arch/microblaze/mm/init.c

   1 /*
   2  * Copyright (C) 2007-2008 Michal Simek <monstr@monstr.eu>
   3  * Copyright (C) 2006 Atmark Techno, Inc.
   4  *
   5  * This file is subject to the terms and conditions of the GNU General Public
   6  * License. See the file "COPYING" in the main directory of this archive
   7  * for more details.
   8  */
   9
  10 #include <linux/dma-contiguous.h>
  11 #include <linux/memblock.h>
  12 #include <linux/init.h>
  13 #include <linux/kernel.h>
  14 #include <linux/mm.h> /* mem_init */
  15 #include <linux/initrd.h>
  16 #include <linux/pagemap.h>
  17 #include <linux/pfn.h>
  18 #include <linux/slab.h>
  19 #include <linux/swap.h>
  20 #include <linux/export.h>
  21
  22 #include <asm/page.h>
  23 #include <asm/mmu_context.h>
  24 #include <asm/pgalloc.h>
  25 #include <asm/sections.h>
  26 #include <asm/tlb.h>
  27 #include <asm/fixmap.h>
  28
  29 /* Use for MMU and noMMU because of PCI generic code */
  30 int mem_init_done;
  31
  32 #ifndef CONFIG_MMU
  33 unsigned int __page_offset;
  34 EXPORT_SYMBOL(__page_offset);
  35 #endif /* CONFIG_MMU */
  36
  37 char *klimit = _end;
  38
  39 /*
  40  * Initialize the bootmem system and give it all the memory we
  41  * have available.
  42  */
  43 unsigned long memory_start;
  44 EXPORT_SYMBOL(memory_start);
  45 unsigned long memory_size;
  46 EXPORT_SYMBOL(memory_size);
  47 unsigned long lowmem_size;
  48
  49 #ifdef CONFIG_HIGHMEM
  50 pte_t *kmap_pte;
  51 EXPORT_SYMBOL(kmap_pte);
  52 pgprot_t kmap_prot;
  53 EXPORT_SYMBOL(kmap_prot);
  54
  55 static inline pte_t *virt_to_kpte(unsigned long vaddr)
  56 {
  57         pgd_t *pgd = pgd_offset_k(vaddr);
  58         p4d_t *p4d = p4d_offset(pgd, vaddr);
  59         pud_t *pud = pud_offset(p4d, vaddr);
  60
  61         return pte_offset_kernel(pmd_offset(pud, vaddr), vaddr);
  62 }
  63
  64 static void __init highmem_init(void)
  65 {
  66         pr_debug("%x\n", (u32)PKMAP_BASE);
  67         map_page(PKMAP_BASE, 0, 0);     /* XXX gross */
  68         pkmap_page_table = virt_to_kpte(PKMAP_BASE);
  69
  70         kmap_pte = virt_to_kpte(__fix_to_virt(FIX_KMAP_BEGIN));
  71         kmap_prot = PAGE_KERNEL;
  72 }
  73
  74 static void highmem_setup(void)
  75 {
  76         unsigned long pfn;
  77
  78         for (pfn = max_low_pfn; pfn < max_pfn; ++pfn) {
  79                 struct page *page = pfn_to_page(pfn);
  80
  81                 /* FIXME not sure about */
  82                 if (!memblock_is_reserved(pfn << PAGE_SHIFT))
  83                         free_highmem_page(page);
  84         }
  85 }
  86 #endif /* CONFIG_HIGHMEM */
  87
  88 /*
  89  * paging_init() sets up the page tables - in fact we've already done this.
  90  */
  91 static void __init paging_init(void)
  92 {
  93         unsigned long zones_size[MAX_NR_ZONES];
  94 #ifdef CONFIG_MMU
  95         int idx;
  96
  97         /* Setup fixmaps */
  98         for (idx = 0; idx < __end_of_fixed_addresses; idx++)
  99                 clear_fixmap(idx);
 100 #endif
 101
 102         /* Clean every zones */
 103         memset(zones_size, 0, sizeof(zones_size));
 104
 105 #ifdef CONFIG_HIGHMEM
 106         highmem_init();
 107
 108         zones_size[ZONE_DMA] = max_low_pfn;
 109         zones_size[ZONE_HIGHMEM] = max_pfn;
 110 #else
 111         zones_size[ZONE_DMA] = max_pfn;
 112 #endif
 113
 114         /* We don't have holes in memory map */
 115         free_area_init_nodes(zones_size);
 116 }
 117
 118 void __init setup_memory(void)
 119 {
 120         struct memblock_region *reg;
 121
 122 #ifndef CONFIG_MMU
 123         u32 kernel_align_start, kernel_align_size;
 124
 125         /* Find main memory where is the kernel */
 126         for_each_memblock(memory, reg) {
 127                 memory_start = (u32)reg->base;
 128                 lowmem_size = reg->size;
 129                 if ((memory_start <= (u32)_text) &&
 130                         ((u32)_text <= (memory_start + lowmem_size - 1))) {
 131                         memory_size = lowmem_size;
 132                         PAGE_OFFSET = memory_start;
 133                         pr_info("%s: Main mem: 0x%x, size 0x%08x\n",
 134                                 __func__, (u32) memory_start,
 135                                         (u32) memory_size);
 136                         break;
 137                 }
 138         }
 139
 140         if (!memory_start || !memory_size) {
 141                 panic("%s: Missing memory setting 0x%08x, size=0x%08x\n",
 142                         __func__, (u32) memory_start, (u32) memory_size);
 143         }
 144
 145         /* reservation of region where is the kernel */
 146         kernel_align_start = PAGE_DOWN((u32)_text);
 147         /* ALIGN can be remove because _end in vmlinux.lds.S is align */
 148         kernel_align_size = PAGE_UP((u32)klimit) - kernel_align_start;
 149         pr_info("%s: kernel addr:0x%08x-0x%08x size=0x%08x\n",
 150                 __func__, kernel_align_start, kernel_align_start
 151                         + kernel_align_size, kernel_align_size);
 152         memblock_reserve(kernel_align_start, kernel_align_size);
 153 #endif
 154         /*
 155          * Kernel:
 156          * start: base phys address of kernel - page align
 157          * end: base phys address of kernel - page align
 158          *
 159          * min_low_pfn - the first page (mm/bootmem.c - node_boot_start)
 160          * max_low_pfn
 161          * max_mapnr - the first unused page (mm/bootmem.c - node_low_pfn)
 162          */
 163
 164         /* memory start is from the kernel end (aligned) to higher addr */
 165         min_low_pfn = memory_start >> PAGE_SHIFT; /* minimum for allocation */
 166         /* RAM is assumed contiguous */
 167         max_mapnr = memory_size >> PAGE_SHIFT;
 168         max_low_pfn = ((u64)memory_start + (u64)lowmem_size) >> PAGE_SHIFT;
 169         max_pfn = ((u64)memory_start + (u64)memory_size) >> PAGE_SHIFT;
 170
 171         pr_info("%s: max_mapnr: %#lx\n", __func__, max_mapnr);
 172         pr_info("%s: min_low_pfn: %#lx\n", __func__, min_low_pfn);
 173         pr_info("%s: max_low_pfn: %#lx\n", __func__, max_low_pfn);
 174         pr_info("%s: max_pfn: %#lx\n", __func__, max_pfn);
 175
 176         /* Add active regions with valid PFNs */
 177         for_each_memblock(memory, reg) {
 178                 unsigned long start_pfn, end_pfn;
 179
 180                 start_pfn = memblock_region_memory_base_pfn(reg);
 181                 end_pfn = memblock_region_memory_end_pfn(reg);
 182                 memblock_set_node(start_pfn << PAGE_SHIFT,
 183                                   (end_pfn - start_pfn) << PAGE_SHIFT,
 184                                   &memblock.memory, 0);
 185         }
 186
 187         /* XXX need to clip this if using highmem? */
 188         sparse_memory_present_with_active_regions(0);
 189
 190         paging_init();
 191 }
 192
 193 void __init mem_init(void)
 194 {
 195         high_memory = (void *)__va(memory_start + lowmem_size - 1);
 196
 197         /* this will put all memory onto the freelists */
 198         memblock_free_all();
 199 #ifdef CONFIG_HIGHMEM
 200         highmem_setup();
 201 #endif
 202
 203         mem_init_print_info(NULL);
 204 #ifdef CONFIG_MMU
 205         pr_info("Kernel virtual memory layout:\n");
 206         pr_info("  * 0x%08lx..0x%08lx  : fixmap\n", FIXADDR_START, FIXADDR_TOP);
 207 #ifdef CONFIG_HIGHMEM
 208         pr_info("  * 0x%08lx..0x%08lx  : highmem PTEs\n",
 209                 PKMAP_BASE, PKMAP_ADDR(LAST_PKMAP));
 210 #endif /* CONFIG_HIGHMEM */
 211         pr_info("  * 0x%08lx..0x%08lx  : early ioremap\n",
 212                 ioremap_bot, ioremap_base);
 213         pr_info("  * 0x%08lx..0x%08lx  : vmalloc & ioremap\n",
 214                 (unsigned long)VMALLOC_START, VMALLOC_END);
 215 #endif
 216         mem_init_done = 1;
 217 }
 218
 219 #ifndef CONFIG_MMU
 220 int page_is_ram(unsigned long pfn)
 221 {
 222         return __range_ok(pfn, 0);
 223 }
 224 #else
 225 int page_is_ram(unsigned long pfn)
 226 {
 227         return pfn < max_low_pfn;
 228 }
 229
 230 /*
 231  * Check for command-line options that affect what MMU_init will do.
 232  */
 233 static void mm_cmdline_setup(void)
 234 {
 235         unsigned long maxmem = 0;
 236         char *p = cmd_line;
 237
 238         /* Look for mem= option on command line */
 239         p = strstr(cmd_line, "mem=");
 240         if (p) {
 241                 p += 4;
 242                 maxmem = memparse(p, &p);
 243                 if (maxmem && memory_size > maxmem) {
 244                         memory_size = maxmem;
 245                         memblock.memory.regions[0].size = memory_size;
 246                 }
 247         }
 248 }
 249
 250 /*
 251  * MMU_init_hw does the chip-specific initialization of the MMU hardware.
 252  */
 253 static void __init mmu_init_hw(void)
 254 {
 255         /*
 256          * The Zone Protection Register (ZPR) defines how protection will
 257          * be applied to every page which is a member of a given zone. At
 258          * present, we utilize only two of the zones.
 259          * The zone index bits (of ZSEL) in the PTE are used for software
 260          * indicators, except the LSB.  For user access, zone 1 is used,
 261          * for kernel access, zone 0 is used.  We set all but zone 1
 262          * to zero, allowing only kernel access as indicated in the PTE.
 263          * For zone 1, we set a 01 binary (a value of 10 will not work)
 264          * to allow user access as indicated in the PTE.  This also allows
 265          * kernel access as indicated in the PTE.
 266          */
 267         __asm__ __volatile__ ("ori r11, r0, 0x10000000;" \
 268                         "mts rzpr, r11;"
 269                         : : : "r11");
 270 }
 271
 272 /*
 273  * MMU_init sets up the basic memory mappings for the kernel,
 274  * including both RAM and possibly some I/O regions,
 275  * and sets up the page tables and the MMU hardware ready to go.
 276  */
 277
 278 /* called from head.S */
 279 asmlinkage void __init mmu_init(void)
 280 {
 281         unsigned int kstart, ksize;
 282
 283         if (!memblock.reserved.cnt) {
 284                 pr_emerg("Error memory count\n");
 285                 machine_restart(NULL);
 286         }
 287
 288         if ((u32) memblock.memory.regions[0].size < 0x400000) {
 289                 pr_emerg("Memory must be greater than 4MB\n");
 290                 machine_restart(NULL);
 291         }
 292
 293         if ((u32) memblock.memory.regions[0].size < kernel_tlb) {
 294                 pr_emerg("Kernel size is greater than memory node\n");
 295                 machine_restart(NULL);
 296         }
 297
 298         /* Find main memory where the kernel is */
 299         memory_start = (u32) memblock.memory.regions[0].base;
 300         lowmem_size = memory_size = (u32) memblock.memory.regions[0].size;
 301
 302         if (lowmem_size > CONFIG_LOWMEM_SIZE) {
 303                 lowmem_size = CONFIG_LOWMEM_SIZE;
 304 #ifndef CONFIG_HIGHMEM
 305                 memory_size = lowmem_size;
 306 #endif
 307         }
 308
 309         mm_cmdline_setup(); /* FIXME parse args from command line - not used */
 310
 311         /*
 312          * Map out the kernel text/data/bss from the available physical
 313          * memory.
 314          */
 315         kstart = __pa(CONFIG_KERNEL_START); /* kernel start */
 316         /* kernel size */
 317         ksize = PAGE_ALIGN(((u32)_end - (u32)CONFIG_KERNEL_START));
 318         memblock_reserve(kstart, ksize);
 319
 320 #if defined(CONFIG_BLK_DEV_INITRD)
 321         /* Remove the init RAM disk from the available memory. */
 322         if (initrd_start) {
 323                 unsigned long size;
 324                 size = initrd_end - initrd_start;
 325                 memblock_reserve(__virt_to_phys(initrd_start), size);
 326         }
 327 #endif /* CONFIG_BLK_DEV_INITRD */
 328
 329         /* Initialize the MMU hardware */
 330         mmu_init_hw();
 331
 332         /* Map in all of RAM starting at CONFIG_KERNEL_START */
 333         mapin_ram();
 334
 335         /* Extend vmalloc and ioremap area as big as possible */
 336 #ifdef CONFIG_HIGHMEM
 337         ioremap_base = ioremap_bot = PKMAP_BASE;
 338 #else
 339         ioremap_base = ioremap_bot = FIXADDR_START;
 340 #endif
 341
 342         /* Initialize the context management stuff */
 343         mmu_context_init();
 344
 345         /* Shortly after that, the entire linear mapping will be available */
 346         /* This will also cause that unflatten device tree will be allocated
 347          * inside 768MB limit */
 348         memblock_set_current_limit(memory_start + lowmem_size - 1);
 349
 350         /* CMA initialization */
 351         dma_contiguous_reserve(memory_start + lowmem_size - 1);
 352 }
 353
 354 /* This is only called until mem_init is done. */
 355 void __init *early_get_page(void)
 356 {
 357         /*
 358          * Mem start + kernel_tlb -> here is limit
 359          * because of mem mapping from head.S
 360          */
 361         return memblock_alloc_try_nid_raw(PAGE_SIZE, PAGE_SIZE,
 362                                 MEMBLOCK_LOW_LIMIT, memory_start + kernel_tlb,
 363                                 NUMA_NO_NODE);
 364 }
 365
 366 #endif /* CONFIG_MMU */
 367
 368 void * __ref zalloc_maybe_bootmem(size_t size, gfp_t mask)
 369 {
 370         void *p;
 371
 372         if (mem_init_done) {
 373                 p = kzalloc(size, mask);
 374         } else {
 375                 p = memblock_alloc(size, SMP_CACHE_BYTES);
 376                 if (!p)
 377                         panic("%s: Failed to allocate %zu bytes\n",
 378                               __func__, size);
 379         }
 380
 381         return p;
 382 }