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