linux/arch/ppc/platforms/prep_setup.c

/*
 *  Copyright (C) 1995  Linus Torvalds
 *  Adapted from 'alpha' version by Gary Thomas
 *  Modified by Cort Dougan (cort@cs.nmt.edu)
 *
 * Support for PReP (Motorola MTX/MVME)
 * by Troy Benjegerdes (hozer@drgw.net)
 */

/*
 * bootup setup stuff..
 */

#include <linux/delay.h>
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/ptrace.h>
#include <linux/slab.h>
#include <linux/user.h>
#include <linux/a.out.h>
#include <linux/screen_info.h>
#include <linux/major.h>
#include <linux/interrupt.h>
#include <linux/reboot.h>
#include <linux/init.h>
#include <linux/initrd.h>
#include <linux/ioport.h>
#include <linux/console.h>
#include <linux/timex.h>
#include <linux/pci.h>
#include <linux/seq_file.h>
#include <linux/root_dev.h>

#include <asm/sections.h>
#include <asm/mmu.h>
#include <asm/processor.h>
#include <asm/residual.h>
#include <asm/io.h>
#include <asm/pgtable.h>
#include <asm/cache.h>
#include <asm/dma.h>
#include <asm/machdep.h>
#include <asm/mc146818rtc.h>
#include <asm/mk48t59.h>
#include <asm/prep_nvram.h>
#include <asm/raven.h>
#include <asm/vga.h>
#include <asm/time.h>
#include <asm/mpc10x.h>
#include <asm/i8259.h>
#include <asm/open_pic.h>
#include <asm/pci-bridge.h>
#include <asm/todc.h>

/* prep registers for L2 */
#define CACHECRBA       0x80000823      /* Cache configuration register address */
#define L2CACHE_MASK	0x03	/* Mask for 2 L2 Cache bits */
#define L2CACHE_512KB	0x00	/* 512KB */
#define L2CACHE_256KB	0x01	/* 256KB */
#define L2CACHE_1MB	0x02	/* 1MB */
#define L2CACHE_NONE	0x03	/* NONE */
#define L2CACHE_PARITY  0x08    /* Mask for L2 Cache Parity Protected bit */

TODC_ALLOC();

extern unsigned char prep_nvram_read_val(int addr);
extern void prep_nvram_write_val(int addr,
				 unsigned char val);
extern unsigned char rs_nvram_read_val(int addr);
extern void rs_nvram_write_val(int addr,
				 unsigned char val);
extern void ibm_prep_init(void);

extern void prep_find_bridges(void);

int _prep_type;

extern void prep_residual_setup_pci(char *irq_edge_mask_lo, char *irq_edge_mask_hi);
extern void prep_sandalfoot_setup_pci(char *irq_edge_mask_lo, char *irq_edge_mask_hi);
extern void prep_thinkpad_setup_pci(char *irq_edge_mask_lo, char *irq_edge_mask_hi);
extern void prep_carolina_setup_pci(char *irq_edge_mask_lo, char *irq_edge_mask_hi);
extern void prep_tiger1_setup_pci(char *irq_edge_mask_lo, char *irq_edge_mask_hi);


#define cached_21	(((char *)(ppc_cached_irq_mask))[3])
#define cached_A1	(((char *)(ppc_cached_irq_mask))[2])

extern PTE *Hash, *Hash_end;
extern unsigned long Hash_size, Hash_mask;
extern int probingmem;
extern unsigned long loops_per_jiffy;

/* useful ISA ports */
#define PREP_SYSCTL	0x81c
/* present in the IBM reference design; possibly identical in Mot boxes: */
#define PREP_IBM_SIMM_ID	0x803	/* SIMM size: 32 or 8 MiB */
#define PREP_IBM_SIMM_PRESENCE	0x804
#define PREP_IBM_EQUIPMENT	0x80c
#define PREP_IBM_L2INFO	0x80d
#define PREP_IBM_PM1	0x82a	/* power management register 1 */
#define PREP_IBM_PLANAR	0x852	/* planar ID - identifies the motherboard */
#define PREP_IBM_DISP	0x8c0	/* 4-digit LED display */

/* Equipment Present Register masks: */
#define PREP_IBM_EQUIPMENT_RESERVED	0x80
#define PREP_IBM_EQUIPMENT_SCSIFUSE	0x40
#define PREP_IBM_EQUIPMENT_L2_COPYBACK	0x08
#define PREP_IBM_EQUIPMENT_L2_256	0x04
#define PREP_IBM_EQUIPMENT_CPU	0x02
#define PREP_IBM_EQUIPMENT_L2	0x01

/* planar ID values: */
/* Sandalfoot/Sandalbow (6015/7020) */
#define PREP_IBM_SANDALFOOT	0xfc
/* Woodfield, Thinkpad 850/860 (6042/7249) */
#define PREP_IBM_THINKPAD	0xff /* planar ID unimplemented */
/* PowerSeries 830/850 (6050/6070) */
#define PREP_IBM_CAROLINA_IDE_0	0xf0
#define PREP_IBM_CAROLINA_IDE_1	0xf1
#define PREP_IBM_CAROLINA_IDE_2	0xf2
#define PREP_IBM_CAROLINA_IDE_3	0xf3
/* 7248-43P */
#define PREP_IBM_CAROLINA_SCSI_0	0xf4
#define PREP_IBM_CAROLINA_SCSI_1	0xf5
#define PREP_IBM_CAROLINA_SCSI_2	0xf6
#define PREP_IBM_CAROLINA_SCSI_3	0xf7 /* missing from Carolina Tech Spec */
/* Tiger1 (7043-140) */
#define PREP_IBM_TIGER1_133		0xd1
#define PREP_IBM_TIGER1_166		0xd2
#define PREP_IBM_TIGER1_180		0xd3
#define PREP_IBM_TIGER1_xxx		0xd4 /* unknown, but probably exists */
#define PREP_IBM_TIGER1_333		0xd5 /* missing from Tiger Tech Spec */

/* setup_ibm_pci:
 * 	set Motherboard_map_name, Motherboard_map, Motherboard_routes.
 * 	return 8259 edge/level masks.
 */
void (*setup_ibm_pci)(char *irq_lo, char *irq_hi);

extern char *Motherboard_map_name; /* for use in *_cpuinfo */

/*
 * As found in the PReP reference implementation.
 * Used by Thinkpad, Sandalfoot (6015/7020), and all Motorola PReP.
 */
static void __init
prep_gen_enable_l2(void)
{
	outb(inb(PREP_SYSCTL) | 0x3, PREP_SYSCTL);
}

/* Used by Carolina and Tiger1 */
static void __init
prep_carolina_enable_l2(void)
{
	outb(inb(PREP_SYSCTL) | 0xc0, PREP_SYSCTL);
}

/* cpuinfo code common to all IBM PReP */
static void
prep_ibm_cpuinfo(struct seq_file *m)
{
	unsigned int equip_reg = inb(PREP_IBM_EQUIPMENT);

	seq_printf(m, "machine\t\t: PReP %s\n", Motherboard_map_name);

	seq_printf(m, "upgrade cpu\t: ");
	if (equip_reg & PREP_IBM_EQUIPMENT_CPU) {
		seq_printf(m, "not ");
	}
	seq_printf(m, "present\n");

	/* print info about the SCSI fuse */
	seq_printf(m, "scsi fuse\t: ");
	if (equip_reg & PREP_IBM_EQUIPMENT_SCSIFUSE)
		seq_printf(m, "ok");
	else
		seq_printf(m, "bad");
	seq_printf(m, "\n");

	/* print info about SIMMs */
	if (have_residual_data) {
		int i;
		seq_printf(m, "simms\t\t: ");
		for (i = 0; (res->ActualNumMemories) && (i < MAX_MEMS); i++) {
			if (res->Memories[i].SIMMSize != 0)
				seq_printf(m, "%d:%ldMiB ", i,
					(res->Memories[i].SIMMSize > 1024) ?
					res->Memories[i].SIMMSize>>20 :
					res->Memories[i].SIMMSize);
		}
		seq_printf(m, "\n");
	}
}

static int
prep_gen_cpuinfo(struct seq_file *m)
{
	prep_ibm_cpuinfo(m);
	return 0;
}

static int
prep_sandalfoot_cpuinfo(struct seq_file *m)
{
	unsigned int equip_reg = inb(PREP_IBM_EQUIPMENT);

	prep_ibm_cpuinfo(m);

	/* report amount and type of L2 cache present */
	seq_printf(m, "L2 cache\t: ");
	if (equip_reg & PREP_IBM_EQUIPMENT_L2) {
		seq_printf(m, "not present");
	} else {
		if (equip_reg & PREP_IBM_EQUIPMENT_L2_256)
			seq_printf(m, "256KiB");
		else
			seq_printf(m, "unknown size");

		if (equip_reg & PREP_IBM_EQUIPMENT_L2_COPYBACK)
			seq_printf(m, ", copy-back");
		else
			seq_printf(m, ", write-through");
	}
	seq_printf(m, "\n");

	return 0;
}

static int
prep_thinkpad_cpuinfo(struct seq_file *m)
{
	unsigned int equip_reg = inb(PREP_IBM_EQUIPMENT);
	char *cpubus_speed, *pci_speed;

	prep_ibm_cpuinfo(m);

	/* report amount and type of L2 cache present */
	seq_printf(m, "l2 cache\t: ");
	if ((equip_reg & 0x1) == 0) {
		switch ((equip_reg & 0xc) >> 2) {
			case 0x0:
				seq_printf(m, "128KiB look-aside 2-way write-through\n");
				break;
			case 0x1:
				seq_printf(m, "512KiB look-aside direct-mapped write-back\n");
				break;
			case 0x2:
				seq_printf(m, "256KiB look-aside 2-way write-through\n");
				break;
			case 0x3:
				seq_printf(m, "256KiB look-aside direct-mapped write-back\n");
				break;
		}
	} else {
		seq_printf(m, "not present\n");
	}

	/* report bus speeds because we can */
	if ((equip_reg & 0x80) == 0) {
		switch ((equip_reg & 0x30) >> 4) {
			case 0x1:
				cpubus_speed = "50";
				pci_speed = "25";
				break;
			case 0x3:
				cpubus_speed = "66";
				pci_speed = "33";
				break;
			default:
				cpubus_speed = "unknown";
				pci_speed = "unknown";
				break;
		}
	} else {
		switch ((equip_reg & 0x30) >> 4) {
			case 0x1:
				cpubus_speed = "25";
				pci_speed = "25";
				break;
			case 0x2:
				cpubus_speed = "60";
				pci_speed = "30";
				break;
			case 0x3:
				cpubus_speed = "33";
				pci_speed = "33";
				break;
			default:
				cpubus_speed = "unknown";
				pci_speed = "unknown";
				break;
		}
	}
	seq_printf(m, "60x bus\t\t: %sMHz\n", cpubus_speed);
	seq_printf(m, "pci bus\t\t: %sMHz\n", pci_speed);

	return 0;
}

static int
prep_carolina_cpuinfo(struct seq_file *m)
{
	unsigned int equip_reg = inb(PREP_IBM_EQUIPMENT);

	prep_ibm_cpuinfo(m);

	/* report amount and type of L2 cache present */
	seq_printf(m, "l2 cache\t: ");
	if ((equip_reg & 0x1) == 0) {
		unsigned int l2_reg = inb(PREP_IBM_L2INFO);

		/* L2 size */
		if ((l2_reg & 0x60) == 0)
			seq_printf(m, "256KiB");
		else if ((l2_reg & 0x60) == 0x20)
			seq_printf(m, "512KiB");
		else
			seq_printf(m, "unknown size");

		/* L2 type */
		if ((l2_reg & 0x3) == 0)
			seq_printf(m, ", async");
		else if ((l2_reg & 0x3) == 1)
			seq_printf(m, ", sync");
		else
			seq_printf(m, ", unknown type");

		seq_printf(m, "\n");
	} else {
		seq_printf(m, "not present\n");
	}

	return 0;
}

static int
prep_tiger1_cpuinfo(struct seq_file *m)
{
	unsigned int l2_reg = inb(PREP_IBM_L2INFO);

	prep_ibm_cpuinfo(m);

	/* report amount and type of L2 cache present */
	seq_printf(m, "l2 cache\t: ");
	if ((l2_reg & 0xf) == 0xf) {
		seq_printf(m, "not present\n");
	} else {
		if (l2_reg & 0x8)
			seq_printf(m, "async, ");
		else
			seq_printf(m, "sync burst, ");
	
		if (l2_reg & 0x4)
			seq_printf(m, "parity, ");
		else
			seq_printf(m, "no parity, ");
	
		switch (l2_reg & 0x3) {
			case 0x0:
				seq_printf(m, "256KiB\n");
				break;
			case 0x1:
				seq_printf(m, "512KiB\n");
				break;
			case 0x2:
				seq_printf(m, "1MiB\n");
				break;
			default:
				seq_printf(m, "unknown size\n");
				break;
		}
	}

	return 0;
}


/* Used by all Motorola PReP */
static int
prep_mot_cpuinfo(struct seq_file *m)
{
	unsigned int cachew = *((unsigned char *)CACHECRBA);

	seq_printf(m, "machine\t\t: PReP %s\n", Motherboard_map_name);

	/* report amount and type of L2 cache present */
	seq_printf(m, "l2 cache\t: ");
	switch (cachew & L2CACHE_MASK) {
		case L2CACHE_512KB:
			seq_printf(m, "512KiB");
			break;
		case L2CACHE_256KB:
			seq_printf(m, "256KiB");
			break;
		case L2CACHE_1MB:
			seq_printf(m, "1MiB");
			break;
		case L2CACHE_NONE:
			seq_printf(m, "none\n");
			goto no_l2;
			break;
		default:
			seq_printf(m, "%x\n", cachew);
	}

	seq_printf(m, ", parity %s",
			(cachew & L2CACHE_PARITY)? "enabled" : "disabled");

	seq_printf(m, " SRAM:");

	switch ( ((cachew & 0xf0) >> 4) & ~(0x3) ) {
		case 1: seq_printf(m, "synchronous, parity, flow-through\n");
				break;
		case 2: seq_printf(m, "asynchronous, no parity\n");
				break;
		case 3: seq_printf(m, "asynchronous, parity\n");
				break;
		default:seq_printf(m, "synchronous, pipelined, no parity\n");
				break;
	}

no_l2:
	/* print info about SIMMs */
	if (have_residual_data) {
		int i;
		seq_printf(m, "simms\t\t: ");
		for (i = 0; (res->ActualNumMemories) && (i < MAX_MEMS); i++) {
			if (res->Memories[i].SIMMSize != 0)
				seq_printf(m, "%d:%ldM ", i,
					(res->Memories[i].SIMMSize > 1024) ?
					res->Memories[i].SIMMSize>>20 :
					res->Memories[i].SIMMSize);
		}
		seq_printf(m, "\n");
	}

	return 0;
}

static void
prep_restart(char *cmd)
{
#define PREP_SP92	0x92	/* Special Port 92 */
	local_irq_disable(); /* no interrupts */

	/* set exception prefix high - to the prom */
	_nmask_and_or_msr(0, MSR_IP);

	/* make sure bit 0 (reset) is a 0 */
	outb( inb(PREP_SP92) & ~1L , PREP_SP92);
	/* signal a reset to system control port A - soft reset */
	outb( inb(PREP_SP92) | 1 , PREP_SP92);

	while ( 1 ) ;
	/* not reached */
#undef PREP_SP92
}

static void
prep_halt(void)
{
	local_irq_disable(); /* no interrupts */

	/* set exception prefix high - to the prom */
	_nmask_and_or_msr(0, MSR_IP);

	while ( 1 ) ;
	/* not reached */
}

/* Carrera is the power manager in the Thinkpads. Unfortunately not much is
 * known about it, so we can't power down.
 */
static void
prep_carrera_poweroff(void)
{
	prep_halt();
}

/*
 * On most IBM PReP's, power management is handled by a Signetics 87c750
 * behind the Utah component on the ISA bus. To access the 750 you must write
 * a series of nibbles to port 0x82a (decoded by the Utah). This is described
 * somewhat in the IBM Carolina Technical Specification.
 * -Hollis
 */
static void
utah_sig87c750_setbit(unsigned int bytenum, unsigned int bitnum, int value)
{
	/*
	 * byte1: 0 0 0 1 0  d  a5 a4
	 * byte2: 0 0 0 1 a3 a2 a1 a0
	 *
	 * d = the bit's value, enabled or disabled
	 * (a5 a4 a3) = the byte number, minus 20
	 * (a2 a1 a0) = the bit number
	 *
	 * example: set the 5th bit of byte 21 (21.5)
	 *     a5 a4 a3 = 001 (byte 1)
	 *     a2 a1 a0 = 101 (bit 5)
	 *
	 *     byte1 = 0001 0100 (0x14)
	 *     byte2 = 0001 1101 (0x1d)
	 */
	unsigned char byte1=0x10, byte2=0x10;

	/* the 750's '20.0' is accessed as '0.0' through Utah (which adds 20) */
	bytenum -= 20;

	byte1 |= (!!value) << 2;		/* set d */
	byte1 |= (bytenum >> 1) & 0x3;	/* set a5, a4 */

	byte2 |= (bytenum & 0x1) << 3;	/* set a3 */
	byte2 |= bitnum & 0x7;			/* set a2, a1, a0 */

	outb(byte1, PREP_IBM_PM1);	/* first nibble */
	mb();
	udelay(100);				/* important: let controller recover */

	outb(byte2, PREP_IBM_PM1);	/* second nibble */
	mb();
	udelay(100);				/* important: let controller recover */
}

static void
prep_sig750_poweroff(void)
{
	/* tweak the power manager found in most IBM PRePs (except Thinkpads) */

	local_irq_disable();
	/* set exception prefix high - to the prom */
	_nmask_and_or_msr(0, MSR_IP);

	utah_sig87c750_setbit(21, 5, 1); /* set bit 21.5, "PMEXEC_OFF" */

	while (1) ;
	/* not reached */
}

static int
prep_show_percpuinfo(struct seq_file *m, int i)
{
	/* PREP's without residual data will give incorrect values here */
	seq_printf(m, "clock\t\t: ");
	if (have_residual_data)
		seq_printf(m, "%ldMHz\n",
			   (res->VitalProductData.ProcessorHz > 1024) ?
			   res->VitalProductData.ProcessorHz / 1000000 :
			   res->VitalProductData.ProcessorHz);
	else
		seq_printf(m, "???\n");

	return 0;
}

/*
 * Fill out screen_info according to the residual data. This allows us to use
 * at least vesafb.
 */
static void __init
prep_init_vesa(void)
{
#if     (defined(CONFIG_FB_VGA16) || defined(CONFIG_FB_VGA16_MODULE) || \
	 defined(CONFIG_FB_VESA))
	PPC_DEVICE *vgadev = NULL;

	if (have_residual_data)
		vgadev = residual_find_device(~0, NULL, DisplayController,
							SVGAController, -1, 0);

	if (vgadev != NULL) {
		PnP_TAG_PACKET *pkt;

		pkt = PnP_find_large_vendor_packet(
				(unsigned char *)&res->DevicePnPHeap[vgadev->AllocatedOffset],
				0x04, 0); /* 0x04 = Display Tag */
		if (pkt != NULL) {
			unsigned char *ptr = (unsigned char *)pkt;

			if (ptr[4]) {
				/* graphics mode */
				screen_info.orig_video_isVGA = VIDEO_TYPE_VLFB;

				screen_info.lfb_depth = ptr[4] * 8;

				screen_info.lfb_width = swab16(*(short *)(ptr+6));
				screen_info.lfb_height = swab16(*(short *)(ptr+8));
				screen_info.lfb_linelength = swab16(*(short *)(ptr+10));

				screen_info.lfb_base = swab32(*(long *)(ptr+12));
				screen_info.lfb_size = swab32(*(long *)(ptr+20)) / 65536;
			}
		}
	}
#endif
}

/*
 * Set DBAT 2 to access 0x80000000 so early progress messages will work
 */
static __inline__ void
prep_set_bat(void)
{
	/* wait for all outstanding memory access to complete */
	mb();

	/* setup DBATs */
	mtspr(SPRN_DBAT2U, 0x80001ffe);
	mtspr(SPRN_DBAT2L, 0x8000002a);

	/* wait for updates */
	mb();
}

/*
 * IBM 3-digit status LED
 */
static unsigned int ibm_statusled_base;

static void
ibm_statusled_progress(char *s, unsigned short hex);

static int
ibm_statusled_panic(struct notifier_block *dummy1, unsigned long dummy2,
		    void * dummy3)
{
	ibm_statusled_progress(NULL, 0x505); /* SOS */
	return NOTIFY_DONE;
}

static struct notifier_block ibm_statusled_block = {
	ibm_statusled_panic,
	NULL,
	INT_MAX /* try to do it first */
};

static void
ibm_statusled_progress(char *s, unsigned short hex)
{
	static int notifier_installed;
	/*
	 * Progress uses 4 digits and we have only 3.  So, we map 0xffff to
	 * 0xfff for display switch off.  Out of range values are mapped to
	 * 0xeff, as I'm told 0xf00 and above are reserved for hardware codes.
	 * Install the panic notifier when the display is first switched off.
	 */
	if (hex == 0xffff) {
		hex = 0xfff;
		if (!notifier_installed) {
			++notifier_installed;
			atomic_notifier_chain_register(&panic_notifier_list,
						&ibm_statusled_block);
		}
	}
	else
		if (hex > 0xfff)
			hex = 0xeff;

	mb();
	outw(hex, ibm_statusled_base);
}

static void __init
ibm_statusled_init(void)
{
	/*
	 * The IBM 3-digit LED display is specified in the residual data
	 * as an operator panel device, type "System Status LED".  Find
	 * that device and determine its address.  We validate all the
	 * other parameters on the off-chance another, similar device
	 * exists.
	 */
	if (have_residual_data) {
		PPC_DEVICE *led;
		PnP_TAG_PACKET *pkt;

		led = residual_find_device(~0, NULL, SystemPeripheral,
					   OperatorPanel, SystemStatusLED, 0);
		if (!led)
			return;

		pkt = PnP_find_packet((unsigned char *)
		       &res->DevicePnPHeap[led->AllocatedOffset], S8_Packet, 0);
		if (!pkt)
			return;

		if (pkt->S8_Pack.IOInfo != ISAAddr16bit)
			return;
		if (*(unsigned short *)pkt->S8_Pack.RangeMin !=
		    *(unsigned short *)pkt->S8_Pack.RangeMax)
			return;
		if (pkt->S8_Pack.IOAlign != 2)
			return;
		if (pkt->S8_Pack.IONum != 2)
			return;

		ibm_statusled_base = ld_le16((unsigned short *)
					     (pkt->S8_Pack.RangeMin));
		ppc_md.progress = ibm_statusled_progress;
	}
}

static void __init
prep_setup_arch(void)
{
	unsigned char reg;
	int is_ide=0;

	/* init to some ~sane value until calibrate_delay() runs */
	loops_per_jiffy = 50000000;

	/* Lookup PCI host bridges */
	prep_find_bridges();

	/* Set up floppy in PS/2 mode */
	outb(0x09, SIO_CONFIG_RA);
	reg = inb(SIO_CONFIG_RD);
	reg = (reg & 0x3F) | 0x40;
	outb(reg, SIO_CONFIG_RD);
	outb(reg, SIO_CONFIG_RD);	/* Have to write twice to change! */

	switch ( _prep_type )
	{
	case _PREP_IBM:
		reg = inb(PREP_IBM_PLANAR);
		printk(KERN_INFO "IBM planar ID: %02x", reg);
		switch (reg) {
			case PREP_IBM_SANDALFOOT:
				prep_gen_enable_l2();
				setup_ibm_pci = prep_sandalfoot_setup_pci;
				ppc_md.power_off = prep_sig750_poweroff;
				ppc_md.show_cpuinfo = prep_sandalfoot_cpuinfo;
				break;
			case PREP_IBM_THINKPAD:
				prep_gen_enable_l2();
				setup_ibm_pci = prep_thinkpad_setup_pci;
				ppc_md.power_off = prep_carrera_poweroff;
				ppc_md.show_cpuinfo = prep_thinkpad_cpuinfo;
				break;
			default:
				if (have_residual_data) {
					prep_gen_enable_l2();
					setup_ibm_pci = prep_residual_setup_pci;
					ppc_md.power_off = prep_halt;
					ppc_md.show_cpuinfo = prep_gen_cpuinfo;
					break;
				}
				else
					printk(" - unknown! Assuming Carolina");
					/* fall through */
			case PREP_IBM_CAROLINA_IDE_0:
			case PREP_IBM_CAROLINA_IDE_1:
			case PREP_IBM_CAROLINA_IDE_2:
			case PREP_IBM_CAROLINA_IDE_3:
				is_ide = 1;
			case PREP_IBM_CAROLINA_SCSI_0:
			case PREP_IBM_CAROLINA_SCSI_1:
			case PREP_IBM_CAROLINA_SCSI_2:
			case PREP_IBM_CAROLINA_SCSI_3:
				prep_carolina_enable_l2();
				setup_ibm_pci = prep_carolina_setup_pci;
				ppc_md.power_off = prep_sig750_poweroff;
				ppc_md.show_cpuinfo = prep_carolina_cpuinfo;
				break;
			case PREP_IBM_TIGER1_133:
			case PREP_IBM_TIGER1_166:
			case PREP_IBM_TIGER1_180:
			case PREP_IBM_TIGER1_xxx:
			case PREP_IBM_TIGER1_333:
				prep_carolina_enable_l2();
				setup_ibm_pci = prep_tiger1_setup_pci;
				ppc_md.power_off = prep_sig750_poweroff;
				ppc_md.show_cpuinfo = prep_tiger1_cpuinfo;
				break;
		}
		printk("\n");

		/* default root device */
		if (is_ide)
			ROOT_DEV = MKDEV(IDE0_MAJOR, 3);
		else
			ROOT_DEV = MKDEV(SCSI_DISK0_MAJOR, 3);

		break;
	case _PREP_Motorola:
		prep_gen_enable_l2();
		ppc_md.power_off = prep_halt;
		ppc_md.show_cpuinfo = prep_mot_cpuinfo;

#ifdef CONFIG_BLK_DEV_INITRD
		if (initrd_start)
			ROOT_DEV = Root_RAM0;
		else
#endif
#ifdef CONFIG_ROOT_NFS
			ROOT_DEV = Root_NFS;
#else
			ROOT_DEV = Root_SDA2;
#endif
		break;
	}

	/* Read in NVRAM data */
	init_prep_nvram();

	/* if no bootargs, look in NVRAM */
	if ( cmd_line[0] == '\0' ) {
		char *bootargs;
		 bootargs = prep_nvram_get_var("bootargs");
		 if (bootargs != NULL) {
			 strcpy(cmd_line, bootargs);
			 /* again.. */
			 strcpy(boot_command_line, cmd_line);
		}
	}

	prep_init_vesa();

	switch (_prep_type) {
	case _PREP_Motorola:
		raven_init();
		break;
	case _PREP_IBM:
		ibm_prep_init();
		break;
	}

#ifdef CONFIG_VGA_CONSOLE
	/* vgacon.c needs to know where we mapped IO memory in io_block_mapping() */
	vgacon_remap_base = 0xf0000000;
	conswitchp = &vga_con;
#endif
}

/*
 * First, see if we can get this information from the residual data.
 * This is important on some IBM PReP systems.  If we cannot, we let the
 * TODC code handle doing this.
 */
static void __init
prep_calibrate_decr(void)
{
	if (have_residual_data) {
		unsigned long freq, divisor = 4;

		if ( res->VitalProductData.ProcessorBusHz ) {
			freq = res->VitalProductData.ProcessorBusHz;
			printk("time_init: decrementer frequency = %lu.%.6lu MHz\n",
					(freq/divisor)/1000000,
					(freq/divisor)%1000000);
			tb_to_us = mulhwu_scale_factor(freq/divisor, 1000000);
			tb_ticks_per_jiffy = freq / HZ / divisor;
		}
	}
	else
		todc_calibrate_decr();
}

static void __init
prep_init_IRQ(void)
{
	unsigned int pci_viddid, pci_did;

	if (OpenPIC_Addr != NULL) {
		openpic_init(NUM_8259_INTERRUPTS);
		/* We have a cascade on OpenPIC IRQ 0, Linux IRQ 16 */
		openpic_hookup_cascade(NUM_8259_INTERRUPTS, "82c59 cascade",
				       i8259_irq);
	}

	if (have_residual_data) {
		i8259_init(residual_isapic_addr(), 0);
		return;
	}

	/* If we have a Raven PCI bridge or a Hawk PCI bridge / Memory
	 * controller, we poll (as they have a different int-ack address). */
	early_read_config_dword(NULL, 0, 0, PCI_VENDOR_ID, &pci_viddid);
	pci_did = (pci_viddid & 0xffff0000) >> 16;
	if (((pci_viddid & 0xffff) == PCI_VENDOR_ID_MOTOROLA)
			&& ((pci_did == PCI_DEVICE_ID_MOTOROLA_RAVEN)
				|| (pci_did == PCI_DEVICE_ID_MOTOROLA_HAWK)))
		i8259_init(0, 0);
	else
		/* PCI interrupt ack address given in section 6.1.8 of the
		 * PReP specification. */
		i8259_init(MPC10X_MAPA_PCI_INTACK_ADDR, 0);
}

#ifdef CONFIG_SMP
/* PReP (MTX) support */
static int __init
smp_prep_probe(void)
{
	extern int mot_multi;

	if (mot_multi) {
		openpic_request_IPIs();
		smp_hw_index[1] = 1;
		return 2;
	}

	return 1;
}

static void __init
smp_prep_kick_cpu(int nr)
{
	*(unsigned long *)KERNELBASE = nr;
	asm volatile("dcbf 0,%0"::"r"(KERNELBASE):"memory");
	printk("CPU1 released, waiting\n");
}

static void __init
smp_prep_setup_cpu(int cpu_nr)
{
	if (OpenPIC_Addr)
		do_openpic_setup_cpu();
}

static struct smp_ops_t prep_smp_ops = {
	smp_openpic_message_pass,
	smp_prep_probe,
	smp_prep_kick_cpu,
	smp_prep_setup_cpu,
	.give_timebase = smp_generic_give_timebase,
	.take_timebase = smp_generic_take_timebase,
};
#endif /* CONFIG_SMP */

/*
 * Setup the bat mappings we're going to load that cover
 * the io areas.  RAM was mapped by mapin_ram().
 * -- Cort
 */
static void __init
prep_map_io(void)
{
	io_block_mapping(0x80000000, PREP_ISA_IO_BASE, 0x10000000, _PAGE_IO);
	io_block_mapping(0xf0000000, PREP_ISA_MEM_BASE, 0x08000000, _PAGE_IO);
}

static int __init
prep_request_io(void)
{
#ifdef CONFIG_NVRAM
	request_region(PREP_NVRAM_AS0, 0x8, "nvram");
#endif
	request_region(0x00,0x20,"dma1");
	request_region(0x40,0x20,"timer");
	request_region(0x80,0x10,"dma page reg");
	request_region(0xc0,0x20,"dma2");

	return 0;
}

device_initcall(prep_request_io);

void __init
prep_init(unsigned long r3, unsigned long r4, unsigned long r5,
		unsigned long r6, unsigned long r7)
{
#ifdef CONFIG_PREP_RESIDUAL
	/* make a copy of residual data */
	if ( r3 ) {
		memcpy((void *)res,(void *)(r3+KERNELBASE),
			 sizeof(RESIDUAL));
	}
#endif

	isa_io_base = PREP_ISA_IO_BASE;
	isa_mem_base = PREP_ISA_MEM_BASE;
	pci_dram_offset = PREP_PCI_DRAM_OFFSET;
	ISA_DMA_THRESHOLD = 0x00ffffff;
	DMA_MODE_READ = 0x44;
	DMA_MODE_WRITE = 0x48;
	ppc_do_canonicalize_irqs = 1;

	/* figure out what kind of prep workstation we are */
	if (have_residual_data) {
		if ( !strncmp(res->VitalProductData.PrintableModel,"IBM",3) )
			_prep_type = _PREP_IBM;
		else
			_prep_type = _PREP_Motorola;
	}
	else {
		/* assume motorola if no residual (netboot?) */
		_prep_type = _PREP_Motorola;
	}

#ifdef CONFIG_PREP_RESIDUAL
	/* Switch off all residual data processing if the user requests it */
	if (strstr(cmd_line, "noresidual") != NULL)
			res = NULL;
#endif

	/* Initialise progress early to get maximum benefit */
	prep_set_bat();
	ibm_statusled_init();

	ppc_md.setup_arch     = prep_setup_arch;
	ppc_md.show_percpuinfo = prep_show_percpuinfo;
	ppc_md.show_cpuinfo   = NULL; /* set in prep_setup_arch() */
	ppc_md.init_IRQ       = prep_init_IRQ;
	/* this gets changed later on if we have an OpenPIC -- Cort */
	ppc_md.get_irq        = i8259_irq;

	ppc_md.phys_mem_access_prot = pci_phys_mem_access_prot;

	ppc_md.restart        = prep_restart;
	ppc_md.power_off      = NULL; /* set in prep_setup_arch() */
	ppc_md.halt           = prep_halt;

	ppc_md.nvram_read_val = prep_nvram_read_val;
	ppc_md.nvram_write_val = prep_nvram_write_val;

	ppc_md.time_init      = todc_time_init;
	if (_prep_type == _PREP_IBM) {
		ppc_md.rtc_read_val = todc_mc146818_read_val;
		ppc_md.rtc_write_val = todc_mc146818_write_val;
		TODC_INIT(TODC_TYPE_MC146818, RTC_PORT(0), NULL, RTC_PORT(1),
				8);
	} else {
		TODC_INIT(TODC_TYPE_MK48T59, PREP_NVRAM_AS0, PREP_NVRAM_AS1,
				PREP_NVRAM_DATA, 8);
	}

	ppc_md.calibrate_decr = prep_calibrate_decr;
	ppc_md.set_rtc_time   = todc_set_rtc_time;
	ppc_md.get_rtc_time   = todc_get_rtc_time;

	ppc_md.setup_io_mappings = prep_map_io;

#ifdef CONFIG_SMP
	smp_ops			 = &prep_smp_ops;
#endif /* CONFIG_SMP */
}