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 #ifdef CONFIG_XIP_KERNEL
51 = ATOMIC_INIT(0xC001BEEF)
52 #endif
53 ;
54 unsigned long boot_cpu_hartid;
55 EXPORT_SYMBOL_GPL(boot_cpu_hartid);
56
57 /*
58 * Place kernel memory regions on the resource tree so that
59 * kexec-tools can retrieve them from /proc/iomem. While there
60 * also add "System RAM" regions for compatibility with other
61 * archs, and the rest of the known regions for completeness.
62 */
63 static struct resource kimage_res = { .name = "Kernel image", };
64 static struct resource code_res = { .name = "Kernel code", };
65 static struct resource data_res = { .name = "Kernel data", };
66 static struct resource rodata_res = { .name = "Kernel rodata", };
67 static struct resource bss_res = { .name = "Kernel bss", };
68 #ifdef CONFIG_CRASH_DUMP
69 static struct resource elfcorehdr_res = { .name = "ELF Core hdr", };
70 #endif
71
72 static int num_standard_resources;
73 static struct resource *standard_resources;
74
add_resource(struct resource * parent,struct resource * res)75 static int __init add_resource(struct resource *parent,
76 struct resource *res)
77 {
78 int ret = 0;
79
80 ret = insert_resource(parent, res);
81 if (ret < 0) {
82 pr_err("Failed to add a %s resource at %llx\n",
83 res->name, (unsigned long long) res->start);
84 return ret;
85 }
86
87 return 1;
88 }
89
add_kernel_resources(void)90 static int __init add_kernel_resources(void)
91 {
92 int ret = 0;
93
94 /*
95 * The memory region of the kernel image is continuous and
96 * was reserved on setup_bootmem, register it here as a
97 * resource, with the various segments of the image as
98 * child nodes.
99 */
100
101 code_res.start = __pa_symbol(_text);
102 code_res.end = __pa_symbol(_etext) - 1;
103 code_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
104
105 rodata_res.start = __pa_symbol(__start_rodata);
106 rodata_res.end = __pa_symbol(__end_rodata) - 1;
107 rodata_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
108
109 data_res.start = __pa_symbol(_data);
110 data_res.end = __pa_symbol(_edata) - 1;
111 data_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
112
113 bss_res.start = __pa_symbol(__bss_start);
114 bss_res.end = __pa_symbol(__bss_stop) - 1;
115 bss_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
116
117 kimage_res.start = code_res.start;
118 kimage_res.end = bss_res.end;
119 kimage_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
120
121 ret = add_resource(&iomem_resource, &kimage_res);
122 if (ret < 0)
123 return ret;
124
125 ret = add_resource(&kimage_res, &code_res);
126 if (ret < 0)
127 return ret;
128
129 ret = add_resource(&kimage_res, &rodata_res);
130 if (ret < 0)
131 return ret;
132
133 ret = add_resource(&kimage_res, &data_res);
134 if (ret < 0)
135 return ret;
136
137 ret = add_resource(&kimage_res, &bss_res);
138
139 return ret;
140 }
141
init_resources(void)142 static void __init init_resources(void)
143 {
144 struct memblock_region *region = NULL;
145 struct resource *res = NULL;
146 struct resource *mem_res = NULL;
147 size_t mem_res_sz = 0;
148 int num_resources = 0, res_idx = 0, non_resv_res = 0;
149 int ret = 0;
150
151 /* + 1 as memblock_alloc() might increase memblock.reserved.cnt */
152 num_resources = memblock.memory.cnt + memblock.reserved.cnt + 1;
153 res_idx = num_resources - 1;
154
155 mem_res_sz = num_resources * sizeof(*mem_res);
156 mem_res = memblock_alloc_or_panic(mem_res_sz, SMP_CACHE_BYTES);
157
158 /*
159 * Start by adding the reserved regions, if they overlap
160 * with /memory regions, insert_resource later on will take
161 * care of it.
162 */
163 ret = add_kernel_resources();
164 if (ret < 0)
165 goto error;
166
167 #ifdef CONFIG_CRASH_DUMP
168 if (elfcorehdr_size > 0) {
169 elfcorehdr_res.start = elfcorehdr_addr;
170 elfcorehdr_res.end = elfcorehdr_addr + elfcorehdr_size - 1;
171 elfcorehdr_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
172 add_resource(&iomem_resource, &elfcorehdr_res);
173 }
174 #endif
175
176 for_each_reserved_mem_region(region) {
177 res = &mem_res[res_idx--];
178
179 res->name = "Reserved";
180 res->flags = IORESOURCE_MEM | IORESOURCE_EXCLUSIVE;
181 res->start = __pfn_to_phys(memblock_region_reserved_base_pfn(region));
182 res->end = __pfn_to_phys(memblock_region_reserved_end_pfn(region)) - 1;
183
184 /*
185 * Ignore any other reserved regions within
186 * system memory.
187 */
188 if (memblock_is_memory(res->start)) {
189 /* Re-use this pre-allocated resource */
190 res_idx++;
191 continue;
192 }
193
194 ret = add_resource(&iomem_resource, res);
195 if (ret < 0)
196 goto error;
197 }
198
199 /* Add /memory regions to the resource tree */
200 for_each_mem_region(region) {
201 res = &mem_res[res_idx--];
202 non_resv_res++;
203
204 if (unlikely(memblock_is_nomap(region))) {
205 res->name = "Reserved";
206 res->flags = IORESOURCE_MEM | IORESOURCE_EXCLUSIVE;
207 } else {
208 res->name = "System RAM";
209 res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
210 }
211
212 res->start = __pfn_to_phys(memblock_region_memory_base_pfn(region));
213 res->end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1;
214
215 ret = add_resource(&iomem_resource, res);
216 if (ret < 0)
217 goto error;
218 }
219
220 num_standard_resources = non_resv_res;
221 standard_resources = &mem_res[res_idx + 1];
222
223 /* Clean-up any unused pre-allocated resources */
224 if (res_idx >= 0)
225 memblock_free(mem_res, (res_idx + 1) * sizeof(*mem_res));
226 return;
227
228 error:
229 /* Better an empty resource tree than an inconsistent one */
230 release_child_resources(&iomem_resource);
231 memblock_free(mem_res, mem_res_sz);
232 }
233
reserve_memblock_reserved_regions(void)234 static int __init reserve_memblock_reserved_regions(void)
235 {
236 u64 i, j;
237
238 for (i = 0; i < num_standard_resources; i++) {
239 struct resource *mem = &standard_resources[i];
240 phys_addr_t r_start, r_end, mem_size = resource_size(mem);
241
242 if (!memblock_is_region_reserved(mem->start, mem_size))
243 continue;
244
245 for_each_reserved_mem_range(j, &r_start, &r_end) {
246 resource_size_t start, end;
247
248 start = max(PFN_PHYS(PFN_DOWN(r_start)), mem->start);
249 end = min(PFN_PHYS(PFN_UP(r_end)) - 1, mem->end);
250
251 if (start > mem->end || end < mem->start)
252 continue;
253
254 reserve_region_with_split(mem, start, end, "Reserved");
255 }
256 }
257
258 return 0;
259 }
260 arch_initcall(reserve_memblock_reserved_regions);
261
parse_dtb(void)262 static void __init parse_dtb(void)
263 {
264 /* Early scan of device tree from init memory */
265 if (early_init_dt_scan(dtb_early_va, dtb_early_pa)) {
266 const char *name = of_flat_dt_get_machine_name();
267
268 if (name) {
269 pr_info("Machine model: %s\n", name);
270 dump_stack_set_arch_desc("%s (DT)", name);
271 }
272 } else {
273 pr_err("No DTB passed to the kernel\n");
274 }
275 }
276
277 #if defined(CONFIG_RISCV_COMBO_SPINLOCKS)
278 DEFINE_STATIC_KEY_TRUE(qspinlock_key);
279 EXPORT_SYMBOL(qspinlock_key);
280 #endif
281
riscv_spinlock_init(void)282 static void __init riscv_spinlock_init(void)
283 {
284 char *using_ext = NULL;
285
286 if (IS_ENABLED(CONFIG_RISCV_TICKET_SPINLOCKS)) {
287 pr_info("Ticket spinlock: enabled\n");
288 return;
289 }
290
291 if (IS_ENABLED(CONFIG_RISCV_ISA_ZABHA) &&
292 IS_ENABLED(CONFIG_RISCV_ISA_ZACAS) &&
293 riscv_isa_extension_available(NULL, ZABHA) &&
294 riscv_isa_extension_available(NULL, ZACAS)) {
295 using_ext = "using Zabha";
296 } else if (riscv_isa_extension_available(NULL, ZICCRSE)) {
297 using_ext = "using Ziccrse";
298 }
299 #if defined(CONFIG_RISCV_COMBO_SPINLOCKS)
300 else {
301 static_branch_disable(&qspinlock_key);
302 pr_info("Ticket spinlock: enabled\n");
303 return;
304 }
305 #endif
306
307 if (!using_ext)
308 pr_err("Queued spinlock without Zabha or Ziccrse");
309 else
310 pr_info("Queued spinlock %s: enabled\n", using_ext);
311 }
312
313 extern void __init init_rt_signal_env(void);
314
setup_arch(char ** cmdline_p)315 void __init setup_arch(char **cmdline_p)
316 {
317 parse_dtb();
318 setup_initial_init_mm(_stext, _etext, _edata, _end);
319
320 *cmdline_p = boot_command_line;
321
322 early_ioremap_setup();
323 sbi_init();
324 jump_label_init();
325 parse_early_param();
326
327 efi_init();
328 paging_init();
329
330 /* Parse the ACPI tables for possible boot-time configuration */
331 acpi_boot_table_init();
332
333 #if IS_ENABLED(CONFIG_BUILTIN_DTB)
334 unflatten_and_copy_device_tree();
335 #else
336 unflatten_device_tree();
337 #endif
338 misc_mem_init();
339
340 init_resources();
341
342 #ifdef CONFIG_KASAN
343 kasan_init();
344 #endif
345
346 #ifdef CONFIG_SMP
347 setup_smp();
348 #endif
349
350 if (!acpi_disabled) {
351 acpi_init_rintc_map();
352 acpi_map_cpus_to_nodes();
353 }
354
355 riscv_init_cbo_blocksizes();
356 riscv_fill_hwcap();
357 apply_boot_alternatives();
358 init_rt_signal_env();
359
360 if (IS_ENABLED(CONFIG_RISCV_ISA_ZICBOM) &&
361 riscv_isa_extension_available(NULL, ZICBOM))
362 riscv_noncoherent_supported();
363 riscv_set_dma_cache_alignment();
364
365 riscv_user_isa_enable();
366 riscv_spinlock_init();
367
368 if (!IS_ENABLED(CONFIG_RISCV_ISA_ZBB) || !riscv_isa_extension_available(NULL, ZBB))
369 static_branch_disable(&efficient_ffs_key);
370 }
371
arch_cpu_is_hotpluggable(int cpu)372 bool arch_cpu_is_hotpluggable(int cpu)
373 {
374 return cpu_has_hotplug(cpu);
375 }
376
free_initmem(void)377 void free_initmem(void)
378 {
379 if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)) {
380 set_kernel_memory(lm_alias(__init_begin), lm_alias(__init_end), set_memory_rw_nx);
381 if (IS_ENABLED(CONFIG_64BIT))
382 set_kernel_memory(__init_begin, __init_end, set_memory_nx);
383 }
384
385 free_initmem_default(POISON_FREE_INITMEM);
386 }
387
dump_kernel_offset(struct notifier_block * self,unsigned long v,void * p)388 static int dump_kernel_offset(struct notifier_block *self,
389 unsigned long v, void *p)
390 {
391 pr_emerg("Kernel Offset: 0x%lx from 0x%lx\n",
392 kernel_map.virt_offset,
393 KERNEL_LINK_ADDR);
394
395 return 0;
396 }
397
398 static struct notifier_block kernel_offset_notifier = {
399 .notifier_call = dump_kernel_offset
400 };
401
register_kernel_offset_dumper(void)402 static int __init register_kernel_offset_dumper(void)
403 {
404 if (IS_ENABLED(CONFIG_RANDOMIZE_BASE))
405 atomic_notifier_chain_register(&panic_notifier_list,
406 &kernel_offset_notifier);
407
408 return 0;
409 }
410 device_initcall(register_kernel_offset_dumper);
411