Commit e23d9c6d authored by Jolly Shah's avatar Jolly Shah Committed by Michal Simek
Browse files

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: default avatarRajan Vaja <rajan.vaja@xilinx.com>
Signed-off-by: default avatarJolly Shah <jolly.shah@xilinx.com>
Signed-off-by: default avatarMichal Simek <michal.simek@xilinx.com>
parent c1986ac3

drivers/firmware/xilinx/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -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

drivers/firmware/xilinx/zynqmp.c

+15 −0
Original line number Diff line number Diff line
@@ -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;

drivers/soc/xilinx/Kconfig

+9 −0
Original line number Diff line number Diff line
@@ -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

drivers/soc/xilinx/Makefile

+1 −0
Original line number Diff line number Diff line 
# 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

drivers/soc/xilinx/zynqmp_pm_domains.c

0 → 100644
+321 −0
Original line number Diff line number Diff line 
// 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");

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