// SPDX-License-Identifier: GPL-2.0-only /* * RISC-V Specific Low-Level ACPI Boot Support * * Copyright (C) 2013-2014, Linaro Ltd. * Author: Al Stone * Author: Graeme Gregory * Author: Hanjun Guo * Author: Tomasz Nowicki * Author: Naresh Bhat * * Copyright (C) 2021-2023, Ventana Micro Systems Inc. * Author: Sunil V L */ #include #include #include #include #include #include #include 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 struct acpi_madt_rintc cpu_madt_rintc[NR_CPUS]; 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 return -EINVAL; /* Core will print when we return error */ return 0; } early_param("acpi", parse_acpi); /* * 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 riscv; 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; /* * The revision in the table header is the FADT's Major revision. The * FADT also has a minor revision, which is stored in the FADT itself. * * TODO: Currently, we check for 6.5 as the minimum version to check * for HW_REDUCED flag. However, once RISC-V updates are released in * the ACPI spec, we need to update this check for exact minor revision */ if (table->revision < 6 || (table->revision == 6 && fadt->minor_revision < 5)) pr_err(FW_BUG "Unsupported FADT revision %d.%d, should be 6.5+\n", table->revision, fadt->minor_revision); if (!(fadt->flags & ACPI_FADT_HW_REDUCED)) { pr_err("FADT not ACPI hardware reduced compliant\n"); ret = -EINVAL; } /* * 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 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 * - firmware has not populated ACPI ptr in EFI system table * and ACPI has not been [force] enabled (acpi=on|force) */ if (param_acpi_off || (!param_acpi_on && !param_acpi_force && efi.acpi20 == EFI_INVALID_TABLE_ADDR)) 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 { acpi_parse_spcr(earlycon_acpi_spcr_enable, true); } } static int acpi_parse_madt_rintc(union acpi_subtable_headers *header, const unsigned long end) { struct acpi_madt_rintc *rintc = (struct acpi_madt_rintc *)header; int cpuid; if (!(rintc->flags & ACPI_MADT_ENABLED)) return 0; cpuid = riscv_hartid_to_cpuid(rintc->hart_id); /* * When CONFIG_SMP is disabled, mapping won't be created for * all cpus. * CPUs more than num_possible_cpus, will be ignored. */ if (cpuid >= 0 && cpuid < num_possible_cpus()) cpu_madt_rintc[cpuid] = *rintc; return 0; } /* * Instead of parsing (and freeing) the ACPI table, cache * the RINTC structures since they are frequently used * like in cpuinfo. */ void __init acpi_init_rintc_map(void) { if (acpi_table_parse_madt(ACPI_MADT_TYPE_RINTC, acpi_parse_madt_rintc, 0) <= 0) { pr_err("No valid RINTC entries exist\n"); BUG(); } } struct acpi_madt_rintc *acpi_cpu_get_madt_rintc(int cpu) { return &cpu_madt_rintc[cpu]; } /* * __acpi_map_table() will be called before paging_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_ioremap(phys, size); } void __init __acpi_unmap_table(void __iomem *map, unsigned long size) { if (!map || !size) return; early_iounmap(map, size); } 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 = PAGE_KERNEL_IO; 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\n"); 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. * This particular use case only requires read access. */ 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 *)__va(phys); fallthrough; default: if (region->attribute & EFI_MEMORY_WB) prot = PAGE_KERNEL; else if ((region->attribute & EFI_MEMORY_WC) || (region->attribute & EFI_MEMORY_WT)) prot = pgprot_writecombine(PAGE_KERNEL); } } return ioremap_prot(phys, size, pgprot_val(prot)); } #ifdef CONFIG_PCI /* * raw_pci_read/write - Platform-specific PCI config space access. */ int raw_pci_read(unsigned int domain, unsigned int bus, unsigned int devfn, int reg, int len, u32 *val) { struct pci_bus *b = pci_find_bus(domain, bus); if (!b) return PCIBIOS_DEVICE_NOT_FOUND; return b->ops->read(b, devfn, reg, len, val); } int raw_pci_write(unsigned int domain, unsigned int bus, unsigned int devfn, int reg, int len, u32 val) { struct pci_bus *b = pci_find_bus(domain, bus); if (!b) return PCIBIOS_DEVICE_NOT_FOUND; return b->ops->write(b, devfn, reg, len, val); } #endif /* CONFIG_PCI */