1 files changed, 306 insertions, 0 deletions
diff --git a/drivers/of/device.c b/drivers/of/device.c
new file mode 100644
index 0000000000..1ca42ad9dd
--- /dev/null
+++ b/drivers/of/device.c
@@ -0,0 +1,306 @@
+// 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/mod_devicetable.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 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)
+		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 *node, *of_node = dev->of_node;
+	int count, i;
+
+	if (!IS_ENABLED(CONFIG_DMA_RESTRICTED_POOL))
+		return;
+
+	count = of_property_count_elems_of_size(of_node, "memory-region",
+						sizeof(u32));
+	/*
+	 * If dev->of_node doesn't exist or doesn't contain memory-region, try
+	 * the OF node having DMA configuration.
+	 */
+	if (count <= 0) {
+		of_node = np;
+		count = of_property_count_elems_of_size(
+			of_node, "memory-region", sizeof(u32));
+	}
+
+	for (i = 0; i < count; i++) {
+		node = of_parse_phandle(of_node, "memory-region", i);
+		/*
+		 * There might be multiple memory regions, but only one
+		 * restricted-dma-pool region is allowed.
+		 */
+		if (of_device_is_compatible(node, "restricted-dma-pool") &&
+		    of_device_is_available(node)) {
+			of_node_put(node);
+			break;
+		}
+		of_node_put(node);
+	}
+
+	/*
+	 * Attempt to initialize a restricted-dma-pool region if one was found.
+	 * Note that count can hold a negative error code.
+	 */
+	if (i < count && of_reserved_mem_device_init_by_idx(dev, of_node, i))
+		dev_warn(dev, "failed to initialise \"restricted-dma-pool\" memory node\n");
+}
+
+/**
+ * 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 iommu_ops *iommu;
+	const struct bus_dma_region *map = NULL;
+	struct device_node *bus_np;
+	u64 dma_start = 0;
+	u64 mask, end, size = 0;
+	bool coherent;
+	int ret;
+
+	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 {
+		const struct bus_dma_region *r = map;
+		u64 dma_end = 0;
+
+		/* Determine the overall bounds of all DMA regions */
+		for (dma_start = ~0; r->size; r++) {
+			/* Take lower and upper limits */
+			if (r->dma_start < dma_start)
+				dma_start = r->dma_start;
+			if (r->dma_start + r->size > dma_end)
+				dma_end = r->dma_start + r->size;
+		}
+		size = dma_end - dma_start;
+
+		/*
+		 * Add a work around to treat the size as mask + 1 in case
+		 * it is defined in DT as a mask.
+		 */
+		if (size & 1) {
+			dev_warn(dev, "Invalid size 0x%llx for dma-range(s)\n",
+				 size);
+			size = size + 1;
+		}
+
+		if (!size) {
+			dev_err(dev, "Adjusted size 0x%llx invalid\n", size);
+			kfree(map);
+			return -EINVAL;
+		}
+	}
+
+	/*
+	 * 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 (!size && dev->coherent_dma_mask)
+		size = max(dev->coherent_dma_mask, dev->coherent_dma_mask + 1);
+	else if (!size)
+		size = 1ULL << 32;
+
+	/*
+	 * Limit coherent and dma mask based on size and default mask
+	 * set by the driver.
+	 */
+	end = dma_start + size - 1;
+	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 (!ret) {
+		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 ");
+
+	iommu = of_iommu_configure(dev, np, id);
+	if (PTR_ERR(iommu) == -EPROBE_DEFER) {
+		/* Don't touch range map if it wasn't set from a valid dma-ranges */
+		if (!ret)
+			dev->dma_range_map = NULL;
+		kfree(map);
+		return -EPROBE_DEFER;
+	}
+
+	dev_dbg(dev, "device is%sbehind an iommu\n",
+		iommu ? " " : " not ");
+
+	arch_setup_dma_ops(dev, dma_start, size, iommu, coherent);
+
+	if (!iommu)
+		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)
+		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)
+		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);