// 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/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 int __init dt_scan_depth1_nodes(unsigned long node,
const char *uname, int depth,
void *data)
{
/*
* Ignore anything not directly under the root node; we'll
* catch its parent instead.
*/
if (depth != 1)
return 0;
if (strcmp(uname, "chosen") == 0)
return 0;
if (strcmp(uname, "hypervisor") == 0 &&
of_flat_dt_is_compatible(node, "xen,xen"))
return 0;
/*
* This node at depth 1 is neither a chosen node nor a xen node,
* which we do not expect.
*/
return 1;
}
/*
* __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 &&
of_scan_flat_dt(dt_scan_depth1_nodes, NULL)))
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);
}
}
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. We use the most efficient capability.
*/
u64 attr;
attr = efi_mem_attributes(addr);
if (attr & EFI_MEMORY_WB)
return PAGE_KERNEL;
if (attr & EFI_MEMORY_WT)
return __pgprot(PROT_NORMAL_WT);
if (attr & EFI_MEMORY_WC)
return __pgprot(PROT_NORMAL_NC);
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:
pr_warn(FW_BUG "requested region covers kernel memory @ %pa\n", &phys);
return NULL;
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_WT)
prot = __pgprot(PROT_NORMAL_WT);
else if (region->attribute & EFI_MEMORY_WC)
prot = __pgprot(PROT_NORMAL_NC);
}
}
return __ioremap(phys, size, 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;
}
