diff options
Diffstat (limited to 'drivers/soc/xilinx/zynqmp_pm_domains.c')
-rw-r--r-- | drivers/soc/xilinx/zynqmp_pm_domains.c | 311 |
1 files changed, 311 insertions, 0 deletions
diff --git a/drivers/soc/xilinx/zynqmp_pm_domains.c b/drivers/soc/xilinx/zynqmp_pm_domains.c new file mode 100644 index 000000000..226d343f0 --- /dev/null +++ b/drivers/soc/xilinx/zynqmp_pm_domains.c @@ -0,0 +1,311 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * ZynqMP Generic PM domain support + * + * Copyright (C) 2015-2019 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 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 + * @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; + + pd = container_of(domain, struct zynqmp_pm_domain, gpd); + ret = zynqmp_pm_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 = min_capability; + bool may_wakeup; + + 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 = zynqmp_pm_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; + + 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 = zynqmp_pm_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; + + 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 = zynqmp_pm_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; + + 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 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"); |