/*
 *  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
 *  ALi (now ULi M5228) support by Clear Zhang <Clear.Zhang@ali.com.tw>
 *  Copyright (C) 2007 MontaVista Software, Inc. <source@mvista.com>
 *  Copyright (C) 2007 Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
 *
 *  (U)DMA capable version of ali 1533/1543(C), 1535(D)
 *
 **********************************************************************
 *  9/7/99 --Parts from the above author are included and need to be
 *  converted into standard interface, once I finish the thought.
 *
 *  Recent changes
 *      Don't use LBA48 mode on ALi <= 0xC4
 *      Don't poke 0x79 with a non ALi northbridge
 *      Don't flip undefined bits on newer chipsets (fix Fujitsu laptop hang)
 *      Allow UDMA6 on revisions > 0xC4
 *
 *  Documentation
 *      Chipset documentation available under NDA only
 *
 */

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

#include <asm/io.h>

#define DRV_NAME "alim15x3"

/*
 * Allow UDMA on M1543C-E chipset for WDC disks that ignore CRC checking
 * (this is DANGEROUS and could result in data corruption).
 */
static int wdc_udma;

module_param(wdc_udma, bool, 0);
MODULE_PARM_DESC(wdc_udma,
                 "allow UDMA on M1543C-E chipset for WDC disks (DANGEROUS)");

/*
 *      ALi devices are not plug in. Otherwise these static values would
 *      need to go. They ought to go away anyway
 */
 
static u8 m5229_revision;
static u8 chip_is_1543c_e;
static struct pci_dev *isa_dev;

/**
 *      ali_set_pio_mode        -       set host controller for PIO mode
 *      @drive: drive
 *      @pio: PIO mode number
 *
 *      Program the controller for the given PIO mode.
 */

static void ali_set_pio_mode(ide_drive_t *drive, const u8 pio)
{
        ide_hwif_t *hwif = drive->hwif;
        struct pci_dev *dev = to_pci_dev(hwif->dev);
        struct ide_timing *t = ide_timing_find_mode(XFER_PIO_0 + pio);
        int s_time = t->setup, a_time = t->active, c_time = t->cycle;
        u8 s_clc, a_clc, r_clc;
        unsigned long flags;
        int bus_speed = ide_pci_clk ? ide_pci_clk : 33;
        int port = hwif->channel ? 0x5c : 0x58;
        int portFIFO = hwif->channel ? 0x55 : 0x54;
        u8 cd_dma_fifo = 0, unit = drive->dn & 1;

        if ((s_clc = (s_time * bus_speed + 999) / 1000) >= 8)
                s_clc = 0;
        if ((a_clc = (a_time * bus_speed + 999) / 1000) >= 8)
                a_clc = 0;

        if (!(r_clc = (c_time * bus_speed + 999) / 1000 - a_clc - s_clc)) {
                r_clc = 1;
        } else {
                if (r_clc >= 16)
                        r_clc = 0;
        }
        local_irq_save(flags);
        
        /* 
         * PIO mode => ATA FIFO on, ATAPI FIFO off
         */
        pci_read_config_byte(dev, portFIFO, &cd_dma_fifo);
        if (drive->media==ide_disk) {
                if (unit) {
                        pci_write_config_byte(dev, portFIFO, (cd_dma_fifo & 0x0F) | 0x50);
                } else {
                        pci_write_config_byte(dev, portFIFO, (cd_dma_fifo & 0xF0) | 0x05);
                }
        } else {
                if (unit) {
                        pci_write_config_byte(dev, portFIFO, cd_dma_fifo & 0x0F);
                } else {
                        pci_write_config_byte(dev, portFIFO, cd_dma_fifo & 0xF0);
                }
        }
        
        pci_write_config_byte(dev, port, s_clc);
        pci_write_config_byte(dev, port + unit + 2, (a_clc << 4) | r_clc);
        local_irq_restore(flags);
}

/**
 *      ali_udma_filter         -       compute UDMA mask
 *      @drive: IDE device
 *
 *      Return available UDMA modes.
 *
 *      The actual rules for the ALi are:
 *              No UDMA on revisions <= 0x20
 *              Disk only for revisions < 0xC2
 *              Not WDC drives on M1543C-E (?)
 */

static u8 ali_udma_filter(ide_drive_t *drive)
{
        if (m5229_revision > 0x20 && m5229_revision < 0xC2) {
                if (drive->media != ide_disk)
                        return 0;
                if (wdc_udma == 0 && chip_is_1543c_e &&
                    strstr((char *)&drive->id[ATA_ID_PROD], "WDC "))
                        return 0;
        }

        return drive->hwif->ultra_mask;
}

/**
 *      ali_set_dma_mode        -       set host controller for DMA mode
 *      @drive: drive
 *      @speed: DMA mode
 *
 *      Configure the hardware for the desired IDE transfer mode.
 */

static void ali_set_dma_mode(ide_drive_t *drive, const u8 speed)
{
        ide_hwif_t *hwif        = drive->hwif;
        struct pci_dev *dev     = to_pci_dev(hwif->dev);
        u8 speed1               = speed;
        u8 unit                 = drive->dn & 1;
        u8 tmpbyte              = 0x00;
        int m5229_udma          = (hwif->channel) ? 0x57 : 0x56;

        if (speed == XFER_UDMA_6)
                speed1 = 0x47;

        if (speed < XFER_UDMA_0) {
                u8 ultra_enable = (unit) ? 0x7f : 0xf7;
                /*
                 * clear "ultra enable" bit
                 */
                pci_read_config_byte(dev, m5229_udma, &tmpbyte);
                tmpbyte &= ultra_enable;
                pci_write_config_byte(dev, m5229_udma, tmpbyte);

                /*
                 * FIXME: Oh, my... DMA timings are never set.
                 */
        } else {
                pci_read_config_byte(dev, m5229_udma, &tmpbyte);
                tmpbyte &= (0x0f << ((1-unit) << 2));
                /*
                 * enable ultra dma and set timing
                 */
                tmpbyte |= ((0x08 | ((4-speed1)&0x07)) << (unit << 2));
                pci_write_config_byte(dev, m5229_udma, tmpbyte);
                if (speed >= XFER_UDMA_3) {
                        pci_read_config_byte(dev, 0x4b, &tmpbyte);
                        tmpbyte |= 1;
                        pci_write_config_byte(dev, 0x4b, tmpbyte);
                }
        }
}

/**
 *      ali_dma_check   -       DMA check
 *      @drive: target device
 *      @cmd: command
 *
 *      Returns 1 if the DMA cannot be performed, zero on success.
 */

static int ali_dma_check(ide_drive_t *drive, struct ide_cmd *cmd)
{
        if (m5229_revision < 0xC2 && drive->media != ide_disk) {
                if (cmd->tf_flags & IDE_TFLAG_WRITE)
                        return 1;       /* try PIO instead of DMA */
        }
        return 0;
}

/**
 *      init_chipset_ali15x3    -       Initialise an ALi IDE controller
 *      @dev: PCI device
 *
 *      This function initializes the ALI IDE controller and where 
 *      appropriate also sets up the 1533 southbridge.
 */

static int init_chipset_ali15x3(struct pci_dev *dev)
{
        unsigned long flags;
        u8 tmpbyte;
        struct pci_dev *north = pci_get_slot(dev->bus, PCI_DEVFN(0,0));

        m5229_revision = dev->revision;

        isa_dev = pci_get_device(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M1533, NULL);

        local_irq_save(flags);

        if (m5229_revision < 0xC2) {
                /*
                 * revision 0x20 (1543-E, 1543-F)
                 * revision 0xC0, 0xC1 (1543C-C, 1543C-D, 1543C-E)
                 * clear CD-ROM DMA write bit, m5229, 0x4b, bit 7
                 */
                pci_read_config_byte(dev, 0x4b, &tmpbyte);
                /*
                 * clear bit 7
                 */
                pci_write_config_byte(dev, 0x4b, tmpbyte & 0x7F);
                /*
                 * check m1533, 0x5e, bit 1~4 == 1001 => & 00011110 = 00010010
                 */
                if (m5229_revision >= 0x20 && isa_dev) {
                        pci_read_config_byte(isa_dev, 0x5e, &tmpbyte);
                        chip_is_1543c_e = ((tmpbyte & 0x1e) == 0x12) ? 1: 0;
                }
                goto out;
        }

        /*
         * 1543C-B?, 1535, 1535D, 1553
         * Note 1: not all "motherboard" support this detection
         * Note 2: if no udma 66 device, the detection may "error".
         *         but in this case, we will not set the device to
         *         ultra 66, the detection result is not important
         */

        /*
         * enable "Cable Detection", m5229, 0x4b, bit3
         */
        pci_read_config_byte(dev, 0x4b, &tmpbyte);
        pci_write_config_byte(dev, 0x4b, tmpbyte | 0x08);

        /*
         * We should only tune the 1533 enable if we are using an ALi
         * North bridge. We might have no north found on some zany
         * box without a device at 0:0.0. The ALi bridge will be at
         * 0:0.0 so if we didn't find one we know what is cooking.
         */
        if (north && north->vendor != PCI_VENDOR_ID_AL)
                goto out;

        if (m5229_revision < 0xC5 && isa_dev)
        {       
                /*
                 * set south-bridge's enable bit, m1533, 0x79
                 */

                pci_read_config_byte(isa_dev, 0x79, &tmpbyte);
                if (m5229_revision == 0xC2) {
                        /*
                         * 1543C-B0 (m1533, 0x79, bit 2)
                         */
                        pci_write_config_byte(isa_dev, 0x79, tmpbyte | 0x04);
                } else if (m5229_revision >= 0xC3) {
                        /*
                         * 1553/1535 (m1533, 0x79, bit 1)
                         */
                        pci_write_config_byte(isa_dev, 0x79, tmpbyte | 0x02);
                }
        }

out:
        /*
         * CD_ROM DMA on (m5229, 0x53, bit0)
         *      Enable this bit even if we want to use PIO.
         * PIO FIFO off (m5229, 0x53, bit1)
         *      The hardware will use 0x54h and 0x55h to control PIO FIFO.
         *      (Not on later devices it seems)
         *
         *      0x53 changes meaning on later revs - we must no touch
         *      bit 1 on them.  Need to check if 0x20 is the right break.
         */
        if (m5229_revision >= 0x20) {
                pci_read_config_byte(dev, 0x53, &tmpbyte);

                if (m5229_revision <= 0x20)
                        tmpbyte = (tmpbyte & (~0x02)) | 0x01;
                else if (m5229_revision == 0xc7 || m5229_revision == 0xc8)
                        tmpbyte |= 0x03;
                else
                        tmpbyte |= 0x01;

                pci_write_config_byte(dev, 0x53, tmpbyte);
        }
        pci_dev_put(north);
        pci_dev_put(isa_dev);
        local_irq_restore(flags);
        return 0;
}

/*
 *      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_cable_detect        -       cable detection
 *      @hwif: IDE interface
 *
 *      This checks if the controller and the cable are capable
 *      of UDMA66 transfers. It doesn't check the drives.
 *      But see note 2 below!
 *
 *      FIXME: frobs bits that are not defined on newer ALi devicea
 */

static u8 ali_cable_detect(ide_hwif_t *hwif)
{
        struct pci_dev *dev = to_pci_dev(hwif->dev);
        unsigned long flags;
        u8 cbl = ATA_CBL_PATA40, tmpbyte;

        local_irq_save(flags);

        if (m5229_revision >= 0xC2) {
                /*
                 * m5229 80-pin cable detection (from Host View)
                 *
                 * 0x4a bit0 is 0 => primary channel has 80-pin
                 * 0x4a bit1 is 0 => secondary channel has 80-pin
                 *
                 * Certain laptops use short but suitable cables
                 * and don't implement the detect logic.
                 */
                if (ali_cable_override(dev))
                        cbl = ATA_CBL_PATA40_SHORT;
                else {
                        pci_read_config_byte(dev, 0x4a, &tmpbyte);
                        if ((tmpbyte & (1 << hwif->channel)) == 0)
                                cbl = ATA_CBL_PATA80;
                }
        }

        local_irq_restore(flags);

        return cbl;
}

#ifndef CONFIG_SPARC64
/**
 *      init_hwif_ali15x3       -       Initialize the ALI IDE x86 stuff
 *      @hwif: interface to configure
 *
 *      Obtain the IRQ tables for an ALi based IDE solution on the PC
 *      class platforms. This part of the code isn't applicable to the
 *      Sparc systems.
 */

static void __devinit init_hwif_ali15x3 (ide_hwif_t *hwif)
{
        u8 ideic, inmir;
        s8 irq_routing_table[] = { -1,  9, 3, 10, 4,  5, 7,  6,
                                      1, 11, 0, 12, 0, 14, 0, 15 };
        int irq = -1;

        if (isa_dev) {
                /*
                 * read IDE interface control
                 */
                pci_read_config_byte(isa_dev, 0x58, &ideic);

                /* bit0, bit1 */
                ideic = ideic & 0x03;

                /* get IRQ for IDE Controller */
                if ((hwif->channel && ideic == 0x03) ||
                    (!hwif->channel && !ideic)) {
                        /*
                         * get SIRQ1 routing table
                         */
                        pci_read_config_byte(isa_dev, 0x44, &inmir);
                        inmir = inmir & 0x0f;
                        irq = irq_routing_table[inmir];
                } else if (hwif->channel && !(ideic & 0x01)) {
                        /*
                         * get SIRQ2 routing table
                         */
                        pci_read_config_byte(isa_dev, 0x75, &inmir);
                        inmir = inmir & 0x0f;
                        irq = irq_routing_table[inmir];
                }
                if(irq >= 0)
                        hwif->irq = irq;
        }
}
#else
#define init_hwif_ali15x3 NULL
#endif /* CONFIG_SPARC64 */

/**
 *      init_dma_ali15x3        -       set up DMA on ALi15x3
 *      @hwif: IDE interface
 *      @d: IDE port info
 *
 *      Set up the DMA functionality on the ALi 15x3.
 */

static int __devinit init_dma_ali15x3(ide_hwif_t *hwif,
                                      const struct ide_port_info *d)
{
        struct pci_dev *dev = to_pci_dev(hwif->dev);
        unsigned long base = ide_pci_dma_base(hwif, d);

        if (base == 0)
                return -1;

        hwif->dma_base = base;

        if (ide_pci_check_simplex(hwif, d) < 0)
                return -1;

        if (ide_pci_set_master(dev, d->name) < 0)
                return -1;

        if (!hwif->channel)
                outb(inb(base + 2) & 0x60, base + 2);

        printk(KERN_INFO "    %s: BM-DMA at 0x%04lx-0x%04lx\n",
                         hwif->name, base, base + 7);

        if (ide_allocate_dma_engine(hwif))
                return -1;

        return 0;
}

static const struct ide_port_ops ali_port_ops = {
        .set_pio_mode           = ali_set_pio_mode,
        .set_dma_mode           = ali_set_dma_mode,
        .udma_filter            = ali_udma_filter,
        .cable_detect           = ali_cable_detect,
};

static const struct ide_dma_ops ali_dma_ops = {
        .dma_host_set           = ide_dma_host_set,
        .dma_setup              = ide_dma_setup,
        .dma_start              = ide_dma_start,
        .dma_end                = ide_dma_end,
        .dma_test_irq           = ide_dma_test_irq,
        .dma_lost_irq           = ide_dma_lost_irq,
        .dma_check              = ali_dma_check,
        .dma_timer_expiry       = ide_dma_sff_timer_expiry,
        .dma_sff_read_status    = ide_dma_sff_read_status,
};

static const struct ide_port_info ali15x3_chipset __devinitdata = {
        .name           = DRV_NAME,
        .init_chipset   = init_chipset_ali15x3,
        .init_hwif      = init_hwif_ali15x3,
        .init_dma       = init_dma_ali15x3,
        .port_ops       = &ali_port_ops,
        .dma_ops        = &sff_dma_ops,
        .pio_mask       = ATA_PIO5,
        .swdma_mask     = ATA_SWDMA2,
        .mwdma_mask     = ATA_MWDMA2,
};

/**
 *      alim15x3_init_one       -       set up an ALi15x3 IDE controller
 *      @dev: PCI device to set up
 *
 *      Perform the actual set up for an ALi15x3 that has been found by the
 *      hot plug layer.
 */
 
static int __devinit alim15x3_init_one(struct pci_dev *dev, const struct pci_device_id *id)
{
        struct ide_port_info d = ali15x3_chipset;
        u8 rev = dev->revision, idx = id->driver_data;

        /* don't use LBA48 DMA on ALi devices before rev 0xC5 */
        if (rev <= 0xC4)
                d.host_flags |= IDE_HFLAG_NO_LBA48_DMA;

        if (rev >= 0x20) {
                if (rev == 0x20)
                        d.host_flags |= IDE_HFLAG_NO_ATAPI_DMA;

                if (rev < 0xC2)
                        d.udma_mask = ATA_UDMA2;
                else if (rev == 0xC2 || rev == 0xC3)
                        d.udma_mask = ATA_UDMA4;
                else if (rev == 0xC4)
                        d.udma_mask = ATA_UDMA5;
                else
                        d.udma_mask = ATA_UDMA6;

                d.dma_ops = &ali_dma_ops;
        } else {
                d.host_flags |= IDE_HFLAG_NO_DMA;

                d.mwdma_mask = d.swdma_mask = 0;
        }

        if (idx == 0)
                d.host_flags |= IDE_HFLAG_CLEAR_SIMPLEX;

        return ide_pci_init_one(dev, &d, NULL);
}


static const struct pci_device_id alim15x3_pci_tbl[] = {
        { PCI_VDEVICE(AL, PCI_DEVICE_ID_AL_M5229), 0 },
        { PCI_VDEVICE(AL, PCI_DEVICE_ID_AL_M5228), 1 },
        { 0, },
};
MODULE_DEVICE_TABLE(pci, alim15x3_pci_tbl);

static struct pci_driver alim15x3_pci_driver = {
        .name           = "ALI15x3_IDE",
        .id_table       = alim15x3_pci_tbl,
        .probe          = alim15x3_init_one,
        .remove         = ide_pci_remove,
        .suspend        = ide_pci_suspend,
        .resume         = ide_pci_resume,
};

static int __init ali15x3_ide_init(void)
{
        return ide_pci_register_driver(&alim15x3_pci_driver);
}

static void __exit ali15x3_ide_exit(void)
{
        pci_unregister_driver(&alim15x3_pci_driver);
}

module_init(ali15x3_ide_init);
module_exit(ali15x3_ide_exit);

MODULE_AUTHOR("Michael Aubry, Andrzej Krzysztofowicz, CJ, Andre Hedrick, Alan Cox");
MODULE_DESCRIPTION("PCI driver module for ALi 15x3 IDE");
MODULE_LICENSE("GPL");