Viewing file:  init.c (15.34 KB) -rw-r--r--
Select action/file-type:
 (+) |  (+) |  (+) | Code (+) | Session (+) |  (+) | SDB (+) |  (+) |  (+) |  (+) |  (+) |  (+) |
/*
* BK Id: SCCS/s.init.c 1.40 01/25/02 15:15:24 benh
*/
/*
* 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).
*
* 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/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>
#ifdef CONFIG_BLK_DEV_INITRD
#include <linux/blk.h> /* for initrd_* */
#endif
#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 "mem_pieces.h"
#include "mmu_decl.h"
mmu_gather_t mmu_gathers[NR_CPUS];
void *end_of_DRAM;
unsigned long total_memory;
unsigned long total_lowmem;
int mem_init_done;
int init_bootmem_done;
int boot_mapsize;
unsigned long totalram_pages;
unsigned long totalhigh_pages;
#ifdef CONFIG_ALL_PPC
unsigned long agp_special_page;
#endif
extern char _end[];
extern char etext[], _stext[];
extern char __init_begin, __init_end;
extern char __prep_begin, __prep_end;
extern char __chrp_begin, __chrp_end;
extern char __pmac_begin, __pmac_end;
extern char __openfirmware_begin, __openfirmware_end;
#ifdef CONFIG_HIGHMEM
pte_t *kmap_pte;
pgprot_t kmap_prot;
#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;
extern char *sysmap;
extern unsigned long sysmap_size;
/*
* 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;
/* max amount of RAM to use */
unsigned long __max_memory;
int do_check_pgt_cache(int low, int high)
{
int freed = 0;
if (pgtable_cache_size > high) {
do {
if (pgd_quicklist) {
free_pgd_slow(get_pgd_fast());
freed++;
}
if (pte_quicklist) {
pte_free_slow(pte_alloc_one_fast(NULL, 0));
freed++;
}
} while (pgtable_cache_size > low);
}
return freed;
}
void show_mem(void)
{
int i,free = 0,total = 0,reserved = 0;
int shared = 0, cached = 0;
struct task_struct *p;
int highmem = 0;
printk("Mem-info:\n");
show_free_areas();
printk("Free swap: %6dkB\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 += atomic_read(&mem_map[i].count) - 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);
printk("%d pages in page table cache\n",(int)pgtable_cache_size);
show_buffers();
printk("%-8s %3s %8s %8s %8s %9s %8s", "Process", "Pid",
"Ctx", "Ctx<<4", "Last Sys", "pc", "task");
#ifdef CONFIG_SMP
printk(" %3s", "CPU");
#endif /* CONFIG_SMP */
printk("\n");
for_each_task(p)
{
printk("%-8.8s %3d %8ld %8ld %8ld %c%08lx %08lx ",
p->comm,p->pid,
(p->mm)?p->mm->context:0,
(p->mm)?(p->mm->context<<4):0,
p->thread.last_syscall,
(p->thread.regs)?user_mode(p->thread.regs) ? 'u' : 'k' : '?',
(p->thread.regs)?p->thread.regs->nip:0,
(ulong)p);
{
int iscur = 0;
#ifdef CONFIG_SMP
printk("%3d ", p->processor);
if ( (p->processor != NO_PROC_ID) &&
(p == current_set[p->processor]) )
{
iscur = 1;
printk("current");
}
#else
if ( p == current )
{
iscur = 1;
printk("current");
}
if ( p == last_task_used_math )
{
if ( iscur )
printk(",");
printk("last math");
}
#endif /* CONFIG_SMP */
printk("\n");
}
}
}
void si_meminfo(struct sysinfo *val)
{
val->totalram = totalram_pages;
val->sharedram = 0;
val->freeram = nr_free_pages();
val->bufferram = atomic_read(&buffermem_pages);
val->totalhigh = totalhigh_pages;
val->freehigh = nr_free_highpages();
val->mem_unit = PAGE_SIZE;
}
/* 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);
if (_machine != _MACH_Pmac)
FREESEC(pmac);
if (_machine != _MACH_chrp)
FREESEC(chrp);
if (_machine != _MACH_prep)
FREESEC(prep);
if (!have_of)
FREESEC(openfirmware);
printk("\n");
#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;
}
/* 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.
*/
total_memory = ppc_md.find_end_of_memory();
if (__max_memory && total_memory > __max_memory)
total_memory = __max_memory;
total_lowmem = total_memory;
adjust_total_lowmem();
end_of_DRAM = __va(total_lowmem);
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);
boot_mapsize = init_bootmem(start >> PAGE_SHIFT,
total_lowmem >> PAGE_SHIFT);
/* 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(pmd_offset(pgd_offset_k(PKMAP_BASE), PKMAP_BASE), PKMAP_BASE);
map_page(KMAP_FIX_BEGIN, 0, 0); /* XXX gross */
kmap_pte = pte_offset(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;
highmem_start_page = mem_map + highmem_mapnr;
max_mapnr = total_memory >> PAGE_SHIFT;
#else
max_mapnr = max_low_pfn;
#endif /* CONFIG_HIGHMEM */
high_memory = (void *) __va(max_low_pfn * PAGE_SIZE);
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 */
#if defined(CONFIG_ALL_PPC)
/* 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));
if (agp_special_page)
SetPageReserved(virt_to_page(agp_special_page));
#endif /* defined(CONFIG_ALL_PPC) */
if ( sysmap )
for (addr = (unsigned long)sysmap;
addr < PAGE_ALIGN((unsigned long)sysmap+sysmap_size) ;
addr += PAGE_SIZE)
SetPageReserved(virt_to_page(addr));
for (addr = PAGE_OFFSET; addr < (unsigned long)end_of_DRAM;
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);
set_bit(PG_highmem, &page->flags);
atomic_set(&page->count, 1);
__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)));
if (sysmap)
printk("System.map loaded at 0x%08x for debugger, size: %ld bytes\n",
(unsigned int)sysmap, sysmap_size);
#if defined(CONFIG_ALL_PPC)
if (agp_special_page)
printk(KERN_INFO "AGP special page: 0x%08lx\n", agp_special_page);
#endif /* defined(CONFIG_ALL_PPC) */
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 = 0;
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_ALL_PPC
/* remove the RTAS pages from the available memory */
if (rtas_data)
mem_pieces_remove(&phys_avail, rtas_data, rtas_size, 1);
/* remove the sysmap pages from the available memory */
if (sysmap)
mem_pieces_remove(&phys_avail, __pa(sysmap), sysmap_size, 1);
/* Because of some uninorth weirdness, we need a page of
* memory as high as possible (it must be outside of the
* bus address seen as the AGP aperture). It will be used
* by the r128 DRM driver
*
* FIXME: We need to make sure that page doesn't overlap any of the\
* above. This could be done by improving mem_pieces_find to be able
* to do a backward search from the end of the list.
*/
if (_machine == _MACH_Pmac && find_devices("uni-north-agp")) {
agp_special_page = (total_memory - PAGE_SIZE);
mem_pieces_remove(&phys_avail, agp_special_page, PAGE_SIZE, 0);
agp_special_page = (unsigned long)__va(agp_special_page);
}
#endif /* CONFIG_ALL_PPC */
}
/* 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);
}
void flush_page_to_ram(struct page *page)
{
unsigned long vaddr = (unsigned long) kmap(page);
__flush_page_to_ram(vaddr);
kunmap(page);
}
/*
* set_pte stores a linux PTE into the linux page table.
* On machines which use an MMU hash table we avoid changing the
* _PAGE_HASHPTE bit.
*/
void set_pte(pte_t *ptep, pte_t pte)
{
#if _PAGE_HASHPTE != 0
pte_update(ptep, ~_PAGE_HASHPTE, pte_val(pte) & ~_PAGE_HASHPTE);
#else
*ptep = pte;
#endif
}
|