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Diffstat (limited to 'arch/mips/include/asm/pgtable-32.h')
| -rw-r--r-- | arch/mips/include/asm/pgtable-32.h | 305 |
1 files changed, 305 insertions, 0 deletions
diff --git a/arch/mips/include/asm/pgtable-32.h b/arch/mips/include/asm/pgtable-32.h new file mode 100644 index 0000000000..0e196650f4 --- /dev/null +++ b/arch/mips/include/asm/pgtable-32.h @@ -0,0 +1,305 @@ +/* + * 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) 1994, 95, 96, 97, 98, 99, 2000, 2003 Ralf Baechle + * Copyright (C) 1999, 2000, 2001 Silicon Graphics, Inc. + */ +#ifndef _ASM_PGTABLE_32_H +#define _ASM_PGTABLE_32_H + +#include <asm/addrspace.h> +#include <asm/page.h> + +#include <linux/linkage.h> +#include <asm/cachectl.h> +#include <asm/fixmap.h> + +#include <asm-generic/pgtable-nopmd.h> + +#ifdef CONFIG_HIGHMEM +#include <asm/highmem.h> +#endif + +/* + * Regarding 32-bit MIPS huge page support (and the tradeoff it entails): + * + * We use the same huge page sizes as 64-bit MIPS. Assuming a 4KB page size, + * our 2-level table layout would normally have a PGD entry cover a contiguous + * 4MB virtual address region (pointing to a 4KB PTE page of 1,024 32-bit pte_t + * pointers, each pointing to a 4KB physical page). The problem is that 4MB, + * spanning both halves of a TLB EntryLo0,1 pair, requires 2MB hardware page + * support, not one of the standard supported sizes (1MB,4MB,16MB,...). + * To correct for this, when huge pages are enabled, we halve the number of + * pointers a PTE page holds, making its last half go to waste. Correspondingly, + * we double the number of PGD pages. Overall, page table memory overhead + * increases to match 64-bit MIPS, but PTE lookups remain CPU cache-friendly. + * + * NOTE: We don't yet support huge pages if extended-addressing is enabled + * (i.e. EVA, XPA, 36-bit Alchemy/Netlogic). + */ + +extern int temp_tlb_entry; + +/* + * - add_temporary_entry() add a temporary TLB entry. We use TLB entries + * starting at the top and working down. This is for populating the + * TLB before trap_init() puts the TLB miss handler in place. It + * should be used only for entries matching the actual page tables, + * to prevent inconsistencies. + */ +extern int add_temporary_entry(unsigned long entrylo0, unsigned long entrylo1, + unsigned long entryhi, unsigned long pagemask); + +/* + * Basically we have the same two-level (which is the logical three level + * Linux page table layout folded) page tables as the i386. Some day + * when we have proper page coloring support we can have a 1% quicker + * tlb refill handling mechanism, but for now it is a bit slower but + * works even with the cache aliasing problem the R4k and above have. + */ + +/* PGDIR_SHIFT determines what a third-level page table entry can map */ +#if defined(CONFIG_MIPS_HUGE_TLB_SUPPORT) && !defined(CONFIG_PHYS_ADDR_T_64BIT) +# define PGDIR_SHIFT (2 * PAGE_SHIFT - PTE_T_LOG2 - 1) +#else +# define PGDIR_SHIFT (2 * PAGE_SHIFT - PTE_T_LOG2) +#endif + +#define PGDIR_SIZE (1UL << PGDIR_SHIFT) +#define PGDIR_MASK (~(PGDIR_SIZE-1)) + +/* + * Entries per page directory level: we use two-level, so + * we don't really have any PUD/PMD directory physically. + */ +#if defined(CONFIG_MIPS_HUGE_TLB_SUPPORT) && !defined(CONFIG_PHYS_ADDR_T_64BIT) +# define __PGD_TABLE_ORDER (32 - 3 * PAGE_SHIFT + PGD_T_LOG2 + PTE_T_LOG2 + 1) +#else +# define __PGD_TABLE_ORDER (32 - 3 * PAGE_SHIFT + PGD_T_LOG2 + PTE_T_LOG2) +#endif + +#define PGD_TABLE_ORDER (__PGD_TABLE_ORDER >= 0 ? __PGD_TABLE_ORDER : 0) +#define PUD_TABLE_ORDER aieeee_attempt_to_allocate_pud +#define PMD_TABLE_ORDER aieeee_attempt_to_allocate_pmd + +#define PTRS_PER_PGD (USER_PTRS_PER_PGD * 2) +#if defined(CONFIG_MIPS_HUGE_TLB_SUPPORT) && !defined(CONFIG_PHYS_ADDR_T_64BIT) +# define PTRS_PER_PTE (PAGE_SIZE / sizeof(pte_t) / 2) +#else +# define PTRS_PER_PTE (PAGE_SIZE / sizeof(pte_t)) +#endif + +#define USER_PTRS_PER_PGD (0x80000000UL/PGDIR_SIZE) + +#define VMALLOC_START MAP_BASE + +#define PKMAP_END ((FIXADDR_START) & ~((LAST_PKMAP << PAGE_SHIFT)-1)) +#define PKMAP_BASE (PKMAP_END - PAGE_SIZE * LAST_PKMAP) + +#ifdef CONFIG_HIGHMEM +# define VMALLOC_END (PKMAP_BASE-2*PAGE_SIZE) +#else +# define VMALLOC_END (FIXADDR_START-2*PAGE_SIZE) +#endif + +#ifdef CONFIG_PHYS_ADDR_T_64BIT +#define pte_ERROR(e) \ + printk("%s:%d: bad pte %016Lx.\n", __FILE__, __LINE__, pte_val(e)) +#else +#define pte_ERROR(e) \ + printk("%s:%d: bad pte %08lx.\n", __FILE__, __LINE__, pte_val(e)) +#endif +#define pgd_ERROR(e) \ + printk("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e)) + +extern void load_pgd(unsigned long pg_dir); + +extern pte_t invalid_pte_table[PTRS_PER_PTE]; + +/* + * Empty pgd/pmd entries point to the invalid_pte_table. + */ +static inline int pmd_none(pmd_t pmd) +{ + return pmd_val(pmd) == (unsigned long) invalid_pte_table; +} + +static inline int pmd_bad(pmd_t pmd) +{ +#ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT + /* pmd_huge(pmd) but inline */ + if (unlikely(pmd_val(pmd) & _PAGE_HUGE)) + return 0; +#endif + + if (unlikely(pmd_val(pmd) & ~PAGE_MASK)) + return 1; + + return 0; +} + +static inline int pmd_present(pmd_t pmd) +{ + return pmd_val(pmd) != (unsigned long) invalid_pte_table; +} + +static inline void pmd_clear(pmd_t *pmdp) +{ + pmd_val(*pmdp) = ((unsigned long) invalid_pte_table); +} + +#if defined(CONFIG_XPA) + +#define MAX_POSSIBLE_PHYSMEM_BITS 40 +#define pte_pfn(x) (((unsigned long)((x).pte_high >> PFN_PTE_SHIFT)) | (unsigned long)((x).pte_low << _PAGE_PRESENT_SHIFT)) +static inline pte_t +pfn_pte(unsigned long pfn, pgprot_t prot) +{ + pte_t pte; + + pte.pte_low = (pfn >> _PAGE_PRESENT_SHIFT) | + (pgprot_val(prot) & ~_PFNX_MASK); + pte.pte_high = (pfn << PFN_PTE_SHIFT) | + (pgprot_val(prot) & ~_PFN_MASK); + return pte; +} + +#elif defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32) + +#define MAX_POSSIBLE_PHYSMEM_BITS 36 +#define pte_pfn(x) ((unsigned long)((x).pte_high >> 6)) + +static inline pte_t pfn_pte(unsigned long pfn, pgprot_t prot) +{ + pte_t pte; + + pte.pte_high = (pfn << 6) | (pgprot_val(prot) & 0x3f); + pte.pte_low = pgprot_val(prot); + + return pte; +} + +#else + +#define MAX_POSSIBLE_PHYSMEM_BITS 32 +#define pte_pfn(x) ((unsigned long)((x).pte >> PFN_PTE_SHIFT)) +#define pfn_pte(pfn, prot) __pte(((unsigned long long)(pfn) << PFN_PTE_SHIFT) | pgprot_val(prot)) +#define pfn_pmd(pfn, prot) __pmd(((unsigned long long)(pfn) << PFN_PTE_SHIFT) | pgprot_val(prot)) +#endif /* defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32) */ + +#define pte_page(x) pfn_to_page(pte_pfn(x)) + +/* + * Encode/decode swap entries and swap PTEs. Swap PTEs are all PTEs that + * are !pte_none() && !pte_present(). + */ +#if defined(CONFIG_CPU_R3K_TLB) + +/* + * Format of swap PTEs: + * + * 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 + * 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 + * <----------- offset ------------> < type -> V G E 0 0 0 0 0 0 P + * + * E is the exclusive marker that is not stored in swap entries. + * _PAGE_PRESENT (P), _PAGE_VALID (V) and_PAGE_GLOBAL (G) have to remain + * unused. + */ +#define __swp_type(x) (((x).val >> 10) & 0x1f) +#define __swp_offset(x) ((x).val >> 15) +#define __swp_entry(type, offset) ((swp_entry_t) { (((type) & 0x1f) << 10) | ((offset) << 15) }) +#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) }) +#define __swp_entry_to_pte(x) ((pte_t) { (x).val }) + +/* We borrow bit 7 to store the exclusive marker in swap PTEs. */ +#define _PAGE_SWP_EXCLUSIVE (1 << 7) + +#else + +#if defined(CONFIG_XPA) + +/* + * Format of swap PTEs: + * + * 6 6 6 6 5 5 5 5 5 5 5 5 5 5 4 4 4 4 4 4 4 4 4 4 3 3 3 3 3 3 3 3 + * 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 + * 0 0 0 0 0 0 E P <------------------ zeroes -------------------> + * + * 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 + * 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 + * <----------------- offset ------------------> < type -> V G 0 0 + * + * E is the exclusive marker that is not stored in swap entries. + * _PAGE_PRESENT (P), _PAGE_VALID (V) and_PAGE_GLOBAL (G) have to remain + * unused. + */ +#define __swp_type(x) (((x).val >> 4) & 0x1f) +#define __swp_offset(x) ((x).val >> 9) +#define __swp_entry(type, offset) ((swp_entry_t) { (((type) & 0x1f) << 4) | ((offset) << 9) }) +#define __pte_to_swp_entry(pte) ((swp_entry_t) { (pte).pte_high }) +#define __swp_entry_to_pte(x) ((pte_t) { 0, (x).val }) + +/* + * We borrow bit 57 (bit 25 in the low PTE) to store the exclusive marker in + * swap PTEs. + */ +#define _PAGE_SWP_EXCLUSIVE (1 << 25) + +#elif defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32) + +/* + * Format of swap PTEs: + * + * 6 6 6 6 5 5 5 5 5 5 5 5 5 5 4 4 4 4 4 4 4 4 4 4 3 3 3 3 3 3 3 3 + * 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 + * <------------------ zeroes -------------------> E P 0 0 0 0 0 0 + * + * 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 + * 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 + * <------------------- offset --------------------> < type -> V G + * + * E is the exclusive marker that is not stored in swap entries. + * _PAGE_PRESENT (P), _PAGE_VALID (V) and_PAGE_GLOBAL (G) have to remain + * unused. + */ +#define __swp_type(x) (((x).val >> 2) & 0x1f) +#define __swp_offset(x) ((x).val >> 7) +#define __swp_entry(type, offset) ((swp_entry_t) { (((type) & 0x1f) << 2) | ((offset) << 7) }) +#define __pte_to_swp_entry(pte) ((swp_entry_t) { (pte).pte_high }) +#define __swp_entry_to_pte(x) ((pte_t) { 0, (x).val }) + +/* + * We borrow bit 39 (bit 7 in the low PTE) to store the exclusive marker in swap + * PTEs. + */ +#define _PAGE_SWP_EXCLUSIVE (1 << 7) + +#else +/* + * Format of swap PTEs: + * + * 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 + * 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 + * <------------- offset --------------> < type -> 0 0 0 0 0 0 E P + * + * E is the exclusive marker that is not stored in swap entries. + * _PAGE_PRESENT (P), _PAGE_VALID (V) and_PAGE_GLOBAL (G) have to remain + * unused. The location of V and G varies. + */ +#define __swp_type(x) (((x).val >> 8) & 0x1f) +#define __swp_offset(x) ((x).val >> 13) +#define __swp_entry(type, offset) ((swp_entry_t) { ((type) << 8) | ((offset) << 13) }) +#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) }) +#define __swp_entry_to_pte(x) ((pte_t) { (x).val }) + +/* We borrow bit 1 to store the exclusive marker in swap PTEs. */ +#define _PAGE_SWP_EXCLUSIVE (1 << 1) + +#endif /* defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32) */ + +#endif /* defined(CONFIG_CPU_R3K_TLB) */ + +#endif /* _ASM_PGTABLE_32_H */ |