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