linux/arch/sparc/mm/init_32.c
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   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/memblock.h>
  27#include <linux/pagemap.h>
  28#include <linux/poison.h>
  29#include <linux/gfp.h>
  30
  31#include <asm/sections.h>
  32#include <asm/page.h>
  33#include <asm/pgtable.h>
  34#include <asm/vaddrs.h>
  35#include <asm/pgalloc.h>        /* bug in asm-generic/tlb.h: check_pgt_cache */
  36#include <asm/setup.h>
  37#include <asm/tlb.h>
  38#include <asm/prom.h>
  39#include <asm/leon.h>
  40
  41#include "mm_32.h"
  42
  43unsigned long *sparc_valid_addr_bitmap;
  44EXPORT_SYMBOL(sparc_valid_addr_bitmap);
  45
  46unsigned long phys_base;
  47EXPORT_SYMBOL(phys_base);
  48
  49unsigned long pfn_base;
  50EXPORT_SYMBOL(pfn_base);
  51
  52struct sparc_phys_banks sp_banks[SPARC_PHYS_BANKS+1];
  53
  54/* Initial ramdisk setup */
  55extern unsigned int sparc_ramdisk_image;
  56extern unsigned int sparc_ramdisk_size;
  57
  58unsigned long highstart_pfn, highend_pfn;
  59
  60unsigned long last_valid_pfn;
  61
  62unsigned long calc_highpages(void)
  63{
  64        int i;
  65        int nr = 0;
  66
  67        for (i = 0; sp_banks[i].num_bytes != 0; i++) {
  68                unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
  69                unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
  70
  71                if (end_pfn <= max_low_pfn)
  72                        continue;
  73
  74                if (start_pfn < max_low_pfn)
  75                        start_pfn = max_low_pfn;
  76
  77                nr += end_pfn - start_pfn;
  78        }
  79
  80        return nr;
  81}
  82
  83static unsigned long calc_max_low_pfn(void)
  84{
  85        int i;
  86        unsigned long tmp = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
  87        unsigned long curr_pfn, last_pfn;
  88
  89        last_pfn = (sp_banks[0].base_addr + sp_banks[0].num_bytes) >> PAGE_SHIFT;
  90        for (i = 1; sp_banks[i].num_bytes != 0; i++) {
  91                curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
  92
  93                if (curr_pfn >= tmp) {
  94                        if (last_pfn < tmp)
  95                                tmp = last_pfn;
  96                        break;
  97                }
  98
  99                last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
 100        }
 101
 102        return tmp;
 103}
 104
 105static void __init find_ramdisk(unsigned long end_of_phys_memory)
 106{
 107#ifdef CONFIG_BLK_DEV_INITRD
 108        unsigned long size;
 109
 110        /* Now have to check initial ramdisk, so that it won't pass
 111         * the end of memory
 112         */
 113        if (sparc_ramdisk_image) {
 114                if (sparc_ramdisk_image >= (unsigned long)&_end - 2 * PAGE_SIZE)
 115                        sparc_ramdisk_image -= KERNBASE;
 116                initrd_start = sparc_ramdisk_image + phys_base;
 117                initrd_end = initrd_start + sparc_ramdisk_size;
 118                if (initrd_end > end_of_phys_memory) {
 119                        printk(KERN_CRIT "initrd extends beyond end of memory "
 120                               "(0x%016lx > 0x%016lx)\ndisabling initrd\n",
 121                               initrd_end, end_of_phys_memory);
 122                        initrd_start = 0;
 123                } else {
 124                        /* Reserve the initrd image area. */
 125                        size = initrd_end - initrd_start;
 126                        memblock_reserve(initrd_start, size);
 127
 128                        initrd_start = (initrd_start - phys_base) + PAGE_OFFSET;
 129                        initrd_end = (initrd_end - phys_base) + PAGE_OFFSET;
 130                }
 131        }
 132#endif
 133}
 134
 135unsigned long __init bootmem_init(unsigned long *pages_avail)
 136{
 137        unsigned long start_pfn, bytes_avail, size;
 138        unsigned long end_of_phys_memory = 0;
 139        unsigned long high_pages = 0;
 140        int i;
 141
 142        memblock_set_bottom_up(true);
 143        memblock_allow_resize();
 144
 145        bytes_avail = 0UL;
 146        for (i = 0; sp_banks[i].num_bytes != 0; i++) {
 147                end_of_phys_memory = sp_banks[i].base_addr +
 148                        sp_banks[i].num_bytes;
 149                bytes_avail += sp_banks[i].num_bytes;
 150                if (cmdline_memory_size) {
 151                        if (bytes_avail > cmdline_memory_size) {
 152                                unsigned long slack = bytes_avail - cmdline_memory_size;
 153
 154                                bytes_avail -= slack;
 155                                end_of_phys_memory -= slack;
 156
 157                                sp_banks[i].num_bytes -= slack;
 158                                if (sp_banks[i].num_bytes == 0) {
 159                                        sp_banks[i].base_addr = 0xdeadbeef;
 160                                } else {
 161                                        memblock_add(sp_banks[i].base_addr,
 162                                                     sp_banks[i].num_bytes);
 163                                        sp_banks[i+1].num_bytes = 0;
 164                                        sp_banks[i+1].base_addr = 0xdeadbeef;
 165                                }
 166                                break;
 167                        }
 168                }
 169                memblock_add(sp_banks[i].base_addr, sp_banks[i].num_bytes);
 170        }
 171
 172        /* Start with page aligned address of last symbol in kernel
 173         * image.
 174         */
 175        start_pfn  = (unsigned long)__pa(PAGE_ALIGN((unsigned long) &_end));
 176
 177        /* Now shift down to get the real physical page frame number. */
 178        start_pfn >>= PAGE_SHIFT;
 179
 180        max_pfn = end_of_phys_memory >> PAGE_SHIFT;
 181
 182        max_low_pfn = max_pfn;
 183        highstart_pfn = highend_pfn = max_pfn;
 184
 185        if (max_low_pfn > pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT)) {
 186                highstart_pfn = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
 187                max_low_pfn = calc_max_low_pfn();
 188                high_pages = calc_highpages();
 189                printk(KERN_NOTICE "%ldMB HIGHMEM available.\n",
 190                    high_pages >> (20 - PAGE_SHIFT));
 191        }
 192
 193        find_ramdisk(end_of_phys_memory);
 194
 195        /* Reserve the kernel text/data/bss. */
 196        size = (start_pfn << PAGE_SHIFT) - phys_base;
 197        memblock_reserve(phys_base, size);
 198
 199        size = memblock_phys_mem_size() - memblock_reserved_size();
 200        *pages_avail = (size >> PAGE_SHIFT) - high_pages;
 201
 202        return max_pfn;
 203}
 204
 205/*
 206 * paging_init() sets up the page tables: We call the MMU specific
 207 * init routine based upon the Sun model type on the Sparc.
 208 *
 209 */
 210void __init paging_init(void)
 211{
 212        srmmu_paging_init();
 213        prom_build_devicetree();
 214        of_fill_in_cpu_data();
 215        device_scan();
 216}
 217
 218static void __init taint_real_pages(void)
 219{
 220        int i;
 221
 222        for (i = 0; sp_banks[i].num_bytes; i++) {
 223                unsigned long start, end;
 224
 225                start = sp_banks[i].base_addr;
 226                end = start + sp_banks[i].num_bytes;
 227
 228                while (start < end) {
 229                        set_bit(start >> 20, sparc_valid_addr_bitmap);
 230                        start += PAGE_SIZE;
 231                }
 232        }
 233}
 234
 235static void map_high_region(unsigned long start_pfn, unsigned long end_pfn)
 236{
 237        unsigned long tmp;
 238
 239#ifdef CONFIG_DEBUG_HIGHMEM
 240        printk("mapping high region %08lx - %08lx\n", start_pfn, end_pfn);
 241#endif
 242
 243        for (tmp = start_pfn; tmp < end_pfn; tmp++)
 244                free_highmem_page(pfn_to_page(tmp));
 245}
 246
 247void __init mem_init(void)
 248{
 249        int i;
 250
 251        if (PKMAP_BASE+LAST_PKMAP*PAGE_SIZE >= FIXADDR_START) {
 252                prom_printf("BUG: fixmap and pkmap areas overlap\n");
 253                prom_printf("pkbase: 0x%lx pkend: 0x%lx fixstart 0x%lx\n",
 254                       PKMAP_BASE,
 255                       (unsigned long)PKMAP_BASE+LAST_PKMAP*PAGE_SIZE,
 256                       FIXADDR_START);
 257                prom_printf("Please mail sparclinux@vger.kernel.org.\n");
 258                prom_halt();
 259        }
 260
 261
 262        /* Saves us work later. */
 263        memset((void *)empty_zero_page, 0, PAGE_SIZE);
 264
 265        i = last_valid_pfn >> ((20 - PAGE_SHIFT) + 5);
 266        i += 1;
 267        sparc_valid_addr_bitmap = (unsigned long *)
 268                __alloc_bootmem(i << 2, SMP_CACHE_BYTES, 0UL);
 269
 270        if (sparc_valid_addr_bitmap == NULL) {
 271                prom_printf("mem_init: Cannot alloc valid_addr_bitmap.\n");
 272                prom_halt();
 273        }
 274        memset(sparc_valid_addr_bitmap, 0, i << 2);
 275
 276        taint_real_pages();
 277
 278        max_mapnr = last_valid_pfn - pfn_base;
 279        high_memory = __va(max_low_pfn << PAGE_SHIFT);
 280        free_all_bootmem();
 281
 282        for (i = 0; sp_banks[i].num_bytes != 0; i++) {
 283                unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
 284                unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
 285
 286                if (end_pfn <= highstart_pfn)
 287                        continue;
 288
 289                if (start_pfn < highstart_pfn)
 290                        start_pfn = highstart_pfn;
 291
 292                map_high_region(start_pfn, end_pfn);
 293        }
 294
 295        mem_init_print_info(NULL);
 296}
 297
 298void free_initmem (void)
 299{
 300        free_initmem_default(POISON_FREE_INITMEM);
 301}
 302
 303#ifdef CONFIG_BLK_DEV_INITRD
 304void free_initrd_mem(unsigned long start, unsigned long end)
 305{
 306        free_reserved_area((void *)start, (void *)end, POISON_FREE_INITMEM,
 307                           "initrd");
 308}
 309#endif
 310
 311void sparc_flush_page_to_ram(struct page *page)
 312{
 313        unsigned long vaddr = (unsigned long)page_address(page);
 314
 315        if (vaddr)
 316                __flush_page_to_ram(vaddr);
 317}
 318EXPORT_SYMBOL(sparc_flush_page_to_ram);
 319