// SPDX-License-Identifier: GPL-2.0-only
/*
 * 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>
 */

#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 <linux/device/faux.h>
#include <linux/unaligned.h>

#include "apei-internal.h"

#undef pr_fmt
#define pr_fmt(fmt) "EINJ: " fmt

#define SLEEP_UNIT_MIN          1000                    /* 1ms */
#define SLEEP_UNIT_MAX          5000                    /* 5ms */
/* Firmware should respond within 1 seconds */
#define FIRMWARE_TIMEOUT        (1 * USEC_PER_SEC)
#define COMPONENT_LEN           16
#define ACPI65_EINJV2_SUPP      BIT(30)
#define ACPI5_VENDOR_BIT        BIT(31)
#define MEM_ERROR_MASK          (ACPI_EINJ_MEMORY_CORRECTABLE | \
                                ACPI_EINJ_MEMORY_UNCORRECTABLE | \
                                ACPI_EINJ_MEMORY_FATAL)
#define CXL_ERROR_MASK          (ACPI_EINJ_CXL_CACHE_CORRECTABLE | \
                                ACPI_EINJ_CXL_CACHE_UNCORRECTABLE | \
                                ACPI_EINJ_CXL_CACHE_FATAL | \
                                ACPI_EINJ_CXL_MEM_CORRECTABLE | \
                                ACPI_EINJ_CXL_MEM_UNCORRECTABLE | \
                                ACPI_EINJ_CXL_MEM_FATAL)

/*
 * ACPI version 5 provides a SET_ERROR_TYPE_WITH_ADDRESS action.
 */
static int acpi5;

struct syndrome_array {
        union {
                u8      acpi_id[COMPONENT_LEN];
                u8      device_id[COMPONENT_LEN];
                u8      pcie_sbdf[COMPONENT_LEN];
                u8      vendor_id[COMPONENT_LEN];
        } comp_id;
        union {
                u8      proc_synd[COMPONENT_LEN];
                u8      mem_synd[COMPONENT_LEN];
                u8      pcie_synd[COMPONENT_LEN];
                u8      vendor_synd[COMPONENT_LEN];
        } comp_synd;
};

struct einjv2_extension_struct {
        u32 length;
        u16 revision;
        u16 component_arr_count;
        struct syndrome_array component_arr[] __counted_by(component_arr_count);
};

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;
        struct  einjv2_extension_struct einjv2_struct;
};
enum {
        SETWA_FLAGS_APICID = 1,
        SETWA_FLAGS_MEM = 2,
        SETWA_FLAGS_PCIE_SBDF = 4,
        SETWA_FLAGS_EINJV2 = 8,
};

/*
 * 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 struct debugfs_blob_wrapper vendor_errors;
static char vendor_dev[64];

static u32 max_nr_components;
static u32 available_error_type;
static u32 available_error_type_v2;
static struct syndrome_array *syndrome_data;

/*
 * 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);

/*
 * Exported APIs use this flag to exit early if einj_probe() failed.
 */
bool einj_initialized __ro_after_init;

static void __iomem *einj_param;
static u32 v5param_size;
static u32 v66param_size;
static bool is_v2;

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, int einj_action)
{
        struct apei_exec_context ctx;
        int rc;

        einj_exec_ctx_init(&ctx);
        rc = apei_exec_run(&ctx, einj_action);
        if (rc)
                return rc;
        *type = apei_exec_ctx_get_output(&ctx);

        return 0;
}

/* Get error injection capabilities of the platform */
int einj_get_available_error_type(u32 *type, int einj_action)
{
        int rc;

        mutex_lock(&einj_mutex);
        rc = __einj_get_available_error_type(type, einj_action);
        mutex_unlock(&einj_mutex);

        return rc;
}

static int einj_get_available_error_types(u32 *type1, u32 *type2)
{
        int rc;

        rc = einj_get_available_error_type(type1, ACPI_EINJ_GET_ERROR_TYPE);
        if (rc)
                return rc;
        if (*type1 & ACPI65_EINJV2_SUPP) {
                rc = einj_get_available_error_type(type2,
                                                   ACPI_EINJV2_GET_ERROR_TYPE);
                if (rc)
                        return rc;
        }

        return 0;
}

static int einj_timedout(u64 *t)
{
        if ((s64)*t < SLEEP_UNIT_MIN) {
                pr_warn(FW_WARN "Firmware does not respond in time\n");
                return 1;
        }
        *t -= SLEEP_UNIT_MIN;
        usleep_range(SLEEP_UNIT_MIN, SLEEP_UNIT_MAX);

        return 0;
}

static void get_oem_vendor_struct(u64 paddr, int offset,
                                  struct vendor_error_type_extension *v)
{
        unsigned long vendor_size;
        u64 target_pa = paddr + offset + sizeof(struct vendor_error_type_extension);

        vendor_size = v->length - sizeof(struct vendor_error_type_extension);

        if (vendor_size)
                vendor_errors.data = acpi_os_map_memory(target_pa, vendor_size);

        if (vendor_errors.data)
                vendor_errors.size = vendor_size;
}

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;
        struct vendor_error_type_extension __iomem *p;
        u32     sbdf;

        if (!offset)
                return;
        p = acpi_os_map_iomem(paddr + offset, sizeof(*p));
        if (!p)
                return;
        memcpy_fromio(&v, p, sizeof(v));
        get_oem_vendor_struct(paddr, offset, &v);
        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(p, sizeof(v));
}

static u32 einjv2_init(struct einjv2_extension_struct *e)
{
        if (e->revision != 1) {
                pr_info("Unknown v2 extension revision %u\n", e->revision);
                return 0;
        }
        if (e->length < sizeof(*e) || e->length > PAGE_SIZE) {
                pr_info(FW_BUG "Bad1 v2 extension length %u\n", e->length);
                return 0;
        }
        if ((e->length - sizeof(*e)) % sizeof(e->component_arr[0])) {
                pr_info(FW_BUG "Bad2 v2 extension length %u\n", e->length);
                return 0;
        }

        return (e->length - sizeof(*e)) / sizeof(e->component_arr[0]);
}

static void __iomem *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;
                struct set_error_type_with_address __iomem *p;

                v5param_size = sizeof(v5param);
                p = acpi_os_map_iomem(pa_v5, sizeof(*p));
                if (p) {
                        memcpy_fromio(&v5param, p, v5param_size);
                        acpi5 = 1;
                        check_vendor_extension(pa_v5, &v5param);
                        if (available_error_type & ACPI65_EINJV2_SUPP) {
                                struct einjv2_extension_struct *e;

                                e = &v5param.einjv2_struct;
                                max_nr_components = einjv2_init(e);

                                /* remap including einjv2_extension_struct */
                                acpi_os_unmap_iomem(p, v5param_size);
                                v66param_size = v5param_size - sizeof(*e) + e->length;
                                p = acpi_os_map_iomem(pa_v5, v66param_size);
                        }

                        return p;
                }
        }
        if (param_extension && pa_v4) {
                struct einj_parameter v4param;
                struct einj_parameter __iomem *p;

                p = acpi_os_map_iomem(pa_v4, sizeof(*p));
                if (!p)
                        return NULL;
                memcpy_fromio(&v4param, p, sizeof(v4param));
                if (v4param.reserved1 || v4param.reserved2) {
                        acpi_os_unmap_iomem(p, sizeof(v4param));
                        return NULL;
                }
                return p;
        }

        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;
}

static bool is_memory_injection(u32 type, u32 flags)
{
        if (flags & SETWA_FLAGS_EINJV2)
                return !!(type & ACPI_EINJV2_MEMORY);
        if (type & ACPI5_VENDOR_BIT)
                return !!(vendor_flags & SETWA_FLAGS_MEM);
        return !!(type & MEM_ERROR_MASK) || !!(flags & SETWA_FLAGS_MEM);
}

/* Execute instructions in trigger error action table */
static int __einj_error_trigger(u64 trigger_paddr, u32 type, u32 flags,
                                u64 param1, u64 param2)
{
        struct acpi_einj_trigger trigger_tab;
        struct acpi_einj_trigger *full_trigger_tab;
        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;
        struct acpi_einj_trigger __iomem *p = 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;
        }
        p = ioremap_cache(trigger_paddr, sizeof(*p));
        if (!p) {
                pr_err("Failed to map trigger table!\n");
                goto out_rel_header;
        }
        memcpy_fromio(&trigger_tab, p, sizeof(trigger_tab));
        rc = einj_check_trigger_header(&trigger_tab);
        if (rc) {
                pr_warn(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;
        full_trigger_tab = kmalloc(table_size, GFP_KERNEL);
        if (!full_trigger_tab)
                goto out_rel_header;
        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_free_trigger_tab;
        }
        iounmap(p);
        p = ioremap_cache(trigger_paddr, table_size);
        if (!p) {
                pr_err("Failed to map trigger table!\n");
                goto out_rel_entry;
        }
        memcpy_fromio(full_trigger_tab, p, table_size);
        trigger_entry = (struct acpi_whea_header *)
                ((char *)full_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) && is_memory_injection(type, flags)) {
                struct apei_resources addr_resources;

                apei_resources_init(&addr_resources);
                trigger_param_region = einj_get_trigger_parameter_region(
                        full_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_free_trigger_tab:
        kfree(full_trigger_tab);
out_rel_header:
        release_mem_region(trigger_paddr, sizeof(trigger_tab));
out:
        if (p)
                iounmap(p);

        return rc;
}

static bool is_end_of_list(u8 *val)
{
        for (int i = 0; i < COMPONENT_LEN; ++i) {
                if (val[i] != 0xFF)
                        return false;
        }
        return true;
}
static int __einj_error_inject(u32 type, u32 flags, u64 param1, u64 param2,
                               u64 param3, u64 param4)
{
        struct apei_exec_context ctx;
        u32 param_size = is_v2 ? v66param_size : v5param_size;
        u64 val, trigger_paddr, timeout = FIRMWARE_TIMEOUT;
        int i, 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;

                v5param = kmalloc(param_size, GFP_KERNEL);
                if (!v5param)
                        return -ENOMEM;

                memcpy_fromio(v5param, einj_param, param_size);
                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;

                        if (is_v2) {
                                for (i = 0; i < max_nr_components; i++) {
                                        if (is_end_of_list(syndrome_data[i].comp_id.acpi_id))
                                                break;
                                        v5param->einjv2_struct.component_arr[i].comp_id =
                                                syndrome_data[i].comp_id;
                                        v5param->einjv2_struct.component_arr[i].comp_synd =
                                                syndrome_data[i].comp_synd;
                                }
                                v5param->einjv2_struct.component_arr_count = i;
                        } else {
                                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;
                        }
                }
                memcpy_toio(einj_param, v5param, param_size);
                kfree(v5param);
        } else {
                rc = apei_exec_run(&ctx, ACPI_EINJ_SET_ERROR_TYPE);
                if (rc)
                        return rc;
                if (einj_param) {
                        struct einj_parameter v4param;

                        memcpy_fromio(&v4param, einj_param, sizeof(v4param));
                        v4param.param1 = param1;
                        v4param.param2 = param2;
                        memcpy_toio(einj_param, &v4param, sizeof(v4param));
                }
        }
        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_FAIL)
                return -EBUSY;
        else if (val == EINJ_STATUS_INVAL)
                return -EINVAL;

        /*
         * The error is injected into the platform successfully, then it needs
         * to trigger the error.
         */
        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, flags, param1, param2);
                if (rc)
                        return rc;
        }
        rc = apei_exec_run_optional(&ctx, ACPI_EINJ_END_OPERATION);

        return rc;
}

/* Allow almost all types of address except MMIO. */
static bool is_allowed_range(u64 base_addr, u64 size)
{
        int i;
        /*
         * MMIO region is usually claimed with IORESOURCE_MEM + IORES_DESC_NONE.
         * However, IORES_DESC_NONE is treated like a wildcard when we check if
         * region intersects with known resource. So do an allow list check for
         * IORES_DESCs that definitely or most likely not MMIO.
         */
        static const int non_mmio_desc[] = {
                IORES_DESC_CRASH_KERNEL,
                IORES_DESC_ACPI_TABLES,
                IORES_DESC_ACPI_NV_STORAGE,
                IORES_DESC_PERSISTENT_MEMORY,
                IORES_DESC_PERSISTENT_MEMORY_LEGACY,
                /* Treat IORES_DESC_DEVICE_PRIVATE_MEMORY as MMIO. */
                IORES_DESC_RESERVED,
                IORES_DESC_SOFT_RESERVED,
        };

        if (region_intersects(base_addr, size, IORESOURCE_SYSTEM_RAM, IORES_DESC_NONE)
                              == REGION_INTERSECTS)
                return true;

        for (i = 0; i < ARRAY_SIZE(non_mmio_desc); ++i) {
                if (region_intersects(base_addr, size, IORESOURCE_MEM, non_mmio_desc[i])
                                      == REGION_INTERSECTS)
                        return true;
        }

        if (arch_is_platform_page(base_addr))
                return true;

        return false;
}

/* Inject the specified hardware error */
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 | SETWA_FLAGS_EINJV2)))
                return -EINVAL;

        /*
         * Injections targeting a CXL 1.0/1.1 port have to be injected
         * via the einj_cxl_rch_error_inject() path as that does the proper
         * validation of the given RCRB base (MMIO) address.
         */
        if (einj_is_cxl_error_type(type) && (flags & SETWA_FLAGS_MEM))
                return -EINVAL;

        /* check if type is a valid EINJv2 error type */
        if (is_v2) {
                if (!(type & available_error_type_v2))
                        return -EINVAL;
        }

        /* ensure param1/param2 existed */
        if (!(param_extension || acpi5))
                goto inject;

        /*
         * We need extra sanity checks for memory errors.
         * Other types leap directly to injection.
         */
        if (!is_memory_injection(type, flags))
                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
         * as long as is not MMIO.
         */
        base_addr = param1 & param2;
        size = ~param2 + 1;

        if ((param2 & PAGE_MASK) != PAGE_MASK)
                return -EINVAL;

        if (!is_allowed_range(base_addr, size))
                return -EINVAL;

        if (is_zero_pfn(base_addr >> PAGE_SHIFT))
                return -EADDRINUSE;

inject:
        mutex_lock(&einj_mutex);
        rc = __einj_error_inject(type, flags, param1, param2, param3, param4);
        mutex_unlock(&einj_mutex);

        return rc;
}

int einj_cxl_rch_error_inject(u32 type, u32 flags, u64 param1, u64 param2,
                              u64 param3, u64 param4)
{
        int rc;

        if (!(einj_is_cxl_error_type(type) && (flags & SETWA_FLAGS_MEM)))
                return -EINVAL;

        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 char einj_buf[32];
static bool einj_v2_enabled;
static struct { u32 mask; const char *str; } const einj_error_type_string[] = {
        { BIT(0), "Processor Correctable" },
        { BIT(1), "Processor Uncorrectable non-fatal" },
        { BIT(2), "Processor Uncorrectable fatal" },
        { BIT(3), "Memory Correctable" },
        { BIT(4), "Memory Uncorrectable non-fatal" },
        { BIT(5), "Memory Uncorrectable fatal" },
        { BIT(6), "PCI Express Correctable" },
        { BIT(7), "PCI Express Uncorrectable non-fatal" },
        { BIT(8), "PCI Express Uncorrectable fatal" },
        { BIT(9), "Platform Correctable" },
        { BIT(10), "Platform Uncorrectable non-fatal" },
        { BIT(11), "Platform Uncorrectable fatal"},
        { BIT(31), "Vendor Defined Error Types" },
};

static struct { u32 mask; const char *str; } const einjv2_error_type_string[] = {
        { BIT(0), "EINJV2 Processor Error" },
        { BIT(1), "EINJV2 Memory Error" },
        { BIT(2), "EINJV2 PCI Express Error" },
};

static int available_error_type_show(struct seq_file *m, void *v)
{

        for (int pos = 0; pos < ARRAY_SIZE(einj_error_type_string); pos++)
                if (available_error_type & einj_error_type_string[pos].mask)
                        seq_printf(m, "0x%08x\t%s\n", einj_error_type_string[pos].mask,
                                   einj_error_type_string[pos].str);
        if ((available_error_type & ACPI65_EINJV2_SUPP) && einj_v2_enabled) {
                for (int pos = 0; pos < ARRAY_SIZE(einjv2_error_type_string); pos++) {
                        if (available_error_type_v2 & einjv2_error_type_string[pos].mask)
                                seq_printf(m, "V2_0x%08x\t%s\n", einjv2_error_type_string[pos].mask,
                                           einjv2_error_type_string[pos].str);
                }
        }
        return 0;
}

DEFINE_SHOW_ATTRIBUTE(available_error_type);

static ssize_t error_type_get(struct file *file, char __user *buf,
                                size_t count, loff_t *ppos)
{
        return simple_read_from_buffer(buf, count, ppos, einj_buf, strlen(einj_buf));
}

bool einj_is_cxl_error_type(u64 type)
{
        return (type & CXL_ERROR_MASK) && (!(type & ACPI5_VENDOR_BIT));
}

int einj_validate_error_type(u64 type)
{
        u32 tval, vendor;

        /* Only low 32 bits for error type are valid */
        if (type & GENMASK_ULL(63, 32))
                return -EINVAL;

        /*
         * Vendor defined types have 0x80000000 bit set, and
         * are not enumerated by ACPI_EINJ_GET_ERROR_TYPE
         */
        vendor = type & ACPI5_VENDOR_BIT;
        tval = type & GENMASK(30, 0);

        /* Only one error type can be specified */
        if (tval & (tval - 1))
                return -EINVAL;
        if (!vendor)
                if (!(type & (available_error_type | available_error_type_v2)))
                        return -EINVAL;

        return 0;
}

static ssize_t error_type_set(struct file *file, const char __user *buf,
                                size_t count, loff_t *ppos)
{
        int rc;
        u64 val;

        /* Leave the last character for the NUL terminator */
        if (count > sizeof(einj_buf) - 1)
                return -EINVAL;

        memset(einj_buf, 0, sizeof(einj_buf));
        if (copy_from_user(einj_buf, buf, count))
                return -EFAULT;

        if (strncmp(einj_buf, "V2_", 3) == 0) {
                if (!sscanf(einj_buf, "V2_%llx", &val))
                        return -EINVAL;
                is_v2 = true;
        } else {
                if (!sscanf(einj_buf, "%llx", &val))
                        return -EINVAL;
                is_v2 = false;
        }

        rc = einj_validate_error_type(val);
        if (rc)
                return rc;

        error_type = val;

        return count;
}

static const struct file_operations error_type_fops = {
        .read           = error_type_get,
        .write          = error_type_set,
};

static int error_inject_set(void *data, u64 val)
{
        if (!error_type)
                return -EINVAL;

        if (is_v2)
                error_flags |= SETWA_FLAGS_EINJV2;
        else
                error_flags &= ~SETWA_FLAGS_EINJV2;

        return einj_error_inject(error_type, error_flags, error_param1, error_param2,
                error_param3, error_param4);
}

DEFINE_DEBUGFS_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 ssize_t u128_read(struct file *f, char __user *buf, size_t count, loff_t *off)
{
        char output[2 * COMPONENT_LEN + 1];
        u8 *data = f->f_inode->i_private;
        int i;

        if (*off >= sizeof(output))
                return 0;

        for (i = 0; i < COMPONENT_LEN; i++)
                sprintf(output + 2 * i, "%.02x", data[COMPONENT_LEN - i - 1]);
        output[2 * COMPONENT_LEN] = '\n';

        return simple_read_from_buffer(buf, count, off, output, sizeof(output));
}

static ssize_t u128_write(struct file *f, const char __user *buf, size_t count, loff_t *off)
{
        char input[2 + 2 * COMPONENT_LEN + 2];
        u8 *save = f->f_inode->i_private;
        u8 tmp[COMPONENT_LEN];
        char byte[3] = {};
        char *s, *e;
        ssize_t c;
        long val;
        int i;

        /* Require that user supply whole input line in one write(2) syscall */
        if (*off)
                return -EINVAL;

        c = simple_write_to_buffer(input, sizeof(input), off, buf, count);
        if (c < 0)
                return c;

        if (c < 1 || input[c - 1] != '\n')
                return -EINVAL;

        /* Empty line means invalidate this entry */
        if (c == 1) {
                memset(save, 0xff, COMPONENT_LEN);
                return c;
        }

        if (input[0] == '0' && (input[1] == 'x' || input[1] == 'X'))
                s = input + 2;
        else
                s = input;
        e = input + c - 1;

        for (i = 0; i < COMPONENT_LEN; i++) {
                byte[1] = *--e;
                byte[0] = e > s ? *--e : '0';
                if (kstrtol(byte, 16, &val))
                        return -EINVAL;
                tmp[i] = val;
                if (e <= s)
                        break;
        }
        while (++i < COMPONENT_LEN)
                tmp[i] = 0;

        memcpy(save, tmp, COMPONENT_LEN);

        return c;
}

static const struct file_operations u128_fops = {
        .read   = u128_read,
        .write  = u128_write,
};

static bool setup_einjv2_component_files(void)
{
        char name[32];

        syndrome_data = kzalloc_objs(syndrome_data[0], max_nr_components);
        if (!syndrome_data)
                return false;

        for (int i = 0; i < max_nr_components; i++) {
                sprintf(name, "component_id%d", i);
                debugfs_create_file(name, 0600, einj_debug_dir,
                                    &syndrome_data[i].comp_id, &u128_fops);
                sprintf(name, "component_syndrome%d", i);
                debugfs_create_file(name, 0600, einj_debug_dir,
                                    &syndrome_data[i].comp_synd, &u128_fops);
        }

        return true;
}

static int __init einj_probe(struct faux_device *fdev)
{
        int rc;
        acpi_status status;
        struct apei_exec_context ctx;

        status = acpi_get_table(ACPI_SIG_EINJ, 0,
                                (struct acpi_table_header **)&einj_tab);
        if (status == AE_NOT_FOUND) {
                pr_debug("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");
                goto err_put_table;
        }

        rc = einj_get_available_error_types(&available_error_type, &available_error_type_v2);
        if (rc)
                goto err_put_table;

        rc = -ENOMEM;
        einj_debug_dir = debugfs_create_dir("einj", apei_get_debugfs_dir());

        debugfs_create_file("available_error_type", S_IRUSR, einj_debug_dir,
                            NULL, &available_error_type_fops);
        debugfs_create_file_unsafe("error_type", 0600, einj_debug_dir,
                                   NULL, &error_type_fops);
        debugfs_create_file_unsafe("error_inject", 0200, einj_debug_dir,
                                   NULL, &error_inject_fops);

        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;
        }

        einj_param = einj_get_parameter_address();
        if ((param_extension || acpi5) && einj_param) {
                debugfs_create_x32("flags", S_IRUSR | S_IWUSR, einj_debug_dir,
                                   &error_flags);
                debugfs_create_x64("param1", S_IRUSR | S_IWUSR, einj_debug_dir,
                                   &error_param1);
                debugfs_create_x64("param2", S_IRUSR | S_IWUSR, einj_debug_dir,
                                   &error_param2);
                debugfs_create_x64("param3", S_IRUSR | S_IWUSR, einj_debug_dir,
                                   &error_param3);
                debugfs_create_x64("param4", S_IRUSR | S_IWUSR, einj_debug_dir,
                                   &error_param4);
                debugfs_create_x32("notrigger", S_IRUSR | S_IWUSR,
                                   einj_debug_dir, &notrigger);
                if (available_error_type & ACPI65_EINJV2_SUPP)
                        einj_v2_enabled = setup_einjv2_component_files();
        }

        if (vendor_dev[0]) {
                vendor_blob.data = vendor_dev;
                vendor_blob.size = strlen(vendor_dev);
                debugfs_create_blob("vendor", S_IRUSR, einj_debug_dir,
                                    &vendor_blob);
                debugfs_create_x32("vendor_flags", S_IRUSR | S_IWUSR,
                                   einj_debug_dir, &vendor_flags);
        }

        if (vendor_errors.size)
                debugfs_create_blob("oem_error", 0600, einj_debug_dir,
                                    &vendor_errors);

        pr_info("Error INJection is initialized.\n");

        return 0;

err_release:
        apei_resources_release(&einj_resources);
err_fini:
        apei_resources_fini(&einj_resources);
        debugfs_remove_recursive(einj_debug_dir);
err_put_table:
        acpi_put_table((struct acpi_table_header *)einj_tab);

        return rc;
}

static void einj_remove(struct faux_device *fdev)
{
        struct apei_exec_context ctx;

        if (einj_param) {
                acpi_size size;

                if (v66param_size)
                        size = v66param_size;
                else if (acpi5)
                        size = v5param_size;
                else
                        size = sizeof(struct einj_parameter);

                acpi_os_unmap_iomem(einj_param, size);
                if (vendor_errors.size)
                        acpi_os_unmap_memory(vendor_errors.data, vendor_errors.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);
        kfree(syndrome_data);
        acpi_put_table((struct acpi_table_header *)einj_tab);
}

static struct faux_device *einj_dev;
static struct faux_device_ops einj_device_ops = {
        .probe = einj_probe,
        .remove = einj_remove,
};

static int __init einj_init(void)
{
        if (acpi_disabled) {
                pr_debug("ACPI disabled.\n");
                return -ENODEV;
        }

        einj_dev = faux_device_create("acpi-einj", NULL, &einj_device_ops);

        if (einj_dev)
                einj_initialized = true;

        return 0;
}

static void __exit einj_exit(void)
{
        faux_device_destroy(einj_dev);
}

module_init(einj_init);
module_exit(einj_exit);

MODULE_AUTHOR("Huang Ying");
MODULE_DESCRIPTION("APEI Error INJection support");
MODULE_LICENSE("GPL");