[deliverable/linux.git] / arch / arm / mm / idmap.c

#include <linux/kernel.h>

#include <asm/cputype.h>
#include <asm/idmap.h>
#include <asm/pgalloc.h>
#include <asm/pgtable.h>
#include <asm/sections.h>

pgd_t *idmap_pgd;

static void idmap_add_pmd(pud_t *pud, unsigned long addr, unsigned long end,
	unsigned long prot)
{
	pmd_t *pmd = pmd_offset(pud, addr);

	addr = (addr & PMD_MASK) | prot;
	pmd[0] = __pmd(addr);
	addr += SECTION_SIZE;
	pmd[1] = __pmd(addr);
	flush_pmd_entry(pmd);
}

static void idmap_add_pud(pgd_t *pgd, unsigned long addr, unsigned long end,
	unsigned long prot)
{
	pud_t *pud = pud_offset(pgd, addr);
	unsigned long next;

	do {
		next = pud_addr_end(addr, end);
		idmap_add_pmd(pud, addr, next, prot);
	} while (pud++, addr = next, addr != end);
}

static void identity_mapping_add(pgd_t *pgd, unsigned long addr, unsigned long end)
{
	unsigned long prot, next;

	prot = PMD_TYPE_SECT | PMD_SECT_AP_WRITE;
	if (cpu_architecture() <= CPU_ARCH_ARMv5TEJ && !cpu_is_xscale())
		prot |= PMD_BIT4;

	pgd += pgd_index(addr);
	do {
		next = pgd_addr_end(addr, end);
		idmap_add_pud(pgd, addr, next, prot);
	} while (pgd++, addr = next, addr != end);
}

extern char  __idmap_text_start[], __idmap_text_end[];

static int __init init_static_idmap(void)
{
	phys_addr_t idmap_start, idmap_end;

	idmap_pgd = pgd_alloc(&init_mm);
	if (!idmap_pgd)
		return -ENOMEM;

	/* Add an identity mapping for the physical address of the section. */
	idmap_start = virt_to_phys((void *)__idmap_text_start);
	idmap_end = virt_to_phys((void *)__idmap_text_end);

	pr_info("Setting up static identity map for 0x%llx - 0x%llx\n",
		(long long)idmap_start, (long long)idmap_end);
	identity_mapping_add(idmap_pgd, idmap_start, idmap_end);

	return 0;
}
early_initcall(init_static_idmap);

/*
 * In order to soft-boot, we need to switch to a 1:1 mapping for the
 * cpu_reset functions. This will then ensure that we have predictable
 * results when turning off the mmu.
 */
void setup_mm_for_reboot(void)
{
	/* Clean and invalidate L1. */
	flush_cache_all();

	/* Switch to the identity mapping. */
	cpu_switch_mm(idmap_pgd, &init_mm);

	/* Flush the TLB. */
	local_flush_tlb_all();
}
Commit	Line	Data
614dd058 RK	1	#include <linux/kernel.h>
	2
	3	#include <asm/cputype.h>
8903826d	4	#include <asm/idmap.h>
614dd058 RK	5	#include <asm/pgalloc.h>
614dd058 RK	6	#include <asm/pgtable.h>
8903826d WD	7	#include <asm/sections.h>
	8
	9	pgd_t *idmap_pgd;
614dd058	10
516295e5	11	static void idmap_add_pmd(pud_t *pud, unsigned long addr, unsigned long end,
af3813d6 RK	12	unsigned long prot)
af3813d6 RK	13	{
516295e5	14	pmd_t *pmd = pmd_offset(pud, addr);
af3813d6 RK	15
	16	addr = (addr & PMD_MASK) \| prot;
	17	pmd[0] = __pmd(addr);
	18	addr += SECTION_SIZE;
	19	pmd[1] = __pmd(addr);
	20	flush_pmd_entry(pmd);
	21	}
	22
516295e5 RK	23	static void idmap_add_pud(pgd_t *pgd, unsigned long addr, unsigned long end,
	24	unsigned long prot)
	25	{
	26	pud_t *pud = pud_offset(pgd, addr);
	27	unsigned long next;
	28
	29	do {
	30	next = pud_addr_end(addr, end);
	31	idmap_add_pmd(pud, addr, next, prot);
	32	} while (pud++, addr = next, addr != end);
	33	}
	34
4e8ee7de	35	static void identity_mapping_add(pgd_t *pgd, unsigned long addr, unsigned long end)
614dd058	36	{
af3813d6	37	unsigned long prot, next;
614dd058 RK	38
	39	prot = PMD_TYPE_SECT \| PMD_SECT_AP_WRITE;
	40	if (cpu_architecture() <= CPU_ARCH_ARMv5TEJ && !cpu_is_xscale())
	41	prot \|= PMD_BIT4;
	42
af3813d6 RK	43	pgd += pgd_index(addr);
	44	do {
	45	next = pgd_addr_end(addr, end);
516295e5	46	idmap_add_pud(pgd, addr, next, prot);
af3813d6	47	} while (pgd++, addr = next, addr != end);
614dd058 RK	48	}
614dd058 RK	49
8903826d WD	50	extern char __idmap_text_start[], __idmap_text_end[];
	51
	52	static int __init init_static_idmap(void)
	53	{
	54	phys_addr_t idmap_start, idmap_end;
	55
	56	idmap_pgd = pgd_alloc(&init_mm);
	57	if (!idmap_pgd)
	58	return -ENOMEM;
	59
	60	/* Add an identity mapping for the physical address of the section. */
	61	idmap_start = virt_to_phys((void *)__idmap_text_start);
	62	idmap_end = virt_to_phys((void *)__idmap_text_end);
	63
	64	pr_info("Setting up static identity map for 0x%llx - 0x%llx\n",
	65	(long long)idmap_start, (long long)idmap_end);
	66	identity_mapping_add(idmap_pgd, idmap_start, idmap_end);
	67
	68	return 0;
	69	}
4e8ee7de	70	early_initcall(init_static_idmap);
8903826d	71
614dd058	72	/*
2c8951ab WD	73	* In order to soft-boot, we need to switch to a 1:1 mapping for the
	74	* cpu_reset functions. This will then ensure that we have predictable
	75	* results when turning off the mmu.
614dd058	76	*/
5aafec15	77	void setup_mm_for_reboot(void)
614dd058	78	{
2c8951ab WD	79	/* Clean and invalidate L1. */
	80	flush_cache_all();
	81
	82	/* Switch to the identity mapping. */
	83	cpu_switch_mm(idmap_pgd, &init_mm);
	84
	85	/* Flush the TLB. */
614dd058 RK	86	local_flush_tlb_all();
614dd058 RK	87	}