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-rw-r--r--drivers/hwtracing/coresight/coresight-platform.c826
1 files changed, 826 insertions, 0 deletions
diff --git a/drivers/hwtracing/coresight/coresight-platform.c b/drivers/hwtracing/coresight/coresight-platform.c
new file mode 100644
index 0000000000..9d550f5697
--- /dev/null
+++ b/drivers/hwtracing/coresight/coresight-platform.c
@@ -0,0 +1,826 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2012, The Linux Foundation. All rights reserved.
+ */
+
+#include <linux/acpi.h>
+#include <linux/types.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/clk.h>
+#include <linux/of.h>
+#include <linux/of_graph.h>
+#include <linux/platform_device.h>
+#include <linux/amba/bus.h>
+#include <linux/coresight.h>
+#include <linux/cpumask.h>
+#include <asm/smp_plat.h>
+
+#include "coresight-priv.h"
+
+/*
+ * Add an entry to the connection list and assign @conn's contents to it.
+ *
+ * If the output port is already assigned on this device, return -EINVAL
+ */
+struct coresight_connection *
+coresight_add_out_conn(struct device *dev,
+ struct coresight_platform_data *pdata,
+ const struct coresight_connection *new_conn)
+{
+ int i;
+ struct coresight_connection *conn;
+
+ /*
+ * Warn on any existing duplicate output port.
+ */
+ for (i = 0; i < pdata->nr_outconns; ++i) {
+ conn = pdata->out_conns[i];
+ /* Output == -1 means ignore the port for example for helpers */
+ if (conn->src_port != -1 &&
+ conn->src_port == new_conn->src_port) {
+ dev_warn(dev, "Duplicate output port %d\n",
+ conn->src_port);
+ return ERR_PTR(-EINVAL);
+ }
+ }
+
+ pdata->nr_outconns++;
+ pdata->out_conns =
+ devm_krealloc_array(dev, pdata->out_conns, pdata->nr_outconns,
+ sizeof(*pdata->out_conns), GFP_KERNEL);
+ if (!pdata->out_conns)
+ return ERR_PTR(-ENOMEM);
+
+ conn = devm_kmalloc(dev, sizeof(struct coresight_connection),
+ GFP_KERNEL);
+ if (!conn)
+ return ERR_PTR(-ENOMEM);
+
+ /*
+ * Copy the new connection into the allocation, save the pointer to the
+ * end of the connection array and also return it in case it needs to be
+ * used right away.
+ */
+ *conn = *new_conn;
+ pdata->out_conns[pdata->nr_outconns - 1] = conn;
+ return conn;
+}
+EXPORT_SYMBOL_GPL(coresight_add_out_conn);
+
+/*
+ * Add an input connection reference to @out_conn in the target's in_conns array
+ *
+ * @out_conn: Existing output connection to store as an input on the
+ * connection's remote device.
+ */
+int coresight_add_in_conn(struct coresight_connection *out_conn)
+{
+ int i;
+ struct device *dev = out_conn->dest_dev->dev.parent;
+ struct coresight_platform_data *pdata = out_conn->dest_dev->pdata;
+
+ for (i = 0; i < pdata->nr_inconns; ++i)
+ if (!pdata->in_conns[i]) {
+ pdata->in_conns[i] = out_conn;
+ return 0;
+ }
+
+ pdata->nr_inconns++;
+ pdata->in_conns =
+ devm_krealloc_array(dev, pdata->in_conns, pdata->nr_inconns,
+ sizeof(*pdata->in_conns), GFP_KERNEL);
+ if (!pdata->in_conns)
+ return -ENOMEM;
+ pdata->in_conns[pdata->nr_inconns - 1] = out_conn;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(coresight_add_in_conn);
+
+static struct device *
+coresight_find_device_by_fwnode(struct fwnode_handle *fwnode)
+{
+ struct device *dev = NULL;
+
+ /*
+ * If we have a non-configurable replicator, it will be found on the
+ * platform bus.
+ */
+ dev = bus_find_device_by_fwnode(&platform_bus_type, fwnode);
+ if (dev)
+ return dev;
+
+ /*
+ * We have a configurable component - circle through the AMBA bus
+ * looking for the device that matches the endpoint node.
+ */
+ return bus_find_device_by_fwnode(&amba_bustype, fwnode);
+}
+
+/*
+ * Find a registered coresight device from a device fwnode.
+ * The node info is associated with the AMBA parent, but the
+ * csdev keeps a copy so iterate round the coresight bus to
+ * find the device.
+ */
+struct coresight_device *
+coresight_find_csdev_by_fwnode(struct fwnode_handle *r_fwnode)
+{
+ struct device *dev;
+ struct coresight_device *csdev = NULL;
+
+ dev = bus_find_device_by_fwnode(&coresight_bustype, r_fwnode);
+ if (dev) {
+ csdev = to_coresight_device(dev);
+ put_device(dev);
+ }
+ return csdev;
+}
+EXPORT_SYMBOL_GPL(coresight_find_csdev_by_fwnode);
+
+#ifdef CONFIG_OF
+static inline bool of_coresight_legacy_ep_is_input(struct device_node *ep)
+{
+ return of_property_read_bool(ep, "slave-mode");
+}
+
+static struct device_node *of_coresight_get_port_parent(struct device_node *ep)
+{
+ struct device_node *parent = of_graph_get_port_parent(ep);
+
+ /*
+ * Skip one-level up to the real device node, if we
+ * are using the new bindings.
+ */
+ if (of_node_name_eq(parent, "in-ports") ||
+ of_node_name_eq(parent, "out-ports"))
+ parent = of_get_next_parent(parent);
+
+ return parent;
+}
+
+static inline struct device_node *
+of_coresight_get_output_ports_node(const struct device_node *node)
+{
+ return of_get_child_by_name(node, "out-ports");
+}
+
+static int of_coresight_get_cpu(struct device *dev)
+{
+ int cpu;
+ struct device_node *dn;
+
+ if (!dev->of_node)
+ return -ENODEV;
+
+ dn = of_parse_phandle(dev->of_node, "cpu", 0);
+ if (!dn)
+ return -ENODEV;
+
+ cpu = of_cpu_node_to_id(dn);
+ of_node_put(dn);
+
+ return cpu;
+}
+
+/*
+ * of_coresight_parse_endpoint : Parse the given output endpoint @ep
+ * and fill the connection information in @pdata->out_conns
+ *
+ * Parses the local port, remote device name and the remote port.
+ *
+ * Returns :
+ * 0 - If the parsing completed without any fatal errors.
+ * -Errno - Fatal error, abort the scanning.
+ */
+static int of_coresight_parse_endpoint(struct device *dev,
+ struct device_node *ep,
+ struct coresight_platform_data *pdata)
+{
+ int ret = 0;
+ struct of_endpoint endpoint, rendpoint;
+ struct device_node *rparent = NULL;
+ struct device_node *rep = NULL;
+ struct device *rdev = NULL;
+ struct fwnode_handle *rdev_fwnode;
+ struct coresight_connection conn = {};
+ struct coresight_connection *new_conn;
+
+ do {
+ /* Parse the local port details */
+ if (of_graph_parse_endpoint(ep, &endpoint))
+ break;
+ /*
+ * Get a handle on the remote endpoint and the device it is
+ * attached to.
+ */
+ rep = of_graph_get_remote_endpoint(ep);
+ if (!rep)
+ break;
+ rparent = of_coresight_get_port_parent(rep);
+ if (!rparent)
+ break;
+ if (of_graph_parse_endpoint(rep, &rendpoint))
+ break;
+
+ rdev_fwnode = of_fwnode_handle(rparent);
+ /* If the remote device is not available, defer probing */
+ rdev = coresight_find_device_by_fwnode(rdev_fwnode);
+ if (!rdev) {
+ ret = -EPROBE_DEFER;
+ break;
+ }
+
+ conn.src_port = endpoint.port;
+ /*
+ * Hold the refcount to the target device. This could be
+ * released via:
+ * 1) coresight_release_platform_data() if the probe fails or
+ * this device is unregistered.
+ * 2) While removing the target device via
+ * coresight_remove_match()
+ */
+ conn.dest_fwnode = fwnode_handle_get(rdev_fwnode);
+ conn.dest_port = rendpoint.port;
+
+ new_conn = coresight_add_out_conn(dev, pdata, &conn);
+ if (IS_ERR_VALUE(new_conn)) {
+ fwnode_handle_put(conn.dest_fwnode);
+ return PTR_ERR(new_conn);
+ }
+ /* Connection record updated */
+ } while (0);
+
+ of_node_put(rparent);
+ of_node_put(rep);
+ put_device(rdev);
+
+ return ret;
+}
+
+static int of_get_coresight_platform_data(struct device *dev,
+ struct coresight_platform_data *pdata)
+{
+ int ret = 0;
+ struct device_node *ep = NULL;
+ const struct device_node *parent = NULL;
+ bool legacy_binding = false;
+ struct device_node *node = dev->of_node;
+
+ parent = of_coresight_get_output_ports_node(node);
+ /*
+ * If the DT uses obsoleted bindings, the ports are listed
+ * under the device and we need to filter out the input
+ * ports.
+ */
+ if (!parent) {
+ /*
+ * Avoid warnings in of_graph_get_next_endpoint()
+ * if the device doesn't have any graph connections
+ */
+ if (!of_graph_is_present(node))
+ return 0;
+ legacy_binding = true;
+ parent = node;
+ dev_warn_once(dev, "Uses obsolete Coresight DT bindings\n");
+ }
+
+ /* Iterate through each output port to discover topology */
+ while ((ep = of_graph_get_next_endpoint(parent, ep))) {
+ /*
+ * Legacy binding mixes input/output ports under the
+ * same parent. So, skip the input ports if we are dealing
+ * with legacy binding, as they processed with their
+ * connected output ports.
+ */
+ if (legacy_binding && of_coresight_legacy_ep_is_input(ep))
+ continue;
+
+ ret = of_coresight_parse_endpoint(dev, ep, pdata);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+#else
+static inline int
+of_get_coresight_platform_data(struct device *dev,
+ struct coresight_platform_data *pdata)
+{
+ return -ENOENT;
+}
+
+static inline int of_coresight_get_cpu(struct device *dev)
+{
+ return -ENODEV;
+}
+#endif
+
+#ifdef CONFIG_ACPI
+
+#include <acpi/actypes.h>
+#include <acpi/processor.h>
+
+/* ACPI Graph _DSD UUID : "ab02a46b-74c7-45a2-bd68-f7d344ef2153" */
+static const guid_t acpi_graph_uuid = GUID_INIT(0xab02a46b, 0x74c7, 0x45a2,
+ 0xbd, 0x68, 0xf7, 0xd3,
+ 0x44, 0xef, 0x21, 0x53);
+/* Coresight ACPI Graph UUID : "3ecbc8b6-1d0e-4fb3-8107-e627f805c6cd" */
+static const guid_t coresight_graph_uuid = GUID_INIT(0x3ecbc8b6, 0x1d0e, 0x4fb3,
+ 0x81, 0x07, 0xe6, 0x27,
+ 0xf8, 0x05, 0xc6, 0xcd);
+#define ACPI_CORESIGHT_LINK_SLAVE 0
+#define ACPI_CORESIGHT_LINK_MASTER 1
+
+static inline bool is_acpi_guid(const union acpi_object *obj)
+{
+ return (obj->type == ACPI_TYPE_BUFFER) && (obj->buffer.length == 16);
+}
+
+/*
+ * acpi_guid_matches - Checks if the given object is a GUID object and
+ * that it matches the supplied the GUID.
+ */
+static inline bool acpi_guid_matches(const union acpi_object *obj,
+ const guid_t *guid)
+{
+ return is_acpi_guid(obj) &&
+ guid_equal((guid_t *)obj->buffer.pointer, guid);
+}
+
+static inline bool is_acpi_dsd_graph_guid(const union acpi_object *obj)
+{
+ return acpi_guid_matches(obj, &acpi_graph_uuid);
+}
+
+static inline bool is_acpi_coresight_graph_guid(const union acpi_object *obj)
+{
+ return acpi_guid_matches(obj, &coresight_graph_uuid);
+}
+
+static inline bool is_acpi_coresight_graph(const union acpi_object *obj)
+{
+ const union acpi_object *graphid, *guid, *links;
+
+ if (obj->type != ACPI_TYPE_PACKAGE ||
+ obj->package.count < 3)
+ return false;
+
+ graphid = &obj->package.elements[0];
+ guid = &obj->package.elements[1];
+ links = &obj->package.elements[2];
+
+ if (graphid->type != ACPI_TYPE_INTEGER ||
+ links->type != ACPI_TYPE_INTEGER)
+ return false;
+
+ return is_acpi_coresight_graph_guid(guid);
+}
+
+/*
+ * acpi_validate_dsd_graph - Make sure the given _DSD graph conforms
+ * to the ACPI _DSD Graph specification.
+ *
+ * ACPI Devices Graph property has the following format:
+ * {
+ * Revision - Integer, must be 0
+ * NumberOfGraphs - Integer, N indicating the following list.
+ * Graph[1],
+ * ...
+ * Graph[N]
+ * }
+ *
+ * And each Graph entry has the following format:
+ * {
+ * GraphID - Integer, identifying a graph the device belongs to.
+ * UUID - UUID identifying the specification that governs
+ * this graph. (e.g, see is_acpi_coresight_graph())
+ * NumberOfLinks - Number "N" of connections on this node of the graph.
+ * Links[1]
+ * ...
+ * Links[N]
+ * }
+ *
+ * Where each "Links" entry has the following format:
+ *
+ * {
+ * SourcePortAddress - Integer
+ * DestinationPortAddress - Integer
+ * DestinationDeviceName - Reference to another device
+ * ( --- CoreSight specific extensions below ---)
+ * DirectionOfFlow - Integer 1 for output(master)
+ * 0 for input(slave)
+ * }
+ *
+ * e.g:
+ * For a Funnel device
+ *
+ * Device(MFUN) {
+ * ...
+ *
+ * Name (_DSD, Package() {
+ * // DSD Package contains tuples of { Proeprty_Type_UUID, Package() }
+ * ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), //Std. Property UUID
+ * Package() {
+ * Package(2) { "property-name", <property-value> }
+ * },
+ *
+ * ToUUID("ab02a46b-74c7-45a2-bd68-f7d344ef2153"), // ACPI Graph UUID
+ * Package() {
+ * 0, // Revision
+ * 1, // NumberOfGraphs.
+ * Package() { // Graph[0] Package
+ * 1, // GraphID
+ * // Coresight Graph UUID
+ * ToUUID("3ecbc8b6-1d0e-4fb3-8107-e627f805c6cd"),
+ * 3, // NumberOfLinks aka ports
+ * // Link[0]: Output_0 -> Replicator:Input_0
+ * Package () { 0, 0, \_SB_.RPL0, 1 },
+ * // Link[1]: Input_0 <- Cluster0_Funnel0:Output_0
+ * Package () { 0, 0, \_SB_.CLU0.FUN0, 0 },
+ * // Link[2]: Input_1 <- Cluster1_Funnel0:Output_0
+ * Package () { 1, 0, \_SB_.CLU1.FUN0, 0 },
+ * } // End of Graph[0] Package
+ *
+ * }, // End of ACPI Graph Property
+ * })
+ */
+static inline bool acpi_validate_dsd_graph(const union acpi_object *graph)
+{
+ int i, n;
+ const union acpi_object *rev, *nr_graphs;
+
+ /* The graph must contain at least the Revision and Number of Graphs */
+ if (graph->package.count < 2)
+ return false;
+
+ rev = &graph->package.elements[0];
+ nr_graphs = &graph->package.elements[1];
+
+ if (rev->type != ACPI_TYPE_INTEGER ||
+ nr_graphs->type != ACPI_TYPE_INTEGER)
+ return false;
+
+ /* We only support revision 0 */
+ if (rev->integer.value != 0)
+ return false;
+
+ n = nr_graphs->integer.value;
+ /* CoreSight devices are only part of a single Graph */
+ if (n != 1)
+ return false;
+
+ /* Make sure the ACPI graph package has right number of elements */
+ if (graph->package.count != (n + 2))
+ return false;
+
+ /*
+ * Each entry must be a graph package with at least 3 members :
+ * { GraphID, UUID, NumberOfLinks(n), Links[.],... }
+ */
+ for (i = 2; i < n + 2; i++) {
+ const union acpi_object *obj = &graph->package.elements[i];
+
+ if (obj->type != ACPI_TYPE_PACKAGE ||
+ obj->package.count < 3)
+ return false;
+ }
+
+ return true;
+}
+
+/* acpi_get_dsd_graph - Find the _DSD Graph property for the given device. */
+static const union acpi_object *
+acpi_get_dsd_graph(struct acpi_device *adev, struct acpi_buffer *buf)
+{
+ int i;
+ acpi_status status;
+ const union acpi_object *dsd;
+
+ status = acpi_evaluate_object_typed(adev->handle, "_DSD", NULL,
+ buf, ACPI_TYPE_PACKAGE);
+ if (ACPI_FAILURE(status))
+ return NULL;
+
+ dsd = buf->pointer;
+
+ /*
+ * _DSD property consists tuples { Prop_UUID, Package() }
+ * Iterate through all the packages and find the Graph.
+ */
+ for (i = 0; i + 1 < dsd->package.count; i += 2) {
+ const union acpi_object *guid, *package;
+
+ guid = &dsd->package.elements[i];
+ package = &dsd->package.elements[i + 1];
+
+ /* All _DSD elements must have a UUID and a Package */
+ if (!is_acpi_guid(guid) || package->type != ACPI_TYPE_PACKAGE)
+ break;
+ /* Skip the non-Graph _DSD packages */
+ if (!is_acpi_dsd_graph_guid(guid))
+ continue;
+ if (acpi_validate_dsd_graph(package))
+ return package;
+ /* Invalid graph format, continue */
+ dev_warn(&adev->dev, "Invalid Graph _DSD property\n");
+ }
+
+ return NULL;
+}
+
+static inline bool
+acpi_validate_coresight_graph(const union acpi_object *cs_graph)
+{
+ int nlinks;
+
+ nlinks = cs_graph->package.elements[2].integer.value;
+ /*
+ * Graph must have the following fields :
+ * { GraphID, GraphUUID, NumberOfLinks, Links... }
+ */
+ if (cs_graph->package.count != (nlinks + 3))
+ return false;
+ /* The links are validated in acpi_coresight_parse_link() */
+ return true;
+}
+
+/*
+ * acpi_get_coresight_graph - Parse the device _DSD tables and find
+ * the Graph property matching the CoreSight Graphs.
+ *
+ * Returns the pointer to the CoreSight Graph Package when found. Otherwise
+ * returns NULL.
+ */
+static const union acpi_object *
+acpi_get_coresight_graph(struct acpi_device *adev, struct acpi_buffer *buf)
+{
+ const union acpi_object *graph_list, *graph;
+ int i, nr_graphs;
+
+ graph_list = acpi_get_dsd_graph(adev, buf);
+ if (!graph_list)
+ return graph_list;
+
+ nr_graphs = graph_list->package.elements[1].integer.value;
+
+ for (i = 2; i < nr_graphs + 2; i++) {
+ graph = &graph_list->package.elements[i];
+ if (!is_acpi_coresight_graph(graph))
+ continue;
+ if (acpi_validate_coresight_graph(graph))
+ return graph;
+ /* Invalid graph format */
+ break;
+ }
+
+ return NULL;
+}
+
+/*
+ * acpi_coresight_parse_link - Parse the given Graph connection
+ * of the device and populate the coresight_connection for an output
+ * connection.
+ *
+ * CoreSight Graph specification mandates that the direction of the data
+ * flow must be specified in the link. i.e,
+ *
+ * SourcePortAddress, // Integer
+ * DestinationPortAddress, // Integer
+ * DestinationDeviceName, // Reference to another device
+ * DirectionOfFlow, // 1 for output(master), 0 for input(slave)
+ *
+ * Returns the direction of the data flow [ Input(slave) or Output(master) ]
+ * upon success.
+ * Returns an negative error number otherwise.
+ */
+static int acpi_coresight_parse_link(struct acpi_device *adev,
+ const union acpi_object *link,
+ struct coresight_connection *conn)
+{
+ int dir;
+ const union acpi_object *fields;
+ struct acpi_device *r_adev;
+ struct device *rdev;
+
+ if (link->type != ACPI_TYPE_PACKAGE ||
+ link->package.count != 4)
+ return -EINVAL;
+
+ fields = link->package.elements;
+
+ if (fields[0].type != ACPI_TYPE_INTEGER ||
+ fields[1].type != ACPI_TYPE_INTEGER ||
+ fields[2].type != ACPI_TYPE_LOCAL_REFERENCE ||
+ fields[3].type != ACPI_TYPE_INTEGER)
+ return -EINVAL;
+
+ r_adev = acpi_fetch_acpi_dev(fields[2].reference.handle);
+ if (!r_adev)
+ return -ENODEV;
+
+ dir = fields[3].integer.value;
+ if (dir == ACPI_CORESIGHT_LINK_MASTER) {
+ conn->src_port = fields[0].integer.value;
+ conn->dest_port = fields[1].integer.value;
+ rdev = coresight_find_device_by_fwnode(&r_adev->fwnode);
+ if (!rdev)
+ return -EPROBE_DEFER;
+ /*
+ * Hold the refcount to the target device. This could be
+ * released via:
+ * 1) coresight_release_platform_data() if the probe fails or
+ * this device is unregistered.
+ * 2) While removing the target device via
+ * coresight_remove_match().
+ */
+ conn->dest_fwnode = fwnode_handle_get(&r_adev->fwnode);
+ } else if (dir == ACPI_CORESIGHT_LINK_SLAVE) {
+ /*
+ * We are only interested in the port number
+ * for the input ports at this component.
+ * Store the port number in child_port.
+ */
+ conn->dest_port = fields[0].integer.value;
+ } else {
+ /* Invalid direction */
+ return -EINVAL;
+ }
+
+ return dir;
+}
+
+/*
+ * acpi_coresight_parse_graph - Parse the _DSD CoreSight graph
+ * connection information and populate the supplied coresight_platform_data
+ * instance.
+ */
+static int acpi_coresight_parse_graph(struct device *dev,
+ struct acpi_device *adev,
+ struct coresight_platform_data *pdata)
+{
+ int ret = 0;
+ int i, nlinks;
+ const union acpi_object *graph;
+ struct coresight_connection conn, zero_conn = {};
+ struct coresight_connection *new_conn;
+ struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER, NULL };
+
+ graph = acpi_get_coresight_graph(adev, &buf);
+ /*
+ * There are no graph connections, which is fine for some components.
+ * e.g., ETE
+ */
+ if (!graph)
+ goto free;
+
+ nlinks = graph->package.elements[2].integer.value;
+ if (!nlinks)
+ goto free;
+
+ for (i = 0; i < nlinks; i++) {
+ const union acpi_object *link = &graph->package.elements[3 + i];
+ int dir;
+
+ conn = zero_conn;
+ dir = acpi_coresight_parse_link(adev, link, &conn);
+ if (dir < 0) {
+ ret = dir;
+ goto free;
+ }
+
+ if (dir == ACPI_CORESIGHT_LINK_MASTER) {
+ new_conn = coresight_add_out_conn(dev, pdata, &conn);
+ if (IS_ERR(new_conn)) {
+ ret = PTR_ERR(new_conn);
+ goto free;
+ }
+ }
+ }
+
+free:
+ /*
+ * When ACPI fails to alloc a buffer, it will free the buffer
+ * created via ACPI_ALLOCATE_BUFFER and set to NULL.
+ * ACPI_FREE can handle NULL pointers, so free it directly.
+ */
+ ACPI_FREE(buf.pointer);
+ return ret;
+}
+
+/*
+ * acpi_handle_to_logical_cpuid - Map a given acpi_handle to the
+ * logical CPU id of the corresponding CPU device.
+ *
+ * Returns the logical CPU id when found. Otherwise returns >= nr_cpus_id.
+ */
+static int
+acpi_handle_to_logical_cpuid(acpi_handle handle)
+{
+ int i;
+ struct acpi_processor *pr;
+
+ for_each_possible_cpu(i) {
+ pr = per_cpu(processors, i);
+ if (pr && pr->handle == handle)
+ break;
+ }
+
+ return i;
+}
+
+/*
+ * acpi_coresigh_get_cpu - Find the logical CPU id of the CPU associated
+ * with this coresight device. With ACPI bindings, the CoreSight components
+ * are listed as child device of the associated CPU.
+ *
+ * Returns the logical CPU id when found. Otherwise returns 0.
+ */
+static int acpi_coresight_get_cpu(struct device *dev)
+{
+ int cpu;
+ acpi_handle cpu_handle;
+ acpi_status status;
+ struct acpi_device *adev = ACPI_COMPANION(dev);
+
+ if (!adev)
+ return -ENODEV;
+ status = acpi_get_parent(adev->handle, &cpu_handle);
+ if (ACPI_FAILURE(status))
+ return -ENODEV;
+
+ cpu = acpi_handle_to_logical_cpuid(cpu_handle);
+ if (cpu >= nr_cpu_ids)
+ return -ENODEV;
+ return cpu;
+}
+
+static int
+acpi_get_coresight_platform_data(struct device *dev,
+ struct coresight_platform_data *pdata)
+{
+ struct acpi_device *adev;
+
+ adev = ACPI_COMPANION(dev);
+ if (!adev)
+ return -EINVAL;
+
+ return acpi_coresight_parse_graph(dev, adev, pdata);
+}
+
+#else
+
+static inline int
+acpi_get_coresight_platform_data(struct device *dev,
+ struct coresight_platform_data *pdata)
+{
+ return -ENOENT;
+}
+
+static inline int acpi_coresight_get_cpu(struct device *dev)
+{
+ return -ENODEV;
+}
+#endif
+
+int coresight_get_cpu(struct device *dev)
+{
+ if (is_of_node(dev->fwnode))
+ return of_coresight_get_cpu(dev);
+ else if (is_acpi_device_node(dev->fwnode))
+ return acpi_coresight_get_cpu(dev);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(coresight_get_cpu);
+
+struct coresight_platform_data *
+coresight_get_platform_data(struct device *dev)
+{
+ int ret = -ENOENT;
+ struct coresight_platform_data *pdata = NULL;
+ struct fwnode_handle *fwnode = dev_fwnode(dev);
+
+ if (IS_ERR_OR_NULL(fwnode))
+ goto error;
+
+ pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
+ if (!pdata) {
+ ret = -ENOMEM;
+ goto error;
+ }
+
+ if (is_of_node(fwnode))
+ ret = of_get_coresight_platform_data(dev, pdata);
+ else if (is_acpi_device_node(fwnode))
+ ret = acpi_get_coresight_platform_data(dev, pdata);
+
+ if (!ret)
+ return pdata;
+error:
+ if (!IS_ERR_OR_NULL(pdata))
+ /* Cleanup the connection information */
+ coresight_release_platform_data(NULL, dev, pdata);
+ return ERR_PTR(ret);
+}
+EXPORT_SYMBOL_GPL(coresight_get_platform_data);