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/init.h>
  12 #include <linux/mm.h>
  13 #include <linux/memblock.h>
  14 #include <linux/sched.h>
  15 #include <linux/console.h>
  16 #include <linux/screen_info.h>
  17 #include <linux/of_fdt.h>
  18 #include <linux/of_platform.h>
  19 #include <linux/sched/task.h>
  20 #include <linux/smp.h>
  21 #include <linux/efi.h>
  22 #include <linux/crash_dump.h>
  23
  24 #include <asm/cpu_ops.h>
  25 #include <asm/early_ioremap.h>
  26 #include <asm/pgtable.h>
  27 #include <asm/setup.h>
  28 #include <asm/set_memory.h>
  29 #include <asm/sections.h>
  30 #include <asm/sbi.h>
  31 #include <asm/tlbflush.h>
  32 #include <asm/thread_info.h>
  33 #include <asm/kasan.h>
  34 #include <asm/efi.h>
  35
  36 #include "head.h"
  37
  38 #if defined(CONFIG_DUMMY_CONSOLE) || defined(CONFIG_EFI)
  39 struct screen_info screen_info __section(".data") = {
  40         .orig_video_lines       = 30,
  41         .orig_video_cols        = 80,
  42         .orig_video_mode        = 0,
  43         .orig_video_ega_bx      = 0,
  44         .orig_video_isVGA       = 1,
  45         .orig_video_points      = 8
  46 };
  47 #endif
  48
  49 /*
  50  * The lucky hart to first increment this variable will boot the other cores.
  51  * This is used before the kernel initializes the BSS so it can't be in the
  52  * BSS.
  53  */
  54 atomic_t hart_lottery __section(".sdata")
  55 #ifdef CONFIG_XIP_KERNEL
  56 = ATOMIC_INIT(0xC001BEEF)
  57 #endif
  58 ;
  59 unsigned long boot_cpu_hartid;
  60 static DEFINE_PER_CPU(struct cpu, cpu_devices);
  61
  62 /*
  63  * Place kernel memory regions on the resource tree so that
  64  * kexec-tools can retrieve them from /proc/iomem. While there
  65  * also add "System RAM" regions for compatibility with other
  66  * archs, and the rest of the known regions for completeness.
  67  */
  68 static struct resource kimage_res = { .name = "Kernel image", };
  69 static struct resource code_res = { .name = "Kernel code", };
  70 static struct resource data_res = { .name = "Kernel data", };
  71 static struct resource rodata_res = { .name = "Kernel rodata", };
  72 static struct resource bss_res = { .name = "Kernel bss", };
  73 #ifdef CONFIG_CRASH_DUMP
  74 static struct resource elfcorehdr_res = { .name = "ELF Core hdr", };
  75 #endif
  76
  77 static int __init add_resource(struct resource *parent,
  78                                 struct resource *res)
  79 {
  80         int ret = 0;
  81
  82         ret = insert_resource(parent, res);
  83         if (ret < 0) {
  84                 pr_err("Failed to add a %s resource at %llx\n",
  85                         res->name, (unsigned long long) res->start);
  86                 return ret;
  87         }
  88
  89         return 1;
  90 }
  91
  92 static int __init add_kernel_resources(void)
  93 {
  94         int ret = 0;
  95
  96         /*
  97          * The memory region of the kernel image is continuous and
  98          * was reserved on setup_bootmem, register it here as a
  99          * resource, with the various segments of the image as
 100          * child nodes.
 101          */
 102
 103         code_res.start = __pa_symbol(_text);
 104         code_res.end = __pa_symbol(_etext) - 1;
 105         code_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 106
 107         rodata_res.start = __pa_symbol(__start_rodata);
 108         rodata_res.end = __pa_symbol(__end_rodata) - 1;
 109         rodata_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 110
 111         data_res.start = __pa_symbol(_data);
 112         data_res.end = __pa_symbol(_edata) - 1;
 113         data_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 114
 115         bss_res.start = __pa_symbol(__bss_start);
 116         bss_res.end = __pa_symbol(__bss_stop) - 1;
 117         bss_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 118
 119         kimage_res.start = code_res.start;
 120         kimage_res.end = bss_res.end;
 121         kimage_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 122
 123         ret = add_resource(&iomem_resource, &kimage_res);
 124         if (ret < 0)
 125                 return ret;
 126
 127         ret = add_resource(&kimage_res, &code_res);
 128         if (ret < 0)
 129                 return ret;
 130
 131         ret = add_resource(&kimage_res, &rodata_res);
 132         if (ret < 0)
 133                 return ret;
 134
 135         ret = add_resource(&kimage_res, &data_res);
 136         if (ret < 0)
 137                 return ret;
 138
 139         ret = add_resource(&kimage_res, &bss_res);
 140
 141         return ret;
 142 }
 143
 144 static void __init init_resources(void)
 145 {
 146         struct memblock_region *region = NULL;
 147         struct resource *res = NULL;
 148         struct resource *mem_res = NULL;
 149         size_t mem_res_sz = 0;
 150         int num_resources = 0, res_idx = 0;
 151         int ret = 0;
 152
 153         /* + 1 as memblock_alloc() might increase memblock.reserved.cnt */
 154         num_resources = memblock.memory.cnt + memblock.reserved.cnt + 1;
 155         res_idx = num_resources - 1;
 156
 157         mem_res_sz = num_resources * sizeof(*mem_res);
 158         mem_res = memblock_alloc(mem_res_sz, SMP_CACHE_BYTES);
 159         if (!mem_res)
 160                 panic("%s: Failed to allocate %zu bytes\n", __func__, mem_res_sz);
 161
 162         /*
 163          * Start by adding the reserved regions, if they overlap
 164          * with /memory regions, insert_resource later on will take
 165          * care of it.
 166          */
 167         ret = add_kernel_resources();
 168         if (ret < 0)
 169                 goto error;
 170
 171 #ifdef CONFIG_KEXEC_CORE
 172         if (crashk_res.start != crashk_res.end) {
 173                 ret = add_resource(&iomem_resource, &crashk_res);
 174                 if (ret < 0)
 175                         goto error;
 176         }
 177 #endif
 178
 179 #ifdef CONFIG_CRASH_DUMP
 180         if (elfcorehdr_size > 0) {
 181                 elfcorehdr_res.start = elfcorehdr_addr;
 182                 elfcorehdr_res.end = elfcorehdr_addr + elfcorehdr_size - 1;
 183                 elfcorehdr_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 184                 add_resource(&iomem_resource, &elfcorehdr_res);
 185         }
 186 #endif
 187
 188         for_each_reserved_mem_region(region) {
 189                 res = &mem_res[res_idx--];
 190
 191                 res->name = "Reserved";
 192                 res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
 193                 res->start = __pfn_to_phys(memblock_region_reserved_base_pfn(region));
 194                 res->end = __pfn_to_phys(memblock_region_reserved_end_pfn(region)) - 1;
 195
 196                 /*
 197                  * Ignore any other reserved regions within
 198                  * system memory.
 199                  */
 200                 if (memblock_is_memory(res->start)) {
 201                         /* Re-use this pre-allocated resource */
 202                         res_idx++;
 203                         continue;
 204                 }
 205
 206                 ret = add_resource(&iomem_resource, res);
 207                 if (ret < 0)
 208                         goto error;
 209         }
 210
 211         /* Add /memory regions to the resource tree */
 212         for_each_mem_region(region) {
 213                 res = &mem_res[res_idx--];
 214
 215                 if (unlikely(memblock_is_nomap(region))) {
 216                         res->name = "Reserved";
 217                         res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
 218                 } else {
 219                         res->name = "System RAM";
 220                         res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 221                 }
 222
 223                 res->start = __pfn_to_phys(memblock_region_memory_base_pfn(region));
 224                 res->end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1;
 225
 226                 ret = add_resource(&iomem_resource, res);
 227                 if (ret < 0)
 228                         goto error;
 229         }
 230
 231         /* Clean-up any unused pre-allocated resources */
 232         if (res_idx >= 0)
 233                 memblock_free(__pa(mem_res), (res_idx + 1) * sizeof(*mem_res));
 234         return;
 235
 236  error:
 237         /* Better an empty resource tree than an inconsistent one */
 238         release_child_resources(&iomem_resource);
 239         memblock_free(__pa(mem_res), mem_res_sz);
 240 }
 241
 242
 243 static void __init parse_dtb(void)
 244 {
 245         /* Early scan of device tree from init memory */
 246         if (early_init_dt_scan(dtb_early_va)) {
 247                 const char *name = of_flat_dt_get_machine_name();
 248
 249                 if (name) {
 250                         pr_info("Machine model: %s\n", name);
 251                         dump_stack_set_arch_desc("%s (DT)", name);
 252                 }
 253                 return;
 254         }
 255
 256         pr_err("No DTB passed to the kernel\n");
 257 #ifdef CONFIG_CMDLINE_FORCE
 258         strscpy(boot_command_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
 259         pr_info("Forcing kernel command line to: %s\n", boot_command_line);
 260 #endif
 261 }
 262
 263 void __init setup_arch(char **cmdline_p)
 264 {
 265         parse_dtb();
 266         setup_initial_init_mm(_stext, _etext, _edata, _end);
 267
 268         *cmdline_p = boot_command_line;
 269
 270         early_ioremap_setup();
 271         jump_label_init();
 272         parse_early_param();
 273
 274         efi_init();
 275         paging_init();
 276 #if IS_ENABLED(CONFIG_BUILTIN_DTB)
 277         unflatten_and_copy_device_tree();
 278 #else
 279         if (early_init_dt_verify(__va(XIP_FIXUP(dtb_early_pa))))
 280                 unflatten_device_tree();
 281         else
 282                 pr_err("No DTB found in kernel mappings\n");
 283 #endif
 284         misc_mem_init();
 285
 286         init_resources();
 287         sbi_init();
 288
 289 #ifdef CONFIG_KASAN
 290         kasan_init();
 291 #endif
 292
 293 #ifdef CONFIG_SMP
 294         setup_smp();
 295 #endif
 296
 297         riscv_fill_hwcap();
 298 }
 299
 300 static int __init topology_init(void)
 301 {
 302         int i, ret;
 303
 304         for_each_online_node(i)
 305                 register_one_node(i);
 306
 307         for_each_possible_cpu(i) {
 308                 struct cpu *cpu = &per_cpu(cpu_devices, i);
 309
 310                 cpu->hotpluggable = cpu_has_hotplug(i);
 311                 ret = register_cpu(cpu, i);
 312                 if (unlikely(ret))
 313                         pr_warn("Warning: %s: register_cpu %d failed (%d)\n",
 314                                __func__, i, ret);
 315         }
 316
 317         return 0;
 318 }
 319 subsys_initcall(topology_init);
 320
 321 void free_initmem(void)
 322 {
 323         if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX))
 324                 set_kernel_memory(lm_alias(__init_begin), lm_alias(__init_end),
 325                                   IS_ENABLED(CONFIG_64BIT) ?
 326                                         set_memory_rw : set_memory_rw_nx);
 327
 328         free_initmem_default(POISON_FREE_INITMEM);
 329 }