= XFER_UDMA_0) {
                u8 mode = (adev->dma_mode - XFER_UDMA_0) + 1 - clock;
                if (mode == 0)
                        mode = 1;
                ultra |= (mode << (2 * dn));
        }
        pci_write_config_byte(pdev, 0x54, ultra);
}

/**
 *      artop6260_set_dmamode - Initialize host controller PATA PIO timings
 *      @ap: Port whose timings we are configuring
 *      @adev: Device we are configuring
 *
 *      Set DMA mode for device, in host controller PCI config space. The
 *      ARTOP6260 and relatives store the timing data differently.
 *
 *      LOCKING:
 *      None (inherited from caller).
 */

static void artop6260_set_dmamode (struct ata_port *ap, struct ata_device *adev)
{
        unsigned int pio        = adev->pio_mode - XFER_PIO_0;
        struct pci_dev *pdev    = to_pci_dev(ap->host->dev);
        u8 ultra;

        if (adev->dma_mode == XFER_MW_DMA_0)
                pio = 1;
        else
                pio = 4;

        /* Load the PIO timing active/recovery bits */
        artop6260_load_piomode(ap, adev, pio);

        /* Add ultra DMA bits if in UDMA mode */
        pci_read_config_byte(pdev, 0x44 + ap->port_no, &ultra);
        ultra &= ~(7 << (4  * adev->devno));    /* One nibble per drive */
        if (adev->dma_mode >= XFER_UDMA_0) {
                u8 mode = adev->dma_mode - XFER_UDMA_0 + 1 - clock;
                if (mode == 0)
                        mode = 1;
                ultra |= (mode << (4 * adev->devno));
        }
        pci_write_config_byte(pdev, 0x44 + ap->port_no, ultra);
}

/**
 *      artop_6210_qc_defer     -       implement serialization
 *      @qc: command
 *
 *      Issue commands per host on this chip.
 */

static int artop6210_qc_defer(struct ata_queued_cmd *qc)
{
        struct ata_host *host = qc->ap->host;
        struct ata_port *alt = host->ports[1 ^ qc->ap->port_no];
        int rc;

        /* First apply the usual rules */
        rc = ata_std_qc_defer(qc);
        if (rc != 0)
                return rc;

        /* Now apply serialization rules. Only allow a command if the
           other channel state machine is idle */
        if (alt && alt->qc_active)
                return  ATA_DEFER_PORT;
        return 0;
}

static struct scsi_host_template artop_sht = {
        ATA_BMDMA_SHT(DRV_NAME),
};

static struct ata_port_operations artop6210_ops = {
        .inherits               = &ata_bmdma_port_ops,
        .cable_detect           = ata_cable_40wire,
        .set_piomode            = artop6210_set_piomode,
        .set_dmamode            = artop6210_set_dmamode,
        .prereset               = artop6210_pre_reset,
        .qc_defer               = artop6210_qc_defer,
};

static struct ata_port_operations artop6260_ops = {
        .inherits               = &ata_bmdma_port_ops,
        .cable_detect           = artop6260_cable_detect,
        .set_piomode            = artop6260_set_piomode,
        .set_dmamode            = artop6260_set_dmamode,
        .prereset               = artop6260_pre_reset,
};


/**
 *      artop_init_one - Register ARTOP ATA PCI device with kernel services
 *      @pdev: PCI device to register
 *      @ent: Entry in artop_pci_tbl matching with @pdev
 *
 *      Called from kernel PCI layer.
 *
 *      LOCKING:
 *      Inherited from PCI layer (may sleep).
 *
 *      RETURNS:
 *      Zero on success, or -ERRNO value.
 */

static int artop_init_one (struct pci_dev *pdev, const struct pci_device_id *id)
{
        static int printed_version;
        static const struct ata_port_info info_6210 = {
                .flags          = ATA_FLAG_SLAVE_POSS,
                .pio_mask       = ATA_PIO4,
                .mwdma_mask     = ATA_MWDMA2,
                .udma_mask      = ATA_UDMA2,
                .port_ops       = &artop6210_ops,
        };
        static const struct ata_port_info info_626x = {
                .flags          = ATA_FLAG_SLAVE_POSS,
                .pio_mask       = ATA_PIO4,
                .mwdma_mask     = ATA_MWDMA2,
                .udma_mask      = ATA_UDMA4,
                .port_ops       = &artop6260_ops,
        };
        static const struct ata_port_info info_628x = {
                .flags          = ATA_FLAG_SLAVE_POSS,
                .pio_mask       = ATA_PIO4,
                .mwdma_mask     = ATA_MWDMA2,
                .udma_mask      = ATA_UDMA5,
                .port_ops       = &artop6260_ops,
        };
        static const struct ata_port_info info_628x_fast = {
                .flags          = ATA_FLAG_SLAVE_POSS,
                .pio_mask       = ATA_PIO4,
                .mwdma_mask     = ATA_MWDMA2,
                .udma_mask      = ATA_UDMA6,
                .port_ops       = &artop6260_ops,
        };
        const struct ata_port_info *ppi[] = { NULL, NULL };
        int rc;

        if (!printed_version++)
                dev_printk(KERN_DEBUG, &pdev->dev,
                           "version " DRV_VERSION "\n");

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

        if (id->driver_data == 0) {     /* 6210 variant */
                ppi[0] = &info_6210;
                /* BIOS may have left us in UDMA, clear it before libata probe */
                pci_write_config_byte(pdev, 0x54, 0);
        }
        else if (id->driver_data == 1)  /* 6260 */
                ppi[0] = &info_626x;
        else if (id->driver_data == 2)  { /* 6280 or 6280 + fast */
                unsigned long io = pci_resource_start(pdev, 4);
                u8 reg;

                ppi[0] = &info_628x;
                if (inb(io) & 0x10)
                        ppi[0] = &info_628x_fast;
                /* Mac systems come up with some registers not set as we
                   will need them */

                /* Clear reset & test bits */
                pci_read_config_byte(pdev, 0x49, &reg);
                pci_write_config_byte(pdev, 0x49, reg & ~ 0x30);

                /* PCI latency must be > 0x80 for burst mode, tweak it
                 * if required.
                 */
                pci_read_config_byte(pdev, PCI_LATENCY_TIMER, &reg);
                if (reg <= 0x80)
                        pci_write_config_byte(pdev, PCI_LATENCY_TIMER, 0x90);

                /* Enable IRQ output and burst mode */
                pci_read_config_byte(pdev, 0x4a, &reg);
                pci_write_config_byte(pdev, 0x4a, (reg & ~0x01) | 0x80);

        }

        BUG_ON(ppi[0] == NULL);

        return ata_pci_bmdma_init_one(pdev, ppi, &artop_sht, NULL, 0);
}

static const struct pci_device_id artop_pci_tbl[] = {
        { PCI_VDEVICE(ARTOP, 0x0005), 0 },
        { PCI_VDEVICE(ARTOP, 0x0006), 1 },
        { PCI_VDEVICE(ARTOP, 0x0007), 1 },
        { PCI_VDEVICE(ARTOP, 0x0008), 2 },
        { PCI_VDEVICE(ARTOP, 0x0009), 2 },

        { }     /* terminate list */
};

static struct pci_driver artop_pci_driver = {
        .name                   = DRV_NAME,
        .id_table               = artop_pci_tbl,
        .probe                  = artop_init_one,
        .remove                 = ata_pci_remove_one,
};

static int __init artop_init(void)
{
        return pci_register_driver(&artop_pci_driver);
}

static void __exit artop_exit(void)
{
        pci_unregister_driver(&artop_pci_driver);
}

module_init(artop_init);
module_exit(artop_exit);

MODULE_AUTHOR("Alan Cox");
MODULE_DESCRIPTION("SCSI low-level driver for ARTOP PATA");
MODULE_LICENSE("GPL");
MODULE_DEVICE_TABLE(pci, artop_pci_tbl);
MODULE_VERSION(DRV_VERSION);