diff options
Diffstat (limited to 'drivers/soc/xilinx/xlnx_event_manager.c')
| -rw-r--r-- | drivers/soc/xilinx/xlnx_event_manager.c | 600 |
1 files changed, 600 insertions, 0 deletions
diff --git a/drivers/soc/xilinx/xlnx_event_manager.c b/drivers/soc/xilinx/xlnx_event_manager.c new file mode 100644 index 000000000000..b27f8853508e --- /dev/null +++ b/drivers/soc/xilinx/xlnx_event_manager.c @@ -0,0 +1,600 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Xilinx Event Management Driver + * + * Copyright (C) 2021 Xilinx, 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, cpu_number1); + +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 FIRMWARE_VERSION_MASK (0xFFFFU) +#define REGISTER_NOTIFIER_FIRMWARE_VERSION (2U) + +static DEFINE_HASHTABLE(reg_driver_map, REGISTERED_DRIVER_MAX_ORDER); +static int sgi_num = XLNX_EVENT_SGI_NUM; + +/** + * 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. + * @agent_data: Data passed back to handler function. + * @cb_type: Type of Api callback, like PM_NOTIFY_CB, etc. + * @eve_cb: Function pointer to store the callback function. + * @wake: If this flag set, firmware will wakeup processor if is + * in sleep or power down state. + * @hentry: hlist_node that hooks this entry into hashtable. + */ +struct registered_event_data { + u64 key; + enum pm_api_cb_id cb_type; + void *agent_data; + + event_cb_func_t eve_cb; + bool wake; + struct hlist_node hentry; +}; + +static bool xlnx_is_error_event(const u32 node_id) +{ + if (node_id == EVENT_ERROR_PMC_ERR1 || + node_id == EVENT_ERROR_PMC_ERR2 || + node_id == EVENT_ERROR_PSM_ERR1 || + node_id == EVENT_ERROR_PSM_ERR2) + 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; + struct registered_event_data *eve_data; + + 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) { + pr_err("Found as already registered\n"); + return -EINVAL; + } + } + + /* Add new entry if not present */ + eve_data = kmalloc(sizeof(*eve_data), GFP_KERNEL); + if (!eve_data) + return -ENOMEM; + + eve_data->key = key; + eve_data->cb_type = PM_NOTIFY_CB; + eve_data->eve_cb = cb_fun; + eve_data->wake = wake; + eve_data->agent_data = data; + + hash_add(reg_driver_map, &eve_data->hentry, key); + + return 0; +} + +static int xlnx_add_cb_for_suspend(event_cb_func_t cb_fun, void *data) +{ + struct registered_event_data *eve_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(sizeof(*eve_data), GFP_KERNEL); + if (!eve_data) + return -ENOMEM; + + eve_data->key = 0; + eve_data->cb_type = PM_INIT_SUSPEND_CB; + eve_data->eve_cb = cb_fun; + eve_data->agent_data = data; + + 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; + + /* 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 && + eve_data->eve_cb == cb_fun) { + is_callback_found = true; + /* remove an object from a hashtable */ + hash_del(&eve_data->hentry); + kfree(eve_data); + } + } + 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) +{ + bool is_callback_found = false; + struct registered_event_data *eve_data; + u64 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 && + eve_data->eve_cb == cb_fun) { + is_callback_found = true; + /* remove an object from a hashtable */ + hash_del(&eve_data->hentry); + kfree(eve_data); + } + } + 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); + } + } + } + + 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); + } + } else { + xlnx_remove_cb_for_notify_event(node_id, event, cb_fun); + } + 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. + * + * 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) +{ + int ret; + u32 eve, 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_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); + } 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); + } + } + + /* 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]; + + /* 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) { + eve_data->eve_cb(&payload[0], eve_data->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; + + /* 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) { + eve_data->eve_cb(&payload[0], eve_data->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); + /* Remove already registered event from hash table */ + xlnx_remove_cb_for_notify_event(payload[1], payload[2], + eve_data->eve_cb); + } + } + } + if (!is_callback_found) + pr_warn("Didn't find any registered callback for 0x%x 0x%x\n", + payload[1], payload[2]); +} + +static void xlnx_get_event_callback_data(u32 *buf) +{ + zynqmp_pm_invoke_fn(GET_CALLBACK_DATA, 0, 0, 0, 0, buf); +} + +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; + int cpu = smp_processor_id(); + /* + * 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); + + per_cpu(cpu_number1, cpu) = cpu; + ret = request_percpu_irq(virq_sgi, xlnx_event_handler, "xlnx_event_mgmt", + &cpu_number1); + 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) +{ + int cpu = smp_processor_id(); + + per_cpu(cpu_number1, cpu) = cpu; + + 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, &cpu_number1); + 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_invoke_fn(PM_IOCTL, 0, IOCTL_REGISTER_SGI, sgi_num, + 0, NULL); + if (ret) { + dev_err(&pdev->dev, "SGI %d Registration over TF-A failed with %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 int xlnx_event_manager_remove(struct platform_device *pdev) +{ + int i; + struct registered_event_data *eve_data; + struct hlist_node *tmp; + int ret; + + hash_for_each_safe(reg_driver_map, i, tmp, eve_data, hentry) { + hash_del(&eve_data->hentry); + kfree(eve_data); + } + + ret = zynqmp_pm_invoke_fn(PM_IOCTL, 0, IOCTL_REGISTER_SGI, 0, 1, NULL); + 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; + + return ret; +} + +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); |