linux-kernel-test/arch/sh/mm/init.c
Paul Mundt dfbb904280 sh: sparsemem support.
This implements basic sparsemem support for SH. Presently this only
uses static sparsemem, and we still permit explicit selection of
flatmem. Those boards that want sparsemem can select it as usual.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2007-06-08 02:43:43 +00:00

266 lines
6.5 KiB
C

/*
* linux/arch/sh/mm/init.c
*
* Copyright (C) 1999 Niibe Yutaka
* Copyright (C) 2002 - 2007 Paul Mundt
*
* Based on linux/arch/i386/mm/init.c:
* Copyright (C) 1995 Linus Torvalds
*/
#include <linux/mm.h>
#include <linux/swap.h>
#include <linux/init.h>
#include <linux/bootmem.h>
#include <linux/proc_fs.h>
#include <linux/pagemap.h>
#include <linux/percpu.h>
#include <linux/io.h>
#include <asm/mmu_context.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];
void (*copy_page)(void *from, void *to);
void (*clear_page)(void *to);
void show_mem(void)
{
int total = 0, reserved = 0, free = 0;
int shared = 0, cached = 0, slab = 0;
pg_data_t *pgdat;
printk("Mem-info:\n");
show_free_areas();
for_each_online_pgdat(pgdat) {
unsigned long flags, i;
pgdat_resize_lock(pgdat, &flags);
for (i = 0; i < pgdat->node_spanned_pages; i++) {
struct page *page = pgdat_page_nr(pgdat, i);
total++;
if (PageReserved(page))
reserved++;
else if (PageSwapCache(page))
cached++;
else if (PageSlab(page))
slab++;
else if (!page_count(page))
free++;
else
shared += page_count(page) - 1;
}
pgdat_resize_unlock(pgdat, &flags);
}
printk("Free swap: %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
printk("%d pages of RAM\n", total);
printk("%d free pages\n", free);
printk("%d reserved pages\n", reserved);
printk("%d slab pages\n", slab);
printk("%d pages shared\n", shared);
printk("%d pages swap cached\n", cached);
printk(KERN_INFO "Total of %ld pages in page table cache\n",
quicklist_total_size());
}
#ifdef CONFIG_MMU
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 = pgd_offset_k(addr);
if (pgd_none(*pgd)) {
pgd_ERROR(*pgd);
return;
}
pud = pud_alloc(NULL, pgd, addr);
if (unlikely(!pud)) {
pud_ERROR(*pud);
return;
}
pmd = pmd_alloc(NULL, pud, addr);
if (unlikely(!pmd)) {
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_one(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 memory 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);
}
#endif /* CONFIG_MMU */
/* 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
*/
void __init paging_init(void)
{
int nid;
/* We don't need to map the kernel through the TLB, as
* it is permanatly mapped using P1. So clear the
* entire pgd. */
memset(swapper_pg_dir, 0, sizeof(swapper_pg_dir));
/* Set an initial value for the MMU.TTB so we don't have to
* check for a null value. */
set_TTB(swapper_pg_dir);
for_each_online_node(nid) {
pg_data_t *pgdat = NODE_DATA(nid);
unsigned long max_zone_pfns[MAX_NR_ZONES];
unsigned long low, start_pfn;
memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
start_pfn = pgdat->bdata->node_boot_start >> PAGE_SHIFT;
low = pgdat->bdata->node_low_pfn;
max_zone_pfns[ZONE_NORMAL] = low;
printk("Node %u: start_pfn = 0x%lx, low = 0x%lx\n",
nid, start_pfn, low);
free_area_init_nodes(max_zone_pfns);
}
}
static struct kcore_list kcore_mem, kcore_vmalloc;
void __init mem_init(void)
{
int codesize, datasize, initsize;
int nid;
for_each_online_node(nid) {
pg_data_t *pgdat = NODE_DATA(nid);
unsigned long node_pages = 0;
void *node_high_memory;
num_physpages += pgdat->node_present_pages;
if (pgdat->node_spanned_pages)
node_pages = free_all_bootmem_node(pgdat);
totalram_pages += node_pages;
node_high_memory = (void *)((pgdat->node_start_pfn +
pgdat->node_spanned_pages) <<
PAGE_SHIFT);
if (node_high_memory > high_memory)
high_memory = node_high_memory;
}
/* 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
codesize = (unsigned long) &_etext - (unsigned long) &_text;
datasize = (unsigned long) &_edata - (unsigned long) &_etext;
initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin;
kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT);
kclist_add(&kcore_vmalloc, (void *)VMALLOC_START,
VMALLOC_END - VMALLOC_START);
printk(KERN_INFO "Memory: %luk/%luk available (%dk kernel code, "
"%dk data, %dk init)\n",
(unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
totalram_pages << (PAGE_SHIFT-10),
codesize >> 10,
datasize >> 10,
initsize >> 10);
p3_cache_init();
/* Initialize the vDSO */
vsyscall_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