Linux v2.6.13

[linux-2.6/next.git] / drivers / ide / legacy / ht6560b.c

/*
 *  linux/drivers/ide/legacy/ht6560b.c          Version 0.07    Feb  1, 2000
 *
 *  Copyright (C) 1995-2000  Linus Torvalds & author (see below)
 */

/*
 *
 *  Version 0.01        Initial version hacked out of ide.c
 *
 *  Version 0.02        Added support for PIO modes, auto-tune
 *
 *  Version 0.03        Some cleanups
 *
 *  Version 0.05        PIO mode cycle timings auto-tune using bus-speed
 *
 *  Version 0.06        Prefetch mode now defaults no OFF. To set
 *                      prefetch mode OFF/ON use "hdparm -p8/-p9".
 *                      Unmask irq is disabled when prefetch mode
 *                      is enabled.
 *
 *  Version 0.07        Trying to fix CD-ROM detection problem.
 *                      "Prefetch" mode bit OFF for ide disks and
 *                      ON for anything else.
 *
 *
 *  HT-6560B EIDE-controller support
 *  To activate controller support use kernel parameter "ide0=ht6560b".
 *  Use hdparm utility to enable PIO mode support.
 *
 *  Author:    Mikko Ala-Fossi            <maf@iki.fi>
 *             Jan Evert van Grootheest   <janevert@iae.nl>
 *
 *  Try:  http://www.maf.iki.fi/~maf/ht6560b/
 */

#define HT6560B_VERSION "v0.07"

#undef REALLY_SLOW_IO           /* most systems can safely undef this */

#include <linux/module.h>
#include <linux/config.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/timer.h>
#include <linux/mm.h>
#include <linux/ioport.h>
#include <linux/blkdev.h>
#include <linux/hdreg.h>
#include <linux/ide.h>
#include <linux/init.h>

#include <asm/io.h>

/* #define DEBUG */  /* remove comments for DEBUG messages */

/*
 * The special i/o-port that HT-6560B uses to configuration:
 *    bit0 (0x01): "1" selects secondary interface
 *    bit2 (0x04): "1" enables FIFO function
 *    bit5 (0x20): "1" enables prefetched data read function  (???)
 *
 * The special i/o-port that HT-6560A uses to configuration:
 *    bit0 (0x01): "1" selects secondary interface
 *    bit1 (0x02): "1" enables prefetched data read function
 *    bit2 (0x04): "0" enables multi-master system            (?)
 *    bit3 (0x08): "1" 3 cycle time, "0" 2 cycle time         (?)
 */
#define HT_CONFIG_PORT    0x3e6
#define HT_CONFIG(drivea) (u8)(((drivea)->drive_data & 0xff00) >> 8)
/*
 * FIFO + PREFETCH (both a/b-model)
 */
#define HT_CONFIG_DEFAULT 0x1c /* no prefetch */
/* #define HT_CONFIG_DEFAULT 0x3c */ /* with prefetch */
#define HT_SECONDARY_IF   0x01
#define HT_PREFETCH_MODE  0x20

/*
 * ht6560b Timing values:
 *
 * I reviewed some assembler source listings of htide drivers and found
 * out how they setup those cycle time interfacing values, as they at Holtek
 * call them. IDESETUP.COM that is supplied with the drivers figures out
 * optimal values and fetches those values to drivers. I found out that
 * they use IDE_SELECT_REG to fetch timings to the ide board right after
 * interface switching. After that it was quite easy to add code to
 * ht6560b.c.
 *
 * IDESETUP.COM gave me values 0x24, 0x45, 0xaa, 0xff that worked fine
 * for hda and hdc. But hdb needed higher values to work, so I guess
 * that sometimes it is necessary to give higher value than IDESETUP
 * gives.   [see cmd640.c for an extreme example of this. -ml]
 *
 * Perhaps I should explain something about these timing values:
 * The higher nibble of value is the Recovery Time  (rt) and the lower nibble
 * of the value is the Active Time  (at). Minimum value 2 is the fastest and
 * the maximum value 15 is the slowest. Default values should be 15 for both.
 * So 0x24 means 2 for rt and 4 for at. Each of the drives should have
 * both values, and IDESETUP gives automatically rt=15 st=15 for CDROMs or
 * similar. If value is too small there will be all sorts of failures.
 *
 * Timing byte consists of
 *      High nibble:  Recovery Cycle Time  (rt)
 *           The valid values range from 2 to 15. The default is 15.
 *
 *      Low nibble:   Active Cycle Time    (at)
 *           The valid values range from 2 to 15. The default is 15.
 *
 * You can obtain optimized timing values by running Holtek IDESETUP.COM
 * for DOS. DOS drivers get their timing values from command line, where
 * the first value is the Recovery Time and the second value is the
 * Active Time for each drive. Smaller value gives higher speed.
 * In case of failures you should probably fall back to a higher value.
 */
#define HT_TIMING(drivea) (u8)((drivea)->drive_data & 0x00ff)
#define HT_TIMING_DEFAULT 0xff

/*
 * This routine handles interface switching for the peculiar hardware design
 * on the F.G.I./Holtek HT-6560B VLB IDE interface.
 * The HT-6560B can only enable one IDE port at a time, and requires a
 * silly sequence (below) whenever we switch between primary and secondary.
 */

/*
 * This routine is invoked from ide.c to prepare for access to a given drive.
 */
static void ht6560b_selectproc (ide_drive_t *drive)
{
        unsigned long flags;
        static u8 current_select = 0;
        static u8 current_timing = 0;
        u8 select, timing;
        
        local_irq_save(flags);
        
        select = HT_CONFIG(drive);
        timing = HT_TIMING(drive);
        
        if (select != current_select || timing != current_timing) {
                current_select = select;
                current_timing = timing;
                if (drive->media != ide_disk || !drive->present)
                        select |= HT_PREFETCH_MODE;
                (void) HWIF(drive)->INB(HT_CONFIG_PORT);
                (void) HWIF(drive)->INB(HT_CONFIG_PORT);
                (void) HWIF(drive)->INB(HT_CONFIG_PORT);
                (void) HWIF(drive)->INB(HT_CONFIG_PORT);
                HWIF(drive)->OUTB(select, HT_CONFIG_PORT);
                /*
                 * Set timing for this drive:
                 */
                HWIF(drive)->OUTB(timing, IDE_SELECT_REG);
                (void) HWIF(drive)->INB(IDE_STATUS_REG);
#ifdef DEBUG
                printk("ht6560b: %s: select=%#x timing=%#x\n",
                        drive->name, select, timing);
#endif
        }
        local_irq_restore(flags);
}

/*
 * Autodetection and initialization of ht6560b
 */
static int __init try_to_init_ht6560b(void)
{
        u8 orig_value;
        int i;
        
        /* Autodetect ht6560b */
        if ((orig_value = inb(HT_CONFIG_PORT)) == 0xff)
                return 0;
        
        for (i=3;i>0;i--) {
                outb(0x00, HT_CONFIG_PORT);
                if (!( (~inb(HT_CONFIG_PORT)) & 0x3f )) {
                        outb(orig_value, HT_CONFIG_PORT);
                        return 0;
                }
        }
        outb(0x00, HT_CONFIG_PORT);
        if ((~inb(HT_CONFIG_PORT))& 0x3f) {
                outb(orig_value, HT_CONFIG_PORT);
                return 0;
        }
        /*
         * Ht6560b autodetected
         */
        outb(HT_CONFIG_DEFAULT, HT_CONFIG_PORT);
        outb(HT_TIMING_DEFAULT, 0x1f6);  /* IDE_SELECT_REG */
        (void) inb(0x1f7);               /* IDE_STATUS_REG */
        
        printk("\nht6560b " HT6560B_VERSION
               ": chipset detected and initialized"
#ifdef DEBUG
               " with debug enabled"
#endif
                );
        return 1;
}

static u8 ht_pio2timings(ide_drive_t *drive, u8 pio)
{
        int active_time, recovery_time;
        int active_cycles, recovery_cycles;
        ide_pio_data_t d;
        int bus_speed = system_bus_clock();
        
        if (pio) {
                pio = ide_get_best_pio_mode(drive, pio, 5, &d);
                
                /*
                 *  Just like opti621.c we try to calculate the
                 *  actual cycle time for recovery and activity
                 *  according system bus speed.
                 */
                active_time = ide_pio_timings[pio].active_time;
                recovery_time = d.cycle_time 
                        - active_time
                        - ide_pio_timings[pio].setup_time;
                /*
                 *  Cycle times should be Vesa bus cycles
                 */
                active_cycles   = (active_time   * bus_speed + 999) / 1000;
                recovery_cycles = (recovery_time * bus_speed + 999) / 1000;
                /*
                 *  Upper and lower limits
                 */
                if (active_cycles   < 2)  active_cycles   = 2;
                if (recovery_cycles < 2)  recovery_cycles = 2;
                if (active_cycles   > 15) active_cycles   = 15;
                if (recovery_cycles > 15) recovery_cycles = 0;  /* 0==16 */
                
#ifdef DEBUG
                printk("ht6560b: drive %s setting pio=%d recovery=%d (%dns) active=%d (%dns)\n", drive->name, pio, recovery_cycles, recovery_time, active_cycles, active_time);
#endif
                
                return (u8)((recovery_cycles << 4) | active_cycles);
        } else {
                
#ifdef DEBUG
                printk("ht6560b: drive %s setting pio=0\n", drive->name);
#endif
                
                return HT_TIMING_DEFAULT;    /* default setting */
        }
}

/*
 *  Enable/Disable so called prefetch mode
 */
static void ht_set_prefetch(ide_drive_t *drive, u8 state)
{
        unsigned long flags;
        int t = HT_PREFETCH_MODE << 8;
        
        spin_lock_irqsave(&ide_lock, flags);
        
        /*
         *  Prefetch mode and unmask irq seems to conflict
         */
        if (state) {
                drive->drive_data |= t;   /* enable prefetch mode */
                drive->no_unmask = 1;
                drive->unmask = 0;
        } else {
                drive->drive_data &= ~t;  /* disable prefetch mode */
                drive->no_unmask = 0;
        }
        
        spin_unlock_irqrestore(&ide_lock, flags);
        
#ifdef DEBUG
        printk("ht6560b: drive %s prefetch mode %sabled\n", drive->name, (state ? "en" : "dis"));
#endif
}

static void tune_ht6560b (ide_drive_t *drive, u8 pio)
{
        unsigned long flags;
        u8 timing;
        
        switch (pio) {
        case 8:         /* set prefetch off */
        case 9:         /* set prefetch on */
                ht_set_prefetch(drive, pio & 1);
                return;
        }
        
        timing = ht_pio2timings(drive, pio);
        
        spin_lock_irqsave(&ide_lock, flags);
        
        drive->drive_data &= 0xff00;
        drive->drive_data |= timing;
        
        spin_unlock_irqrestore(&ide_lock, flags);
        
#ifdef DEBUG
        printk("ht6560b: drive %s tuned to pio mode %#x timing=%#x\n", drive->name, pio, timing);
#endif
}

/* Can be called directly from ide.c. */
int __init ht6560b_init(void)
{
        ide_hwif_t *hwif, *mate;
        int t;

        hwif = &ide_hwifs[0];
        mate = &ide_hwifs[1];

        if (!request_region(HT_CONFIG_PORT, 1, hwif->name)) {
                printk(KERN_NOTICE "%s: HT_CONFIG_PORT not found\n",
                        __FUNCTION__);
                return -ENODEV;
        }

        if (!try_to_init_ht6560b()) {
                printk(KERN_NOTICE "%s: HBA not found\n", __FUNCTION__);
                goto release_region;
        }

        hwif->chipset = ide_ht6560b;
        hwif->selectproc = &ht6560b_selectproc;
        hwif->tuneproc = &tune_ht6560b;
        hwif->serialized = 1;   /* is this needed? */
        hwif->mate = mate;

        mate->chipset = ide_ht6560b;
        mate->selectproc = &ht6560b_selectproc;
        mate->tuneproc = &tune_ht6560b;
        mate->serialized = 1;   /* is this needed? */
        mate->mate = hwif;
        mate->channel = 1;

        /*
         * Setting default configurations for drives
         */
        t = (HT_CONFIG_DEFAULT << 8);
        t |= HT_TIMING_DEFAULT;
        hwif->drives[0].drive_data = t;
        hwif->drives[1].drive_data = t;

        t |= (HT_SECONDARY_IF << 8);
        mate->drives[0].drive_data = t;
        mate->drives[1].drive_data = t;

        probe_hwif_init(hwif);
        probe_hwif_init(mate);

        create_proc_ide_interfaces();

        return 0;

release_region:
        release_region(HT_CONFIG_PORT, 1);
        return -ENODEV;
}

#ifdef MODULE
module_init(ht6560b_init);
#endif

MODULE_AUTHOR("See Local File");
MODULE_DESCRIPTION("HT-6560B EIDE-controller support");
MODULE_LICENSE("GPL");