arch/tile/include/asm/page.h

   1 /*
   2  * Copyright 2010 Tilera Corporation. All Rights Reserved.
   3  *
   4  *   This program is free software; you can redistribute it and/or
   5  *   modify it under the terms of the GNU General Public License
   6  *   as published by the Free Software Foundation, version 2.
   7  *
   8  *   This program is distributed in the hope that it will be useful, but
   9  *   WITHOUT ANY WARRANTY; without even the implied warranty of
  10  *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
  11  *   NON INFRINGEMENT.  See the GNU General Public License for
  12  *   more details.
  13  */
  14
  15 #ifndef _ASM_TILE_PAGE_H
  16 #define _ASM_TILE_PAGE_H
  17
  18 #include <linux/const.h>
  19 #include <hv/hypervisor.h>
  20 #include <arch/chip.h>
  21
  22 /* PAGE_SHIFT and HPAGE_SHIFT determine the page sizes. */
  23 #if defined(CONFIG_PAGE_SIZE_16KB)
  24 #define PAGE_SHIFT      14
  25 #define CTX_PAGE_FLAG   HV_CTX_PG_SM_16K
  26 #elif defined(CONFIG_PAGE_SIZE_64KB)
  27 #define PAGE_SHIFT      16
  28 #define CTX_PAGE_FLAG   HV_CTX_PG_SM_64K
  29 #else
  30 #define PAGE_SHIFT      HV_LOG2_DEFAULT_PAGE_SIZE_SMALL
  31 #define CTX_PAGE_FLAG   0
  32 #endif
  33 #define HPAGE_SHIFT     HV_LOG2_DEFAULT_PAGE_SIZE_LARGE
  34
  35 #define PAGE_SIZE       (_AC(1, UL) << PAGE_SHIFT)
  36 #define HPAGE_SIZE      (_AC(1, UL) << HPAGE_SHIFT)
  37
  38 #define PAGE_MASK       (~(PAGE_SIZE - 1))
  39 #define HPAGE_MASK      (~(HPAGE_SIZE - 1))
  40
  41 /*
  42  * We do define AT_SYSINFO_EHDR to support vDSO,
  43  * but don't use the gate mechanism.
  44  */
  45 #define __HAVE_ARCH_GATE_AREA           1
  46
  47 /*
  48  * If the Kconfig doesn't specify, set a maximum zone order that
  49  * is enough so that we can create huge pages from small pages given
  50  * the respective sizes of the two page types.  See <linux/mmzone.h>.
  51  */
  52 #ifndef CONFIG_FORCE_MAX_ZONEORDER
  53 #define CONFIG_FORCE_MAX_ZONEORDER (HPAGE_SHIFT - PAGE_SHIFT + 1)
  54 #endif
  55
  56 #ifndef __ASSEMBLY__
  57
  58 #include <linux/types.h>
  59 #include <linux/string.h>
  60
  61 struct page;
  62
  63 static inline void clear_page(void *page)
  64 {
  65         memset(page, 0, PAGE_SIZE);
  66 }
  67
  68 static inline void copy_page(void *to, void *from)
  69 {
  70         memcpy(to, from, PAGE_SIZE);
  71 }
  72
  73 static inline void clear_user_page(void *page, unsigned long vaddr,
  74                                 struct page *pg)
  75 {
  76         clear_page(page);
  77 }
  78
  79 static inline void copy_user_page(void *to, void *from, unsigned long vaddr,
  80                                 struct page *topage)
  81 {
  82         copy_page(to, from);
  83 }
  84
  85 /*
  86  * Hypervisor page tables are made of the same basic structure.
  87  */
  88
  89 typedef HV_PTE pte_t;
  90 typedef HV_PTE pgd_t;
  91 typedef HV_PTE pgprot_t;
  92
  93 /*
  94  * User L2 page tables are managed as one L2 page table per page,
  95  * because we use the page allocator for them.  This keeps the allocation
  96  * simple, but it's also inefficient, since L2 page tables are much smaller
  97  * than pages (currently 2KB vs 64KB).  So we should revisit this.
  98  */
  99 typedef struct page *pgtable_t;
 100
 101 /* Must be a macro since it is used to create constants. */
 102 #define __pgprot(val) hv_pte(val)
 103
 104 /* Rarely-used initializers, typically with a "zero" value. */
 105 #define __pte(x) hv_pte(x)
 106 #define __pgd(x) hv_pte(x)
 107
 108 static inline u64 pgprot_val(pgprot_t pgprot)
 109 {
 110         return hv_pte_val(pgprot);
 111 }
 112
 113 static inline u64 pte_val(pte_t pte)
 114 {
 115         return hv_pte_val(pte);
 116 }
 117
 118 static inline u64 pgd_val(pgd_t pgd)
 119 {
 120         return hv_pte_val(pgd);
 121 }
 122
 123 #ifdef __tilegx__
 124
 125 typedef HV_PTE pmd_t;
 126
 127 #define __pmd(x) hv_pte(x)
 128
 129 static inline u64 pmd_val(pmd_t pmd)
 130 {
 131         return hv_pte_val(pmd);
 132 }
 133
 134 #endif
 135
 136 static inline __attribute_const__ int get_order(unsigned long size)
 137 {
 138         return BITS_PER_LONG - __builtin_clzl((size - 1) >> PAGE_SHIFT);
 139 }
 140
 141 #endif /* !__ASSEMBLY__ */
 142
 143 #define HUGETLB_PAGE_ORDER      (HPAGE_SHIFT - PAGE_SHIFT)
 144
 145 #define HUGE_MAX_HSTATE         6
 146
 147 #ifdef CONFIG_HUGETLB_PAGE
 148 #define HAVE_ARCH_HUGETLB_UNMAPPED_AREA
 149 #endif
 150
 151 /* Each memory controller has PAs distinct in their high bits. */
 152 #define NR_PA_HIGHBIT_SHIFT (CHIP_PA_WIDTH() - CHIP_LOG_NUM_MSHIMS())
 153 #define NR_PA_HIGHBIT_VALUES (1 << CHIP_LOG_NUM_MSHIMS())
 154 #define __pa_to_highbits(pa) ((phys_addr_t)(pa) >> NR_PA_HIGHBIT_SHIFT)
 155 #define __pfn_to_highbits(pfn) ((pfn) >> (NR_PA_HIGHBIT_SHIFT - PAGE_SHIFT))
 156
 157 #ifdef __tilegx__
 158
 159 /*
 160  * We reserve the lower half of memory for user-space programs, and the
 161  * upper half for system code.  We re-map all of physical memory in the
 162  * upper half, which takes a quarter of our VA space.  Then we have
 163  * the vmalloc regions.  The supervisor code lives at 0xfffffff700000000,
 164  * with the hypervisor above that.
 165  *
 166  * Loadable kernel modules are placed immediately after the static
 167  * supervisor code, with each being allocated a 256MB region of
 168  * address space, so we don't have to worry about the range of "jal"
 169  * and other branch instructions.
 170  *
 171  * For now we keep life simple and just allocate one pmd (4GB) for vmalloc.
 172  * Similarly, for now we don't play any struct page mapping games.
 173  */
 174
 175 #if CHIP_PA_WIDTH() + 2 > CHIP_VA_WIDTH()
 176 # error Too much PA to map with the VA available!
 177 #endif
 178 #define HALF_VA_SPACE           (_AC(1, UL) << (CHIP_VA_WIDTH() - 1))
 179
 180 #define MEM_LOW_END             (HALF_VA_SPACE - 1)         /* low half */
 181 #define MEM_HIGH_START          (-HALF_VA_SPACE)            /* high half */
 182 #define PAGE_OFFSET             MEM_HIGH_START
 183 #define FIXADDR_BASE            _AC(0xfffffff400000000, UL) /* 4 GB */
 184 #define FIXADDR_TOP             _AC(0xfffffff500000000, UL) /* 4 GB */
 185 #define _VMALLOC_START          FIXADDR_TOP
 186 #define HUGE_VMAP_BASE          _AC(0xfffffff600000000, UL) /* 4 GB */
 187 #define MEM_SV_START            _AC(0xfffffff700000000, UL) /* 256 MB */
 188 #define MEM_SV_INTRPT           MEM_SV_START
 189 #define MEM_MODULE_START        _AC(0xfffffff710000000, UL) /* 256 MB */
 190 #define MEM_MODULE_END          (MEM_MODULE_START + (256*1024*1024))
 191 #define MEM_HV_START            _AC(0xfffffff800000000, UL) /* 32 GB */
 192
 193 /* Highest DTLB address we will use */
 194 #define KERNEL_HIGH_VADDR       MEM_SV_START
 195
 196 #else /* !__tilegx__ */
 197
 198 /*
 199  * A PAGE_OFFSET of 0xC0000000 means that the kernel has
 200  * a virtual address space of one gigabyte, which limits the
 201  * amount of physical memory you can use to about 768MB.
 202  * If you want more physical memory than this then see the CONFIG_HIGHMEM
 203  * option in the kernel configuration.
 204  *
 205  * The top 16MB chunk in the table below is unavailable to Linux.  Since
 206  * the kernel interrupt vectors must live at ether 0xfe000000 or 0xfd000000
 207  * (depending on whether the kernel is at PL2 or Pl1), we map all of the
 208  * bottom of RAM at this address with a huge page table entry to minimize
 209  * its ITLB footprint (as well as at PAGE_OFFSET).  The last architected
 210  * requirement is that user interrupt vectors live at 0xfc000000, so we
 211  * make that range of memory available to user processes.  The remaining
 212  * regions are sized as shown; the first four addresses use the PL 1
 213  * values, and after that, we show "typical" values, since the actual
 214  * addresses depend on kernel #defines.
 215  *
 216  * MEM_HV_INTRPT                   0xfe000000
 217  * MEM_SV_INTRPT (kernel code)     0xfd000000
 218  * MEM_USER_INTRPT (user vector)   0xfc000000
 219  * FIX_KMAP_xxx                    0xf8000000 (via NR_CPUS * KM_TYPE_NR)
 220  * PKMAP_BASE                      0xf7000000 (via LAST_PKMAP)
 221  * HUGE_VMAP                       0xf3000000 (via CONFIG_NR_HUGE_VMAPS)
 222  * VMALLOC_START                   0xf0000000 (via __VMALLOC_RESERVE)
 223  * mapped LOWMEM                   0xc0000000
 224  */
 225
 226 #define MEM_USER_INTRPT         _AC(0xfc000000, UL)
 227 #if CONFIG_KERNEL_PL == 1
 228 #define MEM_SV_INTRPT           _AC(0xfd000000, UL)
 229 #define MEM_HV_INTRPT           _AC(0xfe000000, UL)
 230 #else
 231 #define MEM_GUEST_INTRPT        _AC(0xfd000000, UL)
 232 #define MEM_SV_INTRPT           _AC(0xfe000000, UL)
 233 #define MEM_HV_INTRPT           _AC(0xff000000, UL)
 234 #endif
 235
 236 #define INTRPT_SIZE             0x4000
 237
 238 /* Tolerate page size larger than the architecture interrupt region size. */
 239 #if PAGE_SIZE > INTRPT_SIZE
 240 #undef INTRPT_SIZE
 241 #define INTRPT_SIZE PAGE_SIZE
 242 #endif
 243
 244 #define KERNEL_HIGH_VADDR       MEM_USER_INTRPT
 245 #define FIXADDR_TOP             (KERNEL_HIGH_VADDR - PAGE_SIZE)
 246
 247 #define PAGE_OFFSET             _AC(CONFIG_PAGE_OFFSET, UL)
 248
 249 /* On 32-bit architectures we mix kernel modules in with other vmaps. */
 250 #define MEM_MODULE_START        VMALLOC_START
 251 #define MEM_MODULE_END          VMALLOC_END
 252
 253 #endif /* __tilegx__ */
 254
 255 #if !defined(__ASSEMBLY__) && !defined(VDSO_BUILD)
 256
 257 #ifdef CONFIG_HIGHMEM
 258
 259 /* Map kernel virtual addresses to page frames, in HPAGE_SIZE chunks. */
 260 extern unsigned long pbase_map[];
 261 extern void *vbase_map[];
 262
 263 static inline unsigned long kaddr_to_pfn(const volatile void *_kaddr)
 264 {
 265         unsigned long kaddr = (unsigned long)_kaddr;
 266         return pbase_map[kaddr >> HPAGE_SHIFT] +
 267                 ((kaddr & (HPAGE_SIZE - 1)) >> PAGE_SHIFT);
 268 }
 269
 270 static inline void *pfn_to_kaddr(unsigned long pfn)
 271 {
 272         return vbase_map[__pfn_to_highbits(pfn)] + (pfn << PAGE_SHIFT);
 273 }
 274
 275 static inline phys_addr_t virt_to_phys(const volatile void *kaddr)
 276 {
 277         unsigned long pfn = kaddr_to_pfn(kaddr);
 278         return ((phys_addr_t)pfn << PAGE_SHIFT) +
 279                 ((unsigned long)kaddr & (PAGE_SIZE-1));
 280 }
 281
 282 static inline void *phys_to_virt(phys_addr_t paddr)
 283 {
 284         return pfn_to_kaddr(paddr >> PAGE_SHIFT) + (paddr & (PAGE_SIZE-1));
 285 }
 286
 287 /* With HIGHMEM, we pack PAGE_OFFSET through high_memory with all valid VAs. */
 288 static inline int virt_addr_valid(const volatile void *kaddr)
 289 {
 290         extern void *high_memory;  /* copied from <linux/mm.h> */
 291         return ((unsigned long)kaddr >= PAGE_OFFSET && kaddr < high_memory);
 292 }
 293
 294 #else /* !CONFIG_HIGHMEM */
 295
 296 static inline unsigned long kaddr_to_pfn(const volatile void *kaddr)
 297 {
 298         return ((unsigned long)kaddr - PAGE_OFFSET) >> PAGE_SHIFT;
 299 }
 300
 301 static inline void *pfn_to_kaddr(unsigned long pfn)
 302 {
 303         return (void *)((pfn << PAGE_SHIFT) + PAGE_OFFSET);
 304 }
 305
 306 static inline phys_addr_t virt_to_phys(const volatile void *kaddr)
 307 {
 308         return (phys_addr_t)((unsigned long)kaddr - PAGE_OFFSET);
 309 }
 310
 311 static inline void *phys_to_virt(phys_addr_t paddr)
 312 {
 313         return (void *)((unsigned long)paddr + PAGE_OFFSET);
 314 }
 315
 316 /* Check that the given address is within some mapped range of PAs. */
 317 #define virt_addr_valid(kaddr) pfn_valid(kaddr_to_pfn(kaddr))
 318
 319 #endif /* !CONFIG_HIGHMEM */
 320
 321 /* All callers are not consistent in how they call these functions. */
 322 #define __pa(kaddr) virt_to_phys((void *)(unsigned long)(kaddr))
 323 #define __va(paddr) phys_to_virt((phys_addr_t)(paddr))
 324
 325 extern int devmem_is_allowed(unsigned long pagenr);
 326
 327 #ifdef CONFIG_FLATMEM
 328 static inline int pfn_valid(unsigned long pfn)
 329 {
 330         return pfn < max_mapnr;
 331 }
 332 #endif
 333
 334 /* Provide as macros since these require some other headers included. */
 335 #define page_to_pa(page) ((phys_addr_t)(page_to_pfn(page)) << PAGE_SHIFT)
 336 #define virt_to_page(kaddr) pfn_to_page(kaddr_to_pfn((void *)(kaddr)))
 337 #define page_to_virt(page) pfn_to_kaddr(page_to_pfn(page))
 338
 339 struct mm_struct;
 340 extern pte_t *virt_to_pte(struct mm_struct *mm, unsigned long addr);
 341
 342 #endif /* !__ASSEMBLY__ */
 343
 344 #define VM_DATA_DEFAULT_FLAGS \
 345         (VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
 346
 347 #include <asm-generic/memory_model.h>
 348
 349 #endif /* _ASM_TILE_PAGE_H */