/*
 * pata_ali.c   - ALI 15x3 PATA for new ATA layer
 *                        (C) 2005 Red Hat Inc
 *
 * based in part upon
 * linux/drivers/ide/pci/alim15x3.c             Version 0.17    2003/01/02
 *
 *  Copyright (C) 1998-2000 Michel Aubry, Maintainer
 *  Copyright (C) 1998-2000 Andrzej Krzysztofowicz, Maintainer
 *  Copyright (C) 1999-2000 CJ, cjtsai@ali.com.tw, Maintainer
 *
 *  Copyright (C) 1998-2000 Andre Hedrick (andre@linux-ide.org)
 *  May be copied or modified under the terms of the GNU General Public License
 *  Copyright (C) 2002 Alan Cox <alan@redhat.com>
 *  ALi (now ULi M5228) support by Clear Zhang <Clear.Zhang@ali.com.tw>
 *
 *  Documentation
 *      Chipset documentation available under NDA only
 *
 *  TODO/CHECK
 *      Cannot have ATAPI on both master & slave for rev < c2 (???) but
 *      otherwise should do atapi DMA (For now for old we do PIO only for
 *      ATAPI)
 *      Review Sunblade workaround.
 */

#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_ali"
#define DRV_VERSION "0.7.8"

static int ali_atapi_dma = 0;
module_param_named(atapi_dma, ali_atapi_dma, int, 0644);
MODULE_PARM_DESC(atapi_dma, "Enable ATAPI DMA (0=disable, 1=enable)");

static struct pci_dev *ali_isa_bridge;

/*
 *      Cable special cases
 */

static const struct dmi_system_id cable_dmi_table[] = {
        {
                .ident = "HP Pavilion N5430",
                .matches = {
                        DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
                        DMI_MATCH(DMI_BOARD_VERSION, "OmniBook N32N-736"),
                },
        },
        {
                .ident = "Toshiba Satellite S1800-814",
                .matches = {
                        DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
                        DMI_MATCH(DMI_PRODUCT_NAME, "S1800-814"),
                },
        },
        { }
};

static int ali_cable_override(struct pci_dev *pdev)
{
        /* Fujitsu P2000 */
        if (pdev->subsystem_vendor == 0x10CF && pdev->subsystem_device == 0x10AF)
                return 1;
        /* Mitac 8317 (Winbook-A) and relatives */
        if (pdev->subsystem_vendor == 0x1071 && pdev->subsystem_device == 0x8317)
                return 1;
        /* Systems by DMI */
        if (dmi_check_system(cable_dmi_table))
                return 1;
        return 0;
}

/**
 *      ali_c2_cable_detect     -       cable detection
 *      @ap: ATA port
 *
 *      Perform cable detection for C2 and later revisions
 */

static int ali_c2_cable_detect(struct ata_port *ap)
{
        struct pci_dev *pdev = to_pci_dev(ap->host->dev);
        u8 ata66;

        /* Certain laptops use short but suitable cables and don't
           implement the detect logic */

        if (ali_cable_override(pdev))
                return ATA_CBL_PATA40_SHORT;

        /* Host view cable detect 0x4A bit 0 primary bit 1 secondary
           Bit set for 40 pin */
        pci_read_config_byte(pdev, 0x4A, &ata66);
        if (ata66 & (1 << ap->port_no))
                return ATA_CBL_PATA40;
        else
                return ATA_CBL_PATA80;
}

/**
 *      ali_20_filter           -       filter for earlier ALI DMA
 *      @ap: ALi ATA port
 *      @adev: attached device
 *
 *      Ensure that we do not do DMA on CD devices. We may be able to
 *      fix that later on. Also ensure we do not do UDMA on WDC drives
 */

static unsigned long ali_20_filter(struct ata_device *adev, unsigned long mask)
{
        char model_num[ATA_ID_PROD_LEN + 1];
        /* No DMA on anything but a disk for now */
        if (adev->class != ATA_DEV_ATA)
                mask &= ~(ATA_MASK_MWDMA | ATA_MASK_UDMA);
        ata_id_c_string(adev->id, model_num, ATA_ID_PROD, sizeof(model_num));
        if (strstr(model_num, "WDC"))
                return mask &= ~ATA_MASK_UDMA;
        return mask;
}

/**
 *      ali_fifo_control        -       FIFO manager
 *      @ap: ALi channel to control
 *      @adev: device for FIFO control
 *      @on: 0 for off 1 for on
 *
 *      Enable or disable the FIFO on a given device. Because of the way the
 *      ALi FIFO works it provides a boost on ATA disk but can be confused by
 *      ATAPI and we must therefore manage it.
 */

static void ali_fifo_control(struct ata_port *ap, struct ata_device *adev, int on)
{
        struct pci_dev *pdev = to_pci_dev(ap->host->dev);
        int pio_fifo = 0x54 + ap->port_no;
        u8 fifo;
        int shift = 4 * adev->devno;

        /* ATA - FIFO on set nibble to 0x05, ATAPI - FIFO off, set nibble to
           0x00. Not all the docs agree but the behaviour we now use is the
           one stated in the BIOS Programming Guide */

        pci_read_config_byte(pdev, pio_fifo, &fifo);
        fifo &= ~(0x0F << shift);
        fifo |= (on << shift);
        pci_write_config_byte(pdev, pio_fifo, fifo);
}

/**
 *      ali_program_modes       -       load mode registers
 *      @ap: ALi channel to load
 *      @adev: Device the timing is for
 *      @t: timing data
 *      @ultra: UDMA timing or zero for off
 *
 *      Loads the timing registers for cmd/data and disable UDMA if
 *      ultra is zero. If ultra is set then load and enable the UDMA
 *      timing but do not touch the command/data timing.
 */

static void ali_program_modes(struct ata_port *ap, struct ata_device *adev, struct ata_timing *t, u8 ultra)
{
        struct pci_dev *pdev = to_pci_dev(ap->host->dev);
        int cas = 0x58 + 4 * ap->port_no;       /* Command timing */
        int cbt = 0x59 + 4 * ap->port_no;       /* Command timing */
        int drwt = 0x5A + 4 * ap->port_no + adev->devno; /* R/W timing */
        int udmat = 0x56 + ap->port_no; /* UDMA timing */
        int shift = 4 * adev->devno;
        u8 udma;

        if (t != NULL) {
                t->setup = clamp_val(t->setup, 1, 8) & 7;
                t->act8b = clamp_val(t->act8b, 1, 8) & 7;
                t->rec8b = clamp_val(t->rec8b, 1, 16) & 15;
                t->active = clamp_val(t->active, 1, 8) & 7;
                t->recover = clamp_val(t->recover, 1, 16) & 15;

                pci_write_config_byte(pdev, cas, t->setup);
                pci_write_config_byte(pdev, cbt, (t->act8b << 4) | t->rec8b);
                pci_write_config_byte(pdev, drwt, (t->active << 4) | t->recover);
        }

        /* Set up the UDMA enable */
        pci_read_config_byte(pdev, udmat, &udma);
        udma &= ~(0x0F << shift);
        udma |= ultra << shift;
        pci_write_config_byte(pdev, udmat, udma);
}

/**
 *      ali_set_piomode -       set initial PIO mode data
 *      @ap: ATA interface
 *      @adev: ATA device
 *
 *      Program the ALi registers for PIO mode.
 */

static void ali_set_piomode(struct ata_port *ap, struct ata_device *adev)
{
        struct ata_device *pair = ata_dev_pair(adev);
        struct ata_timing t;
        unsigned long T =  1000000000 / 33333;  /* PCI clock based */

        ata_timing_compute(adev, adev->pio_mode, &t, T, 1);
        if (pair) {
                struct ata_timing p;
                ata_timing_compute(pair, pair->pio_mode, &p, T, 1);
                ata_timing_merge(&p, &t, &t, ATA_TIMING_SETUP|ATA_TIMING_8BIT);
                if (pair->dma_mode) {
                        ata_timing_compute(pair, pair->dma_mode, &p, T, 1);
                        ata_timing_merge(&p, &t, &t, ATA_TIMING_SETUP|ATA_TIMING_8BIT);
                }
        }

        /* PIO FIFO is only permitted on ATA disk */
        if (adev->class != ATA_DEV_ATA)
                ali_fifo_control(ap, adev, 0x00);
        ali_program_modes(ap, adev, &t, 0);
        if (adev->class == ATA_DEV_ATA)
                ali_fifo_control(ap, adev, 0x05);

}

/**
 *      ali_set_dmamode -       set initial DMA mode data
 *      @ap: ATA interface
 *      @adev: ATA device
 *
 *      Program the ALi registers for DMA mode.
 */

static void ali_set_dmamode(struct ata_port *ap, struct ata_device *adev)
{
        static u8 udma_timing[7] = { 0xC, 0xB, 0xA, 0x9, 0x8, 0xF, 0xD };
        struct ata_device *pair = ata_dev_pair(adev);
        struct ata_timing t;
        unsigned long T =  1000000000 / 33333;  /* PCI clock based */
        struct pci_dev *pdev = to_pci_dev(ap->host->dev);


        if (adev->class == ATA_DEV_ATA)
                ali_fifo_control(ap, adev, 0x08);

        if (adev->dma_mode >= XFER_UDMA_0) {
                ali_program_modes(ap, adev, NULL, udma_timing[adev->dma_mode - XFER_UDMA_0]);
                if (adev->dma_mode >= XFER_UDMA_3) {
                        u8 reg4b;
                        pci_read_config_byte(pdev, 0x4B, &reg4b);
                        reg4b |= 1;
                        pci_write_config_byte(pdev, 0x4B, reg4b);
                }
        } else {
                ata_timing_compute(adev, adev->dma_mode, &t, T, 1);
                if (pair) {
                        struct ata_timing p;
                        ata_timing_compute(pair, pair->pio_mode, &p, T, 1);
                        ata_timing_merge(&p, &t, &t, ATA_TIMING_SETUP|ATA_TIMING_8BIT);
                        if (pair->dma_mode) {
                                ata_timing_compute(pair, pair->dma_mode, &p, T, 1);
                                ata_timing_merge(&p, &t, &t, ATA_TIMING_SETUP|ATA_TIMING_8BIT);
                        }
                }
                ali_program_modes(ap, adev, &t, 0);
        }
}

/**
 *      ali_warn_atapi_dma      -       Warn about ATAPI DMA disablement
 *      @adev: Device
 *
 *      Whine about ATAPI DMA disablement if @adev is an ATAPI device.
 *      Can be used as ->dev_config.
 */

static void ali_warn_atapi_dma(struct ata_device *adev)
{
        struct ata_eh_context *ehc = &adev->link->eh_context;
        int print_info = ehc->i.flags & ATA_EHI_PRINTINFO;

        if (print_info && adev->class == ATA_DEV_ATAPI && !ali_atapi_dma) {
                ata_dev_warn(adev,
                             "WARNING: ATAPI DMA disabled for reliability issues.  It can be enabled\n");
                ata_dev_warn(adev,
                             "WARNING: via pata_ali.atapi_dma modparam or corresponding sysfs node.\n");
        }
}

/**
 *      ali_lock_sectors        -       Keep older devices to 255 sector mode
 *      @adev: Device
 *
 *      Called during the bus probe for each device that is found. We use
 *      this call to lock the sector count of the device to 255 or less on
 *      older ALi controllers. If we didn't do this then large I/O's would
 *      require LBA48 commands which the older ALi requires are issued by
 *      slower PIO methods
 */

static void ali_lock_sectors(struct ata_device *adev)
{
        adev->max_sectors = 255;
        ali_warn_atapi_dma(adev);
}

/**
 *      ali_check_atapi_dma     -       DMA check for most ALi controllers
 *      @adev: Device
 *
 *      Called to decide whether commands should be sent by DMA or PIO
 */

static int ali_check_atapi_dma(struct ata_queued_cmd *qc)
{
        if (!ali_atapi_dma) {
                /* FIXME: pata_ali can't do ATAPI DMA reliably but the
                 * IDE alim15x3 driver can.  I tried lots of things
                 * but couldn't find what the actual difference was.
                 * If you got an idea, please write it to
                 * linux-ide@vger.kernel.org and cc htejun@gmail.com.
                 *
                 * Disable ATAPI DMA for now.
                 */
                return -EOPNOTSUPP;
        }

        /* If its not a media command, its not worth it */
        if (atapi_cmd_type(qc->cdb[0]) == ATAPI_MISC)
                return -EOPNOTSUPP;
        return 0;
}

static void ali_c2_c3_postreset(struct ata_link *link, unsigned int *classes)
{
        u8 r;
        int port_bit = 4 << link->ap->port_no;

        /* If our bridge is an ALI 1533 then do the extra work */
        if (ali_isa_bridge) {
                /* Tristate and re-enable the bus signals */
                pci_read_config_byte(ali_isa_bridge, 0x58, &r);
                r &= ~port_bit;
                pci_write_config_byte(ali_isa_bridge, 0x58, r);
                r |= port_bit;
                pci_write_config_byte(ali_isa_bridge, 0x58, r);
        }
        ata_sff_postreset(link, classes);
}

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

/*
 *      Port operations for PIO only ALi
 */

static struct ata_port_operations ali_early_port_ops = {
        .inherits       = &ata_sff_port_ops,
        .cable_detect   = ata_cable_40wire,
        .set_piomode    = ali_set_piomode,
        .sff_data_xfer  = ata_sff_data_xfer32,
};

static const struct ata_port_operations ali_dma_base_ops = {
        .inherits       = &ata_bmdma32_port_ops,
        .set_piomode    = ali_set_piomode,
        .set_dmamode    = ali_set_dmamode,
};

/*
 *      Port operations for DMA capable ALi without cable
 *      detect
 */
static struct ata_port_operations ali_20_port_ops = {
        .inherits       = &ali_dma_base_ops,
        .cable_detect   = ata_cable_40wire,
        .mode_filter    = ali_20_filter,
        .check_atapi_dma = ali_check_atapi_dma,
        .dev_config     = ali_lock_sectors,
};

/*
 *      Port operations for DMA capable ALi with cable detect
 */
static struct ata_port_operations ali_c2_port_ops = {
        .inherits       = &ali_dma_base_ops,
        .check_atapi_dma = ali_check_atapi_dma,
        .cable_detect   = ali_c2_cable_detect,
        .dev_config     = ali_lock_sectors,
        .postreset      = ali_c2_c3_postreset,
};

/*
 *      Port operations for DMA capable ALi with cable detect
 */
static struct ata_port_operations ali_c4_port_ops = {
        .inherits       = &ali_dma_base_ops,
        .check_atapi_dma = ali_check_atapi_dma,
        .cable_detect   = ali_c2_cable_detect,
        .dev_config     = ali_lock_sectors,
};

/*
 *      Port operations for DMA capable ALi with cable detect and LBA48
 */
static struct ata_port_operations ali_c5_port_ops = {
        .inherits       = &ali_dma_base_ops,
        .check_atapi_dma = ali_check_atapi_dma,
        .dev_config     = ali_warn_atapi_dma,
        .cable_detect   = ali_c2_cable_detect,
};


/**
 *      ali_init_chipset        -       chip setup function
 *      @pdev: PCI device of ATA controller
 *
 *      Perform the setup on the device that must be done both at boot
 *      and at resume time.
 */

static void ali_init_chipset(struct pci_dev *pdev)
{
        u8 tmp;
        struct pci_dev *north;

        /*
         * The chipset revision selects the driver operations and
         * mode data.
         */

        if (pdev->revision <= 0x20) {
                pci_read_config_byte(pdev, 0x53, &tmp);
                tmp |= 0x03;
                pci_write_config_byte(pdev, 0x53, tmp);
        } else {
                pci_read_config_byte(pdev, 0x4a, &tmp);
                pci_write_config_byte(pdev, 0x4a, tmp | 0x20);
                pci_read_config_byte(pdev, 0x4B, &tmp);
                if (pdev->revision < 0xC2)
                        /* 1543-E/F, 1543C-C, 1543C-D, 1543C-E */
                        /* Clear CD-ROM DMA write bit */
                        tmp &= 0x7F;
                /* Cable and UDMA */
                if (pdev->revision >= 0xc2)
                        tmp |= 0x01;
                pci_write_config_byte(pdev, 0x4B, tmp | 0x08);
                /*
                 * CD_ROM DMA on (0x53 bit 0). Enable this even if we want
                 * to use PIO. 0x53 bit 1 (rev 20 only) - enable FIFO control
                 * via 0x54/55.
                 */
                pci_read_config_byte(pdev, 0x53, &tmp);
                if (pdev->revision >= 0xc7)
                        tmp |= 0x03;
                else
                        tmp |= 0x01;    /* CD_ROM enable for DMA */
                pci_write_config_byte(pdev, 0x53, tmp);
        }
        north = pci_get_bus_and_slot(0, PCI_DEVFN(0,0));
        if (north && north->vendor == PCI_VENDOR_ID_AL && ali_isa_bridge) {
                /* Configure the ALi bridge logic. For non ALi rely on BIOS.
                   Set the south bridge enable bit */
                pci_read_config_byte(ali_isa_bridge, 0x79, &tmp);
                if (pdev->revision == 0xC2)
                        pci_write_config_byte(ali_isa_bridge, 0x79, tmp | 0x04);
                else if (pdev->revision > 0xC2 && pdev->revision < 0xC5)
                        pci_write_config_byte(ali_isa_bridge, 0x79, tmp | 0x02);
        }
        pci_dev_put(north);
        ata_pci_bmdma_clear_simplex(pdev);
}
/**
 *      ali_init_one            -       discovery callback
 *      @pdev: PCI device ID
 *      @id: PCI table info
 *
 *      An ALi IDE interface has been discovered. Figure out what revision
 *      and perform configuration work before handing it to the ATA layer
 */

static int ali_init_one(struct pci_dev *pdev, const struct pci_device_id *id)
{
        static const struct ata_port_info info_early = {
                .flags = ATA_FLAG_SLAVE_POSS,
                .pio_mask = ATA_PIO4,
                .port_ops = &ali_early_port_ops
        };
        /* Revision 0x20 added DMA */
        static const struct ata_port_info info_20 = {
                .flags = ATA_FLAG_SLAVE_POSS | ATA_FLAG_PIO_LBA48 |
                                                        ATA_FLAG_IGN_SIMPLEX,
                .pio_mask = ATA_PIO4,
                .mwdma_mask = ATA_MWDMA2,
                .port_ops = &ali_20_port_ops
        };
        /* Revision 0x20 with support logic added UDMA */
        static const struct ata_port_info info_20_udma = {
                .flags = ATA_FLAG_SLAVE_POSS | ATA_FLAG_PIO_LBA48 |
                                                        ATA_FLAG_IGN_SIMPLEX,
                .pio_mask = ATA_PIO4,
                .mwdma_mask = ATA_MWDMA2,
                .udma_mask = ATA_UDMA2,
                .port_ops = &ali_20_port_ops
        };
        /* Revision 0xC2 adds UDMA66 */
        static const struct ata_port_info info_c2 = {
                .flags = ATA_FLAG_SLAVE_POSS | ATA_FLAG_PIO_LBA48 |
                                                        ATA_FLAG_IGN_SIMPLEX,
                .pio_mask = ATA_PIO4,
                .mwdma_mask = ATA_MWDMA2,
                .udma_mask = ATA_UDMA4,
                .port_ops = &ali_c2_port_ops
        };
        /* Revision 0xC3 is UDMA66 for now */
        static const struct ata_port_info info_c3 = {
                .flags = ATA_FLAG_SLAVE_POSS | ATA_FLAG_PIO_LBA48 |
                                                        ATA_FLAG_IGN_SIMPLEX,
                .pio_mask = ATA_PIO4,
                .mwdma_mask = ATA_MWDMA2,
                .udma_mask = ATA_UDMA4,
                .port_ops = &ali_c2_port_ops
        };
        /* Revision 0xC4 is UDMA100 */
        static const struct ata_port_info info_c4 = {
                .flags = ATA_FLAG_SLAVE_POSS | ATA_FLAG_PIO_LBA48 |
                                                        ATA_FLAG_IGN_SIMPLEX,
                .pio_mask = ATA_PIO4,
                .mwdma_mask = ATA_MWDMA2,
                .udma_mask = ATA_UDMA5,
                .port_ops = &ali_c4_port_ops
        };
        /* Revision 0xC5 is UDMA133 with LBA48 DMA */
        static const struct ata_port_info info_c5 = {
                .flags = ATA_FLAG_SLAVE_POSS |  ATA_FLAG_IGN_SIMPLEX,
                .pio_mask = ATA_PIO4,
                .mwdma_mask = ATA_MWDMA2,
                .udma_mask = ATA_UDMA6,
                .port_ops = &ali_c5_port_ops
        };

        const struct ata_port_info *ppi[] = { NULL, NULL };
        u8 tmp;
        int rc;

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

        /*
         * The chipset revision selects the driver operations and
         * mode data.
         */

        if (pdev->revision < 0x20) {
                ppi[0] = &info_early;
        } else if (pdev->revision < 0xC2) {
                ppi[0] = &info_20;
        } else if (pdev->revision == 0xC2) {
                ppi[0] = &info_c2;
        } else if (pdev->revision == 0xC3) {
                ppi[0] = &info_c3;
        } else if (pdev->revision == 0xC4) {
                ppi[0] = &info_c4;
        } else
                ppi[0] = &info_c5;

        ali_init_chipset(pdev);

        if (ali_isa_bridge && pdev->revision >= 0x20 && pdev->revision < 0xC2) {
                /* Are we paired with a UDMA capable chip */
                pci_read_config_byte(ali_isa_bridge, 0x5E, &tmp);
                if ((tmp & 0x1E) == 0x12)
                        ppi[0] = &info_20_udma;
        }

        if (!ppi[0]->mwdma_mask && !ppi[0]->udma_mask)
                return ata_pci_sff_init_one(pdev, ppi, &ali_sht, NULL, 0);
        else
                return ata_pci_bmdma_init_one(pdev, ppi, &ali_sht, NULL, 0);
}

#ifdef CONFIG_PM
static int ali_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;
        ali_init_chipset(pdev);
        ata_host_resume(host);
        return 0;
}
#endif

static const struct pci_device_id ali[] = {
        { PCI_VDEVICE(AL, PCI_DEVICE_ID_AL_M5228), },
        { PCI_VDEVICE(AL, PCI_DEVICE_ID_AL_M5229), },

        { },
};

static struct pci_driver ali_pci_driver = {
        .name           = DRV_NAME,
        .id_table       = ali,
        .probe          = ali_init_one,
        .remove         = ata_pci_remove_one,
#ifdef CONFIG_PM
        .suspend        = ata_pci_device_suspend,
        .resume         = ali_reinit_one,
#endif
};

static int __init ali_init(void)
{
        int ret;
        ali_isa_bridge = pci_get_device(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M1533, NULL);

        ret = pci_register_driver(&ali_pci_driver);
        if (ret < 0)
                pci_dev_put(ali_isa_bridge);
        return ret;
}


static void __exit ali_exit(void)
{
        pci_unregister_driver(&ali_pci_driver);
        pci_dev_put(ali_isa_bridge);
}


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

module_init(ali_init);
module_exit(ali_exit);