/* * linux/arch/unicore32/include/asm/pgtable.h * * Code specific to PKUnity SoC and UniCore ISA * * Copyright (C) 2001-2010 GUAN Xue-tao * * 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 __UNICORE_PGTABLE_H__ #define __UNICORE_PGTABLE_H__ #include #include #include #include /* * Just any arbitrary offset to the start of the vmalloc VM area: the * current 8MB value just means that there will be a 8MB "hole" after the * physical memory until the kernel virtual memory starts. That means that * any out-of-bounds memory accesses will hopefully be caught. * The vmalloc() routines leaves a hole of 4kB between each vmalloced * area for the same reason. ;) * * Note that platforms may override VMALLOC_START, but they must provide * VMALLOC_END. VMALLOC_END defines the (exclusive) limit of this space, * which may not overlap IO space. */ #ifndef VMALLOC_START #define VMALLOC_OFFSET SZ_8M #define VMALLOC_START (((unsigned long)high_memory + VMALLOC_OFFSET) \ & ~(VMALLOC_OFFSET-1)) #define VMALLOC_END (0xff000000UL) #endif #define PTRS_PER_PTE 1024 #define PTRS_PER_PGD 1024 /* * PGDIR_SHIFT determines what a third-level page table entry can map */ #define PGDIR_SHIFT 22 #ifndef __ASSEMBLY__ extern void __pte_error(const char *file, int line, unsigned long val); extern void __pgd_error(const char *file, int line, unsigned long val); #define pte_ERROR(pte) __pte_error(__FILE__, __LINE__, pte_val(pte)) #define pgd_ERROR(pgd) __pgd_error(__FILE__, __LINE__, pgd_val(pgd)) #endif /* !__ASSEMBLY__ */ #define PGDIR_SIZE (1UL << PGDIR_SHIFT) #define PGDIR_MASK (~(PGDIR_SIZE-1)) /* * This is the lowest virtual address we can permit any user space * mapping to be mapped at. This is particularly important for * non-high vector CPUs. */ #define FIRST_USER_ADDRESS PAGE_SIZE #define FIRST_USER_PGD_NR 1 #define USER_PTRS_PER_PGD ((TASK_SIZE/PGDIR_SIZE) - FIRST_USER_PGD_NR) /* * section address mask and size definitions. */ #define SECTION_SHIFT 22 #define SECTION_SIZE (1UL << SECTION_SHIFT) #define SECTION_MASK (~(SECTION_SIZE-1)) #ifndef __ASSEMBLY__ /* * The pgprot_* and protection_map entries will be fixed up in runtime * to include the cachable bits based on memory policy, as well as any * architecture dependent bits. */ #define _PTE_DEFAULT (PTE_PRESENT | PTE_YOUNG | PTE_CACHEABLE) extern pgprot_t pgprot_user; extern pgprot_t pgprot_kernel; #define PAGE_NONE pgprot_user #define PAGE_SHARED __pgprot(pgprot_val(pgprot_user | PTE_READ \ | PTE_WRITE) #define PAGE_SHARED_EXEC __pgprot(pgprot_val(pgprot_user | PTE_READ \ | PTE_WRITE \ | PTE_EXEC) #define PAGE_COPY __pgprot(pgprot_val(pgprot_user | PTE_READ) #define PAGE_COPY_EXEC __pgprot(pgprot_val(pgprot_user | PTE_READ \ | PTE_EXEC) #define PAGE_READONLY __pgprot(pgprot_val(pgprot_user | PTE_READ) #define PAGE_READONLY_EXEC __pgprot(pgprot_val(pgprot_user | PTE_READ \ | PTE_EXEC) #define PAGE_KERNEL pgprot_kernel #define PAGE_KERNEL_EXEC __pgprot(pgprot_val(pgprot_kernel | PTE_EXEC)) #define __PAGE_NONE __pgprot(_PTE_DEFAULT) #define __PAGE_SHARED __pgprot(_PTE_DEFAULT | PTE_READ \ | PTE_WRITE) #define __PAGE_SHARED_EXEC __pgprot(_PTE_DEFAULT | PTE_READ \ | PTE_WRITE \ | PTE_EXEC) #define __PAGE_COPY __pgprot(_PTE_DEFAULT | PTE_READ) #define __PAGE_COPY_EXEC __pgprot(_PTE_DEFAULT | PTE_READ \ | PTE_EXEC) #define __PAGE_READONLY __pgprot(_PTE_DEFAULT | PTE_READ) #define __PAGE_READONLY_EXEC __pgprot(_PTE_DEFAULT | PTE_READ \ | PTE_EXEC) #endif /* __ASSEMBLY__ */ /* * The table below defines the page protection levels that we insert into our * Linux page table version. These get translated into the best that the * architecture can perform. Note that on UniCore hardware: * 1) We cannot do execute protection * 2) If we could do execute protection, then read is implied * 3) write implies read permissions */ #define __P000 __PAGE_NONE #define __P001 __PAGE_READONLY #define __P010 __PAGE_COPY #define __P011 __PAGE_COPY #define __P100 __PAGE_READONLY_EXEC #define __P101 __PAGE_READONLY_EXEC #define __P110 __PAGE_COPY_EXEC #define __P111 __PAGE_COPY_EXEC #define __S000 __PAGE_NONE #define __S001 __PAGE_READONLY #define __S010 __PAGE_SHARED #define __S011 __PAGE_SHARED #define __S100 __PAGE_READONLY_EXEC #define __S101 __PAGE_READONLY_EXEC #define __S110 __PAGE_SHARED_EXEC #define __S111 __PAGE_SHARED_EXEC #ifndef __ASSEMBLY__ /* * 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) #define pte_pfn(pte) (pte_val(pte) >> PAGE_SHIFT) #define pfn_pte(pfn, prot) (__pte(((pfn) << PAGE_SHIFT) \ | pgprot_val(prot))) #define pte_none(pte) (!pte_val(pte)) #define pte_clear(mm, addr, ptep) set_pte(ptep, __pte(0)) #define pte_page(pte) (pfn_to_page(pte_pfn(pte))) #define pte_offset_kernel(dir, addr) (pmd_page_vaddr(*(dir)) \ + __pte_index(addr)) #define pte_offset_map(dir, addr) (pmd_page_vaddr(*(dir)) \ + __pte_index(addr)) #define pte_unmap(pte) do { } while (0) #define set_pte(ptep, pte) cpu_set_pte(ptep, pte) #define set_pte_at(mm, addr, ptep, pteval) \ do { \ set_pte(ptep, pteval); \ } while (0) /* * The following only work if pte_present() is true. * Undefined behaviour if not.. */ #define pte_present(pte) (pte_val(pte) & PTE_PRESENT) #define pte_write(pte) (pte_val(pte) & PTE_WRITE) #define pte_dirty(pte) (pte_val(pte) & PTE_DIRTY) #define pte_young(pte) (pte_val(pte) & PTE_YOUNG) #define pte_exec(pte) (pte_val(pte) & PTE_EXEC) #define pte_special(pte) (0) #define PTE_BIT_FUNC(fn, op) \ static inline pte_t pte_##fn(pte_t pte) { pte_val(pte) op; return pte; } PTE_BIT_FUNC(wrprotect, &= ~PTE_WRITE); PTE_BIT_FUNC(mkwrite, |= PTE_WRITE); PTE_BIT_FUNC(mkclean, &= ~PTE_DIRTY); PTE_BIT_FUNC(mkdirty, |= PTE_DIRTY); PTE_BIT_FUNC(mkold, &= ~PTE_YOUNG); PTE_BIT_FUNC(mkyoung, |= PTE_YOUNG); static inline pte_t pte_mkspecial(pte_t pte) { return pte; } /* * Mark the prot value as uncacheable. */ #define pgprot_noncached(prot) \ __pgprot(pgprot_val(prot) & ~PTE_CACHEABLE) #define pgprot_writecombine(prot) \ __pgprot(pgprot_val(prot) & ~PTE_CACHEABLE) #define pgprot_dmacoherent(prot) \ __pgprot(pgprot_val(prot) & ~PTE_CACHEABLE) #define pmd_none(pmd) (!pmd_val(pmd)) #define pmd_present(pmd) (pmd_val(pmd) & PMD_PRESENT) #define pmd_bad(pmd) (((pmd_val(pmd) & \ (PMD_PRESENT | PMD_TYPE_MASK)) \ != (PMD_PRESENT | PMD_TYPE_TABLE))) #define set_pmd(pmdpd, pmdval) \ do { \ *(pmdpd) = pmdval; \ } while (0) #define pmd_clear(pmdp) \ do { \ set_pmd(pmdp, __pmd(0));\ clean_pmd_entry(pmdp); \ } while (0) #define pmd_page_vaddr(pmd) ((pte_t *)__va(pmd_val(pmd) & PAGE_MASK)) #define pmd_page(pmd) pfn_to_page(__phys_to_pfn(pmd_val(pmd))) /* * Conversion functions: convert a page and protection to a page entry, * and a page entry and page directory to the page they refer to. */ #define mk_pte(page, prot) pfn_pte(page_to_pfn(page), prot) /* to find an entry in a page-table-directory */ #define pgd_index(addr) ((addr) >> PGDIR_SHIFT) #define pgd_offset(mm, addr) ((mm)->pgd+pgd_index(addr)) /* to find an entry in a kernel page-table-directory */ #define pgd_offset_k(addr) pgd_offset(&init_mm, addr) /* Find an entry in the third-level page table.. */ #define __pte_index(addr) (((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1)) static inline pte_t pte_modify(pte_t pte, pgprot_t newprot) { const unsigned long mask = PTE_EXEC | PTE_WRITE | PTE_READ; pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask); return pte; } extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; /* * Encode and decode a swap entry. Swap entries are stored in the Linux * page tables as follows: * * 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 * * This gives us up to 127 swap files and 32GB per swap file. Note that * the offset field is always non-zero. */ #define __SWP_TYPE_SHIFT 5 #define __SWP_TYPE_BITS 7 #define __SWP_TYPE_MASK ((1 << __SWP_TYPE_BITS) - 1) #define __SWP_OFFSET_SHIFT (__SWP_TYPE_BITS + __SWP_TYPE_SHIFT) #define __swp_type(x) (((x).val >> __SWP_TYPE_SHIFT) \ & __SWP_TYPE_MASK) #define __swp_offset(x) ((x).val >> __SWP_OFFSET_SHIFT) #define __swp_entry(type, offset) ((swp_entry_t) { \ ((type) << __SWP_TYPE_SHIFT) | \ ((offset) << __SWP_OFFSET_SHIFT) }) #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) }) #define __swp_entry_to_pte(swp) ((pte_t) { (swp).val }) /* * It is an error for the kernel to have more swap files than we can * encode in the PTEs. This ensures that we know when MAX_SWAPFILES * is increased beyond what we presently support. */ #define MAX_SWAPFILES_CHECK() \ BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > __SWP_TYPE_BITS) /* * Encode and decode a file entry. File entries are stored in the Linux * page tables as follows: * * 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 ----------------------> 1 0 0 0 */ #define pte_file(pte) (pte_val(pte) & PTE_FILE) #define pte_to_pgoff(x) (pte_val(x) >> 4) #define pgoff_to_pte(x) __pte(((x) << 4) | PTE_FILE) #define PTE_FILE_MAX_BITS 28 /* Needs to be defined here and not in linux/mm.h, as it is arch dependent */ /* FIXME: this is not correct */ #define kern_addr_valid(addr) (1) #include /* * remap a physical page `pfn' of size `size' with page protection `prot' * into virtual address `from' */ #define io_remap_pfn_range(vma, from, pfn, size, prot) \ remap_pfn_range(vma, from, pfn, size, prot) #define pgtable_cache_init() do { } while (0) #endif /* !__ASSEMBLY__ */ #endif /* __UNICORE_PGTABLE_H__ */