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