2 * Based on arch/arm/kernel/setup.c
4 * Copyright (C) 1995-2001 Russell King
5 * Copyright (C) 2012 ARM Ltd.
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.
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.
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/>.
20 #include <linux/acpi.h>
21 #include <linux/export.h>
22 #include <linux/kernel.h>
23 #include <linux/stddef.h>
24 #include <linux/ioport.h>
25 #include <linux/delay.h>
26 #include <linux/utsname.h>
27 #include <linux/initrd.h>
28 #include <linux/console.h>
29 #include <linux/cache.h>
30 #include <linux/bootmem.h>
31 #include <linux/seq_file.h>
32 #include <linux/screen_info.h>
33 #include <linux/init.h>
34 #include <linux/kexec.h>
35 #include <linux/crash_dump.h>
36 #include <linux/root_dev.h>
37 #include <linux/cpu.h>
38 #include <linux/interrupt.h>
39 #include <linux/smp.h>
41 #include <linux/proc_fs.h>
42 #include <linux/memblock.h>
43 #include <linux/of_iommu.h>
44 #include <linux/of_fdt.h>
45 #include <linux/of_platform.h>
46 #include <linux/efi.h>
47 #include <linux/personality.h>
48 #include <linux/psci.h>
51 #include <asm/fixmap.h>
53 #include <asm/cputype.h>
55 #include <asm/cpufeature.h>
56 #include <asm/cpu_ops.h>
57 #include <asm/kasan.h>
58 #include <asm/sections.h>
59 #include <asm/setup.h>
60 #include <asm/smp_plat.h>
61 #include <asm/cacheflush.h>
62 #include <asm/tlbflush.h>
63 #include <asm/traps.h>
64 #include <asm/memblock.h>
66 #include <asm/xen/hypervisor.h>
68 phys_addr_t __fdt_pointer __initdata;
71 * Standard memory resources
73 static struct resource mem_res[] = {
75 .name = "Kernel code",
78 .flags = IORESOURCE_MEM
81 .name = "Kernel data",
84 .flags = IORESOURCE_MEM
88 #define kernel_code mem_res[0]
89 #define kernel_data mem_res[1]
92 * The recorded values of x0 .. x3 upon kernel entry.
94 u64 __cacheline_aligned boot_args[4];
96 void __init smp_setup_processor_id(void)
98 u64 mpidr = read_cpuid_mpidr() & MPIDR_HWID_BITMASK;
99 cpu_logical_map(0) = mpidr;
102 * clear __my_cpu_offset on boot CPU to avoid hang caused by
103 * using percpu variable early, for example, lockdep will
104 * access percpu variable inside lock_release
106 set_my_cpu_offset(0);
107 pr_info("Booting Linux on physical CPU 0x%lx\n", (unsigned long)mpidr);
110 bool arch_match_cpu_phys_id(int cpu, u64 phys_id)
112 return phys_id == cpu_logical_map(cpu);
115 struct mpidr_hash mpidr_hash;
117 * smp_build_mpidr_hash - Pre-compute shifts required at each affinity
118 * level in order to build a linear index from an
119 * MPIDR value. Resulting algorithm is a collision
120 * free hash carried out through shifting and ORing
122 static void __init smp_build_mpidr_hash(void)
124 u32 i, affinity, fs[4], bits[4], ls;
127 * Pre-scan the list of MPIDRS and filter out bits that do
128 * not contribute to affinity levels, ie they never toggle.
130 for_each_possible_cpu(i)
131 mask |= (cpu_logical_map(i) ^ cpu_logical_map(0));
132 pr_debug("mask of set bits %#llx\n", mask);
134 * Find and stash the last and first bit set at all affinity levels to
135 * check how many bits are required to represent them.
137 for (i = 0; i < 4; i++) {
138 affinity = MPIDR_AFFINITY_LEVEL(mask, i);
140 * Find the MSB bit and LSB bits position
141 * to determine how many bits are required
142 * to express the affinity level.
145 fs[i] = affinity ? ffs(affinity) - 1 : 0;
146 bits[i] = ls - fs[i];
149 * An index can be created from the MPIDR_EL1 by isolating the
150 * significant bits at each affinity level and by shifting
151 * them in order to compress the 32 bits values space to a
152 * compressed set of values. This is equivalent to hashing
153 * the MPIDR_EL1 through shifting and ORing. It is a collision free
154 * hash though not minimal since some levels might contain a number
155 * of CPUs that is not an exact power of 2 and their bit
156 * representation might contain holes, eg MPIDR_EL1[7:0] = {0x2, 0x80}.
158 mpidr_hash.shift_aff[0] = MPIDR_LEVEL_SHIFT(0) + fs[0];
159 mpidr_hash.shift_aff[1] = MPIDR_LEVEL_SHIFT(1) + fs[1] - bits[0];
160 mpidr_hash.shift_aff[2] = MPIDR_LEVEL_SHIFT(2) + fs[2] -
162 mpidr_hash.shift_aff[3] = MPIDR_LEVEL_SHIFT(3) +
163 fs[3] - (bits[2] + bits[1] + bits[0]);
164 mpidr_hash.mask = mask;
165 mpidr_hash.bits = bits[3] + bits[2] + bits[1] + bits[0];
166 pr_debug("MPIDR hash: aff0[%u] aff1[%u] aff2[%u] aff3[%u] mask[%#llx] bits[%u]\n",
167 mpidr_hash.shift_aff[0],
168 mpidr_hash.shift_aff[1],
169 mpidr_hash.shift_aff[2],
170 mpidr_hash.shift_aff[3],
174 * 4x is an arbitrary value used to warn on a hash table much bigger
175 * than expected on most systems.
177 if (mpidr_hash_size() > 4 * num_possible_cpus())
178 pr_warn("Large number of MPIDR hash buckets detected\n");
179 __flush_dcache_area(&mpidr_hash, sizeof(struct mpidr_hash));
182 static void __init setup_machine_fdt(phys_addr_t dt_phys)
184 void *dt_virt = fixmap_remap_fdt(dt_phys);
186 if (!dt_virt || !early_init_dt_scan(dt_virt)) {
188 "Error: invalid device tree blob at physical address %pa (virtual address 0x%p)\n"
189 "The dtb must be 8-byte aligned and must not exceed 2 MB in size\n"
190 "\nPlease check your bootloader.",
197 dump_stack_set_arch_desc("%s (DT)", of_flat_dt_get_machine_name());
200 static void __init request_standard_resources(void)
202 struct memblock_region *region;
203 struct resource *res;
205 kernel_code.start = virt_to_phys(_text);
206 kernel_code.end = virt_to_phys(_etext - 1);
207 kernel_data.start = virt_to_phys(_sdata);
208 kernel_data.end = virt_to_phys(_end - 1);
210 for_each_memblock(memory, region) {
211 res = alloc_bootmem_low(sizeof(*res));
212 res->name = "System RAM";
213 res->start = __pfn_to_phys(memblock_region_memory_base_pfn(region));
214 res->end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1;
215 res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
217 request_resource(&iomem_resource, res);
219 if (kernel_code.start >= res->start &&
220 kernel_code.end <= res->end)
221 request_resource(res, &kernel_code);
222 if (kernel_data.start >= res->start &&
223 kernel_data.end <= res->end)
224 request_resource(res, &kernel_data);
228 #ifdef CONFIG_BLK_DEV_INITRD
230 * Relocate initrd if it is not completely within the linear mapping.
231 * This would be the case if mem= cuts out all or part of it.
233 static void __init relocate_initrd(void)
235 phys_addr_t orig_start = __virt_to_phys(initrd_start);
236 phys_addr_t orig_end = __virt_to_phys(initrd_end);
237 phys_addr_t ram_end = memblock_end_of_DRAM();
238 phys_addr_t new_start;
239 unsigned long size, to_free = 0;
242 if (orig_end <= ram_end)
246 * Any of the original initrd which overlaps the linear map should
247 * be freed after relocating.
249 if (orig_start < ram_end)
250 to_free = ram_end - orig_start;
252 size = orig_end - orig_start;
254 /* initrd needs to be relocated completely inside linear mapping */
255 new_start = memblock_find_in_range(0, PFN_PHYS(max_pfn),
258 panic("Cannot relocate initrd of size %ld\n", size);
259 memblock_reserve(new_start, size);
261 initrd_start = __phys_to_virt(new_start);
262 initrd_end = initrd_start + size;
264 pr_info("Moving initrd from [%llx-%llx] to [%llx-%llx]\n",
265 orig_start, orig_start + size - 1,
266 new_start, new_start + size - 1);
268 dest = (void *)initrd_start;
271 memcpy(dest, (void *)__phys_to_virt(orig_start), to_free);
275 copy_from_early_mem(dest, orig_start + to_free, size - to_free);
278 pr_info("Freeing original RAMDISK from [%llx-%llx]\n",
279 orig_start, orig_start + to_free - 1);
280 memblock_free(orig_start, to_free);
284 static inline void __init relocate_initrd(void)
289 u64 __cpu_logical_map[NR_CPUS] = { [0 ... NR_CPUS-1] = INVALID_HWID };
291 void __init setup_arch(char **cmdline_p)
293 pr_info("Boot CPU: AArch64 Processor [%08x]\n", read_cpuid_id());
295 sprintf(init_utsname()->machine, ELF_PLATFORM);
296 init_mm.start_code = (unsigned long) _text;
297 init_mm.end_code = (unsigned long) _etext;
298 init_mm.end_data = (unsigned long) _edata;
299 init_mm.brk = (unsigned long) _end;
301 *cmdline_p = boot_command_line;
304 early_ioremap_init();
306 setup_machine_fdt(__fdt_pointer);
311 * Unmask asynchronous aborts after bringing up possible earlycon.
312 * (Report possible System Errors once we can report this occurred)
314 local_async_enable();
317 arm64_memblock_init();
319 /* Parse the ACPI tables for possible boot-time configuration */
320 acpi_boot_table_init();
327 request_standard_resources();
329 early_ioremap_reset();
332 unflatten_device_tree();
339 cpu_read_bootcpu_ops();
341 smp_build_mpidr_hash();
344 #if defined(CONFIG_VGA_CONSOLE)
345 conswitchp = &vga_con;
346 #elif defined(CONFIG_DUMMY_CONSOLE)
347 conswitchp = &dummy_con;
350 if (boot_args[1] || boot_args[2] || boot_args[3]) {
351 pr_err("WARNING: x1-x3 nonzero in violation of boot protocol:\n"
352 "\tx1: %016llx\n\tx2: %016llx\n\tx3: %016llx\n"
353 "This indicates a broken bootloader or old kernel\n",
354 boot_args[1], boot_args[2], boot_args[3]);
358 static int __init arm64_device_init(void)
360 if (of_have_populated_dt()) {
362 of_platform_populate(NULL, of_default_bus_match_table,
364 } else if (acpi_disabled) {
365 pr_crit("Device tree not populated\n");
369 arch_initcall_sync(arm64_device_init);
371 static int __init topology_init(void)
375 for_each_possible_cpu(i) {
376 struct cpu *cpu = &per_cpu(cpu_data.cpu, i);
377 cpu->hotpluggable = 1;
378 register_cpu(cpu, i);
383 subsys_initcall(topology_init);
385 static const char *hwcap_str[] = {
399 static const char *compat_hwcap_str[] = {
424 static const char *compat_hwcap2_str[] = {
432 #endif /* CONFIG_COMPAT */
434 static int c_show(struct seq_file *m, void *v)
438 for_each_online_cpu(i) {
439 struct cpuinfo_arm64 *cpuinfo = &per_cpu(cpu_data, i);
440 u32 midr = cpuinfo->reg_midr;
443 * glibc reads /proc/cpuinfo to determine the number of
444 * online processors, looking for lines beginning with
445 * "processor". Give glibc what it expects.
447 seq_printf(m, "processor\t: %d\n", i);
450 * Dump out the common processor features in a single line.
451 * Userspace should read the hwcaps with getauxval(AT_HWCAP)
452 * rather than attempting to parse this, but there's a body of
453 * software which does already (at least for 32-bit).
455 seq_puts(m, "Features\t:");
456 if (personality(current->personality) == PER_LINUX32) {
458 for (j = 0; compat_hwcap_str[j]; j++)
459 if (compat_elf_hwcap & (1 << j))
460 seq_printf(m, " %s", compat_hwcap_str[j]);
462 for (j = 0; compat_hwcap2_str[j]; j++)
463 if (compat_elf_hwcap2 & (1 << j))
464 seq_printf(m, " %s", compat_hwcap2_str[j]);
465 #endif /* CONFIG_COMPAT */
467 for (j = 0; hwcap_str[j]; j++)
468 if (elf_hwcap & (1 << j))
469 seq_printf(m, " %s", hwcap_str[j]);
473 seq_printf(m, "CPU implementer\t: 0x%02x\n",
474 MIDR_IMPLEMENTOR(midr));
475 seq_printf(m, "CPU architecture: 8\n");
476 seq_printf(m, "CPU variant\t: 0x%x\n", MIDR_VARIANT(midr));
477 seq_printf(m, "CPU part\t: 0x%03x\n", MIDR_PARTNUM(midr));
478 seq_printf(m, "CPU revision\t: %d\n\n", MIDR_REVISION(midr));
484 static void *c_start(struct seq_file *m, loff_t *pos)
486 return *pos < 1 ? (void *)1 : NULL;
489 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
495 static void c_stop(struct seq_file *m, void *v)
499 const struct seq_operations cpuinfo_op = {