include/asm-xtensa/page.h.n

   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 #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 /*
  39  * These are used to make use of C type-checking..
  40  */
  41 typedef struct { unsigned long pte; } pte_t;            /* page table entry */
  42 typedef struct { unsigned long pmd; } pmd_t;            /* PMD 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 pmd_val(x)      ((x).pmd)
  48 #define pgd_val(x)      ((x).pgd)
  49 #define pgprot_val(x)   ((x).pgprot)
  50
  51 #define __pte(x)        ((pte_t) { (x) } )
  52 #define __pmd(x)        ((pmd_t) { (x) } )
  53 #define __pgd(x)        ((pgd_t) { (x) } )
  54 #define __pgprot(x)     ((pgprot_t) { (x) } )
  55
  56 /*
  57  * Pure 2^n version of get_order
  58  */
  59 extern __inline__ int get_order(unsigned long size)
  60 {
  61         int order;
  62 #ifndef XCHAL_HAVE_NSU
  63         unsigned long x1, x2, x4, x8, x16;
  64
  65         size = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
  66         x1  = size & 0xAAAAAAAA;
  67         x2  = size & 0xCCCCCCCC;
  68         x4  = size & 0xF0F0F0F0;
  69         x8  = size & 0xFF00FF00;
  70         x16 = size & 0xFFFF0000;
  71         order = x2 ? 2 : 0;
  72         order += (x16 != 0) * 16;
  73         order += (x8 != 0) * 8;
  74         order += (x4 != 0) * 4;
  75         order += (x1 != 0);
  76
  77         return order;
  78 #else
  79         size = (size - 1) >> PAGE_SHIFT;
  80         asm ("nsau %0, %1" : "=r" (order) : "r" (size));
  81         return 32 - order;
  82 #endif
  83 }
  84
  85
  86 struct page;
  87 extern void clear_page(void *page);
  88 extern void copy_page(void *to, void *from);
  89
  90 /*
  91  * If we have cache aliasing and writeback caches, we might have to do
  92  * some extra work
  93  */
  94
  95 #if (DCACHE_WAY_SIZE > PAGE_SIZE) && XCHAL_DCACHE_IS_WRITEBACK
  96 void clear_user_page(void *addr, unsigned long vaddr, struct page* page);
  97 void copy_user_page(void *to, void* from, unsigned long vaddr, struct page* page);
  98 #else
  99 # define clear_user_page(page,vaddr,pg)         clear_page(page)
 100 # define copy_user_page(to, from, vaddr, pg)    copy_page(to, from)
 101 #endif
 102
 103
 104 /*
 105  * This handles the memory map.  We handle pages at
 106  * XCHAL_KSEG_CACHED_VADDR for kernels with 32 bit address space.
 107  * These macros are for conversion of kernel address, not user
 108  * addresses.
 109  */
 110
 111 #define __pa(x)                 ((unsigned long) (x) - PAGE_OFFSET)
 112 #define __va(x)                 ((void *)((unsigned long) (x) + PAGE_OFFSET))
 113 #define pfn_valid(pfn)          ((unsigned long)pfn < max_mapnr)
 114 #ifndef CONFIG_DISCONTIGMEM
 115 # define pfn_to_page(pfn)       (mem_map + (pfn))
 116 # define page_to_pfn(page)      ((unsigned long)((page) - mem_map))
 117 #else
 118 # error CONFIG_DISCONTIGMEM not supported
 119 #endif
 120
 121 #define virt_to_page(kaddr)     pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
 122 #define page_to_virt(page)      __va(page_to_pfn(page) << PAGE_SHIFT)
 123 #define virt_addr_valid(kaddr)  pfn_valid(__pa(kaddr) >> PAGE_SHIFT)
 124 #define page_to_phys(page)      (page_to_pfn(page) << PAGE_SHIFT)
 125
 126 #define WANT_PAGE_VIRTUAL
 127
 128
 129 #endif /* __ASSEMBLY__ */
 130
 131 #define VM_DATA_DEFAULT_FLAGS   (VM_READ | VM_WRITE | VM_EXEC | \
 132                                  VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
 133
 134 #endif /* __KERNEL__ */
 135 #endif /* _XTENSA_PAGE_H */