setup.c

  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 */
 49atomic_t hart_lottery __section(".sdata")
 50#ifdef CONFIG_XIP_KERNEL
 51= ATOMIC_INIT(0xC001BEEF)
 52#endif
 53;
 54unsigned long boot_cpu_hartid;
 55EXPORT_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 */
 63static struct resource kimage_res = { .name = "Kernel image", };
 64static struct resource code_res = { .name = "Kernel code", };
 65static struct resource data_res = { .name = "Kernel data", };
 66static struct resource rodata_res = { .name = "Kernel rodata", };
 67static struct resource bss_res = { .name = "Kernel bss", };
 68#ifdef CONFIG_CRASH_DUMP
 69static struct resource elfcorehdr_res = { .name = "ELF Core hdr", };
 70#endif
 71
 72static int num_standard_resources;
 73static struct resource *standard_resources;
 74
 75static 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
 90static 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
142static 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
234static 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}
260arch_initcall(reserve_memblock_reserved_regions);
261
262static 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)
278DEFINE_STATIC_KEY_TRUE(qspinlock_key);
279EXPORT_SYMBOL(qspinlock_key);
280#endif
281
282static 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	    IS_ENABLED(CONFIG_TOOLCHAIN_HAS_ZACAS) &&
294	    riscv_isa_extension_available(NULL, ZABHA) &&
295	    riscv_isa_extension_available(NULL, ZACAS)) {
296		using_ext = "using Zabha";
297	} else if (riscv_isa_extension_available(NULL, ZICCRSE)) {
298		using_ext = "using Ziccrse";
299	}
300#if defined(CONFIG_RISCV_COMBO_SPINLOCKS)
301	else {
302		static_branch_disable(&qspinlock_key);
303		pr_info("Ticket spinlock: enabled\n");
304		return;
305	}
306#endif
307
308	if (!using_ext)
309		pr_err("Queued spinlock without Zabha or Ziccrse");
310	else
311		pr_info("Queued spinlock %s: enabled\n", using_ext);
312}
313
314extern void __init init_rt_signal_env(void);
315
316void __init setup_arch(char **cmdline_p)
317{
318	parse_dtb();
319	setup_initial_init_mm(_stext, _etext, _edata, _end);
320
321	*cmdline_p = boot_command_line;
322
323	early_ioremap_setup();
324	sbi_init();
325	jump_label_init();
326	parse_early_param();
327
328	efi_init();
329	paging_init();
330
331	/* Parse the ACPI tables for possible boot-time configuration */
332	acpi_boot_table_init();
333
334	if (acpi_disabled) {
335#if IS_ENABLED(CONFIG_BUILTIN_DTB)
336		unflatten_and_copy_device_tree();
337#else
338		unflatten_device_tree();
339#endif
340	}
341
342	misc_mem_init();
343
344	init_resources();
345
346#ifdef CONFIG_KASAN
347	kasan_init();
348#endif
349
350#ifdef CONFIG_SMP
351	setup_smp();
352#endif
353
354	if (!acpi_disabled) {
355		acpi_init_rintc_map();
356		acpi_map_cpus_to_nodes();
357	}
358
359	riscv_init_cbo_blocksizes();
360	riscv_fill_hwcap();
361	apply_boot_alternatives();
362	init_rt_signal_env();
363
364	if (IS_ENABLED(CONFIG_RISCV_ISA_ZICBOM) &&
365	    riscv_isa_extension_available(NULL, ZICBOM))
366		riscv_noncoherent_supported();
367	riscv_set_dma_cache_alignment();
368
369	riscv_user_isa_enable();
370	riscv_spinlock_init();
371
372	if (!IS_ENABLED(CONFIG_RISCV_ISA_ZBB) || !riscv_isa_extension_available(NULL, ZBB))
373		static_branch_disable(&efficient_ffs_key);
374}
375
376bool arch_cpu_is_hotpluggable(int cpu)
377{
378	return cpu_has_hotplug(cpu);
379}
380
381void free_initmem(void)
382{
383	if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)) {
384		set_kernel_memory(lm_alias(__init_begin), lm_alias(__init_end), set_memory_rw_nx);
385		if (IS_ENABLED(CONFIG_64BIT))
386			set_kernel_memory(__init_begin, __init_end, set_memory_nx);
387	}
388
389	free_initmem_default(POISON_FREE_INITMEM);
390}
391
392static int dump_kernel_offset(struct notifier_block *self,
393			      unsigned long v, void *p)
394{
395	pr_emerg("Kernel Offset: 0x%lx from 0x%lx\n",
396		 kernel_map.virt_offset,
397		 KERNEL_LINK_ADDR);
398
399	return 0;
400}
401
402static struct notifier_block kernel_offset_notifier = {
403	.notifier_call = dump_kernel_offset
404};
405
406static int __init register_kernel_offset_dumper(void)
407{
408	if (IS_ENABLED(CONFIG_RANDOMIZE_BASE))
409		atomic_notifier_chain_register(&panic_notifier_list,
410					       &kernel_offset_notifier);
411
412	return 0;
413}
414device_initcall(register_kernel_offset_dumper);