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/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 static void __init find_ramdisk(unsigned long end_of_phys_memory) 105 { 106 #ifdef CONFIG_BLK_DEV_INITRD 107 unsigned long size; 108 109 /* Now have to check initial ramdisk, so that it won't pass 110 * the end of memory 111 */ 112 if (sparc_ramdisk_image) { 113 if (sparc_ramdisk_image >= (unsigned long)&_end - 2 * PAGE_SIZE) 114 sparc_ramdisk_image -= KERNBASE; 115 initrd_start = sparc_ramdisk_image + phys_base; 116 initrd_end = initrd_start + sparc_ramdisk_size; 117 if (initrd_end > end_of_phys_memory) { 118 printk(KERN_CRIT "initrd extends beyond end of memory " 119 "(0x%016lx > 0x%016lx)\ndisabling initrd\n", 120 initrd_end, end_of_phys_memory); 121 initrd_start = 0; 122 } else { 123 /* Reserve the initrd image area. */ 124 size = initrd_end - initrd_start; 125 memblock_reserve(initrd_start, size); 126 127 initrd_start = (initrd_start - phys_base) + PAGE_OFFSET; 128 initrd_end = (initrd_end - phys_base) + PAGE_OFFSET; 129 } 130 } 131 #endif 132 } 133 134 unsigned long __init bootmem_init(unsigned long *pages_avail) 135 { 136 unsigned long start_pfn, bytes_avail, size; 137 unsigned long end_of_phys_memory = 0; 138 unsigned long high_pages = 0; 139 int i; 140 141 memblock_set_bottom_up(true); 142 memblock_allow_resize(); 143 144 bytes_avail = 0UL; 145 for (i = 0; sp_banks[i].num_bytes != 0; i++) { 146 end_of_phys_memory = sp_banks[i].base_addr + 147 sp_banks[i].num_bytes; 148 bytes_avail += sp_banks[i].num_bytes; 149 if (cmdline_memory_size) { 150 if (bytes_avail > cmdline_memory_size) { 151 unsigned long slack = bytes_avail - cmdline_memory_size; 152 153 bytes_avail -= slack; 154 end_of_phys_memory -= slack; 155 156 sp_banks[i].num_bytes -= slack; 157 if (sp_banks[i].num_bytes == 0) { 158 sp_banks[i].base_addr = 0xdeadbeef; 159 } else { 160 memblock_add(sp_banks[i].base_addr, 161 sp_banks[i].num_bytes); 162 sp_banks[i+1].num_bytes = 0; 163 sp_banks[i+1].base_addr = 0xdeadbeef; 164 } 165 break; 166 } 167 } 168 memblock_add(sp_banks[i].base_addr, sp_banks[i].num_bytes); 169 } 170 171 /* Start with page aligned address of last symbol in kernel 172 * image. 173 */ 174 start_pfn = (unsigned long)__pa(PAGE_ALIGN((unsigned long) &_end)); 175 176 /* Now shift down to get the real physical page frame number. */ 177 start_pfn >>= PAGE_SHIFT; 178 179 max_pfn = end_of_phys_memory >> PAGE_SHIFT; 180 181 max_low_pfn = max_pfn; 182 highstart_pfn = highend_pfn = max_pfn; 183 184 if (max_low_pfn > pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT)) { 185 highstart_pfn = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT); 186 max_low_pfn = calc_max_low_pfn(); 187 high_pages = calc_highpages(); 188 printk(KERN_NOTICE "%ldMB HIGHMEM available.\n", 189 high_pages >> (20 - PAGE_SHIFT)); 190 } 191 192 find_ramdisk(end_of_phys_memory); 193 194 /* Reserve the kernel text/data/bss. */ 195 size = (start_pfn << PAGE_SHIFT) - phys_base; 196 memblock_reserve(phys_base, size); 197 198 size = memblock_phys_mem_size() - memblock_reserved_size(); 199 *pages_avail = (size >> PAGE_SHIFT) - high_pages; 200 201 return max_pfn; 202 } 203 204 /* 205 * paging_init() sets up the page tables: We call the MMU specific 206 * init routine based upon the Sun model type on the Sparc. 207 * 208 */ 209 void __init paging_init(void) 210 { 211 srmmu_paging_init(); 212 prom_build_devicetree(); 213 of_fill_in_cpu_data(); 214 device_scan(); 215 } 216 217 static void __init taint_real_pages(void) 218 { 219 int i; 220 221 for (i = 0; sp_banks[i].num_bytes; i++) { 222 unsigned long start, end; 223 224 start = sp_banks[i].base_addr; 225 end = start + sp_banks[i].num_bytes; 226 227 while (start < end) { 228 set_bit(start >> 20, sparc_valid_addr_bitmap); 229 start += PAGE_SIZE; 230 } 231 } 232 } 233 234 static void map_high_region(unsigned long start_pfn, unsigned long end_pfn) 235 { 236 unsigned long tmp; 237 238 #ifdef CONFIG_DEBUG_HIGHMEM 239 printk("mapping high region %08lx - %08lx\n", start_pfn, end_pfn); 240 #endif 241 242 for (tmp = start_pfn; tmp < end_pfn; tmp++) 243 free_highmem_page(pfn_to_page(tmp)); 244 } 245 246 void __init mem_init(void) 247 { 248 int i; 249 250 if (PKMAP_BASE+LAST_PKMAP*PAGE_SIZE >= FIXADDR_START) { 251 prom_printf("BUG: fixmap and pkmap areas overlap\n"); 252 prom_printf("pkbase: 0x%lx pkend: 0x%lx fixstart 0x%lx\n", 253 PKMAP_BASE, 254 (unsigned long)PKMAP_BASE+LAST_PKMAP*PAGE_SIZE, 255 FIXADDR_START); 256 prom_printf("Please mail sparclinux@vger.kernel.org.\n"); 257 prom_halt(); 258 } 259 260 261 /* Saves us work later. */ 262 memset((void *)empty_zero_page, 0, PAGE_SIZE); 263 264 i = last_valid_pfn >> ((20 - PAGE_SHIFT) + 5); 265 i += 1; 266 sparc_valid_addr_bitmap = (unsigned long *) 267 memblock_alloc(i << 2, SMP_CACHE_BYTES); 268 269 if (sparc_valid_addr_bitmap == NULL) { 270 prom_printf("mem_init: Cannot alloc valid_addr_bitmap.\n"); 271 prom_halt(); 272 } 273 memset(sparc_valid_addr_bitmap, 0, i << 2); 274 275 taint_real_pages(); 276 277 max_mapnr = last_valid_pfn - pfn_base; 278 high_memory = __va(max_low_pfn << PAGE_SHIFT); 279 memblock_free_all(); 280 281 for (i = 0; sp_banks[i].num_bytes != 0; i++) { 282 unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT; 283 unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT; 284 285 if (end_pfn <= highstart_pfn) 286 continue; 287 288 if (start_pfn < highstart_pfn) 289 start_pfn = highstart_pfn; 290 291 map_high_region(start_pfn, end_pfn); 292 } 293 294 mem_init_print_info(NULL); 295 } 296 297 void sparc_flush_page_to_ram(struct page *page) 298 { 299 unsigned long vaddr = (unsigned long)page_address(page); 300 301 if (vaddr) 302 __flush_page_to_ram(vaddr); 303 } 304 EXPORT_SYMBOL(sparc_flush_page_to_ram); 305