drivers: soc: xilinx: Add ZynqMP power domain driver

The zynqmp-genpd driver communicates the usage requirements
for logical power domains / devices to the platform FW.
FW is responsible for choosing appropriate power states,
taking Linux' usage information into account.

Signed-off-by: Rajan Vaja <rajan.vaja@xilinx.com>
Signed-off-by: Jolly Shah <jolly.shah@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>

diff --git a/drivers/firmware/xilinx/Kconfig b/drivers/firmware/xilinx/Kconfig
index 8f44b9c..bd33bbf 100644 (file)
--- a/drivers/firmware/xilinx/Kconfig
+++ b/drivers/firmware/xilinx/Kconfig
@@ -6,6 +6,7 @@ menu "Zynq MPSoC Firmware Drivers"
 
 config ZYNQMP_FIRMWARE
        bool "Enable Xilinx Zynq MPSoC firmware interface"
+       select MFD_CORE
        help
          Firmware interface driver is used by different
          drivers to communicate with the firmware for

diff --git a/drivers/firmware/xilinx/zynqmp.c b/drivers/firmware/xilinx/zynqmp.c
index af5cffd..98f9361 100644 (file)
--- a/drivers/firmware/xilinx/zynqmp.c
+++ b/drivers/firmware/xilinx/zynqmp.c
@@ -14,6 +14,7 @@
 #include <linux/compiler.h>
 #include <linux/device.h>
 #include <linux/init.h>
+#include <linux/mfd/core.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/of_platform.h>
@@ -23,6 +24,12 @@
 #include <linux/firmware/xlnx-zynqmp.h>
 #include "zynqmp-debug.h"
 
+static const struct mfd_cell firmware_devs[] = {
+       {
+               .name = "zynqmp_power_controller",
+       },
+};
+
 /**
  * zynqmp_pm_ret_code() - Convert PMU-FW error codes to Linux error codes
  * @ret_status:                PMUFW return code
@@ -689,11 +696,19 @@ static int zynqmp_firmware_probe(struct platform_device *pdev)
 
        zynqmp_pm_api_debugfs_init();
 
+       ret = mfd_add_devices(&pdev->dev, PLATFORM_DEVID_NONE, firmware_devs,
+                             ARRAY_SIZE(firmware_devs), NULL, 0, NULL);
+       if (ret) {
+               dev_err(&pdev->dev, "failed to add MFD devices %d\n", ret);
+               return ret;
+       }
+
        return of_platform_populate(dev->of_node, NULL, NULL, dev);
 }
 
 static int zynqmp_firmware_remove(struct platform_device *pdev)
 {
+       mfd_remove_devices(&pdev->dev);
        zynqmp_pm_api_debugfs_exit();
 
        return 0;

diff --git a/drivers/soc/xilinx/Kconfig b/drivers/soc/xilinx/Kconfig
index 5025e0e..01e76b5 100644 (file)
--- a/drivers/soc/xilinx/Kconfig
+++ b/drivers/soc/xilinx/Kconfig
@@ -28,4 +28,13 @@ config ZYNQMP_POWER
          power management callbacks from firmware.
          If in doubt, say N.
 
+config ZYNQMP_PM_DOMAINS
+       bool "Enable Zynq MPSoC generic PM domains"
+       default y
+       depends on PM && ARCH_ZYNQMP && ZYNQMP_FIRMWARE
+       select PM_GENERIC_DOMAINS
+       help
+         Say yes to enable device power management through PM domains
+         If in doubt, say N.
+
 endmenu

diff --git a/drivers/soc/xilinx/Makefile b/drivers/soc/xilinx/Makefile
index 428b9db..f66bfea 100644 (file)
--- a/drivers/soc/xilinx/Makefile
+++ b/drivers/soc/xilinx/Makefile
@@ -1,3 +1,4 @@
 # SPDX-License-Identifier: GPL-2.0
 obj-$(CONFIG_XILINX_VCU)       += xlnx_vcu.o
 obj-$(CONFIG_ZYNQMP_POWER)     += zynqmp_power.o
+obj-$(CONFIG_ZYNQMP_PM_DOMAINS) += zynqmp_pm_domains.o

diff --git a/drivers/soc/xilinx/zynqmp_pm_domains.c b/drivers/soc/xilinx/zynqmp_pm_domains.c
new file mode 100644 (file)
index 0000000..354d256
--- /dev/null
+++ b/drivers/soc/xilinx/zynqmp_pm_domains.c
@@ -0,0 +1,321 @@
+// 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)
+
+/**
+ * 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;
+       const struct zynqmp_eemi_ops *eemi_ops = zynqmp_pm_get_eemi_ops();
+
+       if (!eemi_ops || !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;
+       const struct zynqmp_eemi_ops *eemi_ops = zynqmp_pm_get_eemi_ops();
+
+       if (!eemi_ops || !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;
+       const struct zynqmp_eemi_ops *eemi_ops = zynqmp_pm_get_eemi_ops();
+
+       if (!eemi_ops || !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;
+       const struct zynqmp_eemi_ops *eemi_ops = zynqmp_pm_get_eemi_ops();
+
+       if (!eemi_ops || !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;
+
+       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");