xref: /linux/arch/arm64/kernel/setup.c (revision 4413e16d9d21673bb5048a2e542f1aaa00015c2e)
1 /*
2  * Based on arch/arm/kernel/setup.c
3  *
4  * Copyright (C) 1995-2001 Russell King
5  * Copyright (C) 2012 ARM Ltd.
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
18  */
19 
20 #include <linux/export.h>
21 #include <linux/kernel.h>
22 #include <linux/stddef.h>
23 #include <linux/ioport.h>
24 #include <linux/delay.h>
25 #include <linux/utsname.h>
26 #include <linux/initrd.h>
27 #include <linux/console.h>
28 #include <linux/bootmem.h>
29 #include <linux/seq_file.h>
30 #include <linux/screen_info.h>
31 #include <linux/init.h>
32 #include <linux/kexec.h>
33 #include <linux/crash_dump.h>
34 #include <linux/root_dev.h>
35 #include <linux/cpu.h>
36 #include <linux/interrupt.h>
37 #include <linux/smp.h>
38 #include <linux/fs.h>
39 #include <linux/proc_fs.h>
40 #include <linux/memblock.h>
41 #include <linux/of_fdt.h>
42 
43 #include <asm/cputype.h>
44 #include <asm/elf.h>
45 #include <asm/cputable.h>
46 #include <asm/sections.h>
47 #include <asm/setup.h>
48 #include <asm/cacheflush.h>
49 #include <asm/tlbflush.h>
50 #include <asm/traps.h>
51 #include <asm/memblock.h>
52 
53 unsigned int processor_id;
54 EXPORT_SYMBOL(processor_id);
55 
56 unsigned int elf_hwcap __read_mostly;
57 EXPORT_SYMBOL_GPL(elf_hwcap);
58 
59 static const char *cpu_name;
60 static const char *machine_name;
61 phys_addr_t __fdt_pointer __initdata;
62 
63 /*
64  * Standard memory resources
65  */
66 static struct resource mem_res[] = {
67 	{
68 		.name = "Kernel code",
69 		.start = 0,
70 		.end = 0,
71 		.flags = IORESOURCE_MEM
72 	},
73 	{
74 		.name = "Kernel data",
75 		.start = 0,
76 		.end = 0,
77 		.flags = IORESOURCE_MEM
78 	}
79 };
80 
81 #define kernel_code mem_res[0]
82 #define kernel_data mem_res[1]
83 
84 void __init early_print(const char *str, ...)
85 {
86 	char buf[256];
87 	va_list ap;
88 
89 	va_start(ap, str);
90 	vsnprintf(buf, sizeof(buf), str, ap);
91 	va_end(ap);
92 
93 	printk("%s", buf);
94 }
95 
96 static void __init setup_processor(void)
97 {
98 	struct cpu_info *cpu_info;
99 
100 	/*
101 	 * locate processor in the list of supported processor
102 	 * types.  The linker builds this table for us from the
103 	 * entries in arch/arm/mm/proc.S
104 	 */
105 	cpu_info = lookup_processor_type(read_cpuid_id());
106 	if (!cpu_info) {
107 		printk("CPU configuration botched (ID %08x), unable to continue.\n",
108 		       read_cpuid_id());
109 		while (1);
110 	}
111 
112 	cpu_name = cpu_info->cpu_name;
113 
114 	printk("CPU: %s [%08x] revision %d\n",
115 	       cpu_name, read_cpuid_id(), read_cpuid_id() & 15);
116 
117 	sprintf(init_utsname()->machine, "aarch64");
118 	elf_hwcap = 0;
119 }
120 
121 static void __init setup_machine_fdt(phys_addr_t dt_phys)
122 {
123 	struct boot_param_header *devtree;
124 	unsigned long dt_root;
125 
126 	/* Check we have a non-NULL DT pointer */
127 	if (!dt_phys) {
128 		early_print("\n"
129 			"Error: NULL or invalid device tree blob\n"
130 			"The dtb must be 8-byte aligned and passed in the first 512MB of memory\n"
131 			"\nPlease check your bootloader.\n");
132 
133 		while (true)
134 			cpu_relax();
135 
136 	}
137 
138 	devtree = phys_to_virt(dt_phys);
139 
140 	/* Check device tree validity */
141 	if (be32_to_cpu(devtree->magic) != OF_DT_HEADER) {
142 		early_print("\n"
143 			"Error: invalid device tree blob at physical address 0x%p (virtual address 0x%p)\n"
144 			"Expected 0x%x, found 0x%x\n"
145 			"\nPlease check your bootloader.\n",
146 			dt_phys, devtree, OF_DT_HEADER,
147 			be32_to_cpu(devtree->magic));
148 
149 		while (true)
150 			cpu_relax();
151 	}
152 
153 	initial_boot_params = devtree;
154 	dt_root = of_get_flat_dt_root();
155 
156 	machine_name = of_get_flat_dt_prop(dt_root, "model", NULL);
157 	if (!machine_name)
158 		machine_name = of_get_flat_dt_prop(dt_root, "compatible", NULL);
159 	if (!machine_name)
160 		machine_name = "<unknown>";
161 	pr_info("Machine: %s\n", machine_name);
162 
163 	/* Retrieve various information from the /chosen node */
164 	of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line);
165 	/* Initialize {size,address}-cells info */
166 	of_scan_flat_dt(early_init_dt_scan_root, NULL);
167 	/* Setup memory, calling early_init_dt_add_memory_arch */
168 	of_scan_flat_dt(early_init_dt_scan_memory, NULL);
169 }
170 
171 void __init early_init_dt_add_memory_arch(u64 base, u64 size)
172 {
173 	size &= PAGE_MASK;
174 	memblock_add(base, size);
175 }
176 
177 void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
178 {
179 	return __va(memblock_alloc(size, align));
180 }
181 
182 /*
183  * Limit the memory size that was specified via FDT.
184  */
185 static int __init early_mem(char *p)
186 {
187 	phys_addr_t limit;
188 
189 	if (!p)
190 		return 1;
191 
192 	limit = memparse(p, &p) & PAGE_MASK;
193 	pr_notice("Memory limited to %lldMB\n", limit >> 20);
194 
195 	memblock_enforce_memory_limit(limit);
196 
197 	return 0;
198 }
199 early_param("mem", early_mem);
200 
201 static void __init request_standard_resources(void)
202 {
203 	struct memblock_region *region;
204 	struct resource *res;
205 
206 	kernel_code.start   = virt_to_phys(_text);
207 	kernel_code.end     = virt_to_phys(_etext - 1);
208 	kernel_data.start   = virt_to_phys(_sdata);
209 	kernel_data.end     = virt_to_phys(_end - 1);
210 
211 	for_each_memblock(memory, region) {
212 		res = alloc_bootmem_low(sizeof(*res));
213 		res->name  = "System RAM";
214 		res->start = __pfn_to_phys(memblock_region_memory_base_pfn(region));
215 		res->end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1;
216 		res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
217 
218 		request_resource(&iomem_resource, res);
219 
220 		if (kernel_code.start >= res->start &&
221 		    kernel_code.end <= res->end)
222 			request_resource(res, &kernel_code);
223 		if (kernel_data.start >= res->start &&
224 		    kernel_data.end <= res->end)
225 			request_resource(res, &kernel_data);
226 	}
227 }
228 
229 void __init setup_arch(char **cmdline_p)
230 {
231 	setup_processor();
232 
233 	setup_machine_fdt(__fdt_pointer);
234 
235 	init_mm.start_code = (unsigned long) _text;
236 	init_mm.end_code   = (unsigned long) _etext;
237 	init_mm.end_data   = (unsigned long) _edata;
238 	init_mm.brk	   = (unsigned long) _end;
239 
240 	*cmdline_p = boot_command_line;
241 
242 	parse_early_param();
243 
244 	arm64_memblock_init();
245 
246 	paging_init();
247 	request_standard_resources();
248 
249 	unflatten_device_tree();
250 
251 #ifdef CONFIG_SMP
252 	smp_init_cpus();
253 #endif
254 
255 #ifdef CONFIG_VT
256 #if defined(CONFIG_VGA_CONSOLE)
257 	conswitchp = &vga_con;
258 #elif defined(CONFIG_DUMMY_CONSOLE)
259 	conswitchp = &dummy_con;
260 #endif
261 #endif
262 }
263 
264 static DEFINE_PER_CPU(struct cpu, cpu_data);
265 
266 static int __init topology_init(void)
267 {
268 	int i;
269 
270 	for_each_possible_cpu(i) {
271 		struct cpu *cpu = &per_cpu(cpu_data, i);
272 		cpu->hotpluggable = 1;
273 		register_cpu(cpu, i);
274 	}
275 
276 	return 0;
277 }
278 subsys_initcall(topology_init);
279 
280 static const char *hwcap_str[] = {
281 	"fp",
282 	"asimd",
283 	NULL
284 };
285 
286 static int c_show(struct seq_file *m, void *v)
287 {
288 	int i;
289 
290 	seq_printf(m, "Processor\t: %s rev %d (%s)\n",
291 		   cpu_name, read_cpuid_id() & 15, ELF_PLATFORM);
292 
293 	for_each_online_cpu(i) {
294 		/*
295 		 * glibc reads /proc/cpuinfo to determine the number of
296 		 * online processors, looking for lines beginning with
297 		 * "processor".  Give glibc what it expects.
298 		 */
299 #ifdef CONFIG_SMP
300 		seq_printf(m, "processor\t: %d\n", i);
301 #endif
302 		seq_printf(m, "BogoMIPS\t: %lu.%02lu\n\n",
303 			   loops_per_jiffy / (500000UL/HZ),
304 			   loops_per_jiffy / (5000UL/HZ) % 100);
305 	}
306 
307 	/* dump out the processor features */
308 	seq_puts(m, "Features\t: ");
309 
310 	for (i = 0; hwcap_str[i]; i++)
311 		if (elf_hwcap & (1 << i))
312 			seq_printf(m, "%s ", hwcap_str[i]);
313 
314 	seq_printf(m, "\nCPU implementer\t: 0x%02x\n", read_cpuid_id() >> 24);
315 	seq_printf(m, "CPU architecture: AArch64\n");
316 	seq_printf(m, "CPU variant\t: 0x%x\n", (read_cpuid_id() >> 20) & 15);
317 	seq_printf(m, "CPU part\t: 0x%03x\n", (read_cpuid_id() >> 4) & 0xfff);
318 	seq_printf(m, "CPU revision\t: %d\n", read_cpuid_id() & 15);
319 
320 	seq_puts(m, "\n");
321 
322 	seq_printf(m, "Hardware\t: %s\n", machine_name);
323 
324 	return 0;
325 }
326 
327 static void *c_start(struct seq_file *m, loff_t *pos)
328 {
329 	return *pos < 1 ? (void *)1 : NULL;
330 }
331 
332 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
333 {
334 	++*pos;
335 	return NULL;
336 }
337 
338 static void c_stop(struct seq_file *m, void *v)
339 {
340 }
341 
342 const struct seq_operations cpuinfo_op = {
343 	.start	= c_start,
344 	.next	= c_next,
345 	.stop	= c_stop,
346 	.show	= c_show
347 };
348