/* $Id: io-unit.c,v 1.24 2001/12/17 07:05:09 davem Exp $ * io-unit.c:  IO-UNIT specific routines for memory management. * * Copyright (C) 1997,1998 Jakub Jelinek    (jj@sunsite.mff.cuni.cz) */ #include <linux/config.h>#include <linux/kernel.h>#include <linux/init.h>#include <linux/slab.h>#include <linux/spinlock.h>#include <linux/mm.h>#include <linux/highmem.h>	/* pte_offset_map => kmap_atomic */#include <linux/bitops.h>#include <asm/scatterlist.h>#include <asm/pgalloc.h>#include <asm/pgtable.h>#include <asm/sbus.h>#include <asm/io.h>#include <asm/io-unit.h>#include <asm/mxcc.h>#include <asm/cacheflush.h>#include <asm/tlbflush.h>#include <asm/dma.h>/* #define IOUNIT_DEBUG */#ifdef IOUNIT_DEBUG#define IOD(x) printk(x)#else#define IOD(x) do { } while (0)#endif#define IOPERM        (IOUPTE_CACHE | IOUPTE_WRITE | IOUPTE_VALID)#define MKIOPTE(phys) __iopte((((phys)>>4) & IOUPTE_PAGE) | IOPERM)void __initiounit_init(int sbi_node, int io_node, struct sbus_bus *sbus){	iopte_t *xpt, *xptend;	struct iounit_struct *iounit;	struct linux_prom_registers iommu_promregs[PROMREG_MAX];	struct resource r;	iounit = kmalloc(sizeof(struct iounit_struct), GFP_ATOMIC);	memset(iounit, 0, sizeof(*iounit));	iounit->limit[0] = IOUNIT_BMAP1_START;	iounit->limit[1] = IOUNIT_BMAP2_START;	iounit->limit[2] = IOUNIT_BMAPM_START;	iounit->limit[3] = IOUNIT_BMAPM_END;	iounit->rotor[1] = IOUNIT_BMAP2_START;	iounit->rotor[2] = IOUNIT_BMAPM_START;	xpt = NULL;	if(prom_getproperty(sbi_node, "reg", (void *) iommu_promregs,			    sizeof(iommu_promregs)) != -1) {		prom_apply_generic_ranges(io_node, 0, iommu_promregs, 3);		memset(&r, 0, sizeof(r));		r.flags = iommu_promregs[2].which_io;		r.start = iommu_promregs[2].phys_addr;		xpt = (iopte_t *) sbus_ioremap(&r, 0, PAGE_SIZE * 16, "XPT");	}	if(!xpt) panic("Cannot map External Page Table.");		sbus->iommu = (struct iommu_struct *)iounit;	iounit->page_table = xpt;		for (xptend = iounit->page_table + (16 * PAGE_SIZE) / sizeof(iopte_t);	     xpt < xptend;)	     	iopte_val(*xpt++) = 0;}/* One has to hold iounit->lock to call this */static unsigned long iounit_get_area(struct iounit_struct *iounit, unsigned long vaddr, int size){	int i, j, k, npages;	unsigned long rotor, scan, limit;	iopte_t iopte;        npages = ((vaddr & ~PAGE_MASK) + size + (PAGE_SIZE-1)) >> PAGE_SHIFT;	/* A tiny bit of magic ingredience :) */	switch (npages) {	case 1: i = 0x0231; break;	case 2: i = 0x0132; break;	default: i = 0x0213; break;	}		IOD(("iounit_get_area(%08lx,%d[%d])=", vaddr, size, npages));	next:	j = (i & 15);	rotor = iounit->rotor[j - 1];	limit = iounit->limit[j];	scan = rotor;nexti:	scan = find_next_zero_bit(iounit->bmap, limit, scan);	if (scan + npages > limit) {		if (limit != rotor) {			limit = rotor;			scan = iounit->limit[j - 1];			goto nexti;		}		i >>= 4;		if (!(i & 15))			panic("iounit_get_area: Couldn't find free iopte slots for (%08lx,%d)\n", vaddr, size);		goto next;	}	for (k = 1, scan++; k < npages; k++)		if (test_bit(scan++, iounit->bmap))			goto nexti;	iounit->rotor[j - 1] = (scan < limit) ? scan : iounit->limit[j - 1];	scan -= npages;	iopte = MKIOPTE(__pa(vaddr & PAGE_MASK));	vaddr = IOUNIT_DMA_BASE + (scan << PAGE_SHIFT) + (vaddr & ~PAGE_MASK);	for (k = 0; k < npages; k++, iopte = __iopte(iopte_val(iopte) + 0x100), scan++) {		set_bit(scan, iounit->bmap);		iounit->page_table[scan] = iopte;	}	IOD(("%08lx\n", vaddr));	return vaddr;}static __u32 iounit_get_scsi_one(char *vaddr, unsigned long len, struct sbus_bus *sbus){	unsigned long ret, flags;	struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;		spin_lock_irqsave(&iounit->lock, flags);	ret = iounit_get_area(iounit, (unsigned long)vaddr, len);	spin_unlock_irqrestore(&iounit->lock, flags);	return ret;}static void iounit_get_scsi_sgl(struct scatterlist *sg, int sz, struct sbus_bus *sbus){	unsigned long flags;	struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;	/* FIXME: Cache some resolved pages - often several sg entries are to the same page */	spin_lock_irqsave(&iounit->lock, flags);	while (sz != 0) {		--sz;		sg[sz].dvma_address = iounit_get_area(iounit, (unsigned long)page_address(sg[sz].page) + sg[sz].offset, sg[sz].length);		sg[sz].dvma_length = sg[sz].length;	}	spin_unlock_irqrestore(&iounit->lock, flags);}static void iounit_release_scsi_one(__u32 vaddr, unsigned long len, struct sbus_bus *sbus){	unsigned long flags;	struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;		spin_lock_irqsave(&iounit->lock, flags);	len = ((vaddr & ~PAGE_MASK) + len + (PAGE_SIZE-1)) >> PAGE_SHIFT;	vaddr = (vaddr - IOUNIT_DMA_BASE) >> PAGE_SHIFT;	IOD(("iounit_release %08lx-%08lx\n", (long)vaddr, (long)len+vaddr));	for (len += vaddr; vaddr < len; vaddr++)		clear_bit(vaddr, iounit->bmap);	spin_unlock_irqrestore(&iounit->lock, flags);}static void iounit_release_scsi_sgl(struct scatterlist *sg, int sz, struct sbus_bus *sbus){	unsigned long flags;	unsigned long vaddr, len;	struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;	spin_lock_irqsave(&iounit->lock, flags);	while (sz != 0) {		--sz;		len = ((sg[sz].dvma_address & ~PAGE_MASK) + sg[sz].length + (PAGE_SIZE-1)) >> PAGE_SHIFT;		vaddr = (sg[sz].dvma_address - IOUNIT_DMA_BASE) >> PAGE_SHIFT;		IOD(("iounit_release %08lx-%08lx\n", (long)vaddr, (long)len+vaddr));		for (len += vaddr; vaddr < len; vaddr++)			clear_bit(vaddr, iounit->bmap);	}	spin_unlock_irqrestore(&iounit->lock, flags);}#ifdef CONFIG_SBUSstatic int iounit_map_dma_area(dma_addr_t *pba, unsigned long va, __u32 addr, int len){	unsigned long page, end;	pgprot_t dvma_prot;	iopte_t *iopte;	struct sbus_bus *sbus;	*pba = addr;	dvma_prot = __pgprot(SRMMU_CACHE | SRMMU_ET_PTE | SRMMU_PRIV);	end = PAGE_ALIGN((addr + len));	while(addr < end) {		page = va;		{			pgd_t *pgdp;			pmd_t *pmdp;			pte_t *ptep;			long i;			pgdp = pgd_offset(&init_mm, addr);			pmdp = pmd_offset(pgdp, addr);			ptep = pte_offset_map(pmdp, addr);			set_pte(ptep, mk_pte(virt_to_page(page), dvma_prot));						i = ((addr - IOUNIT_DMA_BASE) >> PAGE_SHIFT);			for_each_sbus(sbus) {				struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;				iopte = (iopte_t *)(iounit->page_table + i);				*iopte = MKIOPTE(__pa(page));			}		}		addr += PAGE_SIZE;		va += PAGE_SIZE;	}	flush_cache_all();	flush_tlb_all();	return 0;}static void iounit_unmap_dma_area(unsigned long addr, int len){	/* XXX Somebody please fill this in */}/* XXX We do not pass sbus device here, bad. */static struct page *iounit_translate_dvma(unsigned long addr){	struct sbus_bus *sbus = sbus_root;	/* They are all the same */	struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;	int i;	iopte_t *iopte;	i = ((addr - IOUNIT_DMA_BASE) >> PAGE_SHIFT);	iopte = (iopte_t *)(iounit->page_table + i);	return pfn_to_page(iopte_val(*iopte) >> (PAGE_SHIFT-4)); /* XXX sun4d guru, help */}#endifstatic char *iounit_lockarea(char *vaddr, unsigned long len){/* FIXME: Write this */	return vaddr;}static void iounit_unlockarea(char *vaddr, unsigned long len){/* FIXME: Write this */}void __init ld_mmu_iounit(void){	BTFIXUPSET_CALL(mmu_lockarea, iounit_lockarea, BTFIXUPCALL_RETO0);	BTFIXUPSET_CALL(mmu_unlockarea, iounit_unlockarea, BTFIXUPCALL_NOP);	BTFIXUPSET_CALL(mmu_get_scsi_one, iounit_get_scsi_one, BTFIXUPCALL_NORM);	BTFIXUPSET_CALL(mmu_get_scsi_sgl, iounit_get_scsi_sgl, BTFIXUPCALL_NORM);	BTFIXUPSET_CALL(mmu_release_scsi_one, iounit_release_scsi_one, BTFIXUPCALL_NORM);	BTFIXUPSET_CALL(mmu_release_scsi_sgl, iounit_release_scsi_sgl, BTFIXUPCALL_NORM);#ifdef CONFIG_SBUS	BTFIXUPSET_CALL(mmu_map_dma_area, iounit_map_dma_area, BTFIXUPCALL_NORM);	BTFIXUPSET_CALL(mmu_unmap_dma_area, iounit_unmap_dma_area, BTFIXUPCALL_NORM);	BTFIXUPSET_CALL(mmu_translate_dvma, iounit_translate_dvma, BTFIXUPCALL_NORM);#endif}__u32 iounit_map_dma_init(struct sbus_bus *sbus, int size){	int i, j, k, npages;	unsigned long rotor, scan, limit;	unsigned long flags;	__u32 ret;	struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;        npages = (size + (PAGE_SIZE-1)) >> PAGE_SHIFT;	i = 0x0213;	spin_lock_irqsave(&iounit->lock, flags);next:	j = (i & 15);	rotor = iounit->rotor[j - 1];	limit = iounit->limit[j];	scan = rotor;nexti:	scan = find_next_zero_bit(iounit->bmap, limit, scan);	if (scan + npages > limit) {		if (limit != rotor) {			limit = rotor;			scan = iounit->limit[j - 1];			goto nexti;		}		i >>= 4;		if (!(i & 15))			panic("iounit_map_dma_init: Couldn't find free iopte slots for %d bytes\n", size);		goto next;	}	for (k = 1, scan++; k < npages; k++)		if (test_bit(scan++, iounit->bmap))			goto nexti;	iounit->rotor[j - 1] = (scan < limit) ? scan : iounit->limit[j - 1];	scan -= npages;	ret = IOUNIT_DMA_BASE + (scan << PAGE_SHIFT);	for (k = 0; k < npages; k++, scan++)		set_bit(scan, iounit->bmap);	spin_unlock_irqrestore(&iounit->lock, flags);	return ret;}__u32 iounit_map_dma_page(__u32 vaddr, void *addr, struct sbus_bus *sbus){	int scan = (vaddr - IOUNIT_DMA_BASE) >> PAGE_SHIFT;	struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;		iounit->page_table[scan] = MKIOPTE(__pa(((unsigned long)addr) & PAGE_MASK));	return vaddr + (((unsigned long)addr) & ~PAGE_MASK);}