arch/riscv/kernel/setup.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Copyright (C) 2009 Sunplus Core Technology Co., Ltd.
   4  *  Chen Liqin <liqin.chen@sunplusct.com>
   5  *  Lennox Wu <lennox.wu@sunplusct.com>
   6  * Copyright (C) 2012 Regents of the University of California
   7  * Copyright (C) 2020 FORTH-ICS/CARV
   8  *  Nick Kossifidis <mick@ics.forth.gr>
   9  */
  10
  11 #include <linux/acpi.h>
  12 #include <linux/cpu.h>
  13 #include <linux/init.h>
  14 #include <linux/mm.h>
  15 #include <linux/memblock.h>
  16 #include <linux/sched.h>
  17 #include <linux/console.h>
  18 #include <linux/screen_info.h>
  19 #include <linux/of_fdt.h>
  20 #include <linux/sched/task.h>
  21 #include <linux/smp.h>
  22 #include <linux/efi.h>
  23 #include <linux/crash_dump.h>
  24 #include <linux/panic_notifier.h>
  25
  26 #include <asm/acpi.h>
  27 #include <asm/alternative.h>
  28 #include <asm/cacheflush.h>
  29 #include <asm/cpu_ops.h>
  30 #include <asm/early_ioremap.h>
  31 #include <asm/pgtable.h>
  32 #include <asm/setup.h>
  33 #include <asm/set_memory.h>
  34 #include <asm/sections.h>
  35 #include <asm/sbi.h>
  36 #include <asm/tlbflush.h>
  37 #include <asm/thread_info.h>
  38 #include <asm/kasan.h>
  39 #include <asm/efi.h>
  40
  41 #include "head.h"
  42
  43 #if defined(CONFIG_DUMMY_CONSOLE) || defined(CONFIG_EFI)
  44 struct screen_info screen_info __section(".data") = {
  45         .orig_video_lines       = 30,
  46         .orig_video_cols        = 80,
  47         .orig_video_mode        = 0,
  48         .orig_video_ega_bx      = 0,
  49         .orig_video_isVGA       = 1,
  50         .orig_video_points      = 8
  51 };
  52 #endif
  53
  54 /*
  55  * The lucky hart to first increment this variable will boot the other cores.
  56  * This is used before the kernel initializes the BSS so it can't be in the
  57  * BSS.
  58  */
  59 atomic_t hart_lottery __section(".sdata")
  60 #ifdef CONFIG_XIP_KERNEL
  61 = ATOMIC_INIT(0xC001BEEF)
  62 #endif
  63 ;
  64 unsigned long boot_cpu_hartid;
  65 static DEFINE_PER_CPU(struct cpu, cpu_devices);
  66
  67 /*
  68  * Place kernel memory regions on the resource tree so that
  69  * kexec-tools can retrieve them from /proc/iomem. While there
  70  * also add "System RAM" regions for compatibility with other
  71  * archs, and the rest of the known regions for completeness.
  72  */
  73 static struct resource kimage_res = { .name = "Kernel image", };
  74 static struct resource code_res = { .name = "Kernel code", };
  75 static struct resource data_res = { .name = "Kernel data", };
  76 static struct resource rodata_res = { .name = "Kernel rodata", };
  77 static struct resource bss_res = { .name = "Kernel bss", };
  78 #ifdef CONFIG_CRASH_DUMP
  79 static struct resource elfcorehdr_res = { .name = "ELF Core hdr", };
  80 #endif
  81
  82 static int __init add_resource(struct resource *parent,
  83                                 struct resource *res)
  84 {
  85         int ret = 0;
  86
  87         ret = insert_resource(parent, res);
  88         if (ret < 0) {
  89                 pr_err("Failed to add a %s resource at %llx\n",
  90                         res->name, (unsigned long long) res->start);
  91                 return ret;
  92         }
  93
  94         return 1;
  95 }
  96
  97 static int __init add_kernel_resources(void)
  98 {
  99         int ret = 0;
 100
 101         /*
 102          * The memory region of the kernel image is continuous and
 103          * was reserved on setup_bootmem, register it here as a
 104          * resource, with the various segments of the image as
 105          * child nodes.
 106          */
 107
 108         code_res.start = __pa_symbol(_text);
 109         code_res.end = __pa_symbol(_etext) - 1;
 110         code_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 111
 112         rodata_res.start = __pa_symbol(__start_rodata);
 113         rodata_res.end = __pa_symbol(__end_rodata) - 1;
 114         rodata_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 115
 116         data_res.start = __pa_symbol(_data);
 117         data_res.end = __pa_symbol(_edata) - 1;
 118         data_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 119
 120         bss_res.start = __pa_symbol(__bss_start);
 121         bss_res.end = __pa_symbol(__bss_stop) - 1;
 122         bss_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 123
 124         kimage_res.start = code_res.start;
 125         kimage_res.end = bss_res.end;
 126         kimage_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 127
 128         ret = add_resource(&iomem_resource, &kimage_res);
 129         if (ret < 0)
 130                 return ret;
 131
 132         ret = add_resource(&kimage_res, &code_res);
 133         if (ret < 0)
 134                 return ret;
 135
 136         ret = add_resource(&kimage_res, &rodata_res);
 137         if (ret < 0)
 138                 return ret;
 139
 140         ret = add_resource(&kimage_res, &data_res);
 141         if (ret < 0)
 142                 return ret;
 143
 144         ret = add_resource(&kimage_res, &bss_res);
 145
 146         return ret;
 147 }
 148
 149 static void __init init_resources(void)
 150 {
 151         struct memblock_region *region = NULL;
 152         struct resource *res = NULL;
 153         struct resource *mem_res = NULL;
 154         size_t mem_res_sz = 0;
 155         int num_resources = 0, res_idx = 0;
 156         int ret = 0;
 157
 158         /* + 1 as memblock_alloc() might increase memblock.reserved.cnt */
 159         num_resources = memblock.memory.cnt + memblock.reserved.cnt + 1;
 160         res_idx = num_resources - 1;
 161
 162         mem_res_sz = num_resources * sizeof(*mem_res);
 163         mem_res = memblock_alloc(mem_res_sz, SMP_CACHE_BYTES);
 164         if (!mem_res)
 165                 panic("%s: Failed to allocate %zu bytes\n", __func__, mem_res_sz);
 166
 167         /*
 168          * Start by adding the reserved regions, if they overlap
 169          * with /memory regions, insert_resource later on will take
 170          * care of it.
 171          */
 172         ret = add_kernel_resources();
 173         if (ret < 0)
 174                 goto error;
 175
 176 #ifdef CONFIG_KEXEC_CORE
 177         if (crashk_res.start != crashk_res.end) {
 178                 ret = add_resource(&iomem_resource, &crashk_res);
 179                 if (ret < 0)
 180                         goto error;
 181         }
 182 #endif
 183
 184 #ifdef CONFIG_CRASH_DUMP
 185         if (elfcorehdr_size > 0) {
 186                 elfcorehdr_res.start = elfcorehdr_addr;
 187                 elfcorehdr_res.end = elfcorehdr_addr + elfcorehdr_size - 1;
 188                 elfcorehdr_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 189                 add_resource(&iomem_resource, &elfcorehdr_res);
 190         }
 191 #endif
 192
 193         for_each_reserved_mem_region(region) {
 194                 res = &mem_res[res_idx--];
 195
 196                 res->name = "Reserved";
 197                 res->flags = IORESOURCE_MEM | IORESOURCE_EXCLUSIVE;
 198                 res->start = __pfn_to_phys(memblock_region_reserved_base_pfn(region));
 199                 res->end = __pfn_to_phys(memblock_region_reserved_end_pfn(region)) - 1;
 200
 201                 /*
 202                  * Ignore any other reserved regions within
 203                  * system memory.
 204                  */
 205                 if (memblock_is_memory(res->start)) {
 206                         /* Re-use this pre-allocated resource */
 207                         res_idx++;
 208                         continue;
 209                 }
 210
 211                 ret = add_resource(&iomem_resource, res);
 212                 if (ret < 0)
 213                         goto error;
 214         }
 215
 216         /* Add /memory regions to the resource tree */
 217         for_each_mem_region(region) {
 218                 res = &mem_res[res_idx--];
 219
 220                 if (unlikely(memblock_is_nomap(region))) {
 221                         res->name = "Reserved";
 222                         res->flags = IORESOURCE_MEM | IORESOURCE_EXCLUSIVE;
 223                 } else {
 224                         res->name = "System RAM";
 225                         res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 226                 }
 227
 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
 231                 ret = add_resource(&iomem_resource, res);
 232                 if (ret < 0)
 233                         goto error;
 234         }
 235
 236         /* Clean-up any unused pre-allocated resources */
 237         if (res_idx >= 0)
 238                 memblock_free(mem_res, (res_idx + 1) * sizeof(*mem_res));
 239         return;
 240
 241  error:
 242         /* Better an empty resource tree than an inconsistent one */
 243         release_child_resources(&iomem_resource);
 244         memblock_free(mem_res, mem_res_sz);
 245 }
 246
 247
 248 static void __init parse_dtb(void)
 249 {
 250         /* Early scan of device tree from init memory */
 251         if (early_init_dt_scan(dtb_early_va)) {
 252                 const char *name = of_flat_dt_get_machine_name();
 253
 254                 if (name) {
 255                         pr_info("Machine model: %s\n", name);
 256                         dump_stack_set_arch_desc("%s (DT)", name);
 257                 }
 258         } else {
 259                 pr_err("No DTB passed to the kernel\n");
 260         }
 261
 262 #ifdef CONFIG_CMDLINE_FORCE
 263         strscpy(boot_command_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
 264         pr_info("Forcing kernel command line to: %s\n", boot_command_line);
 265 #endif
 266 }
 267
 268 extern void __init init_rt_signal_env(void);
 269
 270 void __init setup_arch(char **cmdline_p)
 271 {
 272         parse_dtb();
 273         setup_initial_init_mm(_stext, _etext, _edata, _end);
 274
 275         *cmdline_p = boot_command_line;
 276
 277         early_ioremap_setup();
 278         sbi_init();
 279         jump_label_init();
 280         parse_early_param();
 281
 282         efi_init();
 283         paging_init();
 284
 285         /* Parse the ACPI tables for possible boot-time configuration */
 286         acpi_boot_table_init();
 287
 288 #if IS_ENABLED(CONFIG_BUILTIN_DTB)
 289         unflatten_and_copy_device_tree();
 290 #else
 291         unflatten_device_tree();
 292 #endif
 293         misc_mem_init();
 294
 295         init_resources();
 296
 297 #ifdef CONFIG_KASAN
 298         kasan_init();
 299 #endif
 300
 301 #ifdef CONFIG_SMP
 302         setup_smp();
 303 #endif
 304
 305         if (!acpi_disabled)
 306                 acpi_init_rintc_map();
 307
 308         riscv_init_cbo_blocksizes();
 309         riscv_fill_hwcap();
 310         init_rt_signal_env();
 311         apply_boot_alternatives();
 312         if (IS_ENABLED(CONFIG_RISCV_ISA_ZICBOM) &&
 313             riscv_isa_extension_available(NULL, ZICBOM))
 314                 riscv_noncoherent_supported();
 315 }
 316
 317 static int __init topology_init(void)
 318 {
 319         int i, ret;
 320
 321         for_each_possible_cpu(i) {
 322                 struct cpu *cpu = &per_cpu(cpu_devices, i);
 323
 324                 cpu->hotpluggable = cpu_has_hotplug(i);
 325                 ret = register_cpu(cpu, i);
 326                 if (unlikely(ret))
 327                         pr_warn("Warning: %s: register_cpu %d failed (%d)\n",
 328                                __func__, i, ret);
 329         }
 330
 331         return 0;
 332 }
 333 subsys_initcall(topology_init);
 334
 335 void free_initmem(void)
 336 {
 337         if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)) {
 338                 set_kernel_memory(lm_alias(__init_begin), lm_alias(__init_end), set_memory_rw_nx);
 339                 if (IS_ENABLED(CONFIG_64BIT))
 340                         set_kernel_memory(__init_begin, __init_end, set_memory_nx);
 341         }
 342
 343         free_initmem_default(POISON_FREE_INITMEM);
 344 }
 345
 346 static int dump_kernel_offset(struct notifier_block *self,
 347                               unsigned long v, void *p)
 348 {
 349         pr_emerg("Kernel Offset: 0x%lx from 0x%lx\n",
 350                  kernel_map.virt_offset,
 351                  KERNEL_LINK_ADDR);
 352
 353         return 0;
 354 }
 355
 356 static struct notifier_block kernel_offset_notifier = {
 357         .notifier_call = dump_kernel_offset
 358 };
 359
 360 static int __init register_kernel_offset_dumper(void)
 361 {
 362         if (IS_ENABLED(CONFIG_RANDOMIZE_BASE))
 363                 atomic_notifier_chain_register(&panic_notifier_list,
 364                                                &kernel_offset_notifier);
 365
 366         return 0;
 367 }
 368 device_initcall(register_kernel_offset_dumper);