[mirror_ubuntu-jammy-kernel.git] / arch / arm64 / kernel / acpi.c

// 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;
}
Commit	Line	Data
d2912cb1	1	// SPDX-License-Identifier: GPL-2.0-only
37655163 AS	2	/*
	3	* ARM64 Specific Low-Level ACPI Boot Support
	4	*
	5	* Copyright (C) 2013-2014, Linaro Ltd.
	6	* Author: Al Stone <al.stone@linaro.org>
	7	* Author: Graeme Gregory <graeme.gregory@linaro.org>
	8	* Author: Hanjun Guo <hanjun.guo@linaro.org>
	9	* Author: Tomasz Nowicki <tomasz.nowicki@linaro.org>
	10	* Author: Naresh Bhat <naresh.bhat@linaro.org>
37655163 AS	11	*/
	12
	13	#define pr_fmt(fmt) "ACPI: " fmt
	14
	15	#include <linux/acpi.h>
37655163	16	#include <linux/cpumask.h>
09ffcb0d	17	#include <linux/efi.h>
6e7300cf	18	#include <linux/efi-bgrt.h>
37655163 AS	19	#include <linux/init.h>
	20	#include <linux/irq.h>
	21	#include <linux/irqdomain.h>
8fcc4ae6	22	#include <linux/irq_work.h>
37655163	23	#include <linux/memblock.h>
b10d79f7	24	#include <linux/of_fdt.h>
37655163	25	#include <linux/smp.h>
888125a7	26	#include <linux/serial_core.h>
65fddcfc	27	#include <linux/pgtable.h>
37655163	28
d44f1b8d	29	#include <acpi/ghes.h>
fccb9a81 HG	30	#include <asm/cputype.h>
fccb9a81 HG	31	#include <asm/cpu_ops.h>
d44f1b8d	32	#include <asm/daifflags.h>
fccb9a81 HG	33	#include <asm/smp_plat.h>
fccb9a81 HG	34
b10d79f7 AS	35	int acpi_noirq = 1; /* skip ACPI IRQ initialization */
b10d79f7 AS	36	int acpi_disabled = 1;
37655163 AS	37	EXPORT_SYMBOL(acpi_disabled);
37655163 AS	38
b10d79f7	39	int acpi_pci_disabled = 1; /* skip ACPI PCI scan and IRQ initialization */
37655163 AS	40	EXPORT_SYMBOL(acpi_pci_disabled);
37655163 AS	41
b10d79f7	42	static bool param_acpi_off __initdata;
6a1f5471	43	static bool param_acpi_on __initdata;
fb094eb1	44	static bool param_acpi_force __initdata;
b10d79f7 AS	45
	46	static int __init parse_acpi(char *arg)
	47	{
	48	if (!arg)
	49	return -EINVAL;
	50
	51	/* "acpi=off" disables both ACPI table parsing and interpreter */
	52	if (strcmp(arg, "off") == 0)
	53	param_acpi_off = true;
6a1f5471 AB	54	else if (strcmp(arg, "on") == 0) /* prefer ACPI over DT */
6a1f5471 AB	55	param_acpi_on = true;
b10d79f7 AS	56	else if (strcmp(arg, "force") == 0) /* force ACPI to be enabled */
	57	param_acpi_force = true;
	58	else
	59	return -EINVAL; /* Core will print when we return error */
	60
	61	return 0;
	62	}
	63	early_param("acpi", parse_acpi);
	64
	65	static int __init dt_scan_depth1_nodes(unsigned long node,
	66	const char *uname, int depth,
	67	void *data)
	68	{
	69	/*
9981293f MR	70	* Ignore anything not directly under the root node; we'll
9981293f MR	71	* catch its parent instead.
b10d79f7	72	*/
9981293f MR	73	if (depth != 1)
9981293f MR	74	return 0;
2366c7fd	75
9981293f MR	76	if (strcmp(uname, "chosen") == 0)
	77	return 0;
	78
	79	if (strcmp(uname, "hypervisor") == 0 &&
	80	of_flat_dt_is_compatible(node, "xen,xen"))
	81	return 0;
	82
	83	/*
	84	* This node at depth 1 is neither a chosen node nor a xen node,
	85	* which we do not expect.
	86	*/
	87	return 1;
b10d79f7 AS	88	}
b10d79f7 AS	89
37655163 AS	90	/*
	91	* __acpi_map_table() will be called before page_init(), so early_ioremap()
	92	* or early_memremap() should be called here to for ACPI table mapping.
	93	*/
6c9a58e8	94	void __init __iomem *__acpi_map_table(unsigned long phys, unsigned long size)
37655163 AS	95	{
	96	if (!size)
	97	return NULL;
	98
	99	return early_memremap(phys, size);
	100	}
	101
6c9a58e8	102	void __init __acpi_unmap_table(void __iomem *map, unsigned long size)
37655163 AS	103	{
	104	if (!map \|\| !size)
	105	return;
	106
	107	early_memunmap(map, size);
	108	}
	109
c5a13305 MR	110	bool __init acpi_psci_present(void)
	111	{
	112	return acpi_gbl_FADT.arm_boot_flags & ACPI_FADT_PSCI_COMPLIANT;
	113	}
	114
	115	/* Whether HVC must be used instead of SMC as the PSCI conduit */
fa31ab77	116	bool acpi_psci_use_hvc(void)
c5a13305 MR	117	{
	118	return acpi_gbl_FADT.arm_boot_flags & ACPI_FADT_PSCI_USE_HVC;
	119	}
	120
54971e43 LP	121	/*
	122	* acpi_fadt_sanity_check() - Check FADT presence and carry out sanity
	123	* checks on it
	124	*
	125	* Return 0 on success, <0 on failure
	126	*/
	127	static int __init acpi_fadt_sanity_check(void)
37655163	128	{
54971e43 LP	129	struct acpi_table_header *table;
	130	struct acpi_table_fadt *fadt;
	131	acpi_status status;
54971e43 LP	132	int ret = 0;
	133
	134	/*
	135	* FADT is required on arm64; retrieve it to check its presence
	136	* and carry out revision and ACPI HW reduced compliancy tests
	137	*/
6b11d1d6	138	status = acpi_get_table(ACPI_SIG_FADT, 0, &table);
54971e43 LP	139	if (ACPI_FAILURE(status)) {
	140	const char *msg = acpi_format_exception(status);
	141
	142	pr_err("Failed to get FADT table, %s\n", msg);
	143	return -ENODEV;
	144	}
	145
	146	fadt = (struct acpi_table_fadt *)table;
37655163 AS	147
	148	/*
	149	* Revision in table header is the FADT Major revision, and there
	150	* is a minor revision of FADT which was introduced by ACPI 5.1,
	151	* we only deal with ACPI 5.1 or newer revision to get GIC and SMP
54971e43	152	* boot protocol configuration data.
37655163	153	*/
54971e43 LP	154	if (table->revision < 5 \|\|
54971e43 LP	155	(table->revision == 5 && fadt->minor_revision < 1)) {
2af22f3e	156	pr_err(FW_BUG "Unsupported FADT revision %d.%d, should be 5.1+\n",
54971e43	157	table->revision, fadt->minor_revision);
2af22f3e AB	158
	159	if (!fadt->arm_boot_flags) {
	160	ret = -EINVAL;
	161	goto out;
	162	}
	163	pr_err("FADT has ARM boot flags set, assuming 5.1\n");
fccb9a81	164	}
37655163	165
54971e43 LP	166	if (!(fadt->flags & ACPI_FADT_HW_REDUCED)) {
	167	pr_err("FADT not ACPI hardware reduced compliant\n");
	168	ret = -EINVAL;
	169	}
37655163	170
54971e43 LP	171	out:
54971e43 LP	172	/*
6b11d1d6	173	* acpi_get_table() creates FADT table mapping that
54971e43 LP	174	* should be released after parsing and before resuming boot
54971e43 LP	175	*/
6b11d1d6	176	acpi_put_table(table);
54971e43	177	return ret;
37655163 AS	178	}
	179
	180	/*
	181	* acpi_boot_table_init() called from setup_arch(), always.
	182	* 1. find RSDP and get its address, and then find XSDT
	183	* 2. extract all tables and checksums them all
	184	* 3. check ACPI FADT revision
54971e43	185	* 4. check ACPI FADT HW reduced flag
37655163 AS	186	*
	187	* We can parse ACPI boot-time tables such as MADT after
	188	* this function is called.
54971e43	189	*
fb094eb1 LP	190	* On return ACPI is enabled if either:
	191	*
	192	* - ACPI tables are initialized and sanity checks passed
	193	* - acpi=force was passed in the command line and ACPI was not disabled
	194	* explicitly through acpi=off command line parameter
	195	*
	196	* ACPI is disabled on function return otherwise
37655163 AS	197	*/
	198	void __init acpi_boot_table_init(void)
	199	{
b10d79f7 AS	200	/*
	201	* Enable ACPI instead of device tree unless
	202	* - ACPI has been disabled explicitly (acpi=off), or
2366c7fd SZ	203	* - the device tree is not empty (it has more than just a /chosen node,
2366c7fd SZ	204	* and a /hypervisor node when running on Xen)
6a1f5471	205	* and ACPI has not been [force] enabled (acpi=on\|force)
b10d79f7 AS	206	*/
b10d79f7 AS	207	if (param_acpi_off \|\|
6a1f5471 AB	208	(!param_acpi_on && !param_acpi_force &&
6a1f5471 AB	209	of_scan_flat_dt(dt_scan_depth1_nodes, NULL)))
888125a7	210	goto done;
37655163	211
54971e43 LP	212	/*
	213	* ACPI is disabled at this point. Enable it in order to parse
	214	* the ACPI tables and carry out sanity checks
	215	*/
b10d79f7 AS	216	enable_acpi();
b10d79f7 AS	217
54971e43 LP	218	/*
	219	* If ACPI tables are initialized and FADT sanity checks passed,
	220	* leave ACPI enabled and carry on booting; otherwise disable ACPI
	221	* on initialization error.
fb094eb1 LP	222	* If acpi=force was passed on the command line it forces ACPI
fb094eb1 LP	223	* to be enabled even if its initialization failed.
54971e43 LP	224	*/
	225	if (acpi_table_init() \|\| acpi_fadt_sanity_check()) {
	226	pr_err("Failed to init ACPI tables\n");
fb094eb1 LP	227	if (!param_acpi_force)
fb094eb1 LP	228	disable_acpi();
37655163	229	}
888125a7 AM	230
	231	done:
	232	if (acpi_disabled) {
0231d000	233	if (earlycon_acpi_spcr_enable)
888125a7 AM	234	early_init_dt_scan_chosen_stdout();
888125a7 AM	235	} else {
0231d000	236	acpi_parse_spcr(earlycon_acpi_spcr_enable, true);
6e7300cf BS	237	if (IS_ENABLED(CONFIG_ACPI_BGRT))
6e7300cf BS	238	acpi_table_parse(ACPI_SIG_BGRT, acpi_parse_bgrt);
888125a7	239	}
37655163	240	}
d60fc389	241
09ffcb0d	242	pgprot_t __acpi_get_mem_attribute(phys_addr_t addr)
89e44b51 JZZ	243	{
	244	/*
	245	* According to "Table 8 Map: EFI memory types to AArch64 memory
	246	* types" of UEFI 2.5 section 2.3.6.1, each EFI memory type is
	247	* mapped to a corresponding MAIR attribute encoding.
	248	* The EFI memory attribute advises all possible capabilities
	249	* of a memory region. We use the most efficient capability.
	250	*/
	251
	252	u64 attr;
	253
	254	attr = efi_mem_attributes(addr);
	255	if (attr & EFI_MEMORY_WB)
	256	return PAGE_KERNEL;
	257	if (attr & EFI_MEMORY_WT)
	258	return __pgprot(PROT_NORMAL_WT);
	259	if (attr & EFI_MEMORY_WC)
	260	return __pgprot(PROT_NORMAL_NC);
	261	return __pgprot(PROT_DEVICE_nGnRnE);
	262	}
d44f1b8d	263
1583052d AB	264	void __iomem *acpi_os_ioremap(acpi_physical_address phys, acpi_size size)
	265	{
	266	efi_memory_desc_t md, region = NULL;
	267	pgprot_t prot;
	268
	269	if (WARN_ON_ONCE(!efi_enabled(EFI_MEMMAP)))
	270	return NULL;
	271
	272	for_each_efi_memory_desc(md) {
	273	u64 end = md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT);
	274
	275	if (phys < md->phys_addr \|\| phys >= end)
	276	continue;
	277
	278	if (phys + size > end) {
	279	pr_warn(FW_BUG "requested region covers multiple EFI memory regions\n");
	280	return NULL;
	281	}
	282	region = md;
	283	break;
	284	}
	285
	286	/*
	287	* It is fine for AML to remap regions that are not represented in the
	288	* EFI memory map at all, as it only describes normal memory, and MMIO
	289	* regions that require a virtual mapping to make them accessible to
	290	* the EFI runtime services.
	291	*/
	292	prot = __pgprot(PROT_DEVICE_nGnRnE);
	293	if (region) {
	294	switch (region->type) {
	295	case EFI_LOADER_CODE:
	296	case EFI_LOADER_DATA:
	297	case EFI_BOOT_SERVICES_CODE:
	298	case EFI_BOOT_SERVICES_DATA:
	299	case EFI_CONVENTIONAL_MEMORY:
	300	case EFI_PERSISTENT_MEMORY:
	301	pr_warn(FW_BUG "requested region covers kernel memory @ %pa\n", &phys);
	302	return NULL;
325f5585 AB	303
	304	case EFI_RUNTIME_SERVICES_CODE:
	305	/*
	306	* This would be unusual, but not problematic per se,
	307	* as long as we take care not to create a writable
	308	* mapping for executable code.
	309	*/
	310	prot = PAGE_KERNEL_RO;
	311	break;
1583052d AB	312
	313	case EFI_ACPI_RECLAIM_MEMORY:
	314	/*
	315	* ACPI reclaim memory is used to pass firmware tables
	316	* and other data that is intended for consumption by
	317	* the OS only, which may decide it wants to reclaim
	318	* that memory and use it for something else. We never
	319	* do that, but we usually add it to the linear map
	320	* anyway, in which case we should use the existing
	321	* mapping.
	322	*/
	323	if (memblock_is_map_memory(phys))
	324	return (void __iomem *)__phys_to_virt(phys);
df561f66	325	fallthrough;
1583052d AB	326
	327	default:
	328	if (region->attribute & EFI_MEMORY_WB)
	329	prot = PAGE_KERNEL;
	330	else if (region->attribute & EFI_MEMORY_WT)
	331	prot = __pgprot(PROT_NORMAL_WT);
	332	else if (region->attribute & EFI_MEMORY_WC)
	333	prot = __pgprot(PROT_NORMAL_NC);
	334	}
	335	}
	336	return __ioremap(phys, size, prot);
	337	}
	338
d44f1b8d JM	339	/*
	340	* Claim Synchronous External Aborts as a firmware first notification.
	341	*
	342	* Used by KVM and the arch do_sea handler.
	343	* @regs may be NULL when called from process context.
	344	*/
	345	int apei_claim_sea(struct pt_regs *regs)
	346	{
	347	int err = -ENOENT;
8fcc4ae6	348	bool return_to_irqs_enabled;
d44f1b8d JM	349	unsigned long current_flags;
	350
	351	if (!IS_ENABLED(CONFIG_ACPI_APEI_GHES))
	352	return err;
	353
e533dbe9	354	current_flags = local_daif_save_flags();
d44f1b8d	355
8fcc4ae6 JM	356	/* current_flags isn't useful here as daif doesn't tell us about pNMI */
	357	return_to_irqs_enabled = !irqs_disabled_flags(arch_local_save_flags());
	358
	359	if (regs)
	360	return_to_irqs_enabled = interrupts_enabled(regs);
	361
d44f1b8d JM	362	/*
	363	* SEA can interrupt SError, mask it and describe this as an NMI so
	364	* that APEI defers the handling.
	365	*/
	366	local_daif_restore(DAIF_ERRCTX);
	367	nmi_enter();
	368	err = ghes_notify_sea();
	369	nmi_exit();
8fcc4ae6 JM	370
	371	/*
	372	* APEI NMI-like notifications are deferred to irq_work. Unless
	373	* we interrupted irqs-masked code, we can do that now.
	374	*/
	375	if (!err) {
	376	if (return_to_irqs_enabled) {
	377	local_daif_restore(DAIF_PROCCTX_NOIRQ);
	378	__irq_enter();
	379	irq_work_run();
	380	__irq_exit();
	381	} else {
	382	pr_warn_ratelimited("APEI work queued but not completed");
	383	err = -EINPROGRESS;
	384	}
	385	}
	386
d44f1b8d JM	387	local_daif_restore(current_flags);
	388
	389	return err;
	390	}