drivers/soc/ti/pruss.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-only
 /*
  * PRU-ICSS platform driver for various TI SoCs
  *
  * Copyright (C) 2014-2020 Texas Instruments Incorporated - http://www.ti.com/
  * Author(s):
  *	Suman Anna <s-anna@ti.com>
  *	Andrew F. Davis <afd@ti.com>
  *	Tero Kristo <t-kristo@ti.com>
  */

 #include <linux/clk-provider.h>
 #include <linux/dma-mapping.h>
 #include <linux/io.h>
 #include <linux/mfd/syscon.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/of_address.h>
 #include <linux/of_platform.h>
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
 #include <linux/pruss_driver.h>
 #include <linux/regmap.h>
 #include <linux/remoteproc.h>
 #include <linux/slab.h>
 #include "pruss.h"

 /**
  * struct pruss_private_data - PRUSS driver private data
  * @has_no_sharedram: flag to indicate the absence of PRUSS Shared Data RAM
  * @has_core_mux_clock: flag to indicate the presence of PRUSS core clock
  */
 struct pruss_private_data {
 	bool has_no_sharedram;
 	bool has_core_mux_clock;
 };

 /**
  * pruss_get() - get the pruss for a given PRU remoteproc
  * @rproc: remoteproc handle of a PRU instance
  *
  * Finds the parent pruss device for a PRU given the @rproc handle of the
  * PRU remote processor. This function increments the pruss device's refcount,
  * so always use pruss_put() to decrement it back once pruss isn't needed
  * anymore.
  *
  * This API doesn't check if @rproc is valid or not. It is expected the caller
  * will have done a pru_rproc_get() on @rproc, before calling this API to make
  * sure that @rproc is valid.
  *
  * Return: pruss handle on success, and an ERR_PTR on failure using one
  * of the following error values
  *    -EINVAL if invalid parameter
  *    -ENODEV if PRU device or PRUSS device is not found
  */
 struct pruss *pruss_get(struct rproc *rproc)
 {
 	struct pruss *pruss;
 	struct device *dev;
 	struct platform_device *ppdev;

 	if (IS_ERR_OR_NULL(rproc))
 		return ERR_PTR(-EINVAL);

 	dev = &rproc->dev;

 	/* make sure it is PRU rproc */
 	if (!dev->parent || !is_pru_rproc(dev->parent))
 		return ERR_PTR(-ENODEV);

 	ppdev = to_platform_device(dev->parent->parent);
 	pruss = platform_get_drvdata(ppdev);
 	if (!pruss)
 		return ERR_PTR(-ENODEV);

 	get_device(pruss->dev);

 	return pruss;
 }
 EXPORT_SYMBOL_GPL(pruss_get);

 /**
  * pruss_put() - decrement pruss device's usecount
  * @pruss: pruss handle
  *
  * Complimentary function for pruss_get(). Needs to be called
  * after the PRUSS is used, and only if the pruss_get() succeeds.
  */
 void pruss_put(struct pruss *pruss)
 {
 	if (IS_ERR_OR_NULL(pruss))
 		return;

 	put_device(pruss->dev);
 }
 EXPORT_SYMBOL_GPL(pruss_put);

 /**
  * pruss_request_mem_region() - request a memory resource
  * @pruss: the pruss instance
  * @mem_id: the memory resource id
  * @region: pointer to memory region structure to be filled in
  *
  * This function allows a client driver to request a memory resource,
  * and if successful, will let the client driver own the particular
  * memory region until released using the pruss_release_mem_region()
  * API.
  *
  * Return: 0 if requested memory region is available (in such case pointer to
  * memory region is returned via @region), an error otherwise
  */
 int pruss_request_mem_region(struct pruss *pruss, enum pruss_mem mem_id,
 			     struct pruss_mem_region *region)
 {
 	if (!pruss || !region || mem_id >= PRUSS_MEM_MAX)
 		return -EINVAL;

 	mutex_lock(&pruss->lock);

 	if (pruss->mem_in_use[mem_id]) {
 		mutex_unlock(&pruss->lock);
 		return -EBUSY;
 	}

 	*region = pruss->mem_regions[mem_id];
 	pruss->mem_in_use[mem_id] = region;

 	mutex_unlock(&pruss->lock);

 	return 0;
 }
 EXPORT_SYMBOL_GPL(pruss_request_mem_region);

 /**
  * pruss_release_mem_region() - release a memory resource
  * @pruss: the pruss instance
  * @region: the memory region to release
  *
  * This function is the complimentary function to
  * pruss_request_mem_region(), and allows the client drivers to
  * release back a memory resource.
  *
  * Return: 0 on success, an error code otherwise
  */
 int pruss_release_mem_region(struct pruss *pruss,
 			     struct pruss_mem_region *region)
 {
 	int id;

 	if (!pruss || !region)
 		return -EINVAL;

 	mutex_lock(&pruss->lock);

 	/* find out the memory region being released */
 	for (id = 0; id < PRUSS_MEM_MAX; id++) {
 		if (pruss->mem_in_use[id] == region)
 			break;
 	}

 	if (id == PRUSS_MEM_MAX) {
 		mutex_unlock(&pruss->lock);
 		return -EINVAL;
 	}

 	pruss->mem_in_use[id] = NULL;

 	mutex_unlock(&pruss->lock);

 	return 0;
 }
 EXPORT_SYMBOL_GPL(pruss_release_mem_region);

 /**
  * pruss_cfg_get_gpmux() - get the current GPMUX value for a PRU device
  * @pruss: pruss instance
  * @pru_id: PRU identifier (0-1)
  * @mux: pointer to store the current mux value into
  *
  * Return: 0 on success, or an error code otherwise
  */
 int pruss_cfg_get_gpmux(struct pruss *pruss, enum pruss_pru_id pru_id, u8 *mux)
 {
 	int ret;
 	u32 val;

 	if (pru_id >= PRUSS_NUM_PRUS || !mux)
 		return -EINVAL;

 	ret = pruss_cfg_read(pruss, PRUSS_CFG_GPCFG(pru_id), &val);
 	if (!ret)
 		*mux = (u8)((val & PRUSS_GPCFG_PRU_MUX_SEL_MASK) >>
 			    PRUSS_GPCFG_PRU_MUX_SEL_SHIFT);
 	return ret;
 }
 EXPORT_SYMBOL_GPL(pruss_cfg_get_gpmux);

 /**
  * pruss_cfg_set_gpmux() - set the GPMUX value for a PRU device
  * @pruss: pruss instance
  * @pru_id: PRU identifier (0-1)
  * @mux: new mux value for PRU
  *
  * Return: 0 on success, or an error code otherwise
  */
 int pruss_cfg_set_gpmux(struct pruss *pruss, enum pruss_pru_id pru_id, u8 mux)
 {
 	if (mux >= PRUSS_GP_MUX_SEL_MAX ||
 	    pru_id >= PRUSS_NUM_PRUS)
 		return -EINVAL;

 	return pruss_cfg_update(pruss, PRUSS_CFG_GPCFG(pru_id),
 				PRUSS_GPCFG_PRU_MUX_SEL_MASK,
 				(u32)mux << PRUSS_GPCFG_PRU_MUX_SEL_SHIFT);
 }
 EXPORT_SYMBOL_GPL(pruss_cfg_set_gpmux);

 /**
  * pruss_cfg_gpimode() - set the GPI mode of the PRU
  * @pruss: the pruss instance handle
  * @pru_id: id of the PRU core within the PRUSS
  * @mode: GPI mode to set
  *
  * Sets the GPI mode for a given PRU by programming the
  * corresponding PRUSS_CFG_GPCFGx register
  *
  * Return: 0 on success, or an error code otherwise
  */
 int pruss_cfg_gpimode(struct pruss *pruss, enum pruss_pru_id pru_id,
 		      enum pruss_gpi_mode mode)
 {
 	if (pru_id >= PRUSS_NUM_PRUS || mode >= PRUSS_GPI_MODE_MAX)
 		return -EINVAL;

 	return pruss_cfg_update(pruss, PRUSS_CFG_GPCFG(pru_id),
 				PRUSS_GPCFG_PRU_GPI_MODE_MASK,
 				mode << PRUSS_GPCFG_PRU_GPI_MODE_SHIFT);
 }
 EXPORT_SYMBOL_GPL(pruss_cfg_gpimode);

 /**
  * pruss_cfg_miirt_enable() - Enable/disable MII RT Events
  * @pruss: the pruss instance
  * @enable: enable/disable
  *
  * Enable/disable the MII RT Events for the PRUSS.
  *
  * Return: 0 on success, or an error code otherwise
  */
 int pruss_cfg_miirt_enable(struct pruss *pruss, bool enable)
 {
 	u32 set = enable ? PRUSS_MII_RT_EVENT_EN : 0;

 	return pruss_cfg_update(pruss, PRUSS_CFG_MII_RT,
 				PRUSS_MII_RT_EVENT_EN, set);
 }
 EXPORT_SYMBOL_GPL(pruss_cfg_miirt_enable);

 /**
  * pruss_cfg_xfr_enable() - Enable/disable XIN XOUT shift functionality
  * @pruss: the pruss instance
  * @pru_type: PRU core type identifier
  * @enable: enable/disable
  *
  * Return: 0 on success, or an error code otherwise
  */
 int pruss_cfg_xfr_enable(struct pruss *pruss, enum pru_type pru_type,
 			 bool enable)
 {
 	u32 mask, set;

 	switch (pru_type) {
 	case PRU_TYPE_PRU:
 		mask = PRUSS_SPP_XFER_SHIFT_EN;
 		break;
 	case PRU_TYPE_RTU:
 		mask = PRUSS_SPP_RTU_XFR_SHIFT_EN;
 		break;
 	default:
 		return -EINVAL;
 	}

 	set = enable ? mask : 0;

 	return pruss_cfg_update(pruss, PRUSS_CFG_SPP, mask, set);
 }
 EXPORT_SYMBOL_GPL(pruss_cfg_xfr_enable);

 static void pruss_of_free_clk_provider(void *data)
 {
 	struct device_node *clk_mux_np = data;

 	of_clk_del_provider(clk_mux_np);
 	of_node_put(clk_mux_np);
 }

 static void pruss_clk_unregister_mux(void *data)
 {
 	clk_unregister_mux(data);
 }

 static int pruss_clk_mux_setup(struct pruss *pruss, struct clk *clk_mux,
 			       char *mux_name, struct device_node *clks_np)
 {
 	struct device_node *clk_mux_np;
 	struct device *dev = pruss->dev;
 	char *clk_mux_name;
 	unsigned int num_parents;
 	const char **parent_names;
 	void __iomem *reg;
 	u32 reg_offset;
 	int ret;

 	clk_mux_np = of_get_child_by_name(clks_np, mux_name);
 	if (!clk_mux_np) {
 		dev_err(dev, "%pOF is missing its '%s' node\n", clks_np,
 			mux_name);
 		return -ENODEV;
 	}

 	num_parents = of_clk_get_parent_count(clk_mux_np);
 	if (num_parents < 1) {
 		dev_err(dev, "mux-clock %pOF must have parents\n", clk_mux_np);
 		ret = -EINVAL;
 		goto put_clk_mux_np;
 	}

 	parent_names = devm_kcalloc(dev, sizeof(*parent_names), num_parents,
 				    GFP_KERNEL);
 	if (!parent_names) {
 		ret = -ENOMEM;
 		goto put_clk_mux_np;
 	}

 	of_clk_parent_fill(clk_mux_np, parent_names, num_parents);

 	clk_mux_name = devm_kasprintf(dev, GFP_KERNEL, "%s.%pOFn",
 				      dev_name(dev), clk_mux_np);
 	if (!clk_mux_name) {
 		ret = -ENOMEM;
 		goto put_clk_mux_np;
 	}

 	ret = of_property_read_u32(clk_mux_np, "reg", &reg_offset);
 	if (ret)
 		goto put_clk_mux_np;

 	reg = pruss->cfg_base + reg_offset;

 	clk_mux = clk_register_mux(NULL, clk_mux_name, parent_names,
 				   num_parents, 0, reg, 0, 1, 0, NULL);
 	if (IS_ERR(clk_mux)) {
 		ret = PTR_ERR(clk_mux);
 		goto put_clk_mux_np;
 	}

 	ret = devm_add_action_or_reset(dev, pruss_clk_unregister_mux, clk_mux);
 	if (ret) {
 		dev_err(dev, "failed to add clkmux unregister action %d", ret);
 		goto put_clk_mux_np;
 	}

 	ret = of_clk_add_provider(clk_mux_np, of_clk_src_simple_get, clk_mux);
 	if (ret)
 		goto put_clk_mux_np;

 	ret = devm_add_action_or_reset(dev, pruss_of_free_clk_provider,
 				       clk_mux_np);
 	if (ret) {
 		dev_err(dev, "failed to add clkmux free action %d", ret);
 		goto put_clk_mux_np;
 	}

 	return 0;

 put_clk_mux_np:
 	of_node_put(clk_mux_np);
 	return ret;
 }

 static int pruss_clk_init(struct pruss *pruss, struct device_node *cfg_node)
 {
 	const struct pruss_private_data *data;
 	struct device_node *clks_np;
 	struct device *dev = pruss->dev;
 	int ret = 0;

 	data = of_device_get_match_data(dev);

 	clks_np = of_get_child_by_name(cfg_node, "clocks");
 	if (!clks_np) {
 		dev_err(dev, "%pOF is missing its 'clocks' node\n", cfg_node);
 		return -ENODEV;
 	}

 	if (data && data->has_core_mux_clock) {
 		ret = pruss_clk_mux_setup(pruss, pruss->core_clk_mux,
 					  "coreclk-mux", clks_np);
 		if (ret) {
 			dev_err(dev, "failed to setup coreclk-mux\n");
 			goto put_clks_node;
 		}
 	}

 	ret = pruss_clk_mux_setup(pruss, pruss->iep_clk_mux, "iepclk-mux",
 				  clks_np);
 	if (ret) {
 		dev_err(dev, "failed to setup iepclk-mux\n");
 		goto put_clks_node;
 	}

 put_clks_node:
 	of_node_put(clks_np);

 	return ret;
 }

 static struct regmap_config regmap_conf = {
 	.reg_bits = 32,
 	.val_bits = 32,
 	.reg_stride = 4,
 };

 static int pruss_cfg_of_init(struct device *dev, struct pruss *pruss)
 {
 	struct device_node *np = dev_of_node(dev);
 	struct device_node *child;
 	struct resource res;
 	int ret;

 	child = of_get_child_by_name(np, "cfg");
 	if (!child) {
 		dev_err(dev, "%pOF is missing its 'cfg' node\n", child);
 		return -ENODEV;
 	}

 	if (of_address_to_resource(child, 0, &res)) {
 		ret = -ENOMEM;
 		goto node_put;
 	}

 	pruss->cfg_base = devm_ioremap(dev, res.start, resource_size(&res));
 	if (!pruss->cfg_base) {
 		ret = -ENOMEM;
 		goto node_put;
 	}

 	regmap_conf.name = kasprintf(GFP_KERNEL, "%pOFn@%llx", child,
 				     (u64)res.start);
 	regmap_conf.max_register = resource_size(&res) - 4;

 	pruss->cfg_regmap = devm_regmap_init_mmio(dev, pruss->cfg_base,
 						  &regmap_conf);
 	kfree(regmap_conf.name);
 	if (IS_ERR(pruss->cfg_regmap)) {
 		dev_err(dev, "regmap_init_mmio failed for cfg, ret = %ld\n",
 			PTR_ERR(pruss->cfg_regmap));
 		ret = PTR_ERR(pruss->cfg_regmap);
 		goto node_put;
 	}

 	ret = pruss_clk_init(pruss, child);
 	if (ret)
 		dev_err(dev, "pruss_clk_init failed, ret = %d\n", ret);

 node_put:
 	of_node_put(child);
 	return ret;
 }

 static int pruss_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
 	struct device_node *np = dev_of_node(dev);
 	struct device_node *child;
 	struct pruss *pruss;
 	struct resource res;
 	int ret, i, index;
 	const struct pruss_private_data *data;
 	const char *mem_names[PRUSS_MEM_MAX] = { "dram0", "dram1", "shrdram2" };

 	data = of_device_get_match_data(&pdev->dev);

 	ret = dma_set_coherent_mask(dev, DMA_BIT_MASK(32));
 	if (ret) {
 		dev_err(dev, "failed to set the DMA coherent mask");
 		return ret;
 	}

 	pruss = devm_kzalloc(dev, sizeof(*pruss), GFP_KERNEL);
 	if (!pruss)
 		return -ENOMEM;

 	pruss->dev = dev;
 	mutex_init(&pruss->lock);

 	child = of_get_child_by_name(np, "memories");
 	if (!child) {
 		dev_err(dev, "%pOF is missing its 'memories' node\n", child);
 		return -ENODEV;
 	}

 	for (i = 0; i < PRUSS_MEM_MAX; i++) {
 		/*
 		 * On AM437x one of two PRUSS units don't contain Shared RAM,
 		 * skip it
 		 */
 		if (data && data->has_no_sharedram && i == PRUSS_MEM_SHRD_RAM2)
 			continue;

 		index = of_property_match_string(child, "reg-names",
 						 mem_names[i]);
 		if (index < 0) {
 			of_node_put(child);
 			return index;
 		}

 		if (of_address_to_resource(child, index, &res)) {
 			of_node_put(child);
 			return -EINVAL;
 		}

 		pruss->mem_regions[i].va = devm_ioremap(dev, res.start,
 							resource_size(&res));
 		if (!pruss->mem_regions[i].va) {
 			dev_err(dev, "failed to parse and map memory resource %d %s\n",
 				i, mem_names[i]);
 			of_node_put(child);
 			return -ENOMEM;
 		}
 		pruss->mem_regions[i].pa = res.start;
 		pruss->mem_regions[i].size = resource_size(&res);

 		dev_dbg(dev, "memory %8s: pa %pa size 0x%zx va %pK\n",
 			mem_names[i], &pruss->mem_regions[i].pa,
 			pruss->mem_regions[i].size, pruss->mem_regions[i].va);
 	}
 	of_node_put(child);

 	platform_set_drvdata(pdev, pruss);

 	pm_runtime_enable(dev);
 	ret = pm_runtime_resume_and_get(dev);
 	if (ret < 0) {
 		dev_err(dev, "couldn't enable module\n");
 		goto rpm_disable;
 	}

 	ret = pruss_cfg_of_init(dev, pruss);
 	if (ret < 0)
 		goto rpm_put;

 	ret = devm_of_platform_populate(dev);
 	if (ret) {
 		dev_err(dev, "failed to register child devices\n");
 		goto rpm_put;
 	}

 	return 0;

 rpm_put:
 	pm_runtime_put_sync(dev);
 rpm_disable:
 	pm_runtime_disable(dev);
 	return ret;
 }

 static void pruss_remove(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;

 	devm_of_platform_depopulate(dev);

 	pm_runtime_put_sync(dev);
 	pm_runtime_disable(dev);
 }

 /* instance-specific driver private data */
 static const struct pruss_private_data am437x_pruss1_data = {
 	.has_no_sharedram = false,
 };

 static const struct pruss_private_data am437x_pruss0_data = {
 	.has_no_sharedram = true,
 };

 static const struct pruss_private_data am65x_j721e_pruss_data = {
 	.has_core_mux_clock = true,
 };

 static const struct of_device_id pruss_of_match[] = {
 	{ .compatible = "ti,am3356-pruss" },
 	{ .compatible = "ti,am4376-pruss0", .data = &am437x_pruss0_data, },
 	{ .compatible = "ti,am4376-pruss1", .data = &am437x_pruss1_data, },
 	{ .compatible = "ti,am5728-pruss" },
 	{ .compatible = "ti,k2g-pruss" },
 	{ .compatible = "ti,am654-icssg", .data = &am65x_j721e_pruss_data, },
 	{ .compatible = "ti,j721e-icssg", .data = &am65x_j721e_pruss_data, },
 	{ .compatible = "ti,am642-icssg", .data = &am65x_j721e_pruss_data, },
 	{ .compatible = "ti,am625-pruss", .data = &am65x_j721e_pruss_data, },
 	{},
 };
 MODULE_DEVICE_TABLE(of, pruss_of_match);

 static struct platform_driver pruss_driver = {
 	.driver = {
 		.name = "pruss",
 		.of_match_table = pruss_of_match,
 	},
 	.probe  = pruss_probe,
 	.remove_new = pruss_remove,
 };
 module_platform_driver(pruss_driver);

 MODULE_AUTHOR("Suman Anna <s-anna@ti.com>");
 MODULE_DESCRIPTION("PRU-ICSS Subsystem Driver");
 MODULE_LICENSE("GPL v2");
	// SPDX-License-Identifier: GPL-2.0-only
	/*
	* PRU-ICSS platform driver for various TI SoCs
	*
	* Copyright (C) 2014-2020 Texas Instruments Incorporated - http://www.ti.com/
	* Author(s):
	* Suman Anna <s-anna@ti.com>
	* Andrew F. Davis <afd@ti.com>
	* Tero Kristo <t-kristo@ti.com>
	*/

	#include <linux/clk-provider.h>
	#include <linux/dma-mapping.h>
	#include <linux/io.h>
	#include <linux/mfd/syscon.h>
	#include <linux/module.h>
	#include <linux/of.h>
	#include <linux/of_address.h>
	#include <linux/of_platform.h>
	#include <linux/platform_device.h>
	#include <linux/pm_runtime.h>
	#include <linux/pruss_driver.h>
	#include <linux/regmap.h>
	#include <linux/remoteproc.h>
	#include <linux/slab.h>
	#include "pruss.h"

	/**
	* struct pruss_private_data - PRUSS driver private data
	* @has_no_sharedram: flag to indicate the absence of PRUSS Shared Data RAM
	* @has_core_mux_clock: flag to indicate the presence of PRUSS core clock
	*/
	struct pruss_private_data {
	bool has_no_sharedram;
	bool has_core_mux_clock;
	};

	/**
	* pruss_get() - get the pruss for a given PRU remoteproc
	* @rproc: remoteproc handle of a PRU instance
	*
	* Finds the parent pruss device for a PRU given the @rproc handle of the
	* PRU remote processor. This function increments the pruss device's refcount,
	* so always use pruss_put() to decrement it back once pruss isn't needed
	* anymore.
	*
	* This API doesn't check if @rproc is valid or not. It is expected the caller
	* will have done a pru_rproc_get() on @rproc, before calling this API to make
	* sure that @rproc is valid.
	*
	* Return: pruss handle on success, and an ERR_PTR on failure using one
	* of the following error values
	* -EINVAL if invalid parameter
	* -ENODEV if PRU device or PRUSS device is not found
	*/
	struct pruss pruss_get(struct rproc rproc)
	{
	struct pruss *pruss;
	struct device *dev;
	struct platform_device *ppdev;

	if (IS_ERR_OR_NULL(rproc))
	return ERR_PTR(-EINVAL);

	dev = &rproc->dev;

	/* make sure it is PRU rproc */
	if (!dev->parent \|\| !is_pru_rproc(dev->parent))
	return ERR_PTR(-ENODEV);

	ppdev = to_platform_device(dev->parent->parent);
	pruss = platform_get_drvdata(ppdev);
	if (!pruss)
	return ERR_PTR(-ENODEV);

	get_device(pruss->dev);

	return pruss;
	}
	EXPORT_SYMBOL_GPL(pruss_get);

	/**
	* pruss_put() - decrement pruss device's usecount
	* @pruss: pruss handle
	*
	* Complimentary function for pruss_get(). Needs to be called
	* after the PRUSS is used, and only if the pruss_get() succeeds.
	*/
	void pruss_put(struct pruss *pruss)
	{
	if (IS_ERR_OR_NULL(pruss))
	return;

	put_device(pruss->dev);
	}
	EXPORT_SYMBOL_GPL(pruss_put);

	/**
	* pruss_request_mem_region() - request a memory resource
	* @pruss: the pruss instance
	* @mem_id: the memory resource id
	* @region: pointer to memory region structure to be filled in
	*
	* This function allows a client driver to request a memory resource,
	* and if successful, will let the client driver own the particular
	* memory region until released using the pruss_release_mem_region()
	* API.
	*
	* Return: 0 if requested memory region is available (in such case pointer to
	* memory region is returned via @region), an error otherwise
	*/
	int pruss_request_mem_region(struct pruss *pruss, enum pruss_mem mem_id,
	struct pruss_mem_region *region)
	{
	if (!pruss \|\| !region \|\| mem_id >= PRUSS_MEM_MAX)
	return -EINVAL;

	mutex_lock(&pruss->lock);

	if (pruss->mem_in_use[mem_id]) {
	mutex_unlock(&pruss->lock);
	return -EBUSY;
	}

	*region = pruss->mem_regions[mem_id];
	pruss->mem_in_use[mem_id] = region;

	mutex_unlock(&pruss->lock);

	return 0;
	}
	EXPORT_SYMBOL_GPL(pruss_request_mem_region);

	/**
	* pruss_release_mem_region() - release a memory resource
	* @pruss: the pruss instance
	* @region: the memory region to release
	*
	* This function is the complimentary function to
	* pruss_request_mem_region(), and allows the client drivers to
	* release back a memory resource.
	*
	* Return: 0 on success, an error code otherwise
	*/
	int pruss_release_mem_region(struct pruss *pruss,
	struct pruss_mem_region *region)
	{
	int id;

	if (!pruss \|\| !region)
	return -EINVAL;

	mutex_lock(&pruss->lock);

	/* find out the memory region being released */
	for (id = 0; id < PRUSS_MEM_MAX; id++) {
	if (pruss->mem_in_use[id] == region)
	break;
	}

	if (id == PRUSS_MEM_MAX) {
	mutex_unlock(&pruss->lock);
	return -EINVAL;
	}

	pruss->mem_in_use[id] = NULL;

	mutex_unlock(&pruss->lock);

	return 0;
	}
	EXPORT_SYMBOL_GPL(pruss_release_mem_region);

	/**
	* pruss_cfg_get_gpmux() - get the current GPMUX value for a PRU device
	* @pruss: pruss instance
	* @pru_id: PRU identifier (0-1)
	* @mux: pointer to store the current mux value into
	*
	* Return: 0 on success, or an error code otherwise
	*/
	int pruss_cfg_get_gpmux(struct pruss pruss, enum pruss_pru_id pru_id, u8 mux)
	{
	int ret;
	u32 val;

	if (pru_id >= PRUSS_NUM_PRUS \|\| !mux)
	return -EINVAL;

	ret = pruss_cfg_read(pruss, PRUSS_CFG_GPCFG(pru_id), &val);
	if (!ret)
	*mux = (u8)((val & PRUSS_GPCFG_PRU_MUX_SEL_MASK) >>
	PRUSS_GPCFG_PRU_MUX_SEL_SHIFT);
	return ret;
	}
	EXPORT_SYMBOL_GPL(pruss_cfg_get_gpmux);

	/**
	* pruss_cfg_set_gpmux() - set the GPMUX value for a PRU device
	* @pruss: pruss instance
	* @pru_id: PRU identifier (0-1)
	* @mux: new mux value for PRU
	*
	* Return: 0 on success, or an error code otherwise
	*/
	int pruss_cfg_set_gpmux(struct pruss *pruss, enum pruss_pru_id pru_id, u8 mux)
	{
	if (mux >= PRUSS_GP_MUX_SEL_MAX \|\|
	pru_id >= PRUSS_NUM_PRUS)
	return -EINVAL;

	return pruss_cfg_update(pruss, PRUSS_CFG_GPCFG(pru_id),
	PRUSS_GPCFG_PRU_MUX_SEL_MASK,
	(u32)mux << PRUSS_GPCFG_PRU_MUX_SEL_SHIFT);
	}
	EXPORT_SYMBOL_GPL(pruss_cfg_set_gpmux);

	/**
	* pruss_cfg_gpimode() - set the GPI mode of the PRU
	* @pruss: the pruss instance handle
	* @pru_id: id of the PRU core within the PRUSS
	* @mode: GPI mode to set
	*
	* Sets the GPI mode for a given PRU by programming the
	* corresponding PRUSS_CFG_GPCFGx register
	*
	* Return: 0 on success, or an error code otherwise
	*/
	int pruss_cfg_gpimode(struct pruss *pruss, enum pruss_pru_id pru_id,
	enum pruss_gpi_mode mode)
	{
	if (pru_id >= PRUSS_NUM_PRUS \|\| mode >= PRUSS_GPI_MODE_MAX)
	return -EINVAL;

	return pruss_cfg_update(pruss, PRUSS_CFG_GPCFG(pru_id),
	PRUSS_GPCFG_PRU_GPI_MODE_MASK,
	mode << PRUSS_GPCFG_PRU_GPI_MODE_SHIFT);
	}
	EXPORT_SYMBOL_GPL(pruss_cfg_gpimode);

	/**
	* pruss_cfg_miirt_enable() - Enable/disable MII RT Events
	* @pruss: the pruss instance
	* @enable: enable/disable
	*
	* Enable/disable the MII RT Events for the PRUSS.
	*
	* Return: 0 on success, or an error code otherwise
	*/
	int pruss_cfg_miirt_enable(struct pruss *pruss, bool enable)
	{
	u32 set = enable ? PRUSS_MII_RT_EVENT_EN : 0;

	return pruss_cfg_update(pruss, PRUSS_CFG_MII_RT,
	PRUSS_MII_RT_EVENT_EN, set);
	}
	EXPORT_SYMBOL_GPL(pruss_cfg_miirt_enable);

	/**
	* pruss_cfg_xfr_enable() - Enable/disable XIN XOUT shift functionality
	* @pruss: the pruss instance
	* @pru_type: PRU core type identifier
	* @enable: enable/disable
	*
	* Return: 0 on success, or an error code otherwise
	*/
	int pruss_cfg_xfr_enable(struct pruss *pruss, enum pru_type pru_type,
	bool enable)
	{
	u32 mask, set;

	switch (pru_type) {
	case PRU_TYPE_PRU:
	mask = PRUSS_SPP_XFER_SHIFT_EN;
	break;
	case PRU_TYPE_RTU:
	mask = PRUSS_SPP_RTU_XFR_SHIFT_EN;
	break;
	default:
	return -EINVAL;
	}

	set = enable ? mask : 0;

	return pruss_cfg_update(pruss, PRUSS_CFG_SPP, mask, set);
	}
	EXPORT_SYMBOL_GPL(pruss_cfg_xfr_enable);

	static void pruss_of_free_clk_provider(void *data)
	{
	struct device_node *clk_mux_np = data;

	of_clk_del_provider(clk_mux_np);
	of_node_put(clk_mux_np);
	}

	static void pruss_clk_unregister_mux(void *data)
	{
	clk_unregister_mux(data);
	}

	static int pruss_clk_mux_setup(struct pruss pruss, struct clk clk_mux,
	char mux_name, struct device_node clks_np)
	{
	struct device_node *clk_mux_np;
	struct device *dev = pruss->dev;
	char *clk_mux_name;
	unsigned int num_parents;
	const char **parent_names;
	void __iomem *reg;
	u32 reg_offset;
	int ret;

	clk_mux_np = of_get_child_by_name(clks_np, mux_name);
	if (!clk_mux_np) {
	dev_err(dev, "%pOF is missing its '%s' node\n", clks_np,
	mux_name);
	return -ENODEV;
	}

	num_parents = of_clk_get_parent_count(clk_mux_np);
	if (num_parents < 1) {
	dev_err(dev, "mux-clock %pOF must have parents\n", clk_mux_np);
	ret = -EINVAL;
	goto put_clk_mux_np;
	}

	parent_names = devm_kcalloc(dev, sizeof(*parent_names), num_parents,
	GFP_KERNEL);
	if (!parent_names) {
	ret = -ENOMEM;
	goto put_clk_mux_np;
	}

	of_clk_parent_fill(clk_mux_np, parent_names, num_parents);

	clk_mux_name = devm_kasprintf(dev, GFP_KERNEL, "%s.%pOFn",
	dev_name(dev), clk_mux_np);
	if (!clk_mux_name) {
	ret = -ENOMEM;
	goto put_clk_mux_np;
	}

	ret = of_property_read_u32(clk_mux_np, "reg", &reg_offset);
	if (ret)
	goto put_clk_mux_np;

	reg = pruss->cfg_base + reg_offset;

	clk_mux = clk_register_mux(NULL, clk_mux_name, parent_names,
	num_parents, 0, reg, 0, 1, 0, NULL);
	if (IS_ERR(clk_mux)) {
	ret = PTR_ERR(clk_mux);
	goto put_clk_mux_np;
	}

	ret = devm_add_action_or_reset(dev, pruss_clk_unregister_mux, clk_mux);
	if (ret) {
	dev_err(dev, "failed to add clkmux unregister action %d", ret);
	goto put_clk_mux_np;
	}

	ret = of_clk_add_provider(clk_mux_np, of_clk_src_simple_get, clk_mux);
	if (ret)
	goto put_clk_mux_np;

	ret = devm_add_action_or_reset(dev, pruss_of_free_clk_provider,
	clk_mux_np);
	if (ret) {
	dev_err(dev, "failed to add clkmux free action %d", ret);
	goto put_clk_mux_np;
	}

	return 0;

	put_clk_mux_np:
	of_node_put(clk_mux_np);
	return ret;
	}

	static int pruss_clk_init(struct pruss pruss, struct device_node cfg_node)
	{
	const struct pruss_private_data *data;
	struct device_node *clks_np;
	struct device *dev = pruss->dev;
	int ret = 0;

	data = of_device_get_match_data(dev);

	clks_np = of_get_child_by_name(cfg_node, "clocks");
	if (!clks_np) {
	dev_err(dev, "%pOF is missing its 'clocks' node\n", cfg_node);
	return -ENODEV;
	}

	if (data && data->has_core_mux_clock) {
	ret = pruss_clk_mux_setup(pruss, pruss->core_clk_mux,
	"coreclk-mux", clks_np);
	if (ret) {
	dev_err(dev, "failed to setup coreclk-mux\n");
	goto put_clks_node;
	}
	}

	ret = pruss_clk_mux_setup(pruss, pruss->iep_clk_mux, "iepclk-mux",
	clks_np);
	if (ret) {
	dev_err(dev, "failed to setup iepclk-mux\n");
	goto put_clks_node;
	}

	put_clks_node:
	of_node_put(clks_np);

	return ret;
	}

	static struct regmap_config regmap_conf = {
	.reg_bits = 32,
	.val_bits = 32,
	.reg_stride = 4,
	};

	static int pruss_cfg_of_init(struct device dev, struct pruss pruss)
	{
	struct device_node *np = dev_of_node(dev);
	struct device_node *child;
	struct resource res;
	int ret;

	child = of_get_child_by_name(np, "cfg");
	if (!child) {
	dev_err(dev, "%pOF is missing its 'cfg' node\n", child);
	return -ENODEV;
	}

	if (of_address_to_resource(child, 0, &res)) {
	ret = -ENOMEM;
	goto node_put;
	}

	pruss->cfg_base = devm_ioremap(dev, res.start, resource_size(&res));
	if (!pruss->cfg_base) {
	ret = -ENOMEM;
	goto node_put;
	}

	regmap_conf.name = kasprintf(GFP_KERNEL, "%pOFn@%llx", child,
	(u64)res.start);
	regmap_conf.max_register = resource_size(&res) - 4;

	pruss->cfg_regmap = devm_regmap_init_mmio(dev, pruss->cfg_base,
	&regmap_conf);
	kfree(regmap_conf.name);
	if (IS_ERR(pruss->cfg_regmap)) {
	dev_err(dev, "regmap_init_mmio failed for cfg, ret = %ld\n",
	PTR_ERR(pruss->cfg_regmap));
	ret = PTR_ERR(pruss->cfg_regmap);
	goto node_put;
	}

	ret = pruss_clk_init(pruss, child);
	if (ret)
	dev_err(dev, "pruss_clk_init failed, ret = %d\n", ret);

	node_put:
	of_node_put(child);
	return ret;
	}

	static int pruss_probe(struct platform_device *pdev)
	{
	struct device *dev = &pdev->dev;
	struct device_node *np = dev_of_node(dev);
	struct device_node *child;
	struct pruss *pruss;
	struct resource res;
	int ret, i, index;
	const struct pruss_private_data *data;
	const char *mem_names[PRUSS_MEM_MAX] = { "dram0", "dram1", "shrdram2" };

	data = of_device_get_match_data(&pdev->dev);

	ret = dma_set_coherent_mask(dev, DMA_BIT_MASK(32));
	if (ret) {
	dev_err(dev, "failed to set the DMA coherent mask");
	return ret;
	}

	pruss = devm_kzalloc(dev, sizeof(*pruss), GFP_KERNEL);
	if (!pruss)
	return -ENOMEM;

	pruss->dev = dev;
	mutex_init(&pruss->lock);

	child = of_get_child_by_name(np, "memories");
	if (!child) {
	dev_err(dev, "%pOF is missing its 'memories' node\n", child);
	return -ENODEV;
	}

	for (i = 0; i < PRUSS_MEM_MAX; i++) {
	/*
	* On AM437x one of two PRUSS units don't contain Shared RAM,
	* skip it
	*/
	if (data && data->has_no_sharedram && i == PRUSS_MEM_SHRD_RAM2)
	continue;

	index = of_property_match_string(child, "reg-names",
	mem_names[i]);
	if (index < 0) {
	of_node_put(child);
	return index;
	}

	if (of_address_to_resource(child, index, &res)) {
	of_node_put(child);
	return -EINVAL;
	}

	pruss->mem_regions[i].va = devm_ioremap(dev, res.start,
	resource_size(&res));
	if (!pruss->mem_regions[i].va) {
	dev_err(dev, "failed to parse and map memory resource %d %s\n",
	i, mem_names[i]);
	of_node_put(child);
	return -ENOMEM;
	}
	pruss->mem_regions[i].pa = res.start;
	pruss->mem_regions[i].size = resource_size(&res);

	dev_dbg(dev, "memory %8s: pa %pa size 0x%zx va %pK\n",
	mem_names[i], &pruss->mem_regions[i].pa,
	pruss->mem_regions[i].size, pruss->mem_regions[i].va);
	}
	of_node_put(child);

	platform_set_drvdata(pdev, pruss);

	pm_runtime_enable(dev);
	ret = pm_runtime_resume_and_get(dev);
	if (ret < 0) {
	dev_err(dev, "couldn't enable module\n");
	goto rpm_disable;
	}

	ret = pruss_cfg_of_init(dev, pruss);
	if (ret < 0)
	goto rpm_put;

	ret = devm_of_platform_populate(dev);
	if (ret) {
	dev_err(dev, "failed to register child devices\n");
	goto rpm_put;
	}

	return 0;

	rpm_put:
	pm_runtime_put_sync(dev);
	rpm_disable:
	pm_runtime_disable(dev);
	return ret;
	}

	static void pruss_remove(struct platform_device *pdev)
	{
	struct device *dev = &pdev->dev;

	devm_of_platform_depopulate(dev);

	pm_runtime_put_sync(dev);
	pm_runtime_disable(dev);
	}

	/* instance-specific driver private data */
	static const struct pruss_private_data am437x_pruss1_data = {
	.has_no_sharedram = false,
	};

	static const struct pruss_private_data am437x_pruss0_data = {
	.has_no_sharedram = true,
	};

	static const struct pruss_private_data am65x_j721e_pruss_data = {
	.has_core_mux_clock = true,
	};

	static const struct of_device_id pruss_of_match[] = {
	{ .compatible = "ti,am3356-pruss" },
	{ .compatible = "ti,am4376-pruss0", .data = &am437x_pruss0_data, },
	{ .compatible = "ti,am4376-pruss1", .data = &am437x_pruss1_data, },
	{ .compatible = "ti,am5728-pruss" },
	{ .compatible = "ti,k2g-pruss" },
	{ .compatible = "ti,am654-icssg", .data = &am65x_j721e_pruss_data, },
	{ .compatible = "ti,j721e-icssg", .data = &am65x_j721e_pruss_data, },
	{ .compatible = "ti,am642-icssg", .data = &am65x_j721e_pruss_data, },
	{ .compatible = "ti,am625-pruss", .data = &am65x_j721e_pruss_data, },
	{},
	};
	MODULE_DEVICE_TABLE(of, pruss_of_match);

	static struct platform_driver pruss_driver = {
	.driver = {
	.name = "pruss",
	.of_match_table = pruss_of_match,
	},
	.probe = pruss_probe,
	.remove_new = pruss_remove,
	};
	module_platform_driver(pruss_driver);

	MODULE_AUTHOR("Suman Anna <s-anna@ti.com>");
	MODULE_DESCRIPTION("PRU-ICSS Subsystem Driver");
	MODULE_LICENSE("GPL v2");