arch/arm64/kernel/setup.c

   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/export.h>
  21 #include <linux/kernel.h>
  22 #include <linux/stddef.h>
  23 #include <linux/ioport.h>
  24 #include <linux/delay.h>
  25 #include <linux/utsname.h>
  26 #include <linux/initrd.h>
  27 #include <linux/console.h>
  28 #include <linux/cache.h>
  29 #include <linux/bootmem.h>
  30 #include <linux/seq_file.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/clk-provider.h>
  37 #include <linux/cpu.h>
  38 #include <linux/interrupt.h>
  39 #include <linux/smp.h>
  40 #include <linux/fs.h>
  41 #include <linux/proc_fs.h>
  42 #include <linux/memblock.h>
  43 #include <linux/of_fdt.h>
  44 #include <linux/of_platform.h>
  45 #include <linux/efi.h>
  46
  47 #include <asm/fixmap.h>
  48 #include <asm/cpu.h>
  49 #include <asm/cputype.h>
  50 #include <asm/elf.h>
  51 #include <asm/cputable.h>
  52 #include <asm/cpu_ops.h>
  53 #include <asm/sections.h>
  54 #include <asm/setup.h>
  55 #include <asm/smp_plat.h>
  56 #include <asm/cacheflush.h>
  57 #include <asm/tlbflush.h>
  58 #include <asm/traps.h>
  59 #include <asm/memblock.h>
  60 #include <asm/psci.h>
  61 #include <asm/efi.h>
  62
  63 unsigned int processor_id;
  64 EXPORT_SYMBOL(processor_id);
  65
  66 unsigned long elf_hwcap __read_mostly;
  67 EXPORT_SYMBOL_GPL(elf_hwcap);
  68
  69 #ifdef CONFIG_COMPAT
  70 #define COMPAT_ELF_HWCAP_DEFAULT        \
  71                                 (COMPAT_HWCAP_HALF|COMPAT_HWCAP_THUMB|\
  72                                  COMPAT_HWCAP_FAST_MULT|COMPAT_HWCAP_EDSP|\
  73                                  COMPAT_HWCAP_TLS|COMPAT_HWCAP_VFP|\
  74                                  COMPAT_HWCAP_VFPv3|COMPAT_HWCAP_VFPv4|\
  75                                  COMPAT_HWCAP_NEON|COMPAT_HWCAP_IDIV)
  76 unsigned int compat_elf_hwcap __read_mostly = COMPAT_ELF_HWCAP_DEFAULT;
  77 unsigned int compat_elf_hwcap2 __read_mostly;
  78 #endif
  79
  80 static const char *cpu_name;
  81 phys_addr_t __fdt_pointer __initdata;
  82
  83 /*
  84  * Standard memory resources
  85  */
  86 static struct resource mem_res[] = {
  87         {
  88                 .name = "Kernel code",
  89                 .start = 0,
  90                 .end = 0,
  91                 .flags = IORESOURCE_MEM
  92         },
  93         {
  94                 .name = "Kernel data",
  95                 .start = 0,
  96                 .end = 0,
  97                 .flags = IORESOURCE_MEM
  98         }
  99 };
 100
 101 #define kernel_code mem_res[0]
 102 #define kernel_data mem_res[1]
 103
 104 void __init early_print(const char *str, ...)
 105 {
 106         char buf[256];
 107         va_list ap;
 108
 109         va_start(ap, str);
 110         vsnprintf(buf, sizeof(buf), str, ap);
 111         va_end(ap);
 112
 113         printk("%s", buf);
 114 }
 115
 116 void __init smp_setup_processor_id(void)
 117 {
 118         /*
 119          * clear __my_cpu_offset on boot CPU to avoid hang caused by
 120          * using percpu variable early, for example, lockdep will
 121          * access percpu variable inside lock_release
 122          */
 123         set_my_cpu_offset(0);
 124 }
 125
 126 bool arch_match_cpu_phys_id(int cpu, u64 phys_id)
 127 {
 128         return phys_id == cpu_logical_map(cpu);
 129 }
 130
 131 struct mpidr_hash mpidr_hash;
 132 #ifdef CONFIG_SMP
 133 /**
 134  * smp_build_mpidr_hash - Pre-compute shifts required at each affinity
 135  *                        level in order to build a linear index from an
 136  *                        MPIDR value. Resulting algorithm is a collision
 137  *                        free hash carried out through shifting and ORing
 138  */
 139 static void __init smp_build_mpidr_hash(void)
 140 {
 141         u32 i, affinity, fs[4], bits[4], ls;
 142         u64 mask = 0;
 143         /*
 144          * Pre-scan the list of MPIDRS and filter out bits that do
 145          * not contribute to affinity levels, ie they never toggle.
 146          */
 147         for_each_possible_cpu(i)
 148                 mask |= (cpu_logical_map(i) ^ cpu_logical_map(0));
 149         pr_debug("mask of set bits %#llx\n", mask);
 150         /*
 151          * Find and stash the last and first bit set at all affinity levels to
 152          * check how many bits are required to represent them.
 153          */
 154         for (i = 0; i < 4; i++) {
 155                 affinity = MPIDR_AFFINITY_LEVEL(mask, i);
 156                 /*
 157                  * Find the MSB bit and LSB bits position
 158                  * to determine how many bits are required
 159                  * to express the affinity level.
 160                  */
 161                 ls = fls(affinity);
 162                 fs[i] = affinity ? ffs(affinity) - 1 : 0;
 163                 bits[i] = ls - fs[i];
 164         }
 165         /*
 166          * An index can be created from the MPIDR_EL1 by isolating the
 167          * significant bits at each affinity level and by shifting
 168          * them in order to compress the 32 bits values space to a
 169          * compressed set of values. This is equivalent to hashing
 170          * the MPIDR_EL1 through shifting and ORing. It is a collision free
 171          * hash though not minimal since some levels might contain a number
 172          * of CPUs that is not an exact power of 2 and their bit
 173          * representation might contain holes, eg MPIDR_EL1[7:0] = {0x2, 0x80}.
 174          */
 175         mpidr_hash.shift_aff[0] = MPIDR_LEVEL_SHIFT(0) + fs[0];
 176         mpidr_hash.shift_aff[1] = MPIDR_LEVEL_SHIFT(1) + fs[1] - bits[0];
 177         mpidr_hash.shift_aff[2] = MPIDR_LEVEL_SHIFT(2) + fs[2] -
 178                                                 (bits[1] + bits[0]);
 179         mpidr_hash.shift_aff[3] = MPIDR_LEVEL_SHIFT(3) +
 180                                   fs[3] - (bits[2] + bits[1] + bits[0]);
 181         mpidr_hash.mask = mask;
 182         mpidr_hash.bits = bits[3] + bits[2] + bits[1] + bits[0];
 183         pr_debug("MPIDR hash: aff0[%u] aff1[%u] aff2[%u] aff3[%u] mask[%#llx] bits[%u]\n",
 184                 mpidr_hash.shift_aff[0],
 185                 mpidr_hash.shift_aff[1],
 186                 mpidr_hash.shift_aff[2],
 187                 mpidr_hash.shift_aff[3],
 188                 mpidr_hash.mask,
 189                 mpidr_hash.bits);
 190         /*
 191          * 4x is an arbitrary value used to warn on a hash table much bigger
 192          * than expected on most systems.
 193          */
 194         if (mpidr_hash_size() > 4 * num_possible_cpus())
 195                 pr_warn("Large number of MPIDR hash buckets detected\n");
 196         __flush_dcache_area(&mpidr_hash, sizeof(struct mpidr_hash));
 197 }
 198 #endif
 199
 200 static void __init setup_processor(void)
 201 {
 202         struct cpu_info *cpu_info;
 203         u64 features, block;
 204         u32 cwg;
 205         int cls;
 206
 207         cpu_info = lookup_processor_type(read_cpuid_id());
 208         if (!cpu_info) {
 209                 printk("CPU configuration botched (ID %08x), unable to continue.\n",
 210                        read_cpuid_id());
 211                 while (1);
 212         }
 213
 214         cpu_name = cpu_info->cpu_name;
 215
 216         printk("CPU: %s [%08x] revision %d\n",
 217                cpu_name, read_cpuid_id(), read_cpuid_id() & 15);
 218
 219         sprintf(init_utsname()->machine, ELF_PLATFORM);
 220         elf_hwcap = 0;
 221
 222         cpuinfo_store_boot_cpu();
 223
 224         /*
 225          * Check for sane CTR_EL0.CWG value.
 226          */
 227         cwg = cache_type_cwg();
 228         cls = cache_line_size();
 229         if (!cwg)
 230                 pr_warn("No Cache Writeback Granule information, assuming cache line size %d\n",
 231                         cls);
 232         if (L1_CACHE_BYTES < cls)
 233                 pr_warn("L1_CACHE_BYTES smaller than the Cache Writeback Granule (%d < %d)\n",
 234                         L1_CACHE_BYTES, cls);
 235
 236         /*
 237          * ID_AA64ISAR0_EL1 contains 4-bit wide signed feature blocks.
 238          * The blocks we test below represent incremental functionality
 239          * for non-negative values. Negative values are reserved.
 240          */
 241         features = read_cpuid(ID_AA64ISAR0_EL1);
 242         block = (features >> 4) & 0xf;
 243         if (!(block & 0x8)) {
 244                 switch (block) {
 245                 default:
 246                 case 2:
 247                         elf_hwcap |= HWCAP_PMULL;
 248                 case 1:
 249                         elf_hwcap |= HWCAP_AES;
 250                 case 0:
 251                         break;
 252                 }
 253         }
 254
 255         block = (features >> 8) & 0xf;
 256         if (block && !(block & 0x8))
 257                 elf_hwcap |= HWCAP_SHA1;
 258
 259         block = (features >> 12) & 0xf;
 260         if (block && !(block & 0x8))
 261                 elf_hwcap |= HWCAP_SHA2;
 262
 263         block = (features >> 16) & 0xf;
 264         if (block && !(block & 0x8))
 265                 elf_hwcap |= HWCAP_CRC32;
 266
 267 #ifdef CONFIG_COMPAT
 268         /*
 269          * ID_ISAR5_EL1 carries similar information as above, but pertaining to
 270          * the Aarch32 32-bit execution state.
 271          */
 272         features = read_cpuid(ID_ISAR5_EL1);
 273         block = (features >> 4) & 0xf;
 274         if (!(block & 0x8)) {
 275                 switch (block) {
 276                 default:
 277                 case 2:
 278                         compat_elf_hwcap2 |= COMPAT_HWCAP2_PMULL;
 279                 case 1:
 280                         compat_elf_hwcap2 |= COMPAT_HWCAP2_AES;
 281                 case 0:
 282                         break;
 283                 }
 284         }
 285
 286         block = (features >> 8) & 0xf;
 287         if (block && !(block & 0x8))
 288                 compat_elf_hwcap2 |= COMPAT_HWCAP2_SHA1;
 289
 290         block = (features >> 12) & 0xf;
 291         if (block && !(block & 0x8))
 292                 compat_elf_hwcap2 |= COMPAT_HWCAP2_SHA2;
 293
 294         block = (features >> 16) & 0xf;
 295         if (block && !(block & 0x8))
 296                 compat_elf_hwcap2 |= COMPAT_HWCAP2_CRC32;
 297 #endif
 298 }
 299
 300 static void __init setup_machine_fdt(phys_addr_t dt_phys)
 301 {
 302         if (!dt_phys || !early_init_dt_scan(phys_to_virt(dt_phys))) {
 303                 early_print("\n"
 304                         "Error: invalid device tree blob at physical address 0x%p (virtual address 0x%p)\n"
 305                         "The dtb must be 8-byte aligned and passed in the first 512MB of memory\n"
 306                         "\nPlease check your bootloader.\n",
 307                         dt_phys, phys_to_virt(dt_phys));
 308
 309                 while (true)
 310                         cpu_relax();
 311         }
 312 }
 313
 314 /*
 315  * Limit the memory size that was specified via FDT.
 316  */
 317 static int __init early_mem(char *p)
 318 {
 319         phys_addr_t limit;
 320
 321         if (!p)
 322                 return 1;
 323
 324         limit = memparse(p, &p) & PAGE_MASK;
 325         pr_notice("Memory limited to %lldMB\n", limit >> 20);
 326
 327         memblock_enforce_memory_limit(limit);
 328
 329         return 0;
 330 }
 331 early_param("mem", early_mem);
 332
 333 static void __init request_standard_resources(void)
 334 {
 335         struct memblock_region *region;
 336         struct resource *res;
 337
 338         kernel_code.start   = virt_to_phys(_text);
 339         kernel_code.end     = virt_to_phys(_etext - 1);
 340         kernel_data.start   = virt_to_phys(_sdata);
 341         kernel_data.end     = virt_to_phys(_end - 1);
 342
 343         for_each_memblock(memory, region) {
 344                 res = alloc_bootmem_low(sizeof(*res));
 345                 res->name  = "System RAM";
 346                 res->start = __pfn_to_phys(memblock_region_memory_base_pfn(region));
 347                 res->end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1;
 348                 res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
 349
 350                 request_resource(&iomem_resource, res);
 351
 352                 if (kernel_code.start >= res->start &&
 353                     kernel_code.end <= res->end)
 354                         request_resource(res, &kernel_code);
 355                 if (kernel_data.start >= res->start &&
 356                     kernel_data.end <= res->end)
 357                         request_resource(res, &kernel_data);
 358         }
 359 }
 360
 361 u64 __cpu_logical_map[NR_CPUS] = { [0 ... NR_CPUS-1] = INVALID_HWID };
 362
 363 void __init setup_arch(char **cmdline_p)
 364 {
 365         /*
 366          * Unmask asynchronous aborts early to catch possible system errors.
 367          */
 368         local_async_enable();
 369
 370         setup_processor();
 371
 372         setup_machine_fdt(__fdt_pointer);
 373
 374         init_mm.start_code = (unsigned long) _text;
 375         init_mm.end_code   = (unsigned long) _etext;
 376         init_mm.end_data   = (unsigned long) _edata;
 377         init_mm.brk        = (unsigned long) _end;
 378
 379         *cmdline_p = boot_command_line;
 380
 381         early_ioremap_init();
 382
 383         parse_early_param();
 384
 385         efi_init();
 386         arm64_memblock_init();
 387
 388         paging_init();
 389         request_standard_resources();
 390
 391         efi_idmap_init();
 392
 393         unflatten_device_tree();
 394
 395         psci_init();
 396
 397         cpu_logical_map(0) = read_cpuid_mpidr() & MPIDR_HWID_BITMASK;
 398         cpu_read_bootcpu_ops();
 399 #ifdef CONFIG_SMP
 400         smp_init_cpus();
 401         smp_build_mpidr_hash();
 402 #endif
 403
 404 #ifdef CONFIG_VT
 405 #if defined(CONFIG_VGA_CONSOLE)
 406         conswitchp = &vga_con;
 407 #elif defined(CONFIG_DUMMY_CONSOLE)
 408         conswitchp = &dummy_con;
 409 #endif
 410 #endif
 411 }
 412
 413 static int __init arm64_device_init(void)
 414 {
 415         of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
 416         return 0;
 417 }
 418 arch_initcall_sync(arm64_device_init);
 419
 420 static int __init topology_init(void)
 421 {
 422         int i;
 423
 424         for_each_possible_cpu(i) {
 425                 struct cpu *cpu = &per_cpu(cpu_data.cpu, i);
 426                 cpu->hotpluggable = 1;
 427                 register_cpu(cpu, i);
 428         }
 429
 430         return 0;
 431 }
 432 subsys_initcall(topology_init);
 433
 434 static const char *hwcap_str[] = {
 435         "fp",
 436         "asimd",
 437         "evtstrm",
 438         "aes",
 439         "pmull",
 440         "sha1",
 441         "sha2",
 442         "crc32",
 443         NULL
 444 };
 445
 446 static int c_show(struct seq_file *m, void *v)
 447 {
 448         int i;
 449
 450         /*
 451          * Dump out the common processor features in a single line. Userspace
 452          * should read the hwcaps with getauxval(AT_HWCAP) rather than
 453          * attempting to parse this.
 454          */
 455         seq_puts(m, "features\t:");
 456         for (i = 0; hwcap_str[i]; i++)
 457                 if (elf_hwcap & (1 << i))
 458                         seq_printf(m, " %s", hwcap_str[i]);
 459         seq_puts(m, "\n\n");
 460
 461         for_each_online_cpu(i) {
 462                 struct cpuinfo_arm64 *cpuinfo = &per_cpu(cpu_data, i);
 463                 u32 midr = cpuinfo->reg_midr;
 464
 465                 /*
 466                  * glibc reads /proc/cpuinfo to determine the number of
 467                  * online processors, looking for lines beginning with
 468                  * "processor".  Give glibc what it expects.
 469                  */
 470 #ifdef CONFIG_SMP
 471                 seq_printf(m, "processor\t: %d\n", i);
 472 #endif
 473                 seq_printf(m, "implementer\t: 0x%02x\n",
 474                            MIDR_IMPLEMENTOR(midr));
 475                 seq_printf(m, "variant\t\t: 0x%x\n", MIDR_VARIANT(midr));
 476                 seq_printf(m, "partnum\t\t: 0x%03x\n", MIDR_PARTNUM(midr));
 477                 seq_printf(m, "revision\t: 0x%x\n\n", MIDR_REVISION(midr));
 478         }
 479
 480         return 0;
 481 }
 482
 483 static void *c_start(struct seq_file *m, loff_t *pos)
 484 {
 485         return *pos < 1 ? (void *)1 : NULL;
 486 }
 487
 488 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
 489 {
 490         ++*pos;
 491         return NULL;
 492 }
 493
 494 static void c_stop(struct seq_file *m, void *v)
 495 {
 496 }
 497
 498 const struct seq_operations cpuinfo_op = {
 499         .start  = c_start,
 500         .next   = c_next,
 501         .stop   = c_stop,
 502         .show   = c_show
 503 };