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