// SPDX-License-Identifier: GPL-2.0#include <linux/kernel.h>#include <linux/of.h>#include <linux/of_device.h>#include <linux/of_address.h>#include <linux/of_iommu.h>#include <linux/of_reserved_mem.h>#include <linux/dma-direct.h> /* for bus_dma_region */#include <linux/dma-map-ops.h>#include <linux/init.h>#include <linux/slab.h>#include <linux/platform_device.h> #include <asm/errno.h>#include "of_private.h" /** * of_match_device - Tell if a struct device matches an of_device_id list * @matches: array of of_device_id match structures to search in * @dev: the OF device structure to match against * * Used by a driver to check whether an platform_device present in the * system is in its list of supported devices. */const struct of_device_id *of_match_device(const struct of_device_id *matches,					   const struct device *dev){	if (!matches || !dev->of_node || dev_of_node_reused(dev))		return NULL;	return of_match_node(matches, dev->of_node);}EXPORT_SYMBOL(of_match_device); static voidof_dma_set_restricted_buffer(struct device *dev, struct device_node *np){	struct device_node *of_node = dev->of_node;	struct of_phandle_iterator it;	int rc, i = 0; 	if (!IS_ENABLED(CONFIG_DMA_RESTRICTED_POOL))		return; 	/*	 * If dev->of_node doesn't exist or doesn't contain memory-region, try	 * the OF node having DMA configuration.	 */	if (!of_property_present(of_node, "memory-region"))		of_node = np; 	of_for_each_phandle(&it, rc, of_node, "memory-region", NULL, 0) {		/*		 * There might be multiple memory regions, but only one		 * restricted-dma-pool region is allowed.		 */		if (of_device_is_compatible(it.node, "restricted-dma-pool") &&		    of_device_is_available(it.node)) {			if (of_reserved_mem_device_init_by_idx(dev, of_node, i))				dev_warn(dev, "failed to initialise \"restricted-dma-pool\" memory node\n");			of_node_put(it.node);			break;		}		i++;	} } /** * of_dma_configure_id - Setup DMA configuration * @dev:	Device to apply DMA configuration * @np:		Pointer to OF node having DMA configuration * @force_dma:  Whether device is to be set up by of_dma_configure() even if *		DMA capability is not explicitly described by firmware. * @id:		Optional const pointer value input id * * Try to get devices's DMA configuration from DT and update it * accordingly. * * If platform code needs to use its own special DMA configuration, it * can use a platform bus notifier and handle BUS_NOTIFY_ADD_DEVICE events * to fix up DMA configuration. */int of_dma_configure_id(struct device *dev, struct device_node *np,			bool force_dma, const u32 *id){	const struct bus_dma_region *map = NULL;	struct device_node *bus_np;	u64 mask, end = 0;	bool coherent, set_map = false;	int ret; 	if (dev->dma_range_map) {		dev_dbg(dev, "dma_range_map already set\n");		goto skip_map;	} 	if (np == dev->of_node)		bus_np = __of_get_dma_parent(np);	else		bus_np = of_node_get(np); 	ret = of_dma_get_range(bus_np, &map);	of_node_put(bus_np);	if (ret < 0) {		/*		 * For legacy reasons, we have to assume some devices need		 * DMA configuration regardless of whether "dma-ranges" is		 * correctly specified or not.		 */		if (!force_dma)			return ret == -ENODEV ? 0 : ret;	} else {		/* Determine the overall bounds of all DMA regions */		end = dma_range_map_max(map);		set_map = true;	}skip_map:	/*	 * If @dev is expected to be DMA-capable then the bus code that created	 * it should have initialised its dma_mask pointer by this point. For	 * now, we'll continue the legacy behaviour of coercing it to the	 * coherent mask if not, but we'll no longer do so quietly.	 */	if (!dev->dma_mask) {		dev_warn(dev, "DMA mask not set\n");		dev->dma_mask = &dev->coherent_dma_mask;	} 	if (!end && dev->coherent_dma_mask)		end = dev->coherent_dma_mask;	else if (!end)		end = (1ULL << 32) - 1; 	/*	 * Limit coherent and dma mask based on size and default mask	 * set by the driver.	 */	mask = DMA_BIT_MASK(ilog2(end) + 1);	dev->coherent_dma_mask &= mask;	*dev->dma_mask &= mask;	/* ...but only set bus limit and range map if we found valid dma-ranges earlier */	if (set_map) {		dev->bus_dma_limit = end;		dev->dma_range_map = map;	} 	coherent = of_dma_is_coherent(np);	dev_dbg(dev, "device is%sdma coherent\n",		coherent ? " " : " not "); 	ret = of_iommu_configure(dev, np, id);	if (ret == -EPROBE_DEFER) {		/* Don't touch range map if it wasn't set from a valid dma-ranges */		if (set_map)			dev->dma_range_map = NULL;		kfree(map);		return -EPROBE_DEFER;	}	/* Take all other IOMMU errors to mean we'll just carry on without it */	dev_dbg(dev, "device is%sbehind an iommu\n",		!ret ? " " : " not "); 	arch_setup_dma_ops(dev, coherent); 	if (ret)		of_dma_set_restricted_buffer(dev, np); 	return 0;}EXPORT_SYMBOL_GPL(of_dma_configure_id); const void *of_device_get_match_data(const struct device *dev){	const struct of_device_id *match; 	match = of_match_device(dev->driver->of_match_table, dev);	if (!match)		return NULL; 	return match->data;}EXPORT_SYMBOL(of_device_get_match_data); /** * of_device_modalias - Fill buffer with newline terminated modalias string * @dev:	Calling device * @str:	Modalias string * @len:	Size of @str */ssize_t of_device_modalias(struct device *dev, char *str, ssize_t len){	ssize_t sl; 	if (!dev || !dev->of_node || dev_of_node_reused(dev))		return -ENODEV; 	sl = of_modalias(dev->of_node, str, len - 2);	if (sl < 0)		return sl;	if (sl > len - 2)		return -ENOMEM; 	str[sl++] = '\n';	str[sl] = 0;	return sl;}EXPORT_SYMBOL_GPL(of_device_modalias); /** * of_device_uevent - Display OF related uevent information * @dev:	Device to display the uevent information for * @env:	Kernel object's userspace event reference to fill up */void of_device_uevent(const struct device *dev, struct kobj_uevent_env *env){	const char *compat, *type;	struct alias_prop *app;	struct property *p;	int seen = 0; 	if ((!dev) || (!dev->of_node))		return; 	add_uevent_var(env, "OF_NAME=%pOFn", dev->of_node);	add_uevent_var(env, "OF_FULLNAME=%pOF", dev->of_node);	type = of_node_get_device_type(dev->of_node);	if (type)		add_uevent_var(env, "OF_TYPE=%s", type); 	/* Since the compatible field can contain pretty much anything	 * it's not really legal to split it out with commas. We split it	 * up using a number of environment variables instead. */	of_property_for_each_string(dev->of_node, "compatible", p, compat) {		add_uevent_var(env, "OF_COMPATIBLE_%d=%s", seen, compat);		seen++;	}	add_uevent_var(env, "OF_COMPATIBLE_N=%d", seen); 	seen = 0;	mutex_lock(&of_mutex);	list_for_each_entry(app, &aliases_lookup, link) {		if (dev->of_node == app->np) {			add_uevent_var(env, "OF_ALIAS_%d=%s", seen,				       app->alias);			seen++;		}	}	mutex_unlock(&of_mutex);}EXPORT_SYMBOL_GPL(of_device_uevent); int of_device_uevent_modalias(const struct device *dev, struct kobj_uevent_env *env){	int sl; 	if ((!dev) || (!dev->of_node) || dev_of_node_reused(dev))		return -ENODEV; 	/* Devicetree modalias is tricky, we add it in 2 steps */	if (add_uevent_var(env, "MODALIAS="))		return -ENOMEM; 	sl = of_modalias(dev->of_node, &env->buf[env->buflen-1],			 sizeof(env->buf) - env->buflen);	if (sl < 0)		return sl;	if (sl >= (sizeof(env->buf) - env->buflen))		return -ENOMEM;	env->buflen += sl; 	return 0;}EXPORT_SYMBOL_GPL(of_device_uevent_modalias); /** * of_device_make_bus_id - Use the device node data to assign a unique name * @dev: pointer to device structure that is linked to a device tree node * * This routine will first try using the translated bus address to * derive a unique name. If it cannot, then it will prepend names from * parent nodes until a unique name can be derived. */void of_device_make_bus_id(struct device *dev){	struct device_node *node = dev->of_node;	const __be32 *reg;	u64 addr;	u32 mask; 	/* Construct the name, using parent nodes if necessary to ensure uniqueness */	while (node->parent) {		/*		 * If the address can be translated, then that is as much		 * uniqueness as we need. Make it the first component and return		 */		reg = of_get_property(node, "reg", NULL);		if (reg && (addr = of_translate_address(node, reg)) != OF_BAD_ADDR) {			if (!of_property_read_u32(node, "mask", &mask))				dev_set_name(dev, dev_name(dev) ? "%llx.%x.%pOFn:%s" : "%llx.%x.%pOFn",					     addr, ffs(mask) - 1, node, dev_name(dev)); 			else				dev_set_name(dev, dev_name(dev) ? "%llx.%pOFn:%s" : "%llx.%pOFn",					     addr, node, dev_name(dev));			return;		} 		/* format arguments only used if dev_name() resolves to NULL */		dev_set_name(dev, dev_name(dev) ? "%s:%s" : "%s",			     kbasename(node->full_name), dev_name(dev));		node = node->parent;	}}EXPORT_SYMBOL_GPL(of_device_make_bus_id);