/arch/arm64/kernel/setup.c
C | 431 lines | 283 code | 67 blank | 81 comment | 32 complexity | a299ce5a8c4d6205d231cd07b8dad3d1 MD5 | raw file
Possible License(s): LGPL-2.0, AGPL-1.0, GPL-2.0
- // SPDX-License-Identifier: GPL-2.0-only
- /*
- * Based on arch/arm/kernel/setup.c
- *
- * Copyright (C) 1995-2001 Russell King
- * Copyright (C) 2012 ARM Ltd.
- */
- #include <linux/acpi.h>
- #include <linux/export.h>
- #include <linux/kernel.h>
- #include <linux/stddef.h>
- #include <linux/ioport.h>
- #include <linux/delay.h>
- #include <linux/initrd.h>
- #include <linux/console.h>
- #include <linux/cache.h>
- #include <linux/screen_info.h>
- #include <linux/init.h>
- #include <linux/kexec.h>
- #include <linux/root_dev.h>
- #include <linux/cpu.h>
- #include <linux/interrupt.h>
- #include <linux/smp.h>
- #include <linux/fs.h>
- #include <linux/proc_fs.h>
- #include <linux/memblock.h>
- #include <linux/of_fdt.h>
- #include <linux/efi.h>
- #include <linux/psci.h>
- #include <linux/sched/task.h>
- #include <linux/mm.h>
- #include <asm/acpi.h>
- #include <asm/fixmap.h>
- #include <asm/cpu.h>
- #include <asm/cputype.h>
- #include <asm/daifflags.h>
- #include <asm/elf.h>
- #include <asm/cpufeature.h>
- #include <asm/cpu_ops.h>
- #include <asm/kasan.h>
- #include <asm/numa.h>
- #include <asm/sections.h>
- #include <asm/setup.h>
- #include <asm/smp_plat.h>
- #include <asm/cacheflush.h>
- #include <asm/tlbflush.h>
- #include <asm/traps.h>
- #include <asm/efi.h>
- #include <asm/xen/hypervisor.h>
- #include <asm/mmu_context.h>
- static int num_standard_resources;
- static struct resource *standard_resources;
- phys_addr_t __fdt_pointer __initdata;
- /*
- * Standard memory resources
- */
- static struct resource mem_res[] = {
- {
- .name = "Kernel code",
- .start = 0,
- .end = 0,
- .flags = IORESOURCE_SYSTEM_RAM
- },
- {
- .name = "Kernel data",
- .start = 0,
- .end = 0,
- .flags = IORESOURCE_SYSTEM_RAM
- }
- };
- #define kernel_code mem_res[0]
- #define kernel_data mem_res[1]
- /*
- * The recorded values of x0 .. x3 upon kernel entry.
- */
- u64 __cacheline_aligned boot_args[4];
- void __init smp_setup_processor_id(void)
- {
- u64 mpidr = read_cpuid_mpidr() & MPIDR_HWID_BITMASK;
- cpu_logical_map(0) = mpidr;
- /*
- * clear __my_cpu_offset on boot CPU to avoid hang caused by
- * using percpu variable early, for example, lockdep will
- * access percpu variable inside lock_release
- */
- set_my_cpu_offset(0);
- pr_info("Booting Linux on physical CPU 0x%010lx [0x%08x]\n",
- (unsigned long)mpidr, read_cpuid_id());
- }
- bool arch_match_cpu_phys_id(int cpu, u64 phys_id)
- {
- return phys_id == cpu_logical_map(cpu);
- }
- struct mpidr_hash mpidr_hash;
- /**
- * smp_build_mpidr_hash - Pre-compute shifts required at each affinity
- * level in order to build a linear index from an
- * MPIDR value. Resulting algorithm is a collision
- * free hash carried out through shifting and ORing
- */
- static void __init smp_build_mpidr_hash(void)
- {
- u32 i, affinity, fs[4], bits[4], ls;
- u64 mask = 0;
- /*
- * Pre-scan the list of MPIDRS and filter out bits that do
- * not contribute to affinity levels, ie they never toggle.
- */
- for_each_possible_cpu(i)
- mask |= (cpu_logical_map(i) ^ cpu_logical_map(0));
- pr_debug("mask of set bits %#llx\n", mask);
- /*
- * Find and stash the last and first bit set at all affinity levels to
- * check how many bits are required to represent them.
- */
- for (i = 0; i < 4; i++) {
- affinity = MPIDR_AFFINITY_LEVEL(mask, i);
- /*
- * Find the MSB bit and LSB bits position
- * to determine how many bits are required
- * to express the affinity level.
- */
- ls = fls(affinity);
- fs[i] = affinity ? ffs(affinity) - 1 : 0;
- bits[i] = ls - fs[i];
- }
- /*
- * An index can be created from the MPIDR_EL1 by isolating the
- * significant bits at each affinity level and by shifting
- * them in order to compress the 32 bits values space to a
- * compressed set of values. This is equivalent to hashing
- * the MPIDR_EL1 through shifting and ORing. It is a collision free
- * hash though not minimal since some levels might contain a number
- * of CPUs that is not an exact power of 2 and their bit
- * representation might contain holes, eg MPIDR_EL1[7:0] = {0x2, 0x80}.
- */
- mpidr_hash.shift_aff[0] = MPIDR_LEVEL_SHIFT(0) + fs[0];
- mpidr_hash.shift_aff[1] = MPIDR_LEVEL_SHIFT(1) + fs[1] - bits[0];
- mpidr_hash.shift_aff[2] = MPIDR_LEVEL_SHIFT(2) + fs[2] -
- (bits[1] + bits[0]);
- mpidr_hash.shift_aff[3] = MPIDR_LEVEL_SHIFT(3) +
- fs[3] - (bits[2] + bits[1] + bits[0]);
- mpidr_hash.mask = mask;
- mpidr_hash.bits = bits[3] + bits[2] + bits[1] + bits[0];
- pr_debug("MPIDR hash: aff0[%u] aff1[%u] aff2[%u] aff3[%u] mask[%#llx] bits[%u]\n",
- mpidr_hash.shift_aff[0],
- mpidr_hash.shift_aff[1],
- mpidr_hash.shift_aff[2],
- mpidr_hash.shift_aff[3],
- mpidr_hash.mask,
- mpidr_hash.bits);
- /*
- * 4x is an arbitrary value used to warn on a hash table much bigger
- * than expected on most systems.
- */
- if (mpidr_hash_size() > 4 * num_possible_cpus())
- pr_warn("Large number of MPIDR hash buckets detected\n");
- }
- static void __init setup_machine_fdt(phys_addr_t dt_phys)
- {
- int size;
- void *dt_virt = fixmap_remap_fdt(dt_phys, &size, PAGE_KERNEL);
- const char *name;
- if (dt_virt)
- memblock_reserve(dt_phys, size);
- if (!dt_virt || !early_init_dt_scan(dt_virt)) {
- pr_crit("\n"
- "Error: invalid device tree blob at physical address %pa (virtual address 0x%p)\n"
- "The dtb must be 8-byte aligned and must not exceed 2 MB in size\n"
- "\nPlease check your bootloader.",
- &dt_phys, dt_virt);
- while (true)
- cpu_relax();
- }
- /* Early fixups are done, map the FDT as read-only now */
- fixmap_remap_fdt(dt_phys, &size, PAGE_KERNEL_RO);
- name = of_flat_dt_get_machine_name();
- if (!name)
- return;
- pr_info("Machine model: %s\n", name);
- dump_stack_set_arch_desc("%s (DT)", name);
- }
- static void __init request_standard_resources(void)
- {
- struct memblock_region *region;
- struct resource *res;
- unsigned long i = 0;
- size_t res_size;
- kernel_code.start = __pa_symbol(_text);
- kernel_code.end = __pa_symbol(__init_begin - 1);
- kernel_data.start = __pa_symbol(_sdata);
- kernel_data.end = __pa_symbol(_end - 1);
- num_standard_resources = memblock.memory.cnt;
- res_size = num_standard_resources * sizeof(*standard_resources);
- standard_resources = memblock_alloc(res_size, SMP_CACHE_BYTES);
- if (!standard_resources)
- panic("%s: Failed to allocate %zu bytes\n", __func__, res_size);
- for_each_memblock(memory, region) {
- res = &standard_resources[i++];
- if (memblock_is_nomap(region)) {
- res->name = "reserved";
- res->flags = IORESOURCE_MEM;
- } else {
- res->name = "System RAM";
- res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
- }
- res->start = __pfn_to_phys(memblock_region_memory_base_pfn(region));
- res->end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1;
- request_resource(&iomem_resource, res);
- if (kernel_code.start >= res->start &&
- kernel_code.end <= res->end)
- request_resource(res, &kernel_code);
- if (kernel_data.start >= res->start &&
- kernel_data.end <= res->end)
- request_resource(res, &kernel_data);
- #ifdef CONFIG_KEXEC_CORE
- /* Userspace will find "Crash kernel" region in /proc/iomem. */
- if (crashk_res.end && crashk_res.start >= res->start &&
- crashk_res.end <= res->end)
- request_resource(res, &crashk_res);
- #endif
- }
- }
- static int __init reserve_memblock_reserved_regions(void)
- {
- u64 i, j;
- for (i = 0; i < num_standard_resources; ++i) {
- struct resource *mem = &standard_resources[i];
- phys_addr_t r_start, r_end, mem_size = resource_size(mem);
- if (!memblock_is_region_reserved(mem->start, mem_size))
- continue;
- for_each_reserved_mem_region(j, &r_start, &r_end) {
- resource_size_t start, end;
- start = max(PFN_PHYS(PFN_DOWN(r_start)), mem->start);
- end = min(PFN_PHYS(PFN_UP(r_end)) - 1, mem->end);
- if (start > mem->end || end < mem->start)
- continue;
- reserve_region_with_split(mem, start, end, "reserved");
- }
- }
- return 0;
- }
- arch_initcall(reserve_memblock_reserved_regions);
- u64 __cpu_logical_map[NR_CPUS] = { [0 ... NR_CPUS-1] = INVALID_HWID };
- void __init setup_arch(char **cmdline_p)
- {
- init_mm.start_code = (unsigned long) _text;
- init_mm.end_code = (unsigned long) _etext;
- init_mm.end_data = (unsigned long) _edata;
- init_mm.brk = (unsigned long) _end;
- *cmdline_p = boot_command_line;
- /*
- * If know now we are going to need KPTI then use non-global
- * mappings from the start, avoiding the cost of rewriting
- * everything later.
- */
- arm64_use_ng_mappings = kaslr_requires_kpti();
- early_fixmap_init();
- early_ioremap_init();
- setup_machine_fdt(__fdt_pointer);
- /*
- * Initialise the static keys early as they may be enabled by the
- * cpufeature code and early parameters.
- */
- jump_label_init();
- parse_early_param();
- /*
- * Unmask asynchronous aborts and fiq after bringing up possible
- * earlycon. (Report possible System Errors once we can report this
- * occurred).
- */
- local_daif_restore(DAIF_PROCCTX_NOIRQ);
- /*
- * TTBR0 is only used for the identity mapping at this stage. Make it
- * point to zero page to avoid speculatively fetching new entries.
- */
- cpu_uninstall_idmap();
- xen_early_init();
- efi_init();
- if (!efi_enabled(EFI_BOOT) && ((u64)_text % MIN_KIMG_ALIGN) != 0)
- pr_warn(FW_BUG "Kernel image misaligned at boot, please fix your bootloader!");
- arm64_memblock_init();
- paging_init();
- acpi_table_upgrade();
- /* Parse the ACPI tables for possible boot-time configuration */
- acpi_boot_table_init();
- if (acpi_disabled)
- unflatten_device_tree();
- bootmem_init();
- kasan_init();
- request_standard_resources();
- early_ioremap_reset();
- if (acpi_disabled)
- psci_dt_init();
- else
- psci_acpi_init();
- init_bootcpu_ops();
- smp_init_cpus();
- smp_build_mpidr_hash();
- /* Init percpu seeds for random tags after cpus are set up. */
- kasan_init_tags();
- #ifdef CONFIG_ARM64_SW_TTBR0_PAN
- /*
- * Make sure init_thread_info.ttbr0 always generates translation
- * faults in case uaccess_enable() is inadvertently called by the init
- * thread.
- */
- init_task.thread_info.ttbr0 = __pa_symbol(empty_zero_page);
- #endif
- if (boot_args[1] || boot_args[2] || boot_args[3]) {
- pr_err("WARNING: x1-x3 nonzero in violation of boot protocol:\n"
- "\tx1: %016llx\n\tx2: %016llx\n\tx3: %016llx\n"
- "This indicates a broken bootloader or old kernel\n",
- boot_args[1], boot_args[2], boot_args[3]);
- }
- }
- static inline bool cpu_can_disable(unsigned int cpu)
- {
- #ifdef CONFIG_HOTPLUG_CPU
- const struct cpu_operations *ops = get_cpu_ops(cpu);
- if (ops && ops->cpu_can_disable)
- return ops->cpu_can_disable(cpu);
- #endif
- return false;
- }
- static int __init topology_init(void)
- {
- int i;
- for_each_online_node(i)
- register_one_node(i);
- for_each_possible_cpu(i) {
- struct cpu *cpu = &per_cpu(cpu_data.cpu, i);
- cpu->hotpluggable = cpu_can_disable(i);
- register_cpu(cpu, i);
- }
- return 0;
- }
- subsys_initcall(topology_init);
- /*
- * Dump out kernel offset information on panic.
- */
- static int dump_kernel_offset(struct notifier_block *self, unsigned long v,
- void *p)
- {
- const unsigned long offset = kaslr_offset();
- if (IS_ENABLED(CONFIG_RANDOMIZE_BASE) && offset > 0) {
- pr_emerg("Kernel Offset: 0x%lx from 0x%lx\n",
- offset, KIMAGE_VADDR);
- pr_emerg("PHYS_OFFSET: 0x%llx\n", PHYS_OFFSET);
- } else {
- pr_emerg("Kernel Offset: disabled\n");
- }
- return 0;
- }
- static struct notifier_block kernel_offset_notifier = {
- .notifier_call = dump_kernel_offset
- };
- static int __init register_kernel_offset_dumper(void)
- {
- atomic_notifier_chain_register(&panic_notifier_list,
- &kernel_offset_notifier);
- return 0;
- }
- __initcall(register_kernel_offset_dumper);