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 #include <linux/jump_label.h>
25 #include <linux/gcd.h>
26
27 #include <asm/acpi.h>
28 #include <asm/alternative.h>
29 #include <asm/cacheflush.h>
30 #include <asm/cpufeature.h>
31 #include <asm/early_ioremap.h>
32 #include <asm/pgtable.h>
33 #include <asm/setup.h>
34 #include <asm/set_memory.h>
35 #include <asm/sections.h>
36 #include <asm/sbi.h>
37 #include <asm/tlbflush.h>
38 #include <asm/thread_info.h>
39 #include <asm/kasan.h>
40 #include <asm/efi.h>
41
42 #include "head.h"
43
44 /*
45 * The lucky hart to first increment this variable will boot the other cores.
46 * This is used before the kernel initializes the BSS so it can't be in the
47 * BSS.
48 */
49 atomic_t hart_lottery __section(".sdata");
50 unsigned long boot_cpu_hartid;
51 EXPORT_SYMBOL_GPL(boot_cpu_hartid);
52
53 /*
54 * Place kernel memory regions on the resource tree so that
55 * kexec-tools can retrieve them from /proc/iomem. While there
56 * also add "System RAM" regions for compatibility with other
57 * archs, and the rest of the known regions for completeness.
58 */
59 static struct resource kimage_res = { .name = "Kernel image", };
60 static struct resource code_res = { .name = "Kernel code", };
61 static struct resource data_res = { .name = "Kernel data", };
62 static struct resource rodata_res = { .name = "Kernel rodata", };
63 static struct resource bss_res = { .name = "Kernel bss", };
64 #ifdef CONFIG_CRASH_DUMP
65 static struct resource elfcorehdr_res = { .name = "ELF Core hdr", };
66 #endif
67
68 static int num_standard_resources;
69 static struct resource *standard_resources;
70
add_resource(struct resource * parent,struct resource * res)71 static int __init add_resource(struct resource *parent,
72 struct resource *res)
73 {
74 int ret;
75
76 ret = insert_resource(parent, res);
77 if (ret < 0)
78 pr_err("Failed to add resource %s %pR\n", res->name, res);
79
80 return ret;
81 }
82
add_kernel_resources(void)83 static int __init add_kernel_resources(void)
84 {
85 int ret = 0;
86
87 /*
88 * The memory region of the kernel image is continuous and
89 * was reserved on setup_bootmem, register it here as a
90 * resource, with the various segments of the image as
91 * child nodes.
92 */
93
94 code_res.start = __pa_symbol(_text);
95 code_res.end = __pa_symbol(_etext) - 1;
96 code_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
97
98 rodata_res.start = __pa_symbol(__start_rodata);
99 rodata_res.end = __pa_symbol(__end_rodata) - 1;
100 rodata_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
101
102 data_res.start = __pa_symbol(_data);
103 data_res.end = __pa_symbol(_edata) - 1;
104 data_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
105
106 bss_res.start = __pa_symbol(__bss_start);
107 bss_res.end = __pa_symbol(__bss_stop) - 1;
108 bss_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
109
110 kimage_res.start = code_res.start;
111 kimage_res.end = bss_res.end;
112 kimage_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
113
114 ret = add_resource(&iomem_resource, &kimage_res);
115 if (ret < 0)
116 return ret;
117
118 ret = add_resource(&kimage_res, &code_res);
119 if (ret < 0)
120 return ret;
121
122 ret = add_resource(&kimage_res, &rodata_res);
123 if (ret < 0)
124 return ret;
125
126 ret = add_resource(&kimage_res, &data_res);
127 if (ret < 0)
128 return ret;
129
130 ret = add_resource(&kimage_res, &bss_res);
131
132 return ret;
133 }
134
init_resources(void)135 static void __init init_resources(void)
136 {
137 struct memblock_region *region = NULL;
138 struct resource *res = NULL;
139 struct resource *mem_res = NULL;
140 size_t mem_res_sz = 0;
141 int num_resources = 0, res_idx = 0, non_resv_res = 0;
142 int ret = 0;
143
144 /* + 1 as memblock_alloc() might increase memblock.reserved.cnt */
145 num_resources = memblock.memory.cnt + memblock.reserved.cnt + 1;
146 res_idx = num_resources - 1;
147
148 mem_res_sz = num_resources * sizeof(*mem_res);
149 mem_res = memblock_alloc_or_panic(mem_res_sz, SMP_CACHE_BYTES);
150
151 /*
152 * Start by adding the reserved regions, if they overlap
153 * with /memory regions, insert_resource later on will take
154 * care of it.
155 */
156 ret = add_kernel_resources();
157 if (ret < 0)
158 goto error;
159
160 #ifdef CONFIG_CRASH_DUMP
161 if (elfcorehdr_size > 0) {
162 elfcorehdr_res.start = elfcorehdr_addr;
163 elfcorehdr_res.end = elfcorehdr_addr + elfcorehdr_size - 1;
164 elfcorehdr_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
165 add_resource(&iomem_resource, &elfcorehdr_res);
166 }
167 #endif
168
169 for_each_reserved_mem_region(region) {
170 res = &mem_res[res_idx--];
171
172 res->name = "Reserved";
173 res->flags = IORESOURCE_MEM | IORESOURCE_EXCLUSIVE;
174 res->start = __pfn_to_phys(memblock_region_reserved_base_pfn(region));
175 res->end = __pfn_to_phys(memblock_region_reserved_end_pfn(region)) - 1;
176
177 /*
178 * Ignore any other reserved regions within
179 * system memory.
180 */
181 if (memblock_is_memory(res->start)) {
182 /* Re-use this pre-allocated resource */
183 res_idx++;
184 continue;
185 }
186
187 ret = add_resource(&iomem_resource, res);
188 if (ret < 0)
189 goto error;
190 }
191
192 /* Add /memory regions to the resource tree */
193 for_each_mem_region(region) {
194 res = &mem_res[res_idx--];
195 non_resv_res++;
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 num_standard_resources = non_resv_res;
214 standard_resources = &mem_res[res_idx + 1];
215
216 /* Clean-up any unused pre-allocated resources */
217 if (res_idx >= 0)
218 memblock_free(mem_res, (res_idx + 1) * sizeof(*mem_res));
219 return;
220
221 error:
222 /* Better an empty resource tree than an inconsistent one */
223 release_child_resources(&iomem_resource);
224 memblock_free(mem_res, mem_res_sz);
225 }
226
reserve_memblock_reserved_regions(void)227 static int __init reserve_memblock_reserved_regions(void)
228 {
229 u64 i, j;
230
231 for (i = 0; i < num_standard_resources; i++) {
232 struct resource *mem = &standard_resources[i];
233 phys_addr_t r_start, r_end, mem_size = resource_size(mem);
234
235 if (!memblock_is_region_reserved(mem->start, mem_size))
236 continue;
237
238 for_each_reserved_mem_range(j, &r_start, &r_end) {
239 resource_size_t start, end;
240
241 start = max(PFN_PHYS(PFN_DOWN(r_start)), mem->start);
242 end = min(PFN_PHYS(PFN_UP(r_end)) - 1, mem->end);
243
244 if (start > mem->end || end < mem->start)
245 continue;
246
247 reserve_region_with_split(mem, start, end, "Reserved");
248 }
249 }
250
251 return 0;
252 }
253 arch_initcall(reserve_memblock_reserved_regions);
254
parse_dtb(void)255 static void __init parse_dtb(void)
256 {
257 /* Early scan of device tree from init memory */
258 if (early_init_dt_scan(dtb_early_va, dtb_early_pa)) {
259 const char *name = of_flat_dt_get_machine_name();
260
261 if (name) {
262 pr_info("Machine model: %s\n", name);
263 dump_stack_set_arch_desc("%s (DT)", name);
264 }
265 } else {
266 pr_err("No DTB passed to the kernel\n");
267 }
268 }
269
270 #if defined(CONFIG_RISCV_COMBO_SPINLOCKS)
271 DEFINE_STATIC_KEY_TRUE(qspinlock_key);
272 EXPORT_SYMBOL(qspinlock_key);
273 #endif
274
riscv_spinlock_init(void)275 static void __init riscv_spinlock_init(void)
276 {
277 char *using_ext = NULL;
278
279 if (IS_ENABLED(CONFIG_RISCV_TICKET_SPINLOCKS)) {
280 pr_info("Ticket spinlock: enabled\n");
281 return;
282 }
283
284 if (IS_ENABLED(CONFIG_RISCV_ISA_ZABHA) &&
285 IS_ENABLED(CONFIG_RISCV_ISA_ZACAS) &&
286 IS_ENABLED(CONFIG_TOOLCHAIN_HAS_ZACAS) &&
287 riscv_isa_extension_available(NULL, ZABHA) &&
288 riscv_isa_extension_available(NULL, ZACAS)) {
289 using_ext = "using Zabha";
290 } else if (riscv_isa_extension_available(NULL, ZICCRSE)) {
291 using_ext = "using Ziccrse";
292 }
293 #if defined(CONFIG_RISCV_COMBO_SPINLOCKS)
294 else {
295 static_branch_disable(&qspinlock_key);
296 pr_info("Ticket spinlock: enabled\n");
297 return;
298 }
299 #endif
300
301 if (!using_ext)
302 pr_err("Queued spinlock without Zabha or Ziccrse");
303 else
304 pr_info("Queued spinlock %s: enabled\n", using_ext);
305 }
306
307 extern void __init init_rt_signal_env(void);
308
setup_arch(char ** cmdline_p)309 void __init setup_arch(char **cmdline_p)
310 {
311 parse_dtb();
312 setup_initial_init_mm(_stext, _etext, _edata, _end);
313
314 *cmdline_p = boot_command_line;
315
316 early_ioremap_setup();
317 sbi_init();
318 jump_label_init();
319 parse_early_param();
320
321 efi_init();
322 paging_init();
323
324 acpi_table_upgrade();
325
326 /* Parse the ACPI tables for possible boot-time configuration */
327 acpi_boot_table_init();
328
329 if (acpi_disabled) {
330 #if IS_ENABLED(CONFIG_BUILTIN_DTB)
331 unflatten_and_copy_device_tree();
332 #else
333 unflatten_device_tree();
334 #endif
335 }
336
337 misc_mem_init();
338
339 init_resources();
340
341 #ifdef CONFIG_KASAN
342 kasan_init();
343 #endif
344
345 #ifdef CONFIG_SMP
346 setup_smp();
347 #endif
348
349 if (!acpi_disabled) {
350 acpi_init_rintc_map();
351 acpi_map_cpus_to_nodes();
352 }
353
354 riscv_init_cbo_blocksizes();
355 riscv_fill_hwcap();
356 apply_boot_alternatives();
357 init_rt_signal_env();
358
359 if (IS_ENABLED(CONFIG_RISCV_ISA_ZICBOM) &&
360 riscv_isa_extension_available(NULL, ZICBOM))
361 riscv_noncoherent_supported();
362 riscv_set_dma_cache_alignment();
363
364 riscv_user_isa_enable();
365 riscv_spinlock_init();
366
367 if (!IS_ENABLED(CONFIG_RISCV_ISA_ZBB) || !riscv_isa_extension_available(NULL, ZBB))
368 static_branch_disable(&efficient_ffs_key);
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