diff options
Diffstat (limited to 'arch/arm64/kernel/setup.c')
-rw-r--r-- | arch/arm64/kernel/setup.c | 459 |
1 files changed, 459 insertions, 0 deletions
diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c new file mode 100644 index 0000000000..417a8a86b2 --- /dev/null +++ b/arch/arm64/kernel/setup.c @@ -0,0 +1,459 @@ +// 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/panic_notifier.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/scs.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/scs.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; +u64 mmu_enabled_at_boot __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; + set_cpu_logical_map(0, mpidr); + + 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 *early_fdt_ptr __initdata; + +void __init *get_early_fdt_ptr(void) +{ + return early_fdt_ptr; +} + +asmlinkage void __init early_fdt_map(u64 dt_phys) +{ + int fdt_size; + + early_fixmap_init(); + early_fdt_ptr = fixmap_remap_fdt(dt_phys, &fdt_size, PAGE_KERNEL); +} + +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%px)\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); + + /* + * Note that in this _really_ early stage we cannot even BUG() + * or oops, so the least terrible thing to do is cpu_relax(), + * or else we could end-up printing non-initialized data, etc. + */ + 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(_stext); + kernel_code.end = __pa_symbol(__init_begin - 1); + kernel_data.start = __pa_symbol(_sdata); + kernel_data.end = __pa_symbol(_end - 1); + insert_resource(&iomem_resource, &kernel_code); + insert_resource(&iomem_resource, &kernel_data); + + 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_mem_region(region) { + res = &standard_resources[i++]; + if (memblock_is_nomap(region)) { + res->name = "reserved"; + res->flags = IORESOURCE_MEM; + res->start = __pfn_to_phys(memblock_region_reserved_base_pfn(region)); + res->end = __pfn_to_phys(memblock_region_reserved_end_pfn(region)) - 1; + } 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; + } + + insert_resource(&iomem_resource, res); + } +} + +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_range(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 }; + +u64 cpu_logical_map(unsigned int cpu) +{ + return __cpu_logical_map[cpu]; +} + +void __init __no_sanitize_address setup_arch(char **cmdline_p) +{ + setup_initial_init_mm(_stext, _etext, _edata, _end); + + *cmdline_p = boot_command_line; + + kaslr_init(); + + /* + * 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(); + + dynamic_scs_init(); + + /* + * 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)) { + if ((u64)_text % MIN_KIMG_ALIGN) + pr_warn(FW_BUG "Kernel image misaligned at boot, please fix your bootloader!"); + WARN_TAINT(mmu_enabled_at_boot, TAINT_FIRMWARE_WORKAROUND, + FW_BUG "Booted with MMU enabled!"); + } + + 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_sw_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 = phys_to_ttbr(__pa_symbol(reserved_pg_dir)); +#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_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); + +static void dump_kernel_offset(void) +{ + 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"); + } +} + +static int arm64_panic_block_dump(struct notifier_block *self, + unsigned long v, void *p) +{ + dump_kernel_offset(); + dump_cpu_features(); + dump_mem_limit(); + return 0; +} + +static struct notifier_block arm64_panic_block = { + .notifier_call = arm64_panic_block_dump +}; + +static int __init register_arm64_panic_block(void) +{ + atomic_notifier_chain_register(&panic_notifier_list, + &arm64_panic_block); + return 0; +} +device_initcall(register_arm64_panic_block); + +static int __init check_mmu_enabled_at_boot(void) +{ + if (!efi_enabled(EFI_BOOT) && mmu_enabled_at_boot) + panic("Non-EFI boot detected with MMU and caches enabled"); + return 0; +} +device_initcall_sync(check_mmu_enabled_at_boot); |