// SPDX-License-Identifier: GPL-2.0
/*
 * Xilinx Event Management Driver
 *
 *  Copyright (C) 2021 Xilinx, Inc.
 *  Copyright (C) 2024 Advanced Micro Devices, Inc.
 *
 *  Abhyuday Godhasara <abhyuday.godhasara@xilinx.com>
 */

#include <linux/cpuhotplug.h>
#include <linux/firmware/xlnx-event-manager.h>
#include <linux/firmware/xlnx-zynqmp.h>
#include <linux/hashtable.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/irqdomain.h>
#include <linux/module.h>
#include <linux/of_irq.h>
#include <linux/platform_device.h>
#include <linux/slab.h>

static DEFINE_PER_CPU_READ_MOSTLY(int, dummy_cpu_number);

static int virq_sgi;
static int event_manager_availability = -EACCES;

/* SGI number used for Event management driver */
#define XLNX_EVENT_SGI_NUM      (15)

/* Max number of driver can register for same event */
#define MAX_DRIVER_PER_EVENT    (10U)

/* Max HashMap Order for PM API feature check (1<<7 = 128) */
#define REGISTERED_DRIVER_MAX_ORDER     (7)

#define MAX_BITS        (32U) /* Number of bits available for error mask */

#define REGISTER_NOTIFIER_FIRMWARE_VERSION      (2U)

static DEFINE_HASHTABLE(reg_driver_map, REGISTERED_DRIVER_MAX_ORDER);
static int sgi_num = XLNX_EVENT_SGI_NUM;

static bool is_need_to_unregister;

/**
 * struct agent_cb - Registered callback function and private data.
 * @agent_data:         Data passed back to handler function.
 * @eve_cb:             Function pointer to store the callback function.
 * @list:               member to create list.
 */
struct agent_cb {
        void *agent_data;
        event_cb_func_t eve_cb;
        struct list_head list;
};

/**
 * struct registered_event_data - Registered Event Data.
 * @key:                key is the combine id(Node-Id | Event-Id) of type u64
 *                      where upper u32 for Node-Id and lower u32 for Event-Id,
 *                      And this used as key to index into hashmap.
 * @cb_type:            Type of Api callback, like PM_NOTIFY_CB, etc.
 * @wake:               If this flag set, firmware will wake up processor if is
 *                      in sleep or power down state.
 * @cb_list_head:       Head of call back data list which contain the information
 *                      about registered handler and private data.
 * @hentry:             hlist_node that hooks this entry into hashtable.
 */
struct registered_event_data {
        u64 key;
        enum pm_api_cb_id cb_type;
        bool wake;
        struct list_head cb_list_head;
        struct hlist_node hentry;
};

static bool xlnx_is_error_event(const u32 node_id)
{
        u32 pm_family_code;

        zynqmp_pm_get_family_info(&pm_family_code);

        if (pm_family_code == PM_VERSAL_FAMILY_CODE) {
                if (node_id == VERSAL_EVENT_ERROR_PMC_ERR1 ||
                    node_id == VERSAL_EVENT_ERROR_PMC_ERR2 ||
                    node_id == VERSAL_EVENT_ERROR_PSM_ERR1 ||
                    node_id == VERSAL_EVENT_ERROR_PSM_ERR2)
                        return true;
        } else if (pm_family_code == PM_VERSAL_NET_FAMILY_CODE) {
                if (node_id == VERSAL_NET_EVENT_ERROR_PMC_ERR1 ||
                    node_id == VERSAL_NET_EVENT_ERROR_PMC_ERR2 ||
                    node_id == VERSAL_NET_EVENT_ERROR_PMC_ERR3 ||
                    node_id == VERSAL_NET_EVENT_ERROR_PSM_ERR1 ||
                    node_id == VERSAL_NET_EVENT_ERROR_PSM_ERR2 ||
                    node_id == VERSAL_NET_EVENT_ERROR_PSM_ERR3 ||
                    node_id == VERSAL_NET_EVENT_ERROR_PSM_ERR4)
                        return true;
        }

        return false;
}

static int xlnx_add_cb_for_notify_event(const u32 node_id, const u32 event, const bool wake,
                                        event_cb_func_t cb_fun, void *data)
{
        u64 key = 0;
        bool present_in_hash = false;
        struct registered_event_data *eve_data;
        struct agent_cb *cb_data;
        struct agent_cb *cb_pos;
        struct agent_cb *cb_next;

        key = ((u64)node_id << 32U) | (u64)event;
        /* Check for existing entry in hash table for given key id */
        hash_for_each_possible(reg_driver_map, eve_data, hentry, key) {
                if (eve_data->key == key) {
                        present_in_hash = true;
                        break;
                }
        }

        if (!present_in_hash) {
                /* Add new entry if not present in HASH table */
                eve_data = kmalloc_obj(*eve_data);
                if (!eve_data)
                        return -ENOMEM;
                eve_data->key = key;
                eve_data->cb_type = PM_NOTIFY_CB;
                eve_data->wake = wake;
                INIT_LIST_HEAD(&eve_data->cb_list_head);

                cb_data = kmalloc_obj(*cb_data);
                if (!cb_data) {
                        kfree(eve_data);
                        return -ENOMEM;
                }
                cb_data->eve_cb = cb_fun;
                cb_data->agent_data = data;

                /* Add into callback list */
                list_add(&cb_data->list, &eve_data->cb_list_head);

                /* Add into HASH table */
                hash_add(reg_driver_map, &eve_data->hentry, key);
        } else {
                /* Search for callback function and private data in list */
                list_for_each_entry_safe(cb_pos, cb_next, &eve_data->cb_list_head, list) {
                        if (cb_pos->eve_cb == cb_fun &&
                            cb_pos->agent_data == data) {
                                return 0;
                        }
                }

                /* Add multiple handler and private data in list */
                cb_data = kmalloc_obj(*cb_data);
                if (!cb_data)
                        return -ENOMEM;
                cb_data->eve_cb = cb_fun;
                cb_data->agent_data = data;

                list_add(&cb_data->list, &eve_data->cb_list_head);
        }

        return 0;
}

static int xlnx_add_cb_for_suspend(event_cb_func_t cb_fun, void *data)
{
        struct registered_event_data *eve_data;
        struct agent_cb *cb_data;

        /* Check for existing entry in hash table for given cb_type */
        hash_for_each_possible(reg_driver_map, eve_data, hentry, PM_INIT_SUSPEND_CB) {
                if (eve_data->cb_type == PM_INIT_SUSPEND_CB) {
                        pr_err("Found as already registered\n");
                        return -EINVAL;
                }
        }

        /* Add new entry if not present */
        eve_data = kmalloc_obj(*eve_data);
        if (!eve_data)
                return -ENOMEM;

        eve_data->key = 0;
        eve_data->cb_type = PM_INIT_SUSPEND_CB;
        INIT_LIST_HEAD(&eve_data->cb_list_head);

        cb_data = kmalloc_obj(*cb_data);
        if (!cb_data) {
                kfree(eve_data);
                return -ENOMEM;
        }
        cb_data->eve_cb = cb_fun;
        cb_data->agent_data = data;

        /* Add into callback list */
        list_add(&cb_data->list, &eve_data->cb_list_head);

        hash_add(reg_driver_map, &eve_data->hentry, PM_INIT_SUSPEND_CB);

        return 0;
}

static int xlnx_remove_cb_for_suspend(event_cb_func_t cb_fun)
{
        bool is_callback_found = false;
        struct registered_event_data *eve_data;
        struct agent_cb *cb_pos;
        struct agent_cb *cb_next;
        struct hlist_node *tmp;

        is_need_to_unregister = false;

        /* Check for existing entry in hash table for given cb_type */
        hash_for_each_possible_safe(reg_driver_map, eve_data, tmp, hentry, PM_INIT_SUSPEND_CB) {
                if (eve_data->cb_type == PM_INIT_SUSPEND_CB) {
                        /* Delete the list of callback */
                        list_for_each_entry_safe(cb_pos, cb_next, &eve_data->cb_list_head, list) {
                                if (cb_pos->eve_cb == cb_fun) {
                                        is_callback_found = true;
                                        list_del_init(&cb_pos->list);
                                        kfree(cb_pos);
                                }
                        }
                        /* remove an object from a hashtable */
                        hash_del(&eve_data->hentry);
                        kfree(eve_data);
                        is_need_to_unregister = true;
                }
        }
        if (!is_callback_found) {
                pr_warn("Didn't find any registered callback for suspend event\n");
                return -EINVAL;
        }

        return 0;
}

static int xlnx_remove_cb_for_notify_event(const u32 node_id, const u32 event,
                                           event_cb_func_t cb_fun, void *data)
{
        bool is_callback_found = false;
        struct registered_event_data *eve_data;
        u64 key = ((u64)node_id << 32U) | (u64)event;
        struct agent_cb *cb_pos;
        struct agent_cb *cb_next;
        struct hlist_node *tmp;

        is_need_to_unregister = false;

        /* Check for existing entry in hash table for given key id */
        hash_for_each_possible_safe(reg_driver_map, eve_data, tmp, hentry, key) {
                if (eve_data->key == key) {
                        /* Delete the list of callback */
                        list_for_each_entry_safe(cb_pos, cb_next, &eve_data->cb_list_head, list) {
                                if (cb_pos->eve_cb == cb_fun &&
                                    cb_pos->agent_data == data) {
                                        is_callback_found = true;
                                        list_del_init(&cb_pos->list);
                                        kfree(cb_pos);
                                }
                        }

                        /* Remove HASH table if callback list is empty */
                        if (list_empty(&eve_data->cb_list_head)) {
                                /* remove an object from a HASH table */
                                hash_del(&eve_data->hentry);
                                kfree(eve_data);
                                is_need_to_unregister = true;
                        }
                }
        }
        if (!is_callback_found) {
                pr_warn("Didn't find any registered callback for 0x%x 0x%x\n",
                        node_id, event);
                return -EINVAL;
        }

        return 0;
}

/**
 * xlnx_register_event() - Register for the event.
 * @cb_type:    Type of callback from pm_api_cb_id,
 *                      PM_NOTIFY_CB - for Error Events,
 *                      PM_INIT_SUSPEND_CB - for suspend callback.
 * @node_id:    Node-Id related to event.
 * @event:      Event Mask for the Error Event.
 * @wake:       Flag specifying whether the subsystem should be woken upon
 *              event notification.
 * @cb_fun:     Function pointer to store the callback function.
 * @data:       Pointer for the driver instance.
 *
 * Return:      Returns 0 on successful registration else error code.
 */
int xlnx_register_event(const enum pm_api_cb_id cb_type, const u32 node_id, const u32 event,
                        const bool wake, event_cb_func_t cb_fun, void *data)
{
        int ret = 0;
        u32 eve;
        int pos;

        if (event_manager_availability)
                return event_manager_availability;

        if (cb_type != PM_NOTIFY_CB && cb_type != PM_INIT_SUSPEND_CB) {
                pr_err("%s() Unsupported Callback 0x%x\n", __func__, cb_type);
                return -EINVAL;
        }

        if (!cb_fun)
                return -EFAULT;

        if (cb_type == PM_INIT_SUSPEND_CB) {
                ret = xlnx_add_cb_for_suspend(cb_fun, data);
        } else {
                if (!xlnx_is_error_event(node_id)) {
                        /* Add entry for Node-Id/Event in hash table */
                        ret = xlnx_add_cb_for_notify_event(node_id, event, wake, cb_fun, data);
                } else {
                        /* Add into Hash table */
                        for (pos = 0; pos < MAX_BITS; pos++) {
                                eve = event & (1 << pos);
                                if (!eve)
                                        continue;

                                /* Add entry for Node-Id/Eve in hash table */
                                ret = xlnx_add_cb_for_notify_event(node_id, eve, wake, cb_fun,
                                                                   data);
                                /* Break the loop if got error */
                                if (ret)
                                        break;
                        }
                        if (ret) {
                                /* Skip the Event for which got the error */
                                pos--;
                                /* Remove registered(during this call) event from hash table */
                                for ( ; pos >= 0; pos--) {
                                        eve = event & (1 << pos);
                                        if (!eve)
                                                continue;
                                        xlnx_remove_cb_for_notify_event(node_id, eve, cb_fun, data);
                                }
                        }
                }

                if (ret) {
                        pr_err("%s() failed for 0x%x and 0x%x: %d\r\n", __func__, node_id,
                               event, ret);
                        return ret;
                }

                /* Register for Node-Id/Event combination in firmware */
                ret = zynqmp_pm_register_notifier(node_id, event, wake, true);
                if (ret) {
                        pr_err("%s() failed for 0x%x and 0x%x: %d\r\n", __func__, node_id,
                               event, ret);
                        /* Remove already registered event from hash table */
                        if (xlnx_is_error_event(node_id)) {
                                for (pos = 0; pos < MAX_BITS; pos++) {
                                        eve = event & (1 << pos);
                                        if (!eve)
                                                continue;
                                        xlnx_remove_cb_for_notify_event(node_id, eve, cb_fun, data);
                                }
                        } else {
                                xlnx_remove_cb_for_notify_event(node_id, event, cb_fun, data);
                        }
                        return ret;
                }
        }

        return ret;
}
EXPORT_SYMBOL_GPL(xlnx_register_event);

/**
 * xlnx_unregister_event() - Unregister for the event.
 * @cb_type:    Type of callback from pm_api_cb_id,
 *                      PM_NOTIFY_CB - for Error Events,
 *                      PM_INIT_SUSPEND_CB - for suspend callback.
 * @node_id:    Node-Id related to event.
 * @event:      Event Mask for the Error Event.
 * @cb_fun:     Function pointer of callback function.
 * @data:       Pointer of agent's private data.
 *
 * Return:      Returns 0 on successful unregistration else error code.
 */
int xlnx_unregister_event(const enum pm_api_cb_id cb_type, const u32 node_id, const u32 event,
                          event_cb_func_t cb_fun, void *data)
{
        int ret = 0;
        u32 eve, pos;

        is_need_to_unregister = false;

        if (event_manager_availability)
                return event_manager_availability;

        if (cb_type != PM_NOTIFY_CB && cb_type != PM_INIT_SUSPEND_CB) {
                pr_err("%s() Unsupported Callback 0x%x\n", __func__, cb_type);
                return -EINVAL;
        }

        if (!cb_fun)
                return -EFAULT;

        if (cb_type == PM_INIT_SUSPEND_CB) {
                ret = xlnx_remove_cb_for_suspend(cb_fun);
        } else {
                /* Remove Node-Id/Event from hash table */
                if (!xlnx_is_error_event(node_id)) {
                        xlnx_remove_cb_for_notify_event(node_id, event, cb_fun, data);
                } else {
                        for (pos = 0; pos < MAX_BITS; pos++) {
                                eve = event & (1 << pos);
                                if (!eve)
                                        continue;

                                xlnx_remove_cb_for_notify_event(node_id, eve, cb_fun, data);
                        }
                }

                /* Un-register if list is empty */
                if (is_need_to_unregister) {
                        /* Un-register for Node-Id/Event combination */
                        ret = zynqmp_pm_register_notifier(node_id, event, false, false);
                        if (ret) {
                                pr_err("%s() failed for 0x%x and 0x%x: %d\n",
                                       __func__, node_id, event, ret);
                                return ret;
                        }
                }
        }

        return ret;
}
EXPORT_SYMBOL_GPL(xlnx_unregister_event);

static void xlnx_call_suspend_cb_handler(const u32 *payload)
{
        bool is_callback_found = false;
        struct registered_event_data *eve_data;
        u32 cb_type = payload[0];
        struct agent_cb *cb_pos;
        struct agent_cb *cb_next;

        /* Check for existing entry in hash table for given cb_type */
        hash_for_each_possible(reg_driver_map, eve_data, hentry, cb_type) {
                if (eve_data->cb_type == cb_type) {
                        list_for_each_entry_safe(cb_pos, cb_next, &eve_data->cb_list_head, list) {
                                cb_pos->eve_cb(&payload[0], cb_pos->agent_data);
                                is_callback_found = true;
                        }
                }
        }
        if (!is_callback_found)
                pr_warn("Didn't find any registered callback for suspend event\n");
}

static void xlnx_call_notify_cb_handler(const u32 *payload)
{
        bool is_callback_found = false;
        struct registered_event_data *eve_data;
        u64 key = ((u64)payload[1] << 32U) | (u64)payload[2];
        int ret;
        struct agent_cb *cb_pos;
        struct agent_cb *cb_next;

        /* Check for existing entry in hash table for given key id */
        hash_for_each_possible(reg_driver_map, eve_data, hentry, key) {
                if (eve_data->key == key) {
                        list_for_each_entry_safe(cb_pos, cb_next, &eve_data->cb_list_head, list) {
                                cb_pos->eve_cb(&payload[0], cb_pos->agent_data);
                                is_callback_found = true;
                        }

                        /* re register with firmware to get future events */
                        ret = zynqmp_pm_register_notifier(payload[1], payload[2],
                                                          eve_data->wake, true);
                        if (ret) {
                                pr_err("%s() failed for 0x%x and 0x%x: %d\r\n", __func__,
                                       payload[1], payload[2], ret);
                                list_for_each_entry_safe(cb_pos, cb_next, &eve_data->cb_list_head,
                                                         list) {
                                        /* Remove already registered event from hash table */
                                        xlnx_remove_cb_for_notify_event(payload[1], payload[2],
                                                                        cb_pos->eve_cb,
                                                                        cb_pos->agent_data);
                                }
                        }
                }
        }
        if (!is_callback_found)
                pr_warn("Unhandled SGI node 0x%x event 0x%x. Expected with Xen hypervisor\n",
                        payload[1], payload[2]);
}

static void xlnx_get_event_callback_data(u32 *buf)
{
        zynqmp_pm_invoke_fn(GET_CALLBACK_DATA, buf, 0);
}

static irqreturn_t xlnx_event_handler(int irq, void *dev_id)
{
        u32 cb_type, node_id, event, pos;
        u32 payload[CB_MAX_PAYLOAD_SIZE] = {0};
        u32 event_data[CB_MAX_PAYLOAD_SIZE] = {0};

        /* Get event data */
        xlnx_get_event_callback_data(payload);

        /* First element is callback type, others are callback arguments */
        cb_type = payload[0];

        if (cb_type == PM_NOTIFY_CB) {
                node_id = payload[1];
                event = payload[2];
                if (!xlnx_is_error_event(node_id)) {
                        xlnx_call_notify_cb_handler(payload);
                } else {
                        /*
                         * Each call back function expecting payload as an input arguments.
                         * We can get multiple error events as in one call back through error
                         * mask. So payload[2] may can contain multiple error events.
                         * In reg_driver_map database we store data in the combination of single
                         * node_id-error combination.
                         * So coping the payload message into event_data and update the
                         * event_data[2] with Error Mask for single error event and use
                         * event_data as input argument for registered call back function.
                         *
                         */
                        memcpy(event_data, payload, (4 * CB_MAX_PAYLOAD_SIZE));
                        /* Support Multiple Error Event */
                        for (pos = 0; pos < MAX_BITS; pos++) {
                                if ((0 == (event & (1 << pos))))
                                        continue;
                                event_data[2] = (event & (1 << pos));
                                xlnx_call_notify_cb_handler(event_data);
                        }
                }
        } else if (cb_type == PM_INIT_SUSPEND_CB) {
                xlnx_call_suspend_cb_handler(payload);
        } else {
                pr_err("%s() Unsupported Callback %d\n", __func__, cb_type);
        }

        return IRQ_HANDLED;
}

static int xlnx_event_cpuhp_start(unsigned int cpu)
{
        enable_percpu_irq(virq_sgi, IRQ_TYPE_NONE);

        return 0;
}

static int xlnx_event_cpuhp_down(unsigned int cpu)
{
        disable_percpu_irq(virq_sgi);

        return 0;
}

static void xlnx_disable_percpu_irq(void *data)
{
        disable_percpu_irq(virq_sgi);
}

static int xlnx_event_init_sgi(struct platform_device *pdev)
{
        int ret = 0;
        /*
         * IRQ related structures are used for the following:
         * for each SGI interrupt ensure its mapped by GIC IRQ domain
         * and that each corresponding linux IRQ for the HW IRQ has
         * a handler for when receiving an interrupt from the remote
         * processor.
         */
        struct irq_domain *domain;
        struct irq_fwspec sgi_fwspec;
        struct device_node *interrupt_parent = NULL;
        struct device *parent = pdev->dev.parent;

        /* Find GIC controller to map SGIs. */
        interrupt_parent = of_irq_find_parent(parent->of_node);
        if (!interrupt_parent) {
                dev_err(&pdev->dev, "Failed to find property for Interrupt parent\n");
                return -EINVAL;
        }

        /* Each SGI needs to be associated with GIC's IRQ domain. */
        domain = irq_find_host(interrupt_parent);
        of_node_put(interrupt_parent);

        /* Each mapping needs GIC domain when finding IRQ mapping. */
        sgi_fwspec.fwnode = domain->fwnode;

        /*
         * When irq domain looks at mapping each arg is as follows:
         * 3 args for: interrupt type (SGI), interrupt # (set later), type
         */
        sgi_fwspec.param_count = 1;

        /* Set SGI's hwirq */
        sgi_fwspec.param[0] = sgi_num;
        virq_sgi = irq_create_fwspec_mapping(&sgi_fwspec);

        ret = request_percpu_irq(virq_sgi, xlnx_event_handler, "xlnx_event_mgmt",
                                 &dummy_cpu_number);

        WARN_ON(ret);
        if (ret) {
                irq_dispose_mapping(virq_sgi);
                return ret;
        }

        irq_to_desc(virq_sgi);
        irq_set_status_flags(virq_sgi, IRQ_PER_CPU);

        return ret;
}

static void xlnx_event_cleanup_sgi(struct platform_device *pdev)
{
        cpuhp_remove_state(CPUHP_AP_ONLINE_DYN);

        on_each_cpu(xlnx_disable_percpu_irq, NULL, 1);

        irq_clear_status_flags(virq_sgi, IRQ_PER_CPU);
        free_percpu_irq(virq_sgi, &dummy_cpu_number);
        irq_dispose_mapping(virq_sgi);
}

static int xlnx_event_manager_probe(struct platform_device *pdev)
{
        int ret;

        ret = zynqmp_pm_feature(PM_REGISTER_NOTIFIER);
        if (ret < 0) {
                dev_err(&pdev->dev, "Feature check failed with %d\n", ret);
                return ret;
        }

        if ((ret & FIRMWARE_VERSION_MASK) <
            REGISTER_NOTIFIER_FIRMWARE_VERSION) {
                dev_err(&pdev->dev, "Register notifier version error. Expected Firmware: v%d - Found: v%d\n",
                        REGISTER_NOTIFIER_FIRMWARE_VERSION,
                        ret & FIRMWARE_VERSION_MASK);
                return -EOPNOTSUPP;
        }

        /* Initialize the SGI */
        ret = xlnx_event_init_sgi(pdev);
        if (ret) {
                dev_err(&pdev->dev, "SGI Init has been failed with %d\n", ret);
                return ret;
        }

        /* Setup function for the CPU hot-plug cases */
        cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "soc/event:starting",
                          xlnx_event_cpuhp_start, xlnx_event_cpuhp_down);

        ret = zynqmp_pm_register_sgi(sgi_num, 0);
        if (ret) {
                if (ret == -EOPNOTSUPP)
                        dev_err(&pdev->dev, "SGI registration not supported by TF-A or Xen\n");
                else
                        dev_err(&pdev->dev, "SGI %d registration failed, err %d\n", sgi_num, ret);

                xlnx_event_cleanup_sgi(pdev);
                return ret;
        }

        event_manager_availability = 0;

        dev_info(&pdev->dev, "SGI %d Registered over TF-A\n", sgi_num);
        dev_info(&pdev->dev, "Xilinx Event Management driver probed\n");

        return ret;
}

static void xlnx_event_manager_remove(struct platform_device *pdev)
{
        int i;
        struct registered_event_data *eve_data;
        struct hlist_node *tmp;
        int ret;
        struct agent_cb *cb_pos;
        struct agent_cb *cb_next;

        hash_for_each_safe(reg_driver_map, i, tmp, eve_data, hentry) {
                list_for_each_entry_safe(cb_pos, cb_next, &eve_data->cb_list_head, list) {
                        list_del_init(&cb_pos->list);
                        kfree(cb_pos);
                }
                hash_del(&eve_data->hentry);
                kfree(eve_data);
        }

        ret = zynqmp_pm_register_sgi(0, 1);
        if (ret)
                dev_err(&pdev->dev, "SGI unregistration over TF-A failed with %d\n", ret);

        xlnx_event_cleanup_sgi(pdev);

        event_manager_availability = -EACCES;
}

static struct platform_driver xlnx_event_manager_driver = {
        .probe = xlnx_event_manager_probe,
        .remove = xlnx_event_manager_remove,
        .driver = {
                .name = "xlnx_event_manager",
        },
};
module_param(sgi_num, uint, 0);
module_platform_driver(xlnx_event_manager_driver);