/* $Id: init.c,v 1.19 2004/02/21 04:42:16 kkojima Exp $
*
* linux/arch/sh/mm/init.c
*
* Copyright (C) 1999 Niibe Yutaka
* Copyright (C) 2002, 2004 Paul Mundt
*
* Based on linux/arch/i386/mm/init.c:
* Copyright (C) 1995 Linus Torvalds
*/
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/types.h>
#include <linux/ptrace.h>
#include <linux/mman.h>
#include <linux/mm.h>
#include <linux/swap.h>
#include <linux/smp.h>
#include <linux/init.h>
#include <linux/highmem.h>
#include <linux/bootmem.h>
#include <linux/pagemap.h>
#include <asm/processor.h>
#include <asm/system.h>
#include <asm/uaccess.h>
#include <asm/pgtable.h>
#include <asm/pgalloc.h>
#include <asm/mmu_context.h>
#include <asm/io.h>
#include <asm/tlb.h>
#include <asm/cacheflush.h>
#include <asm/cache.h>
DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
pgd_t swapper_pg_dir[PTRS_PER_PGD];
/*
* Cache of MMU context last used.
*/
unsigned long mmu_context_cache = NO_CONTEXT;
#ifdef CONFIG_MMU
/* It'd be good if these lines were in the standard header file. */
#define START_PFN (NODE_DATA(0)->bdata->node_boot_start >> PAGE_SHIFT)
#define MAX_LOW_PFN (NODE_DATA(0)->bdata->node_low_pfn)
#endif
void (*copy_page)(void *from, void *to);
void (*clear_page)(void *to);
void show_mem(void)
{
int i, total = 0, reserved = 0;
int shared = 0, cached = 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 (PageReserved(mem_map+i))
reserved++;
else if (PageSwapCache(mem_map+i))
cached++;
else if (page_count(mem_map+i))
shared += page_count(mem_map+i) - 1;
}
printk("%d pages of RAM\n",total);
printk("%d reserved pages\n",reserved);
printk("%d pages shared\n",shared);
printk("%d pages swap cached\n",cached);
}
static void set_pte_phys(unsigned long addr, unsigned long phys, pgprot_t prot)
{
pgd_t *pgd;
pud_t *pud;
pmd_t *pmd;
pte_t *pte;
pgd = swapper_pg_dir + pgd_index(addr);
if (pgd_none(*pgd)) {
pgd_ERROR(*pgd);
return;
}
pud = pud_offset(pgd, addr);
if (pud_none(*pud)) {
pmd = (pmd_t *)get_zeroed_page(GFP_ATOMIC);
set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE | _PAGE_USER));
if (pmd != pmd_offset(pud, 0)) {
pud_ERROR(*pud);
return;
}
}
pmd = pmd_offset(pud, addr);
if (pmd_none(*pmd)) {
pte = (pte_t *)get_zeroed_page(GFP_ATOMIC);
set_pmd(pmd, __pmd(__pa(pte) | _KERNPG_TABLE | _PAGE_USER));
if (pte != pte_offset_kernel(pmd, 0)) {
pmd_ERROR(*pmd);
return;
}
}
pte = pte_offset_kernel(pmd, addr);
if (!pte_none(*pte)) {
pte_ERROR(*pte);
return;
}
set_pte(pte, pfn_pte(phys >> PAGE_SHIFT, prot));
__flush_tlb_page(get_asid(), addr);
}
/*
* As a performance optimization, other platforms preserve the fixmap mapping
* across a context switch, we don't presently do this, but this could be done
* in a similar fashion as to the wired TLB interface that sh64 uses (by way
* of the memorry mapped UTLB configuration) -- this unfortunately forces us to
* give up a TLB entry for each mapping we want to preserve. While this may be
* viable for a small number of fixmaps, it's not particularly useful for
* everything and needs to be carefully evaluated. (ie, we may want this for
* the vsyscall page).
*
* XXX: Perhaps add a _PAGE_WIRED flag or something similar that we can pass
* in at __set_fixmap() time to determine the appropriate behavior to follow.
*
* -- PFM.
*/
void __set_fixmap(enum fixed_addresses idx, unsigned long phys, pgprot_t prot)
{
unsigned long address = __fix_to_virt(idx);
if (idx >= __end_of_fixed_addresses) {
BUG();
return;
}
set_pte_phys(address, phys, prot);
}
/* References to section boundaries */
extern char _text, _etext, _edata, __bss_start, _end;
extern char __init_begin, __init_end;
/*
* paging_init() sets up the page tables
*
* This routines also unmaps the page at virtual kernel address 0, so
* that we can trap those pesky NULL-reference errors in the kernel.
*/
void __init paging_init(void)
{
unsigned long zones_size[MAX_NR_ZONES] = { 0, };
/*
* Setup some defaults for the zone sizes.. these should be safe
* regardless of distcontiguous memory or MMU settings.
*/
zones_size[ZONE_DMA] = 0 >> PAGE_SHIFT;
zones_size[ZONE_NORMAL] = __MEMORY_SIZE >> PAGE_SHIFT;
#ifdef CONFIG_HIGHMEM
zones_size[ZONE_HIGHMEM] = 0 >> PAGE_SHIFT;
#endif
#ifdef CONFIG_MMU
/*
* If we have an MMU, and want to be using it .. we need to adjust
* the zone sizes accordingly, in addition to turning it on.
*/
{
unsigned long max_dma, low, start_pfn;
pgd_t *pg_dir;
int i;
/* We don't need kernel mapping as hardware support that. */
pg_dir = swapper_pg_dir;
for (i = 0; i < PTRS_PER_PGD; i++)
pgd_val(pg_dir[i]) = 0;
/* Turn on the MMU */
enable_mmu();
/* Fixup the zone sizes */
start_pfn = START_PFN;
max_dma = virt_to_phys((char *)MAX_DMA_ADDRESS) >> PAGE_SHIFT;
low = MAX_LOW_PFN;
if (low < max_dma) {
zones_size[ZONE_DMA] = low - start_pfn;
zones_size[ZONE_NORMAL] = 0;
} else {
zones_size[ZONE_DMA] = max_dma - start_pfn;
zones_size[ZONE_NORMAL] = low - max_dma;
}
}
#elif defined(CONFIG_CPU_SH3) || defined(CONFIG_CPU_SH4)
/*
* If we don't have CONFIG_MMU set and the processor in question
* still has an MMU, care needs to be taken to make sure it doesn't
* stay on.. Since the boot loader could have potentially already
* turned it on, and we clearly don't want it, we simply turn it off.
*
* We don't need to do anything special for the zone sizes, since the
* default values that were already configured up above should be
* satisfactory.
*/
disable_mmu();
#endif
NODE_DATA(0)->node_mem_map = NULL;
free_area_init_node(0, NODE_DATA(0), zones_size, __MEMORY_START >> PAGE_SHIFT, 0);
}
void __init mem_init(void)
{
extern unsigned long empty_zero_page[1024];
int codesize, reservedpages, datasize, initsize;
int tmp;
extern unsigned long memory_start;
#ifdef CONFIG_MMU
high_memory = (void *)__va(MAX_LOW_PFN * PAGE_SIZE);
#else
extern unsigned long memory_end;
high_memory = (void *)(memory_end & PAGE_MASK);
#endif
max_mapnr = num_physpages = MAP_NR(high_memory) - MAP_NR(memory_start);
/* clear the zero-page */
memset(empty_zero_page, 0, PAGE_SIZE);
__flush_wback_region(empty_zero_page, PAGE_SIZE);
/*
* Setup wrappers for copy/clear_page(), these will get overridden
* later in the boot process if a better method is available.
*/
#ifdef CONFIG_MMU
copy_page = copy_page_slow;
clear_page = clear_page_slow;
#else
copy_page = copy_page_nommu;
clear_page = clear_page_nommu;
#endif
/* this will put all low memory onto the freelists */
totalram_pages += free_all_bootmem_node(NODE_DATA(0));
reservedpages = 0;
for (tmp = 0; tmp < num_physpages; tmp++)
/*
* Only count reserved RAM pages
*/
if (PageReserved(mem_map+tmp))
reservedpages++;
codesize = (unsigned long) &_etext - (unsigned long) &_text;
datasize = (unsigned long) &_edata - (unsigned long) &_etext;
initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin;
printk("Memory: %luk/%luk available (%dk kernel code, %dk reserved, %dk data, %dk init)\n",
(unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
max_mapnr << (PAGE_SHIFT-10),
codesize >> 10,
reservedpages << (PAGE_SHIFT-10),
datasize >> 10,
initsize >> 10);
p3_cache_init();
}
void free_initmem(void)
{
unsigned long addr;
addr = (unsigned long)(&__init_begin);
for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
ClearPageReserved(virt_to_page(addr));
init_page_count(virt_to_page(addr));
free_page(addr);
totalram_pages++;
}
printk ("Freeing unused kernel memory: %dk freed\n", (&__init_end - &__init_begin) >> 10);
}
#ifdef CONFIG_BLK_DEV_INITRD
void free_initrd_mem(unsigned long start, unsigned long end)
{
unsigned long p;
for (p = start; p < end; p += PAGE_SIZE) {
ClearPageReserved(virt_to_page(p));
init_page_count(virt_to_page(p));
free_page(p);
totalram_pages++;
}
printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
}
#endif
