ide-lib.c

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#include <linux/module.h>
#include <linux/types.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/timer.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/major.h>
#include <linux/errno.h>
#include <linux/genhd.h>
#include <linux/blkpg.h>
#include <linux/slab.h>
#include <linux/pci.h>
#include <linux/delay.h>
#include <linux/hdreg.h>
#include <linux/ide.h>
#include <linux/bitops.h>

#include <asm/byteorder.h>
#include <asm/irq.h>
#include <asm/uaccess.h>
#include <asm/io.h>

/*
 *	IDE library routines. These are plug in code that most 
 *	drivers can use but occasionally may be weird enough
 *	to want to do their own thing with
 *
 *	Add common non I/O op stuff here. Make sure it has proper
 *	kernel-doc function headers or your patch will be rejected
 */

static const char *udma_str[] =
	 { "UDMA/16", "UDMA/25",  "UDMA/33",  "UDMA/44",
	   "UDMA/66", "UDMA/100", "UDMA/133", "UDMA7" };
static const char *mwdma_str[] =
	{ "MWDMA0", "MWDMA1", "MWDMA2" };
static const char *swdma_str[] =
	{ "SWDMA0", "SWDMA1", "SWDMA2" };
static const char *pio_str[] =
	{ "PIO0", "PIO1", "PIO2", "PIO3", "PIO4", "PIO5" };

/**
 *	ide_xfer_verbose	-	return IDE mode names
 *	@mode: transfer mode
 *
 *	Returns a constant string giving the name of the mode
 *	requested.
 */

const char *ide_xfer_verbose(u8 mode)
{
	const char *s;
	u8 i = mode & 0xf;

	if (mode >= XFER_UDMA_0 && mode <= XFER_UDMA_7)
		s = udma_str[i];
	else if (mode >= XFER_MW_DMA_0 && mode <= XFER_MW_DMA_2)
		s = mwdma_str[i];
	else if (mode >= XFER_SW_DMA_0 && mode <= XFER_SW_DMA_2)
		s = swdma_str[i];
	else if (mode >= XFER_PIO_0 && mode <= XFER_PIO_5)
		s = pio_str[i & 0x7];
	else if (mode == XFER_PIO_SLOW)
		s = "PIO SLOW";
	else
		s = "XFER ERROR";

	return s;
}

EXPORT_SYMBOL(ide_xfer_verbose);

/**
 *	ide_rate_filter		-	filter transfer mode
 *	@drive: IDE device
 *	@speed: desired speed
 *
 *	Given the available transfer modes this function returns
 *	the best available speed at or below the speed requested.
 *
 *	TODO: check device PIO capabilities
 */

static u8 ide_rate_filter(ide_drive_t *drive, u8 speed)
{
	ide_hwif_t *hwif = drive->hwif;
	u8 mode = ide_find_dma_mode(drive, speed);

	if (mode == 0) {
		if (hwif->pio_mask)
			mode = fls(hwif->pio_mask) - 1 + XFER_PIO_0;
		else
			mode = XFER_PIO_4;
	}

//	printk("%s: mode 0x%02x, speed 0x%02x\n", __FUNCTION__, mode, speed);

	return min(speed, mode);
}

/*
 * Standard (generic) timings for PIO modes, from ATA2 specification.
 * These timings are for access to the IDE data port register *only*.
 * Some drives may specify a mode, while also specifying a different
 * value for cycle_time (from drive identification data).
 */
const ide_pio_timings_t ide_pio_timings[6] = {
	{ 70,	165,	600 },	/* PIO Mode 0 */
	{ 50,	125,	383 },	/* PIO Mode 1 */
	{ 30,	100,	240 },	/* PIO Mode 2 */
	{ 30,	80,	180 },	/* PIO Mode 3 with IORDY */
	{ 25,	70,	120 },	/* PIO Mode 4 with IORDY */
	{ 20,	50,	100 }	/* PIO Mode 5 with IORDY (nonstandard) */
};

EXPORT_SYMBOL_GPL(ide_pio_timings);

/*
 * Shared data/functions for determining best PIO mode for an IDE drive.
 * Most of this stuff originally lived in cmd640.c, and changes to the
 * ide_pio_blacklist[] table should be made with EXTREME CAUTION to avoid
 * breaking the fragile cmd640.c support.
 */

/*
 * Black list. Some drives incorrectly report their maximal PIO mode,
 * at least in respect to CMD640. Here we keep info on some known drives.
 */
static struct ide_pio_info {
	const char	*name;
	int		pio;
} ide_pio_blacklist [] = {
/*	{ "Conner Peripherals 1275MB - CFS1275A", 4 }, */
	{ "Conner Peripherals 540MB - CFS540A", 3 },

	{ "WDC AC2700",  3 },
	{ "WDC AC2540",  3 },
	{ "WDC AC2420",  3 },
	{ "WDC AC2340",  3 },
	{ "WDC AC2250",  0 },
	{ "WDC AC2200",  0 },
	{ "WDC AC21200", 4 },
	{ "WDC AC2120",  0 },
	{ "WDC AC2850",  3 },
	{ "WDC AC1270",  3 },
	{ "WDC AC1170",  1 },
	{ "WDC AC1210",  1 },
	{ "WDC AC280",   0 },
/*	{ "WDC AC21000", 4 }, */
	{ "WDC AC31000", 3 },
	{ "WDC AC31200", 3 },
/*	{ "WDC AC31600", 4 }, */

	{ "Maxtor 7131 AT", 1 },
	{ "Maxtor 7171 AT", 1 },
	{ "Maxtor 7213 AT", 1 },
	{ "Maxtor 7245 AT", 1 },
	{ "Maxtor 7345 AT", 1 },
	{ "Maxtor 7546 AT", 3 },
	{ "Maxtor 7540 AV", 3 },

	{ "SAMSUNG SHD-3121A", 1 },
	{ "SAMSUNG SHD-3122A", 1 },
	{ "SAMSUNG SHD-3172A", 1 },

/*	{ "ST51080A", 4 },
 *	{ "ST51270A", 4 },
 *	{ "ST31220A", 4 },
 *	{ "ST31640A", 4 },
 *	{ "ST32140A", 4 },
 *	{ "ST3780A",  4 },
 */
	{ "ST5660A",  3 },
	{ "ST3660A",  3 },
	{ "ST3630A",  3 },
	{ "ST3655A",  3 },
	{ "ST3391A",  3 },
	{ "ST3390A",  1 },
	{ "ST3600A",  1 },
	{ "ST3290A",  0 },
	{ "ST3144A",  0 },
	{ "ST3491A",  1 },	/* reports 3, should be 1 or 2 (depending on */	
				/* drive) according to Seagates FIND-ATA program */

	{ "QUANTUM ELS127A", 0 },
	{ "QUANTUM ELS170A", 0 },
	{ "QUANTUM LPS240A", 0 },
	{ "QUANTUM LPS210A", 3 },
	{ "QUANTUM LPS270A", 3 },
	{ "QUANTUM LPS365A", 3 },
	{ "QUANTUM LPS540A", 3 },
	{ "QUANTUM LIGHTNING 540A", 3 },
	{ "QUANTUM LIGHTNING 730A", 3 },

        { "QUANTUM FIREBALL_540", 3 }, /* Older Quantum Fireballs don't work */
        { "QUANTUM FIREBALL_640", 3 }, 
        { "QUANTUM FIREBALL_1080", 3 },
        { "QUANTUM FIREBALL_1280", 3 },
	{ NULL,	0 }
};

/**
 *	ide_scan_pio_blacklist 	-	check for a blacklisted drive
 *	@model: Drive model string
 *
 *	This routine searches the ide_pio_blacklist for an entry
 *	matching the start/whole of the supplied model name.
 *
 *	Returns -1 if no match found.
 *	Otherwise returns the recommended PIO mode from ide_pio_blacklist[].
 */

static int ide_scan_pio_blacklist (char *model)
{
	struct ide_pio_info *p;

	for (p = ide_pio_blacklist; p->name != NULL; p++) {
		if (strncmp(p->name, model, strlen(p->name)) == 0)
			return p->pio;
	}
	return -1;
}

unsigned int ide_pio_cycle_time(ide_drive_t *drive, u8 pio)
{
	struct hd_driveid *id = drive->id;
	int cycle_time = 0;

	if (id->field_valid & 2) {
		if (id->capability & 8)
			cycle_time = id->eide_pio_iordy;
		else
			cycle_time = id->eide_pio;
	}

	/* conservative "downgrade" for all pre-ATA2 drives */
	if (pio < 3) {
		if (cycle_time && cycle_time < ide_pio_timings[pio].cycle_time)
			cycle_time = 0; /* use standard timing */
	}

	return cycle_time ? cycle_time : ide_pio_timings[pio].cycle_time;
}

EXPORT_SYMBOL_GPL(ide_pio_cycle_time);

/**
 *	ide_get_best_pio_mode	-	get PIO mode from drive
 *	@drive: drive to consider
 *	@mode_wanted: preferred mode
 *	@max_mode: highest allowed mode
 *
 *	This routine returns the recommended PIO settings for a given drive,
 *	based on the drive->id information and the ide_pio_blacklist[].
 *
 *	Drive PIO mode is auto-selected if 255 is passed as mode_wanted.
 *	This is used by most chipset support modules when "auto-tuning".
 */

u8 ide_get_best_pio_mode (ide_drive_t *drive, u8 mode_wanted, u8 max_mode)
{
	int pio_mode;
	struct hd_driveid* id = drive->id;
	int overridden  = 0;

	if (mode_wanted != 255)
		return min_t(u8, mode_wanted, max_mode);

	if ((drive->hwif->host_flags & IDE_HFLAG_PIO_NO_BLACKLIST) == 0 &&
	    (pio_mode = ide_scan_pio_blacklist(id->model)) != -1) {
		printk(KERN_INFO "%s: is on PIO blacklist\n", drive->name);
	} else {
		pio_mode = id->tPIO;
		if (pio_mode > 2) {	/* 2 is maximum allowed tPIO value */
			pio_mode = 2;
			overridden = 1;
		}
		if (id->field_valid & 2) {	  /* drive implements ATA2? */
			if (id->capability & 8) { /* IORDY supported? */
				if (id->eide_pio_modes & 7) {
					overridden = 0;
					if (id->eide_pio_modes & 4)
						pio_mode = 5;
					else if (id->eide_pio_modes & 2)
						pio_mode = 4;
					else
						pio_mode = 3;
				}
			}
		}

		if (overridden)
			printk(KERN_INFO "%s: tPIO > 2, assuming tPIO = 2\n",
					 drive->name);

		/*
		 * Conservative "downgrade" for all pre-ATA2 drives
		 */
		if ((drive->hwif->host_flags & IDE_HFLAG_PIO_NO_DOWNGRADE) == 0 &&
		    pio_mode && pio_mode < 4) {
			pio_mode--;
			printk(KERN_INFO "%s: applying conservative "
					 "PIO \"downgrade\"\n", drive->name);
		}
	}

	if (pio_mode > max_mode)
		pio_mode = max_mode;

	return pio_mode;