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/bootmem.h>
  29 #include <linux/seq_file.h>
  30 #include <linux/screen_info.h>
  31 #include <linux/init.h>
  32 #include <linux/kexec.h>
  33 #include <linux/crash_dump.h>
  34 #include <linux/root_dev.h>
  35 #include <linux/cpu.h>
  36 #include <linux/interrupt.h>
  37 #include <linux/smp.h>
  38 #include <linux/fs.h>
  39 #include <linux/proc_fs.h>
  40 #include <linux/memblock.h>
  41 #include <linux/of_fdt.h>
  42 #include <linux/of_platform.h>
  43
  44 #include <asm/cputype.h>
  45 #include <asm/elf.h>
  46 #include <asm/cputable.h>
  47 #include <asm/sections.h>
  48 #include <asm/setup.h>
  49 #include <asm/cacheflush.h>
  50 #include <asm/tlbflush.h>
  51 #include <asm/traps.h>
  52 #include <asm/memblock.h>
  53 #include <asm/psci.h>
  54
  55 unsigned int processor_id;
  56 EXPORT_SYMBOL(processor_id);
  57
  58 unsigned int elf_hwcap __read_mostly;
  59 EXPORT_SYMBOL_GPL(elf_hwcap);
  60
  61 static const char *cpu_name;
  62 static const char *machine_name;
  63 phys_addr_t __fdt_pointer __initdata;
  64
  65 /*
  66  * Standard memory resources
  67  */
  68 static struct resource mem_res[] = {
  69         {
  70                 .name = "Kernel code",
  71                 .start = 0,
  72                 .end = 0,
  73                 .flags = IORESOURCE_MEM
  74         },
  75         {
  76                 .name = "Kernel data",
  77                 .start = 0,
  78                 .end = 0,
  79                 .flags = IORESOURCE_MEM
  80         }
  81 };
  82
  83 #define kernel_code mem_res[0]
  84 #define kernel_data mem_res[1]
  85
  86 void __init early_print(const char *str, ...)
  87 {
  88         char buf[256];
  89         va_list ap;
  90
  91         va_start(ap, str);
  92         vsnprintf(buf, sizeof(buf), str, ap);
  93         va_end(ap);
  94
  95         printk("%s", buf);
  96 }
  97
  98 static void __init setup_processor(void)
  99 {
 100         struct cpu_info *cpu_info;
 101
 102         /*
 103          * locate processor in the list of supported processor
 104          * types.  The linker builds this table for us from the
 105          * entries in arch/arm/mm/proc.S
 106          */
 107         cpu_info = lookup_processor_type(read_cpuid_id());
 108         if (!cpu_info) {
 109                 printk("CPU configuration botched (ID %08x), unable to continue.\n",
 110                        read_cpuid_id());
 111                 while (1);
 112         }
 113
 114         cpu_name = cpu_info->cpu_name;
 115
 116         printk("CPU: %s [%08x] revision %d\n",
 117                cpu_name, read_cpuid_id(), read_cpuid_id() & 15);
 118
 119         sprintf(init_utsname()->machine, "aarch64");
 120         elf_hwcap = 0;
 121 }
 122
 123 static void __init setup_machine_fdt(phys_addr_t dt_phys)
 124 {
 125         struct boot_param_header *devtree;
 126         unsigned long dt_root;
 127
 128         /* Check we have a non-NULL DT pointer */
 129         if (!dt_phys) {
 130                 early_print("\n"
 131                         "Error: NULL or invalid device tree blob\n"
 132                         "The dtb must be 8-byte aligned and passed in the first 512MB of memory\n"
 133                         "\nPlease check your bootloader.\n");
 134
 135                 while (true)
 136                         cpu_relax();
 137
 138         }
 139
 140         devtree = phys_to_virt(dt_phys);
 141
 142         /* Check device tree validity */
 143         if (be32_to_cpu(devtree->magic) != OF_DT_HEADER) {
 144                 early_print("\n"
 145                         "Error: invalid device tree blob at physical address 0x%p (virtual address 0x%p)\n"
 146                         "Expected 0x%x, found 0x%x\n"
 147                         "\nPlease check your bootloader.\n",
 148                         dt_phys, devtree, OF_DT_HEADER,
 149                         be32_to_cpu(devtree->magic));
 150
 151                 while (true)
 152                         cpu_relax();
 153         }
 154
 155         initial_boot_params = devtree;
 156         dt_root = of_get_flat_dt_root();
 157
 158         machine_name = of_get_flat_dt_prop(dt_root, "model", NULL);
 159         if (!machine_name)
 160                 machine_name = of_get_flat_dt_prop(dt_root, "compatible", NULL);
 161         if (!machine_name)
 162                 machine_name = "<unknown>";
 163         pr_info("Machine: %s\n", machine_name);
 164
 165         /* Retrieve various information from the /chosen node */
 166         of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line);
 167         /* Initialize {size,address}-cells info */
 168         of_scan_flat_dt(early_init_dt_scan_root, NULL);
 169         /* Setup memory, calling early_init_dt_add_memory_arch */
 170         of_scan_flat_dt(early_init_dt_scan_memory, NULL);
 171 }
 172
 173 void __init early_init_dt_add_memory_arch(u64 base, u64 size)
 174 {
 175         base &= PAGE_MASK;
 176         size &= PAGE_MASK;
 177         if (base + size < PHYS_OFFSET) {
 178                 pr_warning("Ignoring memory block 0x%llx - 0x%llx\n",
 179                            base, base + size);
 180                 return;
 181         }
 182         if (base < PHYS_OFFSET) {
 183                 pr_warning("Ignoring memory range 0x%llx - 0x%llx\n",
 184                            base, PHYS_OFFSET);
 185                 size -= PHYS_OFFSET - base;
 186                 base = PHYS_OFFSET;
 187         }
 188         memblock_add(base, size);
 189 }
 190
 191 void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
 192 {
 193         return __va(memblock_alloc(size, align));
 194 }
 195
 196 /*
 197  * Limit the memory size that was specified via FDT.
 198  */
 199 static int __init early_mem(char *p)
 200 {
 201         phys_addr_t limit;
 202
 203         if (!p)
 204                 return 1;
 205
 206         limit = memparse(p, &p) & PAGE_MASK;
 207         pr_notice("Memory limited to %lldMB\n", limit >> 20);
 208
 209         memblock_enforce_memory_limit(limit);
 210
 211         return 0;
 212 }
 213 early_param("mem", early_mem);
 214
 215 static void __init request_standard_resources(void)
 216 {
 217         struct memblock_region *region;
 218         struct resource *res;
 219
 220         kernel_code.start   = virt_to_phys(_text);
 221         kernel_code.end     = virt_to_phys(_etext - 1);
 222         kernel_data.start   = virt_to_phys(_sdata);
 223         kernel_data.end     = virt_to_phys(_end - 1);
 224
 225         for_each_memblock(memory, region) {
 226                 res = alloc_bootmem_low(sizeof(*res));
 227                 res->name  = "System RAM";
 228                 res->start = __pfn_to_phys(memblock_region_memory_base_pfn(region));
 229                 res->end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1;
 230                 res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
 231
 232                 request_resource(&iomem_resource, res);
 233
 234                 if (kernel_code.start >= res->start &&
 235                     kernel_code.end <= res->end)
 236                         request_resource(res, &kernel_code);
 237                 if (kernel_data.start >= res->start &&
 238                     kernel_data.end <= res->end)
 239                         request_resource(res, &kernel_data);
 240         }
 241 }
 242
 243 void __init setup_arch(char **cmdline_p)
 244 {
 245         setup_processor();
 246
 247         setup_machine_fdt(__fdt_pointer);
 248
 249         init_mm.start_code = (unsigned long) _text;
 250         init_mm.end_code   = (unsigned long) _etext;
 251         init_mm.end_data   = (unsigned long) _edata;
 252         init_mm.brk        = (unsigned long) _end;
 253
 254         *cmdline_p = boot_command_line;
 255
 256         parse_early_param();
 257
 258         arm64_memblock_init();
 259
 260         paging_init();
 261         request_standard_resources();
 262
 263         unflatten_device_tree();
 264
 265         psci_init();
 266
 267 #ifdef CONFIG_SMP
 268         smp_init_cpus();
 269 #endif
 270
 271 #ifdef CONFIG_VT
 272 #if defined(CONFIG_VGA_CONSOLE)
 273         conswitchp = &vga_con;
 274 #elif defined(CONFIG_DUMMY_CONSOLE)
 275         conswitchp = &dummy_con;
 276 #endif
 277 #endif
 278 }
 279
 280 static DEFINE_PER_CPU(struct cpu, cpu_data);
 281
 282 static int __init topology_init(void)
 283 {
 284         int i;
 285
 286         for_each_possible_cpu(i) {
 287                 struct cpu *cpu = &per_cpu(cpu_data, i);
 288                 cpu->hotpluggable = 1;
 289                 register_cpu(cpu, i);
 290         }
 291
 292         return 0;
 293 }
 294 subsys_initcall(topology_init);
 295
 296 static int __init arm64_device_probe(void)
 297 {
 298         of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
 299         return 0;
 300 }
 301 device_initcall(arm64_device_probe);
 302
 303 static const char *hwcap_str[] = {
 304         "fp",
 305         "asimd",
 306         NULL
 307 };
 308
 309 static int c_show(struct seq_file *m, void *v)
 310 {
 311         int i;
 312
 313         seq_printf(m, "Processor\t: %s rev %d (%s)\n",
 314                    cpu_name, read_cpuid_id() & 15, ELF_PLATFORM);
 315
 316         for_each_online_cpu(i) {
 317                 /*
 318                  * glibc reads /proc/cpuinfo to determine the number of
 319                  * online processors, looking for lines beginning with
 320                  * "processor".  Give glibc what it expects.
 321                  */
 322 #ifdef CONFIG_SMP
 323                 seq_printf(m, "processor\t: %d\n", i);
 324 #endif
 325                 seq_printf(m, "BogoMIPS\t: %lu.%02lu\n\n",
 326                            loops_per_jiffy / (500000UL/HZ),
 327                            loops_per_jiffy / (5000UL/HZ) % 100);
 328         }
 329
 330         /* dump out the processor features */
 331         seq_puts(m, "Features\t: ");
 332
 333         for (i = 0; hwcap_str[i]; i++)
 334                 if (elf_hwcap & (1 << i))
 335                         seq_printf(m, "%s ", hwcap_str[i]);
 336
 337         seq_printf(m, "\nCPU implementer\t: 0x%02x\n", read_cpuid_id() >> 24);
 338         seq_printf(m, "CPU architecture: AArch64\n");
 339         seq_printf(m, "CPU variant\t: 0x%x\n", (read_cpuid_id() >> 20) & 15);
 340         seq_printf(m, "CPU part\t: 0x%03x\n", (read_cpuid_id() >> 4) & 0xfff);
 341         seq_printf(m, "CPU revision\t: %d\n", read_cpuid_id() & 15);
 342
 343         seq_puts(m, "\n");
 344
 345         seq_printf(m, "Hardware\t: %s\n", machine_name);
 346
 347         return 0;
 348 }
 349
 350 static void *c_start(struct seq_file *m, loff_t *pos)
 351 {
 352         return *pos < 1 ? (void *)1 : NULL;
 353 }
 354
 355 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
 356 {
 357         ++*pos;
 358         return NULL;
 359 }
 360
 361 static void c_stop(struct seq_file *m, void *v)
 362 {
 363 }
 364
 365 const struct seq_operations cpuinfo_op = {
 366         .start  = c_start,
 367         .next   = c_next,
 368         .stop   = c_stop,
 369         .show   = c_show
 370 };