1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Copyright (C) 2009 Sunplus Core Technology Co., Ltd.
4 * Chen Liqin <[email protected]>
5 * Lennox Wu <[email protected]>
6 * Copyright (C) 2012 Regents of the University of California
7 * Copyright (C) 2020 FORTH-ICS/CARV
8 * Nick Kossifidis <[email protected]>
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 num_standard_resources;
70 static struct resource *standard_resources;
71
add_resource(struct resource * parent,struct resource * res)72 static int __init add_resource(struct resource *parent,
73 struct resource *res)
74 {
75 int ret = 0;
76
77 ret = insert_resource(parent, res);
78 if (ret < 0) {
79 pr_err("Failed to add a %s resource at %llx\n",
80 res->name, (unsigned long long) res->start);
81 return ret;
82 }
83
84 return 1;
85 }
86
add_kernel_resources(void)87 static int __init add_kernel_resources(void)
88 {
89 int ret = 0;
90
91 /*
92 * The memory region of the kernel image is continuous and
93 * was reserved on setup_bootmem, register it here as a
94 * resource, with the various segments of the image as
95 * child nodes.
96 */
97
98 code_res.start = __pa_symbol(_text);
99 code_res.end = __pa_symbol(_etext) - 1;
100 code_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
101
102 rodata_res.start = __pa_symbol(__start_rodata);
103 rodata_res.end = __pa_symbol(__end_rodata) - 1;
104 rodata_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
105
106 data_res.start = __pa_symbol(_data);
107 data_res.end = __pa_symbol(_edata) - 1;
108 data_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
109
110 bss_res.start = __pa_symbol(__bss_start);
111 bss_res.end = __pa_symbol(__bss_stop) - 1;
112 bss_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
113
114 kimage_res.start = code_res.start;
115 kimage_res.end = bss_res.end;
116 kimage_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
117
118 ret = add_resource(&iomem_resource, &kimage_res);
119 if (ret < 0)
120 return ret;
121
122 ret = add_resource(&kimage_res, &code_res);
123 if (ret < 0)
124 return ret;
125
126 ret = add_resource(&kimage_res, &rodata_res);
127 if (ret < 0)
128 return ret;
129
130 ret = add_resource(&kimage_res, &data_res);
131 if (ret < 0)
132 return ret;
133
134 ret = add_resource(&kimage_res, &bss_res);
135
136 return ret;
137 }
138
init_resources(void)139 static void __init init_resources(void)
140 {
141 struct memblock_region *region = NULL;
142 struct resource *res = NULL;
143 struct resource *mem_res = NULL;
144 size_t mem_res_sz = 0;
145 int num_resources = 0, res_idx = 0, non_resv_res = 0;
146 int ret = 0;
147
148 /* + 1 as memblock_alloc() might increase memblock.reserved.cnt */
149 num_resources = memblock.memory.cnt + memblock.reserved.cnt + 1;
150 res_idx = num_resources - 1;
151
152 mem_res_sz = num_resources * sizeof(*mem_res);
153 mem_res = memblock_alloc_or_panic(mem_res_sz, SMP_CACHE_BYTES);
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_CRASH_DUMP
165 if (elfcorehdr_size > 0) {
166 elfcorehdr_res.start = elfcorehdr_addr;
167 elfcorehdr_res.end = elfcorehdr_addr + elfcorehdr_size - 1;
168 elfcorehdr_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
169 add_resource(&iomem_resource, &elfcorehdr_res);
170 }
171 #endif
172
173 for_each_reserved_mem_region(region) {
174 res = &mem_res[res_idx--];
175
176 res->name = "Reserved";
177 res->flags = IORESOURCE_MEM | IORESOURCE_EXCLUSIVE;
178 res->start = __pfn_to_phys(memblock_region_reserved_base_pfn(region));
179 res->end = __pfn_to_phys(memblock_region_reserved_end_pfn(region)) - 1;
180
181 /*
182 * Ignore any other reserved regions within
183 * system memory.
184 */
185 if (memblock_is_memory(res->start)) {
186 /* Re-use this pre-allocated resource */
187 res_idx++;
188 continue;
189 }
190
191 ret = add_resource(&iomem_resource, res);
192 if (ret < 0)
193 goto error;
194 }
195
196 /* Add /memory regions to the resource tree */
197 for_each_mem_region(region) {
198 res = &mem_res[res_idx--];
199 non_resv_res++;
200
201 if (unlikely(memblock_is_nomap(region))) {
202 res->name = "Reserved";
203 res->flags = IORESOURCE_MEM | IORESOURCE_EXCLUSIVE;
204 } else {
205 res->name = "System RAM";
206 res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
207 }
208
209 res->start = __pfn_to_phys(memblock_region_memory_base_pfn(region));
210 res->end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1;
211
212 ret = add_resource(&iomem_resource, res);
213 if (ret < 0)
214 goto error;
215 }
216
217 num_standard_resources = non_resv_res;
218 standard_resources = &mem_res[res_idx + 1];
219
220 /* Clean-up any unused pre-allocated resources */
221 if (res_idx >= 0)
222 memblock_free(mem_res, (res_idx + 1) * sizeof(*mem_res));
223 return;
224
225 error:
226 /* Better an empty resource tree than an inconsistent one */
227 release_child_resources(&iomem_resource);
228 memblock_free(mem_res, mem_res_sz);
229 }
230
reserve_memblock_reserved_regions(void)231 static int __init reserve_memblock_reserved_regions(void)
232 {
233 u64 i, j;
234
235 for (i = 0; i < num_standard_resources; i++) {
236 struct resource *mem = &standard_resources[i];
237 phys_addr_t r_start, r_end, mem_size = resource_size(mem);
238
239 if (!memblock_is_region_reserved(mem->start, mem_size))
240 continue;
241
242 for_each_reserved_mem_range(j, &r_start, &r_end) {
243 resource_size_t start, end;
244
245 start = max(PFN_PHYS(PFN_DOWN(r_start)), mem->start);
246 end = min(PFN_PHYS(PFN_UP(r_end)) - 1, mem->end);
247
248 if (start > mem->end || end < mem->start)
249 continue;
250
251 reserve_region_with_split(mem, start, end, "Reserved");
252 }
253 }
254
255 return 0;
256 }
257 arch_initcall(reserve_memblock_reserved_regions);
258
parse_dtb(void)259 static void __init parse_dtb(void)
260 {
261 /* Early scan of device tree from init memory */
262 if (early_init_dt_scan(dtb_early_va, dtb_early_pa)) {
263 const char *name = of_flat_dt_get_machine_name();
264
265 if (name) {
266 pr_info("Machine model: %s\n", name);
267 dump_stack_set_arch_desc("%s (DT)", name);
268 }
269 } else {
270 pr_err("No DTB passed to the kernel\n");
271 }
272
273 #ifdef CONFIG_CMDLINE_FORCE
274 strscpy(boot_command_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
275 pr_info("Forcing kernel command line to: %s\n", boot_command_line);
276 #endif
277 }
278
279 #if defined(CONFIG_RISCV_COMBO_SPINLOCKS)
280 DEFINE_STATIC_KEY_TRUE(qspinlock_key);
281 EXPORT_SYMBOL(qspinlock_key);
282 #endif
283
riscv_spinlock_init(void)284 static void __init riscv_spinlock_init(void)
285 {
286 char *using_ext = NULL;
287
288 if (IS_ENABLED(CONFIG_RISCV_TICKET_SPINLOCKS)) {
289 pr_info("Ticket spinlock: enabled\n");
290 return;
291 }
292
293 if (IS_ENABLED(CONFIG_RISCV_ISA_ZABHA) &&
294 IS_ENABLED(CONFIG_RISCV_ISA_ZACAS) &&
295 riscv_isa_extension_available(NULL, ZABHA) &&
296 riscv_isa_extension_available(NULL, ZACAS)) {
297 using_ext = "using Zabha";
298 } else if (riscv_isa_extension_available(NULL, ZICCRSE)) {
299 using_ext = "using Ziccrse";
300 }
301 #if defined(CONFIG_RISCV_COMBO_SPINLOCKS)
302 else {
303 static_branch_disable(&qspinlock_key);
304 pr_info("Ticket spinlock: enabled\n");
305 return;
306 }
307 #endif
308
309 if (!using_ext)
310 pr_err("Queued spinlock without Zabha or Ziccrse");
311 else
312 pr_info("Queued spinlock %s: enabled\n", using_ext);
313 }
314
315 extern void __init init_rt_signal_env(void);
316
setup_arch(char ** cmdline_p)317 void __init setup_arch(char **cmdline_p)
318 {
319 parse_dtb();
320 setup_initial_init_mm(_stext, _etext, _edata, _end);
321
322 *cmdline_p = boot_command_line;
323
324 early_ioremap_setup();
325 sbi_init();
326 jump_label_init();
327 parse_early_param();
328
329 efi_init();
330 paging_init();
331
332 /* Parse the ACPI tables for possible boot-time configuration */
333 acpi_boot_table_init();
334
335 #if IS_ENABLED(CONFIG_BUILTIN_DTB)
336 unflatten_and_copy_device_tree();
337 #else
338 unflatten_device_tree();
339 #endif
340 misc_mem_init();
341
342 init_resources();
343
344 #ifdef CONFIG_KASAN
345 kasan_init();
346 #endif
347
348 #ifdef CONFIG_SMP
349 setup_smp();
350 #endif
351
352 if (!acpi_disabled) {
353 acpi_init_rintc_map();
354 acpi_map_cpus_to_nodes();
355 }
356
357 riscv_init_cbo_blocksizes();
358 riscv_fill_hwcap();
359 apply_boot_alternatives();
360 init_rt_signal_env();
361
362 if (IS_ENABLED(CONFIG_RISCV_ISA_ZICBOM) &&
363 riscv_isa_extension_available(NULL, ZICBOM))
364 riscv_noncoherent_supported();
365 riscv_set_dma_cache_alignment();
366
367 riscv_user_isa_enable();
368 riscv_spinlock_init();
369 }
370
arch_cpu_is_hotpluggable(int cpu)371 bool arch_cpu_is_hotpluggable(int cpu)
372 {
373 return cpu_has_hotplug(cpu);
374 }
375
free_initmem(void)376 void free_initmem(void)
377 {
378 if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)) {
379 set_kernel_memory(lm_alias(__init_begin), lm_alias(__init_end), set_memory_rw_nx);
380 if (IS_ENABLED(CONFIG_64BIT))
381 set_kernel_memory(__init_begin, __init_end, set_memory_nx);
382 }
383
384 free_initmem_default(POISON_FREE_INITMEM);
385 }
386
dump_kernel_offset(struct notifier_block * self,unsigned long v,void * p)387 static int dump_kernel_offset(struct notifier_block *self,
388 unsigned long v, void *p)
389 {
390 pr_emerg("Kernel Offset: 0x%lx from 0x%lx\n",
391 kernel_map.virt_offset,
392 KERNEL_LINK_ADDR);
393
394 return 0;
395 }
396
397 static struct notifier_block kernel_offset_notifier = {
398 .notifier_call = dump_kernel_offset
399 };
400
register_kernel_offset_dumper(void)401 static int __init register_kernel_offset_dumper(void)
402 {
403 if (IS_ENABLED(CONFIG_RANDOMIZE_BASE))
404 atomic_notifier_chain_register(&panic_notifier_list,
405 &kernel_offset_notifier);
406
407 return 0;
408 }
409 device_initcall(register_kernel_offset_dumper);
410