xref: /openbmc/linux/arch/arm64/kernel/setup.c (revision 8fdff1dc)
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 	base &= PAGE_MASK;
174 	size &= PAGE_MASK;
175 	if (base + size < PHYS_OFFSET) {
176 		pr_warning("Ignoring memory block 0x%llx - 0x%llx\n",
177 			   base, base + size);
178 		return;
179 	}
180 	if (base < PHYS_OFFSET) {
181 		pr_warning("Ignoring memory range 0x%llx - 0x%llx\n",
182 			   base, PHYS_OFFSET);
183 		size -= PHYS_OFFSET - base;
184 		base = PHYS_OFFSET;
185 	}
186 	memblock_add(base, size);
187 }
188 
189 void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
190 {
191 	return __va(memblock_alloc(size, align));
192 }
193 
194 /*
195  * Limit the memory size that was specified via FDT.
196  */
197 static int __init early_mem(char *p)
198 {
199 	phys_addr_t limit;
200 
201 	if (!p)
202 		return 1;
203 
204 	limit = memparse(p, &p) & PAGE_MASK;
205 	pr_notice("Memory limited to %lldMB\n", limit >> 20);
206 
207 	memblock_enforce_memory_limit(limit);
208 
209 	return 0;
210 }
211 early_param("mem", early_mem);
212 
213 static void __init request_standard_resources(void)
214 {
215 	struct memblock_region *region;
216 	struct resource *res;
217 
218 	kernel_code.start   = virt_to_phys(_text);
219 	kernel_code.end     = virt_to_phys(_etext - 1);
220 	kernel_data.start   = virt_to_phys(_sdata);
221 	kernel_data.end     = virt_to_phys(_end - 1);
222 
223 	for_each_memblock(memory, region) {
224 		res = alloc_bootmem_low(sizeof(*res));
225 		res->name  = "System RAM";
226 		res->start = __pfn_to_phys(memblock_region_memory_base_pfn(region));
227 		res->end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1;
228 		res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
229 
230 		request_resource(&iomem_resource, res);
231 
232 		if (kernel_code.start >= res->start &&
233 		    kernel_code.end <= res->end)
234 			request_resource(res, &kernel_code);
235 		if (kernel_data.start >= res->start &&
236 		    kernel_data.end <= res->end)
237 			request_resource(res, &kernel_data);
238 	}
239 }
240 
241 void __init setup_arch(char **cmdline_p)
242 {
243 	setup_processor();
244 
245 	setup_machine_fdt(__fdt_pointer);
246 
247 	init_mm.start_code = (unsigned long) _text;
248 	init_mm.end_code   = (unsigned long) _etext;
249 	init_mm.end_data   = (unsigned long) _edata;
250 	init_mm.brk	   = (unsigned long) _end;
251 
252 	*cmdline_p = boot_command_line;
253 
254 	parse_early_param();
255 
256 	arm64_memblock_init();
257 
258 	paging_init();
259 	request_standard_resources();
260 
261 	unflatten_device_tree();
262 
263 #ifdef CONFIG_SMP
264 	smp_init_cpus();
265 #endif
266 
267 #ifdef CONFIG_VT
268 #if defined(CONFIG_VGA_CONSOLE)
269 	conswitchp = &vga_con;
270 #elif defined(CONFIG_DUMMY_CONSOLE)
271 	conswitchp = &dummy_con;
272 #endif
273 #endif
274 }
275 
276 static DEFINE_PER_CPU(struct cpu, cpu_data);
277 
278 static int __init topology_init(void)
279 {
280 	int i;
281 
282 	for_each_possible_cpu(i) {
283 		struct cpu *cpu = &per_cpu(cpu_data, i);
284 		cpu->hotpluggable = 1;
285 		register_cpu(cpu, i);
286 	}
287 
288 	return 0;
289 }
290 subsys_initcall(topology_init);
291 
292 static const char *hwcap_str[] = {
293 	"fp",
294 	"asimd",
295 	NULL
296 };
297 
298 static int c_show(struct seq_file *m, void *v)
299 {
300 	int i;
301 
302 	seq_printf(m, "Processor\t: %s rev %d (%s)\n",
303 		   cpu_name, read_cpuid_id() & 15, ELF_PLATFORM);
304 
305 	for_each_online_cpu(i) {
306 		/*
307 		 * glibc reads /proc/cpuinfo to determine the number of
308 		 * online processors, looking for lines beginning with
309 		 * "processor".  Give glibc what it expects.
310 		 */
311 #ifdef CONFIG_SMP
312 		seq_printf(m, "processor\t: %d\n", i);
313 #endif
314 		seq_printf(m, "BogoMIPS\t: %lu.%02lu\n\n",
315 			   loops_per_jiffy / (500000UL/HZ),
316 			   loops_per_jiffy / (5000UL/HZ) % 100);
317 	}
318 
319 	/* dump out the processor features */
320 	seq_puts(m, "Features\t: ");
321 
322 	for (i = 0; hwcap_str[i]; i++)
323 		if (elf_hwcap & (1 << i))
324 			seq_printf(m, "%s ", hwcap_str[i]);
325 
326 	seq_printf(m, "\nCPU implementer\t: 0x%02x\n", read_cpuid_id() >> 24);
327 	seq_printf(m, "CPU architecture: AArch64\n");
328 	seq_printf(m, "CPU variant\t: 0x%x\n", (read_cpuid_id() >> 20) & 15);
329 	seq_printf(m, "CPU part\t: 0x%03x\n", (read_cpuid_id() >> 4) & 0xfff);
330 	seq_printf(m, "CPU revision\t: %d\n", read_cpuid_id() & 15);
331 
332 	seq_puts(m, "\n");
333 
334 	seq_printf(m, "Hardware\t: %s\n", machine_name);
335 
336 	return 0;
337 }
338 
339 static void *c_start(struct seq_file *m, loff_t *pos)
340 {
341 	return *pos < 1 ? (void *)1 : NULL;
342 }
343 
344 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
345 {
346 	++*pos;
347 	return NULL;
348 }
349 
350 static void c_stop(struct seq_file *m, void *v)
351 {
352 }
353 
354 const struct seq_operations cpuinfo_op = {
355 	.start	= c_start,
356 	.next	= c_next,
357 	.stop	= c_stop,
358 	.show	= c_show
359 };
360