diff options
Diffstat (limited to 'arch/xtensa/mm/mmu.c')
| -rw-r--r-- | arch/xtensa/mm/mmu.c | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/arch/xtensa/mm/mmu.c b/arch/xtensa/mm/mmu.c index 861203e958d..3429b483d9f 100644 --- a/arch/xtensa/mm/mmu.c +++ b/arch/xtensa/mm/mmu.c @@ -3,6 +3,7 @@ * * Extracted from init.c */ +#include <linux/bootmem.h> #include <linux/percpu.h> #include <linux/init.h> #include <linux/string.h> @@ -16,9 +17,44 @@ #include <asm/initialize_mmu.h> #include <asm/io.h> +#if defined(CONFIG_HIGHMEM) +static void * __init init_pmd(unsigned long vaddr) +{ + pgd_t *pgd = pgd_offset_k(vaddr); + pmd_t *pmd = pmd_offset(pgd, vaddr); + + if (pmd_none(*pmd)) { + unsigned i; + pte_t *pte = alloc_bootmem_low_pages(PAGE_SIZE); + + for (i = 0; i < 1024; i++) + pte_clear(NULL, 0, pte + i); + + set_pmd(pmd, __pmd(((unsigned long)pte) & PAGE_MASK)); + BUG_ON(pte != pte_offset_kernel(pmd, 0)); + pr_debug("%s: vaddr: 0x%08lx, pmd: 0x%p, pte: 0x%p\n", + __func__, vaddr, pmd, pte); + return pte; + } else { + return pte_offset_kernel(pmd, 0); + } +} + +static void __init fixedrange_init(void) +{ + BUILD_BUG_ON(FIXADDR_SIZE > PMD_SIZE); + init_pmd(__fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK); +} +#endif + void __init paging_init(void) { memset(swapper_pg_dir, 0, PAGE_SIZE); +#ifdef CONFIG_HIGHMEM + fixedrange_init(); + pkmap_page_table = init_pmd(PKMAP_BASE); + kmap_init(); +#endif } /* |