coresight: Support for ACPI bindings

 * 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>

}

#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. */

const union acpi_object *

acpi_get_dsd_graph(struct acpi_device *adev)

{

	int i;

	struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };

	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.

 */

const union acpi_object *

acpi_get_coresight_graph(struct acpi_device *adev)

{

	const union acpi_object *graph_list, *graph;

	int i, nr_graphs;

	graph_list = acpi_get_dsd_graph(adev);

	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 rc, 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;

	rc = acpi_bus_get_device(fields[2].reference.handle, &r_adev);

	if (rc)

		return rc;

	dir = fields[3].integer.value;

	if (dir == ACPI_CORESIGHT_LINK_MASTER) {

		conn->outport = fields[0].integer.value;

		conn->child_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->child_fwnode = fwnode_handle_get(&r_adev->fwnode);

	}

	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 acpi_device *adev,

				      struct coresight_platform_data *pdata)

{

	int rc, i, nlinks;

	const union acpi_object *graph;

	struct coresight_connection *conns, *ptr;

	pdata->nr_inport = pdata->nr_outport = 0;

	graph = acpi_get_coresight_graph(adev);

	if (!graph)

		return -ENOENT;

	nlinks = graph->package.elements[2].integer.value;

	if (!nlinks)

		return 0;

	/*

	 * To avoid scanning the table twice (once for finding the number of

	 * output links and then later for parsing the output links),

	 * cache the links information in one go and then later copy

	 * it to the pdata.

	 */

	conns = devm_kcalloc(&adev->dev, nlinks, sizeof(*conns), GFP_KERNEL);

	if (!conns)

		return -ENOMEM;

	ptr = conns;

	for (i = 0; i < nlinks; i++) {

		const union acpi_object *link = &graph->package.elements[3 + i];

		int dir;

		dir = acpi_coresight_parse_link(adev, link, ptr);

		if (dir < 0)

			return dir;

		if (dir == ACPI_CORESIGHT_LINK_MASTER) {

			pdata->nr_outport++;

			ptr++;

		} else {

			pdata->nr_inport++;

		}

	}

	rc = coresight_alloc_conns(&adev->dev, pdata);

	if (rc)

		return rc;

	/* Copy the connection information to the final location */

	for (i = 0; i < pdata->nr_outport; i++)

		pdata->conns[i] = conns[i];

	devm_kfree(&adev->dev, conns);

	return 0;

}

/*

 * 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 0;

	status = acpi_get_parent(adev->handle, &cpu_handle);

	if (ACPI_FAILURE(status))

		return 0;

	cpu = acpi_handle_to_logical_cpuid(cpu_handle);

	if (cpu >= nr_cpu_ids)

		return 0;

	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(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 0;

}

#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);

	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;