cmd640.c

ep9315平台下硬盘驱动的源码

 */
static void set_prefetch_mode (unsigned int index, int mode)
{
	ide_drive_t *drive = cmd_drives[index];
	int reg = prefetch_regs[index];
	u8 b;
	unsigned long flags;

	spin_lock_irqsave(&ide_lock, flags);
	b = __get_cmd640_reg(reg);
	if (mode) {	/* want prefetch on? */
#if CMD640_PREFETCH_MASKS
		drive->no_unmask = 1;
		drive->unmask = 0;
#endif
		drive->no_io_32bit = 0;
		b &= ~prefetch_masks[index];	/* enable prefetch */
	} else {
		drive->no_unmask = 0;
		drive->no_io_32bit = 1;
		drive->io_32bit = 0;
		b |= prefetch_masks[index];	/* disable prefetch */
	}
	__put_cmd640_reg(reg, b);
	spin_unlock_irqrestore(&ide_lock, flags);
}

/*
 * Dump out current drive clocks settings
 */
static void display_clocks (unsigned int index)
{
	u8 active_count, recovery_count;

	active_count = active_counts[index];
	if (active_count == 1)
		++active_count;
	recovery_count = recovery_counts[index];
	if (active_count > 3 && recovery_count == 1)
		++recovery_count;
	if (cmd640_chip_version > 1)
		recovery_count += 1;  /* cmd640b uses (count + 1)*/
	printk(", clocks=%d/%d/%d\n", setup_counts[index], active_count, recovery_count);
}

/*
 * Pack active and recovery counts into single byte representation
 * used by controller
 */
inline static u8 pack_nibbles (u8 upper, u8 lower)
{
	return ((upper & 0x0f) << 4) | (lower & 0x0f);
}

/*
 * This routine retrieves the initial drive timings from the chipset.
 */
static void __init retrieve_drive_counts (unsigned int index)
{
	u8 b;

	/*
	 * Get the internal setup timing, and convert to clock count
	 */
	b = get_cmd640_reg(arttim_regs[index]) & ~0x3f;
	switch (b) {
		case 0x00: b = 4; break;
		case 0x80: b = 3; break;
		case 0x40: b = 2; break;
		default:   b = 5; break;
	}
	setup_counts[index] = b;

	/*
	 * Get the active/recovery counts
	 */
	b = get_cmd640_reg(drwtim_regs[index]);
	active_counts[index]   = (b >> 4)   ? (b >> 4)   : 0x10;
	recovery_counts[index] = (b & 0x0f) ? (b & 0x0f) : 0x10;
}


/*
 * This routine writes the prepared setup/active/recovery counts
 * for a drive into the cmd640 chipset registers to active them.
 */
static void program_drive_counts (unsigned int index)
{
	unsigned long flags;
	u8 setup_count    = setup_counts[index];
	u8 active_count   = active_counts[index];
	u8 recovery_count = recovery_counts[index];

	/*
	 * Set up address setup count and drive read/write timing registers.
	 * Primary interface has individual count/timing registers for
	 * each drive.  Secondary interface has one common set of registers,
	 * so we merge the timings, using the slowest value for each timing.
	 */
	if (index > 1) {
		unsigned int mate;
		if (cmd_drives[mate = index ^ 1]->present) {
			if (setup_count < setup_counts[mate])
				setup_count = setup_counts[mate];
			if (active_count < active_counts[mate])
				active_count = active_counts[mate];
			if (recovery_count < recovery_counts[mate])
				recovery_count = recovery_counts[mate];
		}
	}

	/*
	 * Convert setup_count to internal chipset representation
	 */
	switch (setup_count) {
		case 4:	 setup_count = 0x00; break;
		case 3:	 setup_count = 0x80; break;
		case 1:
		case 2:	 setup_count = 0x40; break;
		default: setup_count = 0xc0; /* case 5 */
	}

	/*
	 * Now that everything is ready, program the new timings
	 */
	spin_lock_irqsave(&ide_lock, flags);
	/*
	 * Program the address_setup clocks into ARTTIM reg,
	 * and then the active/recovery counts into the DRWTIM reg
	 * (this converts counts of 16 into counts of zero -- okay).
	 */
	setup_count |= __get_cmd640_reg(arttim_regs[index]) & 0x3f;
	__put_cmd640_reg(arttim_regs[index], setup_count);
	__put_cmd640_reg(drwtim_regs[index], pack_nibbles(active_count, recovery_count));
	spin_unlock_irqrestore(&ide_lock, flags);
}

/*
 * Set a specific pio_mode for a drive
 */
static void cmd640_set_mode (unsigned int index, u8 pio_mode, unsigned int cycle_time)
{
	int setup_time, active_time, recovery_time, clock_time;
	u8 setup_count, active_count, recovery_count, recovery_count2, cycle_count;
	int bus_speed = system_bus_clock();

	if (pio_mode > 5)
		pio_mode = 5;
	setup_time  = ide_pio_timings[pio_mode].setup_time;
	active_time = ide_pio_timings[pio_mode].active_time;
	recovery_time = cycle_time - (setup_time + active_time);
	clock_time = 1000 / bus_speed;
	cycle_count = (cycle_time + clock_time - 1) / clock_time;

	setup_count = (setup_time + clock_time - 1) / clock_time;

	active_count = (active_time + clock_time - 1) / clock_time;
	if (active_count < 2)
		active_count = 2; /* minimum allowed by cmd640 */

	recovery_count = (recovery_time + clock_time - 1) / clock_time;
	recovery_count2 = cycle_count - (setup_count + active_count);
	if (recovery_count2 > recovery_count)
		recovery_count = recovery_count2;
	if (recovery_count < 2)
		recovery_count = 2; /* minimum allowed by cmd640 */
	if (recovery_count > 17) {
		active_count += recovery_count - 17;
		recovery_count = 17;
	}
	if (active_count > 16)
		active_count = 16; /* maximum allowed by cmd640 */
	if (cmd640_chip_version > 1)
		recovery_count -= 1;  /* cmd640b uses (count + 1)*/
	if (recovery_count > 16)
		recovery_count = 16; /* maximum allowed by cmd640 */

	setup_counts[index]    = setup_count;
	active_counts[index]   = active_count;
	recovery_counts[index] = recovery_count;

	/*
	 * In a perfect world, we might set the drive pio mode here
	 * (using WIN_SETFEATURE) before continuing.
	 *
	 * But we do not, because:
	 *	1) this is the wrong place to do it (proper is do_special() in ide.c)
	 * 	2) in practice this is rarely, if ever, necessary
	 */
	program_drive_counts (index);
}

/*
 * Drive PIO mode selection:
 */
static void cmd640_tune_drive (ide_drive_t *drive, u8 mode_wanted)
{
	u8 b;
	ide_pio_data_t  d;
	unsigned int index = 0;

	while (drive != cmd_drives[index]) {
		if (++index > 3) {
			printk("%s: bad news in cmd640_tune_drive\n", drive->name);
			return;
		}
	}
	switch (mode_wanted) {
		case 6: /* set fast-devsel off */
		case 7: /* set fast-devsel on */
			mode_wanted &= 1;
			b = get_cmd640_reg(CNTRL) & ~0x27;
			if (mode_wanted)
				b |= 0x27;
			put_cmd640_reg(CNTRL, b);
			printk("%s: %sabled cmd640 fast host timing (devsel)\n", drive->name, mode_wanted ? "en" : "dis");
			return;

		case 8: /* set prefetch off */
		case 9: /* set prefetch on */
			mode_wanted &= 1;
			set_prefetch_mode(index, mode_wanted);
			printk("%s: %sabled cmd640 prefetch\n", drive->name, mode_wanted ? "en" : "dis");
			return;
	}

	(void) ide_get_best_pio_mode (drive, mode_wanted, 5, &d);
	cmd640_set_mode (index, d.pio_mode, d.cycle_time);

	printk ("%s: selected cmd640 PIO mode%d (%dns)%s",
		drive->name,
		d.pio_mode,
		d.cycle_time,
		d.overridden ? " (overriding vendor mode)" : "");
	display_clocks(index);
	return;
}

#endif /* CONFIG_BLK_DEV_CMD640_ENHANCED */

static int pci_conf1(void)
{
	u32 tmp;
	unsigned long flags;

	spin_lock_irqsave(&ide_lock, flags);
	outb(0x01, 0xCFB);
	tmp = inl(0xCF8);
	outl(0x80000000, 0xCF8);
	if (inl(0xCF8) == 0x80000000) {
		outl(tmp, 0xCF8);
		spin_unlock_irqrestore(&ide_lock, flags);
		return 1;
	}
	outl(tmp, 0xCF8);
	spin_unlock_irqrestore(&ide_lock, flags);
	return 0;
}

static int pci_conf2(void)
{
	unsigned long flags;

	spin_lock_irqsave(&ide_lock, flags);
	outb(0x00, 0xCFB);
	outb(0x00, 0xCF8);
	outb(0x00, 0xCFA);
	if (inb(0xCF8) == 0x00 && inb(0xCF8) == 0x00) {
		spin_unlock_irqrestore(&ide_lock, flags);
		return 1;
	}
	spin_unlock_irqrestore(&ide_lock, flags);
	return 0;
}

/*
 * Probe for a cmd640 chipset, and initialize it if found.  Called from ide.c
 */
int __init ide_probe_for_cmd640x (void)
{
#ifdef CONFIG_BLK_DEV_CMD640_ENHANCED
	int second_port_toggled = 0;
#endif /* CONFIG_BLK_DEV_CMD640_ENHANCED */
	int second_port_cmd640 = 0;
	const char *bus_type, *port2;
	unsigned int index;
	u8 b, cfr;

	if (cmd640_vlb && probe_for_cmd640_vlb()) {
		bus_type = "VLB";
	} else {
		cmd640_vlb = 0;
		/* Find out what kind of PCI probing is supported otherwise
		   Justin Gibbs will sulk.. */
		if (pci_conf1() && probe_for_cmd640_pci1())
			bus_type = "PCI (type1)";
		else if (pci_conf2() && probe_for_cmd640_pci2())
			bus_type = "PCI (type2)";
		else
			return 0;
	}
	/*
	 * Undocumented magic (there is no 0x5b reg in specs)
	 */
	put_cmd640_reg(0x5b, 0xbd);
	if (get_cmd640_reg(0x5b) != 0xbd) {
		printk(KERN_ERR "ide: cmd640 init failed: wrong value in reg 0x5b\n");
		return 0;
	}
	put_cmd640_reg(0x5b, 0);

#ifdef CMD640_DUMP_REGS
	CMD640_DUMP_REGS;
#endif

	/*
	 * Documented magic begins here
	 */
	cfr = get_cmd640_reg(CFR);
	cmd640_chip_version = cfr & CFR_DEVREV;
	if (cmd640_chip_version == 0) {
		printk ("ide: bad cmd640 revision: %d\n", cmd640_chip_version);
		return 0;
	}

	/*
	 * Initialize data for primary port
	 */
	setup_device_ptrs ();
	printk("%s: buggy cmd640%c interface on %s, config=0x%02x\n",
	       cmd_hwif0->name, 'a' + cmd640_chip_version - 1, bus_type, cfr);
	cmd_hwif0->chipset = ide_cmd640;
#ifdef CONFIG_BLK_DEV_CMD640_ENHANCED
	cmd_hwif0->tuneproc = &cmd640_tune_drive;
#endif /* CONFIG_BLK_DEV_CMD640_ENHANCED */

	/*
	 * Ensure compatibility by always using the slowest timings
	 * for access to the drive's command register block,
	 * and reset the prefetch burstsize to default (512 bytes).
	 *
	 * Maybe we need a way to NOT do these on *some* systems?
	 */
	put_cmd640_reg(CMDTIM, 0);
	put_cmd640_reg(BRST, 0x40);

	/*
	 * Try to enable the secondary interface, if not already enabled
	 */
	if (cmd_hwif1->noprobe) {
		port2 = "not probed";
	} else {
		b = get_cmd640_reg(CNTRL);
		if (secondary_port_responding()) {
			if ((b & CNTRL_ENA_2ND)) {
				second_port_cmd640 = 1;
				port2 = "okay";
			} else if (cmd640_vlb) {
				second_port_cmd640 = 1;
				port2 = "alive";
			} else
				port2 = "not cmd640";
		} else {
			put_cmd640_reg(CNTRL, b ^ CNTRL_ENA_2ND); /* toggle the bit */
			if (secondary_port_responding()) {
				second_port_cmd640 = 1;
#ifdef CONFIG_BLK_DEV_CMD640_ENHANCED
				second_port_toggled = 1;
#endif /* CONFIG_BLK_DEV_CMD640_ENHANCED */
				port2 = "enabled";
			} else {
				put_cmd640_reg(CNTRL, b); /* restore original setting */
				port2 = "not responding";
			}
		}
	}

	/*
	 * Initialize data for secondary cmd640 port, if enabled
	 */
	if (second_port_cmd640) {
		cmd_hwif0->serialized = 1;
		cmd_hwif1->serialized = 1;
		cmd_hwif1->chipset = ide_cmd640;
		cmd_hwif0->mate = cmd_hwif1;
		cmd_hwif1->mate = cmd_hwif0;
		cmd_hwif1->channel = 1;
#ifdef CONFIG_BLK_DEV_CMD640_ENHANCED
		cmd_hwif1->tuneproc = &cmd640_tune_drive;
#endif /* CONFIG_BLK_DEV_CMD640_ENHANCED */
	}
	printk(KERN_INFO "%s: %sserialized, secondary interface %s\n", cmd_hwif1->name,
		cmd_hwif0->serialized ? "" : "not ", port2);

	/*
	 * Establish initial timings/prefetch for all drives.
	 * Do not unnecessarily disturb any prior BIOS setup of these.
	 */
	for (index = 0; index < (2 + (second_port_cmd640 << 1)); index++) {
		ide_drive_t *drive = cmd_drives[index];
#ifdef CONFIG_BLK_DEV_CMD640_ENHANCED
		if (drive->autotune || ((index > 1) && second_port_toggled)) {
	 		/*
	 		 * Reset timing to the slowest speed and turn off prefetch.
			 * This way, the drive identify code has a better chance.
			 */
			setup_counts    [index] = 4;	/* max possible */
			active_counts   [index] = 16;	/* max possible */
			recovery_counts [index] = 16;	/* max possible */
			program_drive_counts (index);
			set_prefetch_mode (index, 0);
			printk("cmd640: drive%d timings/prefetch cleared\n", index);
		} else {
			/*
			 * Record timings/prefetch without changing them.
			 * This preserves any prior BIOS setup.
			 */
			retrieve_drive_counts (index);
			check_prefetch (index);
			printk("cmd640: drive%d timings/prefetch(%s) preserved",
				index, drive->no_io_32bit ? "off" : "on");
			display_clocks(index);
		}
#else
		/*
		 * Set the drive unmask flags to match the prefetch setting
		 */
		check_prefetch (index);
		printk("cmd640: drive%d timings/prefetch(%s) preserved\n",
			index, drive->no_io_32bit ? "off" : "on");
#endif /* CONFIG_BLK_DEV_CMD640_ENHANCED */
	}

#ifdef CMD640_DUMP_REGS
	CMD640_DUMP_REGS;
#endif
	return 1;
}