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/swiotlb.h>
  21 #include <linux/smp.h>
  22 #include <linux/efi.h>
  23 #include <linux/crash_dump.h>
  24
  25 #include <asm/cpu_ops.h>
  26 #include <asm/early_ioremap.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 unsigned long boot_cpu_hartid;
  56 static DEFINE_PER_CPU(struct cpu, cpu_devices);
  57
  58 /*
  59  * Place kernel memory regions on the resource tree so that
  60  * kexec-tools can retrieve them from /proc/iomem. While there
  61  * also add "System RAM" regions for compatibility with other
  62  * archs, and the rest of the known regions for completeness.
  63  */
  64 static struct resource kimage_res = { .name = "Kernel image", };
  65 static struct resource code_res = { .name = "Kernel code", };
  66 static struct resource data_res = { .name = "Kernel data", };
  67 static struct resource rodata_res = { .name = "Kernel rodata", };
  68 static struct resource bss_res = { .name = "Kernel bss", };
  69
  70 static int __init add_resource(struct resource *parent,
  71                                 struct resource *res)
  72 {
  73         int ret = 0;
  74
  75         ret = insert_resource(parent, res);
  76         if (ret < 0) {
  77                 pr_err("Failed to add a %s resource at %llx\n",
  78                         res->name, (unsigned long long) res->start);
  79                 return ret;
  80         }
  81
  82         return 1;
  83 }
  84
  85 static int __init add_kernel_resources(void)
  86 {
  87         int ret = 0;
  88
  89         /*
  90          * The memory region of the kernel image is continuous and
  91          * was reserved on setup_bootmem, register it here as a
  92          * resource, with the various segments of the image as
  93          * child nodes.
  94          */
  95
  96         code_res.start = __pa_symbol(_text);
  97         code_res.end = __pa_symbol(_etext) - 1;
  98         code_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
  99
 100         rodata_res.start = __pa_symbol(__start_rodata);
 101         rodata_res.end = __pa_symbol(__end_rodata) - 1;
 102         rodata_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 103
 104         data_res.start = __pa_symbol(_data);
 105         data_res.end = __pa_symbol(_edata) - 1;
 106         data_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 107
 108         bss_res.start = __pa_symbol(__bss_start);
 109         bss_res.end = __pa_symbol(__bss_stop) - 1;
 110         bss_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 111
 112         kimage_res.start = code_res.start;
 113         kimage_res.end = bss_res.end;
 114         kimage_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 115
 116         ret = add_resource(&iomem_resource, &kimage_res);
 117         if (ret < 0)
 118                 return ret;
 119
 120         ret = add_resource(&kimage_res, &code_res);
 121         if (ret < 0)
 122                 return ret;
 123
 124         ret = add_resource(&kimage_res, &rodata_res);
 125         if (ret < 0)
 126                 return ret;
 127
 128         ret = add_resource(&kimage_res, &data_res);
 129         if (ret < 0)
 130                 return ret;
 131
 132         ret = add_resource(&kimage_res, &bss_res);
 133
 134         return ret;
 135 }
 136
 137 static void __init init_resources(void)
 138 {
 139         struct memblock_region *region = NULL;
 140         struct resource *res = NULL;
 141         struct resource *mem_res = NULL;
 142         size_t mem_res_sz = 0;
 143         int num_resources = 0, res_idx = 0;
 144         int ret = 0;
 145
 146         /* + 1 as memblock_alloc() might increase memblock.reserved.cnt */
 147         num_resources = memblock.memory.cnt + memblock.reserved.cnt + 1;
 148         res_idx = num_resources - 1;
 149
 150         mem_res_sz = num_resources * sizeof(*mem_res);
 151         mem_res = memblock_alloc(mem_res_sz, SMP_CACHE_BYTES);
 152         if (!mem_res)
 153                 panic("%s: Failed to allocate %zu bytes\n", __func__, mem_res_sz);
 154
 155         /*
 156          * Start by adding the reserved regions, if they overlap
 157          * with /memory regions, insert_resource later on will take
 158          * care of it.
 159          */
 160         ret = add_kernel_resources();
 161         if (ret < 0)
 162                 goto error;
 163
 164 #ifdef CONFIG_KEXEC_CORE
 165         if (crashk_res.start != crashk_res.end) {
 166                 ret = add_resource(&iomem_resource, &crashk_res);
 167                 if (ret < 0)
 168                         goto error;
 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_BUSY;
 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_BUSY;
 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         mem_res_sz = (num_resources - res_idx + 1) * sizeof(*mem_res);
 217         memblock_free((phys_addr_t) mem_res, mem_res_sz);
 218         return;
 219
 220  error:
 221         /* Better an empty resource tree than an inconsistent one */
 222         release_child_resources(&iomem_resource);
 223         memblock_free((phys_addr_t) 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                 return;
 238         }
 239
 240         pr_err("No DTB passed to the kernel\n");
 241 #ifdef CONFIG_CMDLINE_FORCE
 242         strlcpy(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 void __init setup_arch(char **cmdline_p)
 248 {
 249         parse_dtb();
 250         init_mm.start_code = (unsigned long) _stext;
 251         init_mm.end_code   = (unsigned long) _etext;
 252         init_mm.end_data   = (unsigned long) _edata;
 253         init_mm.brk        = (unsigned long) _end;
 254
 255         *cmdline_p = boot_command_line;
 256
 257         early_ioremap_setup();
 258         jump_label_init();
 259         parse_early_param();
 260
 261         efi_init();
 262         setup_bootmem();
 263         paging_init();
 264 #if IS_ENABLED(CONFIG_BUILTIN_DTB)
 265         unflatten_and_copy_device_tree();
 266 #else
 267         if (early_init_dt_verify(__va(dtb_early_pa)))
 268                 unflatten_device_tree();
 269         else
 270                 pr_err("No DTB found in kernel mappings\n");
 271 #endif
 272         misc_mem_init();
 273
 274         init_resources();
 275         sbi_init();
 276
 277         if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)) {
 278                 protect_kernel_text_data();
 279 #if defined(CONFIG_64BIT) && defined(CONFIG_MMU)
 280                 protect_kernel_linear_mapping_text_rodata();
 281 #endif
 282         }
 283
 284 #ifdef CONFIG_SWIOTLB
 285         swiotlb_init(1);
 286 #endif
 287
 288 #ifdef CONFIG_KASAN
 289         kasan_init();
 290 #endif
 291
 292 #ifdef CONFIG_SMP
 293         setup_smp();
 294 #endif
 295
 296         riscv_fill_hwcap();
 297 }
 298
 299 static int __init topology_init(void)
 300 {
 301         int i, ret;
 302
 303         for_each_online_node(i)
 304                 register_one_node(i);
 305
 306         for_each_possible_cpu(i) {
 307                 struct cpu *cpu = &per_cpu(cpu_devices, i);
 308
 309                 cpu->hotpluggable = cpu_has_hotplug(i);
 310                 ret = register_cpu(cpu, i);
 311                 if (unlikely(ret))
 312                         pr_warn("Warning: %s: register_cpu %d failed (%d)\n",
 313                                __func__, i, ret);
 314         }
 315
 316         return 0;
 317 }
 318 subsys_initcall(topology_init);
 319
 320 void free_initmem(void)
 321 {
 322         unsigned long init_begin = (unsigned long)__init_begin;
 323         unsigned long init_end = (unsigned long)__init_end;
 324
 325         if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX))
 326                 set_memory_rw_nx(init_begin, (init_end - init_begin) >> PAGE_SHIFT);
 327
 328         free_initmem_default(POISON_FREE_INITMEM);
 329 }