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         size &= PAGE_MASK;
 174         memblock_add(base, size);
 175 }
 176
 177 void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
 178 {
 179         return __va(memblock_alloc(size, align));
 180 }
 181
 182 /*
 183  * Limit the memory size that was specified via FDT.
 184  */
 185 static int __init early_mem(char *p)
 186 {
 187         phys_addr_t limit;
 188
 189         if (!p)
 190                 return 1;
 191
 192         limit = memparse(p, &p) & PAGE_MASK;
 193         pr_notice("Memory limited to %lldMB\n", limit >> 20);
 194
 195         memblock_enforce_memory_limit(limit);
 196
 197         return 0;
 198 }
 199 early_param("mem", early_mem);
 200
 201 static void __init request_standard_resources(void)
 202 {
 203         struct memblock_region *region;
 204         struct resource *res;
 205
 206         kernel_code.start   = virt_to_phys(_text);
 207         kernel_code.end     = virt_to_phys(_etext - 1);
 208         kernel_data.start   = virt_to_phys(_sdata);
 209         kernel_data.end     = virt_to_phys(_end - 1);
 210
 211         for_each_memblock(memory, region) {
 212                 res = alloc_bootmem_low(sizeof(*res));
 213                 res->name  = "System RAM";
 214                 res->start = __pfn_to_phys(memblock_region_memory_base_pfn(region));
 215                 res->end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1;
 216                 res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
 217
 218                 request_resource(&iomem_resource, res);
 219
 220                 if (kernel_code.start >= res->start &&
 221                     kernel_code.end <= res->end)
 222                         request_resource(res, &kernel_code);
 223                 if (kernel_data.start >= res->start &&
 224                     kernel_data.end <= res->end)
 225                         request_resource(res, &kernel_data);
 226         }
 227 }
 228
 229 void __init setup_arch(char **cmdline_p)
 230 {
 231         setup_processor();
 232
 233         setup_machine_fdt(__fdt_pointer);
 234
 235         init_mm.start_code = (unsigned long) _text;
 236         init_mm.end_code   = (unsigned long) _etext;
 237         init_mm.end_data   = (unsigned long) _edata;
 238         init_mm.brk        = (unsigned long) _end;
 239
 240         *cmdline_p = boot_command_line;
 241
 242         parse_early_param();
 243
 244         arm64_memblock_init();
 245
 246         paging_init();
 247         request_standard_resources();
 248
 249         unflatten_device_tree();
 250
 251 #ifdef CONFIG_SMP
 252         smp_init_cpus();
 253 #endif
 254
 255 #ifdef CONFIG_VT
 256 #if defined(CONFIG_VGA_CONSOLE)
 257         conswitchp = &vga_con;
 258 #elif defined(CONFIG_DUMMY_CONSOLE)
 259         conswitchp = &dummy_con;
 260 #endif
 261 #endif
 262 }
 263
 264 static DEFINE_PER_CPU(struct cpu, cpu_data);
 265
 266 static int __init topology_init(void)
 267 {
 268         int i;
 269
 270         for_each_possible_cpu(i) {
 271                 struct cpu *cpu = &per_cpu(cpu_data, i);
 272                 cpu->hotpluggable = 1;
 273                 register_cpu(cpu, i);
 274         }
 275
 276         return 0;
 277 }
 278 subsys_initcall(topology_init);
 279
 280 static const char *hwcap_str[] = {
 281         "fp",
 282         "asimd",
 283         NULL
 284 };
 285
 286 static int c_show(struct seq_file *m, void *v)
 287 {
 288         int i;
 289
 290         seq_printf(m, "Processor\t: %s rev %d (%s)\n",
 291                    cpu_name, read_cpuid_id() & 15, ELF_PLATFORM);
 292
 293         for_each_online_cpu(i) {
 294                 /*
 295                  * glibc reads /proc/cpuinfo to determine the number of
 296                  * online processors, looking for lines beginning with
 297                  * "processor".  Give glibc what it expects.
 298                  */
 299 #ifdef CONFIG_SMP
 300                 seq_printf(m, "processor\t: %d\n", i);
 301 #endif
 302                 seq_printf(m, "BogoMIPS\t: %lu.%02lu\n\n",
 303                            loops_per_jiffy / (500000UL/HZ),
 304                            loops_per_jiffy / (5000UL/HZ) % 100);
 305         }
 306
 307         /* dump out the processor features */
 308         seq_puts(m, "Features\t: ");
 309
 310         for (i = 0; hwcap_str[i]; i++)
 311                 if (elf_hwcap & (1 << i))
 312                         seq_printf(m, "%s ", hwcap_str[i]);
 313
 314         seq_printf(m, "\nCPU implementer\t: 0x%02x\n", read_cpuid_id() >> 24);
 315         seq_printf(m, "CPU architecture: AArch64\n");
 316         seq_printf(m, "CPU variant\t: 0x%x\n", (read_cpuid_id() >> 20) & 15);
 317         seq_printf(m, "CPU part\t: 0x%03x\n", (read_cpuid_id() >> 4) & 0xfff);
 318         seq_printf(m, "CPU revision\t: %d\n", read_cpuid_id() & 15);
 319
 320         seq_puts(m, "\n");
 321
 322         seq_printf(m, "Hardware\t: %s\n", machine_name);
 323
 324         return 0;
 325 }
 326
 327 static void *c_start(struct seq_file *m, loff_t *pos)
 328 {
 329         return *pos < 1 ? (void *)1 : NULL;
 330 }
 331
 332 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
 333 {
 334         ++*pos;
 335         return NULL;
 336 }
 337
 338 static void c_stop(struct seq_file *m, void *v)
 339 {
 340 }
 341
 342 const struct seq_operations cpuinfo_op = {
 343         .start  = c_start,
 344         .next   = c_next,
 345         .stop   = c_stop,
 346         .show   = c_show
 347 };