xref: /openbmc/linux/arch/riscv/kernel/setup.c (revision 046b212a)
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/screen_info.h>
19 #include <linux/of_fdt.h>
20 #include <linux/sched/task.h>
21 #include <linux/smp.h>
22 #include <linux/efi.h>
23 #include <linux/crash_dump.h>
24 #include <linux/panic_notifier.h>
25 
26 #include <asm/acpi.h>
27 #include <asm/alternative.h>
28 #include <asm/cacheflush.h>
29 #include <asm/cpu_ops.h>
30 #include <asm/early_ioremap.h>
31 #include <asm/pgtable.h>
32 #include <asm/setup.h>
33 #include <asm/set_memory.h>
34 #include <asm/sections.h>
35 #include <asm/sbi.h>
36 #include <asm/tlbflush.h>
37 #include <asm/thread_info.h>
38 #include <asm/kasan.h>
39 #include <asm/efi.h>
40 
41 #include "head.h"
42 
43 #if defined(CONFIG_DUMMY_CONSOLE) || defined(CONFIG_EFI)
44 struct screen_info screen_info __section(".data") = {
45 	.orig_video_lines	= 30,
46 	.orig_video_cols	= 80,
47 	.orig_video_mode	= 0,
48 	.orig_video_ega_bx	= 0,
49 	.orig_video_isVGA	= 1,
50 	.orig_video_points	= 8
51 };
52 #endif
53 
54 /*
55  * The lucky hart to first increment this variable will boot the other cores.
56  * This is used before the kernel initializes the BSS so it can't be in the
57  * BSS.
58  */
59 atomic_t hart_lottery __section(".sdata")
60 #ifdef CONFIG_XIP_KERNEL
61 = ATOMIC_INIT(0xC001BEEF)
62 #endif
63 ;
64 unsigned long boot_cpu_hartid;
65 static DEFINE_PER_CPU(struct cpu, cpu_devices);
66 
67 /*
68  * Place kernel memory regions on the resource tree so that
69  * kexec-tools can retrieve them from /proc/iomem. While there
70  * also add "System RAM" regions for compatibility with other
71  * archs, and the rest of the known regions for completeness.
72  */
73 static struct resource kimage_res = { .name = "Kernel image", };
74 static struct resource code_res = { .name = "Kernel code", };
75 static struct resource data_res = { .name = "Kernel data", };
76 static struct resource rodata_res = { .name = "Kernel rodata", };
77 static struct resource bss_res = { .name = "Kernel bss", };
78 #ifdef CONFIG_CRASH_DUMP
79 static struct resource elfcorehdr_res = { .name = "ELF Core hdr", };
80 #endif
81 
82 static int __init add_resource(struct resource *parent,
83 				struct resource *res)
84 {
85 	int ret = 0;
86 
87 	ret = insert_resource(parent, res);
88 	if (ret < 0) {
89 		pr_err("Failed to add a %s resource at %llx\n",
90 			res->name, (unsigned long long) res->start);
91 		return ret;
92 	}
93 
94 	return 1;
95 }
96 
97 static int __init add_kernel_resources(void)
98 {
99 	int ret = 0;
100 
101 	/*
102 	 * The memory region of the kernel image is continuous and
103 	 * was reserved on setup_bootmem, register it here as a
104 	 * resource, with the various segments of the image as
105 	 * child nodes.
106 	 */
107 
108 	code_res.start = __pa_symbol(_text);
109 	code_res.end = __pa_symbol(_etext) - 1;
110 	code_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
111 
112 	rodata_res.start = __pa_symbol(__start_rodata);
113 	rodata_res.end = __pa_symbol(__end_rodata) - 1;
114 	rodata_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
115 
116 	data_res.start = __pa_symbol(_data);
117 	data_res.end = __pa_symbol(_edata) - 1;
118 	data_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
119 
120 	bss_res.start = __pa_symbol(__bss_start);
121 	bss_res.end = __pa_symbol(__bss_stop) - 1;
122 	bss_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
123 
124 	kimage_res.start = code_res.start;
125 	kimage_res.end = bss_res.end;
126 	kimage_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
127 
128 	ret = add_resource(&iomem_resource, &kimage_res);
129 	if (ret < 0)
130 		return ret;
131 
132 	ret = add_resource(&kimage_res, &code_res);
133 	if (ret < 0)
134 		return ret;
135 
136 	ret = add_resource(&kimage_res, &rodata_res);
137 	if (ret < 0)
138 		return ret;
139 
140 	ret = add_resource(&kimage_res, &data_res);
141 	if (ret < 0)
142 		return ret;
143 
144 	ret = add_resource(&kimage_res, &bss_res);
145 
146 	return ret;
147 }
148 
149 static void __init init_resources(void)
150 {
151 	struct memblock_region *region = NULL;
152 	struct resource *res = NULL;
153 	struct resource *mem_res = NULL;
154 	size_t mem_res_sz = 0;
155 	int num_resources = 0, res_idx = 0;
156 	int ret = 0;
157 
158 	/* + 1 as memblock_alloc() might increase memblock.reserved.cnt */
159 	num_resources = memblock.memory.cnt + memblock.reserved.cnt + 1;
160 	res_idx = num_resources - 1;
161 
162 	mem_res_sz = num_resources * sizeof(*mem_res);
163 	mem_res = memblock_alloc(mem_res_sz, SMP_CACHE_BYTES);
164 	if (!mem_res)
165 		panic("%s: Failed to allocate %zu bytes\n", __func__, mem_res_sz);
166 
167 	/*
168 	 * Start by adding the reserved regions, if they overlap
169 	 * with /memory regions, insert_resource later on will take
170 	 * care of it.
171 	 */
172 	ret = add_kernel_resources();
173 	if (ret < 0)
174 		goto error;
175 
176 #ifdef CONFIG_KEXEC_CORE
177 	if (crashk_res.start != crashk_res.end) {
178 		ret = add_resource(&iomem_resource, &crashk_res);
179 		if (ret < 0)
180 			goto error;
181 	}
182 	if (crashk_low_res.start != crashk_low_res.end) {
183 		ret = add_resource(&iomem_resource, &crashk_low_res);
184 		if (ret < 0)
185 			goto error;
186 	}
187 #endif
188 
189 #ifdef CONFIG_CRASH_DUMP
190 	if (elfcorehdr_size > 0) {
191 		elfcorehdr_res.start = elfcorehdr_addr;
192 		elfcorehdr_res.end = elfcorehdr_addr + elfcorehdr_size - 1;
193 		elfcorehdr_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
194 		add_resource(&iomem_resource, &elfcorehdr_res);
195 	}
196 #endif
197 
198 	for_each_reserved_mem_region(region) {
199 		res = &mem_res[res_idx--];
200 
201 		res->name = "Reserved";
202 		res->flags = IORESOURCE_MEM | IORESOURCE_EXCLUSIVE;
203 		res->start = __pfn_to_phys(memblock_region_reserved_base_pfn(region));
204 		res->end = __pfn_to_phys(memblock_region_reserved_end_pfn(region)) - 1;
205 
206 		/*
207 		 * Ignore any other reserved regions within
208 		 * system memory.
209 		 */
210 		if (memblock_is_memory(res->start)) {
211 			/* Re-use this pre-allocated resource */
212 			res_idx++;
213 			continue;
214 		}
215 
216 		ret = add_resource(&iomem_resource, res);
217 		if (ret < 0)
218 			goto error;
219 	}
220 
221 	/* Add /memory regions to the resource tree */
222 	for_each_mem_region(region) {
223 		res = &mem_res[res_idx--];
224 
225 		if (unlikely(memblock_is_nomap(region))) {
226 			res->name = "Reserved";
227 			res->flags = IORESOURCE_MEM | IORESOURCE_EXCLUSIVE;
228 		} else {
229 			res->name = "System RAM";
230 			res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
231 		}
232 
233 		res->start = __pfn_to_phys(memblock_region_memory_base_pfn(region));
234 		res->end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1;
235 
236 		ret = add_resource(&iomem_resource, res);
237 		if (ret < 0)
238 			goto error;
239 	}
240 
241 	/* Clean-up any unused pre-allocated resources */
242 	if (res_idx >= 0)
243 		memblock_free(mem_res, (res_idx + 1) * sizeof(*mem_res));
244 	return;
245 
246  error:
247 	/* Better an empty resource tree than an inconsistent one */
248 	release_child_resources(&iomem_resource);
249 	memblock_free(mem_res, mem_res_sz);
250 }
251 
252 
253 static void __init parse_dtb(void)
254 {
255 	/* Early scan of device tree from init memory */
256 	if (early_init_dt_scan(dtb_early_va)) {
257 		const char *name = of_flat_dt_get_machine_name();
258 
259 		if (name) {
260 			pr_info("Machine model: %s\n", name);
261 			dump_stack_set_arch_desc("%s (DT)", name);
262 		}
263 	} else {
264 		pr_err("No DTB passed to the kernel\n");
265 	}
266 
267 #ifdef CONFIG_CMDLINE_FORCE
268 	strscpy(boot_command_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
269 	pr_info("Forcing kernel command line to: %s\n", boot_command_line);
270 #endif
271 }
272 
273 extern void __init init_rt_signal_env(void);
274 
275 void __init setup_arch(char **cmdline_p)
276 {
277 	parse_dtb();
278 	setup_initial_init_mm(_stext, _etext, _edata, _end);
279 
280 	*cmdline_p = boot_command_line;
281 
282 	early_ioremap_setup();
283 	sbi_init();
284 	jump_label_init();
285 	parse_early_param();
286 
287 	efi_init();
288 	paging_init();
289 
290 	/* Parse the ACPI tables for possible boot-time configuration */
291 	acpi_boot_table_init();
292 
293 #if IS_ENABLED(CONFIG_BUILTIN_DTB)
294 	unflatten_and_copy_device_tree();
295 #else
296 	unflatten_device_tree();
297 #endif
298 	misc_mem_init();
299 
300 	init_resources();
301 
302 #ifdef CONFIG_KASAN
303 	kasan_init();
304 #endif
305 
306 #ifdef CONFIG_SMP
307 	setup_smp();
308 #endif
309 
310 	if (!acpi_disabled)
311 		acpi_init_rintc_map();
312 
313 	riscv_init_cbo_blocksizes();
314 	riscv_fill_hwcap();
315 	init_rt_signal_env();
316 	apply_boot_alternatives();
317 	if (IS_ENABLED(CONFIG_RISCV_ISA_ZICBOM) &&
318 	    riscv_isa_extension_available(NULL, ZICBOM))
319 		riscv_noncoherent_supported();
320 	riscv_set_dma_cache_alignment();
321 }
322 
323 static int __init topology_init(void)
324 {
325 	int i, ret;
326 
327 	for_each_possible_cpu(i) {
328 		struct cpu *cpu = &per_cpu(cpu_devices, i);
329 
330 		cpu->hotpluggable = cpu_has_hotplug(i);
331 		ret = register_cpu(cpu, i);
332 		if (unlikely(ret))
333 			pr_warn("Warning: %s: register_cpu %d failed (%d)\n",
334 			       __func__, i, ret);
335 	}
336 
337 	return 0;
338 }
339 subsys_initcall(topology_init);
340 
341 void free_initmem(void)
342 {
343 	if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)) {
344 		set_kernel_memory(lm_alias(__init_begin), lm_alias(__init_end), set_memory_rw_nx);
345 		if (IS_ENABLED(CONFIG_64BIT))
346 			set_kernel_memory(__init_begin, __init_end, set_memory_nx);
347 	}
348 
349 	free_initmem_default(POISON_FREE_INITMEM);
350 }
351 
352 static int dump_kernel_offset(struct notifier_block *self,
353 			      unsigned long v, void *p)
354 {
355 	pr_emerg("Kernel Offset: 0x%lx from 0x%lx\n",
356 		 kernel_map.virt_offset,
357 		 KERNEL_LINK_ADDR);
358 
359 	return 0;
360 }
361 
362 static struct notifier_block kernel_offset_notifier = {
363 	.notifier_call = dump_kernel_offset
364 };
365 
366 static int __init register_kernel_offset_dumper(void)
367 {
368 	if (IS_ENABLED(CONFIG_RANDOMIZE_BASE))
369 		atomic_notifier_chain_register(&panic_notifier_list,
370 					       &kernel_offset_notifier);
371 
372 	return 0;
373 }
374 device_initcall(register_kernel_offset_dumper);
375