// SPDX-License-Identifier: GPL-2.0-only /* * ARM64 Specific Low-Level ACPI Boot Support * * Copyright (C) 2013-2014, Linaro Ltd. * Author: Al Stone <al.stone@linaro.org> * Author: Graeme Gregory <graeme.gregory@linaro.org> * Author: Hanjun Guo <hanjun.guo@linaro.org> * Author: Tomasz Nowicki <tomasz.nowicki@linaro.org> * Author: Naresh Bhat <naresh.bhat@linaro.org> */ #define pr_fmt(fmt) "ACPI: " fmt #include <linux/acpi.h> #include <linux/arm-smccc.h> #include <linux/cpumask.h> #include <linux/efi.h> #include <linux/efi-bgrt.h> #include <linux/init.h> #include <linux/irq.h> #include <linux/irqdomain.h> #include <linux/irq_work.h> #include <linux/memblock.h> #include <linux/of_fdt.h> #include <linux/libfdt.h> #include <linux/smp.h> #include <linux/serial_core.h> #include <linux/suspend.h> #include <linux/pgtable.h> #include <acpi/ghes.h> #include <acpi/processor.h> #include <asm/cputype.h> #include <asm/cpu_ops.h> #include <asm/daifflags.h> #include <asm/smp_plat.h> int acpi_noirq = 1; /* skip ACPI IRQ initialization */ int acpi_disabled = 1; EXPORT_SYMBOL(acpi_disabled); int acpi_pci_disabled = 1; /* skip ACPI PCI scan and IRQ initialization */ EXPORT_SYMBOL(acpi_pci_disabled); static bool param_acpi_off __initdata; static bool param_acpi_on __initdata; static bool param_acpi_force __initdata; static bool param_acpi_nospcr __initdata; static int __init parse_acpi(char *arg) { if (!arg) return -EINVAL; /* "acpi=off" disables both ACPI table parsing and interpreter */ if (strcmp(arg, "off") == 0) param_acpi_off = true; else if (strcmp(arg, "on") == 0) /* prefer ACPI over DT */ param_acpi_on = true; else if (strcmp(arg, "force") == 0) /* force ACPI to be enabled */ param_acpi_force = true; else if (strcmp(arg, "nospcr") == 0) /* disable SPCR as default console */ param_acpi_nospcr = true; else return -EINVAL; /* Core will print when we return error */ return 0; } early_param("acpi", parse_acpi); static bool __init dt_is_stub(void) { int node; fdt_for_each_subnode(node, initial_boot_params, 0) { const char *name = fdt_get_name(initial_boot_params, node, NULL); if (strcmp(name, "chosen") == 0) continue; if (strcmp(name, "hypervisor") == 0 && of_flat_dt_is_compatible(node, "xen,xen")) continue; return false; } return true; } /* * __acpi_map_table() will be called before page_init(), so early_ioremap() * or early_memremap() should be called here to for ACPI table mapping. */ void __init __iomem *__acpi_map_table(unsigned long phys, unsigned long size) { if (!size) return NULL; return early_memremap(phys, size); } void __init __acpi_unmap_table(void __iomem *map, unsigned long size) { if (!map || !size) return; early_memunmap(map, size); } bool __init acpi_psci_present(void) { return acpi_gbl_FADT.arm_boot_flags & ACPI_FADT_PSCI_COMPLIANT; } /* Whether HVC must be used instead of SMC as the PSCI conduit */ bool acpi_psci_use_hvc(void) { return acpi_gbl_FADT.arm_boot_flags & ACPI_FADT_PSCI_USE_HVC; } /* * acpi_fadt_sanity_check() - Check FADT presence and carry out sanity * checks on it * * Return 0 on success, <0 on failure */ static int __init acpi_fadt_sanity_check(void) { struct acpi_table_header *table; struct acpi_table_fadt *fadt; acpi_status status; int ret = 0; /* * FADT is required on arm64; retrieve it to check its presence * and carry out revision and ACPI HW reduced compliancy tests */ status = acpi_get_table(ACPI_SIG_FADT, 0, &table); if (ACPI_FAILURE(status)) { const char *msg = acpi_format_exception(status); pr_err("Failed to get FADT table, %s\n", msg); return -ENODEV; } fadt = (struct acpi_table_fadt *)table; /* * Revision in table header is the FADT Major revision, and there * is a minor revision of FADT which was introduced by ACPI 5.1, * we only deal with ACPI 5.1 or newer revision to get GIC and SMP * boot protocol configuration data. */ if (table->revision < 5 || (table->revision == 5 && fadt->minor_revision < 1)) { pr_err(FW_BUG "Unsupported FADT revision %d.%d, should be 5.1+\n", table->revision, fadt->minor_revision); if (!fadt->arm_boot_flags) { ret = -EINVAL; goto out; } pr_err("FADT has ARM boot flags set, assuming 5.1\n"); } if (!(fadt->flags & ACPI_FADT_HW_REDUCED)) { pr_err("FADT not ACPI hardware reduced compliant\n"); ret = -EINVAL; } out: /* * acpi_get_table() creates FADT table mapping that * should be released after parsing and before resuming boot */ acpi_put_table(table); return ret; } /* * acpi_boot_table_init() called from setup_arch(), always. * 1. find RSDP and get its address, and then find XSDT * 2. extract all tables and checksums them all * 3. check ACPI FADT revision * 4. check ACPI FADT HW reduced flag * * We can parse ACPI boot-time tables such as MADT after * this function is called. * * On return ACPI is enabled if either: * * - ACPI tables are initialized and sanity checks passed * - acpi=force was passed in the command line and ACPI was not disabled * explicitly through acpi=off command line parameter * * ACPI is disabled on function return otherwise */ void __init acpi_boot_table_init(void) { /* * Enable ACPI instead of device tree unless * - ACPI has been disabled explicitly (acpi=off), or * - the device tree is not empty (it has more than just a /chosen node, * and a /hypervisor node when running on Xen) * and ACPI has not been [force] enabled (acpi=on|force) */ if (param_acpi_off || (!param_acpi_on && !param_acpi_force && !dt_is_stub())) goto done; /* * ACPI is disabled at this point. Enable it in order to parse * the ACPI tables and carry out sanity checks */ enable_acpi(); /* * If ACPI tables are initialized and FADT sanity checks passed, * leave ACPI enabled and carry on booting; otherwise disable ACPI * on initialization error. * If acpi=force was passed on the command line it forces ACPI * to be enabled even if its initialization failed. */ if (acpi_table_init() || acpi_fadt_sanity_check()) { pr_err("Failed to init ACPI tables\n"); if (!param_acpi_force) disable_acpi(); } done: if (acpi_disabled) { if (earlycon_acpi_spcr_enable) early_init_dt_scan_chosen_stdout(); } else { #ifdef CONFIG_HIBERNATION struct acpi_table_header *facs = NULL; acpi_get_table(ACPI_SIG_FACS, 1, &facs); if (facs) { swsusp_hardware_signature = ((struct acpi_table_facs *)facs)->hardware_signature; acpi_put_table(facs); } #endif /* * For varying privacy and security reasons, sometimes need * to completely silence the serial console output, and only * enable it when needed. * But there are many existing systems that depend on this * behaviour, use acpi=nospcr to disable console in ACPI SPCR * table as default serial console. */ acpi_parse_spcr(earlycon_acpi_spcr_enable, !param_acpi_nospcr); pr_info("Use ACPI SPCR as default console: %s\n", param_acpi_nospcr ? "No" : "Yes"); if (IS_ENABLED(CONFIG_ACPI_BGRT)) acpi_table_parse(ACPI_SIG_BGRT, acpi_parse_bgrt); } } static pgprot_t __acpi_get_writethrough_mem_attribute(void) { /* * Although UEFI specifies the use of Normal Write-through for * EFI_MEMORY_WT, it is seldom used in practice and not implemented * by most (all?) CPUs. Rather than allocate a MAIR just for this * purpose, emit a warning and use Normal Non-cacheable instead. */ pr_warn_once("No MAIR allocation for EFI_MEMORY_WT; treating as Normal Non-cacheable\n"); return __pgprot(PROT_NORMAL_NC); } pgprot_t __acpi_get_mem_attribute(phys_addr_t addr) { /* * According to "Table 8 Map: EFI memory types to AArch64 memory * types" of UEFI 2.5 section 2.3.6.1, each EFI memory type is * mapped to a corresponding MAIR attribute encoding. * The EFI memory attribute advises all possible capabilities * of a memory region. */ u64 attr; attr = efi_mem_attributes(addr); if (attr & EFI_MEMORY_WB) return PAGE_KERNEL; if (attr & EFI_MEMORY_WC) return __pgprot(PROT_NORMAL_NC); if (attr & EFI_MEMORY_WT) return __acpi_get_writethrough_mem_attribute(); return __pgprot(PROT_DEVICE_nGnRnE); } void __iomem *acpi_os_ioremap(acpi_physical_address phys, acpi_size size) { efi_memory_desc_t *md, *region = NULL; pgprot_t prot; if (WARN_ON_ONCE(!efi_enabled(EFI_MEMMAP))) return NULL; for_each_efi_memory_desc(md) { u64 end = md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT); if (phys < md->phys_addr || phys >= end) continue; if (phys + size > end) { pr_warn(FW_BUG "requested region covers multiple EFI memory regions\n"); return NULL; } region = md; break; } /* * It is fine for AML to remap regions that are not represented in the * EFI memory map at all, as it only describes normal memory, and MMIO * regions that require a virtual mapping to make them accessible to * the EFI runtime services. */ prot = __pgprot(PROT_DEVICE_nGnRnE); if (region) { switch (region->type) { case EFI_LOADER_CODE: case EFI_LOADER_DATA: case EFI_BOOT_SERVICES_CODE: case EFI_BOOT_SERVICES_DATA: case EFI_CONVENTIONAL_MEMORY: case EFI_PERSISTENT_MEMORY: if (memblock_is_map_memory(phys) || !memblock_is_region_memory(phys, size)) { pr_warn(FW_BUG "requested region covers kernel memory @ %pa\n", &phys); return NULL; } /* * Mapping kernel memory is permitted if the region in * question is covered by a single memblock with the * NOMAP attribute set: this enables the use of ACPI * table overrides passed via initramfs, which are * reserved in memory using arch_reserve_mem_area() * below. As this particular use case only requires * read access, fall through to the R/O mapping case. */ fallthrough; case EFI_RUNTIME_SERVICES_CODE: /* * This would be unusual, but not problematic per se, * as long as we take care not to create a writable * mapping for executable code. */ prot = PAGE_KERNEL_RO; break; case EFI_ACPI_RECLAIM_MEMORY: /* * ACPI reclaim memory is used to pass firmware tables * and other data that is intended for consumption by * the OS only, which may decide it wants to reclaim * that memory and use it for something else. We never * do that, but we usually add it to the linear map * anyway, in which case we should use the existing * mapping. */ if (memblock_is_map_memory(phys)) return (void __iomem *)__phys_to_virt(phys); fallthrough; default: if (region->attribute & EFI_MEMORY_WB) prot = PAGE_KERNEL; else if (region->attribute & EFI_MEMORY_WC) prot = __pgprot(PROT_NORMAL_NC); else if (region->attribute & EFI_MEMORY_WT) prot = __acpi_get_writethrough_mem_attribute(); } } return ioremap_prot(phys, size, pgprot_val(prot)); } /* * Claim Synchronous External Aborts as a firmware first notification. * * Used by KVM and the arch do_sea handler. * @regs may be NULL when called from process context. */ int apei_claim_sea(struct pt_regs *regs) { int err = -ENOENT; bool return_to_irqs_enabled; unsigned long current_flags; if (!IS_ENABLED(CONFIG_ACPI_APEI_GHES)) return err; current_flags = local_daif_save_flags(); /* current_flags isn't useful here as daif doesn't tell us about pNMI */ return_to_irqs_enabled = !irqs_disabled_flags(arch_local_save_flags()); if (regs) return_to_irqs_enabled = interrupts_enabled(regs); /* * SEA can interrupt SError, mask it and describe this as an NMI so * that APEI defers the handling. */ local_daif_restore(DAIF_ERRCTX); nmi_enter(); err = ghes_notify_sea(); nmi_exit(); /* * APEI NMI-like notifications are deferred to irq_work. Unless * we interrupted irqs-masked code, we can do that now. */ if (!err) { if (return_to_irqs_enabled) { local_daif_restore(DAIF_PROCCTX_NOIRQ); __irq_enter(); irq_work_run(); __irq_exit(); } else { pr_warn_ratelimited("APEI work queued but not completed"); err = -EINPROGRESS; } } local_daif_restore(current_flags); return err; } void arch_reserve_mem_area(acpi_physical_address addr, size_t size) { memblock_mark_nomap(addr, size); } #ifdef CONFIG_ACPI_HOTPLUG_CPU int acpi_map_cpu(acpi_handle handle, phys_cpuid_t physid, u32 apci_id, int *pcpu) { /* If an error code is passed in this stub can't fix it */ if (*pcpu < 0) { pr_warn_once("Unable to map CPU to valid ID\n"); return *pcpu; } return 0; } EXPORT_SYMBOL(acpi_map_cpu); int acpi_unmap_cpu(int cpu) { return 0; } EXPORT_SYMBOL(acpi_unmap_cpu); #endif /* CONFIG_ACPI_HOTPLUG_CPU */