sched: clean up some control group code

[linux-2.6/openmoko-kernel/knife-kernel.git] / drivers / ide / pci / sl82c105.c

/*
 * linux/drivers/ide/pci/sl82c105.c
 *
 * SL82C105/Winbond 553 IDE driver
 *
 * Maintainer unknown.
 *
 * Drive tuning added from Rebel.com's kernel sources
 *  -- Russell King (15/11/98) linux@arm.linux.org.uk
 * 
 * Merge in Russell's HW workarounds, fix various problems
 * with the timing registers setup.
 *  -- Benjamin Herrenschmidt (01/11/03) benh@kernel.crashing.org
 *
 * Copyright (C) 2006-2007 MontaVista Software, Inc. <source@mvista.com>
 */

#include <linux/types.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/timer.h>
#include <linux/mm.h>
#include <linux/ioport.h>
#include <linux/interrupt.h>
#include <linux/blkdev.h>
#include <linux/hdreg.h>
#include <linux/pci.h>
#include <linux/ide.h>

#include <asm/io.h>
#include <asm/dma.h>

#undef DEBUG

#ifdef DEBUG
#define DBG(arg) printk arg
#else
#define DBG(fmt,...)
#endif
/*
 * SL82C105 PCI config register 0x40 bits.
 */
#define CTRL_IDE_IRQB   (1 << 30)
#define CTRL_IDE_IRQA   (1 << 28)
#define CTRL_LEGIRQ     (1 << 11)
#define CTRL_P1F16      (1 << 5)
#define CTRL_P1EN       (1 << 4)
#define CTRL_P0F16      (1 << 1)
#define CTRL_P0EN       (1 << 0)

/*
 * Convert a PIO mode and cycle time to the required on/off times
 * for the interface.  This has protection against runaway timings.
 */
static unsigned int get_pio_timings(ide_drive_t *drive, u8 pio)
{
        unsigned int cmd_on, cmd_off;
        u8 iordy = 0;

        cmd_on  = (ide_pio_timings[pio].active_time + 29) / 30;
        cmd_off = (ide_pio_cycle_time(drive, pio) - 30 * cmd_on + 29) / 30;

        if (cmd_on == 0)
                cmd_on = 1;

        if (cmd_off == 0)
                cmd_off = 1;

        if (pio > 2 || ide_dev_has_iordy(drive->id))
                iordy = 0x40;

        return (cmd_on - 1) << 8 | (cmd_off - 1) | iordy;
}

/*
 * Configure the chipset for PIO mode.
 */
static void sl82c105_set_pio_mode(ide_drive_t *drive, const u8 pio)
{
        struct pci_dev *dev     = HWIF(drive)->pci_dev;
        int reg                 = 0x44 + drive->dn * 4;
        u16 drv_ctrl;

        drv_ctrl = get_pio_timings(drive, pio);

        /*
         * Store the PIO timings so that we can restore them
         * in case DMA will be turned off...
         */
        drive->drive_data &= 0xffff0000;
        drive->drive_data |= drv_ctrl;

        if (!drive->using_dma) {
                /*
                 * If we are actually using MW DMA, then we can not
                 * reprogram the interface drive control register.
                 */
                pci_write_config_word(dev, reg,  drv_ctrl);
                pci_read_config_word (dev, reg, &drv_ctrl);
        }

        printk(KERN_DEBUG "%s: selected %s (%dns) (%04X)\n", drive->name,
                          ide_xfer_verbose(pio + XFER_PIO_0),
                          ide_pio_cycle_time(drive, pio), drv_ctrl);
}

/*
 * Configure the chipset for DMA mode.
 */
static void sl82c105_set_dma_mode(ide_drive_t *drive, const u8 speed)
{
        static u16 mwdma_timings[] = {0x0707, 0x0201, 0x0200};
        u16 drv_ctrl;

        DBG(("sl82c105_tune_chipset(drive:%s, speed:%s)\n",
             drive->name, ide_xfer_verbose(speed)));

        switch (speed) {
        case XFER_MW_DMA_2:
        case XFER_MW_DMA_1:
        case XFER_MW_DMA_0:
                drv_ctrl = mwdma_timings[speed - XFER_MW_DMA_0];

                /*
                 * Store the DMA timings so that we can actually program
                 * them when DMA will be turned on...
                 */
                drive->drive_data &= 0x0000ffff;
                drive->drive_data |= (unsigned long)drv_ctrl << 16;

                /*
                 * If we are already using DMA, we just reprogram
                 * the drive control register.
                 */
                if (drive->using_dma) {
                        struct pci_dev *dev     = HWIF(drive)->pci_dev;
                        int reg                 = 0x44 + drive->dn * 4;

                        pci_write_config_word(dev, reg, drv_ctrl);
                }
                break;
        default:
                return;
        }
}

/*
 * The SL82C105 holds off all IDE interrupts while in DMA mode until
 * all DMA activity is completed.  Sometimes this causes problems (eg,
 * when the drive wants to report an error condition).
 *
 * 0x7e is a "chip testing" register.  Bit 2 resets the DMA controller
 * state machine.  We need to kick this to work around various bugs.
 */
static inline void sl82c105_reset_host(struct pci_dev *dev)
{
        u16 val;

        pci_read_config_word(dev, 0x7e, &val);
        pci_write_config_word(dev, 0x7e, val | (1 << 2));
        pci_write_config_word(dev, 0x7e, val & ~(1 << 2));
}

/*
 * If we get an IRQ timeout, it might be that the DMA state machine
 * got confused.  Fix from Todd Inglett.  Details from Winbond.
 *
 * This function is called when the IDE timer expires, the drive
 * indicates that it is READY, and we were waiting for DMA to complete.
 */
static void sl82c105_dma_lost_irq(ide_drive_t *drive)
{
        ide_hwif_t *hwif        = HWIF(drive);
        struct pci_dev *dev     = hwif->pci_dev;
        u32 val, mask           = hwif->channel ? CTRL_IDE_IRQB : CTRL_IDE_IRQA;
        u8 dma_cmd;

        printk("sl82c105: lost IRQ, resetting host\n");

        /*
         * Check the raw interrupt from the drive.
         */
        pci_read_config_dword(dev, 0x40, &val);
        if (val & mask)
                printk("sl82c105: drive was requesting IRQ, but host lost it\n");

        /*
         * Was DMA enabled?  If so, disable it - we're resetting the
         * host.  The IDE layer will be handling the drive for us.
         */
        dma_cmd = inb(hwif->dma_command);
        if (dma_cmd & 1) {
                outb(dma_cmd & ~1, hwif->dma_command);
                printk("sl82c105: DMA was enabled\n");
        }

        sl82c105_reset_host(dev);
}

/*
 * ATAPI devices can cause the SL82C105 DMA state machine to go gaga.
 * Winbond recommend that the DMA state machine is reset prior to
 * setting the bus master DMA enable bit.
 *
 * The generic IDE core will have disabled the BMEN bit before this
 * function is called.
 */
static void sl82c105_dma_start(ide_drive_t *drive)
{
        ide_hwif_t *hwif        = HWIF(drive);
        struct pci_dev *dev     = hwif->pci_dev;

        sl82c105_reset_host(dev);
        ide_dma_start(drive);
}

static void sl82c105_dma_timeout(ide_drive_t *drive)
{
        DBG(("sl82c105_dma_timeout(drive:%s)\n", drive->name));

        sl82c105_reset_host(HWIF(drive)->pci_dev);
        ide_dma_timeout(drive);
}

static int sl82c105_ide_dma_on(ide_drive_t *drive)
{
        struct pci_dev *dev     = HWIF(drive)->pci_dev;
        int rc, reg             = 0x44 + drive->dn * 4;

        DBG(("sl82c105_ide_dma_on(drive:%s)\n", drive->name));

        rc = __ide_dma_on(drive);
        if (rc == 0) {
                pci_write_config_word(dev, reg, drive->drive_data >> 16);

                printk(KERN_INFO "%s: DMA enabled\n", drive->name);
        }
        return rc;
}

static void sl82c105_dma_off_quietly(ide_drive_t *drive)
{
        struct pci_dev *dev     = HWIF(drive)->pci_dev;
        int reg                 = 0x44 + drive->dn * 4;

        DBG(("sl82c105_dma_off_quietly(drive:%s)\n", drive->name));

        pci_write_config_word(dev, reg, drive->drive_data);

        ide_dma_off_quietly(drive);
}

/*
 * Ok, that is nasty, but we must make sure the DMA timings
 * won't be used for a PIO access. The solution here is
 * to make sure the 16 bits mode is diabled on the channel
 * when DMA is enabled, thus causing the chip to use PIO0
 * timings for those operations.
 */
static void sl82c105_selectproc(ide_drive_t *drive)
{
        ide_hwif_t *hwif        = HWIF(drive);
        struct pci_dev *dev     = hwif->pci_dev;
        u32 val, old, mask;

        //DBG(("sl82c105_selectproc(drive:%s)\n", drive->name));

        mask = hwif->channel ? CTRL_P1F16 : CTRL_P0F16;
        old = val = (u32)pci_get_drvdata(dev);
        if (drive->using_dma)
                val &= ~mask;
        else
                val |= mask;
        if (old != val) {
                pci_write_config_dword(dev, 0x40, val); 
                pci_set_drvdata(dev, (void *)val);
        }
}

/*
 * ATA reset will clear the 16 bits mode in the control
 * register, we need to update our cache
 */
static void sl82c105_resetproc(ide_drive_t *drive)
{
        struct pci_dev *dev = HWIF(drive)->pci_dev;
        u32 val;

        DBG(("sl82c105_resetproc(drive:%s)\n", drive->name));

        pci_read_config_dword(dev, 0x40, &val);
        pci_set_drvdata(dev, (void *)val);
}

/*
 * Return the revision of the Winbond bridge
 * which this function is part of.
 */
static unsigned int sl82c105_bridge_revision(struct pci_dev *dev)
{
        struct pci_dev *bridge;

        /*
         * The bridge should be part of the same device, but function 0.
         */
        bridge = pci_get_bus_and_slot(dev->bus->number,
                               PCI_DEVFN(PCI_SLOT(dev->devfn), 0));
        if (!bridge)
                return -1;

        /*
         * Make sure it is a Winbond 553 and is an ISA bridge.
         */
        if (bridge->vendor != PCI_VENDOR_ID_WINBOND ||
            bridge->device != PCI_DEVICE_ID_WINBOND_83C553 ||
            bridge->class >> 8 != PCI_CLASS_BRIDGE_ISA) {
                pci_dev_put(bridge);
                return -1;
        }
        /*
         * We need to find function 0's revision, not function 1
         */
        pci_dev_put(bridge);

        return bridge->revision;
}

/*
 * Enable the PCI device
 * 
 * --BenH: It's arch fixup code that should enable channels that
 * have not been enabled by firmware. I decided we can still enable
 * channel 0 here at least, but channel 1 has to be enabled by
 * firmware or arch code. We still set both to 16 bits mode.
 */
static unsigned int __devinit init_chipset_sl82c105(struct pci_dev *dev, const char *msg)
{
        u32 val;

        DBG(("init_chipset_sl82c105()\n"));

        pci_read_config_dword(dev, 0x40, &val);
        val |= CTRL_P0EN | CTRL_P0F16 | CTRL_P1F16;
        pci_write_config_dword(dev, 0x40, val);
        pci_set_drvdata(dev, (void *)val);

        return dev->irq;
}

/*
 * Initialise IDE channel
 */
static void __devinit init_hwif_sl82c105(ide_hwif_t *hwif)
{
        unsigned int rev;

        DBG(("init_hwif_sl82c105(hwif: ide%d)\n", hwif->index));

        hwif->set_pio_mode      = &sl82c105_set_pio_mode;
        hwif->set_dma_mode      = &sl82c105_set_dma_mode;
        hwif->selectproc        = &sl82c105_selectproc;
        hwif->resetproc         = &sl82c105_resetproc;

        if (!hwif->dma_base)
                return;

        rev = sl82c105_bridge_revision(hwif->pci_dev);
        if (rev <= 5) {
                /*
                 * Never ever EVER under any circumstances enable
                 * DMA when the bridge is this old.
                 */
                printk("    %s: Winbond W83C553 bridge revision %d, "
                       "BM-DMA disabled\n", hwif->name, rev);
                return;
        }

        hwif->mwdma_mask = ATA_MWDMA2;

        hwif->ide_dma_on                = &sl82c105_ide_dma_on;
        hwif->dma_off_quietly           = &sl82c105_dma_off_quietly;
        hwif->dma_lost_irq              = &sl82c105_dma_lost_irq;
        hwif->dma_start                 = &sl82c105_dma_start;
        hwif->dma_timeout               = &sl82c105_dma_timeout;

        if (hwif->mate)
                hwif->serialized = hwif->mate->serialized = 1;
}

static const struct ide_port_info sl82c105_chipset __devinitdata = {
        .name           = "W82C105",
        .init_chipset   = init_chipset_sl82c105,
        .init_hwif      = init_hwif_sl82c105,
        .enablebits     = {{0x40,0x01,0x01}, {0x40,0x10,0x10}},
        .host_flags     = IDE_HFLAG_IO_32BIT |
                          IDE_HFLAG_UNMASK_IRQS |
                          IDE_HFLAG_NO_AUTODMA |
                          IDE_HFLAG_BOOTABLE,
        .pio_mask       = ATA_PIO5,
};

static int __devinit sl82c105_init_one(struct pci_dev *dev, const struct pci_device_id *id)
{
        return ide_setup_pci_device(dev, &sl82c105_chipset);
}

static const struct pci_device_id sl82c105_pci_tbl[] = {
        { PCI_VDEVICE(WINBOND, PCI_DEVICE_ID_WINBOND_82C105), 0 },
        { 0, },
};
MODULE_DEVICE_TABLE(pci, sl82c105_pci_tbl);

static struct pci_driver driver = {
        .name           = "W82C105_IDE",
        .id_table       = sl82c105_pci_tbl,
        .probe          = sl82c105_init_one,
};

static int __init sl82c105_ide_init(void)
{
        return ide_pci_register_driver(&driver);
}

module_init(sl82c105_ide_init);

MODULE_DESCRIPTION("PCI driver module for W82C105 IDE");
MODULE_LICENSE("GPL");