// SPDX-License-Identifier: GPL-2.0
/*
* ZynqMP Generic PM domain support
*
* Copyright (C) 2015-2019 Xilinx, Inc.
*
* Davorin Mista <[email protected]>
* Jolly Shah <[email protected]>
* Rajan Vaja <[email protected]>
*/
#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)
static int min_capability;
/**
* 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
* @requested: The PM node mapped to the PM domain has been requested
*/
struct zynqmp_pm_domain {
struct generic_pm_domain gpd;
u32 node_id;
bool requested;
};
#define to_zynqmp_pm_domain(pm_domain) \
container_of(pm_domain, struct zynqmp_pm_domain, gpd)
/**
* 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)
{
struct zynqmp_pm_domain *pd = to_zynqmp_pm_domain(domain);
int ret;
ret = zynqmp_pm_set_requirement(pd->node_id,
ZYNQMP_PM_CAPABILITY_ACCESS,
ZYNQMP_PM_MAX_QOS,
ZYNQMP_PM_REQUEST_ACK_BLOCKING);
if (ret) {
dev_err(&domain->dev,
"failed to set requirement to 0x%x for PM node id %d: %d\n",
ZYNQMP_PM_CAPABILITY_ACCESS, pd->node_id, ret);
return ret;
}
dev_dbg(&domain->dev, "set requirement to 0x%x for PM node id %d\n",
ZYNQMP_PM_CAPABILITY_ACCESS, pd->node_id);
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)
{
struct zynqmp_pm_domain *pd = to_zynqmp_pm_domain(domain);
int ret;
struct pm_domain_data *pdd, *tmp;
u32 capabilities = min_capability;
bool may_wakeup;
/* If domain is already released there is nothing to be done */
if (!pd->requested) {
dev_dbg(&domain->dev, "PM node id %d is already released\n",
pd->node_id);
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 = zynqmp_pm_set_requirement(pd->node_id, capabilities, 0,
ZYNQMP_PM_REQUEST_ACK_NO);
if (ret) {
dev_err(&domain->dev,
"failed to set requirement to 0x%x for PM node id %d: %d\n",
capabilities, pd->node_id, ret);
return ret;
}
dev_dbg(&domain->dev, "set requirement to 0x%x for PM node id %d\n",
capabilities, pd->node_id);
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)
{
struct zynqmp_pm_domain *pd = to_zynqmp_pm_domain(domain);
struct device_link *link;
int ret;
link = device_link_add(dev, &domain->dev, DL_FLAG_SYNC_STATE_ONLY);
if (!link)
dev_dbg(&domain->dev, "failed to create device link for %s\n",
dev_name(dev));
/* If this is not the first device to attach there is nothing to do */
if (domain->device_count)
return 0;
ret = zynqmp_pm_request_node(pd->node_id, 0, 0,
ZYNQMP_PM_REQUEST_ACK_BLOCKING);
if (ret) {
dev_err(&domain->dev, "%s request failed for node %d: %d\n",
domain->name, pd->node_id, ret);
return ret;
}
pd->requested = true;
dev_dbg(&domain->dev, "%s requested PM node id %d\n",
dev_name(dev), pd->node_id);
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)
{
struct zynqmp_pm_domain *pd = to_zynqmp_pm_domain(domain);
int ret;
/* If this is not the last device to detach there is nothing to do */
if (domain->device_count)
return;
ret = zynqmp_pm_release_node(pd->node_id);
if (ret) {
dev_err(&domain->dev, "failed to release PM node id %d: %d\n",
pd->node_id, ret);
return;
}
pd->requested = false;
dev_dbg(&domain->dev, "%s released PM node id %d\n",
dev_name(dev), pd->node_id);
}
static struct generic_pm_domain *zynqmp_gpd_xlate
(const 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 = to_zynqmp_pm_domain(genpd_data->domains[0]);
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;
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;
if (!of_device_is_compatible(dev->parent->of_node,
"xlnx,zynqmp-firmware"))
min_capability = ZYNQMP_PM_CAPABILITY_UNUSABLE;
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 void zynqmp_gpd_remove(struct platform_device *pdev)
{
of_genpd_del_provider(pdev->dev.parent->of_node);
}
static void zynqmp_gpd_sync_state(struct device *dev)
{
int ret;
ret = zynqmp_pm_init_finalize();
if (ret)
dev_warn(dev, "failed to release power management to firmware\n");
}
static struct platform_driver zynqmp_power_domain_driver = {
.driver = {
.name = "zynqmp_power_controller",
.sync_state = zynqmp_gpd_sync_state,
},
.probe = zynqmp_gpd_probe,
.remove_new = zynqmp_gpd_remove,
};
module_platform_driver(zynqmp_power_domain_driver);
MODULE_ALIAS("platform:zynqmp_power_controller");
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