/*  $Id: init.c,v 1.209 2002/02/09 19:49:31 davem Exp $
 *  arch/sparc64/mm/init.c
 *
 *  Copyright (C) 1996-1999 David S. Miller (davem@caip.rutgers.edu)
 *  Copyright (C) 1997-1999 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
 */
 
#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/bootmem.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/blk.h>
#include <linux/swap.h>
#include <linux/swapctl.h>
#include <linux/pagemap.h>
#include <linux/fs.h>
#include <linux/seq_file.h>

#include <asm/head.h>
#include <asm/system.h>
#include <asm/page.h>
#include <asm/pgalloc.h>
#include <asm/pgtable.h>
#include <asm/oplib.h>
#include <asm/iommu.h>
#include <asm/io.h>
#include <asm/uaccess.h>
#include <asm/mmu_context.h>
#include <asm/dma.h>
#include <asm/starfire.h>
#include <asm/tlb.h>
#include <asm/spitfire.h>

mmu_gather_t mmu_gathers[NR_CPUS];

extern void device_scan(void);

struct sparc_phys_banks sp_banks[SPARC_PHYS_BANKS];

unsigned long *sparc64_valid_addr_bitmap;

/* Ugly, but necessary... -DaveM */
unsigned long phys_base;

enum ultra_tlb_layout tlb_type = spitfire;

/* get_new_mmu_context() uses "cache + 1".  */
spinlock_t ctx_alloc_lock = SPIN_LOCK_UNLOCKED;
unsigned long tlb_context_cache = CTX_FIRST_VERSION - 1;
#define CTX_BMAP_SLOTS (1UL << (CTX_VERSION_SHIFT - 6))
unsigned long mmu_context_bmap[CTX_BMAP_SLOTS];

/* References to section boundaries */
extern char __init_begin, __init_end, _start, _end, etext, edata;

/* Initial ramdisk setup */
extern unsigned int sparc_ramdisk_image;
extern unsigned int sparc_ramdisk_size;

struct page *mem_map_zero;

int bigkernel = 0;

/* XXX Tune this... */
#define PGT_CACHE_LOW	25
#define PGT_CACHE_HIGH	50

void check_pgt_cache(void)
{
	preempt_disable();
	if (pgtable_cache_size > PGT_CACHE_HIGH) {
		do {
#ifdef CONFIG_SMP
			if (pgd_quicklist)
				free_pgd_slow(get_pgd_fast());
#endif
			if (pte_quicklist[0])
				free_pte_slow(pte_alloc_one_fast(NULL, 0));
			if (pte_quicklist[1])
				free_pte_slow(pte_alloc_one_fast(NULL, 1 << (PAGE_SHIFT + 10)));
		} while (pgtable_cache_size > PGT_CACHE_LOW);
	}
#ifndef CONFIG_SMP
        if (pgd_cache_size > PGT_CACHE_HIGH / 4) {
		struct page *page, *page2;
                for (page2 = NULL, page = (struct page *)pgd_quicklist; page;) {
                        if ((unsigned long)page->pprev_hash == 3) {
                                if (page2)
                                        page2->next_hash = page->next_hash;
                                else
                                        (struct page *)pgd_quicklist = page->next_hash;
                                page->next_hash = NULL;
                                page->pprev_hash = NULL;
                                pgd_cache_size -= 2;
                                __free_page(page);
                                if (page2)
                                        page = page2->next_hash;
                                else
                                        page = (struct page *)pgd_quicklist;
                                if (pgd_cache_size <= PGT_CACHE_LOW / 4)
                                        break;
                                continue;
                        }
                        page2 = page;
                        page = page->next_hash;
                }
        }
#endif
	preempt_enable();
}

#ifdef CONFIG_DEBUG_DCFLUSH
atomic_t dcpage_flushes = ATOMIC_INIT(0);
#ifdef CONFIG_SMP
atomic_t dcpage_flushes_xcall = ATOMIC_INIT(0);
#endif
#endif

__inline__ void flush_dcache_page_impl(struct page *page)
{
#ifdef CONFIG_DEBUG_DCFLUSH
	atomic_inc(&dcpage_flushes);
#endif

#if (L1DCACHE_SIZE > PAGE_SIZE)
	__flush_dcache_page(page->virtual,
			    ((tlb_type == spitfire) &&
			     page->mapping != NULL));
#else
	if (page->mapping != NULL &&
	    tlb_type == spitfire)
		__flush_icache_page(__pa(page->virtual));
#endif
}

#define PG_dcache_dirty		PG_arch_1

#define dcache_dirty_cpu(page) \
	(((page)->flags >> 24) & (NR_CPUS - 1UL))

static __inline__ void set_dcache_dirty(struct page *page)
{
	unsigned long mask = smp_processor_id();
	unsigned long non_cpu_bits = ~((NR_CPUS - 1UL) << 24UL);
	mask = (mask << 24) | (1UL << PG_dcache_dirty);
	__asm__ __volatile__("1:\n\t"
			     "ldx	[%2], %%g7\n\t"
			     "and	%%g7, %1, %%g5\n\t"
			     "or	%%g5, %0, %%g5\n\t"
			     "casx	[%2], %%g7, %%g5\n\t"
			     "cmp	%%g7, %%g5\n\t"
			     "bne,pn	%%xcc, 1b\n\t"
			     " membar	#StoreLoad | #StoreStore"
			     : /* no outputs */
			     : "r" (mask), "r" (non_cpu_bits), "r" (&page->flags)
			     : "g5", "g7");
}

static __inline__ void clear_dcache_dirty_cpu(struct page *page, unsigned long cpu)
{
	unsigned long mask = (1UL << PG_dcache_dirty);

	__asm__ __volatile__("! test_and_clear_dcache_dirty\n"
			     "1:\n\t"
			     "ldx	[%2], %%g7\n\t"
			     "srlx	%%g7, 24, %%g5\n\t"
			     "and	%%g5, %3, %%g5\n\t"
			     "cmp	%%g5, %0\n\t"
			     "bne,pn	%%icc, 2f\n\t"
			     " andn	%%g7, %1, %%g5\n\t"
			     "casx	[%2], %%g7, %%g5\n\t"
			     "cmp	%%g7, %%g5\n\t"
			     "bne,pn	%%xcc, 1b\n\t"
			     " membar	#StoreLoad | #StoreStore\n"
			     "2:"
			     : /* no outputs */
			     : "r" (cpu), "r" (mask), "r" (&page->flags),
			       "i" (NR_CPUS - 1UL)
			     : "g5", "g7");
}

extern void __update_mmu_cache(unsigned long mmu_context_hw, unsigned long address, pte_t pte, int code);

void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, pte_t pte)
{
	struct page *page = pte_page(pte);
	unsigned long pg_flags;

	if (VALID_PAGE(page) &&
	    page->mapping &&
	    ((pg_flags = page->flags) & (1UL << PG_dcache_dirty))) {
		int cpu = ((pg_flags >> 24) & (NR_CPUS - 1UL));

		/* This is just to optimize away some function calls
		 * in the SMP case.
		 */
		if (cpu == smp_processor_id())
			flush_dcache_page_impl(page);
		else
			smp_flush_dcache_page_impl(page, cpu);

		clear_dcache_dirty_cpu(page, cpu);
	}
	if (get_thread_fault_code())
		__update_mmu_cache(vma->vm_mm->context & TAG_CONTEXT_BITS,
				   address, pte, get_thread_fault_code());
}

void flush_dcache_page(struct page *page)
{
	int dirty = test_bit(PG_dcache_dirty, &page->flags);
	int dirty_cpu = dcache_dirty_cpu(page);

	if (page->mapping &&
	    list_empty(&page->mapping->i_mmap) &&
	    list_empty(&page->mapping->i_mmap_shared)) {
		if (dirty) {
			if (dirty_cpu == smp_processor_id())
				return;
			smp_flush_dcache_page_impl(page, dirty_cpu);
		}
		set_dcache_dirty(page);
	} else {
		/* We could delay the flush for the !page->mapping
		 * case too.  But that case is for exec env/arg
		 * pages and those are %99 certainly going to get
		 * faulted into the tlb (and thus flushed) anyways.
		 */
		flush_dcache_page_impl(page);
	}
}

/* When shared+writable mmaps of files go away, we lose all dirty
 * page state, so we have to deal with D-cache aliasing here.
 *
 * This code relies on the fact that flush_cache_range() is always
 * called for an area composed by a single VMA.  It also assumes that
 * the MM's page_table_lock is held.
 */
static inline void flush_cache_pte_range(struct mm_struct *mm, pmd_t *pmd, unsigned long address, unsigned long size)
{
	unsigned long offset;
	pte_t *ptep;

	if (pmd_none(*pmd))
		return;
	ptep = pte_offset_map(pmd, address);
	offset = address & ~PMD_MASK;
	if (offset + size > PMD_SIZE)
		size = PMD_SIZE - offset;
	size &= PAGE_MASK;
	for (offset = 0; offset < size; ptep++, offset += PAGE_SIZE) {
		pte_t pte = *ptep;

		if (pte_none(pte))
			continue;

		if (pte_present(pte) && pte_dirty(pte)) {
			struct page *page = pte_page(pte);
			unsigned long pgaddr, uaddr;

			if (!VALID_PAGE(page) || PageReserved(page) || !page->mapping)
				continue;
			pgaddr = (unsigned long) page_address(page);
			uaddr = address + offset;
			if ((pgaddr ^ uaddr) & (1 << 13))
				flush_dcache_page_all(mm, page);
		}
	}
	pte_unmap(ptep - 1);
}

static inline void flush_cache_pmd_range(struct mm_struct *mm, pgd_t *dir, unsigned long address, unsigned long size)
{
	pmd_t *pmd;
	unsigned long end;

	if (pgd_none(*dir))
		return;
	pmd = pmd_offset(dir, address);
	end = address + size;
	if (end > ((address + PGDIR_SIZE) & PGDIR_MASK))
		end = ((address + PGDIR_SIZE) & PGDIR_MASK);
	do {
		flush_cache_pte_range(mm, pmd, address, end - address);
		address = (address + PMD_SIZE) & PMD_MASK;
		pmd++;
	} while (address < end);
}

void flush_cache_range(struct vm_area_struct *vma, unsigned long start, unsigned long end)
{
	struct mm_struct *mm = vma->vm_mm;
	pgd_t *dir = pgd_offset(mm, start);

	if (mm == current->mm)
		flushw_user();

	if (vma->vm_file == NULL ||
	    ((vma->vm_flags & (VM_SHARED|VM_WRITE)) != (VM_SHARED|VM_WRITE)))
		return;

	do {
		flush_cache_pmd_range(mm, dir, start, end - start);
		start = (start + PGDIR_SIZE) & PGDIR_MASK;
		dir++;
	} while (start && (start < end));
}

void flush_icache_range(unsigned long start, unsigned long end)
{
	/* Cheetah has coherent I-cache. */
	if (tlb_type == spitfire) {
		unsigned long kaddr;

		for (kaddr = start; kaddr < end; kaddr += PAGE_SIZE)
			__flush_icache_page(__get_phys(kaddr));
	}
}

void show_mem(void)
{
	printk("Mem-info:\n");
	show_free_areas();
	printk("Free swap:       %6dkB\n",
	       nr_swap_pages << (PAGE_SHIFT-10));
	printk("%ld pages of RAM\n", num_physpages);
	printk("%d free pages\n", nr_free_pages());
	printk("%d pages in page table cache\n",pgtable_cache_size);
#ifndef CONFIG_SMP
	printk("%d entries in page dir cache\n",pgd_cache_size);
#endif	
	printk("%ld buffermem pages\n", nr_buffermem_pages());
}

void mmu_info(struct seq_file *m)
{
	if (tlb_type == cheetah)
		seq_printf(m, "MMU Type\t: Cheetah\n");
	else if (tlb_type == spitfire)
		seq_printf(m, "MMU Type\t: Spitfire\n");
	else
		seq_printf(m, "MMU Type\t: ???\n");

#ifdef CONFIG_DEBUG_DCFLUSH
	seq_printf(m, "DCPageFlushes\t: %d\n",
		   atomic_read(&dcpage_flushes));
#ifdef CONFIG_SMP
	seq_printf(m, "DCPageFlushesXC\t: %d\n",
		   atomic_read(&dcpage_flushes_xcall));
#endif /* CONFIG_SMP */
#endif /* CONFIG_DEBUG_DCFLUSH */
}

struct linux_prom_translation {
	unsigned long virt;
	unsigned long size;
	unsigned long data;
};

extern unsigned long prom_boot_page;
extern void prom_remap(unsigned long physpage, unsigned long virtpage, int mmu_ihandle);
extern int prom_get_mmu_ihandle(void);
extern void register_prom_callbacks(void);

/* Exported for SMP bootup purposes. */
unsigned long kern_locked_tte_data;

void __init early_pgtable_allocfail(char *type)
{
	prom_printf("inherit_prom_mappings: Cannot alloc kernel %s.\n", type);
	prom_halt();
}

#define BASE_PAGE_SIZE 8192
static pmd_t *prompmd;

/*
 * Translate PROM's mapping we capture at boot time into physical address.
 * The second parameter is only set from prom_callback() invocations.
 */
unsigned long prom_virt_to_phys(unsigned long promva, int *error)
{
	pmd_t *pmdp = prompmd + ((promva >> 23) & 0x7ff);
	pte_t *ptep;
	unsigned long base;

	if (pmd_none(*pmdp)) {
		if (error)
			*error = 1;
		return(0);
	}
	ptep = (pte_t *)__pmd_page(*pmdp) + ((promva >> 13) & 0x3ff);
	if (!pte_present(*ptep)) {
		if (error)
			*error = 1;
		return(0);
	}
	if (error) {
		*error = 0;
		return(pte_val(*ptep));
	}
	base = pte_val(*ptep) & _PAGE_PADDR;
	return(base + (promva & (BASE_PAGE_SIZE - 1)));
}

static void inherit_prom_mappings(void)
{
	struct linux_prom_translation *trans;
	unsigned long phys_page, tte_vaddr, tte_data;
	void (*remap_func)(unsigned long, unsigned long, int);
	pmd_t *pmdp;
	pte_t *ptep;
	int node, n, i, tsz;
	extern unsigned int obp_iaddr_patch[2], obp_daddr_patch[2];

	node = prom_finddevice("/virtual-memory");
	n = prom_getproplen(node, "translations");
	if (n == 0 || n == -1) {
		prom_printf("Couldn't get translation property\n");
		prom_halt();
	}
	n += 5 * sizeof(struct linux_prom_translation);
	for (tsz = 1; tsz < n; tsz <<= 1)
		/* empty */;
	trans = __alloc_bootmem(tsz, SMP_CACHE_BYTES, 0UL);
	if (trans == NULL) {
		prom_printf("inherit_prom_mappings: Cannot alloc translations.\n");
		prom_halt();
	}
	memset(trans, 0, tsz);

	if ((n = prom_getproperty(node, "translations", (char *)trans, tsz)) == -1) {
		prom_printf("Couldn't get translation property\n");
		prom_halt();
	}
	n = n / sizeof(*trans);

	/*
	 * The obp translations are saved based on 8k pagesize, since obp can use
	 * a mixture of pagesizes. Misses to the 0xf0000000 - 0x100000000, ie obp 
	 * range, are handled in entry.S and do not use the vpte scheme (see rant
	 * in inherit_locked_prom_mappings()).
	 */
#define OBP_PMD_SIZE 2048
	prompmd = __alloc_bootmem(OBP_PMD_SIZE, OBP_PMD_SIZE, 0UL);
	if (prompmd == NULL)
		early_pgtable_allocfail("pmd");
	memset(prompmd, 0, OBP_PMD_SIZE);
	for (i = 0; i < n; i++) {
		unsigned long vaddr;

		if (trans[i].virt >= LOW_OBP_ADDRESS && trans[i].virt < HI_OBP_ADDRESS) {
			for (vaddr = trans[i].virt;
			     ((vaddr < trans[i].virt + trans[i].size) && 
			     (vaddr < HI_OBP_ADDRESS));
			     vaddr += BASE_PAGE_SIZE) {
				unsigned long val;

				pmdp = prompmd + ((vaddr >> 23) & 0x7ff);
				if (pmd_none(*pmdp)) {
					ptep = __alloc_bootmem(BASE_PAGE_SIZE,
							       BASE_PAGE_SIZE,
							       0UL);
					if (ptep == NULL)
						early_pgtable_allocfail("pte");
					memset(ptep, 0, BASE_PAGE_SIZE);
					pmd_set(pmdp, ptep);
				}
				ptep = (pte_t *)__pmd_page(*pmdp) +
						((vaddr >> 13) & 0x3ff);

				val = trans[i].data;

				/* Clear diag TTE bits. */
				if (tlb_type == spitfire)
					val &= ~0x0003fe0000000000UL;

				set_pte (ptep, __pte(val | _PAGE_MODIFIED));
				trans[i].data += BASE_PAGE_SIZE;
			}
		}
	}
	phys_page = __pa(prompmd);
	obp_iaddr_patch[0] |= (phys_page >> 10);
	obp_iaddr_patch[1] |= (phys_page & 0x3ff);
	flushi((long)&obp_iaddr_patch[0]);
	obp_daddr_patch[0] |= (phys_page >> 10);
	obp_daddr_patch[1] |= (phys_page & 0x3ff);
	flushi((long)&obp_daddr_patch[0]);

	/* Now fixup OBP's idea about where we really are mapped. */
	prom_printf("Remapping the kernel... ");

	/* Spitfire Errata #32 workaround */
	__asm__ __volatile__("stxa	%0, [%1] %2\n\t"
			     "flush	%%g6"
			     : /* No outputs */
			     : "r" (0),
			     "r" (PRIMARY_CONTEXT), "i" (ASI_DMMU));

	switch (tlb_type) {
	default:
	case spitfire:
		phys_page = spitfire_get_dtlb_data(sparc64_highest_locked_tlbent());
		break;

	case cheetah:
		phys_page = cheetah_get_litlb_data(sparc64_highest_locked_tlbent());
		break;
	};

	phys_page &= _PAGE_PADDR;
	phys_page += ((unsigned long)&prom_boot_page -
		      (unsigned long)KERNBASE);

	if (tlb_type == spitfire) {
		/* Lock this into i/d tlb entry 59 */
		__asm__ __volatile__(
			"stxa	%%g0, [%2] %3\n\t"
			"stxa	%0, [%1] %4\n\t"
			"membar	#Sync\n\t"
			"flush	%%g6\n\t"
			"stxa	%%g0, [%2] %5\n\t"
			"stxa	%0, [%1] %6\n\t"
			"membar	#Sync\n\t"
			"flush	%%g6"
			: : "r" (phys_page | _PAGE_VALID | _PAGE_SZ8K | _PAGE_CP |
				 _PAGE_CV | _PAGE_P | _PAGE_L | _PAGE_W),
			"r" (59 << 3), "r" (TLB_TAG_ACCESS),
			"i" (ASI_DMMU), "i" (ASI_DTLB_DATA_ACCESS),
			"i" (ASI_IMMU), "i" (ASI_ITLB_DATA_ACCESS)
			: "memory");
	} else if (tlb_type == cheetah) {
		/* Lock this into i/d tlb-0 entry 11 */
		__asm__ __volatile__(
			"stxa	%%g0, [%2] %3\n\t"
			"stxa	%0, [%1] %4\n\t"
			"membar	#Sync\n\t"
			"flush	%%g6\n\t"
			"stxa	%%g0, [%2] %5\n\t"
			"stxa	%0, [%1] %6\n\t"
			"membar	#Sync\n\t"
			"flush	%%g6"
			: : "r" (phys_page | _PAGE_VALID | _PAGE_SZ8K | _PAGE_CP |
				 _PAGE_CV | _PAGE_P | _PAGE_L | _PAGE_W),
			"r" ((0 << 16) | (11 << 3)), "r" (TLB_TAG_ACCESS),
			"i" (ASI_DMMU), "i" (ASI_DTLB_DATA_ACCESS),
			"i" (ASI_IMMU), "i" (ASI_ITLB_DATA_ACCESS)
			: "memory");
	} else {
		/* Implement me :-) */
		BUG();
	}

	tte_vaddr = (unsigned long) KERNBASE;

	/* Spitfire Errata #32 workaround */
	__asm__ __volatile__("stxa	%0, [%1] %2\n\t"
			     "flush	%%g6"
			     : /* No outputs */
			     : "r" (0),
			     "r" (PRIMARY_CONTEXT), "i" (ASI_DMMU));

	if (tlb_type == spitfire)
		tte_data = spitfire_get_dtlb_data(sparc64_highest_locked_tlbent());
	else
		tte_data = cheetah_get_ldtlb_data(sparc64_highest_locked_tlbent());

	kern_locked_tte_data = tte_data;

	remap_func = (void *)  ((unsigned long) &prom_remap -
				(unsigned long) &prom_boot_page);


	/* Spitfire Errata #32 workaround */
	__asm__ __volatile__("stxa	%0, [%1] %2\n\t"
			     "flush	%%g6"
			     : /* No outputs */
			     : "r" (0),
			     "r" (PRIMARY_CONTEXT), "i" (ASI_DMMU));

	remap_func((tlb_type == spitfire ?
		    (spitfire_get_dtlb_data(sparc64_highest_locked_tlbent()) & _PAGE_PADDR) :
		    (cheetah_get_litlb_data(sparc64_highest_locked_tlbent()) & _PAGE_PADDR)),
		   (unsigned long) KERNBASE,
		   prom_get_mmu_ihandle());

	if (bigkernel)
		remap_func(((tte_data + 0x400000) & _PAGE_PADDR),
			(unsigned long) KERNBASE + 0x400000, prom_get_mmu_ihandle());

	/* Flush out that temporary mapping. */
	spitfire_flush_dtlb_nucleus_page(0x0);
	spitfire_flush_itlb_nucleus_page(0x0);

	/* Now lock us back into the TLBs via OBP. */
	prom_dtlb_load(sparc64_highest_locked_tlbent(), tte_data, tte_vaddr);
	prom_itlb_load(sparc64_highest_locked_tlbent(), tte_data, tte_vaddr);
	if (bigkernel) {
		prom_dtlb_load(sparc64_highest_locked_tlbent()-1, tte_data + 0x400000, 
								tte_vaddr + 0x400000);
		prom_itlb_load(sparc64_highest_locked_tlbent()-1, tte_data + 0x400000, 
								tte_vaddr + 0x400000);
	}

	/* Re-read translations property. */
	if ((n = prom_getproperty(node, "translations", (char *)trans, tsz)) == -1) {
		prom_printf("Couldn't get translation property\n");
		prom_halt();
	}
	n = n / sizeof(*trans);

	for (i = 0; i < n; i++) {
		unsigned long vaddr = trans[i].virt;
		unsigned long size = trans[i].size;

		if (vaddr < 0xf0000000UL) {
			unsigned long avoid_start = (unsigned long) KERNBASE;
			unsigned long avoid_end = avoid_start + (4 * 1024 * 1024);

			if (bigkernel)
				avoid_end += (4 * 1024 * 1024);
			if (vaddr < avoid_start) {
				unsigned long top = vaddr + size;

				if (top > avoid_start)
					top = avoid_start;
				prom_unmap(top - vaddr, vaddr);
			}
			if ((vaddr + size) > avoid_end) {
				unsigned long bottom = vaddr;

				if (bottom < avoid_end)
					bottom = avoid_end;
				prom_unmap((vaddr + size) - bottom, bottom);
			}
		}
	}

	prom_printf("done.\n");

	register_prom_callbacks();
}

/* The OBP specifications for sun4u mark 0xfffffffc00000000 and
 * upwards as reserved for use by the firmware (I wonder if this
 * will be the same on Cheetah...).  We use this virtual address
 * range for the VPTE table mappings of the nucleus so we need
 * to zap them when we enter the PROM.  -DaveM
 */
static void __flush_nucleus_vptes(void)
{
	unsigned long prom_reserved_base = 0xfffffffc00000000UL;
	int i;

	/* Only DTLB must be checked for VPTE entries. */
	if (tlb_type == spitfire) {
		for (i = 0; i < 63; i++) {
			unsigned long tag;

			/* Spitfire Errata #32 workaround */
			__asm__ __volatile__("stxa	%0, [%1] %2\n\t"
					     "flush	%%g6"
					     : /* No outputs */
					     : "r" (0),
					     "r" (PRIMARY_CONTEXT), "i" (ASI_DMMU));

			tag = spitfire_get_dtlb_tag(i);
			if (((tag & ~(PAGE_MASK)) == 0) &&
			    ((tag &  (PAGE_MASK)) >= prom_reserved_base)) {
				__asm__ __volatile__("stxa %%g0, [%0] %1\n\t"
						     "membar #Sync"
						     : /* no outputs */
						     : "r" (TLB_TAG_ACCESS), "i" (ASI_DMMU));
				spitfire_put_dtlb_data(i, 0x0UL);
			}
		}
	} else if (tlb_type == cheetah) {
		for (i = 0; i < 512; i++) {
			unsigned long tag = cheetah_get_dtlb_tag(i);

			if ((tag & ~PAGE_MASK) == 0 &&
			    (tag & PAGE_MASK) >= prom_reserved_base) {
				__asm__ __volatile__("stxa %%g0, [%0] %1\n\t"
						     "membar #Sync"
						     : /* no outputs */
						     : "r" (TLB_TAG_ACCESS), "i" (ASI_DMMU));
				cheetah_put_dtlb_data(i, 0x0UL);
			}
		}
	} else {
		/* Implement me :-) */
		BUG();
	}
}

static int prom_ditlb_set;
struct prom_tlb_entry {
	int		tlb_ent;
	unsigned long	tlb_tag;
	unsigned long	tlb_data;
};
struct prom_tlb_entry prom_itlb[16], prom_dtlb[16];

void prom_world(int enter)
{
	unsigned long pstate;
	int i;

	if (!enter)
		set_fs((mm_segment_t) { get_thread_current_ds() });

	if (!prom_ditlb_set)
		return;

	/* Make sure the following runs atomically. */
	__asm__ __volatile__("flushw\n\t"
			     "rdpr	%%pstate, %0\n\t"
			     "wrpr	%0, %1, %%pstate"
			     : "=r" (pstate)
			     : "i" (PSTATE_IE));

	if (enter) {
		/* Kick out nucleus VPTEs. */
		__flush_nucleus_vptes();

		/* Install PROM world. */
		for (i = 0; i < 16; i++) {
			if (prom_dtlb[i].tlb_ent != -1) {
				__asm__ __volatile__("stxa %0, [%1] %2\n\t"
						     "membar #Sync"
					: : "r" (prom_dtlb[i].tlb_tag), "r" (TLB_TAG_ACCESS),
					"i" (ASI_DMMU));
				if (tlb_type == spitfire)
					spitfire_put_dtlb_data(prom_dtlb[i].tlb_ent,
							       prom_dtlb[i].tlb_data);
				else if (tlb_type == cheetah)
					cheetah_put_ldtlb_data(prom_dtlb[i].tlb_ent,
							       prom_dtlb[i].tlb_data);
			}
			if (prom_itlb[i].tlb_ent != -1) {
				__asm__ __volatile__("stxa %0, [%1] %2\n\t"
						     "membar #Sync"
						     : : "r" (prom_itlb[i].tlb_tag),
						     "r" (TLB_TAG_ACCESS),
						     "i" (ASI_IMMU));
				if (tlb_type == spitfire)
					spitfire_put_itlb_data(prom_itlb[i].tlb_ent,
							       prom_itlb[i].tlb_data);
				else if (tlb_type == cheetah)
					cheetah_put_litlb_data(prom_itlb[i].tlb_ent,
							       prom_itlb[i].tlb_data);
			}
		}
	} else {
		for (i = 0; i < 16; i++) {
			if (prom_dtlb[i].tlb_ent != -1) {
				__asm__ __volatile__("stxa %%g0, [%0] %1\n\t"
						     "membar #Sync"
					: : "r" (TLB_TAG_ACCESS), "i" (ASI_DMMU));
				if (tlb_type == spitfire)
					spitfire_put_dtlb_data(prom_dtlb[i].tlb_ent, 0x0UL);
				else
					cheetah_put_ldtlb_data(prom_dtlb[i].tlb_ent, 0x0UL);
			}
			if (prom_itlb[i].tlb_ent != -1) {
				__asm__ __volatile__("stxa %%g0, [%0] %1\n\t"
						     "membar #Sync"
						     : : "r" (TLB_TAG_ACCESS),
						     "i" (ASI_IMMU));
				if (tlb_type == spitfire)
					spitfire_put_itlb_data(prom_itlb[i].tlb_ent, 0x0UL);
				else
					cheetah_put_litlb_data(prom_itlb[i].tlb_ent, 0x0UL);
			}
		}
	}
	__asm__ __volatile__("wrpr	%0, 0, %%pstate"
			     : : "r" (pstate));
}

void inherit_locked_prom_mappings(int save_p)
{
	int i;
	int dtlb_seen = 0;
	int itlb_seen = 0;

	/* Fucking losing PROM has more mappings in the TLB, but
	 * it (conveniently) fails to mention any of these in the
	 * translations property.  The only ones that matter are
	 * the locked PROM tlb entries, so we impose the following
	 * irrecovable rule on the PROM, it is allowed 8 locked
	 * entries in the ITLB and 8 in the DTLB.
	 *
	 * Supposedly the upper 16GB of the address space is
	 * reserved for OBP, BUT I WISH THIS WAS DOCUMENTED
	 * SOMEWHERE!!!!!!!!!!!!!!!!!  Furthermore the entire interface
	 * used between the client program and the firmware on sun5
	 * systems to coordinate mmu mappings is also COMPLETELY
	 * UNDOCUMENTED!!!!!! Thanks S(t)un!
	 */
	if (save_p) {
		for (i = 0; i < 16; i++) {
			prom_itlb[i].tlb_ent = -1;
			prom_dtlb[i].tlb_ent = -1;
		}
	}
	if (tlb_type == spitfire) {
		int high = SPITFIRE_HIGHEST_LOCKED_TLBENT - bigkernel;
		for (i = 0; i < high; i++) {
			unsigned long data;

			/* Spitfire Errata #32 workaround */
			__asm__ __volatile__("stxa	%0, [%1] %2\n\t"
					     "flush	%%g6"
					     : /* No outputs */
					     : "r" (0),
					     "r" (PRIMARY_CONTEXT), "i" (ASI_DMMU));

			data = spitfire_get_dtlb_data(i);
			if ((data & (_PAGE_L|_PAGE_VALID)) == (_PAGE_L|_PAGE_VALID)) {
				unsigned long tag;

				/* Spitfire Errata #32 workaround */
				__asm__ __volatile__("stxa	%0, [%1] %2\n\t"
						     "flush	%%g6"
						     : /* No outputs */
						     : "r" (0),
						     "r" (PRIMARY_CONTEXT), "i" (ASI_DMMU));

				tag = spitfire_get_dtlb_tag(i);
				if (save_p) {
					prom_dtlb[dtlb_seen].tlb_ent = i;
					prom_dtlb[dtlb_seen].tlb_tag = tag;
					prom_dtlb[dtlb_seen].tlb_data = data;
				}
				__asm__ __volatile__("stxa %%g0, [%0] %1\n\t"
						     "membar #Sync"
						     : : "r" (TLB_TAG_ACCESS), "i" (ASI_DMMU));
				spitfire_put_dtlb_data(i, 0x0UL);

				dtlb_seen++;
				if (dtlb_seen > 15)
					break;
			}
		}

		for (i = 0; i < high; i++) {
			unsigned long data;

			/* Spitfire Errata #32 workaround */
			__asm__ __volatile__("stxa	%0, [%1] %2\n\t"
					     "flush	%%g6"
					     : /* No outputs */
					     : "r" (0),
					     "r" (PRIMARY_CONTEXT), "i" (ASI_DMMU));

			data = spitfire_get_itlb_data(i);
			if ((data & (_PAGE_L|_PAGE_VALID)) == (_PAGE_L|_PAGE_VALID)) {
				unsigned long tag;

				/* Spitfire Errata #32 workaround */
				__asm__ __volatile__("stxa	%0, [%1] %2\n\t"
						     "flush	%%g6"
						     : /* No outputs */
						     : "r" (0),
						     "r" (PRIMARY_CONTEXT), "i" (ASI_DMMU));

				tag = spitfire_get_itlb_tag(i);
				if (save_p) {
					prom_itlb[itlb_seen].tlb_ent = i;
					prom_itlb[itlb_seen].tlb_tag = tag;
					prom_itlb[itlb_seen].tlb_data = data;
				}
				__asm__ __volatile__("stxa %%g0, [%0] %1\n\t"
						     "membar #Sync"
						     : : "r" (TLB_TAG_ACCESS), "i" (ASI_IMMU));
				spitfire_put_itlb_data(i, 0x0UL);

				itlb_seen++;
				if (itlb_seen > 15)
					break;
			}
		}
	} else if (tlb_type == cheetah) {
		int high = CHEETAH_HIGHEST_LOCKED_TLBENT - bigkernel;

		for (i = 0; i < high; i++) {
			unsigned long data;

			data = cheetah_get_ldtlb_data(i);
			if ((data & (_PAGE_L|_PAGE_VALID)) == (_PAGE_L|_PAGE_VALID)) {
				unsigned long tag;

				tag = cheetah_get_ldtlb_tag(i);
				if (save_p) {
					prom_dtlb[dtlb_seen].tlb_ent = i;
					prom_dtlb[dtlb_seen].tlb_tag = tag;
					prom_dtlb[dtlb_seen].tlb_data = data;
				}
				__asm__ __volatile__("stxa %%g0, [%0] %1\n\t"
						     "membar #Sync"
						     : : "r" (TLB_TAG_ACCESS), "i" (ASI_DMMU));
				cheetah_put_ldtlb_data(i, 0x0UL);

				dtlb_seen++;
				if (dtlb_seen > 15)
					break;
			}
		}

		for (i = 0; i < high; i++) {
			unsigned long data;

			data = cheetah_get_litlb_data(i);
			if ((data & (_PAGE_L|_PAGE_VALID)) == (_PAGE_L|_PAGE_VALID)) {
				unsigned long tag;

				tag = cheetah_get_litlb_tag(i);
				if (save_p) {
					prom_itlb[itlb_seen].tlb_ent = i;
					prom_itlb[itlb_seen].tlb_tag = tag;
					prom_itlb[itlb_seen].tlb_data = data;
				}
				__asm__ __volatile__("stxa %%g0, [%0] %1\n\t"
						     "membar #Sync"
						     : : "r" (TLB_TAG_ACCESS), "i" (ASI_IMMU));
				cheetah_put_litlb_data(i, 0x0UL);

				itlb_seen++;
				if (itlb_seen > 15)
					break;
			}
		}
	} else {
		/* Implement me :-) */
		BUG();
	}
	if (save_p)
		prom_ditlb_set = 1;
}

/* Give PROM back his world, done during reboots... */
void prom_reload_locked(void)
{
	int i;

	for (i = 0; i < 16; i++) {
		if (prom_dtlb[i].tlb_ent != -1) {
			__asm__ __volatile__("stxa %0, [%1] %2\n\t"
					     "membar #Sync"
				: : "r" (prom_dtlb[i].tlb_tag), "r" (TLB_TAG_ACCESS),
				"i" (ASI_DMMU));
			if (tlb_type == spitfire)
				spitfire_put_dtlb_data(prom_dtlb[i].tlb_ent,
						       prom_dtlb[i].tlb_data);
			else if (tlb_type == cheetah)
				cheetah_put_ldtlb_data(prom_dtlb[i].tlb_ent,
						      prom_dtlb[i].tlb_data);
		}

		if (prom_itlb[i].tlb_ent != -1) {
			__asm__ __volatile__("stxa %0, [%1] %2\n\t"
					     "membar #Sync"
					     : : "r" (prom_itlb[i].tlb_tag),
					     "r" (TLB_TAG_ACCESS),
					     "i" (ASI_IMMU));
			if (tlb_type == spitfire)
				spitfire_put_itlb_data(prom_itlb[i].tlb_ent,
						       prom_itlb[i].tlb_data);
			else
				cheetah_put_litlb_data(prom_itlb[i].tlb_ent,
						       prom_itlb[i].tlb_data);
		}
	}
}

void __flush_dcache_range(unsigned long start, unsigned long end)
{
	unsigned long va;

	if (tlb_type == spitfire) {
		int n = 0;

		for (va = start; va < end; va += 32) {
			spitfire_put_dcache_tag(va & 0x3fe0, 0x0);
			if (++n >= 512)
				break;
		}
	} else {
		start = __pa(start);
		end = __pa(end);
		for (va = start; va < end; va += 32)
			__asm__ __volatile__("stxa %%g0, [%0] %1\n\t"
					     "membar #Sync"
					     : /* no outputs */
					     : "r" (va),
					       "i" (ASI_DCACHE_INVALIDATE));
	}
}

void __flush_cache_all(void)
{
	/* Cheetah should be fine here too. */
	if (tlb_type == spitfire) {
		unsigned long va;

		flushw_all();
		for (va =  0; va < (PAGE_SIZE << 1); va += 32)
			spitfire_put_icache_tag(va, 0x0);
		__asm__ __volatile__("flush %g6");
	}
}

/* If not locked, zap it. */
void __flush_tlb_all(void)
{
	unsigned long pstate;
	int i;

	__asm__ __volatile__("flushw\n\t"
			     "rdpr	%%pstate, %0\n\t"
			     "wrpr	%0, %1, %%pstate"
			     : "=r" (pstate)
			     : "i" (PSTATE_IE));
	if (tlb_type == spitfire) {
		for (i = 0; i < 64; i++) {
			/* Spitfire Errata #32 workaround */
			__asm__ __volatile__("stxa	%0, [%1] %2\n\t"
					     "flush	%%g6"
					     : /* No outputs */
					     : "r" (0),
					     "r" (PRIMARY_CONTEXT), "i" (ASI_DMMU));

			if (!(spitfire_get_dtlb_data(i) & _PAGE_L)) {
				__asm__ __volatile__("stxa %%g0, [%0] %1\n\t"
						     "membar #Sync"
						     : /* no outputs */
						     : "r" (TLB_TAG_ACCESS), "i" (ASI_DMMU));
				spitfire_put_dtlb_data(i, 0x0UL);
			}

			/* Spitfire Errata #32 workaround */
			__asm__ __volatile__("stxa	%0, [%1] %2\n\t"
					     "flush	%%g6"
					     : /* No outputs */
					     : "r" (0),
					     "r" (PRIMARY_CONTEXT), "i" (ASI_DMMU));

			if (!(spitfire_get_itlb_data(i) & _PAGE_L)) {
				__asm__ __volatile__("stxa %%g0, [%0] %1\n\t"
						     "membar #Sync"
						     : /* no outputs */
						     : "r" (TLB_TAG_ACCESS), "i" (ASI_IMMU));
				spitfire_put_itlb_data(i, 0x0UL);
			}
		}
	} else if (tlb_type == cheetah) {
		cheetah_flush_dtlb_all();
		cheetah_flush_itlb_all();
	}
	__asm__ __volatile__("wrpr	%0, 0, %%pstate"
			     : : "r" (pstate));
}

/* Caller does TLB context flushing on local CPU if necessary.
 * The caller also ensures that CTX_VALID(mm->context) is false.
 *
 * We must be careful about boundary cases so that we never
 * let the user have CTX 0 (nucleus) or we ever use a CTX
 * version of zero (and thus NO_CONTEXT would not be caught
 * by version mis-match tests in mmu_context.h).
 */
void get_new_mmu_context(struct mm_struct *mm)
{
	unsigned long ctx, new_ctx;
	
	spin_lock(&ctx_alloc_lock);
	ctx = CTX_HWBITS(tlb_context_cache + 1);
	new_ctx = find_next_zero_bit(mmu_context_bmap, 1UL << CTX_VERSION_SHIFT, ctx);
	if (new_ctx >= (1UL << CTX_VERSION_SHIFT)) {
		new_ctx = find_next_zero_bit(mmu_context_bmap, ctx, 1);
		if (new_ctx >= ctx) {
			int i;
			new_ctx = (tlb_context_cache & CTX_VERSION_MASK) +
				CTX_FIRST_VERSION;
			if (new_ctx == 1)
				new_ctx = CTX_FIRST_VERSION;

			/* Don't call memset, for 16 entries that's just
			 * plain silly...
			 */
			mmu_context_bmap[0] = 3;
			mmu_context_bmap[1] = 0;
			mmu_context_bmap[2] = 0;
			mmu_context_bmap[3] = 0;
			for (i = 4; i < CTX_BMAP_SLOTS; i += 4) {
				mmu_context_bmap[i + 0] = 0;
				mmu_context_bmap[i + 1] = 0;
				mmu_context_bmap[i + 2] = 0;
				mmu_context_bmap[i + 3] = 0;
			}
			goto out;
		}
	}
	mmu_context_bmap[new_ctx>>6] |= (1UL << (new_ctx & 63));
	new_ctx |= (tlb_context_cache & CTX_VERSION_MASK);
out:
	tlb_context_cache = new_ctx;
	spin_unlock(&ctx_alloc_lock);

	mm->context = new_ctx;
}

#ifndef CONFIG_SMP
struct pgtable_cache_struct pgt_quicklists;
#endif

/* OK, we have to color these pages. The page tables are accessed
 * by non-Dcache enabled mapping in the VPTE area by the dtlb_backend.S
 * code, as well as by PAGE_OFFSET range direct-mapped addresses by 
 * other parts of the kernel. By coloring, we make sure that the tlbmiss 
 * fast handlers do not get data from old/garbage dcache lines that 
 * correspond to an old/stale virtual address (user/kernel) that 
 * previously mapped the pagetable page while accessing vpte range 
 * addresses. The idea is that if the vpte color and PAGE_OFFSET range 
 * color is the same, then when the kernel initializes the pagetable 
 * using the later address range, accesses with the first address
 * range will see the newly initialized data rather than the garbage.
 */
#if (L1DCACHE_SIZE > PAGE_SIZE)			/* is there D$ aliasing problem */
#define DC_ALIAS_SHIFT	1
#else
#define DC_ALIAS_SHIFT	0
#endif
pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
{
	struct page *page;
	unsigned long color;

	{
		pte_t *ptep = pte_alloc_one_fast(mm, address);

		if (ptep)
			return ptep;
	}

	color = VPTE_COLOR(address);
	page = alloc_pages(GFP_KERNEL, DC_ALIAS_SHIFT);
	if (page) {
		unsigned long *to_free;
		unsigned long paddr;
		pte_t *pte;

#if (L1DCACHE_SIZE > PAGE_SIZE)			/* is there D$ aliasing problem */
		set_page_count((page + 1), 1);
#endif
		paddr = (unsigned long) page_address(page);
		memset((char *)paddr, 0, (PAGE_SIZE << DC_ALIAS_SHIFT));

		if (!color) {
			pte = (pte_t *) paddr;
			to_free = (unsigned long *) (paddr + PAGE_SIZE);
		} else {
			pte = (pte_t *) (paddr + PAGE_SIZE);
			to_free = (unsigned long *) paddr;
		}

#if (L1DCACHE_SIZE > PAGE_SIZE)			/* is there D$ aliasing problem */
		/* Now free the other one up, adjust cache size. */
		preempt_disable();
		*to_free = (unsigned long) pte_quicklist[color ^ 0x1];
		pte_quicklist[color ^ 0x1] = to_free;
		pgtable_cache_size++;
		preempt_enable();
#endif

		return pte;
	}
	return NULL;
}

void sparc_ultra_dump_itlb(void)
{
        int slot;

	if (tlb_type == spitfire) {
		printk ("Contents of itlb: ");
		for (slot = 0; slot < 14; slot++) printk ("    ");
		printk ("%2x:%016lx,%016lx\n",
			0,
			spitfire_get_itlb_tag(0), spitfire_get_itlb_data(0));
		for (slot = 1; slot < 64; slot+=3) {
			printk ("%2x:%016lx,%016lx %2x:%016lx,%016lx %2x:%016lx,%016lx\n", 
				slot,
				spitfire_get_itlb_tag(slot), spitfire_get_itlb_data(slot),
				slot+1,
				spitfire_get_itlb_tag(slot+1), spitfire_get_itlb_data(slot+1),
				slot+2,
				spitfire_get_itlb_tag(slot+2), spitfire_get_itlb_data(slot+2));
		}
	} else if (tlb_type == cheetah) {
		printk ("Contents of itlb0:\n");
		for (slot = 0; slot < 16; slot+=2) {
			printk ("%2x:%016lx,%016lx %2x:%016lx,%016lx\n",
				slot,
				cheetah_get_litlb_tag(slot), cheetah_get_litlb_data(slot),
				slot+1,
				cheetah_get_litlb_tag(slot+1), cheetah_get_litlb_data(slot+1));
		}
		printk ("Contents of itlb2:\n");
		for (slot = 0; slot < 128; slot+=2) {
			printk ("%2x:%016lx,%016lx %2x:%016lx,%016lx\n",
				slot,
				cheetah_get_itlb_tag(slot), cheetah_get_itlb_data(slot),
				slot+1,
				cheetah_get_itlb_tag(slot+1), cheetah_get_itlb_data(slot+1));
		}
	}
}

void sparc_ultra_dump_dtlb(void)
{
        int slot;

	if (tlb_type == spitfire) {
		printk ("Contents of dtlb: ");
		for (slot = 0; slot < 14; slot++) printk ("    ");
		printk ("%2x:%016lx,%016lx\n", 0,
			spitfire_get_dtlb_tag(0), spitfire_get_dtlb_data(0));
		for (slot = 1; slot < 64; slot+=3) {
			printk ("%2x:%016lx,%016lx %2x:%016lx,%016lx %2x:%016lx,%016lx\n", 
				slot,
				spitfire_get_dtlb_tag(slot), spitfire_get_dtlb_data(slot),
				slot+1,
				spitfire_get_dtlb_tag(slot+1), spitfire_get_dtlb_data(slot+1),
				slot+2,
				spitfire_get_dtlb_tag(slot+2), spitfire_get_dtlb_data(slot+2));
		}
	} else if (tlb_type == cheetah) {
		printk ("Contents of dtlb0:\n");
		for (slot = 0; slot < 16; slot+=2) {
			printk ("%2x:%016lx,%016lx %2x:%016lx,%016lx\n",
				slot,
				cheetah_get_ldtlb_tag(slot), cheetah_get_ldtlb_data(slot),
				slot+1,
				cheetah_get_ldtlb_tag(slot+1), cheetah_get_ldtlb_data(slot+1));
		}
		printk ("Contents of dtlb2:\n");
		for (slot = 0; slot < 512; slot+=2) {
			printk ("%2x:%016lx,%016lx %2x:%016lx,%016lx\n",
				slot,
				cheetah_get_dtlb_tag(slot), cheetah_get_dtlb_data(slot),
				slot+1,
				cheetah_get_dtlb_tag(slot+1), cheetah_get_dtlb_data(slot+1));
		}
	}
}

extern unsigned long cmdline_memory_size;

unsigned long __init bootmem_init(unsigned long *pages_avail)
{
	unsigned long bootmap_size, start_pfn, end_pfn;
	unsigned long end_of_phys_memory = 0UL;
	unsigned long bootmap_pfn, bytes_avail, size;
	int i;

	bytes_avail = 0UL;
	for (i = 0; sp_banks[i].num_bytes != 0; i++) {
		end_of_phys_memory = sp_banks[i].base_addr +
			sp_banks[i].num_bytes;
		bytes_avail += sp_banks[i].num_bytes;
		if (cmdline_memory_size) {
			if (bytes_avail > cmdline_memory_size) {
				unsigned long slack = bytes_avail - cmdline_memory_size;

				bytes_avail -= slack;
				end_of_phys_memory -= slack;

				sp_banks[i].num_bytes -= slack;
				if (sp_banks[i].num_bytes == 0) {
					sp_banks[i].base_addr = 0xdeadbeef;
				} else {
					sp_banks[i+1].num_bytes = 0;
					sp_banks[i+1].base_addr = 0xdeadbeef;
				}
				break;
			}
		}
	}

	*pages_avail = bytes_avail >> PAGE_SHIFT;

	/* Start with page aligned address of last symbol in kernel
	 * image.  The kernel is hard mapped below PAGE_OFFSET in a
	 * 4MB locked TLB translation.
	 */
	start_pfn  = PAGE_ALIGN((unsigned long) &_end) -
		((unsigned long) KERNBASE);

	/* Adjust up to the physical address where the kernel begins. */
	start_pfn += phys_base;

	/* Now shift down to get the real physical page frame number. */
	start_pfn >>= PAGE_SHIFT;
	
	bootmap_pfn = start_pfn;

	end_pfn = end_of_phys_memory >> PAGE_SHIFT;

#ifdef CONFIG_BLK_DEV_INITRD
	/* Now have to check initial ramdisk, so that bootmap does not overwrite it */
	if (sparc_ramdisk_image) {
		if (sparc_ramdisk_image >= (unsigned long)&_end - 2 * PAGE_SIZE)
			sparc_ramdisk_image -= KERNBASE;
		initrd_start = sparc_ramdisk_image + phys_base;
		initrd_end = initrd_start + sparc_ramdisk_size;
		if (initrd_end > end_of_phys_memory) {
			printk(KERN_CRIT "initrd extends beyond end of memory "
		                 	 "(0x%016lx > 0x%016lx)\ndisabling initrd\n",
			       initrd_end, end_of_phys_memory);
			initrd_start = 0;
		}
		if (initrd_start) {
			if (initrd_start >= (start_pfn << PAGE_SHIFT) &&
			    initrd_start < (start_pfn << PAGE_SHIFT) + 2 * PAGE_SIZE)
				bootmap_pfn = PAGE_ALIGN (initrd_end) >> PAGE_SHIFT;
		}
	}
#endif	
	/* Initialize the boot-time allocator. */
	bootmap_size = init_bootmem_node(NODE_DATA(0), bootmap_pfn, phys_base>>PAGE_SHIFT, end_pfn);

	/* Now register the available physical memory with the
	 * allocator.
	 */
	for (i = 0; sp_banks[i].num_bytes != 0; i++)
		free_bootmem(sp_banks[i].base_addr,
			     sp_banks[i].num_bytes);

#ifdef CONFIG_BLK_DEV_INITRD
	if (initrd_start) {
		size = initrd_end - initrd_start;

		/* Resert the initrd image area. */
		reserve_bootmem(initrd_start, size);
		*pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;

		initrd_start += PAGE_OFFSET;
		initrd_end += PAGE_OFFSET;
	}
#endif
	/* Reserve the kernel text/data/bss. */
	size = (start_pfn << PAGE_SHIFT) - phys_base;
	reserve_bootmem(phys_base, size);
	*pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;

	/* Reserve the bootmem map.   We do not account for it
	 * in pages_avail because we will release that memory
	 * in free_all_bootmem.
	 */
	size = bootmap_size;
	reserve_bootmem((bootmap_pfn << PAGE_SHIFT), size);
	*pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;

	return end_pfn;
}

/* paging_init() sets up the page tables */

extern void sun_serial_setup(void);
extern void cheetah_ecache_flush_init(void);

static unsigned long last_valid_pfn;

void __init paging_init(void)
{
	extern pmd_t swapper_pmd_dir[1024];
	extern unsigned int sparc64_vpte_patchme1[1];
	extern unsigned int sparc64_vpte_patchme2[1];
	unsigned long alias_base = phys_base + PAGE_OFFSET;
	unsigned long second_alias_page = 0;
	unsigned long pt, flags, end_pfn, pages_avail;
	unsigned long shift = alias_base - ((unsigned long)KERNBASE);
	unsigned long real_end;

	set_bit(0, mmu_context_bmap);

	real_end = (unsigned long)&_end;
	if ((real_end > ((unsigned long)KERNBASE + 0x400000)))
		bigkernel = 1;
#ifdef CONFIG_BLK_DEV_INITRD
	if (sparc_ramdisk_image)
		real_end = (PAGE_ALIGN(real_end) + PAGE_ALIGN(sparc_ramdisk_size));
#endif

	/* We assume physical memory starts at some 4mb multiple,
	 * if this were not true we wouldn't boot up to this point
	 * anyways.
	 */
	pt  = phys_base | _PAGE_VALID | _PAGE_SZ4MB;
	pt |= _PAGE_CP | _PAGE_CV | _PAGE_P | _PAGE_L | _PAGE_W;
	__save_and_cli(flags);
	if (tlb_type == spitfire) {
		__asm__ __volatile__(
	"	stxa	%1, [%0] %3\n"
	"	stxa	%2, [%5] %4\n"
	"	membar	#Sync\n"
	"	flush	%%g6\n"
	"	nop\n"
	"	nop\n"
	"	nop\n"
		: /* No outputs */
		: "r" (TLB_TAG_ACCESS), "r" (alias_base), "r" (pt),
		  "i" (ASI_DMMU), "i" (ASI_DTLB_DATA_ACCESS), "r" (61 << 3)
		: "memory");
		if (real_end >= KERNBASE + 0x340000) {
			second_alias_page = alias_base + 0x400000;
			__asm__ __volatile__(
		"	stxa	%1, [%0] %3\n"
		"	stxa	%2, [%5] %4\n"
		"	membar	#Sync\n"
		"	flush	%%g6\n"
		"	nop\n"
		"	nop\n"
		"	nop\n"
			: /* No outputs */
			: "r" (TLB_TAG_ACCESS), "r" (second_alias_page), "r" (pt + 0x400000),
			  "i" (ASI_DMMU), "i" (ASI_DTLB_DATA_ACCESS), "r" (60 << 3)
			: "memory");
		}
	} else if (tlb_type == cheetah) {
		__asm__ __volatile__(
	"	stxa	%1, [%0] %3\n"
	"	stxa	%2, [%5] %4\n"
	"	membar	#Sync\n"
	"	flush	%%g6\n"
	"	nop\n"
	"	nop\n"
	"	nop\n"
		: /* No outputs */
		: "r" (TLB_TAG_ACCESS), "r" (alias_base), "r" (pt),
		  "i" (ASI_DMMU), "i" (ASI_DTLB_DATA_ACCESS), "r" ((0<<16) | (13<<3))
		: "memory");
		if (real_end >= KERNBASE + 0x340000) {
			second_alias_page = alias_base + 0x400000;
			__asm__ __volatile__(
		"	stxa	%1, [%0] %3\n"
		"	stxa	%2, [%5] %4\n"
		"	membar	#Sync\n"
		"	flush	%%g6\n"
		"	nop\n"
		"	nop\n"
		"	nop\n"
			: /* No outputs */
			: "r" (TLB_TAG_ACCESS), "r" (second_alias_page), "r" (pt + 0x400000),
			  "i" (ASI_DMMU), "i" (ASI_DTLB_DATA_ACCESS), "r" ((0<<16) | (12<<3))
			: "memory");
		}
	}
	__restore_flags(flags);
	
	/* Now set kernel pgd to upper alias so physical page computations
	 * work.
	 */
	init_mm.pgd += ((shift) / (sizeof(pgd_t)));
	
	memset(swapper_pmd_dir, 0, sizeof(swapper_pmd_dir));

	/* Now can init the kernel/bad page tables. */
	pgd_set(&swapper_pg_dir[0], swapper_pmd_dir + (shift / sizeof(pgd_t)));
	
	sparc64_vpte_patchme1[0] |= (pgd_val(init_mm.pgd[0]) >> 10);
	sparc64_vpte_patchme2[0] |= (pgd_val(init_mm.pgd[0]) & 0x3ff);
	flushi((long)&sparc64_vpte_patchme1[0]);
	
	/* Setup bootmem... */
	pages_avail = 0;
	last_valid_pfn = end_pfn = bootmem_init(&pages_avail);

#ifdef CONFIG_SUN_SERIAL
	/* This does not logically belong here, but we need to
	 * call it at the moment we are able to use the bootmem
	 * allocator.
	 */
	sun_serial_setup();
#endif

	/* Inherit non-locked OBP mappings. */
	inherit_prom_mappings();
	
	/* Ok, we can use our TLB miss and window trap handlers safely.
	 * We need to do a quick peek here to see if we are on StarFire
	 * or not, so setup_tba can setup the IRQ globals correctly (it
	 * needs to get the hard smp processor id correctly).
	 */
	{
		extern void setup_tba(int);
		setup_tba(this_is_starfire);
	}

	inherit_locked_prom_mappings(1);
	
	/* We only created DTLB mapping of this stuff. */
	spitfire_flush_dtlb_nucleus_page(alias_base);
	if (second_alias_page)
		spitfire_flush_dtlb_nucleus_page(second_alias_page);

	__flush_tlb_all();

	{
		unsigned long zones_size[MAX_NR_ZONES];
		unsigned long zholes_size[MAX_NR_ZONES];
		unsigned long npages;
		int znum;

		for (znum = 0; znum < MAX_NR_ZONES; znum++)
			zones_size[znum] = zholes_size[znum] = 0;

		npages = end_pfn - (phys_base >> PAGE_SHIFT);
		zones_size[ZONE_DMA] = npages;
		zholes_size[ZONE_DMA] = npages - pages_avail;

		free_area_init_node(0, NULL, NULL, zones_size,
				    phys_base, zholes_size);
	}

	device_scan();
}

/* Ok, it seems that the prom can allocate some more memory chunks
 * as a side effect of some prom calls we perform during the
 * boot sequence.  My most likely theory is that it is from the
 * prom_set_traptable() call, and OBP is allocating a scratchpad
 * for saving client program register state etc.
 */
void __init sort_memlist(struct linux_mlist_p1275 *thislist)
{
	int swapi = 0;
	int i, mitr;
	unsigned long tmpaddr, tmpsize;
	unsigned long lowest;

	for (i = 0; thislist[i].theres_more != 0; i++) {
		lowest = thislist[i].start_adr;
		for (mitr = i+1; thislist[mitr-1].theres_more != 0; mitr++)
			if (thislist[mitr].start_adr < lowest) {
				lowest = thislist[mitr].start_adr;
				swapi = mitr;
			}
		if (lowest == thislist[i].start_adr)
			continue;
		tmpaddr = thislist[swapi].start_adr;
		tmpsize = thislist[swapi].num_bytes;
		for (mitr = swapi; mitr > i; mitr--) {
			thislist[mitr].start_adr = thislist[mitr-1].start_adr;
			thislist[mitr].num_bytes = thislist[mitr-1].num_bytes;
		}
		thislist[i].start_adr = tmpaddr;
		thislist[i].num_bytes = tmpsize;
	}
}

void __init rescan_sp_banks(void)
{
	struct linux_prom64_registers memlist[64];
	struct linux_mlist_p1275 avail[64], *mlist;
	unsigned long bytes, base_paddr;
	int num_regs, node = prom_finddevice("/memory");
	int i;

	num_regs = prom_getproperty(node, "available",
				    (char *) memlist, sizeof(memlist));
	num_regs = (num_regs / sizeof(struct linux_prom64_registers));
	for (i = 0; i < num_regs; i++) {
		avail[i].start_adr = memlist[i].phys_addr;
		avail[i].num_bytes = memlist[i].reg_size;
		avail[i].theres_more = &avail[i + 1];
	}
	avail[i - 1].theres_more = NULL;
	sort_memlist(avail);

	mlist = &avail[0];
	i = 0;
	bytes = mlist->num_bytes;
	base_paddr = mlist->start_adr;
  
	sp_banks[0].base_addr = base_paddr;
	sp_banks[0].num_bytes = bytes;

	while (mlist->theres_more != NULL){
		i++;
		mlist = mlist->theres_more;
		bytes = mlist->num_bytes;
		if (i >= SPARC_PHYS_BANKS-1) {
			printk ("The machine has more banks than "
				"this kernel can support\n"
				"Increase the SPARC_PHYS_BANKS "
				"setting (currently %d)\n",
				SPARC_PHYS_BANKS);
			i = SPARC_PHYS_BANKS-1;
			break;
		}
    
		sp_banks[i].base_addr = mlist->start_adr;
		sp_banks[i].num_bytes = mlist->num_bytes;
	}

	i++;
	sp_banks[i].base_addr = 0xdeadbeefbeefdeadUL;
	sp_banks[i].num_bytes = 0;

	for (i = 0; sp_banks[i].num_bytes != 0; i++)
		sp_banks[i].num_bytes &= PAGE_MASK;
}

static void __init taint_real_pages(void)
{
	struct sparc_phys_banks saved_sp_banks[SPARC_PHYS_BANKS];
	int i;

	for (i = 0; i < SPARC_PHYS_BANKS; i++) {
		saved_sp_banks[i].base_addr =
			sp_banks[i].base_addr;
		saved_sp_banks[i].num_bytes =
			sp_banks[i].num_bytes;
	}

	rescan_sp_banks();

	/* Find changes discovered in the sp_bank rescan and
	 * reserve the lost portions in the bootmem maps.
	 */
	for (i = 0; saved_sp_banks[i].num_bytes; i++) {
		unsigned long old_start, old_end;

		old_start = saved_sp_banks[i].base_addr;
		old_end = old_start +
			saved_sp_banks[i].num_bytes;
		while (old_start < old_end) {
			int n;

			for (n = 0; sp_banks[n].num_bytes; n++) {
				unsigned long new_start, new_end;

				new_start = sp_banks[n].base_addr;
				new_end = new_start + sp_banks[n].num_bytes;

				if (new_start <= old_start &&
				    new_end >= (old_start + PAGE_SIZE)) {
					set_bit (old_start >> 22,
						 sparc64_valid_addr_bitmap);
					goto do_next_page;
				}
			}
			reserve_bootmem(old_start, PAGE_SIZE);

		do_next_page:
			old_start += PAGE_SIZE;
		}
	}
}

void __init mem_init(void)
{
	unsigned long codepages, datapages, initpages;
	unsigned long addr, last;
	int i;

	i = last_valid_pfn >> ((22 - PAGE_SHIFT) + 6);
	i += 1;
	sparc64_valid_addr_bitmap = (unsigned long *)
		__alloc_bootmem(i << 3, SMP_CACHE_BYTES, 0UL);
	if (sparc64_valid_addr_bitmap == NULL) {
		prom_printf("mem_init: Cannot alloc valid_addr_bitmap.\n");
		prom_halt();
	}
	memset(sparc64_valid_addr_bitmap, 0, i << 3);

	addr = PAGE_OFFSET + phys_base;
	last = PAGE_ALIGN((unsigned long)&_end) -
		((unsigned long) KERNBASE);
	last += PAGE_OFFSET + phys_base;
	while (addr < last) {
		set_bit(__pa(addr) >> 22, sparc64_valid_addr_bitmap);
		addr += PAGE_SIZE;
	}

	taint_real_pages();

	max_mapnr = last_valid_pfn - (phys_base >> PAGE_SHIFT);
	high_memory = __va(last_valid_pfn << PAGE_SHIFT);

	num_physpages = free_all_bootmem() - 1;

	/*
	 * Set up the zero page, mark it reserved, so that page count
	 * is not manipulated when freeing the page from user ptes.
	 */
	mem_map_zero = _alloc_pages(GFP_KERNEL, 0);
	if (mem_map_zero == NULL) {
		prom_printf("paging_init: Cannot alloc zero page.\n");
		prom_halt();
	}
	SetPageReserved(mem_map_zero);
	clear_page(page_address(mem_map_zero));

	codepages = (((unsigned long) &etext) - ((unsigned long)&_start));
	codepages = PAGE_ALIGN(codepages) >> PAGE_SHIFT;
	datapages = (((unsigned long) &edata) - ((unsigned long)&etext));
	datapages = PAGE_ALIGN(datapages) >> PAGE_SHIFT;
	initpages = (((unsigned long) &__init_end) - ((unsigned long) &__init_begin));
	initpages = PAGE_ALIGN(initpages) >> PAGE_SHIFT;

#ifndef CONFIG_SMP
	{
		/* Put empty_pg_dir on pgd_quicklist */
		extern pgd_t empty_pg_dir[1024];
		unsigned long addr = (unsigned long)empty_pg_dir;
		unsigned long alias_base = phys_base + PAGE_OFFSET -
			(long)(KERNBASE);
		
		memset(empty_pg_dir, 0, sizeof(empty_pg_dir));
		addr += alias_base;
		free_pgd_fast((pgd_t *)addr);
		num_physpages++;
	}
#endif

	printk("Memory: %uk available (%ldk kernel code, %ldk data, %ldk init) [%016lx,%016lx]\n",
	       nr_free_pages() << (PAGE_SHIFT-10),
	       codepages << (PAGE_SHIFT-10),
	       datapages << (PAGE_SHIFT-10), 
	       initpages << (PAGE_SHIFT-10), 
	       PAGE_OFFSET, (last_valid_pfn << PAGE_SHIFT));

	if (tlb_type == cheetah)
		cheetah_ecache_flush_init();
}

void free_initmem (void)
{
	unsigned long addr, initend;

	/*
	 * The init section is aligned to 8k in vmlinux.lds. Page align for >8k pagesizes.
	 */
	addr = PAGE_ALIGN((unsigned long)(&__init_begin));
	initend = (unsigned long)(&__init_end) & PAGE_MASK;
	for (; addr < initend; addr += PAGE_SIZE) {
		unsigned long page;
		struct page *p;

		page = (addr +
			((unsigned long) __va(phys_base)) -
			((unsigned long) KERNBASE));
		p = virt_to_page(page);

		ClearPageReserved(p);
		set_page_count(p, 1);
		__free_page(p);
		num_physpages++;
	}
}

#ifdef CONFIG_BLK_DEV_INITRD
void free_initrd_mem(unsigned long start, unsigned long end)
{
	if (start < end)
		printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
	for (; start < end; start += PAGE_SIZE) {
		struct page *p = virt_to_page(start);

		ClearPageReserved(p);
		set_page_count(p, 1);
		__free_page(p);
		num_physpages++;
	}
}
#endif

void si_meminfo(struct sysinfo *val)
{
	val->totalram = num_physpages;
	val->sharedram = 0;
	val->freeram = nr_free_pages();
	val->bufferram = atomic_read(&buffermem_pages);

	/* These are always zero on Sparc64. */
	val->totalhigh = 0;
	val->freehigh = 0;

	val->mem_unit = PAGE_SIZE;
}
