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