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