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-rw-r--r--arch/arm64/kernel/acpi.c413
1 files changed, 413 insertions, 0 deletions
diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c
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index 000000000..a5a256e3f
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+++ b/arch/arm64/kernel/acpi.c
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+// 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/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/pgtable.h>
+
+#include <acpi/ghes.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 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);
+
+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 {
+ acpi_parse_spcr(earlycon_acpi_spcr_enable, true);
+ 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);
+}
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