From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Wed, 5 Aug 2015 17:04:01 -0300 Subject: Initial import --- arch/avr32/include/asm/pgtable.h | 347 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 347 insertions(+) create mode 100644 arch/avr32/include/asm/pgtable.h (limited to 'arch/avr32/include/asm/pgtable.h') diff --git a/arch/avr32/include/asm/pgtable.h b/arch/avr32/include/asm/pgtable.h new file mode 100644 index 000000000..358006640 --- /dev/null +++ b/arch/avr32/include/asm/pgtable.h @@ -0,0 +1,347 @@ +/* + * Copyright (C) 2004-2006 Atmel Corporation + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#ifndef __ASM_AVR32_PGTABLE_H +#define __ASM_AVR32_PGTABLE_H + +#include + +#ifndef __ASSEMBLY__ +#include + +#endif /* !__ASSEMBLY__ */ + +/* + * Use two-level page tables just as the i386 (without PAE) + */ +#include + +/* + * The following code might need some cleanup when the values are + * final... + */ +#define PMD_SIZE (1UL << PMD_SHIFT) +#define PMD_MASK (~(PMD_SIZE-1)) +#define PGDIR_SIZE (1UL << PGDIR_SHIFT) +#define PGDIR_MASK (~(PGDIR_SIZE-1)) + +#define USER_PTRS_PER_PGD (TASK_SIZE / PGDIR_SIZE) +#define FIRST_USER_ADDRESS 0UL + +#ifndef __ASSEMBLY__ +extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; +extern void paging_init(void); + +/* + * ZERO_PAGE is a global shared page that is always zero: used for + * zero-mapped memory areas etc. + */ +extern struct page *empty_zero_page; +#define ZERO_PAGE(vaddr) (empty_zero_page) + +/* + * Just any arbitrary offset to the start of the vmalloc VM area: the + * current 8 MiB value just means that there will be a 8 MiB "hole" + * after the uncached physical memory (P2 segment) until the vmalloc + * area starts. That means that any out-of-bounds memory accesses will + * hopefully be caught; we don't know if the end of the P1/P2 segments + * are actually used for anything, but it is anyway safer to let the + * MMU catch these kinds of errors than to rely on the memory bus. + * + * A "hole" of the same size is added to the end of the P3 segment as + * well. It might seem wasteful to use 16 MiB of virtual address space + * on this, but we do have 512 MiB of it... + * + * The vmalloc() routines leave a hole of 4 KiB between each vmalloced + * area for the same reason. + */ +#define VMALLOC_OFFSET (8 * 1024 * 1024) +#define VMALLOC_START (P3SEG + VMALLOC_OFFSET) +#define VMALLOC_END (P4SEG - VMALLOC_OFFSET) +#endif /* !__ASSEMBLY__ */ + +/* + * Page flags. Some of these flags are not directly supported by + * hardware, so we have to emulate them. + */ +#define _TLBEHI_BIT_VALID 9 +#define _TLBEHI_VALID (1 << _TLBEHI_BIT_VALID) + +#define _PAGE_BIT_WT 0 /* W-bit : write-through */ +#define _PAGE_BIT_DIRTY 1 /* D-bit : page changed */ +#define _PAGE_BIT_SZ0 2 /* SZ0-bit : Size of page */ +#define _PAGE_BIT_SZ1 3 /* SZ1-bit : Size of page */ +#define _PAGE_BIT_EXECUTE 4 /* X-bit : execute access allowed */ +#define _PAGE_BIT_RW 5 /* AP0-bit : write access allowed */ +#define _PAGE_BIT_USER 6 /* AP1-bit : user space access allowed */ +#define _PAGE_BIT_BUFFER 7 /* B-bit : bufferable */ +#define _PAGE_BIT_GLOBAL 8 /* G-bit : global (ignore ASID) */ +#define _PAGE_BIT_CACHABLE 9 /* C-bit : cachable */ + +/* If we drop support for 1K pages, we get two extra bits */ +#define _PAGE_BIT_PRESENT 10 +#define _PAGE_BIT_ACCESSED 11 /* software: page was accessed */ + +#define _PAGE_WT (1 << _PAGE_BIT_WT) +#define _PAGE_DIRTY (1 << _PAGE_BIT_DIRTY) +#define _PAGE_EXECUTE (1 << _PAGE_BIT_EXECUTE) +#define _PAGE_RW (1 << _PAGE_BIT_RW) +#define _PAGE_USER (1 << _PAGE_BIT_USER) +#define _PAGE_BUFFER (1 << _PAGE_BIT_BUFFER) +#define _PAGE_GLOBAL (1 << _PAGE_BIT_GLOBAL) +#define _PAGE_CACHABLE (1 << _PAGE_BIT_CACHABLE) + +/* Software flags */ +#define _PAGE_ACCESSED (1 << _PAGE_BIT_ACCESSED) +#define _PAGE_PRESENT (1 << _PAGE_BIT_PRESENT) + +/* + * Page types, i.e. sizes. _PAGE_TYPE_NONE corresponds to what is + * usually called _PAGE_PROTNONE on other architectures. + * + * XXX: Find out if _PAGE_PROTNONE is equivalent with !_PAGE_USER. If + * so, we can encode all possible page sizes (although we can't really + * support 1K pages anyway due to the _PAGE_PRESENT and _PAGE_ACCESSED + * bits) + * + */ +#define _PAGE_TYPE_MASK ((1 << _PAGE_BIT_SZ0) | (1 << _PAGE_BIT_SZ1)) +#define _PAGE_TYPE_NONE (0 << _PAGE_BIT_SZ0) +#define _PAGE_TYPE_SMALL (1 << _PAGE_BIT_SZ0) +#define _PAGE_TYPE_MEDIUM (2 << _PAGE_BIT_SZ0) +#define _PAGE_TYPE_LARGE (3 << _PAGE_BIT_SZ0) + +/* + * Mask which drop software flags. We currently can't handle more than + * 512 MiB of physical memory, so we can use bits 29-31 for other + * stuff. With a fixed 4K page size, we can use bits 10-11 as well as + * bits 2-3 (SZ) + */ +#define _PAGE_FLAGS_HARDWARE_MASK 0xfffff3ff + +#define _PAGE_FLAGS_CACHE_MASK (_PAGE_CACHABLE | _PAGE_BUFFER | _PAGE_WT) + +/* Flags that may be modified by software */ +#define _PAGE_CHG_MASK (PTE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY \ + | _PAGE_FLAGS_CACHE_MASK) + +#define _PAGE_FLAGS_READ (_PAGE_CACHABLE | _PAGE_BUFFER) +#define _PAGE_FLAGS_WRITE (_PAGE_FLAGS_READ | _PAGE_RW | _PAGE_DIRTY) + +#define _PAGE_NORMAL(x) __pgprot((x) | _PAGE_PRESENT | _PAGE_TYPE_SMALL \ + | _PAGE_ACCESSED) + +#define PAGE_NONE (_PAGE_ACCESSED | _PAGE_TYPE_NONE) +#define PAGE_READ (_PAGE_FLAGS_READ | _PAGE_USER) +#define PAGE_EXEC (_PAGE_FLAGS_READ | _PAGE_EXECUTE | _PAGE_USER) +#define PAGE_WRITE (_PAGE_FLAGS_WRITE | _PAGE_USER) +#define PAGE_KERNEL _PAGE_NORMAL(_PAGE_FLAGS_WRITE | _PAGE_EXECUTE | _PAGE_GLOBAL) +#define PAGE_KERNEL_RO _PAGE_NORMAL(_PAGE_FLAGS_READ | _PAGE_EXECUTE | _PAGE_GLOBAL) + +#define _PAGE_P(x) _PAGE_NORMAL((x) & ~(_PAGE_RW | _PAGE_DIRTY)) +#define _PAGE_S(x) _PAGE_NORMAL(x) + +#define PAGE_COPY _PAGE_P(PAGE_WRITE | PAGE_READ) +#define PAGE_SHARED _PAGE_S(PAGE_WRITE | PAGE_READ) + +#ifndef __ASSEMBLY__ +/* + * The hardware supports flags for write- and execute access. Read is + * always allowed if the page is loaded into the TLB, so the "-w-", + * "--x" and "-wx" mappings are implemented as "rw-", "r-x" and "rwx", + * respectively. + * + * The "---" case is handled by software; the page will simply not be + * loaded into the TLB if the page type is _PAGE_TYPE_NONE. + */ + +#define __P000 __pgprot(PAGE_NONE) +#define __P001 _PAGE_P(PAGE_READ) +#define __P010 _PAGE_P(PAGE_WRITE) +#define __P011 _PAGE_P(PAGE_WRITE | PAGE_READ) +#define __P100 _PAGE_P(PAGE_EXEC) +#define __P101 _PAGE_P(PAGE_EXEC | PAGE_READ) +#define __P110 _PAGE_P(PAGE_EXEC | PAGE_WRITE) +#define __P111 _PAGE_P(PAGE_EXEC | PAGE_WRITE | PAGE_READ) + +#define __S000 __pgprot(PAGE_NONE) +#define __S001 _PAGE_S(PAGE_READ) +#define __S010 _PAGE_S(PAGE_WRITE) +#define __S011 _PAGE_S(PAGE_WRITE | PAGE_READ) +#define __S100 _PAGE_S(PAGE_EXEC) +#define __S101 _PAGE_S(PAGE_EXEC | PAGE_READ) +#define __S110 _PAGE_S(PAGE_EXEC | PAGE_WRITE) +#define __S111 _PAGE_S(PAGE_EXEC | PAGE_WRITE | PAGE_READ) + +#define pte_none(x) (!pte_val(x)) +#define pte_present(x) (pte_val(x) & _PAGE_PRESENT) + +#define pte_clear(mm,addr,xp) \ + do { \ + set_pte_at(mm, addr, xp, __pte(0)); \ + } while (0) + +/* + * The following only work if pte_present() is true. + * Undefined behaviour if not.. + */ +static inline int pte_write(pte_t pte) +{ + return pte_val(pte) & _PAGE_RW; +} +static inline int pte_dirty(pte_t pte) +{ + return pte_val(pte) & _PAGE_DIRTY; +} +static inline int pte_young(pte_t pte) +{ + return pte_val(pte) & _PAGE_ACCESSED; +} +static inline int pte_special(pte_t pte) +{ + return 0; +} + +/* Mutator functions for PTE bits */ +static inline pte_t pte_wrprotect(pte_t pte) +{ + set_pte(&pte, __pte(pte_val(pte) & ~_PAGE_RW)); + return pte; +} +static inline pte_t pte_mkclean(pte_t pte) +{ + set_pte(&pte, __pte(pte_val(pte) & ~_PAGE_DIRTY)); + return pte; +} +static inline pte_t pte_mkold(pte_t pte) +{ + set_pte(&pte, __pte(pte_val(pte) & ~_PAGE_ACCESSED)); + return pte; +} +static inline pte_t pte_mkwrite(pte_t pte) +{ + set_pte(&pte, __pte(pte_val(pte) | _PAGE_RW)); + return pte; +} +static inline pte_t pte_mkdirty(pte_t pte) +{ + set_pte(&pte, __pte(pte_val(pte) | _PAGE_DIRTY)); + return pte; +} +static inline pte_t pte_mkyoung(pte_t pte) +{ + set_pte(&pte, __pte(pte_val(pte) | _PAGE_ACCESSED)); + return pte; +} +static inline pte_t pte_mkspecial(pte_t pte) +{ + return pte; +} + +#define pmd_none(x) (!pmd_val(x)) +#define pmd_present(x) (pmd_val(x)) + +static inline void pmd_clear(pmd_t *pmdp) +{ + set_pmd(pmdp, __pmd(0)); +} + +#define pmd_bad(x) (pmd_val(x) & ~PAGE_MASK) + +/* + * Permanent address of a page. We don't support highmem, so this is + * trivial. + */ +#define pages_to_mb(x) ((x) >> (20-PAGE_SHIFT)) +#define pte_page(x) (pfn_to_page(pte_pfn(x))) + +/* + * Mark the prot value as uncacheable and unbufferable + */ +#define pgprot_noncached(prot) \ + __pgprot(pgprot_val(prot) & ~(_PAGE_BUFFER | _PAGE_CACHABLE)) + +/* + * Mark the prot value as uncacheable but bufferable + */ +#define pgprot_writecombine(prot) \ + __pgprot((pgprot_val(prot) & ~_PAGE_CACHABLE) | _PAGE_BUFFER) + +/* + * Conversion functions: convert a page and protection to a page entry, + * and a page entry and page directory to the page they refer to. + * + * extern pte_t mk_pte(struct page *page, pgprot_t pgprot) + */ +#define mk_pte(page, pgprot) pfn_pte(page_to_pfn(page), (pgprot)) + +static inline pte_t pte_modify(pte_t pte, pgprot_t newprot) +{ + set_pte(&pte, __pte((pte_val(pte) & _PAGE_CHG_MASK) + | pgprot_val(newprot))); + return pte; +} + +#define page_pte(page) page_pte_prot(page, __pgprot(0)) + +#define pmd_page_vaddr(pmd) pmd_val(pmd) +#define pmd_page(pmd) (virt_to_page(pmd_val(pmd))) + +/* to find an entry in a page-table-directory. */ +#define pgd_index(address) (((address) >> PGDIR_SHIFT) \ + & (PTRS_PER_PGD - 1)) +#define pgd_offset(mm, address) ((mm)->pgd + pgd_index(address)) + +/* to find an entry in a kernel page-table-directory */ +#define pgd_offset_k(address) pgd_offset(&init_mm, address) + +/* Find an entry in the third-level page table.. */ +#define pte_index(address) \ + ((address >> PAGE_SHIFT) & (PTRS_PER_PTE - 1)) +#define pte_offset(dir, address) \ + ((pte_t *) pmd_page_vaddr(*(dir)) + pte_index(address)) +#define pte_offset_kernel(dir, address) \ + ((pte_t *) pmd_page_vaddr(*(dir)) + pte_index(address)) +#define pte_offset_map(dir, address) pte_offset_kernel(dir, address) +#define pte_unmap(pte) do { } while (0) + +struct vm_area_struct; +extern void update_mmu_cache(struct vm_area_struct * vma, + unsigned long address, pte_t *ptep); + +/* + * Encode and decode a swap entry + * + * Constraints: + * _PAGE_TYPE_* at bits 2-3 (for emulating _PAGE_PROTNONE) + * _PAGE_PRESENT at bit 10 + * + * We encode the type into bits 4-9 and offset into bits 11-31. This + * gives us a 21 bits offset, or 2**21 * 4K = 8G usable swap space per + * device, and 64 possible types. + * + * NOTE: We should set ZEROs at the position of _PAGE_PRESENT + * and _PAGE_PROTNONE bits + */ +#define __swp_type(x) (((x).val >> 4) & 0x3f) +#define __swp_offset(x) ((x).val >> 11) +#define __swp_entry(type, offset) ((swp_entry_t) { ((type) << 4) | ((offset) << 11) }) +#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) }) +#define __swp_entry_to_pte(x) ((pte_t) { (x).val }) + +typedef pte_t *pte_addr_t; + +#define kern_addr_valid(addr) (1) + +/* No page table caches to initialize (?) */ +#define pgtable_cache_init() do { } while(0) + +#include + +#endif /* !__ASSEMBLY__ */ + +#endif /* __ASM_AVR32_PGTABLE_H */ -- cgit v1.2.3-54-g00ecf