blob: b27f8853508ec4d965ad8cff91afdcf53fae5e87 [file] [log] [blame]
// 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);