1 /* 2 * Based on arch/arm/kernel/setup.c 3 * 4 * Copyright (C) 1995-2001 Russell King 5 * Copyright (C) 2012 ARM Ltd. 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License version 2 as 9 * published by the Free Software Foundation. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program. If not, see <http://www.gnu.org/licenses/>. 18 */ 19 20 #include <linux/acpi.h> 21 #include <linux/export.h> 22 #include <linux/kernel.h> 23 #include <linux/stddef.h> 24 #include <linux/ioport.h> 25 #include <linux/delay.h> 26 #include <linux/utsname.h> 27 #include <linux/initrd.h> 28 #include <linux/console.h> 29 #include <linux/cache.h> 30 #include <linux/bootmem.h> 31 #include <linux/screen_info.h> 32 #include <linux/init.h> 33 #include <linux/kexec.h> 34 #include <linux/crash_dump.h> 35 #include <linux/root_dev.h> 36 #include <linux/cpu.h> 37 #include <linux/interrupt.h> 38 #include <linux/smp.h> 39 #include <linux/fs.h> 40 #include <linux/proc_fs.h> 41 #include <linux/memblock.h> 42 #include <linux/of_iommu.h> 43 #include <linux/of_fdt.h> 44 #include <linux/of_platform.h> 45 #include <linux/efi.h> 46 #include <linux/psci.h> 47 48 #include <asm/acpi.h> 49 #include <asm/fixmap.h> 50 #include <asm/cpu.h> 51 #include <asm/cputype.h> 52 #include <asm/elf.h> 53 #include <asm/cpufeature.h> 54 #include <asm/cpu_ops.h> 55 #include <asm/kasan.h> 56 #include <asm/sections.h> 57 #include <asm/setup.h> 58 #include <asm/smp_plat.h> 59 #include <asm/cacheflush.h> 60 #include <asm/tlbflush.h> 61 #include <asm/traps.h> 62 #include <asm/memblock.h> 63 #include <asm/efi.h> 64 #include <asm/xen/hypervisor.h> 65 #include <asm/mmu_context.h> 66 67 phys_addr_t __fdt_pointer __initdata; 68 69 /* 70 * Standard memory resources 71 */ 72 static struct resource mem_res[] = { 73 { 74 .name = "Kernel code", 75 .start = 0, 76 .end = 0, 77 .flags = IORESOURCE_SYSTEM_RAM 78 }, 79 { 80 .name = "Kernel data", 81 .start = 0, 82 .end = 0, 83 .flags = IORESOURCE_SYSTEM_RAM 84 } 85 }; 86 87 #define kernel_code mem_res[0] 88 #define kernel_data mem_res[1] 89 90 /* 91 * The recorded values of x0 .. x3 upon kernel entry. 92 */ 93 u64 __cacheline_aligned boot_args[4]; 94 95 void __init smp_setup_processor_id(void) 96 { 97 u64 mpidr = read_cpuid_mpidr() & MPIDR_HWID_BITMASK; 98 cpu_logical_map(0) = mpidr; 99 100 /* 101 * clear __my_cpu_offset on boot CPU to avoid hang caused by 102 * using percpu variable early, for example, lockdep will 103 * access percpu variable inside lock_release 104 */ 105 set_my_cpu_offset(0); 106 pr_info("Booting Linux on physical CPU 0x%lx\n", (unsigned long)mpidr); 107 } 108 109 bool arch_match_cpu_phys_id(int cpu, u64 phys_id) 110 { 111 return phys_id == cpu_logical_map(cpu); 112 } 113 114 struct mpidr_hash mpidr_hash; 115 /** 116 * smp_build_mpidr_hash - Pre-compute shifts required at each affinity 117 * level in order to build a linear index from an 118 * MPIDR value. Resulting algorithm is a collision 119 * free hash carried out through shifting and ORing 120 */ 121 static void __init smp_build_mpidr_hash(void) 122 { 123 u32 i, affinity, fs[4], bits[4], ls; 124 u64 mask = 0; 125 /* 126 * Pre-scan the list of MPIDRS and filter out bits that do 127 * not contribute to affinity levels, ie they never toggle. 128 */ 129 for_each_possible_cpu(i) 130 mask |= (cpu_logical_map(i) ^ cpu_logical_map(0)); 131 pr_debug("mask of set bits %#llx\n", mask); 132 /* 133 * Find and stash the last and first bit set at all affinity levels to 134 * check how many bits are required to represent them. 135 */ 136 for (i = 0; i < 4; i++) { 137 affinity = MPIDR_AFFINITY_LEVEL(mask, i); 138 /* 139 * Find the MSB bit and LSB bits position 140 * to determine how many bits are required 141 * to express the affinity level. 142 */ 143 ls = fls(affinity); 144 fs[i] = affinity ? ffs(affinity) - 1 : 0; 145 bits[i] = ls - fs[i]; 146 } 147 /* 148 * An index can be created from the MPIDR_EL1 by isolating the 149 * significant bits at each affinity level and by shifting 150 * them in order to compress the 32 bits values space to a 151 * compressed set of values. This is equivalent to hashing 152 * the MPIDR_EL1 through shifting and ORing. It is a collision free 153 * hash though not minimal since some levels might contain a number 154 * of CPUs that is not an exact power of 2 and their bit 155 * representation might contain holes, eg MPIDR_EL1[7:0] = {0x2, 0x80}. 156 */ 157 mpidr_hash.shift_aff[0] = MPIDR_LEVEL_SHIFT(0) + fs[0]; 158 mpidr_hash.shift_aff[1] = MPIDR_LEVEL_SHIFT(1) + fs[1] - bits[0]; 159 mpidr_hash.shift_aff[2] = MPIDR_LEVEL_SHIFT(2) + fs[2] - 160 (bits[1] + bits[0]); 161 mpidr_hash.shift_aff[3] = MPIDR_LEVEL_SHIFT(3) + 162 fs[3] - (bits[2] + bits[1] + bits[0]); 163 mpidr_hash.mask = mask; 164 mpidr_hash.bits = bits[3] + bits[2] + bits[1] + bits[0]; 165 pr_debug("MPIDR hash: aff0[%u] aff1[%u] aff2[%u] aff3[%u] mask[%#llx] bits[%u]\n", 166 mpidr_hash.shift_aff[0], 167 mpidr_hash.shift_aff[1], 168 mpidr_hash.shift_aff[2], 169 mpidr_hash.shift_aff[3], 170 mpidr_hash.mask, 171 mpidr_hash.bits); 172 /* 173 * 4x is an arbitrary value used to warn on a hash table much bigger 174 * than expected on most systems. 175 */ 176 if (mpidr_hash_size() > 4 * num_possible_cpus()) 177 pr_warn("Large number of MPIDR hash buckets detected\n"); 178 __flush_dcache_area(&mpidr_hash, sizeof(struct mpidr_hash)); 179 } 180 181 static void __init setup_machine_fdt(phys_addr_t dt_phys) 182 { 183 void *dt_virt = fixmap_remap_fdt(dt_phys); 184 185 if (!dt_virt || !early_init_dt_scan(dt_virt)) { 186 pr_crit("\n" 187 "Error: invalid device tree blob at physical address %pa (virtual address 0x%p)\n" 188 "The dtb must be 8-byte aligned and must not exceed 2 MB in size\n" 189 "\nPlease check your bootloader.", 190 &dt_phys, dt_virt); 191 192 while (true) 193 cpu_relax(); 194 } 195 196 dump_stack_set_arch_desc("%s (DT)", of_flat_dt_get_machine_name()); 197 } 198 199 static void __init request_standard_resources(void) 200 { 201 struct memblock_region *region; 202 struct resource *res; 203 204 kernel_code.start = virt_to_phys(_text); 205 kernel_code.end = virt_to_phys(_etext - 1); 206 kernel_data.start = virt_to_phys(_sdata); 207 kernel_data.end = virt_to_phys(_end - 1); 208 209 for_each_memblock(memory, region) { 210 res = alloc_bootmem_low(sizeof(*res)); 211 res->name = "System RAM"; 212 res->start = __pfn_to_phys(memblock_region_memory_base_pfn(region)); 213 res->end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1; 214 res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; 215 216 request_resource(&iomem_resource, res); 217 218 if (kernel_code.start >= res->start && 219 kernel_code.end <= res->end) 220 request_resource(res, &kernel_code); 221 if (kernel_data.start >= res->start && 222 kernel_data.end <= res->end) 223 request_resource(res, &kernel_data); 224 } 225 } 226 227 #ifdef CONFIG_BLK_DEV_INITRD 228 /* 229 * Relocate initrd if it is not completely within the linear mapping. 230 * This would be the case if mem= cuts out all or part of it. 231 */ 232 static void __init relocate_initrd(void) 233 { 234 phys_addr_t orig_start = __virt_to_phys(initrd_start); 235 phys_addr_t orig_end = __virt_to_phys(initrd_end); 236 phys_addr_t ram_end = memblock_end_of_DRAM(); 237 phys_addr_t new_start; 238 unsigned long size, to_free = 0; 239 void *dest; 240 241 if (orig_end <= ram_end) 242 return; 243 244 /* 245 * Any of the original initrd which overlaps the linear map should 246 * be freed after relocating. 247 */ 248 if (orig_start < ram_end) 249 to_free = ram_end - orig_start; 250 251 size = orig_end - orig_start; 252 if (!size) 253 return; 254 255 /* initrd needs to be relocated completely inside linear mapping */ 256 new_start = memblock_find_in_range(0, PFN_PHYS(max_pfn), 257 size, PAGE_SIZE); 258 if (!new_start) 259 panic("Cannot relocate initrd of size %ld\n", size); 260 memblock_reserve(new_start, size); 261 262 initrd_start = __phys_to_virt(new_start); 263 initrd_end = initrd_start + size; 264 265 pr_info("Moving initrd from [%llx-%llx] to [%llx-%llx]\n", 266 orig_start, orig_start + size - 1, 267 new_start, new_start + size - 1); 268 269 dest = (void *)initrd_start; 270 271 if (to_free) { 272 memcpy(dest, (void *)__phys_to_virt(orig_start), to_free); 273 dest += to_free; 274 } 275 276 copy_from_early_mem(dest, orig_start + to_free, size - to_free); 277 278 if (to_free) { 279 pr_info("Freeing original RAMDISK from [%llx-%llx]\n", 280 orig_start, orig_start + to_free - 1); 281 memblock_free(orig_start, to_free); 282 } 283 } 284 #else 285 static inline void __init relocate_initrd(void) 286 { 287 } 288 #endif 289 290 u64 __cpu_logical_map[NR_CPUS] = { [0 ... NR_CPUS-1] = INVALID_HWID }; 291 292 void __init setup_arch(char **cmdline_p) 293 { 294 pr_info("Boot CPU: AArch64 Processor [%08x]\n", read_cpuid_id()); 295 296 sprintf(init_utsname()->machine, ELF_PLATFORM); 297 init_mm.start_code = (unsigned long) _text; 298 init_mm.end_code = (unsigned long) _etext; 299 init_mm.end_data = (unsigned long) _edata; 300 init_mm.brk = (unsigned long) _end; 301 302 *cmdline_p = boot_command_line; 303 304 early_fixmap_init(); 305 early_ioremap_init(); 306 307 setup_machine_fdt(__fdt_pointer); 308 309 parse_early_param(); 310 311 /* 312 * Unmask asynchronous aborts after bringing up possible earlycon. 313 * (Report possible System Errors once we can report this occurred) 314 */ 315 local_async_enable(); 316 317 /* 318 * TTBR0 is only used for the identity mapping at this stage. Make it 319 * point to zero page to avoid speculatively fetching new entries. 320 */ 321 cpu_uninstall_idmap(); 322 323 efi_init(); 324 arm64_memblock_init(); 325 326 /* Parse the ACPI tables for possible boot-time configuration */ 327 acpi_boot_table_init(); 328 329 paging_init(); 330 relocate_initrd(); 331 332 kasan_init(); 333 334 request_standard_resources(); 335 336 early_ioremap_reset(); 337 338 if (acpi_disabled) { 339 unflatten_device_tree(); 340 psci_dt_init(); 341 } else { 342 psci_acpi_init(); 343 } 344 xen_early_init(); 345 346 cpu_read_bootcpu_ops(); 347 smp_init_cpus(); 348 smp_build_mpidr_hash(); 349 350 #ifdef CONFIG_VT 351 #if defined(CONFIG_VGA_CONSOLE) 352 conswitchp = &vga_con; 353 #elif defined(CONFIG_DUMMY_CONSOLE) 354 conswitchp = &dummy_con; 355 #endif 356 #endif 357 if (boot_args[1] || boot_args[2] || boot_args[3]) { 358 pr_err("WARNING: x1-x3 nonzero in violation of boot protocol:\n" 359 "\tx1: %016llx\n\tx2: %016llx\n\tx3: %016llx\n" 360 "This indicates a broken bootloader or old kernel\n", 361 boot_args[1], boot_args[2], boot_args[3]); 362 } 363 } 364 365 static int __init arm64_device_init(void) 366 { 367 if (of_have_populated_dt()) { 368 of_iommu_init(); 369 of_platform_populate(NULL, of_default_bus_match_table, 370 NULL, NULL); 371 } else if (acpi_disabled) { 372 pr_crit("Device tree not populated\n"); 373 } 374 return 0; 375 } 376 arch_initcall_sync(arm64_device_init); 377 378 static int __init topology_init(void) 379 { 380 int i; 381 382 for_each_possible_cpu(i) { 383 struct cpu *cpu = &per_cpu(cpu_data.cpu, i); 384 cpu->hotpluggable = 1; 385 register_cpu(cpu, i); 386 } 387 388 return 0; 389 } 390 subsys_initcall(topology_init); 391 392 /* 393 * Dump out kernel offset information on panic. 394 */ 395 static int dump_kernel_offset(struct notifier_block *self, unsigned long v, 396 void *p) 397 { 398 u64 const kaslr_offset = kimage_vaddr - KIMAGE_VADDR; 399 400 if (IS_ENABLED(CONFIG_RANDOMIZE_BASE) && kaslr_offset > 0) { 401 pr_emerg("Kernel Offset: 0x%llx from 0x%lx\n", 402 kaslr_offset, KIMAGE_VADDR); 403 } else { 404 pr_emerg("Kernel Offset: disabled\n"); 405 } 406 return 0; 407 } 408 409 static struct notifier_block kernel_offset_notifier = { 410 .notifier_call = dump_kernel_offset 411 }; 412 413 static int __init register_kernel_offset_dumper(void) 414 { 415 atomic_notifier_chain_register(&panic_notifier_list, 416 &kernel_offset_notifier); 417 return 0; 418 } 419 __initcall(register_kernel_offset_dumper); 420