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/*
* 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));
set_page_count(virt_to_page(start), 1);
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));
set_page_count(virt_to_page(start), 1);
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 */
#
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