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
add_resource(struct resource * parent,struct resource * res)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
add_kernel_resources(void)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
init_resources(void)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_or_panic(mem_res_sz, SMP_CACHE_BYTES);
151
152 /*
153 * Start by adding the reserved regions, if they overlap
154 * with /memory regions, insert_resource later on will take
155 * care of it.
156 */
157 ret = add_kernel_resources();
158 if (ret < 0)
159 goto error;
160
161 #ifdef CONFIG_CRASH_DUMP
162 if (elfcorehdr_size > 0) {
163 elfcorehdr_res.start = elfcorehdr_addr;
164 elfcorehdr_res.end = elfcorehdr_addr + elfcorehdr_size - 1;
165 elfcorehdr_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
166 add_resource(&iomem_resource, &elfcorehdr_res);
167 }
168 #endif
169
170 for_each_reserved_mem_region(region) {
171 res = &mem_res[res_idx--];
172
173 res->name = "Reserved";
174 res->flags = IORESOURCE_MEM | IORESOURCE_EXCLUSIVE;
175 res->start = __pfn_to_phys(memblock_region_reserved_base_pfn(region));
176 res->end = __pfn_to_phys(memblock_region_reserved_end_pfn(region)) - 1;
177
178 /*
179 * Ignore any other reserved regions within
180 * system memory.
181 */
182 if (memblock_is_memory(res->start)) {
183 /* Re-use this pre-allocated resource */
184 res_idx++;
185 continue;
186 }
187
188 ret = add_resource(&iomem_resource, res);
189 if (ret < 0)
190 goto error;
191 }
192
193 /* Add /memory regions to the resource tree */
194 for_each_mem_region(region) {
195 res = &mem_res[res_idx--];
196
197 if (unlikely(memblock_is_nomap(region))) {
198 res->name = "Reserved";
199 res->flags = IORESOURCE_MEM | IORESOURCE_EXCLUSIVE;
200 } else {
201 res->name = "System RAM";
202 res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
203 }
204
205 res->start = __pfn_to_phys(memblock_region_memory_base_pfn(region));
206 res->end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1;
207
208 ret = add_resource(&iomem_resource, res);
209 if (ret < 0)
210 goto error;
211 }
212
213 /* Clean-up any unused pre-allocated resources */
214 if (res_idx >= 0)
215 memblock_free(mem_res, (res_idx + 1) * sizeof(*mem_res));
216 return;
217
218 error:
219 /* Better an empty resource tree than an inconsistent one */
220 release_child_resources(&iomem_resource);
221 memblock_free(mem_res, mem_res_sz);
222 }
223
224
parse_dtb(void)225 static void __init parse_dtb(void)
226 {
227 /* Early scan of device tree from init memory */
228 if (early_init_dt_scan(dtb_early_va, dtb_early_pa)) {
229 const char *name = of_flat_dt_get_machine_name();
230
231 if (name) {
232 pr_info("Machine model: %s\n", name);
233 dump_stack_set_arch_desc("%s (DT)", name);
234 }
235 } else {
236 pr_err("No DTB passed to the kernel\n");
237 }
238
239 #ifdef CONFIG_CMDLINE_FORCE
240 strscpy(boot_command_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
241 pr_info("Forcing kernel command line to: %s\n", boot_command_line);
242 #endif
243 }
244
245 #if defined(CONFIG_RISCV_COMBO_SPINLOCKS)
246 DEFINE_STATIC_KEY_TRUE(qspinlock_key);
247 EXPORT_SYMBOL(qspinlock_key);
248 #endif
249
riscv_spinlock_init(void)250 static void __init riscv_spinlock_init(void)
251 {
252 char *using_ext = NULL;
253
254 if (IS_ENABLED(CONFIG_RISCV_TICKET_SPINLOCKS)) {
255 pr_info("Ticket spinlock: enabled\n");
256 return;
257 }
258
259 if (IS_ENABLED(CONFIG_RISCV_ISA_ZABHA) &&
260 IS_ENABLED(CONFIG_RISCV_ISA_ZACAS) &&
261 riscv_isa_extension_available(NULL, ZABHA) &&
262 riscv_isa_extension_available(NULL, ZACAS)) {
263 using_ext = "using Zabha";
264 } else if (riscv_isa_extension_available(NULL, ZICCRSE)) {
265 using_ext = "using Ziccrse";
266 }
267 #if defined(CONFIG_RISCV_COMBO_SPINLOCKS)
268 else {
269 static_branch_disable(&qspinlock_key);
270 pr_info("Ticket spinlock: enabled\n");
271 return;
272 }
273 #endif
274
275 if (!using_ext)
276 pr_err("Queued spinlock without Zabha or Ziccrse");
277 else
278 pr_info("Queued spinlock %s: enabled\n", using_ext);
279 }
280
281 extern void __init init_rt_signal_env(void);
282
setup_arch(char ** cmdline_p)283 void __init setup_arch(char **cmdline_p)
284 {
285 parse_dtb();
286 setup_initial_init_mm(_stext, _etext, _edata, _end);
287
288 *cmdline_p = boot_command_line;
289
290 early_ioremap_setup();
291 sbi_init();
292 jump_label_init();
293 parse_early_param();
294
295 efi_init();
296 paging_init();
297
298 /* Parse the ACPI tables for possible boot-time configuration */
299 acpi_boot_table_init();
300
301 #if IS_ENABLED(CONFIG_BUILTIN_DTB)
302 unflatten_and_copy_device_tree();
303 #else
304 unflatten_device_tree();
305 #endif
306 misc_mem_init();
307
308 init_resources();
309
310 #ifdef CONFIG_KASAN
311 kasan_init();
312 #endif
313
314 #ifdef CONFIG_SMP
315 setup_smp();
316 #endif
317
318 if (!acpi_disabled) {
319 acpi_init_rintc_map();
320 acpi_map_cpus_to_nodes();
321 }
322
323 riscv_init_cbo_blocksizes();
324 riscv_fill_hwcap();
325 apply_boot_alternatives();
326 init_rt_signal_env();
327
328 if (IS_ENABLED(CONFIG_RISCV_ISA_ZICBOM) &&
329 riscv_isa_extension_available(NULL, ZICBOM))
330 riscv_noncoherent_supported();
331 riscv_set_dma_cache_alignment();
332
333 riscv_user_isa_enable();
334 riscv_spinlock_init();
335 }
336
arch_cpu_is_hotpluggable(int cpu)337 bool arch_cpu_is_hotpluggable(int cpu)
338 {
339 return cpu_has_hotplug(cpu);
340 }
341
free_initmem(void)342 void free_initmem(void)
343 {
344 if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)) {
345 set_kernel_memory(lm_alias(__init_begin), lm_alias(__init_end), set_memory_rw_nx);
346 if (IS_ENABLED(CONFIG_64BIT))
347 set_kernel_memory(__init_begin, __init_end, set_memory_nx);
348 }
349
350 free_initmem_default(POISON_FREE_INITMEM);
351 }
352
dump_kernel_offset(struct notifier_block * self,unsigned long v,void * p)353 static int dump_kernel_offset(struct notifier_block *self,
354 unsigned long v, void *p)
355 {
356 pr_emerg("Kernel Offset: 0x%lx from 0x%lx\n",
357 kernel_map.virt_offset,
358 KERNEL_LINK_ADDR);
359
360 return 0;
361 }
362
363 static struct notifier_block kernel_offset_notifier = {
364 .notifier_call = dump_kernel_offset
365 };
366
register_kernel_offset_dumper(void)367 static int __init register_kernel_offset_dumper(void)
368 {
369 if (IS_ENABLED(CONFIG_RANDOMIZE_BASE))
370 atomic_notifier_chain_register(&panic_notifier_list,
371 &kernel_offset_notifier);
372
373 return 0;
374 }
375 device_initcall(register_kernel_offset_dumper);
376