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 #define XCHAL_KSEG_CACHED_VADDR 0xd0000000
  19 #define XCHAL_KSEG_BYPASS_VADDR 0xd8000000
  20 #define XCHAL_KSEG_PADDR        0x00000000
  21 #define XCHAL_KSEG_SIZE         0x08000000
  22
  23 /*
  24  * PAGE_SHIFT determines the page size
  25  * PAGE_ALIGN(x) aligns the pointer to the (next) page boundary
  26  */
  27
  28 #define PAGE_SHIFT              12
  29 #define PAGE_SIZE               (1 << PAGE_SHIFT)
  30 #define PAGE_MASK               (~(PAGE_SIZE-1))
  31 #define PAGE_ALIGN(addr)        (((addr)+PAGE_SIZE - 1) & PAGE_MASK)
  32
  33 #define PAGE_OFFSET             XCHAL_KSEG_CACHED_VADDR
  34 #define MAX_MEM_PFN             XCHAL_KSEG_SIZE
  35 #define PGTABLE_START           0x80000000
  36
  37 #ifdef __ASSEMBLY__
  38
  39 #define __pgprot(x)     (x)
  40
  41 #else
  42
  43 /*
  44  * These are used to make use of C type-checking..
  45  */
  46
  47 typedef struct { unsigned long pte; } pte_t;            /* page table entry */
  48 typedef struct { unsigned long pgd; } pgd_t;            /* PGD table entry */
  49 typedef struct { unsigned long pgprot; } pgprot_t;
  50
  51 #define pte_val(x)      ((x).pte)
  52 #define pgd_val(x)      ((x).pgd)
  53 #define pgprot_val(x)   ((x).pgprot)
  54
  55 #define __pte(x)        ((pte_t) { (x) } )
  56 #define __pgd(x)        ((pgd_t) { (x) } )
  57 #define __pgprot(x)     ((pgprot_t) { (x) } )
  58
  59 /*
  60  * Pure 2^n version of get_order
  61  */
  62
  63 static inline int get_order(unsigned long size)
  64 {
  65         int order;
  66 #ifndef XCHAL_HAVE_NSU
  67         unsigned long x1, x2, x4, x8, x16;
  68
  69         size = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
  70         x1  = size & 0xAAAAAAAA;
  71         x2  = size & 0xCCCCCCCC;
  72         x4  = size & 0xF0F0F0F0;
  73         x8  = size & 0xFF00FF00;
  74         x16 = size & 0xFFFF0000;
  75         order = x2 ? 2 : 0;
  76         order += (x16 != 0) * 16;
  77         order += (x8 != 0) * 8;
  78         order += (x4 != 0) * 4;
  79         order += (x1 != 0);
  80
  81         return order;
  82 #else
  83         size = (size - 1) >> PAGE_SHIFT;
  84         asm ("nsau %0, %1" : "=r" (order) : "r" (size));
  85         return 32 - order;
  86 #endif
  87 }
  88
  89
  90 struct page;
  91 extern void clear_page(void *page);
  92 extern void copy_page(void *to, void *from);
  93
  94 /*
  95  * If we have cache aliasing and writeback caches, we might have to do
  96  * some extra work
  97  */
  98
  99 #if (DCACHE_WAY_SIZE > PAGE_SIZE)
 100 void clear_user_page(void *addr, unsigned long vaddr, struct page* page);
 101 void copy_user_page(void *to,void* from,unsigned long vaddr,struct page* page);
 102 #else
 103 # define clear_user_page(page,vaddr,pg)         clear_page(page)
 104 # define copy_user_page(to, from, vaddr, pg)    copy_page(to, from)
 105 #endif
 106
 107 /*
 108  * This handles the memory map.  We handle pages at
 109  * XCHAL_KSEG_CACHED_VADDR for kernels with 32 bit address space.
 110  * These macros are for conversion of kernel address, not user
 111  * addresses.
 112  */
 113
 114 #define __pa(x)                 ((unsigned long) (x) - PAGE_OFFSET)
 115 #define __va(x)                 ((void *)((unsigned long) (x) + PAGE_OFFSET))
 116 #define pfn_valid(pfn)          ((unsigned long)pfn < max_mapnr)
 117 #ifdef CONFIG_DISCONTIGMEM
 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 #include <asm-generic/memory_model.h>
 135 #endif /* __KERNEL__ */
 136 #endif /* _XTENSA_PAGE_H */