xref: /openbmc/linux/arch/arm64/kernel/setup.c (revision 77d84ff8)
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/cpu_ops.h>
49 #include <asm/sections.h>
50 #include <asm/setup.h>
51 #include <asm/smp_plat.h>
52 #include <asm/cacheflush.h>
53 #include <asm/tlbflush.h>
54 #include <asm/traps.h>
55 #include <asm/memblock.h>
56 #include <asm/psci.h>
57 
58 unsigned int processor_id;
59 EXPORT_SYMBOL(processor_id);
60 
61 unsigned long elf_hwcap __read_mostly;
62 EXPORT_SYMBOL_GPL(elf_hwcap);
63 
64 #ifdef CONFIG_COMPAT
65 #define COMPAT_ELF_HWCAP_DEFAULT	\
66 				(COMPAT_HWCAP_HALF|COMPAT_HWCAP_THUMB|\
67 				 COMPAT_HWCAP_FAST_MULT|COMPAT_HWCAP_EDSP|\
68 				 COMPAT_HWCAP_TLS|COMPAT_HWCAP_VFP|\
69 				 COMPAT_HWCAP_VFPv3|COMPAT_HWCAP_VFPv4|\
70 				 COMPAT_HWCAP_NEON|COMPAT_HWCAP_IDIV)
71 unsigned int compat_elf_hwcap __read_mostly = COMPAT_ELF_HWCAP_DEFAULT;
72 #endif
73 
74 static const char *cpu_name;
75 static const char *machine_name;
76 phys_addr_t __fdt_pointer __initdata;
77 
78 /*
79  * Standard memory resources
80  */
81 static struct resource mem_res[] = {
82 	{
83 		.name = "Kernel code",
84 		.start = 0,
85 		.end = 0,
86 		.flags = IORESOURCE_MEM
87 	},
88 	{
89 		.name = "Kernel data",
90 		.start = 0,
91 		.end = 0,
92 		.flags = IORESOURCE_MEM
93 	}
94 };
95 
96 #define kernel_code mem_res[0]
97 #define kernel_data mem_res[1]
98 
99 void __init early_print(const char *str, ...)
100 {
101 	char buf[256];
102 	va_list ap;
103 
104 	va_start(ap, str);
105 	vsnprintf(buf, sizeof(buf), str, ap);
106 	va_end(ap);
107 
108 	printk("%s", buf);
109 }
110 
111 bool arch_match_cpu_phys_id(int cpu, u64 phys_id)
112 {
113 	return phys_id == cpu_logical_map(cpu);
114 }
115 
116 static void __init setup_processor(void)
117 {
118 	struct cpu_info *cpu_info;
119 
120 	/*
121 	 * locate processor in the list of supported processor
122 	 * types.  The linker builds this table for us from the
123 	 * entries in arch/arm/mm/proc.S
124 	 */
125 	cpu_info = lookup_processor_type(read_cpuid_id());
126 	if (!cpu_info) {
127 		printk("CPU configuration botched (ID %08x), unable to continue.\n",
128 		       read_cpuid_id());
129 		while (1);
130 	}
131 
132 	cpu_name = cpu_info->cpu_name;
133 
134 	printk("CPU: %s [%08x] revision %d\n",
135 	       cpu_name, read_cpuid_id(), read_cpuid_id() & 15);
136 
137 	sprintf(init_utsname()->machine, ELF_PLATFORM);
138 	elf_hwcap = 0;
139 }
140 
141 static void __init setup_machine_fdt(phys_addr_t dt_phys)
142 {
143 	if (!dt_phys || !early_init_dt_scan(phys_to_virt(dt_phys))) {
144 		early_print("\n"
145 			"Error: invalid device tree blob at physical address 0x%p (virtual address 0x%p)\n"
146 			"The dtb must be 8-byte aligned and passed in the first 512MB of memory\n"
147 			"\nPlease check your bootloader.\n",
148 			dt_phys, phys_to_virt(dt_phys));
149 
150 		while (true)
151 			cpu_relax();
152 	}
153 
154 	machine_name = of_flat_dt_get_machine_name();
155 }
156 
157 /*
158  * Limit the memory size that was specified via FDT.
159  */
160 static int __init early_mem(char *p)
161 {
162 	phys_addr_t limit;
163 
164 	if (!p)
165 		return 1;
166 
167 	limit = memparse(p, &p) & PAGE_MASK;
168 	pr_notice("Memory limited to %lldMB\n", limit >> 20);
169 
170 	memblock_enforce_memory_limit(limit);
171 
172 	return 0;
173 }
174 early_param("mem", early_mem);
175 
176 static void __init request_standard_resources(void)
177 {
178 	struct memblock_region *region;
179 	struct resource *res;
180 
181 	kernel_code.start   = virt_to_phys(_text);
182 	kernel_code.end     = virt_to_phys(_etext - 1);
183 	kernel_data.start   = virt_to_phys(_sdata);
184 	kernel_data.end     = virt_to_phys(_end - 1);
185 
186 	for_each_memblock(memory, region) {
187 		res = alloc_bootmem_low(sizeof(*res));
188 		res->name  = "System RAM";
189 		res->start = __pfn_to_phys(memblock_region_memory_base_pfn(region));
190 		res->end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1;
191 		res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
192 
193 		request_resource(&iomem_resource, res);
194 
195 		if (kernel_code.start >= res->start &&
196 		    kernel_code.end <= res->end)
197 			request_resource(res, &kernel_code);
198 		if (kernel_data.start >= res->start &&
199 		    kernel_data.end <= res->end)
200 			request_resource(res, &kernel_data);
201 	}
202 }
203 
204 u64 __cpu_logical_map[NR_CPUS] = { [0 ... NR_CPUS-1] = INVALID_HWID };
205 
206 void __init setup_arch(char **cmdline_p)
207 {
208 	/*
209 	 * Unmask asynchronous aborts early to catch possible system errors.
210 	 */
211 	local_async_enable();
212 
213 	setup_processor();
214 
215 	setup_machine_fdt(__fdt_pointer);
216 
217 	init_mm.start_code = (unsigned long) _text;
218 	init_mm.end_code   = (unsigned long) _etext;
219 	init_mm.end_data   = (unsigned long) _edata;
220 	init_mm.brk	   = (unsigned long) _end;
221 
222 	*cmdline_p = boot_command_line;
223 
224 	parse_early_param();
225 
226 	arm64_memblock_init();
227 
228 	paging_init();
229 	request_standard_resources();
230 
231 	unflatten_device_tree();
232 
233 	psci_init();
234 
235 	cpu_logical_map(0) = read_cpuid_mpidr() & MPIDR_HWID_BITMASK;
236 	cpu_read_bootcpu_ops();
237 #ifdef CONFIG_SMP
238 	smp_init_cpus();
239 #endif
240 
241 #ifdef CONFIG_VT
242 #if defined(CONFIG_VGA_CONSOLE)
243 	conswitchp = &vga_con;
244 #elif defined(CONFIG_DUMMY_CONSOLE)
245 	conswitchp = &dummy_con;
246 #endif
247 #endif
248 }
249 
250 static int __init arm64_device_init(void)
251 {
252 	of_clk_init(NULL);
253 	of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
254 	return 0;
255 }
256 arch_initcall(arm64_device_init);
257 
258 static DEFINE_PER_CPU(struct cpu, cpu_data);
259 
260 static int __init topology_init(void)
261 {
262 	int i;
263 
264 	for_each_possible_cpu(i) {
265 		struct cpu *cpu = &per_cpu(cpu_data, i);
266 		cpu->hotpluggable = 1;
267 		register_cpu(cpu, i);
268 	}
269 
270 	return 0;
271 }
272 subsys_initcall(topology_init);
273 
274 static const char *hwcap_str[] = {
275 	"fp",
276 	"asimd",
277 	"evtstrm",
278 	NULL
279 };
280 
281 static int c_show(struct seq_file *m, void *v)
282 {
283 	int i;
284 
285 	seq_printf(m, "Processor\t: %s rev %d (%s)\n",
286 		   cpu_name, read_cpuid_id() & 15, ELF_PLATFORM);
287 
288 	for_each_online_cpu(i) {
289 		/*
290 		 * glibc reads /proc/cpuinfo to determine the number of
291 		 * online processors, looking for lines beginning with
292 		 * "processor".  Give glibc what it expects.
293 		 */
294 #ifdef CONFIG_SMP
295 		seq_printf(m, "processor\t: %d\n", i);
296 #endif
297 	}
298 
299 	/* dump out the processor features */
300 	seq_puts(m, "Features\t: ");
301 
302 	for (i = 0; hwcap_str[i]; i++)
303 		if (elf_hwcap & (1 << i))
304 			seq_printf(m, "%s ", hwcap_str[i]);
305 
306 	seq_printf(m, "\nCPU implementer\t: 0x%02x\n", read_cpuid_id() >> 24);
307 	seq_printf(m, "CPU architecture: AArch64\n");
308 	seq_printf(m, "CPU variant\t: 0x%x\n", (read_cpuid_id() >> 20) & 15);
309 	seq_printf(m, "CPU part\t: 0x%03x\n", (read_cpuid_id() >> 4) & 0xfff);
310 	seq_printf(m, "CPU revision\t: %d\n", read_cpuid_id() & 15);
311 
312 	seq_puts(m, "\n");
313 
314 	seq_printf(m, "Hardware\t: %s\n", machine_name);
315 
316 	return 0;
317 }
318 
319 static void *c_start(struct seq_file *m, loff_t *pos)
320 {
321 	return *pos < 1 ? (void *)1 : NULL;
322 }
323 
324 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
325 {
326 	++*pos;
327 	return NULL;
328 }
329 
330 static void c_stop(struct seq_file *m, void *v)
331 {
332 }
333 
334 const struct seq_operations cpuinfo_op = {
335 	.start	= c_start,
336 	.next	= c_next,
337 	.stop	= c_stop,
338 	.show	= c_show
339 };
340