xref: /openbmc/linux/arch/arm64/kernel/setup.c (revision 9d749629)
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 #include <linux/of_platform.h>
43 
44 #include <asm/cputype.h>
45 #include <asm/elf.h>
46 #include <asm/cputable.h>
47 #include <asm/sections.h>
48 #include <asm/setup.h>
49 #include <asm/cacheflush.h>
50 #include <asm/tlbflush.h>
51 #include <asm/traps.h>
52 #include <asm/memblock.h>
53 #include <asm/psci.h>
54 
55 unsigned int processor_id;
56 EXPORT_SYMBOL(processor_id);
57 
58 unsigned int elf_hwcap __read_mostly;
59 EXPORT_SYMBOL_GPL(elf_hwcap);
60 
61 static const char *cpu_name;
62 static const char *machine_name;
63 phys_addr_t __fdt_pointer __initdata;
64 
65 /*
66  * Standard memory resources
67  */
68 static struct resource mem_res[] = {
69 	{
70 		.name = "Kernel code",
71 		.start = 0,
72 		.end = 0,
73 		.flags = IORESOURCE_MEM
74 	},
75 	{
76 		.name = "Kernel data",
77 		.start = 0,
78 		.end = 0,
79 		.flags = IORESOURCE_MEM
80 	}
81 };
82 
83 #define kernel_code mem_res[0]
84 #define kernel_data mem_res[1]
85 
86 void __init early_print(const char *str, ...)
87 {
88 	char buf[256];
89 	va_list ap;
90 
91 	va_start(ap, str);
92 	vsnprintf(buf, sizeof(buf), str, ap);
93 	va_end(ap);
94 
95 	printk("%s", buf);
96 }
97 
98 static void __init setup_processor(void)
99 {
100 	struct cpu_info *cpu_info;
101 
102 	/*
103 	 * locate processor in the list of supported processor
104 	 * types.  The linker builds this table for us from the
105 	 * entries in arch/arm/mm/proc.S
106 	 */
107 	cpu_info = lookup_processor_type(read_cpuid_id());
108 	if (!cpu_info) {
109 		printk("CPU configuration botched (ID %08x), unable to continue.\n",
110 		       read_cpuid_id());
111 		while (1);
112 	}
113 
114 	cpu_name = cpu_info->cpu_name;
115 
116 	printk("CPU: %s [%08x] revision %d\n",
117 	       cpu_name, read_cpuid_id(), read_cpuid_id() & 15);
118 
119 	sprintf(init_utsname()->machine, "aarch64");
120 	elf_hwcap = 0;
121 }
122 
123 static void __init setup_machine_fdt(phys_addr_t dt_phys)
124 {
125 	struct boot_param_header *devtree;
126 	unsigned long dt_root;
127 
128 	/* Check we have a non-NULL DT pointer */
129 	if (!dt_phys) {
130 		early_print("\n"
131 			"Error: NULL or invalid device tree blob\n"
132 			"The dtb must be 8-byte aligned and passed in the first 512MB of memory\n"
133 			"\nPlease check your bootloader.\n");
134 
135 		while (true)
136 			cpu_relax();
137 
138 	}
139 
140 	devtree = phys_to_virt(dt_phys);
141 
142 	/* Check device tree validity */
143 	if (be32_to_cpu(devtree->magic) != OF_DT_HEADER) {
144 		early_print("\n"
145 			"Error: invalid device tree blob at physical address 0x%p (virtual address 0x%p)\n"
146 			"Expected 0x%x, found 0x%x\n"
147 			"\nPlease check your bootloader.\n",
148 			dt_phys, devtree, OF_DT_HEADER,
149 			be32_to_cpu(devtree->magic));
150 
151 		while (true)
152 			cpu_relax();
153 	}
154 
155 	initial_boot_params = devtree;
156 	dt_root = of_get_flat_dt_root();
157 
158 	machine_name = of_get_flat_dt_prop(dt_root, "model", NULL);
159 	if (!machine_name)
160 		machine_name = of_get_flat_dt_prop(dt_root, "compatible", NULL);
161 	if (!machine_name)
162 		machine_name = "<unknown>";
163 	pr_info("Machine: %s\n", machine_name);
164 
165 	/* Retrieve various information from the /chosen node */
166 	of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line);
167 	/* Initialize {size,address}-cells info */
168 	of_scan_flat_dt(early_init_dt_scan_root, NULL);
169 	/* Setup memory, calling early_init_dt_add_memory_arch */
170 	of_scan_flat_dt(early_init_dt_scan_memory, NULL);
171 }
172 
173 void __init early_init_dt_add_memory_arch(u64 base, u64 size)
174 {
175 	base &= PAGE_MASK;
176 	size &= PAGE_MASK;
177 	if (base + size < PHYS_OFFSET) {
178 		pr_warning("Ignoring memory block 0x%llx - 0x%llx\n",
179 			   base, base + size);
180 		return;
181 	}
182 	if (base < PHYS_OFFSET) {
183 		pr_warning("Ignoring memory range 0x%llx - 0x%llx\n",
184 			   base, PHYS_OFFSET);
185 		size -= PHYS_OFFSET - base;
186 		base = PHYS_OFFSET;
187 	}
188 	memblock_add(base, size);
189 }
190 
191 void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
192 {
193 	return __va(memblock_alloc(size, align));
194 }
195 
196 /*
197  * Limit the memory size that was specified via FDT.
198  */
199 static int __init early_mem(char *p)
200 {
201 	phys_addr_t limit;
202 
203 	if (!p)
204 		return 1;
205 
206 	limit = memparse(p, &p) & PAGE_MASK;
207 	pr_notice("Memory limited to %lldMB\n", limit >> 20);
208 
209 	memblock_enforce_memory_limit(limit);
210 
211 	return 0;
212 }
213 early_param("mem", early_mem);
214 
215 static void __init request_standard_resources(void)
216 {
217 	struct memblock_region *region;
218 	struct resource *res;
219 
220 	kernel_code.start   = virt_to_phys(_text);
221 	kernel_code.end     = virt_to_phys(_etext - 1);
222 	kernel_data.start   = virt_to_phys(_sdata);
223 	kernel_data.end     = virt_to_phys(_end - 1);
224 
225 	for_each_memblock(memory, region) {
226 		res = alloc_bootmem_low(sizeof(*res));
227 		res->name  = "System RAM";
228 		res->start = __pfn_to_phys(memblock_region_memory_base_pfn(region));
229 		res->end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1;
230 		res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
231 
232 		request_resource(&iomem_resource, res);
233 
234 		if (kernel_code.start >= res->start &&
235 		    kernel_code.end <= res->end)
236 			request_resource(res, &kernel_code);
237 		if (kernel_data.start >= res->start &&
238 		    kernel_data.end <= res->end)
239 			request_resource(res, &kernel_data);
240 	}
241 }
242 
243 void __init setup_arch(char **cmdline_p)
244 {
245 	setup_processor();
246 
247 	setup_machine_fdt(__fdt_pointer);
248 
249 	init_mm.start_code = (unsigned long) _text;
250 	init_mm.end_code   = (unsigned long) _etext;
251 	init_mm.end_data   = (unsigned long) _edata;
252 	init_mm.brk	   = (unsigned long) _end;
253 
254 	*cmdline_p = boot_command_line;
255 
256 	parse_early_param();
257 
258 	arm64_memblock_init();
259 
260 	paging_init();
261 	request_standard_resources();
262 
263 	unflatten_device_tree();
264 
265 	psci_init();
266 
267 #ifdef CONFIG_SMP
268 	smp_init_cpus();
269 #endif
270 
271 #ifdef CONFIG_VT
272 #if defined(CONFIG_VGA_CONSOLE)
273 	conswitchp = &vga_con;
274 #elif defined(CONFIG_DUMMY_CONSOLE)
275 	conswitchp = &dummy_con;
276 #endif
277 #endif
278 }
279 
280 static DEFINE_PER_CPU(struct cpu, cpu_data);
281 
282 static int __init topology_init(void)
283 {
284 	int i;
285 
286 	for_each_possible_cpu(i) {
287 		struct cpu *cpu = &per_cpu(cpu_data, i);
288 		cpu->hotpluggable = 1;
289 		register_cpu(cpu, i);
290 	}
291 
292 	return 0;
293 }
294 subsys_initcall(topology_init);
295 
296 static int __init arm64_device_probe(void)
297 {
298 	of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
299 	return 0;
300 }
301 device_initcall(arm64_device_probe);
302 
303 static const char *hwcap_str[] = {
304 	"fp",
305 	"asimd",
306 	NULL
307 };
308 
309 static int c_show(struct seq_file *m, void *v)
310 {
311 	int i;
312 
313 	seq_printf(m, "Processor\t: %s rev %d (%s)\n",
314 		   cpu_name, read_cpuid_id() & 15, ELF_PLATFORM);
315 
316 	for_each_online_cpu(i) {
317 		/*
318 		 * glibc reads /proc/cpuinfo to determine the number of
319 		 * online processors, looking for lines beginning with
320 		 * "processor".  Give glibc what it expects.
321 		 */
322 #ifdef CONFIG_SMP
323 		seq_printf(m, "processor\t: %d\n", i);
324 #endif
325 		seq_printf(m, "BogoMIPS\t: %lu.%02lu\n\n",
326 			   loops_per_jiffy / (500000UL/HZ),
327 			   loops_per_jiffy / (5000UL/HZ) % 100);
328 	}
329 
330 	/* dump out the processor features */
331 	seq_puts(m, "Features\t: ");
332 
333 	for (i = 0; hwcap_str[i]; i++)
334 		if (elf_hwcap & (1 << i))
335 			seq_printf(m, "%s ", hwcap_str[i]);
336 
337 	seq_printf(m, "\nCPU implementer\t: 0x%02x\n", read_cpuid_id() >> 24);
338 	seq_printf(m, "CPU architecture: AArch64\n");
339 	seq_printf(m, "CPU variant\t: 0x%x\n", (read_cpuid_id() >> 20) & 15);
340 	seq_printf(m, "CPU part\t: 0x%03x\n", (read_cpuid_id() >> 4) & 0xfff);
341 	seq_printf(m, "CPU revision\t: %d\n", read_cpuid_id() & 15);
342 
343 	seq_puts(m, "\n");
344 
345 	seq_printf(m, "Hardware\t: %s\n", machine_name);
346 
347 	return 0;
348 }
349 
350 static void *c_start(struct seq_file *m, loff_t *pos)
351 {
352 	return *pos < 1 ? (void *)1 : NULL;
353 }
354 
355 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
356 {
357 	++*pos;
358 	return NULL;
359 }
360 
361 static void c_stop(struct seq_file *m, void *v)
362 {
363 }
364 
365 const struct seq_operations cpuinfo_op = {
366 	.start	= c_start,
367 	.next	= c_next,
368 	.stop	= c_stop,
369 	.show	= c_show
370 };
371