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 66 phys_addr_t __fdt_pointer __initdata; 67 68 /* 69 * Standard memory resources 70 */ 71 static struct resource mem_res[] = { 72 { 73 .name = "Kernel code", 74 .start = 0, 75 .end = 0, 76 .flags = IORESOURCE_MEM 77 }, 78 { 79 .name = "Kernel data", 80 .start = 0, 81 .end = 0, 82 .flags = IORESOURCE_MEM 83 } 84 }; 85 86 #define kernel_code mem_res[0] 87 #define kernel_data mem_res[1] 88 89 /* 90 * The recorded values of x0 .. x3 upon kernel entry. 91 */ 92 u64 __cacheline_aligned boot_args[4]; 93 94 void __init smp_setup_processor_id(void) 95 { 96 u64 mpidr = read_cpuid_mpidr() & MPIDR_HWID_BITMASK; 97 cpu_logical_map(0) = mpidr; 98 99 /* 100 * clear __my_cpu_offset on boot CPU to avoid hang caused by 101 * using percpu variable early, for example, lockdep will 102 * access percpu variable inside lock_release 103 */ 104 set_my_cpu_offset(0); 105 pr_info("Booting Linux on physical CPU 0x%lx\n", (unsigned long)mpidr); 106 } 107 108 bool arch_match_cpu_phys_id(int cpu, u64 phys_id) 109 { 110 return phys_id == cpu_logical_map(cpu); 111 } 112 113 struct mpidr_hash mpidr_hash; 114 /** 115 * smp_build_mpidr_hash - Pre-compute shifts required at each affinity 116 * level in order to build a linear index from an 117 * MPIDR value. Resulting algorithm is a collision 118 * free hash carried out through shifting and ORing 119 */ 120 static void __init smp_build_mpidr_hash(void) 121 { 122 u32 i, affinity, fs[4], bits[4], ls; 123 u64 mask = 0; 124 /* 125 * Pre-scan the list of MPIDRS and filter out bits that do 126 * not contribute to affinity levels, ie they never toggle. 127 */ 128 for_each_possible_cpu(i) 129 mask |= (cpu_logical_map(i) ^ cpu_logical_map(0)); 130 pr_debug("mask of set bits %#llx\n", mask); 131 /* 132 * Find and stash the last and first bit set at all affinity levels to 133 * check how many bits are required to represent them. 134 */ 135 for (i = 0; i < 4; i++) { 136 affinity = MPIDR_AFFINITY_LEVEL(mask, i); 137 /* 138 * Find the MSB bit and LSB bits position 139 * to determine how many bits are required 140 * to express the affinity level. 141 */ 142 ls = fls(affinity); 143 fs[i] = affinity ? ffs(affinity) - 1 : 0; 144 bits[i] = ls - fs[i]; 145 } 146 /* 147 * An index can be created from the MPIDR_EL1 by isolating the 148 * significant bits at each affinity level and by shifting 149 * them in order to compress the 32 bits values space to a 150 * compressed set of values. This is equivalent to hashing 151 * the MPIDR_EL1 through shifting and ORing. It is a collision free 152 * hash though not minimal since some levels might contain a number 153 * of CPUs that is not an exact power of 2 and their bit 154 * representation might contain holes, eg MPIDR_EL1[7:0] = {0x2, 0x80}. 155 */ 156 mpidr_hash.shift_aff[0] = MPIDR_LEVEL_SHIFT(0) + fs[0]; 157 mpidr_hash.shift_aff[1] = MPIDR_LEVEL_SHIFT(1) + fs[1] - bits[0]; 158 mpidr_hash.shift_aff[2] = MPIDR_LEVEL_SHIFT(2) + fs[2] - 159 (bits[1] + bits[0]); 160 mpidr_hash.shift_aff[3] = MPIDR_LEVEL_SHIFT(3) + 161 fs[3] - (bits[2] + bits[1] + bits[0]); 162 mpidr_hash.mask = mask; 163 mpidr_hash.bits = bits[3] + bits[2] + bits[1] + bits[0]; 164 pr_debug("MPIDR hash: aff0[%u] aff1[%u] aff2[%u] aff3[%u] mask[%#llx] bits[%u]\n", 165 mpidr_hash.shift_aff[0], 166 mpidr_hash.shift_aff[1], 167 mpidr_hash.shift_aff[2], 168 mpidr_hash.shift_aff[3], 169 mpidr_hash.mask, 170 mpidr_hash.bits); 171 /* 172 * 4x is an arbitrary value used to warn on a hash table much bigger 173 * than expected on most systems. 174 */ 175 if (mpidr_hash_size() > 4 * num_possible_cpus()) 176 pr_warn("Large number of MPIDR hash buckets detected\n"); 177 __flush_dcache_area(&mpidr_hash, sizeof(struct mpidr_hash)); 178 } 179 180 static void __init setup_machine_fdt(phys_addr_t dt_phys) 181 { 182 void *dt_virt = fixmap_remap_fdt(dt_phys); 183 184 if (!dt_virt || !early_init_dt_scan(dt_virt)) { 185 pr_crit("\n" 186 "Error: invalid device tree blob at physical address %pa (virtual address 0x%p)\n" 187 "The dtb must be 8-byte aligned and must not exceed 2 MB in size\n" 188 "\nPlease check your bootloader.", 189 &dt_phys, dt_virt); 190 191 while (true) 192 cpu_relax(); 193 } 194 195 dump_stack_set_arch_desc("%s (DT)", of_flat_dt_get_machine_name()); 196 } 197 198 static void __init request_standard_resources(void) 199 { 200 struct memblock_region *region; 201 struct resource *res; 202 203 kernel_code.start = virt_to_phys(_text); 204 kernel_code.end = virt_to_phys(_etext - 1); 205 kernel_data.start = virt_to_phys(_sdata); 206 kernel_data.end = virt_to_phys(_end - 1); 207 208 for_each_memblock(memory, region) { 209 res = alloc_bootmem_low(sizeof(*res)); 210 res->name = "System RAM"; 211 res->start = __pfn_to_phys(memblock_region_memory_base_pfn(region)); 212 res->end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1; 213 res->flags = IORESOURCE_MEM | IORESOURCE_BUSY; 214 215 request_resource(&iomem_resource, res); 216 217 if (kernel_code.start >= res->start && 218 kernel_code.end <= res->end) 219 request_resource(res, &kernel_code); 220 if (kernel_data.start >= res->start && 221 kernel_data.end <= res->end) 222 request_resource(res, &kernel_data); 223 } 224 } 225 226 #ifdef CONFIG_BLK_DEV_INITRD 227 /* 228 * Relocate initrd if it is not completely within the linear mapping. 229 * This would be the case if mem= cuts out all or part of it. 230 */ 231 static void __init relocate_initrd(void) 232 { 233 phys_addr_t orig_start = __virt_to_phys(initrd_start); 234 phys_addr_t orig_end = __virt_to_phys(initrd_end); 235 phys_addr_t ram_end = memblock_end_of_DRAM(); 236 phys_addr_t new_start; 237 unsigned long size, to_free = 0; 238 void *dest; 239 240 if (orig_end <= ram_end) 241 return; 242 243 /* 244 * Any of the original initrd which overlaps the linear map should 245 * be freed after relocating. 246 */ 247 if (orig_start < ram_end) 248 to_free = ram_end - orig_start; 249 250 size = orig_end - orig_start; 251 if (!size) 252 return; 253 254 /* initrd needs to be relocated completely inside linear mapping */ 255 new_start = memblock_find_in_range(0, PFN_PHYS(max_pfn), 256 size, PAGE_SIZE); 257 if (!new_start) 258 panic("Cannot relocate initrd of size %ld\n", size); 259 memblock_reserve(new_start, size); 260 261 initrd_start = __phys_to_virt(new_start); 262 initrd_end = initrd_start + size; 263 264 pr_info("Moving initrd from [%llx-%llx] to [%llx-%llx]\n", 265 orig_start, orig_start + size - 1, 266 new_start, new_start + size - 1); 267 268 dest = (void *)initrd_start; 269 270 if (to_free) { 271 memcpy(dest, (void *)__phys_to_virt(orig_start), to_free); 272 dest += to_free; 273 } 274 275 copy_from_early_mem(dest, orig_start + to_free, size - to_free); 276 277 if (to_free) { 278 pr_info("Freeing original RAMDISK from [%llx-%llx]\n", 279 orig_start, orig_start + to_free - 1); 280 memblock_free(orig_start, to_free); 281 } 282 } 283 #else 284 static inline void __init relocate_initrd(void) 285 { 286 } 287 #endif 288 289 u64 __cpu_logical_map[NR_CPUS] = { [0 ... NR_CPUS-1] = INVALID_HWID }; 290 291 void __init setup_arch(char **cmdline_p) 292 { 293 pr_info("Boot CPU: AArch64 Processor [%08x]\n", read_cpuid_id()); 294 295 sprintf(init_utsname()->machine, ELF_PLATFORM); 296 init_mm.start_code = (unsigned long) _text; 297 init_mm.end_code = (unsigned long) _etext; 298 init_mm.end_data = (unsigned long) _edata; 299 init_mm.brk = (unsigned long) _end; 300 301 *cmdline_p = boot_command_line; 302 303 early_fixmap_init(); 304 early_ioremap_init(); 305 306 setup_machine_fdt(__fdt_pointer); 307 308 parse_early_param(); 309 310 /* 311 * Unmask asynchronous aborts after bringing up possible earlycon. 312 * (Report possible System Errors once we can report this occurred) 313 */ 314 local_async_enable(); 315 316 efi_init(); 317 arm64_memblock_init(); 318 319 /* Parse the ACPI tables for possible boot-time configuration */ 320 acpi_boot_table_init(); 321 322 paging_init(); 323 relocate_initrd(); 324 325 kasan_init(); 326 327 request_standard_resources(); 328 329 early_ioremap_reset(); 330 331 if (acpi_disabled) { 332 unflatten_device_tree(); 333 psci_dt_init(); 334 } else { 335 psci_acpi_init(); 336 } 337 xen_early_init(); 338 339 cpu_read_bootcpu_ops(); 340 smp_init_cpus(); 341 smp_build_mpidr_hash(); 342 343 #ifdef CONFIG_VT 344 #if defined(CONFIG_VGA_CONSOLE) 345 conswitchp = &vga_con; 346 #elif defined(CONFIG_DUMMY_CONSOLE) 347 conswitchp = &dummy_con; 348 #endif 349 #endif 350 if (boot_args[1] || boot_args[2] || boot_args[3]) { 351 pr_err("WARNING: x1-x3 nonzero in violation of boot protocol:\n" 352 "\tx1: %016llx\n\tx2: %016llx\n\tx3: %016llx\n" 353 "This indicates a broken bootloader or old kernel\n", 354 boot_args[1], boot_args[2], boot_args[3]); 355 } 356 } 357 358 static int __init arm64_device_init(void) 359 { 360 if (of_have_populated_dt()) { 361 of_iommu_init(); 362 of_platform_populate(NULL, of_default_bus_match_table, 363 NULL, NULL); 364 } else if (acpi_disabled) { 365 pr_crit("Device tree not populated\n"); 366 } 367 return 0; 368 } 369 arch_initcall_sync(arm64_device_init); 370 371 static int __init topology_init(void) 372 { 373 int i; 374 375 for_each_possible_cpu(i) { 376 struct cpu *cpu = &per_cpu(cpu_data.cpu, i); 377 cpu->hotpluggable = 1; 378 register_cpu(cpu, i); 379 } 380 381 return 0; 382 } 383 subsys_initcall(topology_init); 384