arch/hexagon/include/asm/page.h

   1 /*
   2  * Page management definitions for the Hexagon architecture
   3  *
   4  * Copyright (c) 2010-2013, The Linux Foundation. All rights reserved.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 and
   8  * only version 2 as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  18  * 02110-1301, USA.
  19  */
  20
  21 #ifndef _ASM_PAGE_H
  22 #define _ASM_PAGE_H
  23
  24 #include <linux/const.h>
  25
  26 /*  This is probably not the most graceful way to handle this.  */
  27
  28 #ifdef CONFIG_PAGE_SIZE_4KB
  29 #define PAGE_SHIFT 12
  30 #define HEXAGON_L1_PTE_SIZE __HVM_PDE_S_4KB
  31 #endif
  32
  33 #ifdef CONFIG_PAGE_SIZE_16KB
  34 #define PAGE_SHIFT 14
  35 #define HEXAGON_L1_PTE_SIZE __HVM_PDE_S_16KB
  36 #endif
  37
  38 #ifdef CONFIG_PAGE_SIZE_64KB
  39 #define PAGE_SHIFT 16
  40 #define HEXAGON_L1_PTE_SIZE __HVM_PDE_S_64KB
  41 #endif
  42
  43 #ifdef CONFIG_PAGE_SIZE_256KB
  44 #define PAGE_SHIFT 18
  45 #define HEXAGON_L1_PTE_SIZE __HVM_PDE_S_256KB
  46 #endif
  47
  48 #ifdef CONFIG_PAGE_SIZE_1MB
  49 #define PAGE_SHIFT 20
  50 #define HEXAGON_L1_PTE_SIZE __HVM_PDE_S_1MB
  51 #endif
  52
  53 /*
  54  *  These should be defined in hugetlb.h, but apparently not.
  55  *  "Huge" for us should be 4MB or 16MB, which are both represented
  56  *  in L1 PTE's.  Right now, it's set up for 4MB.
  57  */
  58 #ifdef CONFIG_HUGETLB_PAGE
  59 #define HPAGE_SHIFT 22
  60 #define HPAGE_SIZE (1UL << HPAGE_SHIFT)
  61 #define HPAGE_MASK (~(HPAGE_SIZE-1))
  62 #define HUGETLB_PAGE_ORDER (HPAGE_SHIFT-PAGE_SHIFT)
  63 #define HVM_HUGEPAGE_SIZE 0x5
  64 #endif
  65
  66 #define PAGE_SIZE  (1UL << PAGE_SHIFT)
  67 #define PAGE_MASK  (~((1 << PAGE_SHIFT) - 1))
  68
  69 #ifdef __KERNEL__
  70 #ifndef __ASSEMBLY__
  71
  72 /*
  73  * This is for PFN_DOWN, which mm.h needs.  Seems the right place to pull it in.
  74  */
  75 #include <linux/pfn.h>
  76
  77 /*
  78  * We implement a two-level architecture-specific page table structure.
  79  * Null intermediate page table level (pmd, pud) definitions will come from
  80  * asm-generic/pagetable-nopmd.h and asm-generic/pagetable-nopud.h
  81  */
  82 typedef struct { unsigned long pte; } pte_t;
  83 typedef struct { unsigned long pgd; } pgd_t;
  84 typedef struct { unsigned long pgprot; } pgprot_t;
  85 typedef struct page *pgtable_t;
  86
  87 #define pte_val(x)     ((x).pte)
  88 #define pgd_val(x)     ((x).pgd)
  89 #define pgprot_val(x)  ((x).pgprot)
  90 #define __pte(x)       ((pte_t) { (x) })
  91 #define __pgd(x)       ((pgd_t) { (x) })
  92 #define __pgprot(x)    ((pgprot_t) { (x) })
  93
  94 /*
  95  * We need a __pa and a __va routine for kernel space.
  96  * MIPS says they're only used during mem_init.
  97  * also, check if we need a PHYS_OFFSET.
  98  */
  99 #define __pa(x) ((unsigned long)(x) - PAGE_OFFSET + PHYS_OFFSET)
 100 #define __va(x) ((void *)((unsigned long)(x) - PHYS_OFFSET + PAGE_OFFSET))
 101
 102 /* The "page frame" descriptor is defined in linux/mm.h */
 103 struct page;
 104
 105 /* Returns page frame descriptor for virtual address. */
 106 #define virt_to_page(kaddr) pfn_to_page(PFN_DOWN(__pa(kaddr)))
 107
 108 /* Default vm area behavior is non-executable.  */
 109 #define VM_DATA_DEFAULT_FLAGS (VM_READ | VM_WRITE | \
 110                                 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
 111
 112 #define pfn_valid(pfn) ((pfn) < max_mapnr)
 113 #define virt_addr_valid(kaddr) pfn_valid(__pa(kaddr) >> PAGE_SHIFT)
 114
 115 /*  Need to not use a define for linesize; may move this to another file.  */
 116 static inline void clear_page(void *page)
 117 {
 118         /*  This can only be done on pages with L1 WB cache */
 119         asm volatile(
 120                 "       loop0(1f,%1);\n"
 121                 "1:     { dczeroa(%0);\n"
 122                 "         %0 = add(%0,#32); }:endloop0\n"
 123                 : "+r" (page)
 124                 : "r" (PAGE_SIZE/32)
 125                 : "lc0", "sa0", "memory"
 126         );
 127 }
 128
 129 #define copy_page(to, from)     memcpy((to), (from), PAGE_SIZE)
 130
 131 /*
 132  * Under assumption that kernel always "sees" user map...
 133  */
 134 #define clear_user_page(page, vaddr, pg)        clear_page(page)
 135 #define copy_user_page(to, from, vaddr, pg)     copy_page(to, from)
 136
 137 /*
 138  * page_to_phys - convert page to physical address
 139  * @page - pointer to page entry in mem_map
 140  */
 141 #define page_to_phys(page)      (page_to_pfn(page) << PAGE_SHIFT)
 142
 143 #define virt_to_pfn(kaddr)      (__pa(kaddr) >> PAGE_SHIFT)
 144 #define pfn_to_virt(pfn)        __va((pfn) << PAGE_SHIFT)
 145
 146 #define page_to_virt(page)      __va(page_to_phys(page))
 147
 148 /*
 149  * For port to Hexagon Virtual Machine, MAYBE we check for attempts
 150  * to reference reserved HVM space, but in any case, the VM will be
 151  * protected.
 152  */
 153 #define kern_addr_valid(addr)   (1)
 154
 155 #include <asm/mem-layout.h>
 156 #include <asm-generic/memory_model.h>
 157 /* XXX Todo: implement assembly-optimized version of getorder. */
 158 #include <asm-generic/getorder.h>
 159
 160 #endif /* ifdef __ASSEMBLY__ */
 161 #endif /* ifdef __KERNEL__ */
 162
 163 #endif