1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Based on arch/arm/kernel/setup.c 4 * 5 * Copyright (C) 1995-2001 Russell King 6 * Copyright (C) 2012 ARM Ltd. 7 */ 8 9 #include <linux/acpi.h> 10 #include <linux/export.h> 11 #include <linux/kernel.h> 12 #include <linux/stddef.h> 13 #include <linux/ioport.h> 14 #include <linux/delay.h> 15 #include <linux/initrd.h> 16 #include <linux/console.h> 17 #include <linux/cache.h> 18 #include <linux/screen_info.h> 19 #include <linux/init.h> 20 #include <linux/kexec.h> 21 #include <linux/root_dev.h> 22 #include <linux/cpu.h> 23 #include <linux/interrupt.h> 24 #include <linux/smp.h> 25 #include <linux/fs.h> 26 #include <linux/proc_fs.h> 27 #include <linux/memblock.h> 28 #include <linux/of_fdt.h> 29 #include <linux/efi.h> 30 #include <linux/psci.h> 31 #include <linux/sched/task.h> 32 #include <linux/mm.h> 33 34 #include <asm/acpi.h> 35 #include <asm/fixmap.h> 36 #include <asm/cpu.h> 37 #include <asm/cputype.h> 38 #include <asm/daifflags.h> 39 #include <asm/elf.h> 40 #include <asm/cpufeature.h> 41 #include <asm/cpu_ops.h> 42 #include <asm/kasan.h> 43 #include <asm/numa.h> 44 #include <asm/sections.h> 45 #include <asm/setup.h> 46 #include <asm/smp_plat.h> 47 #include <asm/cacheflush.h> 48 #include <asm/tlbflush.h> 49 #include <asm/traps.h> 50 #include <asm/efi.h> 51 #include <asm/xen/hypervisor.h> 52 #include <asm/mmu_context.h> 53 54 static int num_standard_resources; 55 static struct resource *standard_resources; 56 57 phys_addr_t __fdt_pointer __initdata; 58 59 /* 60 * Standard memory resources 61 */ 62 static struct resource mem_res[] = { 63 { 64 .name = "Kernel code", 65 .start = 0, 66 .end = 0, 67 .flags = IORESOURCE_SYSTEM_RAM 68 }, 69 { 70 .name = "Kernel data", 71 .start = 0, 72 .end = 0, 73 .flags = IORESOURCE_SYSTEM_RAM 74 } 75 }; 76 77 #define kernel_code mem_res[0] 78 #define kernel_data mem_res[1] 79 80 /* 81 * The recorded values of x0 .. x3 upon kernel entry. 82 */ 83 u64 __cacheline_aligned boot_args[4]; 84 85 void __init smp_setup_processor_id(void) 86 { 87 u64 mpidr = read_cpuid_mpidr() & MPIDR_HWID_BITMASK; 88 set_cpu_logical_map(0, mpidr); 89 90 /* 91 * clear __my_cpu_offset on boot CPU to avoid hang caused by 92 * using percpu variable early, for example, lockdep will 93 * access percpu variable inside lock_release 94 */ 95 set_my_cpu_offset(0); 96 pr_info("Booting Linux on physical CPU 0x%010lx [0x%08x]\n", 97 (unsigned long)mpidr, read_cpuid_id()); 98 } 99 100 bool arch_match_cpu_phys_id(int cpu, u64 phys_id) 101 { 102 return phys_id == cpu_logical_map(cpu); 103 } 104 105 struct mpidr_hash mpidr_hash; 106 /** 107 * smp_build_mpidr_hash - Pre-compute shifts required at each affinity 108 * level in order to build a linear index from an 109 * MPIDR value. Resulting algorithm is a collision 110 * free hash carried out through shifting and ORing 111 */ 112 static void __init smp_build_mpidr_hash(void) 113 { 114 u32 i, affinity, fs[4], bits[4], ls; 115 u64 mask = 0; 116 /* 117 * Pre-scan the list of MPIDRS and filter out bits that do 118 * not contribute to affinity levels, ie they never toggle. 119 */ 120 for_each_possible_cpu(i) 121 mask |= (cpu_logical_map(i) ^ cpu_logical_map(0)); 122 pr_debug("mask of set bits %#llx\n", mask); 123 /* 124 * Find and stash the last and first bit set at all affinity levels to 125 * check how many bits are required to represent them. 126 */ 127 for (i = 0; i < 4; i++) { 128 affinity = MPIDR_AFFINITY_LEVEL(mask, i); 129 /* 130 * Find the MSB bit and LSB bits position 131 * to determine how many bits are required 132 * to express the affinity level. 133 */ 134 ls = fls(affinity); 135 fs[i] = affinity ? ffs(affinity) - 1 : 0; 136 bits[i] = ls - fs[i]; 137 } 138 /* 139 * An index can be created from the MPIDR_EL1 by isolating the 140 * significant bits at each affinity level and by shifting 141 * them in order to compress the 32 bits values space to a 142 * compressed set of values. This is equivalent to hashing 143 * the MPIDR_EL1 through shifting and ORing. It is a collision free 144 * hash though not minimal since some levels might contain a number 145 * of CPUs that is not an exact power of 2 and their bit 146 * representation might contain holes, eg MPIDR_EL1[7:0] = {0x2, 0x80}. 147 */ 148 mpidr_hash.shift_aff[0] = MPIDR_LEVEL_SHIFT(0) + fs[0]; 149 mpidr_hash.shift_aff[1] = MPIDR_LEVEL_SHIFT(1) + fs[1] - bits[0]; 150 mpidr_hash.shift_aff[2] = MPIDR_LEVEL_SHIFT(2) + fs[2] - 151 (bits[1] + bits[0]); 152 mpidr_hash.shift_aff[3] = MPIDR_LEVEL_SHIFT(3) + 153 fs[3] - (bits[2] + bits[1] + bits[0]); 154 mpidr_hash.mask = mask; 155 mpidr_hash.bits = bits[3] + bits[2] + bits[1] + bits[0]; 156 pr_debug("MPIDR hash: aff0[%u] aff1[%u] aff2[%u] aff3[%u] mask[%#llx] bits[%u]\n", 157 mpidr_hash.shift_aff[0], 158 mpidr_hash.shift_aff[1], 159 mpidr_hash.shift_aff[2], 160 mpidr_hash.shift_aff[3], 161 mpidr_hash.mask, 162 mpidr_hash.bits); 163 /* 164 * 4x is an arbitrary value used to warn on a hash table much bigger 165 * than expected on most systems. 166 */ 167 if (mpidr_hash_size() > 4 * num_possible_cpus()) 168 pr_warn("Large number of MPIDR hash buckets detected\n"); 169 } 170 171 static void *early_fdt_ptr __initdata; 172 173 void __init *get_early_fdt_ptr(void) 174 { 175 return early_fdt_ptr; 176 } 177 178 asmlinkage void __init early_fdt_map(u64 dt_phys) 179 { 180 int fdt_size; 181 182 early_fixmap_init(); 183 early_fdt_ptr = fixmap_remap_fdt(dt_phys, &fdt_size, PAGE_KERNEL); 184 } 185 186 static void __init setup_machine_fdt(phys_addr_t dt_phys) 187 { 188 int size; 189 void *dt_virt = fixmap_remap_fdt(dt_phys, &size, PAGE_KERNEL); 190 const char *name; 191 192 if (dt_virt) 193 memblock_reserve(dt_phys, size); 194 195 if (!dt_virt || !early_init_dt_scan(dt_virt)) { 196 pr_crit("\n" 197 "Error: invalid device tree blob at physical address %pa (virtual address 0x%p)\n" 198 "The dtb must be 8-byte aligned and must not exceed 2 MB in size\n" 199 "\nPlease check your bootloader.", 200 &dt_phys, dt_virt); 201 202 while (true) 203 cpu_relax(); 204 } 205 206 /* Early fixups are done, map the FDT as read-only now */ 207 fixmap_remap_fdt(dt_phys, &size, PAGE_KERNEL_RO); 208 209 name = of_flat_dt_get_machine_name(); 210 if (!name) 211 return; 212 213 pr_info("Machine model: %s\n", name); 214 dump_stack_set_arch_desc("%s (DT)", name); 215 } 216 217 static void __init request_standard_resources(void) 218 { 219 struct memblock_region *region; 220 struct resource *res; 221 unsigned long i = 0; 222 size_t res_size; 223 224 kernel_code.start = __pa_symbol(_stext); 225 kernel_code.end = __pa_symbol(__init_begin - 1); 226 kernel_data.start = __pa_symbol(_sdata); 227 kernel_data.end = __pa_symbol(_end - 1); 228 229 num_standard_resources = memblock.memory.cnt; 230 res_size = num_standard_resources * sizeof(*standard_resources); 231 standard_resources = memblock_alloc(res_size, SMP_CACHE_BYTES); 232 if (!standard_resources) 233 panic("%s: Failed to allocate %zu bytes\n", __func__, res_size); 234 235 for_each_mem_region(region) { 236 res = &standard_resources[i++]; 237 if (memblock_is_nomap(region)) { 238 res->name = "reserved"; 239 res->flags = IORESOURCE_MEM; 240 } else { 241 res->name = "System RAM"; 242 res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; 243 } 244 res->start = __pfn_to_phys(memblock_region_memory_base_pfn(region)); 245 res->end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1; 246 247 request_resource(&iomem_resource, res); 248 249 if (kernel_code.start >= res->start && 250 kernel_code.end <= res->end) 251 request_resource(res, &kernel_code); 252 if (kernel_data.start >= res->start && 253 kernel_data.end <= res->end) 254 request_resource(res, &kernel_data); 255 #ifdef CONFIG_KEXEC_CORE 256 /* Userspace will find "Crash kernel" region in /proc/iomem. */ 257 if (crashk_res.end && crashk_res.start >= res->start && 258 crashk_res.end <= res->end) 259 request_resource(res, &crashk_res); 260 #endif 261 } 262 } 263 264 static int __init reserve_memblock_reserved_regions(void) 265 { 266 u64 i, j; 267 268 for (i = 0; i < num_standard_resources; ++i) { 269 struct resource *mem = &standard_resources[i]; 270 phys_addr_t r_start, r_end, mem_size = resource_size(mem); 271 272 if (!memblock_is_region_reserved(mem->start, mem_size)) 273 continue; 274 275 for_each_reserved_mem_range(j, &r_start, &r_end) { 276 resource_size_t start, end; 277 278 start = max(PFN_PHYS(PFN_DOWN(r_start)), mem->start); 279 end = min(PFN_PHYS(PFN_UP(r_end)) - 1, mem->end); 280 281 if (start > mem->end || end < mem->start) 282 continue; 283 284 reserve_region_with_split(mem, start, end, "reserved"); 285 } 286 } 287 288 return 0; 289 } 290 arch_initcall(reserve_memblock_reserved_regions); 291 292 u64 __cpu_logical_map[NR_CPUS] = { [0 ... NR_CPUS-1] = INVALID_HWID }; 293 294 u64 cpu_logical_map(unsigned int cpu) 295 { 296 return __cpu_logical_map[cpu]; 297 } 298 299 void __init __no_sanitize_address setup_arch(char **cmdline_p) 300 { 301 init_mm.start_code = (unsigned long) _stext; 302 init_mm.end_code = (unsigned long) _etext; 303 init_mm.end_data = (unsigned long) _edata; 304 init_mm.brk = (unsigned long) _end; 305 306 *cmdline_p = boot_command_line; 307 308 /* 309 * If know now we are going to need KPTI then use non-global 310 * mappings from the start, avoiding the cost of rewriting 311 * everything later. 312 */ 313 arm64_use_ng_mappings = kaslr_requires_kpti(); 314 315 early_fixmap_init(); 316 early_ioremap_init(); 317 318 setup_machine_fdt(__fdt_pointer); 319 320 /* 321 * Initialise the static keys early as they may be enabled by the 322 * cpufeature code and early parameters. 323 */ 324 jump_label_init(); 325 parse_early_param(); 326 327 /* 328 * Unmask asynchronous aborts and fiq after bringing up possible 329 * earlycon. (Report possible System Errors once we can report this 330 * occurred). 331 */ 332 local_daif_restore(DAIF_PROCCTX_NOIRQ); 333 334 /* 335 * TTBR0 is only used for the identity mapping at this stage. Make it 336 * point to zero page to avoid speculatively fetching new entries. 337 */ 338 cpu_uninstall_idmap(); 339 340 xen_early_init(); 341 efi_init(); 342 343 if (!efi_enabled(EFI_BOOT) && ((u64)_text % MIN_KIMG_ALIGN) != 0) 344 pr_warn(FW_BUG "Kernel image misaligned at boot, please fix your bootloader!"); 345 346 arm64_memblock_init(); 347 348 paging_init(); 349 350 acpi_table_upgrade(); 351 352 /* Parse the ACPI tables for possible boot-time configuration */ 353 acpi_boot_table_init(); 354 355 if (acpi_disabled) 356 unflatten_device_tree(); 357 358 bootmem_init(); 359 360 kasan_init(); 361 362 request_standard_resources(); 363 364 early_ioremap_reset(); 365 366 if (acpi_disabled) 367 psci_dt_init(); 368 else 369 psci_acpi_init(); 370 371 init_bootcpu_ops(); 372 smp_init_cpus(); 373 smp_build_mpidr_hash(); 374 375 /* Init percpu seeds for random tags after cpus are set up. */ 376 kasan_init_sw_tags(); 377 378 #ifdef CONFIG_ARM64_SW_TTBR0_PAN 379 /* 380 * Make sure init_thread_info.ttbr0 always generates translation 381 * faults in case uaccess_enable() is inadvertently called by the init 382 * thread. 383 */ 384 init_task.thread_info.ttbr0 = __pa_symbol(reserved_pg_dir); 385 #endif 386 387 if (boot_args[1] || boot_args[2] || boot_args[3]) { 388 pr_err("WARNING: x1-x3 nonzero in violation of boot protocol:\n" 389 "\tx1: %016llx\n\tx2: %016llx\n\tx3: %016llx\n" 390 "This indicates a broken bootloader or old kernel\n", 391 boot_args[1], boot_args[2], boot_args[3]); 392 } 393 } 394 395 static inline bool cpu_can_disable(unsigned int cpu) 396 { 397 #ifdef CONFIG_HOTPLUG_CPU 398 const struct cpu_operations *ops = get_cpu_ops(cpu); 399 400 if (ops && ops->cpu_can_disable) 401 return ops->cpu_can_disable(cpu); 402 #endif 403 return false; 404 } 405 406 static int __init topology_init(void) 407 { 408 int i; 409 410 for_each_online_node(i) 411 register_one_node(i); 412 413 for_each_possible_cpu(i) { 414 struct cpu *cpu = &per_cpu(cpu_data.cpu, i); 415 cpu->hotpluggable = cpu_can_disable(i); 416 register_cpu(cpu, i); 417 } 418 419 return 0; 420 } 421 subsys_initcall(topology_init); 422 423 static void dump_kernel_offset(void) 424 { 425 const unsigned long offset = kaslr_offset(); 426 427 if (IS_ENABLED(CONFIG_RANDOMIZE_BASE) && offset > 0) { 428 pr_emerg("Kernel Offset: 0x%lx from 0x%lx\n", 429 offset, KIMAGE_VADDR); 430 pr_emerg("PHYS_OFFSET: 0x%llx\n", PHYS_OFFSET); 431 } else { 432 pr_emerg("Kernel Offset: disabled\n"); 433 } 434 } 435 436 static int arm64_panic_block_dump(struct notifier_block *self, 437 unsigned long v, void *p) 438 { 439 dump_kernel_offset(); 440 dump_cpu_features(); 441 dump_mem_limit(); 442 return 0; 443 } 444 445 static struct notifier_block arm64_panic_block = { 446 .notifier_call = arm64_panic_block_dump 447 }; 448 449 static int __init register_arm64_panic_block(void) 450 { 451 atomic_notifier_chain_register(&panic_notifier_list, 452 &arm64_panic_block); 453 return 0; 454 } 455 device_initcall(register_arm64_panic_block); 456