arch/sparc/mm/init_32.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  linux/arch/sparc/mm/init.c
   4  *
   5  *  Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
   6  *  Copyright (C) 1995 Eddie C. Dost (ecd@skynet.be)
   7  *  Copyright (C) 1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
   8  *  Copyright (C) 2000 Anton Blanchard (anton@samba.org)
   9  */
  10
  11 #include <linux/module.h>
  12 #include <linux/signal.h>
  13 #include <linux/sched.h>
  14 #include <linux/kernel.h>
  15 #include <linux/errno.h>
  16 #include <linux/string.h>
  17 #include <linux/types.h>
  18 #include <linux/ptrace.h>
  19 #include <linux/mman.h>
  20 #include <linux/mm.h>
  21 #include <linux/swap.h>
  22 #include <linux/initrd.h>
  23 #include <linux/init.h>
  24 #include <linux/highmem.h>
  25 #include <linux/bootmem.h>
  26 #include <linux/pagemap.h>
  27 #include <linux/poison.h>
  28 #include <linux/gfp.h>
  29
  30 #include <asm/sections.h>
  31 #include <asm/page.h>
  32 #include <asm/pgtable.h>
  33 #include <asm/vaddrs.h>
  34 #include <asm/pgalloc.h>        /* bug in asm-generic/tlb.h: check_pgt_cache */
  35 #include <asm/setup.h>
  36 #include <asm/tlb.h>
  37 #include <asm/prom.h>
  38 #include <asm/leon.h>
  39
  40 #include "mm_32.h"
  41
  42 unsigned long *sparc_valid_addr_bitmap;
  43 EXPORT_SYMBOL(sparc_valid_addr_bitmap);
  44
  45 unsigned long phys_base;
  46 EXPORT_SYMBOL(phys_base);
  47
  48 unsigned long pfn_base;
  49 EXPORT_SYMBOL(pfn_base);
  50
  51 struct sparc_phys_banks sp_banks[SPARC_PHYS_BANKS+1];
  52
  53 /* Initial ramdisk setup */
  54 extern unsigned int sparc_ramdisk_image;
  55 extern unsigned int sparc_ramdisk_size;
  56
  57 unsigned long highstart_pfn, highend_pfn;
  58
  59 unsigned long last_valid_pfn;
  60
  61 unsigned long calc_highpages(void)
  62 {
  63         int i;
  64         int nr = 0;
  65
  66         for (i = 0; sp_banks[i].num_bytes != 0; i++) {
  67                 unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
  68                 unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
  69
  70                 if (end_pfn <= max_low_pfn)
  71                         continue;
  72
  73                 if (start_pfn < max_low_pfn)
  74                         start_pfn = max_low_pfn;
  75
  76                 nr += end_pfn - start_pfn;
  77         }
  78
  79         return nr;
  80 }
  81
  82 static unsigned long calc_max_low_pfn(void)
  83 {
  84         int i;
  85         unsigned long tmp = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
  86         unsigned long curr_pfn, last_pfn;
  87
  88         last_pfn = (sp_banks[0].base_addr + sp_banks[0].num_bytes) >> PAGE_SHIFT;
  89         for (i = 1; sp_banks[i].num_bytes != 0; i++) {
  90                 curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
  91
  92                 if (curr_pfn >= tmp) {
  93                         if (last_pfn < tmp)
  94                                 tmp = last_pfn;
  95                         break;
  96                 }
  97
  98                 last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
  99         }
 100
 101         return tmp;
 102 }
 103
 104 unsigned long __init bootmem_init(unsigned long *pages_avail)
 105 {
 106         unsigned long bootmap_size, start_pfn;
 107         unsigned long end_of_phys_memory = 0UL;
 108         unsigned long bootmap_pfn, bytes_avail, size;
 109         int i;
 110
 111         bytes_avail = 0UL;
 112         for (i = 0; sp_banks[i].num_bytes != 0; i++) {
 113                 end_of_phys_memory = sp_banks[i].base_addr +
 114                         sp_banks[i].num_bytes;
 115                 bytes_avail += sp_banks[i].num_bytes;
 116                 if (cmdline_memory_size) {
 117                         if (bytes_avail > cmdline_memory_size) {
 118                                 unsigned long slack = bytes_avail - cmdline_memory_size;
 119
 120                                 bytes_avail -= slack;
 121                                 end_of_phys_memory -= slack;
 122
 123                                 sp_banks[i].num_bytes -= slack;
 124                                 if (sp_banks[i].num_bytes == 0) {
 125                                         sp_banks[i].base_addr = 0xdeadbeef;
 126                                 } else {
 127                                         sp_banks[i+1].num_bytes = 0;
 128                                         sp_banks[i+1].base_addr = 0xdeadbeef;
 129                                 }
 130                                 break;
 131                         }
 132                 }
 133         }
 134
 135         /* Start with page aligned address of last symbol in kernel
 136          * image.
 137          */
 138         start_pfn  = (unsigned long)__pa(PAGE_ALIGN((unsigned long) &_end));
 139
 140         /* Now shift down to get the real physical page frame number. */
 141         start_pfn >>= PAGE_SHIFT;
 142
 143         bootmap_pfn = start_pfn;
 144
 145         max_pfn = end_of_phys_memory >> PAGE_SHIFT;
 146
 147         max_low_pfn = max_pfn;
 148         highstart_pfn = highend_pfn = max_pfn;
 149
 150         if (max_low_pfn > pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT)) {
 151                 highstart_pfn = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
 152                 max_low_pfn = calc_max_low_pfn();
 153                 printk(KERN_NOTICE "%ldMB HIGHMEM available.\n",
 154                     calc_highpages() >> (20 - PAGE_SHIFT));
 155         }
 156
 157 #ifdef CONFIG_BLK_DEV_INITRD
 158         /* Now have to check initial ramdisk, so that bootmap does not overwrite it */
 159         if (sparc_ramdisk_image) {
 160                 if (sparc_ramdisk_image >= (unsigned long)&_end - 2 * PAGE_SIZE)
 161                         sparc_ramdisk_image -= KERNBASE;
 162                 initrd_start = sparc_ramdisk_image + phys_base;
 163                 initrd_end = initrd_start + sparc_ramdisk_size;
 164                 if (initrd_end > end_of_phys_memory) {
 165                         printk(KERN_CRIT "initrd extends beyond end of memory "
 166                                          "(0x%016lx > 0x%016lx)\ndisabling initrd\n",
 167                                initrd_end, end_of_phys_memory);
 168                         initrd_start = 0;
 169                 }
 170                 if (initrd_start) {
 171                         if (initrd_start >= (start_pfn << PAGE_SHIFT) &&
 172                             initrd_start < (start_pfn << PAGE_SHIFT) + 2 * PAGE_SIZE)
 173                                 bootmap_pfn = PAGE_ALIGN (initrd_end) >> PAGE_SHIFT;
 174                 }
 175         }
 176 #endif
 177         /* Initialize the boot-time allocator. */
 178         bootmap_size = init_bootmem_node(NODE_DATA(0), bootmap_pfn, pfn_base,
 179                                          max_low_pfn);
 180
 181         /* Now register the available physical memory with the
 182          * allocator.
 183          */
 184         *pages_avail = 0;
 185         for (i = 0; sp_banks[i].num_bytes != 0; i++) {
 186                 unsigned long curr_pfn, last_pfn;
 187
 188                 curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
 189                 if (curr_pfn >= max_low_pfn)
 190                         break;
 191
 192                 last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
 193                 if (last_pfn > max_low_pfn)
 194                         last_pfn = max_low_pfn;
 195
 196                 /*
 197                  * .. finally, did all the rounding and playing
 198                  * around just make the area go away?
 199                  */
 200                 if (last_pfn <= curr_pfn)
 201                         continue;
 202
 203                 size = (last_pfn - curr_pfn) << PAGE_SHIFT;
 204                 *pages_avail += last_pfn - curr_pfn;
 205
 206                 free_bootmem(sp_banks[i].base_addr, size);
 207         }
 208
 209 #ifdef CONFIG_BLK_DEV_INITRD
 210         if (initrd_start) {
 211                 /* Reserve the initrd image area. */
 212                 size = initrd_end - initrd_start;
 213                 reserve_bootmem(initrd_start, size, BOOTMEM_DEFAULT);
 214                 *pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
 215
 216                 initrd_start = (initrd_start - phys_base) + PAGE_OFFSET;
 217                 initrd_end = (initrd_end - phys_base) + PAGE_OFFSET;
 218         }
 219 #endif
 220         /* Reserve the kernel text/data/bss. */
 221         size = (start_pfn << PAGE_SHIFT) - phys_base;
 222         reserve_bootmem(phys_base, size, BOOTMEM_DEFAULT);
 223         *pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
 224
 225         /* Reserve the bootmem map.   We do not account for it
 226          * in pages_avail because we will release that memory
 227          * in free_all_bootmem.
 228          */
 229         size = bootmap_size;
 230         reserve_bootmem((bootmap_pfn << PAGE_SHIFT), size, BOOTMEM_DEFAULT);
 231         *pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
 232
 233         return max_pfn;
 234 }
 235
 236 /*
 237  * paging_init() sets up the page tables: We call the MMU specific
 238  * init routine based upon the Sun model type on the Sparc.
 239  *
 240  */
 241 void __init paging_init(void)
 242 {
 243         srmmu_paging_init();
 244         prom_build_devicetree();
 245         of_fill_in_cpu_data();
 246         device_scan();
 247 }
 248
 249 static void __init taint_real_pages(void)
 250 {
 251         int i;
 252
 253         for (i = 0; sp_banks[i].num_bytes; i++) {
 254                 unsigned long start, end;
 255
 256                 start = sp_banks[i].base_addr;
 257                 end = start + sp_banks[i].num_bytes;
 258
 259                 while (start < end) {
 260                         set_bit(start >> 20, sparc_valid_addr_bitmap);
 261                         start += PAGE_SIZE;
 262                 }
 263         }
 264 }
 265
 266 static void map_high_region(unsigned long start_pfn, unsigned long end_pfn)
 267 {
 268         unsigned long tmp;
 269
 270 #ifdef CONFIG_DEBUG_HIGHMEM
 271         printk("mapping high region %08lx - %08lx\n", start_pfn, end_pfn);
 272 #endif
 273
 274         for (tmp = start_pfn; tmp < end_pfn; tmp++)
 275                 free_highmem_page(pfn_to_page(tmp));
 276 }
 277
 278 void __init mem_init(void)
 279 {
 280         int i;
 281
 282         if (PKMAP_BASE+LAST_PKMAP*PAGE_SIZE >= FIXADDR_START) {
 283                 prom_printf("BUG: fixmap and pkmap areas overlap\n");
 284                 prom_printf("pkbase: 0x%lx pkend: 0x%lx fixstart 0x%lx\n",
 285                        PKMAP_BASE,
 286                        (unsigned long)PKMAP_BASE+LAST_PKMAP*PAGE_SIZE,
 287                        FIXADDR_START);
 288                 prom_printf("Please mail sparclinux@vger.kernel.org.\n");
 289                 prom_halt();
 290         }
 291
 292
 293         /* Saves us work later. */
 294         memset((void *)empty_zero_page, 0, PAGE_SIZE);
 295
 296         i = last_valid_pfn >> ((20 - PAGE_SHIFT) + 5);
 297         i += 1;
 298         sparc_valid_addr_bitmap = (unsigned long *)
 299                 __alloc_bootmem(i << 2, SMP_CACHE_BYTES, 0UL);
 300
 301         if (sparc_valid_addr_bitmap == NULL) {
 302                 prom_printf("mem_init: Cannot alloc valid_addr_bitmap.\n");
 303                 prom_halt();
 304         }
 305         memset(sparc_valid_addr_bitmap, 0, i << 2);
 306
 307         taint_real_pages();
 308
 309         max_mapnr = last_valid_pfn - pfn_base;
 310         high_memory = __va(max_low_pfn << PAGE_SHIFT);
 311         free_all_bootmem();
 312
 313         for (i = 0; sp_banks[i].num_bytes != 0; i++) {
 314                 unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
 315                 unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
 316
 317                 if (end_pfn <= highstart_pfn)
 318                         continue;
 319
 320                 if (start_pfn < highstart_pfn)
 321                         start_pfn = highstart_pfn;
 322
 323                 map_high_region(start_pfn, end_pfn);
 324         }
 325
 326         mem_init_print_info(NULL);
 327 }
 328
 329 void free_initmem (void)
 330 {
 331         free_initmem_default(POISON_FREE_INITMEM);
 332 }
 333
 334 #ifdef CONFIG_BLK_DEV_INITRD
 335 void free_initrd_mem(unsigned long start, unsigned long end)
 336 {
 337         free_reserved_area((void *)start, (void *)end, POISON_FREE_INITMEM,
 338                            "initrd");
 339 }
 340 #endif
 341
 342 void sparc_flush_page_to_ram(struct page *page)
 343 {
 344         unsigned long vaddr = (unsigned long)page_address(page);
 345
 346         if (vaddr)
 347                 __flush_page_to_ram(vaddr);
 348 }
 349 EXPORT_SYMBOL(sparc_flush_page_to_ram);