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/memblock.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/vaddrs.h> 33 #include <asm/setup.h> 34 #include <asm/tlb.h> 35 #include <asm/prom.h> 36 #include <asm/leon.h> 37 38 #include "mm_32.h" 39 40 static unsigned long *sparc_valid_addr_bitmap; 41 42 unsigned long phys_base; 43 EXPORT_SYMBOL(phys_base); 44 45 unsigned long pfn_base; 46 EXPORT_SYMBOL(pfn_base); 47 48 struct sparc_phys_banks sp_banks[SPARC_PHYS_BANKS+1]; 49 50 /* Initial ramdisk setup */ 51 extern unsigned int sparc_ramdisk_image; 52 extern unsigned int sparc_ramdisk_size; 53 54 unsigned long highstart_pfn, highend_pfn; 55 56 unsigned long last_valid_pfn; 57 58 unsigned long calc_highpages(void) 59 { 60 int i; 61 int nr = 0; 62 63 for (i = 0; sp_banks[i].num_bytes != 0; i++) { 64 unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT; 65 unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT; 66 67 if (end_pfn <= max_low_pfn) 68 continue; 69 70 if (start_pfn < max_low_pfn) 71 start_pfn = max_low_pfn; 72 73 nr += end_pfn - start_pfn; 74 } 75 76 return nr; 77 } 78 79 static unsigned long calc_max_low_pfn(void) 80 { 81 int i; 82 unsigned long tmp = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT); 83 unsigned long curr_pfn, last_pfn; 84 85 last_pfn = (sp_banks[0].base_addr + sp_banks[0].num_bytes) >> PAGE_SHIFT; 86 for (i = 1; sp_banks[i].num_bytes != 0; i++) { 87 curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT; 88 89 if (curr_pfn >= tmp) { 90 if (last_pfn < tmp) 91 tmp = last_pfn; 92 break; 93 } 94 95 last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT; 96 } 97 98 return tmp; 99 } 100 101 static void __init find_ramdisk(unsigned long end_of_phys_memory) 102 { 103 #ifdef CONFIG_BLK_DEV_INITRD 104 unsigned long size; 105 106 /* Now have to check initial ramdisk, so that it won't pass 107 * the end of memory 108 */ 109 if (sparc_ramdisk_image) { 110 if (sparc_ramdisk_image >= (unsigned long)&_end - 2 * PAGE_SIZE) 111 sparc_ramdisk_image -= KERNBASE; 112 initrd_start = sparc_ramdisk_image + phys_base; 113 initrd_end = initrd_start + sparc_ramdisk_size; 114 if (initrd_end > end_of_phys_memory) { 115 printk(KERN_CRIT "initrd extends beyond end of memory " 116 "(0x%016lx > 0x%016lx)\ndisabling initrd\n", 117 initrd_end, end_of_phys_memory); 118 initrd_start = 0; 119 } else { 120 /* Reserve the initrd image area. */ 121 size = initrd_end - initrd_start; 122 memblock_reserve(initrd_start, size); 123 124 initrd_start = (initrd_start - phys_base) + PAGE_OFFSET; 125 initrd_end = (initrd_end - phys_base) + PAGE_OFFSET; 126 } 127 } 128 #endif 129 } 130 131 unsigned long __init bootmem_init(unsigned long *pages_avail) 132 { 133 unsigned long start_pfn, bytes_avail, size; 134 unsigned long end_of_phys_memory = 0; 135 unsigned long high_pages = 0; 136 int i; 137 138 memblock_set_bottom_up(true); 139 memblock_allow_resize(); 140 141 bytes_avail = 0UL; 142 for (i = 0; sp_banks[i].num_bytes != 0; i++) { 143 end_of_phys_memory = sp_banks[i].base_addr + 144 sp_banks[i].num_bytes; 145 bytes_avail += sp_banks[i].num_bytes; 146 if (cmdline_memory_size) { 147 if (bytes_avail > cmdline_memory_size) { 148 unsigned long slack = bytes_avail - cmdline_memory_size; 149 150 bytes_avail -= slack; 151 end_of_phys_memory -= slack; 152 153 sp_banks[i].num_bytes -= slack; 154 if (sp_banks[i].num_bytes == 0) { 155 sp_banks[i].base_addr = 0xdeadbeef; 156 } else { 157 memblock_add(sp_banks[i].base_addr, 158 sp_banks[i].num_bytes); 159 sp_banks[i+1].num_bytes = 0; 160 sp_banks[i+1].base_addr = 0xdeadbeef; 161 } 162 break; 163 } 164 } 165 memblock_add(sp_banks[i].base_addr, sp_banks[i].num_bytes); 166 } 167 168 /* Start with page aligned address of last symbol in kernel 169 * image. 170 */ 171 start_pfn = (unsigned long)__pa(PAGE_ALIGN((unsigned long) &_end)); 172 173 /* Now shift down to get the real physical page frame number. */ 174 start_pfn >>= PAGE_SHIFT; 175 176 max_pfn = end_of_phys_memory >> PAGE_SHIFT; 177 178 max_low_pfn = max_pfn; 179 highstart_pfn = highend_pfn = max_pfn; 180 181 if (max_low_pfn > pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT)) { 182 highstart_pfn = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT); 183 max_low_pfn = calc_max_low_pfn(); 184 high_pages = calc_highpages(); 185 printk(KERN_NOTICE "%ldMB HIGHMEM available.\n", 186 high_pages >> (20 - PAGE_SHIFT)); 187 } 188 189 find_ramdisk(end_of_phys_memory); 190 191 /* Reserve the kernel text/data/bss. */ 192 size = (start_pfn << PAGE_SHIFT) - phys_base; 193 memblock_reserve(phys_base, size); 194 memblock_add(phys_base, size); 195 196 size = memblock_phys_mem_size() - memblock_reserved_size(); 197 *pages_avail = (size >> PAGE_SHIFT) - high_pages; 198 199 /* Only allow low memory to be allocated via memblock allocation */ 200 memblock_set_current_limit(max_low_pfn << PAGE_SHIFT); 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 */ 210 void __init paging_init(void) 211 { 212 srmmu_paging_init(); 213 prom_build_devicetree(); 214 of_fill_in_cpu_data(); 215 device_scan(); 216 } 217 218 static 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 } 234 235 static 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 } 246 247 void __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 memblock_alloc(i << 2, SMP_CACHE_BYTES); 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 memblock_free_all(); 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 } 295 296 void sparc_flush_page_to_ram(struct page *page) 297 { 298 unsigned long vaddr = (unsigned long)page_address(page); 299 300 __flush_page_to_ram(vaddr); 301 } 302 EXPORT_SYMBOL(sparc_flush_page_to_ram); 303 304 void sparc_flush_folio_to_ram(struct folio *folio) 305 { 306 unsigned long vaddr = (unsigned long)folio_address(folio); 307 unsigned int i, nr = folio_nr_pages(folio); 308 309 for (i = 0; i < nr; i++) 310 __flush_page_to_ram(vaddr + i * PAGE_SIZE); 311 } 312 EXPORT_SYMBOL(sparc_flush_folio_to_ram); 313 314 static const pgprot_t protection_map[16] = { 315 [VM_NONE] = PAGE_NONE, 316 [VM_READ] = PAGE_READONLY, 317 [VM_WRITE] = PAGE_COPY, 318 [VM_WRITE | VM_READ] = PAGE_COPY, 319 [VM_EXEC] = PAGE_READONLY, 320 [VM_EXEC | VM_READ] = PAGE_READONLY, 321 [VM_EXEC | VM_WRITE] = PAGE_COPY, 322 [VM_EXEC | VM_WRITE | VM_READ] = PAGE_COPY, 323 [VM_SHARED] = PAGE_NONE, 324 [VM_SHARED | VM_READ] = PAGE_READONLY, 325 [VM_SHARED | VM_WRITE] = PAGE_SHARED, 326 [VM_SHARED | VM_WRITE | VM_READ] = PAGE_SHARED, 327 [VM_SHARED | VM_EXEC] = PAGE_READONLY, 328 [VM_SHARED | VM_EXEC | VM_READ] = PAGE_READONLY, 329 [VM_SHARED | VM_EXEC | VM_WRITE] = PAGE_SHARED, 330 [VM_SHARED | VM_EXEC | VM_WRITE | VM_READ] = PAGE_SHARED 331 }; 332 DECLARE_VM_GET_PAGE_PROT 333