linux/arch/mips/mm/pgtable-64.c
David Daney 325f8a0a31 MIPS: Two-level pagetables for 64-bit kernels with 64KB pages.
For 64-bit kernels with 64KB pages and two level page tables, there are
42 bits worth of virtual address space This is larger than the 40 bits of
virtual address space obtained with the default 4KB Page size and three
levels, so there are no draw backs for using two level tables with this
configuration.

Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Cc: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/761/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2010-02-27 12:53:03 +01:00

80 lines
1.6 KiB
C

/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 1999, 2000 by Silicon Graphics
* Copyright (C) 2003 by Ralf Baechle
*/
#include <linux/init.h>
#include <linux/mm.h>
#include <asm/fixmap.h>
#include <asm/pgtable.h>
#include <asm/pgalloc.h>
void pgd_init(unsigned long page)
{
unsigned long *p, *end;
unsigned long entry;
#ifdef __PAGETABLE_PMD_FOLDED
entry = (unsigned long)invalid_pte_table;
#else
entry = (unsigned long)invalid_pmd_table;
#endif
p = (unsigned long *) page;
end = p + PTRS_PER_PGD;
while (p < end) {
p[0] = entry;
p[1] = entry;
p[2] = entry;
p[3] = entry;
p[4] = entry;
p[5] = entry;
p[6] = entry;
p[7] = entry;
p += 8;
}
}
#ifndef __PAGETABLE_PMD_FOLDED
void pmd_init(unsigned long addr, unsigned long pagetable)
{
unsigned long *p, *end;
p = (unsigned long *) addr;
end = p + PTRS_PER_PMD;
while (p < end) {
p[0] = pagetable;
p[1] = pagetable;
p[2] = pagetable;
p[3] = pagetable;
p[4] = pagetable;
p[5] = pagetable;
p[6] = pagetable;
p[7] = pagetable;
p += 8;
}
}
#endif
void __init pagetable_init(void)
{
unsigned long vaddr;
pgd_t *pgd_base;
/* Initialize the entire pgd. */
pgd_init((unsigned long)swapper_pg_dir);
#ifndef __PAGETABLE_PMD_FOLDED
pmd_init((unsigned long)invalid_pmd_table, (unsigned long)invalid_pte_table);
#endif
pgd_base = swapper_pg_dir;
/*
* Fixed mappings:
*/
vaddr = __fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK;
fixrange_init(vaddr, 0, pgd_base);
}