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/of_fdt.h>
  19 #include <linux/sched/task.h>
  20 #include <linux/smp.h>
  21 #include <linux/efi.h>
  22 #include <linux/crash_dump.h>
  23 #include <linux/panic_notifier.h>
  24
  25 #include <asm/acpi.h>
  26 #include <asm/alternative.h>
  27 #include <asm/cacheflush.h>
  28 #include <asm/cpufeature.h>
  29 #include <asm/early_ioremap.h>
  30 #include <asm/pgtable.h>
  31 #include <asm/setup.h>
  32 #include <asm/set_memory.h>
  33 #include <asm/sections.h>
  34 #include <asm/sbi.h>
  35 #include <asm/tlbflush.h>
  36 #include <asm/thread_info.h>
  37 #include <asm/kasan.h>
  38 #include <asm/efi.h>
  39
  40 #include "head.h"
  41
  42 /*
  43  * The lucky hart to first increment this variable will boot the other cores.
  44  * This is used before the kernel initializes the BSS so it can't be in the
  45  * BSS.
  46  */
  47 atomic_t hart_lottery __section(".sdata")
  48 #ifdef CONFIG_XIP_KERNEL
  49 = ATOMIC_INIT(0xC001BEEF)
  50 #endif
  51 ;
  52 unsigned long boot_cpu_hartid;
  53
  54 /*
  55  * Place kernel memory regions on the resource tree so that
  56  * kexec-tools can retrieve them from /proc/iomem. While there
  57  * also add "System RAM" regions for compatibility with other
  58  * archs, and the rest of the known regions for completeness.
  59  */
  60 static struct resource kimage_res = { .name = "Kernel image", };
  61 static struct resource code_res = { .name = "Kernel code", };
  62 static struct resource data_res = { .name = "Kernel data", };
  63 static struct resource rodata_res = { .name = "Kernel rodata", };
  64 static struct resource bss_res = { .name = "Kernel bss", };
  65 #ifdef CONFIG_CRASH_DUMP
  66 static struct resource elfcorehdr_res = { .name = "ELF Core hdr", };
  67 #endif
  68
  69 static int __init add_resource(struct resource *parent,
  70                                 struct resource *res)
  71 {
  72         int ret = 0;
  73
  74         ret = insert_resource(parent, res);
  75         if (ret < 0) {
  76                 pr_err("Failed to add a %s resource at %llx\n",
  77                         res->name, (unsigned long long) res->start);
  78                 return ret;
  79         }
  80
  81         return 1;
  82 }
  83
  84 static int __init add_kernel_resources(void)
  85 {
  86         int ret = 0;
  87
  88         /*
  89          * The memory region of the kernel image is continuous and
  90          * was reserved on setup_bootmem, register it here as a
  91          * resource, with the various segments of the image as
  92          * child nodes.
  93          */
  94
  95         code_res.start = __pa_symbol(_text);
  96         code_res.end = __pa_symbol(_etext) - 1;
  97         code_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
  98
  99         rodata_res.start = __pa_symbol(__start_rodata);
 100         rodata_res.end = __pa_symbol(__end_rodata) - 1;
 101         rodata_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 102
 103         data_res.start = __pa_symbol(_data);
 104         data_res.end = __pa_symbol(_edata) - 1;
 105         data_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 106
 107         bss_res.start = __pa_symbol(__bss_start);
 108         bss_res.end = __pa_symbol(__bss_stop) - 1;
 109         bss_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 110
 111         kimage_res.start = code_res.start;
 112         kimage_res.end = bss_res.end;
 113         kimage_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 114
 115         ret = add_resource(&iomem_resource, &kimage_res);
 116         if (ret < 0)
 117                 return ret;
 118
 119         ret = add_resource(&kimage_res, &code_res);
 120         if (ret < 0)
 121                 return ret;
 122
 123         ret = add_resource(&kimage_res, &rodata_res);
 124         if (ret < 0)
 125                 return ret;
 126
 127         ret = add_resource(&kimage_res, &data_res);
 128         if (ret < 0)
 129                 return ret;
 130
 131         ret = add_resource(&kimage_res, &bss_res);
 132
 133         return ret;
 134 }
 135
 136 static void __init init_resources(void)
 137 {
 138         struct memblock_region *region = NULL;
 139         struct resource *res = NULL;
 140         struct resource *mem_res = NULL;
 141         size_t mem_res_sz = 0;
 142         int num_resources = 0, res_idx = 0;
 143         int ret = 0;
 144
 145         /* + 1 as memblock_alloc() might increase memblock.reserved.cnt */
 146         num_resources = memblock.memory.cnt + memblock.reserved.cnt + 1;
 147         res_idx = num_resources - 1;
 148
 149         mem_res_sz = num_resources * sizeof(*mem_res);
 150         mem_res = memblock_alloc(mem_res_sz, SMP_CACHE_BYTES);
 151         if (!mem_res)
 152                 panic("%s: Failed to allocate %zu bytes\n", __func__, mem_res_sz);
 153
 154         /*
 155          * Start by adding the reserved regions, if they overlap
 156          * with /memory regions, insert_resource later on will take
 157          * care of it.
 158          */
 159         ret = add_kernel_resources();
 160         if (ret < 0)
 161                 goto error;
 162
 163 #ifdef CONFIG_CRASH_DUMP
 164         if (elfcorehdr_size > 0) {
 165                 elfcorehdr_res.start = elfcorehdr_addr;
 166                 elfcorehdr_res.end = elfcorehdr_addr + elfcorehdr_size - 1;
 167                 elfcorehdr_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 168                 add_resource(&iomem_resource, &elfcorehdr_res);
 169         }
 170 #endif
 171
 172         for_each_reserved_mem_region(region) {
 173                 res = &mem_res[res_idx--];
 174
 175                 res->name = "Reserved";
 176                 res->flags = IORESOURCE_MEM | IORESOURCE_EXCLUSIVE;
 177                 res->start = __pfn_to_phys(memblock_region_reserved_base_pfn(region));
 178                 res->end = __pfn_to_phys(memblock_region_reserved_end_pfn(region)) - 1;
 179
 180                 /*
 181                  * Ignore any other reserved regions within
 182                  * system memory.
 183                  */
 184                 if (memblock_is_memory(res->start)) {
 185                         /* Re-use this pre-allocated resource */
 186                         res_idx++;
 187                         continue;
 188                 }
 189
 190                 ret = add_resource(&iomem_resource, res);
 191                 if (ret < 0)
 192                         goto error;
 193         }
 194
 195         /* Add /memory regions to the resource tree */
 196         for_each_mem_region(region) {
 197                 res = &mem_res[res_idx--];
 198
 199                 if (unlikely(memblock_is_nomap(region))) {
 200                         res->name = "Reserved";
 201                         res->flags = IORESOURCE_MEM | IORESOURCE_EXCLUSIVE;
 202                 } else {
 203                         res->name = "System RAM";
 204                         res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 205                 }
 206
 207                 res->start = __pfn_to_phys(memblock_region_memory_base_pfn(region));
 208                 res->end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1;
 209
 210                 ret = add_resource(&iomem_resource, res);
 211                 if (ret < 0)
 212                         goto error;
 213         }
 214
 215         /* Clean-up any unused pre-allocated resources */
 216         if (res_idx >= 0)
 217                 memblock_free(mem_res, (res_idx + 1) * sizeof(*mem_res));
 218         return;
 219
 220  error:
 221         /* Better an empty resource tree than an inconsistent one */
 222         release_child_resources(&iomem_resource);
 223         memblock_free(mem_res, mem_res_sz);
 224 }
 225
 226
 227 static void __init parse_dtb(void)
 228 {
 229         /* Early scan of device tree from init memory */
 230         if (early_init_dt_scan(dtb_early_va)) {
 231                 const char *name = of_flat_dt_get_machine_name();
 232
 233                 if (name) {
 234                         pr_info("Machine model: %s\n", name);
 235                         dump_stack_set_arch_desc("%s (DT)", name);
 236                 }
 237         } else {
 238                 pr_err("No DTB passed to the kernel\n");
 239         }
 240
 241 #ifdef CONFIG_CMDLINE_FORCE
 242         strscpy(boot_command_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
 243         pr_info("Forcing kernel command line to: %s\n", boot_command_line);
 244 #endif
 245 }
 246
 247 extern void __init init_rt_signal_env(void);
 248
 249 void __init setup_arch(char **cmdline_p)
 250 {
 251         parse_dtb();
 252         setup_initial_init_mm(_stext, _etext, _edata, _end);
 253
 254         *cmdline_p = boot_command_line;
 255
 256         early_ioremap_setup();
 257         sbi_init();
 258         jump_label_init();
 259         parse_early_param();
 260
 261         efi_init();
 262         paging_init();
 263
 264         /* Parse the ACPI tables for possible boot-time configuration */
 265         acpi_boot_table_init();
 266
 267 #if IS_ENABLED(CONFIG_BUILTIN_DTB)
 268         unflatten_and_copy_device_tree();
 269 #else
 270         unflatten_device_tree();
 271 #endif
 272         misc_mem_init();
 273
 274         init_resources();
 275
 276 #ifdef CONFIG_KASAN
 277         kasan_init();
 278 #endif
 279
 280 #ifdef CONFIG_SMP
 281         setup_smp();
 282 #endif
 283
 284         if (!acpi_disabled)
 285                 acpi_init_rintc_map();
 286
 287         riscv_init_cbo_blocksizes();
 288         riscv_fill_hwcap();
 289         init_rt_signal_env();
 290         apply_boot_alternatives();
 291
 292         if (IS_ENABLED(CONFIG_RISCV_ISA_ZICBOM) &&
 293             riscv_isa_extension_available(NULL, ZICBOM))
 294                 riscv_noncoherent_supported();
 295         riscv_set_dma_cache_alignment();
 296
 297         riscv_user_isa_enable();
 298 }
 299
 300 bool arch_cpu_is_hotpluggable(int cpu)
 301 {
 302         return cpu_has_hotplug(cpu);
 303 }
 304
 305 void free_initmem(void)
 306 {
 307         if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)) {
 308                 set_kernel_memory(lm_alias(__init_begin), lm_alias(__init_end), set_memory_rw_nx);
 309                 if (IS_ENABLED(CONFIG_64BIT))
 310                         set_kernel_memory(__init_begin, __init_end, set_memory_nx);
 311         }
 312
 313         free_initmem_default(POISON_FREE_INITMEM);
 314 }
 315
 316 static int dump_kernel_offset(struct notifier_block *self,
 317                               unsigned long v, void *p)
 318 {
 319         pr_emerg("Kernel Offset: 0x%lx from 0x%lx\n",
 320                  kernel_map.virt_offset,
 321                  KERNEL_LINK_ADDR);
 322
 323         return 0;
 324 }
 325
 326 static struct notifier_block kernel_offset_notifier = {
 327         .notifier_call = dump_kernel_offset
 328 };
 329
 330 static int __init register_kernel_offset_dumper(void)
 331 {
 332         if (IS_ENABLED(CONFIG_RANDOMIZE_BASE))
 333                 atomic_notifier_chain_register(&panic_notifier_list,
 334                                                &kernel_offset_notifier);
 335
 336         return 0;
 337 }
 338 device_initcall(register_kernel_offset_dumper);