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path: root/arch/sparc64/kernel/sbus.c
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/* $Id: sbus.c,v 1.6 1999/12/20 14:08:17 jj Exp $
 * sbus.c: UltraSparc SBUS controller support.
 *
 * Copyright (C) 1999 David S. Miller (davem@redhat.com)
 */

#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/mm.h>
#include <linux/spinlock.h>
#include <linux/malloc.h>
#include <linux/init.h>

#include <asm/page.h>
#include <asm/sbus.h>
#include <asm/io.h>
#include <asm/upa.h>
#include <asm/cache.h>
#include <asm/dma.h>
#include <asm/irq.h>

#include "iommu_common.h"

/* These should be allocated on an SMP_CACHE_BYTES
 * aligned boundry for optimal performance.
 *
 * On SYSIO, using an 8K page size we have 1GB of SBUS
 * DMA space mapped.  We divide this space into equally
 * sized clusters.  Currently we allow clusters up to a
 * size of 1MB.  If anything begins to generate DMA
 * mapping requests larger than this we will need to
 * increase things a bit.
 */

#define NCLUSTERS	8UL
#define ONE_GIG		(1UL * 1024UL * 1024UL * 1024UL)
#define CLUSTER_SIZE	(ONE_GIG / NCLUSTERS)
#define CLUSTER_MASK	(CLUSTER_SIZE - 1)
#define CLUSTER_NPAGES	(CLUSTER_SIZE >> PAGE_SHIFT)
#define MAP_BASE	((u32)0xc0000000)

struct sbus_iommu {
/*0x00*/spinlock_t		lock;

/*0x08*/iopte_t			*page_table;
/*0x10*/unsigned long		strbuf_regs;
/*0x18*/unsigned long		iommu_regs;
/*0x20*/unsigned long		sbus_control_reg;

/*0x28*/volatile unsigned long	strbuf_flushflag;

	/* If NCLUSTERS is ever decresed to 4 or lower,
	 * you must increase the size of the type of
	 * these counters.  You have been duly warned. -DaveM
	 */
/*0x30*/u16			lowest_free[NCLUSTERS];
};

/* Flushing heuristics */
#define IOMMU_DIAG_LIM	16
#define STRBUF_DIAG_LIM	32

/* Offsets from iommu_regs */
#define SYSIO_IOMMUREG_BASE	0x2400UL
#define IOMMU_CONTROL	(0x2400UL - 0x2400UL)	/* IOMMU control register */
#define IOMMU_TSBBASE	(0x2408UL - 0x2400UL)	/* TSB base address register */
#define IOMMU_FLUSH	(0x2410UL - 0x2400UL)	/* IOMMU flush register */
#define IOMMU_VADIAG	(0x4400UL - 0x2400UL)	/* SBUS virtual address diagnostic */
#define IOMMU_TAGCMP	(0x4408UL - 0x2400UL)	/* TLB tag compare diagnostics */
#define IOMMU_LRUDIAG	(0x4500UL - 0x2400UL)	/* IOMMU LRU queue diagnostics */
#define IOMMU_TAGDIAG	(0x4580UL - 0x2400UL)	/* TLB tag diagnostics */
#define IOMMU_DRAMDIAG	(0x4600UL - 0x2400UL)	/* TLB data RAM diagnostics */

#define IOMMU_DRAM_VALID	(1UL << 30UL)

static void __iommu_flush(struct sbus_iommu *iommu, u32 base, unsigned long npages)
{
	int hit = 0;

	if (npages <= IOMMU_DIAG_LIM) {
		while (npages--)
			upa_writeq(base + (npages << PAGE_SHIFT),
				   iommu->iommu_regs + IOMMU_FLUSH);
		hit = 1;
	} else {
		u32 limit = base + ((npages << PAGE_SHIFT) - 1UL);
		unsigned long dram = iommu->iommu_regs + IOMMU_DRAMDIAG;
		unsigned long tag = iommu->iommu_regs + IOMMU_TAGDIAG;
		int entry;

		for (entry = 0; entry < 16; entry++, dram += 8, tag += 8) {
			u32 addr = ((u32)upa_readq(tag) << PAGE_SHIFT);
			if (addr >= base && addr <= limit) {
				u64 val = upa_readq(dram);

				if (val & IOMMU_DRAM_VALID) {
					upa_writeq(addr,
						   iommu->iommu_regs + IOMMU_FLUSH);
					hit = 1;
				}
			}
		}
	}
	if (hit != 0)
		upa_readq(iommu->sbus_control_reg);
}

/* In an effort to keep latency under control, we special
 * case single page IOMMU flushes.
 */
static __inline__ void iommu_flush(struct sbus_iommu *iommu,
				   u32 base, unsigned long npages)
{
	if (npages == 1) {
		upa_writeq(base, iommu->iommu_regs + IOMMU_FLUSH);
		upa_readq(iommu->sbus_control_reg);
	} else
		__iommu_flush(iommu, base, npages);
}

/* Offsets from strbuf_regs */
#define SYSIO_STRBUFREG_BASE	0x2800UL
#define STRBUF_CONTROL	(0x2800UL - 0x2800UL)	/* Control */
#define STRBUF_PFLUSH	(0x2808UL - 0x2800UL)	/* Page flush/invalidate */
#define STRBUF_FSYNC	(0x2810UL - 0x2800UL)	/* Flush synchronization */
#define STRBUF_DRAMDIAG	(0x5000UL - 0x2800UL)	/* data RAM diagnostic */
#define STRBUF_ERRDIAG	(0x5400UL - 0x2800UL)	/* error status diagnostics */
#define STRBUF_PTAGDIAG	(0x5800UL - 0x2800UL)	/* Page tag diagnostics */
#define STRBUF_LTAGDIAG	(0x5900UL - 0x2800UL)	/* Line tag diagnostics */

#define STRBUF_TAG_VALID	0x02UL

static void strbuf_flush(struct sbus_iommu *iommu, u32 base, unsigned long npages)
{
	int hit = 0;

	iommu->strbuf_flushflag = 0UL;
	if (npages <= STRBUF_DIAG_LIM) {
		while (npages--)
			upa_writeq(base + (npages << PAGE_SHIFT),
				   iommu->strbuf_regs + STRBUF_PFLUSH);
		hit = 1;
	} else {
		u32 limit = base + ((npages << PAGE_SHIFT) - 1UL);
		unsigned long tag = iommu->strbuf_regs + STRBUF_PTAGDIAG;
		int entry;

		for (entry = 0; entry < 16; entry++, tag += 8) {
			u64 val = upa_readq(tag);

			if (val & STRBUF_TAG_VALID) {
				u32 addr = ((u32)(val & ~3UL)) << (PAGE_SHIFT - 2UL);
				if (addr >= base && addr <= limit) {
					upa_writeq(addr,
						   iommu->strbuf_regs + STRBUF_PFLUSH);
					hit = 1;
				}
			}
		}
	}
	if (hit != 0) {
		/* Whoopee cushion! */
		upa_writeq(__pa(&iommu->strbuf_flushflag),
			   iommu->strbuf_regs + STRBUF_FSYNC);
		upa_readq(iommu->sbus_control_reg);
		while (iommu->strbuf_flushflag == 0UL)
			membar("#LoadLoad");
	}
}

static iopte_t *alloc_streaming_cluster(struct sbus_iommu *iommu, unsigned long npages)
{
	iopte_t *iopte;
	unsigned long cnum, ent;

	cnum = 0;
	while ((1UL << cnum) < npages)
		cnum++;
	iopte  = iommu->page_table + (cnum * CLUSTER_NPAGES);
	iopte += ((ent = iommu->lowest_free[cnum]) << cnum);

	if (iopte_val(iopte[(1UL << cnum)]) == 0UL) {
		/* Fast path. */
		iommu->lowest_free[cnum] = ent + 1;
	} else {
		unsigned long pte_off = 1;

		ent += 1;
		do {
			pte_off++;
			ent++;
		} while (iopte_val(iopte[(pte_off << cnum)]) != 0UL);
		iommu->lowest_free[cnum] = ent;
	}

	/* I've got your streaming cluster right here buddy boy... */
	return iopte;
}

static void free_streaming_cluster(struct sbus_iommu *iommu, u32 base, unsigned long npages)
{
	unsigned long cnum, ent;
	iopte_t *iopte;

	cnum = 0;
	while ((1UL << cnum) < npages)
		cnum++;
	ent = (base & CLUSTER_MASK) >> (PAGE_SHIFT + cnum);
	iopte = iommu->page_table + ((base - MAP_BASE) >> PAGE_SHIFT);
	iopte_val(*iopte) = 0UL;
	if (ent < iommu->lowest_free[cnum])
		iommu->lowest_free[cnum] = ent;
}

/* We allocate consistant mappings from the end of cluster zero. */
static iopte_t *alloc_consistant_cluster(struct sbus_iommu *iommu, unsigned long npages)
{
	iopte_t *iopte;

	iopte = iommu->page_table + (1 * CLUSTER_NPAGES);
	while (iopte > iommu->page_table) {
		iopte--;
		if (!(iopte_val(*iopte) & IOPTE_VALID)) {
			unsigned long tmp = npages;

			while (--tmp) {
				iopte--;
				if (iopte_val(*iopte) & IOPTE_VALID)
					break;
			}
			if (tmp == 0)
				return iopte;
		}
	}
	return NULL;
}

static void free_consistant_cluster(struct sbus_iommu *iommu, u32 base, unsigned long npages)
{
	iopte_t *iopte = iommu->page_table + ((base - MAP_BASE) >> PAGE_SHIFT);

	while (npages--)
		*iopte++ = __iopte(0UL);
}

void *sbus_alloc_consistant(struct sbus_dev *sdev, long size, u32 *dvma_addr)
{
	unsigned long order, first_page, flags;
	struct sbus_iommu *iommu;
	iopte_t *iopte;
	void *ret;
	int npages;

	if (size <= 0 || sdev == NULL || dvma_addr == NULL)
		return NULL;

	size = PAGE_ALIGN(size);
	for (order = 0; order < 10; order++) {
		if ((PAGE_SIZE << order) >= size)
			break;
	}
	if (order == 10)
		return NULL;
	first_page = __get_free_pages(GFP_KERNEL, order);
	if (first_page == 0UL)
		return NULL;
	memset((char *)first_page, 0, PAGE_SIZE << order);

	iommu = sdev->bus->iommu;

	spin_lock_irqsave(&iommu->lock, flags);
	iopte = alloc_consistant_cluster(iommu, size >> PAGE_SHIFT);
	if (iopte == NULL) {
		spin_unlock_irqrestore(&iommu->lock, flags);
		free_pages(first_page, order);
		return NULL;
	}

	/* Ok, we're committed at this point. */
	*dvma_addr = MAP_BASE +	((iopte - iommu->page_table) << PAGE_SHIFT);
	ret = (void *) first_page;
	npages = size >> PAGE_SHIFT;
	while (npages--) {
		*iopte++ = __iopte(IOPTE_VALID | IOPTE_CACHE | IOPTE_WRITE |
				   (__pa(first_page) & IOPTE_PAGE));
		first_page += PAGE_SIZE;
	}
	iommu_flush(iommu, *dvma_addr, size >> PAGE_SHIFT);
	spin_unlock_irqrestore(&iommu->lock, flags);

	return ret;
}

void sbus_free_consistant(struct sbus_dev *sdev, long size, void *cpu, u32 dvma)
{
	unsigned long order, npages;
	struct sbus_iommu *iommu;

	if (size <= 0 || sdev == NULL || cpu == NULL)
		return;

	npages = PAGE_ALIGN(size) >> PAGE_SHIFT;
	iommu = sdev->bus->iommu;

	spin_lock_irq(&iommu->lock);
	free_consistant_cluster(iommu, dvma, npages);
	spin_unlock_irq(&iommu->lock);

	for (order = 0; order < 10; order++) {
		if ((PAGE_SIZE << order) >= size)
			break;
	}
	if (order < 10)
		free_pages((unsigned long)cpu, order);
}

u32 sbus_map_single(struct sbus_dev *sdev, void *ptr, long size)
{
	struct sbus_iommu *iommu = sdev->bus->iommu;
	unsigned long npages, phys_base, flags;
	iopte_t *iopte;
	u32 dma_base, offset;

	phys_base = (unsigned long) ptr;
	offset = (u32) (phys_base & ~PAGE_MASK);
	size = (PAGE_ALIGN(phys_base + size) - (phys_base & PAGE_MASK));
	phys_base = (unsigned long) __pa(phys_base & PAGE_MASK);

	spin_lock_irqsave(&iommu->lock, flags);
	npages = size >> PAGE_SHIFT;
	iopte = alloc_streaming_cluster(iommu, npages);
	dma_base = MAP_BASE + ((iopte - iommu->page_table) << PAGE_SHIFT);
	npages = size >> PAGE_SHIFT;
	while (npages--) {
		*iopte++ = __iopte(IOPTE_VALID | IOPTE_STBUF |
				   IOPTE_CACHE | IOPTE_WRITE |
				   (phys_base & IOPTE_PAGE));
		phys_base += PAGE_SIZE;
	}
	npages = size >> PAGE_SHIFT;
	iommu_flush(iommu, dma_base, npages);
	spin_unlock_irqrestore(&iommu->lock, flags);

	return (dma_base | offset);
}

void sbus_unmap_single(struct sbus_dev *sdev, u32 dma_addr, long size)
{
	struct sbus_iommu *iommu = sdev->bus->iommu;
	u32 dma_base = dma_addr & PAGE_MASK;
	unsigned long flags;

	size = (PAGE_ALIGN(dma_addr + size) - dma_base);

	spin_lock_irqsave(&iommu->lock, flags);
	free_streaming_cluster(iommu, dma_base, size >> PAGE_SHIFT);
	strbuf_flush(iommu, dma_base, size >> PAGE_SHIFT);
	spin_unlock_irqrestore(&iommu->lock, flags);
}

static inline void fill_sg(iopte_t *iopte, struct scatterlist *sg, int nents)
{
	struct scatterlist *dma_sg = sg;

	do {
		unsigned long pteval = ~0UL;
		u32 dma_npages;

		dma_npages = ((dma_sg->dvma_address & (PAGE_SIZE - 1UL)) +
			      dma_sg->dvma_length +
			      ((u32)(PAGE_SIZE - 1UL))) >> PAGE_SHIFT;
		do {
			unsigned long offset;
			signed int len;

			/* If we are here, we know we have at least one
			 * more page to map.  So walk forward until we
			 * hit a page crossing, and begin creating new
			 * mappings from that spot.
			 */
			for (;;) {
				unsigned long tmp;

				tmp = (unsigned long) __pa(sg->address);
				len = sg->length;
				if (((tmp ^ pteval) >> PAGE_SHIFT) != 0UL) {
					pteval = tmp & PAGE_MASK;
					offset = tmp & (PAGE_SIZE - 1UL);
					break;
				}
				if (((tmp ^ (tmp + len - 1UL)) >> PAGE_SHIFT) != 0UL) {
					pteval = (tmp + PAGE_SIZE) & PAGE_MASK;
					offset = 0UL;
					len -= (PAGE_SIZE - (tmp & (PAGE_SIZE - 1UL)));
					break;
				}
				sg++;
			}

			pteval = ((pteval & IOPTE_PAGE) |
				  IOPTE_VALID | IOPTE_STBUF |
				  IOPTE_CACHE | IOPTE_WRITE);
			while (len > 0) {
				*iopte++ = __iopte(pteval);
				pteval += PAGE_SIZE;
				len -= (PAGE_SIZE - offset);
				offset = 0;
				dma_npages--;
			}

			pteval = (pteval & IOPTE_PAGE) + len;
			sg++;

			/* Skip over any tail mappings we've fully mapped,
			 * adjusting pteval along the way.  Stop when we
			 * detect a page crossing event.
			 */
			while ((pteval << (64 - PAGE_SHIFT)) != 0UL &&
			       pteval == __pa(sg->address) &&
			       ((pteval ^
				 (__pa(sg->address) + sg->length - 1UL)) >> PAGE_SHIFT) == 0UL) {
				pteval += sg->length;
				sg++;
			}
			if ((pteval << (64 - PAGE_SHIFT)) == 0UL)
				pteval = ~0UL;
		} while (dma_npages != 0);
		dma_sg++;
	} while (dma_sg->dvma_length != 0);
}

int sbus_map_sg(struct sbus_dev *sdev, struct scatterlist *sg, int nents)
{
	struct sbus_iommu *iommu = sdev->bus->iommu;
	unsigned long flags, npages;
	iopte_t *iopte;
	u32 dma_base;
	struct scatterlist *sgtmp;
	int unused;

	/* Fast path single entry scatterlists. */
	if (nents == 1) {
		sg->dvma_address = sbus_map_single(sdev, sg->address, sg->length);
		sg->dvma_length = sg->length;
		return 1;
	}

	npages = prepare_sg(sg, nents);

	spin_lock_irqsave(&iommu->lock, flags);
	iopte = alloc_streaming_cluster(iommu, npages);
	dma_base = MAP_BASE + ((iopte - iommu->page_table) << PAGE_SHIFT);

	/* Normalize DVMA addresses. */
	sgtmp = sg;
	unused = nents;

	while (unused && sgtmp->dvma_length) {
		sgtmp->dvma_address += dma_base;
		sgtmp++;
		unused--;
	}

	fill_sg(iopte, sg, nents);
#ifdef VERIFY_SG
	verify_sglist(sg, nents, iopte, npages);
#endif
	iommu_flush(iommu, dma_base, npages);
	spin_unlock_irqrestore(&iommu->lock, flags);

	return nents - unused;
}

void sbus_unmap_sg(struct sbus_dev *sdev, struct scatterlist *sg, int nents)
{
	unsigned long size, flags;
	struct sbus_iommu *iommu;
	u32 dvma_base;
	int i;

	/* Fast path single entry scatterlists. */
	if (nents == 1) {
		sbus_unmap_single(sdev, sg->dvma_address, sg->dvma_length);
		return;
	}

	dvma_base = sg[0].dvma_address & PAGE_MASK;
	for (i = 0; i < nents; i++) {
		if (sg[i].dvma_length == 0)
			break;
	}
	i--;
	size = PAGE_ALIGN(sg[i].dvma_address + sg[i].dvma_length) - dvma_base;

	iommu = sdev->bus->iommu;
	spin_lock_irqsave(&iommu->lock, flags);
	free_streaming_cluster(iommu, dvma_base, size >> PAGE_SHIFT);
	strbuf_flush(iommu, dvma_base, size >> PAGE_SHIFT);
	spin_unlock_irqrestore(&iommu->lock, flags);
}

void sbus_dma_sync_single(struct sbus_dev *sdev, u32 base, long size)
{
	struct sbus_iommu *iommu = sdev->bus->iommu;
	unsigned long flags;

	size = (PAGE_ALIGN(base + size) - (base & PAGE_MASK));

	spin_lock_irqsave(&iommu->lock, flags);
	strbuf_flush(iommu, base & PAGE_MASK, size >> PAGE_SHIFT);
	spin_unlock_irqrestore(&iommu->lock, flags);
}

void sbus_dma_sync_sg(struct sbus_dev *sdev, struct scatterlist *sg, int nents)
{
	struct sbus_iommu *iommu = sdev->bus->iommu;
	unsigned long flags, size;
	u32 base;
	int i;

	base = sg[0].dvma_address & PAGE_MASK;
	for (i = 0; i < nents; i++) {
		if (sg[i].dvma_length == 0)
			break;
	}
	i--;
	size = PAGE_ALIGN(sg[i].dvma_address + sg[i].dvma_length) - base;

	spin_lock_irqsave(&iommu->lock, flags);
	strbuf_flush(iommu, base, size >> PAGE_SHIFT);
	spin_unlock_irqrestore(&iommu->lock, flags);
}

/* Enable 64-bit DVMA mode for the given device. */
void sbus_set_sbus64(struct sbus_dev *sdev, int bursts)
{
	struct sbus_iommu *iommu = sdev->bus->iommu;
	int slot = sdev->slot;
	unsigned long cfg_reg;
	u64 val;

	cfg_reg = iommu->sbus_control_reg;
	switch (slot) {
	case 0:
		cfg_reg += 0x20UL;
		break;
	case 1:
		cfg_reg += 0x28UL;
		break;
	case 2:
		cfg_reg += 0x30UL;
		break;
	case 3:
		cfg_reg += 0x38UL;
		break;
	case 13:
		cfg_reg += 0x40UL;
		break;
	case 14:
		cfg_reg += 0x48UL;
		break;
	case 15:
		cfg_reg += 0x50UL;
		break;

	default:
		return;
	};

	val = upa_readq(cfg_reg);
	if (val & (1UL << 14UL)) {
		/* Extended transfer mode already enabled. */
		return;
	}

	val |= (1UL << 14UL);

	if (bursts & DMA_BURST8)
		val |= (1UL << 1UL);
	if (bursts & DMA_BURST16)
		val |= (1UL << 2UL);
	if (bursts & DMA_BURST32)
		val |= (1UL << 3UL);
	if (bursts & DMA_BURST64)
		val |= (1UL << 4UL);
	upa_writeq(val, cfg_reg);
}

/* SBUS SYSIO INO number to Sparc PIL level. */
static unsigned char sysio_ino_to_pil[] = {
	0, 1, 2, 7, 5, 7, 8, 9,		/* SBUS slot 0 */
	0, 1, 2, 7, 5, 7, 8, 9,		/* SBUS slot 1 */
	0, 1, 2, 7, 5, 7, 8, 9,		/* SBUS slot 2 */
	0, 1, 2, 7, 5, 7, 8, 9,		/* SBUS slot 3 */
	3, /* Onboard SCSI */
	5, /* Onboard Ethernet */
/*XXX*/	8, /* Onboard BPP */
	0, /* Bogon */
       13, /* Audio */
/*XXX*/15, /* PowerFail */
	0, /* Bogon */
	0, /* Bogon */
       12, /* Zilog Serial Channels (incl. Keyboard/Mouse lines) */
       11, /* Floppy */
	0, /* Spare Hardware (bogon for now) */
	0, /* Keyboard (bogon for now) */
	0, /* Mouse (bogon for now) */
	0, /* Serial (bogon for now) */
     0, 0, /* Bogon, Bogon */
       10, /* Timer 0 */
       11, /* Timer 1 */
     0, 0, /* Bogon, Bogon */
       15, /* Uncorrectable SBUS Error */
       15, /* Correctable SBUS Error */
       15, /* SBUS Error */
/*XXX*/ 0, /* Power Management (bogon for now) */
};

/* INO number to IMAP register offset for SYSIO external IRQ's.
 * This should conform to both Sunfire/Wildfire server and Fusion
 * desktop designs.
 */
#define SYSIO_IMAP_SLOT0	0x2c04UL
#define SYSIO_IMAP_SLOT1	0x2c0cUL
#define SYSIO_IMAP_SLOT2	0x2c14UL
#define SYSIO_IMAP_SLOT3	0x2c1cUL
#define SYSIO_IMAP_SCSI		0x3004UL
#define SYSIO_IMAP_ETH		0x300cUL
#define SYSIO_IMAP_BPP		0x3014UL
#define SYSIO_IMAP_AUDIO	0x301cUL
#define SYSIO_IMAP_PFAIL	0x3024UL
#define SYSIO_IMAP_KMS		0x302cUL
#define SYSIO_IMAP_FLPY		0x3034UL
#define SYSIO_IMAP_SHW		0x303cUL
#define SYSIO_IMAP_KBD		0x3044UL
#define SYSIO_IMAP_MS		0x304cUL
#define SYSIO_IMAP_SER		0x3054UL
#define SYSIO_IMAP_TIM0		0x3064UL
#define SYSIO_IMAP_TIM1		0x306cUL
#define SYSIO_IMAP_UE		0x3074UL
#define SYSIO_IMAP_CE		0x307cUL
#define SYSIO_IMAP_SBERR	0x3084UL
#define SYSIO_IMAP_PMGMT	0x308cUL
#define SYSIO_IMAP_GFX		0x3094UL
#define SYSIO_IMAP_EUPA		0x309cUL

#define bogon     ((unsigned long) -1)
static unsigned long sysio_irq_offsets[] = {
	/* SBUS Slot 0 --> 3, level 1 --> 7 */
	SYSIO_IMAP_SLOT0, SYSIO_IMAP_SLOT0, SYSIO_IMAP_SLOT0, SYSIO_IMAP_SLOT0,
	SYSIO_IMAP_SLOT0, SYSIO_IMAP_SLOT0, SYSIO_IMAP_SLOT0, SYSIO_IMAP_SLOT0,
	SYSIO_IMAP_SLOT1, SYSIO_IMAP_SLOT1, SYSIO_IMAP_SLOT1, SYSIO_IMAP_SLOT1,
	SYSIO_IMAP_SLOT1, SYSIO_IMAP_SLOT1, SYSIO_IMAP_SLOT1, SYSIO_IMAP_SLOT1,
	SYSIO_IMAP_SLOT2, SYSIO_IMAP_SLOT2, SYSIO_IMAP_SLOT2, SYSIO_IMAP_SLOT2,
	SYSIO_IMAP_SLOT2, SYSIO_IMAP_SLOT2, SYSIO_IMAP_SLOT2, SYSIO_IMAP_SLOT2,
	SYSIO_IMAP_SLOT3, SYSIO_IMAP_SLOT3, SYSIO_IMAP_SLOT3, SYSIO_IMAP_SLOT3,
	SYSIO_IMAP_SLOT3, SYSIO_IMAP_SLOT3, SYSIO_IMAP_SLOT3, SYSIO_IMAP_SLOT3,

	/* Onboard devices (not relevant/used on SunFire). */
	SYSIO_IMAP_SCSI,
	SYSIO_IMAP_ETH,
	SYSIO_IMAP_BPP,
	bogon,
	SYSIO_IMAP_AUDIO,
	SYSIO_IMAP_PFAIL,
	bogon,
	bogon,
	SYSIO_IMAP_KMS,
	SYSIO_IMAP_FLPY,
	SYSIO_IMAP_SHW,
	SYSIO_IMAP_KBD,
	SYSIO_IMAP_MS,
	SYSIO_IMAP_SER,
	bogon,
	bogon,
	SYSIO_IMAP_TIM0,
	SYSIO_IMAP_TIM1,
	bogon,
	bogon,
	SYSIO_IMAP_UE,
	SYSIO_IMAP_CE,
	SYSIO_IMAP_SBERR,
	SYSIO_IMAP_PMGMT,
};

#undef bogon

#define NUM_SYSIO_OFFSETS (sizeof(sysio_irq_offsets) / sizeof(sysio_irq_offsets[0]))

/* Convert Interrupt Mapping register pointer to assosciated
 * Interrupt Clear register pointer, SYSIO specific version.
 */
#define SYSIO_ICLR_UNUSED0	0x3400UL
#define SYSIO_ICLR_SLOT0	0x340cUL
#define SYSIO_ICLR_SLOT1	0x344cUL
#define SYSIO_ICLR_SLOT2	0x348cUL
#define SYSIO_ICLR_SLOT3	0x34ccUL
static unsigned long sysio_imap_to_iclr(unsigned long imap)
{
	unsigned long diff = SYSIO_ICLR_UNUSED0 - SYSIO_IMAP_SLOT0;
	return imap + diff;
}

unsigned int sbus_build_irq(void *buscookie, unsigned int ino)
{
	struct sbus_bus *sbus = (struct sbus_bus *)buscookie;
	struct sbus_iommu *iommu = sbus->iommu;
	unsigned long reg_base = iommu->sbus_control_reg - 0x2000UL;
	unsigned long imap, iclr;
	int pil, sbus_level = 0;

	pil = sysio_ino_to_pil[ino];
	if (!pil) {
		printk("sbus_irq_build: Bad SYSIO INO[%x]\n", ino);
		panic("Bad SYSIO IRQ translations...");
	}
	imap = sysio_irq_offsets[ino];
	if (imap == ((unsigned long)-1)) {
		prom_printf("get_irq_translations: Bad SYSIO INO[%x] cpu[%d]\n",
			    ino, pil);
		prom_halt();
	}
	imap += reg_base;

	/* SYSIO inconsistancy.  For external SLOTS, we have to select
	 * the right ICLR register based upon the lower SBUS irq level
	 * bits.
	 */
	if (ino >= 0x20) {
		iclr = sysio_imap_to_iclr(imap);
	} else {
		int sbus_slot = (ino & 0x18)>>3;
		
		sbus_level = ino & 0x7;

		switch(sbus_slot) {
		case 0:
			iclr = reg_base + SYSIO_ICLR_SLOT0;
			break;
		case 1:
			iclr = reg_base + SYSIO_ICLR_SLOT1;
			break;
		case 2:
			iclr = reg_base + SYSIO_ICLR_SLOT2;
			break;
		default:
		case 3:
			iclr = reg_base + SYSIO_ICLR_SLOT3;
			break;
		};

		iclr += ((unsigned long)sbus_level - 1UL) * 8UL;
	}
	return build_irq(pil, sbus_level, iclr, imap);
}

/* Error interrupt handling. */
#define SYSIO_UE_AFSR	0x0030UL
#define SYSIO_UE_AFAR	0x0038UL
#define  SYSIO_UEAFSR_PPIO	0x8000000000000000 /* Primary PIO is cause         */
#define  SYSIO_UEAFSR_PDRD	0x4000000000000000 /* Primary DVMA read is cause   */
#define  SYSIO_UEAFSR_PDWR	0x2000000000000000 /* Primary DVMA write is cause  */
#define  SYSIO_UEAFSR_SPIO	0x1000000000000000 /* Secondary PIO is cause       */
#define  SYSIO_UEAFSR_SDRD	0x0800000000000000 /* Secondary DVMA read is cause */
#define  SYSIO_UEAFSR_SDWR	0x0400000000000000 /* Secondary DVMA write is cause*/
#define  SYSIO_UEAFSR_RESV1	0x03ff000000000000 /* Reserved                     */
#define  SYSIO_UEAFSR_DOFF	0x0000e00000000000 /* Doubleword Offset            */
#define  SYSIO_UEAFSR_SIZE	0x00001c0000000000 /* Bad transfer size is 2**SIZE */
#define  SYSIO_UEAFSR_MID	0x000003e000000000 /* UPA MID causing the fault    */
#define  SYSIO_UEAFSR_RESV2	0x0000001fffffffff /* Reserved                     */
static void sysio_ue_handler(int irq, void *dev_id, struct pt_regs *regs)
{
	struct sbus_bus *sbus = dev_id;
	struct sbus_iommu *iommu = sbus->iommu;
	unsigned long reg_base = iommu->sbus_control_reg - 0x2000UL;
	unsigned long afsr_reg, afar_reg;
	unsigned long afsr, afar, error_bits;
	int reported;

	afsr_reg = reg_base + SYSIO_UE_AFSR;
	afar_reg = reg_base + SYSIO_UE_AFAR;

	/* Latch error status. */
	afsr = upa_readq(afsr_reg);
	afar = upa_readq(afar_reg);

	/* Clear primary/secondary error status bits. */
	error_bits = afsr &
		(SYSIO_UEAFSR_PPIO | SYSIO_UEAFSR_PDRD | SYSIO_UEAFSR_PDWR |
		 SYSIO_UEAFSR_SPIO | SYSIO_UEAFSR_SDRD | SYSIO_UEAFSR_SDWR);
	upa_writeq(error_bits, afsr_reg);

	/* Log the error. */
	printk("SYSIO[%x]: Uncorrectable ECC Error, primary error type[%s]\n",
	       sbus->portid,
	       (((error_bits & SYSIO_UEAFSR_PPIO) ?
		 "PIO" :
		 ((error_bits & SYSIO_UEAFSR_PDRD) ?
		  "DVMA Read" :
		  ((error_bits & SYSIO_UEAFSR_PDWR) ?
		   "DVMA Write" : "???")))));
	printk("SYSIO[%x]: DOFF[%lx] SIZE[%lx] MID[%lx]\n",
	       sbus->portid,
	       (afsr & SYSIO_UEAFSR_DOFF) >> 45UL,
	       (afsr & SYSIO_UEAFSR_SIZE) >> 42UL,
	       (afsr & SYSIO_UEAFSR_MID) >> 37UL);
	printk("SYSIO[%x]: AFAR[%016lx]\n", sbus->portid, afar);
	printk("SYSIO[%x]: Secondary UE errors [", sbus->portid);
	reported = 0;
	if (afsr & SYSIO_UEAFSR_SPIO) {
		reported++;
		printk("(PIO)");
	}
	if (afsr & SYSIO_UEAFSR_SDRD) {
		reported++;
		printk("(DVMA Read)");
	}
	if (afsr & SYSIO_UEAFSR_SDWR) {
		reported++;
		printk("(DVMA Write)");
	}
	if (!reported)
		printk("(none)");
	printk("]\n");
}

#define SYSIO_CE_AFSR	0x0040UL
#define SYSIO_CE_AFAR	0x0048UL
#define  SYSIO_CEAFSR_PPIO	0x8000000000000000 /* Primary PIO is cause         */
#define  SYSIO_CEAFSR_PDRD	0x4000000000000000 /* Primary DVMA read is cause   */
#define  SYSIO_CEAFSR_PDWR	0x2000000000000000 /* Primary DVMA write is cause  */
#define  SYSIO_CEAFSR_SPIO	0x1000000000000000 /* Secondary PIO is cause       */
#define  SYSIO_CEAFSR_SDRD	0x0800000000000000 /* Secondary DVMA read is cause */
#define  SYSIO_CEAFSR_SDWR	0x0400000000000000 /* Secondary DVMA write is cause*/
#define  SYSIO_CEAFSR_RESV1	0x0300000000000000 /* Reserved                     */
#define  SYSIO_CEAFSR_ESYND	0x00ff000000000000 /* Syndrome Bits                */
#define  SYSIO_CEAFSR_DOFF	0x0000e00000000000 /* Double Offset                */
#define  SYSIO_CEAFSR_SIZE	0x00001c0000000000 /* Bad transfer size is 2**SIZE */
#define  SYSIO_CEAFSR_MID	0x000003e000000000 /* UPA MID causing the fault    */
#define  SYSIO_CEAFSR_RESV2	0x0000001fffffffff /* Reserved                     */
static void sysio_ce_handler(int irq, void *dev_id, struct pt_regs *regs)
{
	struct sbus_bus *sbus = dev_id;
	struct sbus_iommu *iommu = sbus->iommu;
	unsigned long reg_base = iommu->sbus_control_reg - 0x2000UL;
	unsigned long afsr_reg, afar_reg;
	unsigned long afsr, afar, error_bits;
	int reported;

	afsr_reg = reg_base + SYSIO_CE_AFSR;
	afar_reg = reg_base + SYSIO_CE_AFAR;

	/* Latch error status. */
	afsr = upa_readq(afsr_reg);
	afar = upa_readq(afar_reg);

	/* Clear primary/secondary error status bits. */
	error_bits = afsr &
		(SYSIO_CEAFSR_PPIO | SYSIO_CEAFSR_PDRD | SYSIO_CEAFSR_PDWR |
		 SYSIO_CEAFSR_SPIO | SYSIO_CEAFSR_SDRD | SYSIO_CEAFSR_SDWR);
	upa_writeq(error_bits, afsr_reg);

	printk("SYSIO[%x]: Correctable ECC Error, primary error type[%s]\n",
	       sbus->portid,
	       (((error_bits & SYSIO_CEAFSR_PPIO) ?
		 "PIO" :
		 ((error_bits & SYSIO_CEAFSR_PDRD) ?
		  "DVMA Read" :
		  ((error_bits & SYSIO_CEAFSR_PDWR) ?
		   "DVMA Write" : "???")))));

	/* XXX Use syndrome and afar to print out module string just like
	 * XXX UDB CE trap handler does... -DaveM
	 */
	printk("SYSIO[%x]: DOFF[%lx] ECC Syndrome[%lx] Size[%lx] MID[%lx]\n",
	       sbus->portid,
	       (afsr & SYSIO_CEAFSR_DOFF) >> 45UL,
	       (afsr & SYSIO_CEAFSR_ESYND) >> 48UL,
	       (afsr & SYSIO_CEAFSR_SIZE) >> 42UL,
	       (afsr & SYSIO_CEAFSR_MID) >> 37UL);
	printk("SYSIO[%x]: AFAR[%016lx]\n", sbus->portid, afar);

	printk("SYSIO[%x]: Secondary CE errors [", sbus->portid);
	reported = 0;
	if (afsr & SYSIO_CEAFSR_SPIO) {
		reported++;
		printk("(PIO)");
	}
	if (afsr & SYSIO_CEAFSR_SDRD) {
		reported++;
		printk("(DVMA Read)");
	}
	if (afsr & SYSIO_CEAFSR_SDWR) {
		reported++;
		printk("(DVMA Write)");
	}
	if (!reported)
		printk("(none)");
	printk("]\n");
}

#define SYSIO_SBUS_AFSR		0x2010UL
#define SYSIO_SBUS_AFAR		0x2018UL
#define  SYSIO_SBAFSR_PLE	0x8000000000000000 /* Primary Late PIO Error       */
#define  SYSIO_SBAFSR_PTO	0x4000000000000000 /* Primary SBUS Timeout         */
#define  SYSIO_SBAFSR_PBERR	0x2000000000000000 /* Primary SBUS Error ACK       */
#define  SYSIO_SBAFSR_SLE	0x1000000000000000 /* Secondary Late PIO Error     */
#define  SYSIO_SBAFSR_STO	0x0800000000000000 /* Secondary SBUS Timeout       */
#define  SYSIO_SBAFSR_SBERR	0x0400000000000000 /* Secondary SBUS Error ACK     */
#define  SYSIO_SBAFSR_RESV1	0x03ff000000000000 /* Reserved                     */
#define  SYSIO_SBAFSR_RD	0x0000800000000000 /* Primary was late PIO read    */
#define  SYSIO_SBAFSR_RESV2	0x0000600000000000 /* Reserved                     */
#define  SYSIO_SBAFSR_SIZE	0x00001c0000000000 /* Size of transfer             */
#define  SYSIO_SBAFSR_MID	0x000003e000000000 /* MID causing the error        */
#define  SYSIO_SBAFSR_RESV3	0x0000001fffffffff /* Reserved                     */
static void sysio_sbus_error_handler(int irq, void *dev_id, struct pt_regs *regs)
{
	struct sbus_bus *sbus = dev_id;
	struct sbus_iommu *iommu = sbus->iommu;
	unsigned long afsr_reg, afar_reg, reg_base;
	unsigned long afsr, afar, error_bits;
	int reported;

	reg_base = iommu->sbus_control_reg - 0x2000UL;
	afsr_reg = reg_base + SYSIO_SBUS_AFSR;
	afar_reg = reg_base + SYSIO_SBUS_AFAR;

	afsr = upa_readq(afsr_reg);
	afar = upa_readq(afar_reg);

	/* Clear primary/secondary error status bits. */
	error_bits = afsr &
		(SYSIO_SBAFSR_PLE | SYSIO_SBAFSR_PTO | SYSIO_SBAFSR_PBERR |
		 SYSIO_SBAFSR_SLE | SYSIO_SBAFSR_STO | SYSIO_SBAFSR_SBERR);
	upa_writeq(error_bits, afsr_reg);

	/* Log the error. */
	printk("SYSIO[%x]: SBUS Error, primary error type[%s] read(%d)\n",
	       sbus->portid,
	       (((error_bits & SYSIO_SBAFSR_PLE) ?
		 "Late PIO Error" :
		 ((error_bits & SYSIO_SBAFSR_PTO) ?
		  "Time Out" :
		  ((error_bits & SYSIO_SBAFSR_PBERR) ?
		   "Error Ack" : "???")))),
	       (afsr & SYSIO_SBAFSR_RD) ? 1 : 0);
	printk("SYSIO[%x]: size[%lx] MID[%lx]\n",
	       sbus->portid,
	       (afsr & SYSIO_SBAFSR_SIZE) >> 42UL,
	       (afsr & SYSIO_SBAFSR_MID) >> 37UL);
	printk("SYSIO[%x]: AFAR[%016lx]\n", sbus->portid, afar);
	printk("SYSIO[%x]: Secondary SBUS errors [", sbus->portid);
	reported = 0;
	if (afsr & SYSIO_SBAFSR_SLE) {
		reported++;
		printk("(Late PIO Error)");
	}
	if (afsr & SYSIO_SBAFSR_STO) {
		reported++;
		printk("(Time Out)");
	}
	if (afsr & SYSIO_SBAFSR_SBERR) {
		reported++;
		printk("(Error Ack)");
	}
	if (!reported)
		printk("(none)");
	printk("]\n");

	/* XXX check iommu/strbuf for further error status XXX */
}

#define ECC_CONTROL	0x0020UL
#define  SYSIO_ECNTRL_ECCEN	0x8000000000000000 /* Enable ECC Checking          */
#define  SYSIO_ECNTRL_UEEN	0x4000000000000000 /* Enable UE Interrupts         */
#define  SYSIO_ECNTRL_CEEN	0x2000000000000000 /* Enable CE Interrupts         */

#define SYSIO_UE_INO		0x34
#define SYSIO_CE_INO		0x35
#define SYSIO_SBUSERR_INO	0x36

static void __init sysio_register_error_handlers(struct sbus_bus *sbus)
{
	struct sbus_iommu *iommu = sbus->iommu;
	unsigned long reg_base = iommu->sbus_control_reg - 0x2000UL;
	unsigned int irq;
	u64 control;

	irq = sbus_build_irq(sbus, SYSIO_UE_INO);
	if (request_irq(irq, sysio_ue_handler,
			SA_SHIRQ, "SYSIO UE", sbus) < 0) {
		prom_printf("SYSIO[%x]: Cannot register UE interrupt.\n",
			    sbus->portid);
		prom_halt();
	}

	irq = sbus_build_irq(sbus, SYSIO_CE_INO);
	if (request_irq(irq, sysio_ce_handler,
			SA_SHIRQ, "SYSIO CE", sbus) < 0) {
		prom_printf("SYSIO[%x]: Cannot register CE interrupt.\n",
			    sbus->portid);
		prom_halt();
	}

	irq = sbus_build_irq(sbus, SYSIO_SBUSERR_INO);
	if (request_irq(irq, sysio_sbus_error_handler,
			SA_SHIRQ, "SYSIO SBUS Error", sbus) < 0) {
		prom_printf("SYSIO[%x]: Cannot register SBUS Error interrupt.\n",
			    sbus->portid);
		prom_halt();
	}

	/* Now turn the error interrupts on and also enable ECC checking. */
	upa_writeq((SYSIO_ECNTRL_ECCEN |
		    SYSIO_ECNTRL_UEEN  |
		    SYSIO_ECNTRL_CEEN),
		   reg_base + ECC_CONTROL);

	control = upa_readq(iommu->sbus_control_reg);
	control |= 0x100UL; /* SBUS Error Interrupt Enable */
	upa_writeq(control, iommu->sbus_control_reg);
}

/* Boot time initialization. */
void __init sbus_iommu_init(int prom_node, struct sbus_bus *sbus)
{
	struct linux_prom64_registers rprop;
	struct sbus_iommu *iommu;
	unsigned long regs, tsb_base;
	u64 control;
	int err, i;

	sbus->portid = prom_getintdefault(sbus->prom_node,
					  "upa-portid", -1);

	err = prom_getproperty(prom_node, "reg",
			       (char *)&rprop, sizeof(rprop));
	if (err < 0) {
		prom_printf("sbus_iommu_init: Cannot map SYSIO control registers.\n");
		prom_halt();
	}
	regs = rprop.phys_addr;

	iommu = kmalloc(sizeof(*iommu) + SMP_CACHE_BYTES, GFP_ATOMIC);
	if (iommu == NULL) {
		prom_printf("sbus_iommu_init: Fatal error, kmalloc(iommu) failed\n");
		prom_halt();
	}

	/* Align on E$ line boundry. */
	iommu = (struct sbus_iommu *)
		(((unsigned long)iommu + (SMP_CACHE_BYTES - 1UL)) &
		 ~(SMP_CACHE_BYTES - 1UL));

	memset(iommu, 0, sizeof(*iommu));

	/* Setup spinlock. */
	spin_lock_init(&iommu->lock);

	/* Init register offsets. */
	iommu->iommu_regs = regs + SYSIO_IOMMUREG_BASE;
	iommu->strbuf_regs = regs + SYSIO_STRBUFREG_BASE;

	/* The SYSIO SBUS control register is used for dummy reads
	 * in order to ensure write completion.
	 */
	iommu->sbus_control_reg = regs + 0x2000UL;

	/* Link into SYSIO software state. */
	sbus->iommu = iommu;

	printk("SYSIO: UPA portID %x, at %016lx\n",
	       sbus->portid, regs);

	/* Setup for TSB_SIZE=7, TBW_SIZE=0, MMU_DE=1, MMU_EN=1 */
	control = upa_readq(iommu->iommu_regs + IOMMU_CONTROL);
	control = ((7UL << 16UL)	|
		   (0UL << 2UL)		|
		   (1UL << 1UL)		|
		   (1UL << 0UL));

	/* Using the above configuration we need 1MB iommu page
	 * table (128K ioptes * 8 bytes per iopte).  This is
	 * page order 7 on UltraSparc.
	 */
	tsb_base = __get_free_pages(GFP_ATOMIC, 7);
	if (tsb_base == 0UL) {
		prom_printf("sbus_iommu_init: Fatal error, cannot alloc TSB table.\n");
		prom_halt();
	}

	iommu->page_table = (iopte_t *) tsb_base;
	memset(iommu->page_table, 0, (PAGE_SIZE << 7));

	upa_writeq(control, iommu->iommu_regs + IOMMU_CONTROL);

	/* Clean out any cruft in the IOMMU using
	 * diagnostic accesses.
	 */
	for (i = 0; i < 16; i++) {
		unsigned long dram = iommu->iommu_regs + IOMMU_DRAMDIAG;

		dram += (unsigned long)i * 8UL;
		upa_writeq(0, dram);
	}
	upa_readq(iommu->sbus_control_reg);

	/* Give the TSB to SYSIO. */
	upa_writeq(__pa(tsb_base), iommu->iommu_regs + IOMMU_TSBBASE);

	/* Setup streaming buffer, DE=1 SB_EN=1 */
	control = (1UL << 1UL) | (1UL << 0UL);
	upa_writeq(control, iommu->strbuf_regs + STRBUF_CONTROL);

	/* Clear out the tags using diagnostics. */
	for (i = 0; i < 16; i++) {
		unsigned long ptag, ltag;

		ptag = iommu->strbuf_regs + STRBUF_PTAGDIAG;
		ltag = iommu->strbuf_regs + STRBUF_LTAGDIAG;
		ptag += (unsigned long)i * 8UL;
		ltag += (unsigned long)i * 8UL;

		upa_writeq(0UL, ptag);
		upa_writeq(0UL, ltag);
	}

	/* Enable DVMA arbitration for all devices/slots. */
	control = upa_readq(iommu->sbus_control_reg);
	control |= 0x3fUL;
	upa_writeq(control, iommu->sbus_control_reg);

	/* Now some Xfire specific grot... */
	{
		extern void *starfire_hookup(int);
		extern int this_is_starfire;

		if (this_is_starfire)
			sbus->starfire_cookie = starfire_hookup(sbus->portid);
		else
			sbus->starfire_cookie = NULL;
	}

	sysio_register_error_handlers(sbus);
}