xref: /openbmc/linux/arch/arm64/kernel/setup.c (revision cdfce539)
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/clk-provider.h>
36 #include <linux/cpu.h>
37 #include <linux/interrupt.h>
38 #include <linux/smp.h>
39 #include <linux/fs.h>
40 #include <linux/proc_fs.h>
41 #include <linux/memblock.h>
42 #include <linux/of_fdt.h>
43 #include <linux/of_platform.h>
44 
45 #include <asm/cputype.h>
46 #include <asm/elf.h>
47 #include <asm/cputable.h>
48 #include <asm/sections.h>
49 #include <asm/setup.h>
50 #include <asm/smp_plat.h>
51 #include <asm/cacheflush.h>
52 #include <asm/tlbflush.h>
53 #include <asm/traps.h>
54 #include <asm/memblock.h>
55 #include <asm/psci.h>
56 
57 unsigned int processor_id;
58 EXPORT_SYMBOL(processor_id);
59 
60 unsigned int elf_hwcap __read_mostly;
61 EXPORT_SYMBOL_GPL(elf_hwcap);
62 
63 static const char *cpu_name;
64 static const char *machine_name;
65 phys_addr_t __fdt_pointer __initdata;
66 
67 /*
68  * Standard memory resources
69  */
70 static struct resource mem_res[] = {
71 	{
72 		.name = "Kernel code",
73 		.start = 0,
74 		.end = 0,
75 		.flags = IORESOURCE_MEM
76 	},
77 	{
78 		.name = "Kernel data",
79 		.start = 0,
80 		.end = 0,
81 		.flags = IORESOURCE_MEM
82 	}
83 };
84 
85 #define kernel_code mem_res[0]
86 #define kernel_data mem_res[1]
87 
88 void __init early_print(const char *str, ...)
89 {
90 	char buf[256];
91 	va_list ap;
92 
93 	va_start(ap, str);
94 	vsnprintf(buf, sizeof(buf), str, ap);
95 	va_end(ap);
96 
97 	printk("%s", buf);
98 }
99 
100 static void __init setup_processor(void)
101 {
102 	struct cpu_info *cpu_info;
103 
104 	/*
105 	 * locate processor in the list of supported processor
106 	 * types.  The linker builds this table for us from the
107 	 * entries in arch/arm/mm/proc.S
108 	 */
109 	cpu_info = lookup_processor_type(read_cpuid_id());
110 	if (!cpu_info) {
111 		printk("CPU configuration botched (ID %08x), unable to continue.\n",
112 		       read_cpuid_id());
113 		while (1);
114 	}
115 
116 	cpu_name = cpu_info->cpu_name;
117 
118 	printk("CPU: %s [%08x] revision %d\n",
119 	       cpu_name, read_cpuid_id(), read_cpuid_id() & 15);
120 
121 	sprintf(init_utsname()->machine, "aarch64");
122 	elf_hwcap = 0;
123 }
124 
125 static void __init setup_machine_fdt(phys_addr_t dt_phys)
126 {
127 	struct boot_param_header *devtree;
128 	unsigned long dt_root;
129 
130 	/* Check we have a non-NULL DT pointer */
131 	if (!dt_phys) {
132 		early_print("\n"
133 			"Error: NULL or invalid device tree blob\n"
134 			"The dtb must be 8-byte aligned and passed in the first 512MB of memory\n"
135 			"\nPlease check your bootloader.\n");
136 
137 		while (true)
138 			cpu_relax();
139 
140 	}
141 
142 	devtree = phys_to_virt(dt_phys);
143 
144 	/* Check device tree validity */
145 	if (be32_to_cpu(devtree->magic) != OF_DT_HEADER) {
146 		early_print("\n"
147 			"Error: invalid device tree blob at physical address 0x%p (virtual address 0x%p)\n"
148 			"Expected 0x%x, found 0x%x\n"
149 			"\nPlease check your bootloader.\n",
150 			dt_phys, devtree, OF_DT_HEADER,
151 			be32_to_cpu(devtree->magic));
152 
153 		while (true)
154 			cpu_relax();
155 	}
156 
157 	initial_boot_params = devtree;
158 	dt_root = of_get_flat_dt_root();
159 
160 	machine_name = of_get_flat_dt_prop(dt_root, "model", NULL);
161 	if (!machine_name)
162 		machine_name = of_get_flat_dt_prop(dt_root, "compatible", NULL);
163 	if (!machine_name)
164 		machine_name = "<unknown>";
165 	pr_info("Machine: %s\n", machine_name);
166 
167 	/* Retrieve various information from the /chosen node */
168 	of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line);
169 	/* Initialize {size,address}-cells info */
170 	of_scan_flat_dt(early_init_dt_scan_root, NULL);
171 	/* Setup memory, calling early_init_dt_add_memory_arch */
172 	of_scan_flat_dt(early_init_dt_scan_memory, NULL);
173 }
174 
175 void __init early_init_dt_add_memory_arch(u64 base, u64 size)
176 {
177 	base &= PAGE_MASK;
178 	size &= PAGE_MASK;
179 	if (base + size < PHYS_OFFSET) {
180 		pr_warning("Ignoring memory block 0x%llx - 0x%llx\n",
181 			   base, base + size);
182 		return;
183 	}
184 	if (base < PHYS_OFFSET) {
185 		pr_warning("Ignoring memory range 0x%llx - 0x%llx\n",
186 			   base, PHYS_OFFSET);
187 		size -= PHYS_OFFSET - base;
188 		base = PHYS_OFFSET;
189 	}
190 	memblock_add(base, size);
191 }
192 
193 void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
194 {
195 	return __va(memblock_alloc(size, align));
196 }
197 
198 /*
199  * Limit the memory size that was specified via FDT.
200  */
201 static int __init early_mem(char *p)
202 {
203 	phys_addr_t limit;
204 
205 	if (!p)
206 		return 1;
207 
208 	limit = memparse(p, &p) & PAGE_MASK;
209 	pr_notice("Memory limited to %lldMB\n", limit >> 20);
210 
211 	memblock_enforce_memory_limit(limit);
212 
213 	return 0;
214 }
215 early_param("mem", early_mem);
216 
217 static void __init request_standard_resources(void)
218 {
219 	struct memblock_region *region;
220 	struct resource *res;
221 
222 	kernel_code.start   = virt_to_phys(_text);
223 	kernel_code.end     = virt_to_phys(_etext - 1);
224 	kernel_data.start   = virt_to_phys(_sdata);
225 	kernel_data.end     = virt_to_phys(_end - 1);
226 
227 	for_each_memblock(memory, region) {
228 		res = alloc_bootmem_low(sizeof(*res));
229 		res->name  = "System RAM";
230 		res->start = __pfn_to_phys(memblock_region_memory_base_pfn(region));
231 		res->end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1;
232 		res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
233 
234 		request_resource(&iomem_resource, res);
235 
236 		if (kernel_code.start >= res->start &&
237 		    kernel_code.end <= res->end)
238 			request_resource(res, &kernel_code);
239 		if (kernel_data.start >= res->start &&
240 		    kernel_data.end <= res->end)
241 			request_resource(res, &kernel_data);
242 	}
243 }
244 
245 u64 __cpu_logical_map[NR_CPUS] = { [0 ... NR_CPUS-1] = INVALID_HWID };
246 
247 void __init setup_arch(char **cmdline_p)
248 {
249 	setup_processor();
250 
251 	setup_machine_fdt(__fdt_pointer);
252 
253 	init_mm.start_code = (unsigned long) _text;
254 	init_mm.end_code   = (unsigned long) _etext;
255 	init_mm.end_data   = (unsigned long) _edata;
256 	init_mm.brk	   = (unsigned long) _end;
257 
258 	*cmdline_p = boot_command_line;
259 
260 	parse_early_param();
261 
262 	arm64_memblock_init();
263 
264 	paging_init();
265 	request_standard_resources();
266 
267 	unflatten_device_tree();
268 
269 	psci_init();
270 
271 	cpu_logical_map(0) = read_cpuid_mpidr() & MPIDR_HWID_BITMASK;
272 #ifdef CONFIG_SMP
273 	smp_init_cpus();
274 #endif
275 
276 #ifdef CONFIG_VT
277 #if defined(CONFIG_VGA_CONSOLE)
278 	conswitchp = &vga_con;
279 #elif defined(CONFIG_DUMMY_CONSOLE)
280 	conswitchp = &dummy_con;
281 #endif
282 #endif
283 }
284 
285 static int __init arm64_device_init(void)
286 {
287 	of_clk_init(NULL);
288 	of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
289 	return 0;
290 }
291 arch_initcall(arm64_device_init);
292 
293 static DEFINE_PER_CPU(struct cpu, cpu_data);
294 
295 static int __init topology_init(void)
296 {
297 	int i;
298 
299 	for_each_possible_cpu(i) {
300 		struct cpu *cpu = &per_cpu(cpu_data, i);
301 		cpu->hotpluggable = 1;
302 		register_cpu(cpu, i);
303 	}
304 
305 	return 0;
306 }
307 subsys_initcall(topology_init);
308 
309 static const char *hwcap_str[] = {
310 	"fp",
311 	"asimd",
312 	NULL
313 };
314 
315 static int c_show(struct seq_file *m, void *v)
316 {
317 	int i;
318 
319 	seq_printf(m, "Processor\t: %s rev %d (%s)\n",
320 		   cpu_name, read_cpuid_id() & 15, ELF_PLATFORM);
321 
322 	for_each_online_cpu(i) {
323 		/*
324 		 * glibc reads /proc/cpuinfo to determine the number of
325 		 * online processors, looking for lines beginning with
326 		 * "processor".  Give glibc what it expects.
327 		 */
328 #ifdef CONFIG_SMP
329 		seq_printf(m, "processor\t: %d\n", i);
330 #endif
331 		seq_printf(m, "BogoMIPS\t: %lu.%02lu\n\n",
332 			   loops_per_jiffy / (500000UL/HZ),
333 			   loops_per_jiffy / (5000UL/HZ) % 100);
334 	}
335 
336 	/* dump out the processor features */
337 	seq_puts(m, "Features\t: ");
338 
339 	for (i = 0; hwcap_str[i]; i++)
340 		if (elf_hwcap & (1 << i))
341 			seq_printf(m, "%s ", hwcap_str[i]);
342 
343 	seq_printf(m, "\nCPU implementer\t: 0x%02x\n", read_cpuid_id() >> 24);
344 	seq_printf(m, "CPU architecture: AArch64\n");
345 	seq_printf(m, "CPU variant\t: 0x%x\n", (read_cpuid_id() >> 20) & 15);
346 	seq_printf(m, "CPU part\t: 0x%03x\n", (read_cpuid_id() >> 4) & 0xfff);
347 	seq_printf(m, "CPU revision\t: %d\n", read_cpuid_id() & 15);
348 
349 	seq_puts(m, "\n");
350 
351 	seq_printf(m, "Hardware\t: %s\n", machine_name);
352 
353 	return 0;
354 }
355 
356 static void *c_start(struct seq_file *m, loff_t *pos)
357 {
358 	return *pos < 1 ? (void *)1 : NULL;
359 }
360 
361 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
362 {
363 	++*pos;
364 	return NULL;
365 }
366 
367 static void c_stop(struct seq_file *m, void *v)
368 {
369 }
370 
371 const struct seq_operations cpuinfo_op = {
372 	.start	= c_start,
373 	.next	= c_next,
374 	.stop	= c_stop,
375 	.show	= c_show
376 };
377