[mirror_ubuntu-bionic-kernel.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/config.h>
#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 ammount 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 zones_size[MAX_NR_ZONES], i;

#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.
	 */
	zones_size[ZONE_DMA] = total_lowmem >> PAGE_SHIFT;
	for (i = 1; i < MAX_NR_ZONES; i++)
		zones_size[i] = 0;

#ifdef CONFIG_HIGHMEM
	zones_size[ZONE_HIGHMEM] = (total_memory - total_lowmem) >> PAGE_SHIFT;
#endif /* CONFIG_HIGHMEM */

	free_area_init(zones_size);
}

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 */

#ifdef CONFIG_PPC_OF
	/* mark the RTAS pages as reserved */
	if ( rtas_data )
		for (addr = (ulong)__va(rtas_data);
		     addr < PAGE_ALIGN((ulong)__va(rtas_data)+rtas_size) ;
		     addr += PAGE_SIZE)
			SetPageReserved(virt_to_page(addr));
#endif
	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 */
#ifdef CONFIG_PPC_OF
	/* remove the RTAS pages from the available memory */
	if (rtas_data)
		mem_pieces_remove(&phys_avail, rtas_data, rtas_size, 1);
#endif
}

/* 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
	21	#include <linux/config.h>
	22	#include <linux/module.h>
	23	#include <linux/sched.h>
	24	#include <linux/kernel.h>
	25	#include <linux/errno.h>
	26	#include <linux/string.h>
	27	#include <linux/types.h>
	28	#include <linux/mm.h>
	29	#include <linux/stddef.h>
	30	#include <linux/init.h>
	31	#include <linux/bootmem.h>
	32	#include <linux/highmem.h>
	33	#include <linux/initrd.h>
	34	#include <linux/pagemap.h>
	35
	36	#include <asm/pgalloc.h>
	37	#include <asm/prom.h>
	38	#include <asm/io.h>
	39	#include <asm/mmu_context.h>
	40	#include <asm/pgtable.h>
	41	#include <asm/mmu.h>
	42	#include <asm/smp.h>
	43	#include <asm/machdep.h>
	44	#include <asm/btext.h>
	45	#include <asm/tlb.h>
	46	#include <asm/bootinfo.h>
	47
	48	#include "mem_pieces.h"
	49	#include "mmu_decl.h"
	50
	51	#if defined(CONFIG_KERNEL_START_BOOL) \|\| defined(CONFIG_LOWMEM_SIZE_BOOL)
	52	/* The ammount of lowmem must be within 0xF0000000 - KERNELBASE. */
	53	#if (CONFIG_LOWMEM_SIZE > (0xF0000000 - KERNELBASE))
	54	#error "You must adjust CONFIG_LOWMEM_SIZE or CONFIG_START_KERNEL"
	55	#endif
	56	#endif
	57	#define MAX_LOW_MEM CONFIG_LOWMEM_SIZE
	58
	59	DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
	60
	61	unsigned long total_memory;
	62	unsigned long total_lowmem;
	63
	64	unsigned long ppc_memstart;
65	unsigned long ppc_memoffset = PAGE_OFFSET;
66
67	int mem_init_done;
68	int init_bootmem_done;
69	int boot_mapsize;
1da177e4 LT	70
	71	extern char _end[];
	72	extern char etext[], _stext[];
	73	extern char __init_begin, __init_end;
1da177e4 LT	74
	75	#ifdef CONFIG_HIGHMEM
	76	pte_t *kmap_pte;
	77	pgprot_t kmap_prot;
	78
	79	EXPORT_SYMBOL(kmap_prot);
	80	EXPORT_SYMBOL(kmap_pte);
	81	#endif
	82
	83	void MMU_init(void);
	84	void set_phys_avail(unsigned long total_ram);
	85
	86	/* XXX should be in current.h -- paulus */
	87	extern struct task_struct *current_set[NR_CPUS];
	88
	89	char *klimit = _end;
	90	struct mem_pieces phys_avail;
	91
1da177e4 LT	92	/*
	93	* this tells the system to map all of ram with the segregs
	94	* (i.e. page tables) instead of the bats.
	95	* -- Cort
	96	*/
	97	int __map_without_bats;
	98	int __map_without_ltlbs;
	99
	100	/* max amount of RAM to use */
	101	unsigned long __max_memory;
	102	/* max amount of low RAM to map in */
	103	unsigned long __max_low_memory = MAX_LOW_MEM;
	104
	105	void show_mem(void)
	106	{
	107	int i,free = 0,total = 0,reserved = 0;
	108	int shared = 0, cached = 0;
	109	int highmem = 0;
	110
	111	printk("Mem-info:\n");
	112	show_free_areas();
	113	printk("Free swap: %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
	114	i = max_mapnr;
	115	while (i-- > 0) {
	116	total++;
	117	if (PageHighMem(mem_map+i))
	118	highmem++;
	119	if (PageReserved(mem_map+i))
	120	reserved++;
	121	else if (PageSwapCache(mem_map+i))
	122	cached++;
	123	else if (!page_count(mem_map+i))
	124	free++;
	125	else
	126	shared += page_count(mem_map+i) - 1;
	127	}
	128	printk("%d pages of RAM\n",total);
	129	printk("%d pages of HIGHMEM\n", highmem);
	130	printk("%d free pages\n",free);
	131	printk("%d reserved pages\n",reserved);
	132	printk("%d pages shared\n",shared);
	133	printk("%d pages swap cached\n",cached);
	134	}
	135
	136	/* Free up now-unused memory */
	137	static void free_sec(unsigned long start, unsigned long end, const char *name)
	138	{
	139	unsigned long cnt = 0;
	140
	141	while (start < end) {
	142	ClearPageReserved(virt_to_page(start));
7835e98b	143	init_page_count(virt_to_page(start));
1da177e4 LT	144	free_page(start);
	145	cnt++;
	146	start += PAGE_SIZE;
	147	}
	148	if (cnt) {
	149	printk(" %ldk %s", cnt << (PAGE_SHIFT - 10), name);
	150	totalram_pages += cnt;
	151	}
	152	}
	153
	154	void free_initmem(void)
	155	{
	156	#define FREESEC(TYPE) \
	157	free_sec((unsigned long)(&__ ## TYPE ## _begin), \
	158	(unsigned long)(&__ ## TYPE ## _end), \
	159	#TYPE);
	160
	161	printk ("Freeing unused kernel memory:");
	162	FREESEC(init);
1da177e4	163	printk("\n");
6c37a88c	164	ppc_md.progress = NULL;
1da177e4 LT	165	#undef FREESEC
	166	}
	167
	168	#ifdef CONFIG_BLK_DEV_INITRD
	169	void free_initrd_mem(unsigned long start, unsigned long end)
	170	{
	171	printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
	172
	173	for (; start < end; start += PAGE_SIZE) {
	174	ClearPageReserved(virt_to_page(start));
7835e98b	175	init_page_count(virt_to_page(start));
1da177e4 LT	176	free_page(start);
	177	totalram_pages++;
	178	}
	179	}
	180	#endif
	181
	182	/*
	183	* Check for command-line options that affect what MMU_init will do.
	184	*/
	185	void MMU_setup(void)
	186	{
	187	/* Check for nobats option (used in mapin_ram). */
	188	if (strstr(cmd_line, "nobats")) {
	189	__map_without_bats = 1;
	190	}
	191
	192	if (strstr(cmd_line, "noltlbs")) {
	193	__map_without_ltlbs = 1;
	194	}
	195
	196	/* Look for mem= option on command line */
	197	if (strstr(cmd_line, "mem=")) {
	198	char p, q;
	199	unsigned long maxmem = 0;
	200
	201	for (q = cmd_line; (p = strstr(q, "mem=")) != 0; ) {
	202	q = p + 4;
	203	if (p > cmd_line && p[-1] != ' ')
	204	continue;
	205	maxmem = simple_strtoul(q, &q, 0);
	206	if (q == 'k' \|\| q == 'K') {
	207	maxmem <<= 10;
	208	++q;
	209	} else if (q == 'm' \|\| q == 'M') {
	210	maxmem <<= 20;
	211	++q;
	212	}
	213	}
	214	__max_memory = maxmem;
	215	}
	216	}
	217
	218	/*
	219	* MMU_init sets up the basic memory mappings for the kernel,
	220	* including both RAM and possibly some I/O regions,
	221	* and sets up the page tables and the MMU hardware ready to go.
	222	*/
	223	void __init MMU_init(void)
	224	{
	225	if (ppc_md.progress)
	226	ppc_md.progress("MMU:enter", 0x111);
	227
	228	/* parse args from command line */
	229	MMU_setup();
	230
	231	/*
	232	* Figure out how much memory we have, how much
	233	* is lowmem, and how much is highmem. If we were
	234	* passed the total memory size from the bootloader,
	235	* just use it.
	236	*/
	237	if (boot_mem_size)
	238	total_memory = boot_mem_size;
	239	else
240	total_memory = ppc_md.find_end_of_memory();
241
242	if (__max_memory && total_memory > __max_memory)
243	total_memory = __max_memory;
244	total_lowmem = total_memory;
245	#ifdef CONFIG_FSL_BOOKE
246	/* Freescale Book-E parts expect lowmem to be mapped by fixed TLB
247	* entries, so we need to adjust lowmem to match the amount we can map
248	* in the fixed entries */
249	adjust_total_lowmem();
250	#endif /* CONFIG_FSL_BOOKE */
251	if (total_lowmem > __max_low_memory) {
252	total_lowmem = __max_low_memory;
253	#ifndef CONFIG_HIGHMEM
254	total_memory = total_lowmem;
255	#endif /* CONFIG_HIGHMEM */
256	}
257	set_phys_avail(total_lowmem);
258
259	/* Initialize the MMU hardware */
260	if (ppc_md.progress)
261	ppc_md.progress("MMU:hw init", 0x300);
262	MMU_init_hw();
263
264	/* Map in all of RAM starting at KERNELBASE */
265	if (ppc_md.progress)
266	ppc_md.progress("MMU:mapin", 0x301);
267	mapin_ram();
268
269	#ifdef CONFIG_HIGHMEM
270	ioremap_base = PKMAP_BASE;
271	#else
272	ioremap_base = 0xfe000000UL; /* for now, could be 0xfffff000 */
273	#endif /* CONFIG_HIGHMEM */
274	ioremap_bot = ioremap_base;
275
276	/* Map in I/O resources */
277	if (ppc_md.progress)
278	ppc_md.progress("MMU:setio", 0x302);
279	if (ppc_md.setup_io_mappings)
280	ppc_md.setup_io_mappings();
281
282	/* Initialize the context management stuff */
283	mmu_context_init();
284
285	if (ppc_md.progress)
286	ppc_md.progress("MMU:exit", 0x211);
287
288	#ifdef CONFIG_BOOTX_TEXT
289	/* By default, we are no longer mapped */
290	boot_text_mapped = 0;
291	/* Must be done last, or ppc_md.progress will die. */
292	map_boot_text();
293	#endif
294	}
295
296	/* This is only called until mem_init is done. */
297	void __init *early_get_page(void)
298	{
299	void *p;
300
301	if (init_bootmem_done) {
302	p = alloc_bootmem_pages(PAGE_SIZE);
303	} else {
304	p = mem_pieces_find(PAGE_SIZE, PAGE_SIZE);
305	}
306	return p;
307	}
308
309	/*
310	* Initialize the bootmem system and give it all the memory we
311	* have available.
312	*/
313	void __init do_init_bootmem(void)
314	{
315	unsigned long start, size;
316	int i;
317
318	/*
319	* Find an area to use for the bootmem bitmap.
320	* We look for the first area which is at least
321	* 128kB in length (128kB is enough for a bitmap
322	* for 4GB of memory, using 4kB pages), plus 1 page
323	* (in case the address isn't page-aligned).
324	*/
325	start = 0;
326	size = 0;
327	for (i = 0; i < phys_avail.n_regions; ++i) {
328	unsigned long a = phys_avail.regions[i].address;
329	unsigned long s = phys_avail.regions[i].size;
330	if (s <= size)
331	continue;
332	start = a;
333	size = s;
334	if (s >= 33 * PAGE_SIZE)
335	break;
336	}
337	start = PAGE_ALIGN(start);
338
339	min_low_pfn = start >> PAGE_SHIFT;
340	max_low_pfn = (PPC_MEMSTART + total_lowmem) >> PAGE_SHIFT;
341	max_pfn = (PPC_MEMSTART + total_memory) >> PAGE_SHIFT;
342	boot_mapsize = init_bootmem_node(&contig_page_data, min_low_pfn,
343	PPC_MEMSTART >> PAGE_SHIFT,
344	max_low_pfn);
345
346	/* remove the bootmem bitmap from the available memory */
347	mem_pieces_remove(&phys_avail, start, boot_mapsize, 1);
348
349	/* add everything in phys_avail into the bootmem map */
350	for (i = 0; i < phys_avail.n_regions; ++i)
351	free_bootmem(phys_avail.regions[i].address,
352	phys_avail.regions[i].size);
353
354	init_bootmem_done = 1;
355	}
356
357	/*
358	* paging_init() sets up the page tables - in fact we've already done this.
359	*/
360	void __init paging_init(void)
361	{
362	unsigned long zones_size[MAX_NR_ZONES], i;
363
364	#ifdef CONFIG_HIGHMEM
365	map_page(PKMAP_BASE, 0, 0); /* XXX gross */
366	pkmap_page_table = pte_offset_kernel(pmd_offset(pgd_offset_k
367	(PKMAP_BASE), PKMAP_BASE), PKMAP_BASE);
368	map_page(KMAP_FIX_BEGIN, 0, 0); /* XXX gross */
369	kmap_pte = pte_offset_kernel(pmd_offset(pgd_offset_k
370	(KMAP_FIX_BEGIN), KMAP_FIX_BEGIN), KMAP_FIX_BEGIN);
371	kmap_prot = PAGE_KERNEL;
372	#endif /* CONFIG_HIGHMEM */
373
374	/*
375	* All pages are DMA-able so we put them all in the DMA zone.
376	*/
377	zones_size[ZONE_DMA] = total_lowmem >> PAGE_SHIFT;
378	for (i = 1; i < MAX_NR_ZONES; i++)
379	zones_size[i] = 0;
380
381	#ifdef CONFIG_HIGHMEM
382	zones_size[ZONE_HIGHMEM] = (total_memory - total_lowmem) >> PAGE_SHIFT;
383	#endif /* CONFIG_HIGHMEM */
384
385	free_area_init(zones_size);
386	}
387
388	void __init mem_init(void)
389	{
390	unsigned long addr;
391	int codepages = 0;
392	int datapages = 0;
393	int initpages = 0;
394	#ifdef CONFIG_HIGHMEM
395	unsigned long highmem_mapnr;
396
397	highmem_mapnr = total_lowmem >> PAGE_SHIFT;
398	#endif /* CONFIG_HIGHMEM */
399	max_mapnr = total_memory >> PAGE_SHIFT;
400
401	high_memory = (void *) __va(PPC_MEMSTART + total_lowmem);
402	num_physpages = max_mapnr; /* RAM is assumed contiguous */
403
404	totalram_pages += free_all_bootmem();
405
406	#ifdef CONFIG_BLK_DEV_INITRD
407	/* if we are booted from BootX with an initial ramdisk,
408	make sure the ramdisk pages aren't reserved. */
409	if (initrd_start) {
410	for (addr = initrd_start; addr < initrd_end; addr += PAGE_SIZE)
411	ClearPageReserved(virt_to_page(addr));
412	}
413	#endif /* CONFIG_BLK_DEV_INITRD */
414
415	#ifdef CONFIG_PPC_OF
416	/* mark the RTAS pages as reserved */
417	if ( rtas_data )
418	for (addr = (ulong)__va(rtas_data);
419	addr < PAGE_ALIGN((ulong)__va(rtas_data)+rtas_size) ;
420	addr += PAGE_SIZE)
421	SetPageReserved(virt_to_page(addr));
1da177e4	422	#endif
1da177e4 LT	423	for (addr = PAGE_OFFSET; addr < (unsigned long)high_memory;
	424	addr += PAGE_SIZE) {
	425	if (!PageReserved(virt_to_page(addr)))
	426	continue;
	427	if (addr < (ulong) etext)
	428	codepages++;
	429	else if (addr >= (unsigned long)&__init_begin
	430	&& addr < (unsigned long)&__init_end)
	431	initpages++;
	432	else if (addr < (ulong) klimit)
	433	datapages++;
	434	}
	435
	436	#ifdef CONFIG_HIGHMEM
	437	{
	438	unsigned long pfn;
	439
	440	for (pfn = highmem_mapnr; pfn < max_mapnr; ++pfn) {
	441	struct page *page = mem_map + pfn;
	442
	443	ClearPageReserved(page);
7835e98b	444	init_page_count(page);
1da177e4 LT	445	__free_page(page);
	446	totalhigh_pages++;
	447	}
	448	totalram_pages += totalhigh_pages;
	449	}
	450	#endif /* CONFIG_HIGHMEM */
	451
	452	printk("Memory: %luk available (%dk kernel code, %dk data, %dk init, %ldk highmem)\n",
	453	(unsigned long)nr_free_pages()<< (PAGE_SHIFT-10),
	454	codepages<< (PAGE_SHIFT-10), datapages<< (PAGE_SHIFT-10),
	455	initpages<< (PAGE_SHIFT-10),
	456	(unsigned long) (totalhigh_pages << (PAGE_SHIFT-10)));
6879dc13	457
1da177e4 LT	458	mem_init_done = 1;
	459	}
	460
	461	/*
	462	* Set phys_avail to the amount of physical memory,
	463	* less the kernel text/data/bss.
	464	*/
	465	void __init
	466	set_phys_avail(unsigned long total_memory)
	467	{
	468	unsigned long kstart, ksize;
	469
	470	/*
	471	* Initially, available physical memory is equivalent to all
	472	* physical memory.
	473	*/
	474
	475	phys_avail.regions[0].address = PPC_MEMSTART;
	476	phys_avail.regions[0].size = total_memory;
	477	phys_avail.n_regions = 1;
	478
	479	/*
	480	* Map out the kernel text/data/bss from the available physical
	481	* memory.
	482	*/
	483
	484	kstart = __pa(_stext); /* should be 0 */
	485	ksize = PAGE_ALIGN(klimit - _stext);
	486
	487	mem_pieces_remove(&phys_avail, kstart, ksize, 0);
	488	mem_pieces_remove(&phys_avail, 0, 0x4000, 0);
	489
	490	#if defined(CONFIG_BLK_DEV_INITRD)
	491	/* Remove the init RAM disk from the available memory. */
	492	if (initrd_start) {
	493	mem_pieces_remove(&phys_avail, __pa(initrd_start),
	494	initrd_end - initrd_start, 1);
	495	}
	496	#endif /* CONFIG_BLK_DEV_INITRD */
	497	#ifdef CONFIG_PPC_OF
	498	/* remove the RTAS pages from the available memory */
	499	if (rtas_data)
	500	mem_pieces_remove(&phys_avail, rtas_data, rtas_size, 1);
	501	#endif
1da177e4 LT	502	}
	503
	504	/* Mark some memory as reserved by removing it from phys_avail. */
	505	void __init reserve_phys_mem(unsigned long start, unsigned long size)
	506	{
	507	mem_pieces_remove(&phys_avail, start, size, 1);
	508	}
	509
	510	/*
	511	* This is called when a page has been modified by the kernel.
	512	* It just marks the page as not i-cache clean. We do the i-cache
	513	* flush later when the page is given to a user process, if necessary.
	514	*/
	515	void flush_dcache_page(struct page *page)
	516	{
	517	clear_bit(PG_arch_1, &page->flags);
	518	}
	519
	520	void flush_dcache_icache_page(struct page *page)
	521	{
	522	#ifdef CONFIG_BOOKE
5a6a4d43 RD	523	void *start = kmap_atomic(page, KM_PPC_SYNC_ICACHE);
	524	__flush_dcache_icache(start);
	525	kunmap_atomic(start, KM_PPC_SYNC_ICACHE);
cc9c540b	526	#elif defined(CONFIG_8xx)