// SPDX-License-Identifier: GPL-2.0
/*
* ZynqMP Generic PM domain support
*
* Copyright (C) 2015-2018 Xilinx, Inc.
*
* Davorin Mista <davorin.mista@aggios.com>
* Jolly Shah <jollys@xilinx.com>
* Rajan Vaja <rajan.vaja@xilinx.com>
*/
#include <linux/err.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/pm_domain.h>
#include <linux/slab.h>
#include <linux/firmware/xlnx-zynqmp.h>
#define ZYNQMP_NUM_DOMAINS (100)
/* Flag stating if PM nodes mapped to the PM domain has been requested */
#define ZYNQMP_PM_DOMAIN_REQUESTED BIT(0)
static const struct zynqmp_eemi_ops *eemi_ops;
/**
* struct zynqmp_pm_domain - Wrapper around struct generic_pm_domain
* @gpd: Generic power domain
* @node_id: PM node ID corresponding to device inside PM domain
* @flags: ZynqMP PM domain flags
*/
struct zynqmp_pm_domain {
struct generic_pm_domain gpd;
u32 node_id;
u8 flags;
};
/**
* zynqmp_gpd_is_active_wakeup_path() - Check if device is in wakeup source
* path
* @dev: Device to check for wakeup source path
* @not_used: Data member (not required)
*
* This function is checks device's child hierarchy and checks if any device is
* set as wakeup source.
*
* Return: 1 if device is in wakeup source path else 0
*/
static int zynqmp_gpd_is_active_wakeup_path(struct device *dev, void *not_used)
{
int may_wakeup;
may_wakeup = device_may_wakeup(dev);
if (may_wakeup)
return may_wakeup;
return device_for_each_child(dev, NULL,
zynqmp_gpd_is_active_wakeup_path);
}
/**
* zynqmp_gpd_power_on() - Power on PM domain
* @domain: Generic PM domain
*
* This function is called before devices inside a PM domain are resumed, to
* power on PM domain.
*
* Return: 0 on success, error code otherwise
*/
static int zynqmp_gpd_power_on(struct generic_pm_domain *domain)
{
int ret;
struct zynqmp_pm_domain *pd;
if (!eemi_ops->set_requirement)
return -ENXIO;
pd = container_of(domain, struct zynqmp_pm_domain, gpd);
ret = eemi_ops->set_requirement(pd->node_id,
ZYNQMP_PM_CAPABILITY_ACCESS,
ZYNQMP_PM_MAX_QOS,
ZYNQMP_PM_REQUEST_ACK_BLOCKING);
if (ret) {
pr_err("%s() %s set requirement for node %d failed: %d\n",
__func__, domain->name, pd->node_id, ret);
return ret;
}
pr_debug("%s() Powered on %s domain\n", __func__, domain->name);
return 0;
}
/**
* zynqmp_gpd_power_off() - Power off PM domain
* @domain: Generic PM domain
*
* This function is called after devices inside a PM domain are suspended, to
* power off PM domain.
*
* Return: 0 on success, error code otherwise
*/
static int zynqmp_gpd_power_off(struct generic_pm_domain *domain)
{
int ret;
struct pm_domain_data *pdd, *tmp;
struct zynqmp_pm_domain *pd;
u32 capabilities = 0;
bool may_wakeup;
if (!eemi_ops->set_requirement)
return -ENXIO;
pd = container_of(domain, struct zynqmp_pm_domain, gpd);
/* If domain is already released there is nothing to be done */
if (!(pd->flags & ZYNQMP_PM_DOMAIN_REQUESTED)) {
pr_debug("%s() %s domain is already released\n",
__func__, domain->name);
return 0;
}
list_for_each_entry_safe(pdd, tmp, &domain->dev_list, list_node) {
/* If device is in wakeup path, set capability to WAKEUP */
may_wakeup = zynqmp_gpd_is_active_wakeup_path(pdd->dev, NULL);
if (may_wakeup) {
dev_dbg(pdd->dev, "device is in wakeup path in %s\n",
domain->name);
capabilities = ZYNQMP_PM_CAPABILITY_WAKEUP;
break;
}
}
ret = eemi_ops->set_requirement(pd->node_id, capabilities, 0,
ZYNQMP_PM_REQUEST_ACK_NO);
/**
* If powering down of any node inside this domain fails,
* report and return the error
*/
if (ret) {
pr_err("%s() %s set requirement for node %d failed: %d\n",
__func__, domain->name, pd->node_id, ret);
return ret;
}
pr_debug("%s() Powered off %s domain\n", __func__, domain->name);
return 0;
}
/**
* zynqmp_gpd_attach_dev() - Attach device to the PM domain
* @domain: Generic PM domain
* @dev: Device to attach
*
* Return: 0 on success, error code otherwise
*/
static int zynqmp_gpd_attach_dev(struct generic_pm_domain *domain,
struct device *dev)
{
int ret;
struct zynqmp_pm_domain *pd;
if (!eemi_ops->request_node)
return -ENXIO;
pd = container_of(domain, struct zynqmp_pm_domain, gpd);
/* If this is not the first device to attach there is nothing to do */
if (domain->device_count)
return 0;
ret = eemi_ops->request_node(pd->node_id, 0, 0,
ZYNQMP_PM_REQUEST_ACK_BLOCKING);
/* If requesting a node fails print and return the error */
if (ret) {
pr_err("%s() %s request failed for node %d: %d\n",
__func__, domain->name, pd->node_id, ret);
return ret;
}
pd->flags |= ZYNQMP_PM_DOMAIN_REQUESTED;
pr_debug("%s() %s attached to %s domain\n", __func__,
dev_name(dev), domain->name);
return 0;
}
/**
* zynqmp_gpd_detach_dev() - Detach device from the PM domain
* @domain: Generic PM domain
* @dev: Device to detach
*/
static void zynqmp_gpd_detach_dev(struct generic_pm_domain *domain,
struct device *dev)
{
int ret;
struct zynqmp_pm_domain *pd;
if (!eemi_ops->release_node)
return;
pd = container_of(domain, struct zynqmp_pm_domain, gpd);
/* If this is not the last device to detach there is nothing to do */
if (domain->device_count)
return;
ret = eemi_ops->release_node(pd->node_id);
/* If releasing a node fails print the error and return */
if (ret) {
pr_err("%s() %s release failed for node %d: %d\n",
__func__, domain->name, pd->node_id, ret);
return;
}
pd->flags &= ~ZYNQMP_PM_DOMAIN_REQUESTED;
pr_debug("%s() %s detached from %s domain\n", __func__,
dev_name(dev), domain->name);
}
static struct generic_pm_domain *zynqmp_gpd_xlate
(struct of_phandle_args *genpdspec, void *data)
{
struct genpd_onecell_data *genpd_data = data;
unsigned int i, idx = genpdspec->args[0];
struct zynqmp_pm_domain *pd;
pd = container_of(genpd_data->domains[0], struct zynqmp_pm_domain, gpd);
if (genpdspec->args_count != 1)
return ERR_PTR(-EINVAL);
/* Check for existing pm domains */
for (i = 0; i < ZYNQMP_NUM_DOMAINS; i++) {
if (pd[i].node_id == idx)
goto done;
}
/**
* Add index in empty node_id of power domain list as no existing
* power domain found for current index.
*/
for (i = 0; i < ZYNQMP_NUM_DOMAINS; i++) {
if (pd[i].node_id == 0) {
pd[i].node_id = idx;
break;
}
}
done:
if (!genpd_data->domains[i] || i == ZYNQMP_NUM_DOMAINS)
return ERR_PTR(-ENOENT);
return genpd_data->domains[i];
}
static int zynqmp_gpd_probe(struct platform_device *pdev)
{
int i;
struct genpd_onecell_data *zynqmp_pd_data;
struct generic_pm_domain **domains;
struct zynqmp_pm_domain *pd;
struct device *dev = &pdev->dev;
eemi_ops = zynqmp_pm_get_eemi_ops();
if (IS_ERR(eemi_ops))
return PTR_ERR(eemi_ops);
pd = devm_kcalloc(dev, ZYNQMP_NUM_DOMAINS, sizeof(*pd), GFP_KERNEL);
if (!pd)
return -ENOMEM;
zynqmp_pd_data = devm_kzalloc(dev, sizeof(*zynqmp_pd_data), GFP_KERNEL);
if (!zynqmp_pd_data)
return -ENOMEM;
zynqmp_pd_data->xlate = zynqmp_gpd_xlate;
domains = devm_kcalloc(dev, ZYNQMP_NUM_DOMAINS, sizeof(*domains),
GFP_KERNEL);
if (!domains)
return -ENOMEM;
for (i = 0; i < ZYNQMP_NUM_DOMAINS; i++, pd++) {
pd->node_id = 0;
pd->gpd.name = kasprintf(GFP_KERNEL, "domain%d", i);
pd->gpd.power_off = zynqmp_gpd_power_off;
pd->gpd.power_on = zynqmp_gpd_power_on;
pd->gpd.attach_dev = zynqmp_gpd_attach_dev;
pd->gpd.detach_dev = zynqmp_gpd_detach_dev;
domains[i] = &pd->gpd;
/* Mark all PM domains as initially powered off */
pm_genpd_init(&pd->gpd, NULL, true);
}
zynqmp_pd_data->domains = domains;
zynqmp_pd_data->num_domains = ZYNQMP_NUM_DOMAINS;
of_genpd_add_provider_onecell(dev->parent->of_node, zynqmp_pd_data);
return 0;
}
static int zynqmp_gpd_remove(struct platform_device *pdev)
{
of_genpd_del_provider(pdev->dev.parent->of_node);
return 0;
}
static struct platform_driver zynqmp_power_domain_driver = {
.driver = {
.name = "zynqmp_power_controller",
},
.probe = zynqmp_gpd_probe,
.remove = zynqmp_gpd_remove,
};
module_platform_driver(zynqmp_power_domain_driver);
MODULE_ALIAS("platform:zynqmp_power_controller");
