// SPDX-License-Identifier: GPL-2.0-only
// Copyright(c) 2021 Intel Corporation. All rights reserved.

#include <linux/platform_device.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/sizes.h>
#include <linux/bits.h>
#include <asm/unaligned.h>
#include <cxlmem.h>

#include "trace.h"

#define LSA_SIZE SZ_128K
#define DEV_SIZE SZ_2G
#define EFFECT(x) (1U << x)

#define MOCK_INJECT_DEV_MAX 8
#define MOCK_INJECT_TEST_MAX 128

static unsigned int poison_inject_dev_max = MOCK_INJECT_DEV_MAX;

static struct cxl_cel_entry mock_cel[] = {
	{
		.opcode = cpu_to_le16(CXL_MBOX_OP_GET_SUPPORTED_LOGS),
		.effect = cpu_to_le16(0),
	},
	{
		.opcode = cpu_to_le16(CXL_MBOX_OP_IDENTIFY),
		.effect = cpu_to_le16(0),
	},
	{
		.opcode = cpu_to_le16(CXL_MBOX_OP_GET_LSA),
		.effect = cpu_to_le16(0),
	},
	{
		.opcode = cpu_to_le16(CXL_MBOX_OP_GET_PARTITION_INFO),
		.effect = cpu_to_le16(0),
	},
	{
		.opcode = cpu_to_le16(CXL_MBOX_OP_SET_LSA),
		.effect = cpu_to_le16(EFFECT(1) | EFFECT(2)),
	},
	{
		.opcode = cpu_to_le16(CXL_MBOX_OP_GET_HEALTH_INFO),
		.effect = cpu_to_le16(0),
	},
	{
		.opcode = cpu_to_le16(CXL_MBOX_OP_GET_POISON),
		.effect = cpu_to_le16(0),
	},
	{
		.opcode = cpu_to_le16(CXL_MBOX_OP_INJECT_POISON),
		.effect = cpu_to_le16(0),
	},
	{
		.opcode = cpu_to_le16(CXL_MBOX_OP_CLEAR_POISON),
		.effect = cpu_to_le16(0),
	},
};

/* See CXL 2.0 Table 181 Get Health Info Output Payload */
struct cxl_mbox_health_info {
	u8 health_status;
	u8 media_status;
	u8 ext_status;
	u8 life_used;
	__le16 temperature;
	__le32 dirty_shutdowns;
	__le32 volatile_errors;
	__le32 pmem_errors;
} __packed;

static struct {
	struct cxl_mbox_get_supported_logs gsl;
	struct cxl_gsl_entry entry;
} mock_gsl_payload = {
	.gsl = {
		.entries = cpu_to_le16(1),
	},
	.entry = {
		.uuid = DEFINE_CXL_CEL_UUID,
		.size = cpu_to_le32(sizeof(mock_cel)),
	},
};

#define PASS_TRY_LIMIT 3

#define CXL_TEST_EVENT_CNT_MAX 15

/* Set a number of events to return at a time for simulation.  */
#define CXL_TEST_EVENT_CNT 3

struct mock_event_log {
	u16 clear_idx;
	u16 cur_idx;
	u16 nr_events;
	u16 nr_overflow;
	u16 overflow_reset;
	struct cxl_event_record_raw *events[CXL_TEST_EVENT_CNT_MAX];
};

struct mock_event_store {
	struct cxl_dev_state *cxlds;
	struct mock_event_log mock_logs[CXL_EVENT_TYPE_MAX];
	u32 ev_status;
};

struct cxl_mockmem_data {
	void *lsa;
	u32 security_state;
	u8 user_pass[NVDIMM_PASSPHRASE_LEN];
	u8 master_pass[NVDIMM_PASSPHRASE_LEN];
	int user_limit;
	int master_limit;
	struct mock_event_store mes;
	u8 event_buf[SZ_4K];
	u64 timestamp;
};

static struct mock_event_log *event_find_log(struct device *dev, int log_type)
{
	struct cxl_mockmem_data *mdata = dev_get_drvdata(dev);

	if (log_type >= CXL_EVENT_TYPE_MAX)
		return NULL;
	return &mdata->mes.mock_logs[log_type];
}

static struct cxl_event_record_raw *event_get_current(struct mock_event_log *log)
{
	return log->events[log->cur_idx];
}

static void event_reset_log(struct mock_event_log *log)
{
	log->cur_idx = 0;
	log->clear_idx = 0;
	log->nr_overflow = log->overflow_reset;
}

/* Handle can never be 0 use 1 based indexing for handle */
static u16 event_get_clear_handle(struct mock_event_log *log)
{
	return log->clear_idx + 1;
}

/* Handle can never be 0 use 1 based indexing for handle */
static __le16 event_get_cur_event_handle(struct mock_event_log *log)
{
	u16 cur_handle = log->cur_idx + 1;

	return cpu_to_le16(cur_handle);
}

static bool event_log_empty(struct mock_event_log *log)
{
	return log->cur_idx == log->nr_events;
}

static void mes_add_event(struct mock_event_store *mes,
			  enum cxl_event_log_type log_type,
			  struct cxl_event_record_raw *event)
{
	struct mock_event_log *log;

	if (WARN_ON(log_type >= CXL_EVENT_TYPE_MAX))
		return;

	log = &mes->mock_logs[log_type];

	if ((log->nr_events + 1) > CXL_TEST_EVENT_CNT_MAX) {
		log->nr_overflow++;
		log->overflow_reset = log->nr_overflow;
		return;
	}

	log->events[log->nr_events] = event;
	log->nr_events++;
}

static int mock_get_event(struct cxl_dev_state *cxlds,
			  struct cxl_mbox_cmd *cmd)
{
	struct cxl_get_event_payload *pl;
	struct mock_event_log *log;
	u16 nr_overflow;
	u8 log_type;
	int i;

	if (cmd->size_in != sizeof(log_type))
		return -EINVAL;

	if (cmd->size_out < struct_size(pl, records, CXL_TEST_EVENT_CNT))
		return -EINVAL;

	log_type = *((u8 *)cmd->payload_in);
	if (log_type >= CXL_EVENT_TYPE_MAX)
		return -EINVAL;

	memset(cmd->payload_out, 0, cmd->size_out);

	log = event_find_log(cxlds->dev, log_type);
	if (!log || event_log_empty(log))
		return 0;

	pl = cmd->payload_out;

	for (i = 0; i < CXL_TEST_EVENT_CNT && !event_log_empty(log); i++) {
		memcpy(&pl->records[i], event_get_current(log),
		       sizeof(pl->records[i]));
		pl->records[i].hdr.handle = event_get_cur_event_handle(log);
		log->cur_idx++;
	}

	pl->record_count = cpu_to_le16(i);
	if (!event_log_empty(log))
		pl->flags |= CXL_GET_EVENT_FLAG_MORE_RECORDS;

	if (log->nr_overflow) {
		u64 ns;

		pl->flags |= CXL_GET_EVENT_FLAG_OVERFLOW;
		pl->overflow_err_count = cpu_to_le16(nr_overflow);
		ns = ktime_get_real_ns();
		ns -= 5000000000; /* 5s ago */
		pl->first_overflow_timestamp = cpu_to_le64(ns);
		ns = ktime_get_real_ns();
		ns -= 1000000000; /* 1s ago */
		pl->last_overflow_timestamp = cpu_to_le64(ns);
	}

	return 0;
}

static int mock_clear_event(struct cxl_dev_state *cxlds,
			    struct cxl_mbox_cmd *cmd)
{
	struct cxl_mbox_clear_event_payload *pl = cmd->payload_in;
	struct mock_event_log *log;
	u8 log_type = pl->event_log;
	u16 handle;
	int nr;

	if (log_type >= CXL_EVENT_TYPE_MAX)
		return -EINVAL;

	log = event_find_log(cxlds->dev, log_type);
	if (!log)
		return 0; /* No mock data in this log */

	/*
	 * This check is technically not invalid per the specification AFAICS.
	 * (The host could 'guess' handles and clear them in order).
	 * However, this is not good behavior for the host so test it.
	 */
	if (log->clear_idx + pl->nr_recs > log->cur_idx) {
		dev_err(cxlds->dev,
			"Attempting to clear more events than returned!\n");
		return -EINVAL;
	}

	/* Check handle order prior to clearing events */
	for (nr = 0, handle = event_get_clear_handle(log);
	     nr < pl->nr_recs;
	     nr++, handle++) {
		if (handle != le16_to_cpu(pl->handles[nr])) {
			dev_err(cxlds->dev, "Clearing events out of order\n");
			return -EINVAL;
		}
	}

	if (log->nr_overflow)
		log->nr_overflow = 0;

	/* Clear events */
	log->clear_idx += pl->nr_recs;
	return 0;
}

static void cxl_mock_event_trigger(struct device *dev)
{
	struct cxl_mockmem_data *mdata = dev_get_drvdata(dev);
	struct mock_event_store *mes = &mdata->mes;
	int i;

	for (i = CXL_EVENT_TYPE_INFO; i < CXL_EVENT_TYPE_MAX; i++) {
		struct mock_event_log *log;

		log = event_find_log(dev, i);
		if (log)
			event_reset_log(log);
	}

	cxl_mem_get_event_records(mes->cxlds, mes->ev_status);
}

struct cxl_event_record_raw maint_needed = {
	.hdr = {
		.id = UUID_INIT(0xBA5EBA11, 0xABCD, 0xEFEB,
				0xa5, 0x5a, 0xa5, 0x5a, 0xa5, 0xa5, 0x5a, 0xa5),
		.length = sizeof(struct cxl_event_record_raw),
		.flags[0] = CXL_EVENT_RECORD_FLAG_MAINT_NEEDED,
		/* .handle = Set dynamically */
		.related_handle = cpu_to_le16(0xa5b6),
	},
	.data = { 0xDE, 0xAD, 0xBE, 0xEF },
};

struct cxl_event_record_raw hardware_replace = {
	.hdr = {
		.id = UUID_INIT(0xABCDEFEB, 0xBA11, 0xBA5E,
				0xa5, 0x5a, 0xa5, 0x5a, 0xa5, 0xa5, 0x5a, 0xa5),
		.length = sizeof(struct cxl_event_record_raw),
		.flags[0] = CXL_EVENT_RECORD_FLAG_HW_REPLACE,
		/* .handle = Set dynamically */
		.related_handle = cpu_to_le16(0xb6a5),
	},
	.data = { 0xDE, 0xAD, 0xBE, 0xEF },
};

struct cxl_event_gen_media gen_media = {
	.hdr = {
		.id = UUID_INIT(0xfbcd0a77, 0xc260, 0x417f,
				0x85, 0xa9, 0x08, 0x8b, 0x16, 0x21, 0xeb, 0xa6),
		.length = sizeof(struct cxl_event_gen_media),
		.flags[0] = CXL_EVENT_RECORD_FLAG_PERMANENT,
		/* .handle = Set dynamically */
		.related_handle = cpu_to_le16(0),
	},
	.phys_addr = cpu_to_le64(0x2000),
	.descriptor = CXL_GMER_EVT_DESC_UNCORECTABLE_EVENT,
	.type = CXL_GMER_MEM_EVT_TYPE_DATA_PATH_ERROR,
	.transaction_type = CXL_GMER_TRANS_HOST_WRITE,
	/* .validity_flags = <set below> */
	.channel = 1,
	.rank = 30
};

struct cxl_event_dram dram = {
	.hdr = {
		.id = UUID_INIT(0x601dcbb3, 0x9c06, 0x4eab,
				0xb8, 0xaf, 0x4e, 0x9b, 0xfb, 0x5c, 0x96, 0x24),
		.length = sizeof(struct cxl_event_dram),
		.flags[0] = CXL_EVENT_RECORD_FLAG_PERF_DEGRADED,
		/* .handle = Set dynamically */
		.related_handle = cpu_to_le16(0),
	},
	.phys_addr = cpu_to_le64(0x8000),
	.descriptor = CXL_GMER_EVT_DESC_THRESHOLD_EVENT,
	.type = CXL_GMER_MEM_EVT_TYPE_INV_ADDR,
	.transaction_type = CXL_GMER_TRANS_INTERNAL_MEDIA_SCRUB,
	/* .validity_flags = <set below> */
	.channel = 1,
	.bank_group = 5,
	.bank = 2,
	.column = {0xDE, 0xAD},
};

struct cxl_event_mem_module mem_module = {
	.hdr = {
		.id = UUID_INIT(0xfe927475, 0xdd59, 0x4339,
				0xa5, 0x86, 0x79, 0xba, 0xb1, 0x13, 0xb7, 0x74),
		.length = sizeof(struct cxl_event_mem_module),
		/* .handle = Set dynamically */
		.related_handle = cpu_to_le16(0),
	},
	.event_type = CXL_MMER_TEMP_CHANGE,
	.info = {
		.health_status = CXL_DHI_HS_PERFORMANCE_DEGRADED,
		.media_status = CXL_DHI_MS_ALL_DATA_LOST,
		.add_status = (CXL_DHI_AS_CRITICAL << 2) |
			      (CXL_DHI_AS_WARNING << 4) |
			      (CXL_DHI_AS_WARNING << 5),
		.device_temp = { 0xDE, 0xAD},
		.dirty_shutdown_cnt = { 0xde, 0xad, 0xbe, 0xef },
		.cor_vol_err_cnt = { 0xde, 0xad, 0xbe, 0xef },
		.cor_per_err_cnt = { 0xde, 0xad, 0xbe, 0xef },
	}
};

static int mock_set_timestamp(struct cxl_dev_state *cxlds,
			      struct cxl_mbox_cmd *cmd)
{
	struct cxl_mockmem_data *mdata = dev_get_drvdata(cxlds->dev);
	struct cxl_mbox_set_timestamp_in *ts = cmd->payload_in;

	if (cmd->size_in != sizeof(*ts))
		return -EINVAL;

	if (cmd->size_out != 0)
		return -EINVAL;

	mdata->timestamp = le64_to_cpu(ts->timestamp);
	return 0;
}

static void cxl_mock_add_event_logs(struct mock_event_store *mes)
{
	put_unaligned_le16(CXL_GMER_VALID_CHANNEL | CXL_GMER_VALID_RANK,
			   &gen_media.validity_flags);

	put_unaligned_le16(CXL_DER_VALID_CHANNEL | CXL_DER_VALID_BANK_GROUP |
			   CXL_DER_VALID_BANK | CXL_DER_VALID_COLUMN,
			   &dram.validity_flags);

	mes_add_event(mes, CXL_EVENT_TYPE_INFO, &maint_needed);
	mes_add_event(mes, CXL_EVENT_TYPE_INFO,
		      (struct cxl_event_record_raw *)&gen_media);
	mes_add_event(mes, CXL_EVENT_TYPE_INFO,
		      (struct cxl_event_record_raw *)&mem_module);
	mes->ev_status |= CXLDEV_EVENT_STATUS_INFO;

	mes_add_event(mes, CXL_EVENT_TYPE_FAIL, &maint_needed);
	mes_add_event(mes, CXL_EVENT_TYPE_FAIL, &hardware_replace);
	mes_add_event(mes, CXL_EVENT_TYPE_FAIL,
		      (struct cxl_event_record_raw *)&dram);
	mes_add_event(mes, CXL_EVENT_TYPE_FAIL,
		      (struct cxl_event_record_raw *)&gen_media);
	mes_add_event(mes, CXL_EVENT_TYPE_FAIL,
		      (struct cxl_event_record_raw *)&mem_module);
	mes_add_event(mes, CXL_EVENT_TYPE_FAIL, &hardware_replace);
	mes_add_event(mes, CXL_EVENT_TYPE_FAIL,
		      (struct cxl_event_record_raw *)&dram);
	/* Overflow this log */
	mes_add_event(mes, CXL_EVENT_TYPE_FAIL, &hardware_replace);
	mes_add_event(mes, CXL_EVENT_TYPE_FAIL, &hardware_replace);
	mes_add_event(mes, CXL_EVENT_TYPE_FAIL, &hardware_replace);
	mes_add_event(mes, CXL_EVENT_TYPE_FAIL, &hardware_replace);
	mes_add_event(mes, CXL_EVENT_TYPE_FAIL, &hardware_replace);
	mes_add_event(mes, CXL_EVENT_TYPE_FAIL, &hardware_replace);
	mes_add_event(mes, CXL_EVENT_TYPE_FAIL, &hardware_replace);
	mes_add_event(mes, CXL_EVENT_TYPE_FAIL, &hardware_replace);
	mes_add_event(mes, CXL_EVENT_TYPE_FAIL, &hardware_replace);
	mes_add_event(mes, CXL_EVENT_TYPE_FAIL, &hardware_replace);
	mes->ev_status |= CXLDEV_EVENT_STATUS_FAIL;

	mes_add_event(mes, CXL_EVENT_TYPE_FATAL, &hardware_replace);
	mes_add_event(mes, CXL_EVENT_TYPE_FATAL,
		      (struct cxl_event_record_raw *)&dram);
	mes->ev_status |= CXLDEV_EVENT_STATUS_FATAL;
}

static int mock_gsl(struct cxl_mbox_cmd *cmd)
{
	if (cmd->size_out < sizeof(mock_gsl_payload))
		return -EINVAL;

	memcpy(cmd->payload_out, &mock_gsl_payload, sizeof(mock_gsl_payload));
	cmd->size_out = sizeof(mock_gsl_payload);

	return 0;
}

static int mock_get_log(struct cxl_dev_state *cxlds, struct cxl_mbox_cmd *cmd)
{
	struct cxl_mbox_get_log *gl = cmd->payload_in;
	u32 offset = le32_to_cpu(gl->offset);
	u32 length = le32_to_cpu(gl->length);
	uuid_t uuid = DEFINE_CXL_CEL_UUID;
	void *data = &mock_cel;

	if (cmd->size_in < sizeof(*gl))
		return -EINVAL;
	if (length > cxlds->payload_size)
		return -EINVAL;
	if (offset + length > sizeof(mock_cel))
		return -EINVAL;
	if (!uuid_equal(&gl->uuid, &uuid))
		return -EINVAL;
	if (length > cmd->size_out)
		return -EINVAL;

	memcpy(cmd->payload_out, data + offset, length);

	return 0;
}

static int mock_rcd_id(struct cxl_dev_state *cxlds, struct cxl_mbox_cmd *cmd)
{
	struct cxl_mbox_identify id = {
		.fw_revision = { "mock fw v1 " },
		.total_capacity =
			cpu_to_le64(DEV_SIZE / CXL_CAPACITY_MULTIPLIER),
		.volatile_capacity =
			cpu_to_le64(DEV_SIZE / CXL_CAPACITY_MULTIPLIER),
	};

	if (cmd->size_out < sizeof(id))
		return -EINVAL;

	memcpy(cmd->payload_out, &id, sizeof(id));

	return 0;
}

static int mock_id(struct cxl_dev_state *cxlds, struct cxl_mbox_cmd *cmd)
{
	struct cxl_mbox_identify id = {
		.fw_revision = { "mock fw v1 " },
		.lsa_size = cpu_to_le32(LSA_SIZE),
		.partition_align =
			cpu_to_le64(SZ_256M / CXL_CAPACITY_MULTIPLIER),
		.total_capacity =
			cpu_to_le64(DEV_SIZE / CXL_CAPACITY_MULTIPLIER),
		.inject_poison_limit = cpu_to_le16(MOCK_INJECT_TEST_MAX),
	};

	put_unaligned_le24(CXL_POISON_LIST_MAX, id.poison_list_max_mer);

	if (cmd->size_out < sizeof(id))
		return -EINVAL;

	memcpy(cmd->payload_out, &id, sizeof(id));

	return 0;
}

static int mock_partition_info(struct cxl_dev_state *cxlds,
			       struct cxl_mbox_cmd *cmd)
{
	struct cxl_mbox_get_partition_info pi = {
		.active_volatile_cap =
			cpu_to_le64(DEV_SIZE / 2 / CXL_CAPACITY_MULTIPLIER),
		.active_persistent_cap =
			cpu_to_le64(DEV_SIZE / 2 / CXL_CAPACITY_MULTIPLIER),
	};

	if (cmd->size_out < sizeof(pi))
		return -EINVAL;

	memcpy(cmd->payload_out, &pi, sizeof(pi));

	return 0;
}

static int mock_get_security_state(struct cxl_dev_state *cxlds,
				   struct cxl_mbox_cmd *cmd)
{
	struct cxl_mockmem_data *mdata = dev_get_drvdata(cxlds->dev);

	if (cmd->size_in)
		return -EINVAL;

	if (cmd->size_out != sizeof(u32))
		return -EINVAL;

	memcpy(cmd->payload_out, &mdata->security_state, sizeof(u32));

	return 0;
}

static void master_plimit_check(struct cxl_mockmem_data *mdata)
{
	if (mdata->master_limit == PASS_TRY_LIMIT)
		return;
	mdata->master_limit++;
	if (mdata->master_limit == PASS_TRY_LIMIT)
		mdata->security_state |= CXL_PMEM_SEC_STATE_MASTER_PLIMIT;
}

static void user_plimit_check(struct cxl_mockmem_data *mdata)
{
	if (mdata->user_limit == PASS_TRY_LIMIT)
		return;
	mdata->user_limit++;
	if (mdata->user_limit == PASS_TRY_LIMIT)
		mdata->security_state |= CXL_PMEM_SEC_STATE_USER_PLIMIT;
}

static int mock_set_passphrase(struct cxl_dev_state *cxlds, struct cxl_mbox_cmd *cmd)
{
	struct cxl_mockmem_data *mdata = dev_get_drvdata(cxlds->dev);
	struct cxl_set_pass *set_pass;

	if (cmd->size_in != sizeof(*set_pass))
		return -EINVAL;

	if (cmd->size_out != 0)
		return -EINVAL;

	if (mdata->security_state & CXL_PMEM_SEC_STATE_FROZEN) {
		cmd->return_code = CXL_MBOX_CMD_RC_SECURITY;
		return -ENXIO;
	}

	set_pass = cmd->payload_in;
	switch (set_pass->type) {
	case CXL_PMEM_SEC_PASS_MASTER:
		if (mdata->security_state & CXL_PMEM_SEC_STATE_MASTER_PLIMIT) {
			cmd->return_code = CXL_MBOX_CMD_RC_SECURITY;
			return -ENXIO;
		}
		/*
		 * CXL spec rev3.0 8.2.9.8.6.2, The master pasphrase shall only be set in
		 * the security disabled state when the user passphrase is not set.
		 */
		if (mdata->security_state & CXL_PMEM_SEC_STATE_USER_PASS_SET) {
			cmd->return_code = CXL_MBOX_CMD_RC_SECURITY;
			return -ENXIO;
		}
		if (memcmp(mdata->master_pass, set_pass->old_pass, NVDIMM_PASSPHRASE_LEN)) {
			master_plimit_check(mdata);
			cmd->return_code = CXL_MBOX_CMD_RC_PASSPHRASE;
			return -ENXIO;
		}
		memcpy(mdata->master_pass, set_pass->new_pass, NVDIMM_PASSPHRASE_LEN);
		mdata->security_state |= CXL_PMEM_SEC_STATE_MASTER_PASS_SET;
		return 0;

	case CXL_PMEM_SEC_PASS_USER:
		if (mdata->security_state & CXL_PMEM_SEC_STATE_USER_PLIMIT) {
			cmd->return_code = CXL_MBOX_CMD_RC_SECURITY;
			return -ENXIO;
		}
		if (memcmp(mdata->user_pass, set_pass->old_pass, NVDIMM_PASSPHRASE_LEN)) {
			user_plimit_check(mdata);
			cmd->return_code = CXL_MBOX_CMD_RC_PASSPHRASE;
			return -ENXIO;
		}
		memcpy(mdata->user_pass, set_pass->new_pass, NVDIMM_PASSPHRASE_LEN);
		mdata->security_state |= CXL_PMEM_SEC_STATE_USER_PASS_SET;
		return 0;

	default:
		cmd->return_code = CXL_MBOX_CMD_RC_INPUT;
	}
	return -EINVAL;
}

static int mock_disable_passphrase(struct cxl_dev_state *cxlds, struct cxl_mbox_cmd *cmd)
{
	struct cxl_mockmem_data *mdata = dev_get_drvdata(cxlds->dev);
	struct cxl_disable_pass *dis_pass;

	if (cmd->size_in != sizeof(*dis_pass))
		return -EINVAL;

	if (cmd->size_out != 0)
		return -EINVAL;

	if (mdata->security_state & CXL_PMEM_SEC_STATE_FROZEN) {
		cmd->return_code = CXL_MBOX_CMD_RC_SECURITY;
		return -ENXIO;
	}

	dis_pass = cmd->payload_in;
	switch (dis_pass->type) {
	case CXL_PMEM_SEC_PASS_MASTER:
		if (mdata->security_state & CXL_PMEM_SEC_STATE_MASTER_PLIMIT) {
			cmd->return_code = CXL_MBOX_CMD_RC_SECURITY;
			return -ENXIO;
		}

		if (!(mdata->security_state & CXL_PMEM_SEC_STATE_MASTER_PASS_SET)) {
			cmd->return_code = CXL_MBOX_CMD_RC_SECURITY;
			return -ENXIO;
		}

		if (memcmp(dis_pass->pass, mdata->master_pass, NVDIMM_PASSPHRASE_LEN)) {
			master_plimit_check(mdata);
			cmd->return_code = CXL_MBOX_CMD_RC_PASSPHRASE;
			return -ENXIO;
		}

		mdata->master_limit = 0;
		memset(mdata->master_pass, 0, NVDIMM_PASSPHRASE_LEN);
		mdata->security_state &= ~CXL_PMEM_SEC_STATE_MASTER_PASS_SET;
		return 0;

	case CXL_PMEM_SEC_PASS_USER:
		if (mdata->security_state & CXL_PMEM_SEC_STATE_USER_PLIMIT) {
			cmd->return_code = CXL_MBOX_CMD_RC_SECURITY;
			return -ENXIO;
		}

		if (!(mdata->security_state & CXL_PMEM_SEC_STATE_USER_PASS_SET)) {
			cmd->return_code = CXL_MBOX_CMD_RC_SECURITY;
			return -ENXIO;
		}

		if (memcmp(dis_pass->pass, mdata->user_pass, NVDIMM_PASSPHRASE_LEN)) {
			user_plimit_check(mdata);
			cmd->return_code = CXL_MBOX_CMD_RC_PASSPHRASE;
			return -ENXIO;
		}

		mdata->user_limit = 0;
		memset(mdata->user_pass, 0, NVDIMM_PASSPHRASE_LEN);
		mdata->security_state &= ~(CXL_PMEM_SEC_STATE_USER_PASS_SET |
					   CXL_PMEM_SEC_STATE_LOCKED);
		return 0;

	default:
		cmd->return_code = CXL_MBOX_CMD_RC_INPUT;
		return -EINVAL;
	}

	return 0;
}

static int mock_freeze_security(struct cxl_dev_state *cxlds, struct cxl_mbox_cmd *cmd)
{
	struct cxl_mockmem_data *mdata = dev_get_drvdata(cxlds->dev);

	if (cmd->size_in != 0)
		return -EINVAL;

	if (cmd->size_out != 0)
		return -EINVAL;

	if (mdata->security_state & CXL_PMEM_SEC_STATE_FROZEN)
		return 0;

	mdata->security_state |= CXL_PMEM_SEC_STATE_FROZEN;
	return 0;
}

static int mock_unlock_security(struct cxl_dev_state *cxlds, struct cxl_mbox_cmd *cmd)
{
	struct cxl_mockmem_data *mdata = dev_get_drvdata(cxlds->dev);

	if (cmd->size_in != NVDIMM_PASSPHRASE_LEN)
		return -EINVAL;

	if (cmd->size_out != 0)
		return -EINVAL;

	if (mdata->security_state & CXL_PMEM_SEC_STATE_FROZEN) {
		cmd->return_code = CXL_MBOX_CMD_RC_SECURITY;
		return -ENXIO;
	}

	if (!(mdata->security_state & CXL_PMEM_SEC_STATE_USER_PASS_SET)) {
		cmd->return_code = CXL_MBOX_CMD_RC_SECURITY;
		return -ENXIO;
	}

	if (mdata->security_state & CXL_PMEM_SEC_STATE_USER_PLIMIT) {
		cmd->return_code = CXL_MBOX_CMD_RC_SECURITY;
		return -ENXIO;
	}

	if (!(mdata->security_state & CXL_PMEM_SEC_STATE_LOCKED)) {
		cmd->return_code = CXL_MBOX_CMD_RC_SECURITY;
		return -ENXIO;
	}

	if (memcmp(cmd->payload_in, mdata->user_pass, NVDIMM_PASSPHRASE_LEN)) {
		if (++mdata->user_limit == PASS_TRY_LIMIT)
			mdata->security_state |= CXL_PMEM_SEC_STATE_USER_PLIMIT;
		cmd->return_code = CXL_MBOX_CMD_RC_PASSPHRASE;
		return -ENXIO;
	}

	mdata->user_limit = 0;
	mdata->security_state &= ~CXL_PMEM_SEC_STATE_LOCKED;
	return 0;
}

static int mock_passphrase_secure_erase(struct cxl_dev_state *cxlds,
					struct cxl_mbox_cmd *cmd)
{
	struct cxl_mockmem_data *mdata = dev_get_drvdata(cxlds->dev);
	struct cxl_pass_erase *erase;

	if (cmd->size_in != sizeof(*erase))
		return -EINVAL;

	if (cmd->size_out != 0)
		return -EINVAL;

	erase = cmd->payload_in;
	if (mdata->security_state & CXL_PMEM_SEC_STATE_FROZEN) {
		cmd->return_code = CXL_MBOX_CMD_RC_SECURITY;
		return -ENXIO;
	}

	if (mdata->security_state & CXL_PMEM_SEC_STATE_USER_PLIMIT &&
	    erase->type == CXL_PMEM_SEC_PASS_USER) {
		cmd->return_code = CXL_MBOX_CMD_RC_SECURITY;
		return -ENXIO;
	}

	if (mdata->security_state & CXL_PMEM_SEC_STATE_MASTER_PLIMIT &&
	    erase->type == CXL_PMEM_SEC_PASS_MASTER) {
		cmd->return_code = CXL_MBOX_CMD_RC_SECURITY;
		return -ENXIO;
	}

	switch (erase->type) {
	case CXL_PMEM_SEC_PASS_MASTER:
		/*
		 * The spec does not clearly define the behavior of the scenario
		 * where a master passphrase is passed in while the master
		 * passphrase is not set and user passphrase is not set. The
		 * code will take the assumption that it will behave the same
		 * as a CXL secure erase command without passphrase (0x4401).
		 */
		if (mdata->security_state & CXL_PMEM_SEC_STATE_MASTER_PASS_SET) {
			if (memcmp(mdata->master_pass, erase->pass,
				   NVDIMM_PASSPHRASE_LEN)) {
				master_plimit_check(mdata);
				cmd->return_code = CXL_MBOX_CMD_RC_PASSPHRASE;
				return -ENXIO;
			}
			mdata->master_limit = 0;
			mdata->user_limit = 0;
			mdata->security_state &= ~CXL_PMEM_SEC_STATE_USER_PASS_SET;
			memset(mdata->user_pass, 0, NVDIMM_PASSPHRASE_LEN);
			mdata->security_state &= ~CXL_PMEM_SEC_STATE_LOCKED;
		} else {
			/*
			 * CXL rev3 8.2.9.8.6.3 Disable Passphrase
			 * When master passphrase is disabled, the device shall
			 * return Invalid Input for the Passphrase Secure Erase
			 * command with master passphrase.
			 */
			return -EINVAL;
		}
		/* Scramble encryption keys so that data is effectively erased */
		break;
	case CXL_PMEM_SEC_PASS_USER:
		/*
		 * The spec does not clearly define the behavior of the scenario
		 * where a user passphrase is passed in while the user
		 * passphrase is not set. The code will take the assumption that
		 * it will behave the same as a CXL secure erase command without
		 * passphrase (0x4401).
		 */
		if (mdata->security_state & CXL_PMEM_SEC_STATE_USER_PASS_SET) {
			if (memcmp(mdata->user_pass, erase->pass,
				   NVDIMM_PASSPHRASE_LEN)) {
				user_plimit_check(mdata);
				cmd->return_code = CXL_MBOX_CMD_RC_PASSPHRASE;
				return -ENXIO;
			}
			mdata->user_limit = 0;
			mdata->security_state &= ~CXL_PMEM_SEC_STATE_USER_PASS_SET;
			memset(mdata->user_pass, 0, NVDIMM_PASSPHRASE_LEN);
		}

		/*
		 * CXL rev3 Table 8-118
		 * If user passphrase is not set or supported by device, current
		 * passphrase value is ignored. Will make the assumption that
		 * the operation will proceed as secure erase w/o passphrase
		 * since spec is not explicit.
		 */

		/* Scramble encryption keys so that data is effectively erased */
		break;
	default:
		return -EINVAL;
	}

	return 0;
}

static int mock_get_lsa(struct cxl_dev_state *cxlds, struct cxl_mbox_cmd *cmd)
{
	struct cxl_mbox_get_lsa *get_lsa = cmd->payload_in;
	struct cxl_mockmem_data *mdata = dev_get_drvdata(cxlds->dev);
	void *lsa = mdata->lsa;
	u32 offset, length;

	if (sizeof(*get_lsa) > cmd->size_in)
		return -EINVAL;
	offset = le32_to_cpu(get_lsa->offset);
	length = le32_to_cpu(get_lsa->length);
	if (offset + length > LSA_SIZE)
		return -EINVAL;
	if (length > cmd->size_out)
		return -EINVAL;

	memcpy(cmd->payload_out, lsa + offset, length);
	return 0;
}

static int mock_set_lsa(struct cxl_dev_state *cxlds, struct cxl_mbox_cmd *cmd)
{
	struct cxl_mbox_set_lsa *set_lsa = cmd->payload_in;
	struct cxl_mockmem_data *mdata = dev_get_drvdata(cxlds->dev);
	void *lsa = mdata->lsa;
	u32 offset, length;

	if (sizeof(*set_lsa) > cmd->size_in)
		return -EINVAL;
	offset = le32_to_cpu(set_lsa->offset);
	length = cmd->size_in - sizeof(*set_lsa);
	if (offset + length > LSA_SIZE)
		return -EINVAL;

	memcpy(lsa + offset, &set_lsa->data[0], length);
	return 0;
}

static int mock_health_info(struct cxl_dev_state *cxlds,
			    struct cxl_mbox_cmd *cmd)
{
	struct cxl_mbox_health_info health_info = {
		/* set flags for maint needed, perf degraded, hw replacement */
		.health_status = 0x7,
		/* set media status to "All Data Lost" */
		.media_status = 0x3,
		/*
		 * set ext_status flags for:
		 *  ext_life_used: normal,
		 *  ext_temperature: critical,
		 *  ext_corrected_volatile: warning,
		 *  ext_corrected_persistent: normal,
		 */
		.ext_status = 0x18,
		.life_used = 15,
		.temperature = cpu_to_le16(25),
		.dirty_shutdowns = cpu_to_le32(10),
		.volatile_errors = cpu_to_le32(20),
		.pmem_errors = cpu_to_le32(30),
	};

	if (cmd->size_out < sizeof(health_info))
		return -EINVAL;

	memcpy(cmd->payload_out, &health_info, sizeof(health_info));
	return 0;
}

static struct mock_poison {
	struct cxl_dev_state *cxlds;
	u64 dpa;
} mock_poison_list[MOCK_INJECT_TEST_MAX];

static struct cxl_mbox_poison_out *
cxl_get_injected_po(struct cxl_dev_state *cxlds, u64 offset, u64 length)
{
	struct cxl_mbox_poison_out *po;
	int nr_records = 0;
	u64 dpa;

	po = kzalloc(struct_size(po, record, poison_inject_dev_max), GFP_KERNEL);
	if (!po)
		return NULL;

	for (int i = 0; i < MOCK_INJECT_TEST_MAX; i++) {
		if (mock_poison_list[i].cxlds != cxlds)
			continue;
		if (mock_poison_list[i].dpa < offset ||
		    mock_poison_list[i].dpa > offset + length - 1)
			continue;

		dpa = mock_poison_list[i].dpa + CXL_POISON_SOURCE_INJECTED;
		po->record[nr_records].address = cpu_to_le64(dpa);
		po->record[nr_records].length = cpu_to_le32(1);
		nr_records++;
		if (nr_records == poison_inject_dev_max)
			break;
	}

	/* Always return count, even when zero */
	po->count = cpu_to_le16(nr_records);

	return po;
}

static int mock_get_poison(struct cxl_dev_state *cxlds,
			   struct cxl_mbox_cmd *cmd)
{
	struct cxl_mbox_poison_in *pi = cmd->payload_in;
	struct cxl_mbox_poison_out *po;
	u64 offset = le64_to_cpu(pi->offset);
	u64 length = le64_to_cpu(pi->length);
	int nr_records;

	po = cxl_get_injected_po(cxlds, offset, length);
	if (!po)
		return -ENOMEM;
	nr_records = le16_to_cpu(po->count);
	memcpy(cmd->payload_out, po, struct_size(po, record, nr_records));
	cmd->size_out = struct_size(po, record, nr_records);
	kfree(po);

	return 0;
}

static bool mock_poison_dev_max_injected(struct cxl_dev_state *cxlds)
{
	int count = 0;

	for (int i = 0; i < MOCK_INJECT_TEST_MAX; i++) {
		if (mock_poison_list[i].cxlds == cxlds)
			count++;
	}
	return (count >= poison_inject_dev_max);
}

static bool mock_poison_add(struct cxl_dev_state *cxlds, u64 dpa)
{
	if (mock_poison_dev_max_injected(cxlds)) {
		dev_dbg(cxlds->dev,
			"Device poison injection limit has been reached: %d\n",
			MOCK_INJECT_DEV_MAX);
		return false;
	}

	for (int i = 0; i < MOCK_INJECT_TEST_MAX; i++) {
		if (!mock_poison_list[i].cxlds) {
			mock_poison_list[i].cxlds = cxlds;
			mock_poison_list[i].dpa = dpa;
			return true;
		}
	}
	dev_dbg(cxlds->dev,
		"Mock test poison injection limit has been reached: %d\n",
		MOCK_INJECT_TEST_MAX);

	return false;
}

static bool mock_poison_found(struct cxl_dev_state *cxlds, u64 dpa)
{
	for (int i = 0; i < MOCK_INJECT_TEST_MAX; i++) {
		if (mock_poison_list[i].cxlds == cxlds &&
		    mock_poison_list[i].dpa == dpa)
			return true;
	}
	return false;
}

static int mock_inject_poison(struct cxl_dev_state *cxlds,
			      struct cxl_mbox_cmd *cmd)
{
	struct cxl_mbox_inject_poison *pi = cmd->payload_in;
	u64 dpa = le64_to_cpu(pi->address);

	if (mock_poison_found(cxlds, dpa)) {
		/* Not an error to inject poison if already poisoned */
		dev_dbg(cxlds->dev, "DPA: 0x%llx already poisoned\n", dpa);
		return 0;
	}
	if (!mock_poison_add(cxlds, dpa))
		return -ENXIO;

	return 0;
}

static bool mock_poison_del(struct cxl_dev_state *cxlds, u64 dpa)
{
	for (int i = 0; i < MOCK_INJECT_TEST_MAX; i++) {
		if (mock_poison_list[i].cxlds == cxlds &&
		    mock_poison_list[i].dpa == dpa) {
			mock_poison_list[i].cxlds = NULL;
			return true;
		}
	}
	return false;
}

static int mock_clear_poison(struct cxl_dev_state *cxlds,
			     struct cxl_mbox_cmd *cmd)
{
	struct cxl_mbox_clear_poison *pi = cmd->payload_in;
	u64 dpa = le64_to_cpu(pi->address);

	/*
	 * A real CXL device will write pi->write_data to the address
	 * being cleared. In this mock, just delete this address from
	 * the mock poison list.
	 */
	if (!mock_poison_del(cxlds, dpa))
		dev_dbg(cxlds->dev, "DPA: 0x%llx not in poison list\n", dpa);

	return 0;
}

static bool mock_poison_list_empty(void)
{
	for (int i = 0; i < MOCK_INJECT_TEST_MAX; i++) {
		if (mock_poison_list[i].cxlds)
			return false;
	}
	return true;
}

static ssize_t poison_inject_max_show(struct device_driver *drv, char *buf)
{
	return sysfs_emit(buf, "%u\n", poison_inject_dev_max);
}

static ssize_t poison_inject_max_store(struct device_driver *drv,
				       const char *buf, size_t len)
{
	int val;

	if (kstrtoint(buf, 0, &val) < 0)
		return -EINVAL;

	if (!mock_poison_list_empty())
		return -EBUSY;

	if (val <= MOCK_INJECT_TEST_MAX)
		poison_inject_dev_max = val;
	else
		return -EINVAL;

	return len;
}

static DRIVER_ATTR_RW(poison_inject_max);

static struct attribute *cxl_mock_mem_core_attrs[] = {
	&driver_attr_poison_inject_max.attr,
	NULL
};
ATTRIBUTE_GROUPS(cxl_mock_mem_core);

static int cxl_mock_mbox_send(struct cxl_dev_state *cxlds, struct cxl_mbox_cmd *cmd)
{
	struct device *dev = cxlds->dev;
	int rc = -EIO;

	switch (cmd->opcode) {
	case CXL_MBOX_OP_SET_TIMESTAMP:
		rc = mock_set_timestamp(cxlds, cmd);
		break;
	case CXL_MBOX_OP_GET_SUPPORTED_LOGS:
		rc = mock_gsl(cmd);
		break;
	case CXL_MBOX_OP_GET_LOG:
		rc = mock_get_log(cxlds, cmd);
		break;
	case CXL_MBOX_OP_IDENTIFY:
		if (cxlds->rcd)
			rc = mock_rcd_id(cxlds, cmd);
		else
			rc = mock_id(cxlds, cmd);
		break;
	case CXL_MBOX_OP_GET_LSA:
		rc = mock_get_lsa(cxlds, cmd);
		break;
	case CXL_MBOX_OP_GET_PARTITION_INFO:
		rc = mock_partition_info(cxlds, cmd);
		break;
	case CXL_MBOX_OP_GET_EVENT_RECORD:
		rc = mock_get_event(cxlds, cmd);
		break;
	case CXL_MBOX_OP_CLEAR_EVENT_RECORD:
		rc = mock_clear_event(cxlds, cmd);
		break;
	case CXL_MBOX_OP_SET_LSA:
		rc = mock_set_lsa(cxlds, cmd);
		break;
	case CXL_MBOX_OP_GET_HEALTH_INFO:
		rc = mock_health_info(cxlds, cmd);
		break;
	case CXL_MBOX_OP_GET_SECURITY_STATE:
		rc = mock_get_security_state(cxlds, cmd);
		break;
	case CXL_MBOX_OP_SET_PASSPHRASE:
		rc = mock_set_passphrase(cxlds, cmd);
		break;
	case CXL_MBOX_OP_DISABLE_PASSPHRASE:
		rc = mock_disable_passphrase(cxlds, cmd);
		break;
	case CXL_MBOX_OP_FREEZE_SECURITY:
		rc = mock_freeze_security(cxlds, cmd);
		break;
	case CXL_MBOX_OP_UNLOCK:
		rc = mock_unlock_security(cxlds, cmd);
		break;
	case CXL_MBOX_OP_PASSPHRASE_SECURE_ERASE:
		rc = mock_passphrase_secure_erase(cxlds, cmd);
		break;
	case CXL_MBOX_OP_GET_POISON:
		rc = mock_get_poison(cxlds, cmd);
		break;
	case CXL_MBOX_OP_INJECT_POISON:
		rc = mock_inject_poison(cxlds, cmd);
		break;
	case CXL_MBOX_OP_CLEAR_POISON:
		rc = mock_clear_poison(cxlds, cmd);
		break;
	default:
		break;
	}

	dev_dbg(dev, "opcode: %#x sz_in: %zd sz_out: %zd rc: %d\n", cmd->opcode,
		cmd->size_in, cmd->size_out, rc);

	return rc;
}

static void label_area_release(void *lsa)
{
	vfree(lsa);
}

static bool is_rcd(struct platform_device *pdev)
{
	const struct platform_device_id *id = platform_get_device_id(pdev);

	return !!id->driver_data;
}

static ssize_t event_trigger_store(struct device *dev,
				   struct device_attribute *attr,
				   const char *buf, size_t count)
{
	cxl_mock_event_trigger(dev);
	return count;
}
static DEVICE_ATTR_WO(event_trigger);

static int cxl_mock_mem_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct cxl_memdev *cxlmd;
	struct cxl_dev_state *cxlds;
	struct cxl_mockmem_data *mdata;
	int rc;

	mdata = devm_kzalloc(dev, sizeof(*mdata), GFP_KERNEL);
	if (!mdata)
		return -ENOMEM;
	dev_set_drvdata(dev, mdata);

	mdata->lsa = vmalloc(LSA_SIZE);
	if (!mdata->lsa)
		return -ENOMEM;
	rc = devm_add_action_or_reset(dev, label_area_release, mdata->lsa);
	if (rc)
		return rc;

	cxlds = cxl_dev_state_create(dev);
	if (IS_ERR(cxlds))
		return PTR_ERR(cxlds);

	cxlds->serial = pdev->id;
	cxlds->mbox_send = cxl_mock_mbox_send;
	cxlds->payload_size = SZ_4K;
	cxlds->event.buf = (struct cxl_get_event_payload *) mdata->event_buf;
	if (is_rcd(pdev)) {
		cxlds->rcd = true;
		cxlds->component_reg_phys = CXL_RESOURCE_NONE;
	}

	rc = cxl_enumerate_cmds(cxlds);
	if (rc)
		return rc;

	rc = cxl_poison_state_init(cxlds);
	if (rc)
		return rc;

	rc = cxl_set_timestamp(cxlds);
	if (rc)
		return rc;

	rc = cxl_dev_state_identify(cxlds);
	if (rc)
		return rc;

	rc = cxl_mem_create_range_info(cxlds);
	if (rc)
		return rc;

	mdata->mes.cxlds = cxlds;
	cxl_mock_add_event_logs(&mdata->mes);

	cxlmd = devm_cxl_add_memdev(cxlds);
	if (IS_ERR(cxlmd))
		return PTR_ERR(cxlmd);

	cxl_mem_get_event_records(cxlds, CXLDEV_EVENT_STATUS_ALL);

	return 0;
}

static ssize_t security_lock_show(struct device *dev,
				  struct device_attribute *attr, char *buf)
{
	struct cxl_mockmem_data *mdata = dev_get_drvdata(dev);

	return sysfs_emit(buf, "%u\n",
			  !!(mdata->security_state & CXL_PMEM_SEC_STATE_LOCKED));
}

static ssize_t security_lock_store(struct device *dev, struct device_attribute *attr,
				   const char *buf, size_t count)
{
	struct cxl_mockmem_data *mdata = dev_get_drvdata(dev);
	u32 mask = CXL_PMEM_SEC_STATE_FROZEN | CXL_PMEM_SEC_STATE_USER_PLIMIT |
		   CXL_PMEM_SEC_STATE_MASTER_PLIMIT;
	int val;

	if (kstrtoint(buf, 0, &val) < 0)
		return -EINVAL;

	if (val == 1) {
		if (!(mdata->security_state & CXL_PMEM_SEC_STATE_USER_PASS_SET))
			return -ENXIO;
		mdata->security_state |= CXL_PMEM_SEC_STATE_LOCKED;
		mdata->security_state &= ~mask;
	} else {
		return -EINVAL;
	}
	return count;
}

static DEVICE_ATTR_RW(security_lock);

static struct attribute *cxl_mock_mem_attrs[] = {
	&dev_attr_security_lock.attr,
	&dev_attr_event_trigger.attr,
	NULL
};
ATTRIBUTE_GROUPS(cxl_mock_mem);

static const struct platform_device_id cxl_mock_mem_ids[] = {
	{ .name = "cxl_mem", 0 },
	{ .name = "cxl_rcd", 1 },
	{ },
};
MODULE_DEVICE_TABLE(platform, cxl_mock_mem_ids);

static struct platform_driver cxl_mock_mem_driver = {
	.probe = cxl_mock_mem_probe,
	.id_table = cxl_mock_mem_ids,
	.driver = {
		.name = KBUILD_MODNAME,
		.dev_groups = cxl_mock_mem_groups,
		.groups = cxl_mock_mem_core_groups,
	},
};

module_platform_driver(cxl_mock_mem_driver);
MODULE_LICENSE("GPL v2");
MODULE_IMPORT_NS(CXL);