1 files changed, 851 insertions, 0 deletions

diff --git a/drivers/acpi/apei/einj.c b/drivers/acpi/apei/einj.c
new file mode 100644
index 000000000..b38737c83
--- /dev/null
+++ b/drivers/acpi/apei/einj.c
@@ -0,0 +1,851 @@
+/*
+ * APEI Error INJection support
+ *
+ * EINJ provides a hardware error injection mechanism, this is useful
+ * for debugging and testing of other APEI and RAS features.
+ *
+ * For more information about EINJ, please refer to ACPI Specification
+ * version 4.0, section 17.5.
+ *
+ * Copyright 2009-2010 Intel Corp.
+ *   Author: Huang Ying <ying.huang@intel.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version
+ * 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
+#include <linux/nmi.h>
+#include <linux/delay.h>
+#include <linux/mm.h>
+#include <asm/unaligned.h>
+
+#include "apei-internal.h"
+
+#undef pr_fmt
+#define pr_fmt(fmt) "EINJ: " fmt
+
+#define SPIN_UNIT		100			/* 100ns */
+/* Firmware should respond within 1 milliseconds */
+#define FIRMWARE_TIMEOUT	(1 * NSEC_PER_MSEC)
+#define ACPI5_VENDOR_BIT	BIT(31)
+#define MEM_ERROR_MASK		(ACPI_EINJ_MEMORY_CORRECTABLE | \
+				ACPI_EINJ_MEMORY_UNCORRECTABLE | \
+				ACPI_EINJ_MEMORY_FATAL)
+
+/*
+ * ACPI version 5 provides a SET_ERROR_TYPE_WITH_ADDRESS action.
+ */
+static int acpi5;
+
+struct set_error_type_with_address {
+	u32	type;
+	u32	vendor_extension;
+	u32	flags;
+	u32	apicid;
+	u64	memory_address;
+	u64	memory_address_range;
+	u32	pcie_sbdf;
+};
+enum {
+	SETWA_FLAGS_APICID = 1,
+	SETWA_FLAGS_MEM = 2,
+	SETWA_FLAGS_PCIE_SBDF = 4,
+};
+
+/*
+ * Vendor extensions for platform specific operations
+ */
+struct vendor_error_type_extension {
+	u32	length;
+	u32	pcie_sbdf;
+	u16	vendor_id;
+	u16	device_id;
+	u8	rev_id;
+	u8	reserved[3];
+};
+
+static u32 notrigger;
+
+static u32 vendor_flags;
+static struct debugfs_blob_wrapper vendor_blob;
+static char vendor_dev[64];
+
+/*
+ * Some BIOSes allow parameters to the SET_ERROR_TYPE entries in the
+ * EINJ table through an unpublished extension. Use with caution as
+ * most will ignore the parameter and make their own choice of address
+ * for error injection.  This extension is used only if
+ * param_extension module parameter is specified.
+ */
+struct einj_parameter {
+	u64 type;
+	u64 reserved1;
+	u64 reserved2;
+	u64 param1;
+	u64 param2;
+};
+
+#define EINJ_OP_BUSY			0x1
+#define EINJ_STATUS_SUCCESS		0x0
+#define EINJ_STATUS_FAIL		0x1
+#define EINJ_STATUS_INVAL		0x2
+
+#define EINJ_TAB_ENTRY(tab)						\
+	((struct acpi_whea_header *)((char *)(tab) +			\
+				    sizeof(struct acpi_table_einj)))
+
+static bool param_extension;
+module_param(param_extension, bool, 0);
+
+static struct acpi_table_einj *einj_tab;
+
+static struct apei_resources einj_resources;
+
+static struct apei_exec_ins_type einj_ins_type[] = {
+	[ACPI_EINJ_READ_REGISTER] = {
+		.flags = APEI_EXEC_INS_ACCESS_REGISTER,
+		.run   = apei_exec_read_register,
+	},
+	[ACPI_EINJ_READ_REGISTER_VALUE] = {
+		.flags = APEI_EXEC_INS_ACCESS_REGISTER,
+		.run   = apei_exec_read_register_value,
+	},
+	[ACPI_EINJ_WRITE_REGISTER] = {
+		.flags = APEI_EXEC_INS_ACCESS_REGISTER,
+		.run   = apei_exec_write_register,
+	},
+	[ACPI_EINJ_WRITE_REGISTER_VALUE] = {
+		.flags = APEI_EXEC_INS_ACCESS_REGISTER,
+		.run   = apei_exec_write_register_value,
+	},
+	[ACPI_EINJ_NOOP] = {
+		.flags = 0,
+		.run   = apei_exec_noop,
+	},
+};
+
+/*
+ * Prevent EINJ interpreter to run simultaneously, because the
+ * corresponding firmware implementation may not work properly when
+ * invoked simultaneously.
+ */
+static DEFINE_MUTEX(einj_mutex);
+
+static void *einj_param;
+
+static void einj_exec_ctx_init(struct apei_exec_context *ctx)
+{
+	apei_exec_ctx_init(ctx, einj_ins_type, ARRAY_SIZE(einj_ins_type),
+			   EINJ_TAB_ENTRY(einj_tab), einj_tab->entries);
+}
+
+static int __einj_get_available_error_type(u32 *type)
+{
+	struct apei_exec_context ctx;
+	int rc;
+
+	einj_exec_ctx_init(&ctx);
+	rc = apei_exec_run(&ctx, ACPI_EINJ_GET_ERROR_TYPE);
+	if (rc)
+		return rc;
+	*type = apei_exec_ctx_get_output(&ctx);
+
+	return 0;
+}
+
+/* Get error injection capabilities of the platform */
+static int einj_get_available_error_type(u32 *type)
+{
+	int rc;
+
+	mutex_lock(&einj_mutex);
+	rc = __einj_get_available_error_type(type);
+	mutex_unlock(&einj_mutex);
+
+	return rc;
+}
+
+static int einj_timedout(u64 *t)
+{
+	if ((s64)*t < SPIN_UNIT) {
+		pr_warning(FW_WARN "Firmware does not respond in time\n");
+		return 1;
+	}
+	*t -= SPIN_UNIT;
+	ndelay(SPIN_UNIT);
+	touch_nmi_watchdog();
+	return 0;
+}
+
+static void check_vendor_extension(u64 paddr,
+				   struct set_error_type_with_address *v5param)
+{
+	int	offset = v5param->vendor_extension;
+	struct	vendor_error_type_extension *v;
+	u32	sbdf;
+
+	if (!offset)
+		return;
+	v = acpi_os_map_iomem(paddr + offset, sizeof(*v));
+	if (!v)
+		return;
+	sbdf = v->pcie_sbdf;
+	sprintf(vendor_dev, "%x:%x:%x.%x vendor_id=%x device_id=%x rev_id=%x\n",
+		sbdf >> 24, (sbdf >> 16) & 0xff,
+		(sbdf >> 11) & 0x1f, (sbdf >> 8) & 0x7,
+		 v->vendor_id, v->device_id, v->rev_id);
+	acpi_os_unmap_iomem(v, sizeof(*v));
+}
+
+static void *einj_get_parameter_address(void)
+{
+	int i;
+	u64 pa_v4 = 0, pa_v5 = 0;
+	struct acpi_whea_header *entry;
+
+	entry = EINJ_TAB_ENTRY(einj_tab);
+	for (i = 0; i < einj_tab->entries; i++) {
+		if (entry->action == ACPI_EINJ_SET_ERROR_TYPE &&
+		    entry->instruction == ACPI_EINJ_WRITE_REGISTER &&
+		    entry->register_region.space_id ==
+		    ACPI_ADR_SPACE_SYSTEM_MEMORY)
+			pa_v4 = get_unaligned(&entry->register_region.address);
+		if (entry->action == ACPI_EINJ_SET_ERROR_TYPE_WITH_ADDRESS &&
+		    entry->instruction == ACPI_EINJ_WRITE_REGISTER &&
+		    entry->register_region.space_id ==
+		    ACPI_ADR_SPACE_SYSTEM_MEMORY)
+			pa_v5 = get_unaligned(&entry->register_region.address);
+		entry++;
+	}
+	if (pa_v5) {
+		struct set_error_type_with_address *v5param;
+
+		v5param = acpi_os_map_iomem(pa_v5, sizeof(*v5param));
+		if (v5param) {
+			acpi5 = 1;
+			check_vendor_extension(pa_v5, v5param);
+			return v5param;
+		}
+	}
+	if (param_extension && pa_v4) {
+		struct einj_parameter *v4param;
+
+		v4param = acpi_os_map_iomem(pa_v4, sizeof(*v4param));
+		if (!v4param)
+			return NULL;
+		if (v4param->reserved1 || v4param->reserved2) {
+			acpi_os_unmap_iomem(v4param, sizeof(*v4param));
+			return NULL;
+		}
+		return v4param;
+	}
+
+	return NULL;
+}
+
+/* do sanity check to trigger table */
+static int einj_check_trigger_header(struct acpi_einj_trigger *trigger_tab)
+{
+	if (trigger_tab->header_size != sizeof(struct acpi_einj_trigger))
+		return -EINVAL;
+	if (trigger_tab->table_size > PAGE_SIZE ||
+	    trigger_tab->table_size < trigger_tab->header_size)
+		return -EINVAL;
+	if (trigger_tab->entry_count !=
+	    (trigger_tab->table_size - trigger_tab->header_size) /
+	    sizeof(struct acpi_einj_entry))
+		return -EINVAL;
+
+	return 0;
+}
+
+static struct acpi_generic_address *einj_get_trigger_parameter_region(
+	struct acpi_einj_trigger *trigger_tab, u64 param1, u64 param2)
+{
+	int i;
+	struct acpi_whea_header *entry;
+
+	entry = (struct acpi_whea_header *)
+		((char *)trigger_tab + sizeof(struct acpi_einj_trigger));
+	for (i = 0; i < trigger_tab->entry_count; i++) {
+		if (entry->action == ACPI_EINJ_TRIGGER_ERROR &&
+		entry->instruction <= ACPI_EINJ_WRITE_REGISTER_VALUE &&
+		entry->register_region.space_id ==
+			ACPI_ADR_SPACE_SYSTEM_MEMORY &&
+		(entry->register_region.address & param2) == (param1 & param2))
+			return &entry->register_region;
+		entry++;
+	}
+
+	return NULL;
+}
+/* Execute instructions in trigger error action table */
+static int __einj_error_trigger(u64 trigger_paddr, u32 type,
+				u64 param1, u64 param2)
+{
+	struct acpi_einj_trigger *trigger_tab = NULL;
+	struct apei_exec_context trigger_ctx;
+	struct apei_resources trigger_resources;
+	struct acpi_whea_header *trigger_entry;
+	struct resource *r;
+	u32 table_size;
+	int rc = -EIO;
+	struct acpi_generic_address *trigger_param_region = NULL;
+
+	r = request_mem_region(trigger_paddr, sizeof(*trigger_tab),
+			       "APEI EINJ Trigger Table");
+	if (!r) {
+		pr_err("Can not request [mem %#010llx-%#010llx] for Trigger table\n",
+		       (unsigned long long)trigger_paddr,
+		       (unsigned long long)trigger_paddr +
+			    sizeof(*trigger_tab) - 1);
+		goto out;
+	}
+	trigger_tab = ioremap_cache(trigger_paddr, sizeof(*trigger_tab));
+	if (!trigger_tab) {
+		pr_err("Failed to map trigger table!\n");
+		goto out_rel_header;
+	}
+	rc = einj_check_trigger_header(trigger_tab);
+	if (rc) {
+		pr_warning(FW_BUG "Invalid trigger error action table.\n");
+		goto out_rel_header;
+	}
+
+	/* No action structures in the TRIGGER_ERROR table, nothing to do */
+	if (!trigger_tab->entry_count)
+		goto out_rel_header;
+
+	rc = -EIO;
+	table_size = trigger_tab->table_size;
+	r = request_mem_region(trigger_paddr + sizeof(*trigger_tab),
+			       table_size - sizeof(*trigger_tab),
+			       "APEI EINJ Trigger Table");
+	if (!r) {
+		pr_err("Can not request [mem %#010llx-%#010llx] for Trigger Table Entry\n",
+		       (unsigned long long)trigger_paddr + sizeof(*trigger_tab),
+		       (unsigned long long)trigger_paddr + table_size - 1);
+		goto out_rel_header;
+	}
+	iounmap(trigger_tab);
+	trigger_tab = ioremap_cache(trigger_paddr, table_size);
+	if (!trigger_tab) {
+		pr_err("Failed to map trigger table!\n");
+		goto out_rel_entry;
+	}
+	trigger_entry = (struct acpi_whea_header *)
+		((char *)trigger_tab + sizeof(struct acpi_einj_trigger));
+	apei_resources_init(&trigger_resources);
+	apei_exec_ctx_init(&trigger_ctx, einj_ins_type,
+			   ARRAY_SIZE(einj_ins_type),
+			   trigger_entry, trigger_tab->entry_count);
+	rc = apei_exec_collect_resources(&trigger_ctx, &trigger_resources);
+	if (rc)
+		goto out_fini;
+	rc = apei_resources_sub(&trigger_resources, &einj_resources);
+	if (rc)
+		goto out_fini;
+	/*
+	 * Some firmware will access target address specified in
+	 * param1 to trigger the error when injecting memory error.
+	 * This will cause resource conflict with regular memory.  So
+	 * remove it from trigger table resources.
+	 */
+	if ((param_extension || acpi5) && (type & MEM_ERROR_MASK) && param2) {
+		struct apei_resources addr_resources;
+		apei_resources_init(&addr_resources);
+		trigger_param_region = einj_get_trigger_parameter_region(
+			trigger_tab, param1, param2);
+		if (trigger_param_region) {
+			rc = apei_resources_add(&addr_resources,
+				trigger_param_region->address,
+				trigger_param_region->bit_width/8, true);
+			if (rc)
+				goto out_fini;
+			rc = apei_resources_sub(&trigger_resources,
+					&addr_resources);
+		}
+		apei_resources_fini(&addr_resources);
+		if (rc)
+			goto out_fini;
+	}
+	rc = apei_resources_request(&trigger_resources, "APEI EINJ Trigger");
+	if (rc)
+		goto out_fini;
+	rc = apei_exec_pre_map_gars(&trigger_ctx);
+	if (rc)
+		goto out_release;
+
+	rc = apei_exec_run(&trigger_ctx, ACPI_EINJ_TRIGGER_ERROR);
+
+	apei_exec_post_unmap_gars(&trigger_ctx);
+out_release:
+	apei_resources_release(&trigger_resources);
+out_fini:
+	apei_resources_fini(&trigger_resources);
+out_rel_entry:
+	release_mem_region(trigger_paddr + sizeof(*trigger_tab),
+			   table_size - sizeof(*trigger_tab));
+out_rel_header:
+	release_mem_region(trigger_paddr, sizeof(*trigger_tab));
+out:
+	if (trigger_tab)
+		iounmap(trigger_tab);
+
+	return rc;
+}
+
+static int __einj_error_inject(u32 type, u32 flags, u64 param1, u64 param2,
+			       u64 param3, u64 param4)
+{
+	struct apei_exec_context ctx;
+	u64 val, trigger_paddr, timeout = FIRMWARE_TIMEOUT;
+	int rc;
+
+	einj_exec_ctx_init(&ctx);
+
+	rc = apei_exec_run_optional(&ctx, ACPI_EINJ_BEGIN_OPERATION);
+	if (rc)
+		return rc;
+	apei_exec_ctx_set_input(&ctx, type);
+	if (acpi5) {
+		struct set_error_type_with_address *v5param = einj_param;
+
+		v5param->type = type;
+		if (type & ACPI5_VENDOR_BIT) {
+			switch (vendor_flags) {
+			case SETWA_FLAGS_APICID:
+				v5param->apicid = param1;
+				break;
+			case SETWA_FLAGS_MEM:
+				v5param->memory_address = param1;
+				v5param->memory_address_range = param2;
+				break;
+			case SETWA_FLAGS_PCIE_SBDF:
+				v5param->pcie_sbdf = param1;
+				break;
+			}
+			v5param->flags = vendor_flags;
+		} else if (flags) {
+				v5param->flags = flags;
+				v5param->memory_address = param1;
+				v5param->memory_address_range = param2;
+				v5param->apicid = param3;
+				v5param->pcie_sbdf = param4;
+		} else {
+			switch (type) {
+			case ACPI_EINJ_PROCESSOR_CORRECTABLE:
+			case ACPI_EINJ_PROCESSOR_UNCORRECTABLE:
+			case ACPI_EINJ_PROCESSOR_FATAL:
+				v5param->apicid = param1;
+				v5param->flags = SETWA_FLAGS_APICID;
+				break;
+			case ACPI_EINJ_MEMORY_CORRECTABLE:
+			case ACPI_EINJ_MEMORY_UNCORRECTABLE:
+			case ACPI_EINJ_MEMORY_FATAL:
+				v5param->memory_address = param1;
+				v5param->memory_address_range = param2;
+				v5param->flags = SETWA_FLAGS_MEM;
+				break;
+			case ACPI_EINJ_PCIX_CORRECTABLE:
+			case ACPI_EINJ_PCIX_UNCORRECTABLE:
+			case ACPI_EINJ_PCIX_FATAL:
+				v5param->pcie_sbdf = param1;
+				v5param->flags = SETWA_FLAGS_PCIE_SBDF;
+				break;
+			}
+		}
+	} else {
+		rc = apei_exec_run(&ctx, ACPI_EINJ_SET_ERROR_TYPE);
+		if (rc)
+			return rc;
+		if (einj_param) {
+			struct einj_parameter *v4param = einj_param;
+			v4param->param1 = param1;
+			v4param->param2 = param2;
+		}
+	}
+	rc = apei_exec_run(&ctx, ACPI_EINJ_EXECUTE_OPERATION);
+	if (rc)
+		return rc;
+	for (;;) {
+		rc = apei_exec_run(&ctx, ACPI_EINJ_CHECK_BUSY_STATUS);
+		if (rc)
+			return rc;
+		val = apei_exec_ctx_get_output(&ctx);
+		if (!(val & EINJ_OP_BUSY))
+			break;
+		if (einj_timedout(&timeout))
+			return -EIO;
+	}
+	rc = apei_exec_run(&ctx, ACPI_EINJ_GET_COMMAND_STATUS);
+	if (rc)
+		return rc;
+	val = apei_exec_ctx_get_output(&ctx);
+	if (val != EINJ_STATUS_SUCCESS)
+		return -EBUSY;
+
+	rc = apei_exec_run(&ctx, ACPI_EINJ_GET_TRIGGER_TABLE);
+	if (rc)
+		return rc;
+	trigger_paddr = apei_exec_ctx_get_output(&ctx);
+	if (notrigger == 0) {
+		rc = __einj_error_trigger(trigger_paddr, type, param1, param2);
+		if (rc)
+			return rc;
+	}
+	rc = apei_exec_run_optional(&ctx, ACPI_EINJ_END_OPERATION);
+
+	return rc;
+}
+
+/* Inject the specified hardware error */
+static int einj_error_inject(u32 type, u32 flags, u64 param1, u64 param2,
+			     u64 param3, u64 param4)
+{
+	int rc;
+	u64 base_addr, size;
+
+	/* If user manually set "flags", make sure it is legal */
+	if (flags && (flags &
+		~(SETWA_FLAGS_APICID|SETWA_FLAGS_MEM|SETWA_FLAGS_PCIE_SBDF)))
+		return -EINVAL;
+
+	/*
+	 * We need extra sanity checks for memory errors.
+	 * Other types leap directly to injection.
+	 */
+
+	/* ensure param1/param2 existed */
+	if (!(param_extension || acpi5))
+		goto inject;
+
+	/* ensure injection is memory related */
+	if (type & ACPI5_VENDOR_BIT) {
+		if (vendor_flags != SETWA_FLAGS_MEM)
+			goto inject;
+	} else if (!(type & MEM_ERROR_MASK) && !(flags & SETWA_FLAGS_MEM))
+		goto inject;
+
+	/*
+	 * Disallow crazy address masks that give BIOS leeway to pick
+	 * injection address almost anywhere. Insist on page or
+	 * better granularity and that target address is normal RAM or
+	 * NVDIMM.
+	 */
+	base_addr = param1 & param2;
+	size = ~param2 + 1;
+
+	if (((param2 & PAGE_MASK) != PAGE_MASK) ||
+	    ((region_intersects(base_addr, size, IORESOURCE_SYSTEM_RAM, IORES_DESC_NONE)
+				!= REGION_INTERSECTS) &&
+	     (region_intersects(base_addr, size, IORESOURCE_MEM, IORES_DESC_PERSISTENT_MEMORY)
+				!= REGION_INTERSECTS)))
+		return -EINVAL;
+
+inject:
+	mutex_lock(&einj_mutex);
+	rc = __einj_error_inject(type, flags, param1, param2, param3, param4);
+	mutex_unlock(&einj_mutex);
+
+	return rc;
+}
+
+static u32 error_type;
+static u32 error_flags;
+static u64 error_param1;
+static u64 error_param2;
+static u64 error_param3;
+static u64 error_param4;
+static struct dentry *einj_debug_dir;
+
+static int available_error_type_show(struct seq_file *m, void *v)
+{
+	int rc;
+	u32 available_error_type = 0;
+
+	rc = einj_get_available_error_type(&available_error_type);
+	if (rc)
+		return rc;
+	if (available_error_type & 0x0001)
+		seq_printf(m, "0x00000001\tProcessor Correctable\n");
+	if (available_error_type & 0x0002)
+		seq_printf(m, "0x00000002\tProcessor Uncorrectable non-fatal\n");
+	if (available_error_type & 0x0004)
+		seq_printf(m, "0x00000004\tProcessor Uncorrectable fatal\n");
+	if (available_error_type & 0x0008)
+		seq_printf(m, "0x00000008\tMemory Correctable\n");
+	if (available_error_type & 0x0010)
+		seq_printf(m, "0x00000010\tMemory Uncorrectable non-fatal\n");
+	if (available_error_type & 0x0020)
+		seq_printf(m, "0x00000020\tMemory Uncorrectable fatal\n");
+	if (available_error_type & 0x0040)
+		seq_printf(m, "0x00000040\tPCI Express Correctable\n");
+	if (available_error_type & 0x0080)
+		seq_printf(m, "0x00000080\tPCI Express Uncorrectable non-fatal\n");
+	if (available_error_type & 0x0100)
+		seq_printf(m, "0x00000100\tPCI Express Uncorrectable fatal\n");
+	if (available_error_type & 0x0200)
+		seq_printf(m, "0x00000200\tPlatform Correctable\n");
+	if (available_error_type & 0x0400)
+		seq_printf(m, "0x00000400\tPlatform Uncorrectable non-fatal\n");
+	if (available_error_type & 0x0800)
+		seq_printf(m, "0x00000800\tPlatform Uncorrectable fatal\n");
+
+	return 0;
+}
+
+static int available_error_type_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, available_error_type_show, NULL);
+}
+
+static const struct file_operations available_error_type_fops = {
+	.open		= available_error_type_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+
+static int error_type_get(void *data, u64 *val)
+{
+	*val = error_type;
+
+	return 0;
+}
+
+static int error_type_set(void *data, u64 val)
+{
+	int rc;
+	u32 available_error_type = 0;
+	u32 tval, vendor;
+
+	/*
+	 * Vendor defined types have 0x80000000 bit set, and
+	 * are not enumerated by ACPI_EINJ_GET_ERROR_TYPE
+	 */
+	vendor = val & ACPI5_VENDOR_BIT;
+	tval = val & 0x7fffffff;
+
+	/* Only one error type can be specified */
+	if (tval & (tval - 1))
+		return -EINVAL;
+	if (!vendor) {
+		rc = einj_get_available_error_type(&available_error_type);
+		if (rc)
+			return rc;
+		if (!(val & available_error_type))
+			return -EINVAL;
+	}
+	error_type = val;
+
+	return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(error_type_fops, error_type_get,
+			error_type_set, "0x%llx\n");
+
+static int error_inject_set(void *data, u64 val)
+{
+	if (!error_type)
+		return -EINVAL;
+
+	return einj_error_inject(error_type, error_flags, error_param1, error_param2,
+		error_param3, error_param4);
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(error_inject_fops, NULL,
+			error_inject_set, "%llu\n");
+
+static int einj_check_table(struct acpi_table_einj *einj_tab)
+{
+	if ((einj_tab->header_length !=
+	     (sizeof(struct acpi_table_einj) - sizeof(einj_tab->header)))
+	    && (einj_tab->header_length != sizeof(struct acpi_table_einj)))
+		return -EINVAL;
+	if (einj_tab->header.length < sizeof(struct acpi_table_einj))
+		return -EINVAL;
+	if (einj_tab->entries !=
+	    (einj_tab->header.length - sizeof(struct acpi_table_einj)) /
+	    sizeof(struct acpi_einj_entry))
+		return -EINVAL;
+
+	return 0;
+}
+
+static int __init einj_init(void)
+{
+	int rc;
+	acpi_status status;
+	struct dentry *fentry;
+	struct apei_exec_context ctx;
+
+	if (acpi_disabled) {
+		pr_warn("ACPI disabled.\n");
+		return -ENODEV;
+	}
+
+	status = acpi_get_table(ACPI_SIG_EINJ, 0,
+				(struct acpi_table_header **)&einj_tab);
+	if (status == AE_NOT_FOUND) {
+		pr_warn("EINJ table not found.\n");
+		return -ENODEV;
+	}
+	else if (ACPI_FAILURE(status)) {
+		pr_err("Failed to get EINJ table: %s\n",
+				acpi_format_exception(status));
+		return -EINVAL;
+	}
+
+	rc = einj_check_table(einj_tab);
+	if (rc) {
+		pr_warn(FW_BUG "Invalid EINJ table.\n");
+		return -EINVAL;
+	}
+
+	rc = -ENOMEM;
+	einj_debug_dir = debugfs_create_dir("einj", apei_get_debugfs_dir());
+	if (!einj_debug_dir) {
+		pr_err("Error creating debugfs node.\n");
+		goto err_cleanup;
+	}
+
+	fentry = debugfs_create_file("available_error_type", S_IRUSR,
+				     einj_debug_dir, NULL,
+				     &available_error_type_fops);
+	if (!fentry)
+		goto err_cleanup;
+
+	fentry = debugfs_create_file("error_type", S_IRUSR | S_IWUSR,
+				     einj_debug_dir, NULL, &error_type_fops);
+	if (!fentry)
+		goto err_cleanup;
+	fentry = debugfs_create_file("error_inject", S_IWUSR,
+				     einj_debug_dir, NULL, &error_inject_fops);
+	if (!fentry)
+		goto err_cleanup;
+
+	apei_resources_init(&einj_resources);
+	einj_exec_ctx_init(&ctx);
+	rc = apei_exec_collect_resources(&ctx, &einj_resources);
+	if (rc) {
+		pr_err("Error collecting EINJ resources.\n");
+		goto err_fini;
+	}
+
+	rc = apei_resources_request(&einj_resources, "APEI EINJ");
+	if (rc) {
+		pr_err("Error requesting memory/port resources.\n");
+		goto err_fini;
+	}
+
+	rc = apei_exec_pre_map_gars(&ctx);
+	if (rc) {
+		pr_err("Error pre-mapping GARs.\n");
+		goto err_release;
+	}
+
+	rc = -ENOMEM;
+	einj_param = einj_get_parameter_address();
+	if ((param_extension || acpi5) && einj_param) {
+		fentry = debugfs_create_x32("flags", S_IRUSR | S_IWUSR,
+					    einj_debug_dir, &error_flags);
+		if (!fentry)
+			goto err_unmap;
+		fentry = debugfs_create_x64("param1", S_IRUSR | S_IWUSR,
+					    einj_debug_dir, &error_param1);
+		if (!fentry)
+			goto err_unmap;
+		fentry = debugfs_create_x64("param2", S_IRUSR | S_IWUSR,
+					    einj_debug_dir, &error_param2);
+		if (!fentry)
+			goto err_unmap;
+		fentry = debugfs_create_x64("param3", S_IRUSR | S_IWUSR,
+					    einj_debug_dir, &error_param3);
+		if (!fentry)
+			goto err_unmap;
+		fentry = debugfs_create_x64("param4", S_IRUSR | S_IWUSR,
+					    einj_debug_dir, &error_param4);
+		if (!fentry)
+			goto err_unmap;
+
+		fentry = debugfs_create_x32("notrigger", S_IRUSR | S_IWUSR,
+					    einj_debug_dir, &notrigger);
+		if (!fentry)
+			goto err_unmap;
+	}
+
+	if (vendor_dev[0]) {
+		vendor_blob.data = vendor_dev;
+		vendor_blob.size = strlen(vendor_dev);
+		fentry = debugfs_create_blob("vendor", S_IRUSR,
+					     einj_debug_dir, &vendor_blob);
+		if (!fentry)
+			goto err_unmap;
+		fentry = debugfs_create_x32("vendor_flags", S_IRUSR | S_IWUSR,
+					    einj_debug_dir, &vendor_flags);
+		if (!fentry)
+			goto err_unmap;
+	}
+
+	pr_info("Error INJection is initialized.\n");
+
+	return 0;
+
+err_unmap:
+	if (einj_param) {
+		acpi_size size = (acpi5) ?
+			sizeof(struct set_error_type_with_address) :
+			sizeof(struct einj_parameter);
+
+		acpi_os_unmap_iomem(einj_param, size);
+		pr_err("Error creating param extension debugfs nodes.\n");
+	}
+	apei_exec_post_unmap_gars(&ctx);
+err_release:
+	apei_resources_release(&einj_resources);
+err_fini:
+	apei_resources_fini(&einj_resources);
+err_cleanup:
+	pr_err("Error creating primary debugfs nodes.\n");
+	debugfs_remove_recursive(einj_debug_dir);
+
+	return rc;
+}
+
+static void __exit einj_exit(void)
+{
+	struct apei_exec_context ctx;
+
+	if (einj_param) {
+		acpi_size size = (acpi5) ?
+			sizeof(struct set_error_type_with_address) :
+			sizeof(struct einj_parameter);
+
+		acpi_os_unmap_iomem(einj_param, size);
+	}
+	einj_exec_ctx_init(&ctx);
+	apei_exec_post_unmap_gars(&ctx);
+	apei_resources_release(&einj_resources);
+	apei_resources_fini(&einj_resources);
+	debugfs_remove_recursive(einj_debug_dir);
+}
+
+module_init(einj_init);
+module_exit(einj_exit);
+
+MODULE_AUTHOR("Huang Ying");
+MODULE_DESCRIPTION("APEI Error INJection support");
+MODULE_LICENSE("GPL");