Dynamic trace id was introduced in coresight subsystem, so trace id is
allocated dynamically. However, some hardware ATB source has static trace
id and it cannot be changed via software programming. For such source,
it can call coresight_get_source_traceid to get the fixed trace id from
device node and pass id to coresight_trace_id_get_system_id to reserve
the id.
Signed-off-by: Mao Jinlong <quic_jinlmao@xxxxxxxxxxx>
---
.../hwtracing/coresight/coresight-platform.c | 25 +++++++++++++
drivers/hwtracing/coresight/coresight-stm.c | 2 +-
drivers/hwtracing/coresight/coresight-tpda.c | 2 +-
.../hwtracing/coresight/coresight-trace-id.c | 35 ++++++++++++-------
.../hwtracing/coresight/coresight-trace-id.h | 11 +++++-
include/linux/coresight.h | 1 +
6 files changed, 61 insertions(+), 15 deletions(-)
diff --git a/drivers/hwtracing/coresight/coresight-platform.c b/drivers/hwtracing/coresight/coresight-platform.c
index 9d550f5697fa..df169f3f367e 100644
--- a/drivers/hwtracing/coresight/coresight-platform.c
+++ b/drivers/hwtracing/coresight/coresight-platform.c
@@ -183,6 +183,17 @@ static int of_coresight_get_cpu(struct device *dev)
return cpu;
}
+/*
+ * of_coresight_get_trace_id: Get the atid of a source device.
+ *
+ * Returns 0 on success.
+ */
+static int of_coresight_get_trace_id(struct device *dev, u32 *id)
+{
+
+ return of_property_read_u32(dev->of_node, "arm,trace-id", id);
+}
+
/*
* of_coresight_parse_endpoint : Parse the given output endpoint @ep
* and fill the connection information in @pdata->out_conns
@@ -315,6 +326,11 @@ static inline int of_coresight_get_cpu(struct device *dev)
{
return -ENODEV;
}
+
+static inline int of_coresight_get_trace_id(struct device *dev, u32 *id)
+{
+ return -ENODEV;
+}
#endif
#ifdef CONFIG_ACPI
@@ -794,6 +810,15 @@ int coresight_get_cpu(struct device *dev)
}
EXPORT_SYMBOL_GPL(coresight_get_cpu);
+int coresight_get_source_traceid(struct device *dev, u32 *id)
+{
+ if (!is_of_node(dev->fwnode))
+ return -EINVAL;
+
+ return of_coresight_get_trace_id(dev, id);
+}
+EXPORT_SYMBOL_GPL(coresight_get_source_traceid);
+
struct coresight_platform_data *
coresight_get_platform_data(struct device *dev)
{
diff --git a/drivers/hwtracing/coresight/coresight-stm.c b/drivers/hwtracing/coresight/coresight-stm.c
index e1c62820dfda..34fab2ce9a76 100644
--- a/drivers/hwtracing/coresight/coresight-stm.c
+++ b/drivers/hwtracing/coresight/coresight-stm.c
@@ -901,7 +901,7 @@ static int __stm_probe(struct device *dev, struct resource *res)
goto stm_unregister;
}
- trace_id = coresight_trace_id_get_system_id();
+ trace_id = coresight_trace_id_get_system_id(TRACE_ID_ANY);
if (trace_id < 0) {
ret = trace_id;
goto cs_unregister;
diff --git a/drivers/hwtracing/coresight/coresight-tpda.c b/drivers/hwtracing/coresight/coresight-tpda.c
index 7739bc7adc44..46161cadb9e5 100644
--- a/drivers/hwtracing/coresight/coresight-tpda.c
+++ b/drivers/hwtracing/coresight/coresight-tpda.c
@@ -251,7 +251,7 @@ static int tpda_init_default_data(struct tpda_drvdata *drvdata)
* same trace-id. When TPDA does packetization, different
* port will have unique channel number for decoding.
*/
- atid = coresight_trace_id_get_system_id();
+ atid = coresight_trace_id_get_system_id(TRACE_ID_ANY);
if (atid < 0)
return atid;
diff --git a/drivers/hwtracing/coresight/coresight-trace-id.c b/drivers/hwtracing/coresight/coresight-trace-id.c
index af5b4ef59cea..59194f60362c 100644
--- a/drivers/hwtracing/coresight/coresight-trace-id.c
+++ b/drivers/hwtracing/coresight/coresight-trace-id.c
@@ -75,21 +75,26 @@ static int coresight_trace_id_find_odd_id(struct coresight_trace_id_map *id_map)
* Allocate new ID and set in use
*
* if @preferred_id is a valid id then try to use that value if available.
- * if @preferred_id is not valid and @prefer_odd_id is true, try for odd id.
+ * if TRACE_ID_WANT_PREFERRED is set, @preferred_id must be free, otherwise return
+ * error -EINVAL.
+ * if @preferred_id is not valid and TRACE_ID_WANT_ODD is true, try for odd id.
*
* Otherwise allocate next available ID.
*/
static int coresight_trace_id_alloc_new_id(struct coresight_trace_id_map *id_map,
- int preferred_id, bool prefer_odd_id)
+ int preferred_id, unsigned int flags)
{
int id = 0;
/* for backwards compatibility, cpu IDs may use preferred value */
- if (IS_VALID_CS_TRACE_ID(preferred_id) &&
- !test_bit(preferred_id, id_map->used_ids)) {
- id = preferred_id;
- goto trace_id_allocated;
- } else if (prefer_odd_id) {
+ if (IS_VALID_CS_TRACE_ID(preferred_id)) {
+ if (!test_bit(preferred_id, id_map->used_ids)) {
+ id = preferred_id;
+ goto trace_id_allocated;
+ } else if (WARN((flags & TRACE_ID_WANT_PREFERRED), "Trace ID %d is used.\n",
+ preferred_id))
+ return -EINVAL;
+ } else if (flags & TRACE_ID_WANT_ODD) {
/* may use odd ids to avoid preferred legacy cpu IDs */
id = coresight_trace_id_find_odd_id(id_map);
if (id)
@@ -175,7 +180,7 @@ static int coresight_trace_id_map_get_cpu_id(int cpu, struct coresight_trace_id_
*/
id = coresight_trace_id_alloc_new_id(id_map,
CORESIGHT_LEGACY_CPU_TRACE_ID(cpu),
- false);
+ TRACE_ID_ANY);
if (!IS_VALID_CS_TRACE_ID(id))
goto get_cpu_id_out_unlock;
@@ -222,14 +227,20 @@ static void coresight_trace_id_map_put_cpu_id(int cpu, struct coresight_trace_id
DUMP_ID_MAP(id_map);
}
-static int coresight_trace_id_map_get_system_id(struct coresight_trace_id_map *id_map)
+static int coresight_trace_id_map_get_system_id(struct coresight_trace_id_map *id_map,
+ int preferred_id)
{
unsigned long flags;
int id;
+ unsigned int traceid_flags = 0;
spin_lock_irqsave(&id_map_lock, flags);
+
/* prefer odd IDs for system components to avoid legacy CPU IDS */
- id = coresight_trace_id_alloc_new_id(id_map, 0, true);
+ traceid_flags = TRACE_ID_WANT_ODD;
+ traceid_flags |= preferred_id > 0 ? TRACE_ID_WANT_PREFERRED : 0;
+
+ id = coresight_trace_id_alloc_new_id(id_map, preferred_id, traceid_flags);
spin_unlock_irqrestore(&id_map_lock, flags);
DUMP_ID(id);
@@ -269,9 +280,9 @@ int coresight_trace_id_read_cpu_id(int cpu)
}
EXPORT_SYMBOL_GPL(coresight_trace_id_read_cpu_id);
-int coresight_trace_id_get_system_id(void)
+int coresight_trace_id_get_system_id(int id)
{
- return coresight_trace_id_map_get_system_id(&id_map_default);
+ return coresight_trace_id_map_get_system_id(&id_map_default, id);
}
EXPORT_SYMBOL_GPL(coresight_trace_id_get_system_id);
diff --git a/drivers/hwtracing/coresight/coresight-trace-id.h b/drivers/hwtracing/coresight/coresight-trace-id.h
index 3797777d367e..a236cf87c169 100644
--- a/drivers/hwtracing/coresight/coresight-trace-id.h
+++ b/drivers/hwtracing/coresight/coresight-trace-id.h
@@ -61,6 +61,12 @@ struct coresight_trace_id_map {
DECLARE_BITMAP(pend_rel_ids, CORESIGHT_TRACE_IDS_MAX);
};
+enum trace_id_flags {
+ TRACE_ID_ANY = 0x0,
+ TRACE_ID_WANT_ODD = 0x1,
+ TRACE_ID_WANT_PREFERRED = 0x2,
+};
+
/* Allocate and release IDs for a single default trace ID map */
/**
@@ -118,9 +124,12 @@ int coresight_trace_id_read_cpu_id(int cpu);
*
* Used to allocate IDs for system trace sources such as STM.
*
+ * @id: Preferred id value. If id is TRACE_ID_ANY, get a free id from id map.
+ * If id is greater than TRACE_ID_ANY, get a preferred id.
+ *
* return: Trace ID or -EINVAL if allocation is impossible.
*/
-int coresight_trace_id_get_system_id(void);
+int coresight_trace_id_get_system_id(int id);
/**
* Release an allocated system trace ID.
diff --git a/include/linux/coresight.h b/include/linux/coresight.h
index f09ace92176e..0599303be326 100644
--- a/include/linux/coresight.h
+++ b/include/linux/coresight.h
@@ -643,6 +643,7 @@ void coresight_relaxed_write64(struct coresight_device *csdev,
void coresight_write64(struct coresight_device *csdev, u64 val, u32 offset);
extern int coresight_get_cpu(struct device *dev);
+extern int coresight_get_source_traceid(struct device *dev, u32 *id);
struct coresight_platform_data *coresight_get_platform_data(struct device *dev);
struct coresight_connection *
--
2.41.0
