include/asm-xtensa/page.h

   1 /*
   2  * linux/include/asm-xtensa/page.h
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version2 as
   6  * published by the Free Software Foundation.
   7  *
   8  * Copyright (C) 2001 - 2005 Tensilica Inc.
   9  */
  10
  11 #ifndef _XTENSA_PAGE_H
  12 #define _XTENSA_PAGE_H
  13
  14 #ifdef __KERNEL__
  15
  16 #include <asm/processor.h>
  17 #include <linux/config.h>
  18
  19 /*
  20  * PAGE_SHIFT determines the page size
  21  * PAGE_ALIGN(x) aligns the pointer to the (next) page boundary
  22  */
  23
  24 #define PAGE_SHIFT              XCHAL_MMU_MIN_PTE_PAGE_SIZE
  25 #define PAGE_SIZE               (1 << PAGE_SHIFT)
  26 #define PAGE_MASK               (~(PAGE_SIZE-1))
  27 #define PAGE_ALIGN(addr)        (((addr)+PAGE_SIZE - 1) & PAGE_MASK)
  28
  29 #define DCACHE_WAY_SIZE         (XCHAL_DCACHE_SIZE / XCHAL_DCACHE_WAYS)
  30 #define PAGE_OFFSET             XCHAL_KSEG_CACHED_VADDR
  31
  32 #ifdef __ASSEMBLY__
  33
  34 #define __pgprot(x)     (x)
  35
  36 #else
  37
  38 /*
  39  * These are used to make use of C type-checking..
  40  */
  41
  42 typedef struct { unsigned long pte; } pte_t;            /* page table entry */
  43 typedef struct { unsigned long pgd; } pgd_t;            /* PGD table entry */
  44 typedef struct { unsigned long pgprot; } pgprot_t;
  45
  46 #define pte_val(x)      ((x).pte)
  47 #define pgd_val(x)      ((x).pgd)
  48 #define pgprot_val(x)   ((x).pgprot)
  49
  50 #define __pte(x)        ((pte_t) { (x) } )
  51 #define __pgd(x)        ((pgd_t) { (x) } )
  52 #define __pgprot(x)     ((pgprot_t) { (x) } )
  53
  54 /*
  55  * Pure 2^n version of get_order
  56  */
  57
  58 static inline int get_order(unsigned long size)
  59 {
  60         int order;
  61 #ifndef XCHAL_HAVE_NSU
  62         unsigned long x1, x2, x4, x8, x16;
  63
  64         size = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
  65         x1  = size & 0xAAAAAAAA;
  66         x2  = size & 0xCCCCCCCC;
  67         x4  = size & 0xF0F0F0F0;
  68         x8  = size & 0xFF00FF00;
  69         x16 = size & 0xFFFF0000;
  70         order = x2 ? 2 : 0;
  71         order += (x16 != 0) * 16;
  72         order += (x8 != 0) * 8;
  73         order += (x4 != 0) * 4;
  74         order += (x1 != 0);
  75
  76         return order;
  77 #else
  78         size = (size - 1) >> PAGE_SHIFT;
  79         asm ("nsau %0, %1" : "=r" (order) : "r" (size));
  80         return 32 - order;
  81 #endif
  82 }
  83
  84
  85 struct page;
  86 extern void clear_page(void *page);
  87 extern void copy_page(void *to, void *from);
  88
  89 /*
  90  * If we have cache aliasing and writeback caches, we might have to do
  91  * some extra work
  92  */
  93
  94 #if (DCACHE_WAY_SIZE > PAGE_SIZE)
  95 void clear_user_page(void *addr, unsigned long vaddr, struct page* page);
  96 void copy_user_page(void *to,void* from,unsigned long vaddr,struct page* page);
  97 #else
  98 # define clear_user_page(page,vaddr,pg)         clear_page(page)
  99 # define copy_user_page(to, from, vaddr, pg)    copy_page(to, from)
 100 #endif
 101
 102 /*
 103  * This handles the memory map.  We handle pages at
 104  * XCHAL_KSEG_CACHED_VADDR for kernels with 32 bit address space.
 105  * These macros are for conversion of kernel address, not user
 106  * addresses.
 107  */
 108
 109 #define __pa(x)                 ((unsigned long) (x) - PAGE_OFFSET)
 110 #define __va(x)                 ((void *)((unsigned long) (x) + PAGE_OFFSET))
 111 #define pfn_valid(pfn)          ((unsigned long)pfn < max_mapnr)
 112 #ifndef CONFIG_DISCONTIGMEM
 113 # define pfn_to_page(pfn)       (mem_map + (pfn))
 114 # define page_to_pfn(page)      ((unsigned long)((page) - mem_map))
 115 #else
 116 # error CONFIG_DISCONTIGMEM not supported
 117 #endif
 118
 119 #define virt_to_page(kaddr)     pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
 120 #define page_to_virt(page)      __va(page_to_pfn(page) << PAGE_SHIFT)
 121 #define virt_addr_valid(kaddr)  pfn_valid(__pa(kaddr) >> PAGE_SHIFT)
 122 #define page_to_phys(page)      (page_to_pfn(page) << PAGE_SHIFT)
 123
 124 #define WANT_PAGE_VIRTUAL
 125
 126
 127 #endif /* __ASSEMBLY__ */
 128
 129 #define VM_DATA_DEFAULT_FLAGS   (VM_READ | VM_WRITE | VM_EXEC | \
 130                                  VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
 131
 132 #endif /* __KERNEL__ */
 133 #endif /* _XTENSA_PAGE_H */