android_kernel_samsung_hero.../arch/arm/mm/early_ioremap.c
2016-08-17 16:41:52 +08:00

111 lines
2.6 KiB
C

/*
* early_ioremap() support for ARM
*
* Based on existing support in arch/x86/mm/ioremap.c
*
* Restrictions: currently only functional before paging_init()
*/
#include <linux/init.h>
#include <linux/io.h>
#include <asm/fixmap.h>
#include <asm/pgalloc.h>
#include <asm/pgtable.h>
#include <asm/tlbflush.h>
#include <asm/mach/map.h>
static pte_t bm_pte[PTRS_PER_PTE + PTE_HWTABLE_PTRS]
__aligned(PTE_HWTABLE_OFF + PTE_HWTABLE_SIZE) __initdata;
static inline pmd_t * __init early_ioremap_pmd(unsigned long addr)
{
unsigned int index = pgd_index(addr);
pgd_t *pgd = cpu_get_pgd() + index;
pud_t *pud = pud_offset(pgd, addr);
pmd_t *pmd = pmd_offset(pud, addr);
return pmd;
}
static inline pte_t * __init early_ioremap_pte(unsigned long addr)
{
return &bm_pte[pte_index(addr)];
}
void __init early_ioremap_init(void)
{
pmd_t *pmd;
pmd = early_ioremap_pmd(fix_to_virt(FIX_BTMAP_BEGIN));
pmd_populate_kernel(NULL, pmd, bm_pte);
/*
* Make sure we don't span multiple pmds.
*/
BUILD_BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT)
!= (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT));
if (pmd != early_ioremap_pmd(fix_to_virt(FIX_BTMAP_END))) {
WARN_ON(1);
pr_warn("pmd %p != %p\n",
pmd, early_ioremap_pmd(fix_to_virt(FIX_BTMAP_END)));
pr_warn("fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n",
fix_to_virt(FIX_BTMAP_BEGIN));
pr_warn("fix_to_virt(FIX_BTMAP_END): %08lx\n",
fix_to_virt(FIX_BTMAP_END));
pr_warn("FIX_BTMAP_END: %d\n", FIX_BTMAP_END);
pr_warn("FIX_BTMAP_BEGIN: %d\n", FIX_BTMAP_BEGIN);
}
early_ioremap_setup();
}
void __init __early_set_fixmap(enum fixed_addresses idx,
phys_addr_t phys, pgprot_t flags)
{
unsigned long addr = __fix_to_virt(idx);
pte_t *pte;
u64 desc;
if (idx > FIX_KMAP_END) {
BUG();
return;
}
pte = early_ioremap_pte(addr);
if (pgprot_val(flags))
set_pte_at(NULL, addr, pte, pfn_pte(phys >> PAGE_SHIFT, flags));
else
pte_clear(NULL, addr, pte);
flush_tlb_kernel_range(addr, addr + PAGE_SIZE);
desc = *pte;
}
void __init early_ioremap_shutdown(void)
{
int i;
pmd_clear(early_ioremap_pmd(fix_to_virt(FIX_BTMAP_BEGIN)));
/* Create new entries for permanent mappings */
for (i = 0; i < __end_of_permanent_fixed_addresses; i++) {
pte_t *pte;
struct map_desc map;
map.virtual = fix_to_virt(i);
pte = early_ioremap_pte(map.virtual);
/* Only i/o device mappings are supported ATM */
if (pte_none(*pte) ||
(pte_val(*pte) & L_PTE_MT_MASK) != L_PTE_MT_DEV_SHARED)
continue;
map.pfn = pte_pfn(*pte);
map.type = MT_DEVICE;
map.length = PAGE_SIZE;
create_mapping(&map);
}
}