arch/metag/mm/init.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  Copyright (C) 2005,2006,2007,2008,2009,2010 Imagination Technologies
   4  *
   5  */
   6
   7 #include <linux/export.h>
   8 #include <linux/mm.h>
   9 #include <linux/swap.h>
  10 #include <linux/init.h>
  11 #include <linux/bootmem.h>
  12 #include <linux/pagemap.h>
  13 #include <linux/percpu.h>
  14 #include <linux/memblock.h>
  15 #include <linux/initrd.h>
  16 #include <linux/sched/task.h>
  17
  18 #include <asm/setup.h>
  19 #include <asm/page.h>
  20 #include <asm/pgalloc.h>
  21 #include <asm/mmu.h>
  22 #include <asm/mmu_context.h>
  23 #include <asm/sections.h>
  24 #include <asm/tlb.h>
  25 #include <asm/user_gateway.h>
  26 #include <asm/mmzone.h>
  27 #include <asm/fixmap.h>
  28
  29 unsigned long pfn_base;
  30 EXPORT_SYMBOL(pfn_base);
  31
  32 pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_data;
  33
  34 unsigned long empty_zero_page;
  35 EXPORT_SYMBOL(empty_zero_page);
  36
  37 extern char __user_gateway_start;
  38 extern char __user_gateway_end;
  39
  40 void *gateway_page;
  41
  42 /*
  43  * Insert the gateway page into a set of page tables, creating the
  44  * page tables if necessary.
  45  */
  46 static void insert_gateway_page(pgd_t *pgd, unsigned long address)
  47 {
  48         pud_t *pud;
  49         pmd_t *pmd;
  50         pte_t *pte;
  51
  52         BUG_ON(!pgd_present(*pgd));
  53
  54         pud = pud_offset(pgd, address);
  55         BUG_ON(!pud_present(*pud));
  56
  57         pmd = pmd_offset(pud, address);
  58         if (!pmd_present(*pmd)) {
  59                 pte = alloc_bootmem_pages(PAGE_SIZE);
  60                 set_pmd(pmd, __pmd(_PAGE_TABLE | __pa(pte)));
  61         }
  62
  63         pte = pte_offset_kernel(pmd, address);
  64         set_pte(pte, pfn_pte(__pa(gateway_page) >> PAGE_SHIFT, PAGE_READONLY));
  65 }
  66
  67 /* Alloc and map a page in a known location accessible to userspace. */
  68 static void __init user_gateway_init(void)
  69 {
  70         unsigned long address = USER_GATEWAY_PAGE;
  71         int offset = pgd_index(address);
  72         pgd_t *pgd;
  73
  74         gateway_page = alloc_bootmem_pages(PAGE_SIZE);
  75
  76         pgd = swapper_pg_dir + offset;
  77         insert_gateway_page(pgd, address);
  78
  79 #ifdef CONFIG_METAG_META12
  80         /*
  81          * Insert the gateway page into our current page tables even
  82          * though we've already inserted it into our reference page
  83          * table (swapper_pg_dir). This is because with a META1 mmu we
  84          * copy just the user address range and not the gateway page
  85          * entry on context switch, see switch_mmu().
  86          */
  87         pgd = (pgd_t *)mmu_get_base() + offset;
  88         insert_gateway_page(pgd, address);
  89 #endif /* CONFIG_METAG_META12 */
  90
  91         BUG_ON((&__user_gateway_end - &__user_gateway_start) > PAGE_SIZE);
  92
  93         gateway_page += (address & ~PAGE_MASK);
  94
  95         memcpy(gateway_page, &__user_gateway_start,
  96                &__user_gateway_end - &__user_gateway_start);
  97
  98         /*
  99          * We don't need to flush the TLB here, there should be no mapping
 100          * present at boot for this address and only valid mappings are in
 101          * the TLB (apart from on Meta 1.x, but those cached invalid
 102          * mappings should be impossible to hit here).
 103          *
 104          * We don't flush the code cache here even though we have written
 105          * code through the data cache and they may not be coherent. At
 106          * this point we assume there is no stale data in the code cache
 107          * for this address so there is no need to flush.
 108          */
 109 }
 110
 111 static void __init allocate_pgdat(unsigned int nid)
 112 {
 113         unsigned long start_pfn, end_pfn;
 114 #ifdef CONFIG_NEED_MULTIPLE_NODES
 115         unsigned long phys;
 116 #endif
 117
 118         get_pfn_range_for_nid(nid, &start_pfn, &end_pfn);
 119
 120 #ifdef CONFIG_NEED_MULTIPLE_NODES
 121         phys = __memblock_alloc_base(sizeof(struct pglist_data),
 122                                 SMP_CACHE_BYTES, end_pfn << PAGE_SHIFT);
 123         /* Retry with all of system memory */
 124         if (!phys)
 125                 phys = __memblock_alloc_base(sizeof(struct pglist_data),
 126                                              SMP_CACHE_BYTES,
 127                                              memblock_end_of_DRAM());
 128         if (!phys)
 129                 panic("Can't allocate pgdat for node %d\n", nid);
 130
 131         NODE_DATA(nid) = __va(phys);
 132         memset(NODE_DATA(nid), 0, sizeof(struct pglist_data));
 133
 134         NODE_DATA(nid)->bdata = &bootmem_node_data[nid];
 135 #endif
 136
 137         NODE_DATA(nid)->node_start_pfn = start_pfn;
 138         NODE_DATA(nid)->node_spanned_pages = end_pfn - start_pfn;
 139 }
 140
 141 static void __init bootmem_init_one_node(unsigned int nid)
 142 {
 143         unsigned long total_pages, paddr;
 144         unsigned long end_pfn;
 145         struct pglist_data *p;
 146
 147         p = NODE_DATA(nid);
 148
 149         /* Nothing to do.. */
 150         if (!p->node_spanned_pages)
 151                 return;
 152
 153         end_pfn = pgdat_end_pfn(p);
 154 #ifdef CONFIG_HIGHMEM
 155         if (end_pfn > max_low_pfn)
 156                 end_pfn = max_low_pfn;
 157 #endif
 158
 159         total_pages = bootmem_bootmap_pages(end_pfn - p->node_start_pfn);
 160
 161         paddr = memblock_alloc(total_pages << PAGE_SHIFT, PAGE_SIZE);
 162         if (!paddr)
 163                 panic("Can't allocate bootmap for nid[%d]\n", nid);
 164
 165         init_bootmem_node(p, paddr >> PAGE_SHIFT, p->node_start_pfn, end_pfn);
 166
 167         free_bootmem_with_active_regions(nid, end_pfn);
 168
 169         /*
 170          * XXX Handle initial reservations for the system memory node
 171          * only for the moment, we'll refactor this later for handling
 172          * reservations in other nodes.
 173          */
 174         if (nid == 0) {
 175                 struct memblock_region *reg;
 176
 177                 /* Reserve the sections we're already using. */
 178                 for_each_memblock(reserved, reg) {
 179                         unsigned long size = reg->size;
 180
 181 #ifdef CONFIG_HIGHMEM
 182                         /* ...but not highmem */
 183                         if (PFN_DOWN(reg->base) >= highstart_pfn)
 184                                 continue;
 185
 186                         if (PFN_UP(reg->base + size) > highstart_pfn)
 187                                 size = (highstart_pfn - PFN_DOWN(reg->base))
 188                                        << PAGE_SHIFT;
 189 #endif
 190
 191                         reserve_bootmem(reg->base, size, BOOTMEM_DEFAULT);
 192                 }
 193         }
 194
 195         sparse_memory_present_with_active_regions(nid);
 196 }
 197
 198 static void __init do_init_bootmem(void)
 199 {
 200         struct memblock_region *reg;
 201         int i;
 202
 203         /* Add active regions with valid PFNs. */
 204         for_each_memblock(memory, reg) {
 205                 unsigned long start_pfn, end_pfn;
 206                 start_pfn = memblock_region_memory_base_pfn(reg);
 207                 end_pfn = memblock_region_memory_end_pfn(reg);
 208                 memblock_set_node(PFN_PHYS(start_pfn),
 209                                   PFN_PHYS(end_pfn - start_pfn),
 210                                   &memblock.memory, 0);
 211         }
 212
 213         /* All of system RAM sits in node 0 for the non-NUMA case */
 214         allocate_pgdat(0);
 215         node_set_online(0);
 216
 217         soc_mem_setup();
 218
 219         for_each_online_node(i)
 220                 bootmem_init_one_node(i);
 221
 222         sparse_init();
 223 }
 224
 225 extern char _heap_start[];
 226
 227 static void __init init_and_reserve_mem(void)
 228 {
 229         unsigned long start_pfn, heap_start;
 230         u64 base = min_low_pfn << PAGE_SHIFT;
 231         u64 size = (max_low_pfn << PAGE_SHIFT) - base;
 232
 233         heap_start = (unsigned long) &_heap_start;
 234
 235         memblock_add(base, size);
 236
 237         /*
 238          * Partially used pages are not usable - thus
 239          * we are rounding upwards:
 240          */
 241         start_pfn = PFN_UP(__pa(heap_start));
 242
 243         /*
 244          * Reserve the kernel text.
 245          */
 246         memblock_reserve(base, (PFN_PHYS(start_pfn) + PAGE_SIZE - 1) - base);
 247
 248 #ifdef CONFIG_HIGHMEM
 249         /*
 250          * Add & reserve highmem, so page structures are initialised.
 251          */
 252         base = highstart_pfn << PAGE_SHIFT;
 253         size = (highend_pfn << PAGE_SHIFT) - base;
 254         if (size) {
 255                 memblock_add(base, size);
 256                 memblock_reserve(base, size);
 257         }
 258 #endif
 259 }
 260
 261 #ifdef CONFIG_HIGHMEM
 262 /*
 263  * Ensure we have allocated page tables in swapper_pg_dir for the
 264  * fixed mappings range from 'start' to 'end'.
 265  */
 266 static void __init allocate_pgtables(unsigned long start, unsigned long end)
 267 {
 268         pgd_t *pgd;
 269         pmd_t *pmd;
 270         pte_t *pte;
 271         int i, j;
 272         unsigned long vaddr;
 273
 274         vaddr = start;
 275         i = pgd_index(vaddr);
 276         j = pmd_index(vaddr);
 277         pgd = swapper_pg_dir + i;
 278
 279         for ( ; (i < PTRS_PER_PGD) && (vaddr != end); pgd++, i++) {
 280                 pmd = (pmd_t *)pgd;
 281                 for (; (j < PTRS_PER_PMD) && (vaddr != end); pmd++, j++) {
 282                         vaddr += PMD_SIZE;
 283
 284                         if (!pmd_none(*pmd))
 285                                 continue;
 286
 287                         pte = (pte_t *)alloc_bootmem_low_pages(PAGE_SIZE);
 288                         pmd_populate_kernel(&init_mm, pmd, pte);
 289                 }
 290                 j = 0;
 291         }
 292 }
 293
 294 static void __init fixedrange_init(void)
 295 {
 296         unsigned long vaddr, end;
 297         pgd_t *pgd;
 298         pud_t *pud;
 299         pmd_t *pmd;
 300         pte_t *pte;
 301
 302         /*
 303          * Fixed mappings:
 304          */
 305         vaddr = __fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK;
 306         end = (FIXADDR_TOP + PMD_SIZE - 1) & PMD_MASK;
 307         allocate_pgtables(vaddr, end);
 308
 309         /*
 310          * Permanent kmaps:
 311          */
 312         vaddr = PKMAP_BASE;
 313         allocate_pgtables(vaddr, vaddr + PAGE_SIZE*LAST_PKMAP);
 314
 315         pgd = swapper_pg_dir + pgd_index(vaddr);
 316         pud = pud_offset(pgd, vaddr);
 317         pmd = pmd_offset(pud, vaddr);
 318         pte = pte_offset_kernel(pmd, vaddr);
 319         pkmap_page_table = pte;
 320 }
 321 #endif /* CONFIG_HIGHMEM */
 322
 323 /*
 324  * paging_init() continues the virtual memory environment setup which
 325  * was begun by the code in arch/metag/kernel/setup.c.
 326  */
 327 void __init paging_init(unsigned long mem_end)
 328 {
 329         unsigned long max_zone_pfns[MAX_NR_ZONES];
 330         int nid;
 331
 332         init_and_reserve_mem();
 333
 334         memblock_allow_resize();
 335
 336         memblock_dump_all();
 337
 338         nodes_clear(node_online_map);
 339
 340         init_new_context(&init_task, &init_mm);
 341
 342         memset(swapper_pg_dir, 0, sizeof(swapper_pg_dir));
 343
 344         do_init_bootmem();
 345         mmu_init(mem_end);
 346
 347 #ifdef CONFIG_HIGHMEM
 348         fixedrange_init();
 349         kmap_init();
 350 #endif
 351
 352         /* Initialize the zero page to a bootmem page, already zeroed. */
 353         empty_zero_page = (unsigned long)alloc_bootmem_pages(PAGE_SIZE);
 354
 355         user_gateway_init();
 356
 357         memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
 358
 359         for_each_online_node(nid) {
 360                 pg_data_t *pgdat = NODE_DATA(nid);
 361                 unsigned long low, start_pfn;
 362
 363                 start_pfn = pgdat->bdata->node_min_pfn;
 364                 low = pgdat->bdata->node_low_pfn;
 365
 366                 if (max_zone_pfns[ZONE_NORMAL] < low)
 367                         max_zone_pfns[ZONE_NORMAL] = low;
 368
 369 #ifdef CONFIG_HIGHMEM
 370                 max_zone_pfns[ZONE_HIGHMEM] = highend_pfn;
 371 #endif
 372                 pr_info("Node %u: start_pfn = 0x%lx, low = 0x%lx\n",
 373                         nid, start_pfn, low);
 374         }
 375
 376         free_area_init_nodes(max_zone_pfns);
 377 }
 378
 379 void __init mem_init(void)
 380 {
 381 #ifdef CONFIG_HIGHMEM
 382         unsigned long tmp;
 383
 384         /*
 385          * Explicitly reset zone->managed_pages because highmem pages are
 386          * freed before calling free_all_bootmem();
 387          */
 388         reset_all_zones_managed_pages();
 389         for (tmp = highstart_pfn; tmp < highend_pfn; tmp++)
 390                 free_highmem_page(pfn_to_page(tmp));
 391 #endif /* CONFIG_HIGHMEM */
 392
 393         free_all_bootmem();
 394         mem_init_print_info(NULL);
 395 }
 396
 397 void free_initmem(void)
 398 {
 399         free_initmem_default(POISON_FREE_INITMEM);
 400 }
 401
 402 #ifdef CONFIG_BLK_DEV_INITRD
 403 void free_initrd_mem(unsigned long start, unsigned long end)
 404 {
 405         free_reserved_area((void *)start, (void *)end, POISON_FREE_INITMEM,
 406                            "initrd");
 407 }
 408 #endif