1 files changed, 314 insertions, 0 deletions
diff --git a/drivers/of/device.c b/drivers/of/device.c
new file mode 100644
index 000000000..b3dc78f2f
--- /dev/null
+++ b/drivers/of/device.c
@@ -0,0 +1,314 @@
+// 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 void
+of_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);