Commit 76ffa5ab authored by Suzuki K Poulose's avatar Suzuki K Poulose Committed by Greg Kroah-Hartman

coresight: Support for ACPI bindings

Add support for parsing the ACPI platform description
for CoreSight. The connections are encoded in a DSD graph
property with CoreSight specific variation of the property.

The ETMs are listed as the children device of the respective
CPU.

Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Signed-off-by: default avatarSuzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: default avatarMathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 68c0dacb
......@@ -3,6 +3,7 @@
* 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>
......@@ -308,10 +309,471 @@ of_get_coresight_platform_data(struct device *dev,
}
#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);
......@@ -334,6 +796,8 @@ coresight_get_platform_data(struct device *dev)
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;
......
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