[deliverable/linux.git] / arch / ppc / mm / init.c

/*
 *  PowerPC version
 *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
 *
 *  Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
 *  and Cort Dougan (PReP) (cort@cs.nmt.edu)
 *    Copyright (C) 1996 Paul Mackerras
 *  Amiga/APUS changes by Jesper Skov (jskov@cygnus.co.uk).
 *  PPC44x/36-bit changes by Matt Porter (mporter@mvista.com)
 *
 *  Derived from "arch/i386/mm/init.c"
 *    Copyright (C) 1991, 1992, 1993, 1994  Linus Torvalds
 *
 *  This program is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU General Public License
 *  as published by the Free Software Foundation; either version
 *  2 of the License, or (at your option) any later version.
 *
 */

#include <linux/module.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/types.h>
#include <linux/mm.h>
#include <linux/stddef.h>
#include <linux/init.h>
#include <linux/bootmem.h>
#include <linux/highmem.h>
#include <linux/initrd.h>
#include <linux/pagemap.h>

#include <asm/pgalloc.h>
#include <asm/prom.h>
#include <asm/io.h>
#include <asm/mmu_context.h>
#include <asm/pgtable.h>
#include <asm/mmu.h>
#include <asm/smp.h>
#include <asm/machdep.h>
#include <asm/btext.h>
#include <asm/tlb.h>
#include <asm/bootinfo.h>

#include "mem_pieces.h"
#include "mmu_decl.h"

#if defined(CONFIG_KERNEL_START_BOOL) || defined(CONFIG_LOWMEM_SIZE_BOOL)
/* The amount of lowmem must be within 0xF0000000 - KERNELBASE. */
#if (CONFIG_LOWMEM_SIZE > (0xF0000000 - KERNELBASE))
#error "You must adjust CONFIG_LOWMEM_SIZE or CONFIG_START_KERNEL"
#endif
#endif
#define MAX_LOW_MEM	CONFIG_LOWMEM_SIZE

DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);

unsigned long total_memory;
unsigned long total_lowmem;

unsigned long ppc_memstart;
unsigned long ppc_memoffset = PAGE_OFFSET;

int mem_init_done;
int init_bootmem_done;
int boot_mapsize;

extern char _end[];
extern char etext[], _stext[];
extern char __init_begin, __init_end;

#ifdef CONFIG_HIGHMEM
pte_t *kmap_pte;
pgprot_t kmap_prot;

EXPORT_SYMBOL(kmap_prot);
EXPORT_SYMBOL(kmap_pte);
#endif

void MMU_init(void);
void set_phys_avail(unsigned long total_ram);

/* XXX should be in current.h  -- paulus */
extern struct task_struct *current_set[NR_CPUS];

char *klimit = _end;
struct mem_pieces phys_avail;

/*
 * this tells the system to map all of ram with the segregs
 * (i.e. page tables) instead of the bats.
 * -- Cort
 */
int __map_without_bats;
int __map_without_ltlbs;

/* max amount of RAM to use */
unsigned long __max_memory;
/* max amount of low RAM to map in */
unsigned long __max_low_memory = MAX_LOW_MEM;

void show_mem(void)
{
	int i,free = 0,total = 0,reserved = 0;
	int shared = 0, cached = 0;
	int highmem = 0;

	printk("Mem-info:\n");
	show_free_areas();
	printk("Free swap:       %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
	i = max_mapnr;
	while (i-- > 0) {
		total++;
		if (PageHighMem(mem_map+i))
			highmem++;
		if (PageReserved(mem_map+i))
			reserved++;
		else if (PageSwapCache(mem_map+i))
			cached++;
		else if (!page_count(mem_map+i))
			free++;
		else
			shared += page_count(mem_map+i) - 1;
	}
	printk("%d pages of RAM\n",total);
	printk("%d pages of HIGHMEM\n", highmem);
	printk("%d free pages\n",free);
	printk("%d reserved pages\n",reserved);
	printk("%d pages shared\n",shared);
	printk("%d pages swap cached\n",cached);
}

/* Free up now-unused memory */
static void free_sec(unsigned long start, unsigned long end, const char *name)
{
	unsigned long cnt = 0;

	while (start < end) {
		ClearPageReserved(virt_to_page(start));
		init_page_count(virt_to_page(start));
		free_page(start);
		cnt++;
		start += PAGE_SIZE;
 	}
	if (cnt) {
		printk(" %ldk %s", cnt << (PAGE_SHIFT - 10), name);
		totalram_pages += cnt;
	}
}

void free_initmem(void)
{
#define FREESEC(TYPE) \
	free_sec((unsigned long)(&__ ## TYPE ## _begin), \
		 (unsigned long)(&__ ## TYPE ## _end), \
		 #TYPE);

	printk ("Freeing unused kernel memory:");
	FREESEC(init);
 	printk("\n");
	ppc_md.progress = NULL;
#undef FREESEC
}

#ifdef CONFIG_BLK_DEV_INITRD
void free_initrd_mem(unsigned long start, unsigned long end)
{
	printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);

	for (; start < end; start += PAGE_SIZE) {
		ClearPageReserved(virt_to_page(start));
		init_page_count(virt_to_page(start));
		free_page(start);
		totalram_pages++;
	}
}
#endif

/*
 * Check for command-line options that affect what MMU_init will do.
 */
void MMU_setup(void)
{
	/* Check for nobats option (used in mapin_ram). */
	if (strstr(cmd_line, "nobats")) {
		__map_without_bats = 1;
	}

	if (strstr(cmd_line, "noltlbs")) {
		__map_without_ltlbs = 1;
	}

	/* Look for mem= option on command line */
	if (strstr(cmd_line, "mem=")) {
		char *p, *q;
		unsigned long maxmem = 0;

		for (q = cmd_line; (p = strstr(q, "mem=")) != 0; ) {
			q = p + 4;
			if (p > cmd_line && p[-1] != ' ')
				continue;
			maxmem = simple_strtoul(q, &q, 0);
			if (*q == 'k' || *q == 'K') {
				maxmem <<= 10;
				++q;
			} else if (*q == 'm' || *q == 'M') {
				maxmem <<= 20;
				++q;
			}
		}
		__max_memory = maxmem;
	}
}

/*
 * MMU_init sets up the basic memory mappings for the kernel,
 * including both RAM and possibly some I/O regions,
 * and sets up the page tables and the MMU hardware ready to go.
 */
void __init MMU_init(void)
{
	if (ppc_md.progress)
		ppc_md.progress("MMU:enter", 0x111);

	/* parse args from command line */
	MMU_setup();

	/*
	 * Figure out how much memory we have, how much
	 * is lowmem, and how much is highmem.  If we were
	 * passed the total memory size from the bootloader,
	 * just use it.
	 */
	if (boot_mem_size)
		total_memory = boot_mem_size;
	else
		total_memory = ppc_md.find_end_of_memory();

	if (__max_memory && total_memory > __max_memory)
		total_memory = __max_memory;
	total_lowmem = total_memory;
#ifdef CONFIG_FSL_BOOKE
	/* Freescale Book-E parts expect lowmem to be mapped by fixed TLB
	 * entries, so we need to adjust lowmem to match the amount we can map
	 * in the fixed entries */
	adjust_total_lowmem();
#endif /* CONFIG_FSL_BOOKE */
	if (total_lowmem > __max_low_memory) {
		total_lowmem = __max_low_memory;
#ifndef CONFIG_HIGHMEM
		total_memory = total_lowmem;
#endif /* CONFIG_HIGHMEM */
	}
	set_phys_avail(total_lowmem);

	/* Initialize the MMU hardware */
	if (ppc_md.progress)
		ppc_md.progress("MMU:hw init", 0x300);
	MMU_init_hw();

	/* Map in all of RAM starting at KERNELBASE */
	if (ppc_md.progress)
		ppc_md.progress("MMU:mapin", 0x301);
	mapin_ram();

#ifdef CONFIG_HIGHMEM
	ioremap_base = PKMAP_BASE;
#else
	ioremap_base = 0xfe000000UL;	/* for now, could be 0xfffff000 */
#endif /* CONFIG_HIGHMEM */
	ioremap_bot = ioremap_base;

	/* Map in I/O resources */
	if (ppc_md.progress)
		ppc_md.progress("MMU:setio", 0x302);
	if (ppc_md.setup_io_mappings)
		ppc_md.setup_io_mappings();

	/* Initialize the context management stuff */
	mmu_context_init();

	if (ppc_md.progress)
		ppc_md.progress("MMU:exit", 0x211);

#ifdef CONFIG_BOOTX_TEXT
	/* By default, we are no longer mapped */
       	boot_text_mapped = 0;
	/* Must be done last, or ppc_md.progress will die. */
	map_boot_text();
#endif
}

/* This is only called until mem_init is done. */
void __init *early_get_page(void)
{
	void *p;

	if (init_bootmem_done) {
		p = alloc_bootmem_pages(PAGE_SIZE);
	} else {
		p = mem_pieces_find(PAGE_SIZE, PAGE_SIZE);
	}
	return p;
}

/*
 * Initialize the bootmem system and give it all the memory we
 * have available.
 */
void __init do_init_bootmem(void)
{
	unsigned long start, size;
	int i;

	/*
	 * Find an area to use for the bootmem bitmap.
	 * We look for the first area which is at least
	 * 128kB in length (128kB is enough for a bitmap
	 * for 4GB of memory, using 4kB pages), plus 1 page
	 * (in case the address isn't page-aligned).
	 */
	start = 0;
	size = 0;
	for (i = 0; i < phys_avail.n_regions; ++i) {
		unsigned long a = phys_avail.regions[i].address;
		unsigned long s = phys_avail.regions[i].size;
		if (s <= size)
			continue;
		start = a;
		size = s;
		if (s >= 33 * PAGE_SIZE)
			break;
	}
	start = PAGE_ALIGN(start);

	min_low_pfn = start >> PAGE_SHIFT;
	max_low_pfn = (PPC_MEMSTART + total_lowmem) >> PAGE_SHIFT;
	max_pfn = (PPC_MEMSTART + total_memory) >> PAGE_SHIFT;
	boot_mapsize = init_bootmem_node(&contig_page_data, min_low_pfn,
					 PPC_MEMSTART >> PAGE_SHIFT,
					 max_low_pfn);

	/* remove the bootmem bitmap from the available memory */
	mem_pieces_remove(&phys_avail, start, boot_mapsize, 1);

	/* add everything in phys_avail into the bootmem map */
	for (i = 0; i < phys_avail.n_regions; ++i)
		free_bootmem(phys_avail.regions[i].address,
			     phys_avail.regions[i].size);

	init_bootmem_done = 1;
}

/*
 * paging_init() sets up the page tables - in fact we've already done this.
 */
void __init paging_init(void)
{
	unsigned long start_pfn, end_pfn;
	unsigned long max_zone_pfns[MAX_NR_ZONES];
#ifdef CONFIG_HIGHMEM
	map_page(PKMAP_BASE, 0, 0);	/* XXX gross */
	pkmap_page_table = pte_offset_kernel(pmd_offset(pgd_offset_k
			(PKMAP_BASE), PKMAP_BASE), PKMAP_BASE);
	map_page(KMAP_FIX_BEGIN, 0, 0);	/* XXX gross */
	kmap_pte = pte_offset_kernel(pmd_offset(pgd_offset_k
			(KMAP_FIX_BEGIN), KMAP_FIX_BEGIN), KMAP_FIX_BEGIN);
	kmap_prot = PAGE_KERNEL;
#endif /* CONFIG_HIGHMEM */
	/* All pages are DMA-able so we put them all in the DMA zone. */
	start_pfn = __pa(PAGE_OFFSET) >> PAGE_SHIFT;
	end_pfn = start_pfn + (total_memory >> PAGE_SHIFT);
	add_active_range(0, start_pfn, end_pfn);

	memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
#ifdef CONFIG_HIGHMEM
	max_zone_pfns[ZONE_DMA] = total_lowmem >> PAGE_SHIFT;
	max_zone_pfns[ZONE_HIGHMEM] = total_memory >> PAGE_SHIFT;
#else
	max_zone_pfns[ZONE_DMA] = total_memory >> PAGE_SHIFT;
#endif /* CONFIG_HIGHMEM */
	free_area_init_nodes(max_zone_pfns);
}

void __init mem_init(void)
{
	unsigned long addr;
	int codepages = 0;
	int datapages = 0;
	int initpages = 0;
#ifdef CONFIG_HIGHMEM
	unsigned long highmem_mapnr;

	highmem_mapnr = total_lowmem >> PAGE_SHIFT;
#endif /* CONFIG_HIGHMEM */
	max_mapnr = total_memory >> PAGE_SHIFT;

	high_memory = (void *) __va(PPC_MEMSTART + total_lowmem);
	num_physpages = max_mapnr;	/* RAM is assumed contiguous */

	totalram_pages += free_all_bootmem();

#ifdef CONFIG_BLK_DEV_INITRD
	/* if we are booted from BootX with an initial ramdisk,
	   make sure the ramdisk pages aren't reserved. */
	if (initrd_start) {
		for (addr = initrd_start; addr < initrd_end; addr += PAGE_SIZE)
			ClearPageReserved(virt_to_page(addr));
	}
#endif /* CONFIG_BLK_DEV_INITRD */

	for (addr = PAGE_OFFSET; addr < (unsigned long)high_memory;
	     addr += PAGE_SIZE) {
		if (!PageReserved(virt_to_page(addr)))
			continue;
		if (addr < (ulong) etext)
			codepages++;
		else if (addr >= (unsigned long)&__init_begin
			 && addr < (unsigned long)&__init_end)
			initpages++;
		else if (addr < (ulong) klimit)
			datapages++;
	}

#ifdef CONFIG_HIGHMEM
	{
		unsigned long pfn;

		for (pfn = highmem_mapnr; pfn < max_mapnr; ++pfn) {
			struct page *page = mem_map + pfn;

			ClearPageReserved(page);
			init_page_count(page);
			__free_page(page);
			totalhigh_pages++;
		}
		totalram_pages += totalhigh_pages;
	}
#endif /* CONFIG_HIGHMEM */

        printk("Memory: %luk available (%dk kernel code, %dk data, %dk init, %ldk highmem)\n",
	       (unsigned long)nr_free_pages()<< (PAGE_SHIFT-10),
	       codepages<< (PAGE_SHIFT-10), datapages<< (PAGE_SHIFT-10),
	       initpages<< (PAGE_SHIFT-10),
	       (unsigned long) (totalhigh_pages << (PAGE_SHIFT-10)));

	mem_init_done = 1;
}

/*
 * Set phys_avail to the amount of physical memory,
 * less the kernel text/data/bss.
 */
void __init
set_phys_avail(unsigned long total_memory)
{
	unsigned long kstart, ksize;

	/*
	 * Initially, available physical memory is equivalent to all
	 * physical memory.
	 */

	phys_avail.regions[0].address = PPC_MEMSTART;
	phys_avail.regions[0].size = total_memory;
	phys_avail.n_regions = 1;

	/*
	 * Map out the kernel text/data/bss from the available physical
	 * memory.
	 */

	kstart = __pa(_stext);	/* should be 0 */
	ksize = PAGE_ALIGN(klimit - _stext);

	mem_pieces_remove(&phys_avail, kstart, ksize, 0);
	mem_pieces_remove(&phys_avail, 0, 0x4000, 0);

#if defined(CONFIG_BLK_DEV_INITRD)
	/* Remove the init RAM disk from the available memory. */
	if (initrd_start) {
		mem_pieces_remove(&phys_avail, __pa(initrd_start),
				  initrd_end - initrd_start, 1);
	}
#endif /* CONFIG_BLK_DEV_INITRD */
}

/* Mark some memory as reserved by removing it from phys_avail. */
void __init reserve_phys_mem(unsigned long start, unsigned long size)
{
	mem_pieces_remove(&phys_avail, start, size, 1);
}

/*
 * This is called when a page has been modified by the kernel.
 * It just marks the page as not i-cache clean.  We do the i-cache
 * flush later when the page is given to a user process, if necessary.
 */
void flush_dcache_page(struct page *page)
{
	clear_bit(PG_arch_1, &page->flags);
}

void flush_dcache_icache_page(struct page *page)
{
#ifdef CONFIG_BOOKE
	void *start = kmap_atomic(page, KM_PPC_SYNC_ICACHE);
	__flush_dcache_icache(start);
	kunmap_atomic(start, KM_PPC_SYNC_ICACHE);
#elif defined(CONFIG_8xx)
Commit	Line	Data
1da177e4 LT	1	/*
	2	* PowerPC version
	3	* Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
	4	*
	5	* Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
	6	* and Cort Dougan (PReP) (cort@cs.nmt.edu)
	7	* Copyright (C) 1996 Paul Mackerras
	8	* Amiga/APUS changes by Jesper Skov (jskov@cygnus.co.uk).
	9	* PPC44x/36-bit changes by Matt Porter (mporter@mvista.com)
	10	*
	11	* Derived from "arch/i386/mm/init.c"
	12	* Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
	13	*
	14	* This program is free software; you can redistribute it and/or
	15	* modify it under the terms of the GNU General Public License
	16	* as published by the Free Software Foundation; either version
	17	* 2 of the License, or (at your option) any later version.
	18	*
	19	*/
	20
1da177e4 LT	21	#include <linux/module.h>
	22	#include <linux/sched.h>
	23	#include <linux/kernel.h>
	24	#include <linux/errno.h>
	25	#include <linux/string.h>
	26	#include <linux/types.h>
	27	#include <linux/mm.h>
	28	#include <linux/stddef.h>
	29	#include <linux/init.h>
	30	#include <linux/bootmem.h>
	31	#include <linux/highmem.h>
	32	#include <linux/initrd.h>
	33	#include <linux/pagemap.h>
	34
	35	#include <asm/pgalloc.h>
	36	#include <asm/prom.h>
	37	#include <asm/io.h>
	38	#include <asm/mmu_context.h>
	39	#include <asm/pgtable.h>
	40	#include <asm/mmu.h>
	41	#include <asm/smp.h>
	42	#include <asm/machdep.h>
	43	#include <asm/btext.h>
	44	#include <asm/tlb.h>
	45	#include <asm/bootinfo.h>
	46
	47	#include "mem_pieces.h"
	48	#include "mmu_decl.h"
	49
	50	#if defined(CONFIG_KERNEL_START_BOOL) \|\| defined(CONFIG_LOWMEM_SIZE_BOOL)
a8de5ce9	51	/* The amount of lowmem must be within 0xF0000000 - KERNELBASE. */
1da177e4 LT	52	#if (CONFIG_LOWMEM_SIZE > (0xF0000000 - KERNELBASE))
	53	#error "You must adjust CONFIG_LOWMEM_SIZE or CONFIG_START_KERNEL"
	54	#endif
	55	#endif
	56	#define MAX_LOW_MEM CONFIG_LOWMEM_SIZE
	57
	58	DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
	59
	60	unsigned long total_memory;
	61	unsigned long total_lowmem;
	62
	63	unsigned long ppc_memstart;
	64	unsigned long ppc_memoffset = PAGE_OFFSET;
	65
	66	int mem_init_done;
	67	int init_bootmem_done;
	68	int boot_mapsize;
1da177e4 LT	69
	70	extern char _end[];
	71	extern char etext[], _stext[];
	72	extern char __init_begin, __init_end;
1da177e4 LT	73
	74	#ifdef CONFIG_HIGHMEM
	75	pte_t *kmap_pte;
	76	pgprot_t kmap_prot;
	77
	78	EXPORT_SYMBOL(kmap_prot);
	79	EXPORT_SYMBOL(kmap_pte);
	80	#endif
	81
	82	void MMU_init(void);
	83	void set_phys_avail(unsigned long total_ram);
	84
	85	/* XXX should be in current.h -- paulus */
	86	extern struct task_struct *current_set[NR_CPUS];
	87
	88	char *klimit = _end;
	89	struct mem_pieces phys_avail;
	90
1da177e4 LT	91	/*
	92	* this tells the system to map all of ram with the segregs
	93	* (i.e. page tables) instead of the bats.
	94	* -- Cort
	95	*/
	96	int __map_without_bats;
	97	int __map_without_ltlbs;
	98
	99	/* max amount of RAM to use */
	100	unsigned long __max_memory;
	101	/* max amount of low RAM to map in */
	102	unsigned long __max_low_memory = MAX_LOW_MEM;
	103
	104	void show_mem(void)
	105	{
	106	int i,free = 0,total = 0,reserved = 0;
	107	int shared = 0, cached = 0;
	108	int highmem = 0;
	109
	110	printk("Mem-info:\n");
	111	show_free_areas();
	112	printk("Free swap: %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
	113	i = max_mapnr;
	114	while (i-- > 0) {
	115	total++;
	116	if (PageHighMem(mem_map+i))
	117	highmem++;
	118	if (PageReserved(mem_map+i))
	119	reserved++;
	120	else if (PageSwapCache(mem_map+i))
	121	cached++;
	122	else if (!page_count(mem_map+i))
	123	free++;
	124	else
	125	shared += page_count(mem_map+i) - 1;
	126	}
	127	printk("%d pages of RAM\n",total);
	128	printk("%d pages of HIGHMEM\n", highmem);
	129	printk("%d free pages\n",free);
	130	printk("%d reserved pages\n",reserved);
	131	printk("%d pages shared\n",shared);
	132	printk("%d pages swap cached\n",cached);
	133	}
	134
	135	/* Free up now-unused memory */
	136	static void free_sec(unsigned long start, unsigned long end, const char *name)
	137	{
	138	unsigned long cnt = 0;
	139
	140	while (start < end) {
	141	ClearPageReserved(virt_to_page(start));
7835e98b	142	init_page_count(virt_to_page(start));
1da177e4 LT	143	free_page(start);
	144	cnt++;
	145	start += PAGE_SIZE;
	146	}
	147	if (cnt) {
	148	printk(" %ldk %s", cnt << (PAGE_SHIFT - 10), name);
	149	totalram_pages += cnt;
	150	}
	151	}
	152
	153	void free_initmem(void)
	154	{
	155	#define FREESEC(TYPE) \
	156	free_sec((unsigned long)(&__ ## TYPE ## _begin), \
	157	(unsigned long)(&__ ## TYPE ## _end), \
	158	#TYPE);
	159
	160	printk ("Freeing unused kernel memory:");
	161	FREESEC(init);
1da177e4	162	printk("\n");
6c37a88c	163	ppc_md.progress = NULL;
1da177e4 LT	164	#undef FREESEC
	165	}
	166
	167	#ifdef CONFIG_BLK_DEV_INITRD
	168	void free_initrd_mem(unsigned long start, unsigned long end)
	169	{
	170	printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
	171
	172	for (; start < end; start += PAGE_SIZE) {
	173	ClearPageReserved(virt_to_page(start));
7835e98b	174	init_page_count(virt_to_page(start));
1da177e4 LT	175	free_page(start);
	176	totalram_pages++;
	177	}
	178	}
	179	#endif
	180
	181	/*
	182	* Check for command-line options that affect what MMU_init will do.
	183	*/
	184	void MMU_setup(void)
	185	{
	186	/* Check for nobats option (used in mapin_ram). */
	187	if (strstr(cmd_line, "nobats")) {
	188	__map_without_bats = 1;
	189	}
	190
	191	if (strstr(cmd_line, "noltlbs")) {
	192	__map_without_ltlbs = 1;
	193	}
	194
	195	/* Look for mem= option on command line */
	196	if (strstr(cmd_line, "mem=")) {
	197	char p, q;
	198	unsigned long maxmem = 0;
	199
	200	for (q = cmd_line; (p = strstr(q, "mem=")) != 0; ) {
	201	q = p + 4;
	202	if (p > cmd_line && p[-1] != ' ')
	203	continue;
	204	maxmem = simple_strtoul(q, &q, 0);
	205	if (q == 'k' \|\| q == 'K') {
	206	maxmem <<= 10;
	207	++q;
	208	} else if (q == 'm' \|\| q == 'M') {
	209	maxmem <<= 20;
	210	++q;
	211	}
	212	}
	213	__max_memory = maxmem;
	214	}
	215	}
	216
	217	/*
	218	* MMU_init sets up the basic memory mappings for the kernel,
	219	* including both RAM and possibly some I/O regions,
	220	* and sets up the page tables and the MMU hardware ready to go.
	221	*/
	222	void __init MMU_init(void)
	223	{
	224	if (ppc_md.progress)
	225	ppc_md.progress("MMU:enter", 0x111);
	226
	227	/* parse args from command line */
	228	MMU_setup();
	229
	230	/*
	231	* Figure out how much memory we have, how much
	232	* is lowmem, and how much is highmem. If we were
	233	* passed the total memory size from the bootloader,
	234	* just use it.
	235	*/
	236	if (boot_mem_size)
	237	total_memory = boot_mem_size;
	238	else
239	total_memory = ppc_md.find_end_of_memory();
240
241	if (__max_memory && total_memory > __max_memory)
242	total_memory = __max_memory;
243	total_lowmem = total_memory;
244	#ifdef CONFIG_FSL_BOOKE
245	/* Freescale Book-E parts expect lowmem to be mapped by fixed TLB
246	* entries, so we need to adjust lowmem to match the amount we can map
247	* in the fixed entries */
248	adjust_total_lowmem();
249	#endif /* CONFIG_FSL_BOOKE */
250	if (total_lowmem > __max_low_memory) {
251	total_lowmem = __max_low_memory;
252	#ifndef CONFIG_HIGHMEM
253	total_memory = total_lowmem;
254	#endif /* CONFIG_HIGHMEM */
255	}
256	set_phys_avail(total_lowmem);
257
258	/* Initialize the MMU hardware */
259	if (ppc_md.progress)
260	ppc_md.progress("MMU:hw init", 0x300);
261	MMU_init_hw();
262
263	/* Map in all of RAM starting at KERNELBASE */
264	if (ppc_md.progress)
265	ppc_md.progress("MMU:mapin", 0x301);
266	mapin_ram();
267
268	#ifdef CONFIG_HIGHMEM
269	ioremap_base = PKMAP_BASE;
270	#else
271	ioremap_base = 0xfe000000UL; /* for now, could be 0xfffff000 */
272	#endif /* CONFIG_HIGHMEM */
273	ioremap_bot = ioremap_base;
274
275	/* Map in I/O resources */
276	if (ppc_md.progress)
277	ppc_md.progress("MMU:setio", 0x302);
278	if (ppc_md.setup_io_mappings)
279	ppc_md.setup_io_mappings();
280
281	/* Initialize the context management stuff */
282	mmu_context_init();
283
284	if (ppc_md.progress)
285	ppc_md.progress("MMU:exit", 0x211);
286
287	#ifdef CONFIG_BOOTX_TEXT
288	/* By default, we are no longer mapped */
289	boot_text_mapped = 0;
290	/* Must be done last, or ppc_md.progress will die. */
291	map_boot_text();
292	#endif
293	}
294
295	/* This is only called until mem_init is done. */
296	void __init *early_get_page(void)
297	{
298	void *p;
299
300	if (init_bootmem_done) {
301	p = alloc_bootmem_pages(PAGE_SIZE);
302	} else {
303	p = mem_pieces_find(PAGE_SIZE, PAGE_SIZE);
304	}
305	return p;
306	}
307
308	/*
309	* Initialize the bootmem system and give it all the memory we
310	* have available.
311	*/
312	void __init do_init_bootmem(void)
313	{
314	unsigned long start, size;
315	int i;
316
317	/*
318	* Find an area to use for the bootmem bitmap.
319	* We look for the first area which is at least
320	* 128kB in length (128kB is enough for a bitmap
321	* for 4GB of memory, using 4kB pages), plus 1 page
322	* (in case the address isn't page-aligned).
323	*/
324	start = 0;
325	size = 0;
326	for (i = 0; i < phys_avail.n_regions; ++i) {
327	unsigned long a = phys_avail.regions[i].address;
328	unsigned long s = phys_avail.regions[i].size;
329	if (s <= size)
330	continue;
331	start = a;
332	size = s;
333	if (s >= 33 * PAGE_SIZE)
334	break;
335	}
336	start = PAGE_ALIGN(start);
337
338	min_low_pfn = start >> PAGE_SHIFT;
339	max_low_pfn = (PPC_MEMSTART + total_lowmem) >> PAGE_SHIFT;
340	max_pfn = (PPC_MEMSTART + total_memory) >> PAGE_SHIFT;
341	boot_mapsize = init_bootmem_node(&contig_page_data, min_low_pfn,
342	PPC_MEMSTART >> PAGE_SHIFT,
343	max_low_pfn);
344
345	/* remove the bootmem bitmap from the available memory */
346	mem_pieces_remove(&phys_avail, start, boot_mapsize, 1);
347
348	/* add everything in phys_avail into the bootmem map */
349	for (i = 0; i < phys_avail.n_regions; ++i)
350	free_bootmem(phys_avail.regions[i].address,
351	phys_avail.regions[i].size);
352
353	init_bootmem_done = 1;
354	}
355
356	/*
357	* paging_init() sets up the page tables - in fact we've already done this.
358	*/
359	void __init paging_init(void)
360	{
c67c3cb4 MG	361	unsigned long start_pfn, end_pfn;
c67c3cb4 MG	362	unsigned long max_zone_pfns[MAX_NR_ZONES];
1da177e4 LT	363	#ifdef CONFIG_HIGHMEM
	364	map_page(PKMAP_BASE, 0, 0); /* XXX gross */
	365	pkmap_page_table = pte_offset_kernel(pmd_offset(pgd_offset_k
	366	(PKMAP_BASE), PKMAP_BASE), PKMAP_BASE);
	367	map_page(KMAP_FIX_BEGIN, 0, 0); /* XXX gross */
	368	kmap_pte = pte_offset_kernel(pmd_offset(pgd_offset_k
	369	(KMAP_FIX_BEGIN), KMAP_FIX_BEGIN), KMAP_FIX_BEGIN);
	370	kmap_prot = PAGE_KERNEL;
	371	#endif /* CONFIG_HIGHMEM */
c67c3cb4 MG	372	/* All pages are DMA-able so we put them all in the DMA zone. */
	373	start_pfn = __pa(PAGE_OFFSET) >> PAGE_SHIFT;
	374	end_pfn = start_pfn + (total_memory >> PAGE_SHIFT);
	375	add_active_range(0, start_pfn, end_pfn);
1da177e4	376
6391af17	377	memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
1da177e4	378	#ifdef CONFIG_HIGHMEM
6391af17 MG	379	max_zone_pfns[ZONE_DMA] = total_lowmem >> PAGE_SHIFT;
6391af17 MG	380	max_zone_pfns[ZONE_HIGHMEM] = total_memory >> PAGE_SHIFT;
c67c3cb4	381	#else
6391af17	382	max_zone_pfns[ZONE_DMA] = total_memory >> PAGE_SHIFT;
1da177e4	383	#endif /* CONFIG_HIGHMEM */
c67c3cb4	384	free_area_init_nodes(max_zone_pfns);
1da177e4 LT	385	}
	386
	387	void __init mem_init(void)
	388	{
	389	unsigned long addr;
	390	int codepages = 0;
	391	int datapages = 0;
	392	int initpages = 0;
	393	#ifdef CONFIG_HIGHMEM
	394	unsigned long highmem_mapnr;
	395
	396	highmem_mapnr = total_lowmem >> PAGE_SHIFT;
	397	#endif /* CONFIG_HIGHMEM */
	398	max_mapnr = total_memory >> PAGE_SHIFT;
	399
	400	high_memory = (void *) __va(PPC_MEMSTART + total_lowmem);
	401	num_physpages = max_mapnr; /* RAM is assumed contiguous */
	402
	403	totalram_pages += free_all_bootmem();
	404
	405	#ifdef CONFIG_BLK_DEV_INITRD
	406	/* if we are booted from BootX with an initial ramdisk,
	407	make sure the ramdisk pages aren't reserved. */
	408	if (initrd_start) {
	409	for (addr = initrd_start; addr < initrd_end; addr += PAGE_SIZE)
	410	ClearPageReserved(virt_to_page(addr));
	411	}
	412	#endif /* CONFIG_BLK_DEV_INITRD */
	413
1da177e4 LT	414	for (addr = PAGE_OFFSET; addr < (unsigned long)high_memory;
	415	addr += PAGE_SIZE) {
	416	if (!PageReserved(virt_to_page(addr)))
	417	continue;
	418	if (addr < (ulong) etext)
	419	codepages++;
	420	else if (addr >= (unsigned long)&__init_begin
	421	&& addr < (unsigned long)&__init_end)
	422	initpages++;
	423	else if (addr < (ulong) klimit)
	424	datapages++;
	425	}
	426
	427	#ifdef CONFIG_HIGHMEM
	428	{
	429	unsigned long pfn;
	430
	431	for (pfn = highmem_mapnr; pfn < max_mapnr; ++pfn) {
	432	struct page *page = mem_map + pfn;
	433
	434	ClearPageReserved(page);
7835e98b	435	init_page_count(page);
1da177e4 LT	436	__free_page(page);
	437	totalhigh_pages++;
	438	}
	439	totalram_pages += totalhigh_pages;
	440	}
	441	#endif /* CONFIG_HIGHMEM */
	442
	443	printk("Memory: %luk available (%dk kernel code, %dk data, %dk init, %ldk highmem)\n",
	444	(unsigned long)nr_free_pages()<< (PAGE_SHIFT-10),
	445	codepages<< (PAGE_SHIFT-10), datapages<< (PAGE_SHIFT-10),
	446	initpages<< (PAGE_SHIFT-10),
	447	(unsigned long) (totalhigh_pages << (PAGE_SHIFT-10)));
6879dc13	448
1da177e4 LT	449	mem_init_done = 1;
	450	}
	451
	452	/*
	453	* Set phys_avail to the amount of physical memory,
	454	* less the kernel text/data/bss.
	455	*/
	456	void __init
	457	set_phys_avail(unsigned long total_memory)
	458	{
	459	unsigned long kstart, ksize;
	460
	461	/*
	462	* Initially, available physical memory is equivalent to all
	463	* physical memory.
	464	*/
	465
	466	phys_avail.regions[0].address = PPC_MEMSTART;
	467	phys_avail.regions[0].size = total_memory;
	468	phys_avail.n_regions = 1;
	469
	470	/*
	471	* Map out the kernel text/data/bss from the available physical
	472	* memory.
	473	*/
	474
	475	kstart = __pa(_stext); /* should be 0 */
	476	ksize = PAGE_ALIGN(klimit - _stext);
	477
	478	mem_pieces_remove(&phys_avail, kstart, ksize, 0);
	479	mem_pieces_remove(&phys_avail, 0, 0x4000, 0);
	480
	481	#if defined(CONFIG_BLK_DEV_INITRD)
	482	/* Remove the init RAM disk from the available memory. */
	483	if (initrd_start) {
	484	mem_pieces_remove(&phys_avail, __pa(initrd_start),
	485	initrd_end - initrd_start, 1);
	486	}
	487	#endif /* CONFIG_BLK_DEV_INITRD */
1da177e4 LT	488	}
	489
	490	/* Mark some memory as reserved by removing it from phys_avail. */
	491	void __init reserve_phys_mem(unsigned long start, unsigned long size)
	492	{
	493	mem_pieces_remove(&phys_avail, start, size, 1);
	494	}
	495
	496	/*
	497	* This is called when a page has been modified by the kernel.
	498	* It just marks the page as not i-cache clean. We do the i-cache
	499	* flush later when the page is given to a user process, if necessary.
	500	*/
	501	void flush_dcache_page(struct page *page)
	502	{
	503	clear_bit(PG_arch_1, &page->flags);
	504	}
	505
	506	void flush_dcache_icache_page(struct page *page)
	507	{
	508	#ifdef CONFIG_BOOKE
5a6a4d43 RD	509	void *start = kmap_atomic(page, KM_PPC_SYNC_ICACHE);
	510	__flush_dcache_icache(start);
	511	kunmap_atomic(start, KM_PPC_SYNC_ICACHE);
cc9c540b	512	#elif defined(CONFIG_8xx)