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/init.h>
12 #include <linux/mm.h>
13 #include <linux/memblock.h>
14 #include <linux/sched.h>
15 #include <linux/console.h>
16 #include <linux/screen_info.h>
17 #include <linux/of_fdt.h>
18 #include <linux/of_platform.h>
19 #include <linux/sched/task.h>
20 #include <linux/smp.h>
21 #include <linux/efi.h>
22 #include <linux/crash_dump.h>
23
24 #include <asm/alternative.h>
25 #include <asm/cacheflush.h>
26 #include <asm/cpu_ops.h>
27 #include <asm/early_ioremap.h>
28 #include <asm/pgtable.h>
29 #include <asm/setup.h>
30 #include <asm/set_memory.h>
31 #include <asm/sections.h>
32 #include <asm/sbi.h>
33 #include <asm/tlbflush.h>
34 #include <asm/thread_info.h>
35 #include <asm/kasan.h>
36 #include <asm/efi.h>
37
38 #include "head.h"
39
40 #if defined(CONFIG_DUMMY_CONSOLE) || defined(CONFIG_EFI)
41 struct screen_info screen_info __section(".data") = {
42 .orig_video_lines = 30,
43 .orig_video_cols = 80,
44 .orig_video_mode = 0,
45 .orig_video_ega_bx = 0,
46 .orig_video_isVGA = 1,
47 .orig_video_points = 8
48 };
49 #endif
50
51 /*
52 * The lucky hart to first increment this variable will boot the other cores.
53 * This is used before the kernel initializes the BSS so it can't be in the
54 * BSS.
55 */
56 atomic_t hart_lottery __section(".sdata")
57 #ifdef CONFIG_XIP_KERNEL
58 = ATOMIC_INIT(0xC001BEEF)
59 #endif
60 ;
61 unsigned long boot_cpu_hartid;
62 static DEFINE_PER_CPU(struct cpu, cpu_devices);
63
64 /*
65 * Place kernel memory regions on the resource tree so that
66 * kexec-tools can retrieve them from /proc/iomem. While there
67 * also add "System RAM" regions for compatibility with other
68 * archs, and the rest of the known regions for completeness.
69 */
70 static struct resource kimage_res = { .name = "Kernel image", };
71 static struct resource code_res = { .name = "Kernel code", };
72 static struct resource data_res = { .name = "Kernel data", };
73 static struct resource rodata_res = { .name = "Kernel rodata", };
74 static struct resource bss_res = { .name = "Kernel bss", };
75 #ifdef CONFIG_CRASH_DUMP
76 static struct resource elfcorehdr_res = { .name = "ELF Core hdr", };
77 #endif
78
add_resource(struct resource * parent,struct resource * res)79 static int __init add_resource(struct resource *parent,
80 struct resource *res)
81 {
82 int ret = 0;
83
84 ret = insert_resource(parent, res);
85 if (ret < 0) {
86 pr_err("Failed to add a %s resource at %llx\n",
87 res->name, (unsigned long long) res->start);
88 return ret;
89 }
90
91 return 1;
92 }
93
add_kernel_resources(void)94 static int __init add_kernel_resources(void)
95 {
96 int ret = 0;
97
98 /*
99 * The memory region of the kernel image is continuous and
100 * was reserved on setup_bootmem, register it here as a
101 * resource, with the various segments of the image as
102 * child nodes.
103 */
104
105 code_res.start = __pa_symbol(_text);
106 code_res.end = __pa_symbol(_etext) - 1;
107 code_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
108
109 rodata_res.start = __pa_symbol(__start_rodata);
110 rodata_res.end = __pa_symbol(__end_rodata) - 1;
111 rodata_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
112
113 data_res.start = __pa_symbol(_data);
114 data_res.end = __pa_symbol(_edata) - 1;
115 data_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
116
117 bss_res.start = __pa_symbol(__bss_start);
118 bss_res.end = __pa_symbol(__bss_stop) - 1;
119 bss_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
120
121 kimage_res.start = code_res.start;
122 kimage_res.end = bss_res.end;
123 kimage_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
124
125 ret = add_resource(&iomem_resource, &kimage_res);
126 if (ret < 0)
127 return ret;
128
129 ret = add_resource(&kimage_res, &code_res);
130 if (ret < 0)
131 return ret;
132
133 ret = add_resource(&kimage_res, &rodata_res);
134 if (ret < 0)
135 return ret;
136
137 ret = add_resource(&kimage_res, &data_res);
138 if (ret < 0)
139 return ret;
140
141 ret = add_resource(&kimage_res, &bss_res);
142
143 return ret;
144 }
145
init_resources(void)146 static void __init init_resources(void)
147 {
148 struct memblock_region *region = NULL;
149 struct resource *res = NULL;
150 struct resource *mem_res = NULL;
151 size_t mem_res_sz = 0;
152 int num_resources = 0, res_idx = 0;
153 int ret = 0;
154
155 /* + 1 as memblock_alloc() might increase memblock.reserved.cnt */
156 num_resources = memblock.memory.cnt + memblock.reserved.cnt + 1;
157 res_idx = num_resources - 1;
158
159 mem_res_sz = num_resources * sizeof(*mem_res);
160 mem_res = memblock_alloc(mem_res_sz, SMP_CACHE_BYTES);
161 if (!mem_res)
162 panic("%s: Failed to allocate %zu bytes\n", __func__, mem_res_sz);
163
164 /*
165 * Start by adding the reserved regions, if they overlap
166 * with /memory regions, insert_resource later on will take
167 * care of it.
168 */
169 ret = add_kernel_resources();
170 if (ret < 0)
171 goto error;
172
173 #ifdef CONFIG_KEXEC_CORE
174 if (crashk_res.start != crashk_res.end) {
175 ret = add_resource(&iomem_resource, &crashk_res);
176 if (ret < 0)
177 goto error;
178 }
179 #endif
180
181 #ifdef CONFIG_CRASH_DUMP
182 if (elfcorehdr_size > 0) {
183 elfcorehdr_res.start = elfcorehdr_addr;
184 elfcorehdr_res.end = elfcorehdr_addr + elfcorehdr_size - 1;
185 elfcorehdr_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
186 add_resource(&iomem_resource, &elfcorehdr_res);
187 }
188 #endif
189
190 for_each_reserved_mem_region(region) {
191 res = &mem_res[res_idx--];
192
193 res->name = "Reserved";
194 res->flags = IORESOURCE_MEM | IORESOURCE_EXCLUSIVE;
195 res->start = __pfn_to_phys(memblock_region_reserved_base_pfn(region));
196 res->end = __pfn_to_phys(memblock_region_reserved_end_pfn(region)) - 1;
197
198 /*
199 * Ignore any other reserved regions within
200 * system memory.
201 */
202 if (memblock_is_memory(res->start)) {
203 /* Re-use this pre-allocated resource */
204 res_idx++;
205 continue;
206 }
207
208 ret = add_resource(&iomem_resource, res);
209 if (ret < 0)
210 goto error;
211 }
212
213 /* Add /memory regions to the resource tree */
214 for_each_mem_region(region) {
215 res = &mem_res[res_idx--];
216
217 if (unlikely(memblock_is_nomap(region))) {
218 res->name = "Reserved";
219 res->flags = IORESOURCE_MEM | IORESOURCE_EXCLUSIVE;
220 } else {
221 res->name = "System RAM";
222 res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
223 }
224
225 res->start = __pfn_to_phys(memblock_region_memory_base_pfn(region));
226 res->end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1;
227
228 ret = add_resource(&iomem_resource, res);
229 if (ret < 0)
230 goto error;
231 }
232
233 /* Clean-up any unused pre-allocated resources */
234 if (res_idx >= 0)
235 memblock_free(mem_res, (res_idx + 1) * sizeof(*mem_res));
236 return;
237
238 error:
239 /* Better an empty resource tree than an inconsistent one */
240 release_child_resources(&iomem_resource);
241 memblock_free(mem_res, mem_res_sz);
242 }
243
244
parse_dtb(void)245 static void __init parse_dtb(void)
246 {
247 /* Early scan of device tree from init memory */
248 if (early_init_dt_scan(dtb_early_va)) {
249 const char *name = of_flat_dt_get_machine_name();
250
251 if (name) {
252 pr_info("Machine model: %s\n", name);
253 dump_stack_set_arch_desc("%s (DT)", name);
254 }
255 } else {
256 pr_err("No DTB passed to the kernel\n");
257 }
258
259 #ifdef CONFIG_CMDLINE_FORCE
260 strscpy(boot_command_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
261 pr_info("Forcing kernel command line to: %s\n", boot_command_line);
262 #endif
263 }
264
setup_arch(char ** cmdline_p)265 void __init setup_arch(char **cmdline_p)
266 {
267 parse_dtb();
268 setup_initial_init_mm(_stext, _etext, _edata, _end);
269
270 *cmdline_p = boot_command_line;
271
272 early_ioremap_setup();
273 jump_label_init();
274 parse_early_param();
275
276 efi_init();
277 paging_init();
278 #if IS_ENABLED(CONFIG_BUILTIN_DTB)
279 unflatten_and_copy_device_tree();
280 #else
281 if (early_init_dt_verify(__va(XIP_FIXUP(dtb_early_pa))))
282 unflatten_device_tree();
283 else
284 pr_err("No DTB found in kernel mappings\n");
285 #endif
286 early_init_fdt_scan_reserved_mem();
287 misc_mem_init();
288
289 init_resources();
290 sbi_init();
291
292 #ifdef CONFIG_KASAN
293 kasan_init();
294 #endif
295
296 #ifdef CONFIG_SMP
297 setup_smp();
298 #endif
299
300 riscv_init_cbom_blocksize();
301 riscv_fill_hwcap();
302 apply_boot_alternatives();
303 if (IS_ENABLED(CONFIG_RISCV_ISA_ZICBOM) &&
304 riscv_isa_extension_available(NULL, ZICBOM))
305 riscv_noncoherent_supported();
306 }
307
topology_init(void)308 static int __init topology_init(void)
309 {
310 int i, ret;
311
312 for_each_possible_cpu(i) {
313 struct cpu *cpu = &per_cpu(cpu_devices, i);
314
315 cpu->hotpluggable = cpu_has_hotplug(i);
316 ret = register_cpu(cpu, i);
317 if (unlikely(ret))
318 pr_warn("Warning: %s: register_cpu %d failed (%d)\n",
319 __func__, i, ret);
320 }
321
322 return 0;
323 }
324 subsys_initcall(topology_init);
325
free_initmem(void)326 void free_initmem(void)
327 {
328 if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)) {
329 set_kernel_memory(lm_alias(__init_begin), lm_alias(__init_end), set_memory_rw_nx);
330 if (IS_ENABLED(CONFIG_64BIT))
331 set_kernel_memory(__init_begin, __init_end, set_memory_nx);
332 }
333
334 free_initmem_default(POISON_FREE_INITMEM);
335 }
336