[PATCH v3 3/6] powerpc/powernv: Detect supported IMC units and its events

[Hemant Kumar]

Parse device tree to detect IMC units. Traverse through each IMC unit
node to find supported events and corresponding unit/scale files (if any).

Right now, only nest IMC units are supported.
The nest IMC unit event node from device tree will contain the offset in
the reserved memory region to get the counter data for a given
event. The offsets for the nest events are contained in the "reg"
property of the event "node".

Kernel code uses this offset as event configuration value.

Device tree parser code also looks for scale/unit property in the event
node and passes on the value as an event attr for perf interface to use
in the post processing by the perf tool. Some PMUs may have common scale
and unit properties which implies that all events supported by this PMU
inherit the scale and unit properties of the PMU itself. For those
events, we need to set the common unit and scale values.

For failure to initialize any unit or any event, disable that unit and
continue setting up the rest of them.

Cc: Madhavan Srinivasan 
Cc: Michael Ellerman 
Cc: Benjamin Herrenschmidt 
Cc: Paul Mackerras 
Cc: Anton Blanchard 
Cc: Sukadev Bhattiprolu 
Cc: Michael Neuling 
Cc: Stewart Smith 
Cc: Daniel Axtens 
Cc: Stephane Eranian 
Signed-off-by: Hemant Kumar 
---
 arch/powerpc/platforms/powernv/opal-imc.c | 332 ++
 1 file changed, 332 insertions(+)

diff --git a/arch/powerpc/platforms/powernv/opal-imc.c 
b/arch/powerpc/platforms/powernv/opal-imc.c
index ee2ae45..5ee93402 100644
--- a/arch/powerpc/platforms/powernv/opal-imc.c
+++ b/arch/powerpc/platforms/powernv/opal-imc.c
@@ -32,6 +32,337 @@
 #include 
 
 struct perchip_nest_info nest_perchip_info[IMC_MAX_CHIPS];
+struct imc_pmu *per_nest_pmu_arr[IMC_MAX_PMUS];
+
+static int imc_event_info(char *name, struct imc_events *events)
+{
+   char *buf;
+
+   /* memory for content */
+   buf = kzalloc(IMC_MAX_PMU_NAME_LEN, GFP_KERNEL);
+   if (!buf)
+   return -ENOMEM;
+
+   events->ev_name = name;
+   events->ev_value = buf;
+   return 0;
+}
+
+static int imc_event_info_str(struct property *pp, char *name,
+  struct imc_events *events)
+{
+   int ret;
+
+   ret = imc_event_info(name, events);
+   if (ret)
+   return ret;
+
+   if (!pp->value || (strnlen(pp->value, pp->length) == pp->length) ||
+  (pp->length > IMC_MAX_PMU_NAME_LEN))
+   return -EINVAL;
+   strncpy(events->ev_value, (const char *)pp->value, pp->length);
+
+   return 0;
+}
+
+static int imc_event_info_val(char *name, u32 val,
+ struct imc_events *events)
+{
+   int ret;
+
+   ret = imc_event_info(name, events);
+   if (ret)
+   return ret;
+   sprintf(events->ev_value, "event=0x%x", val);
+
+   return 0;
+}
+
+static int set_event_property(struct property *pp, char *event_prop,
+ struct imc_events *events, char *ev_name)
+{
+   char *buf;
+   int ret;
+
+   buf = kzalloc(IMC_MAX_PMU_NAME_LEN, GFP_KERNEL);
+   if (!buf)
+   return -ENOMEM;
+
+   sprintf(buf, "%s.%s", ev_name, event_prop);
+   ret = imc_event_info_str(pp, buf, events);
+   if (ret) {
+   kfree(events->ev_name);
+   kfree(events->ev_value);
+   }
+
+   return ret;
+}
+
+/*
+ * imc_events_node_parser: Parse the event node "dev" and assign the parsed
+ * information to event "events".
+ *
+ * Parses the "reg" property of this event. "reg" gives us the event offset.
+ * Also, parse the "scale" and "unit" properties, if any.
+ */
+static int imc_events_node_parser(struct device_node *dev,
+ struct imc_events *events,
+ struct property *event_scale,
+ struct property *event_unit)
+{
+   struct property *name, *pp;
+   char *ev_name;
+   u32 val;
+   int idx = 0, ret;
+
+   if (!dev)
+   return -EINVAL;
+
+   /*
+* Loop through each property of an event node
+*/
+   name = of_find_property(dev, "event-name", NULL);
+   if (!name)
+   return -ENODEV;
+
+   if (!name->value ||
+ (strnlen(name->value, name->length) == name->length) ||
+ (name->length > IMC_MAX_PMU_NAME_LEN))
+   return -EINVAL;
+
+   ev_name = kzalloc(IMC_MAX_PMU_NAME_LEN, GFP_KERNEL);
+   if (!ev_name)
+   return -ENOMEM;
+
+   strncpy(ev_name, name->value, name->length);
+
+   /*
+* Parse each property of this event node "dev". Property "reg" has
+* the offset which is assigned to 

[PATCH v3 3/6] powerpc/powernv: Detect supported IMC units and its events

[Hemant Kumar]

Parse device tree to detect IMC units. Traverse through each IMC unit
node to find supported events and corresponding unit/scale files (if any).

Right now, only nest IMC units are supported.
The nest IMC unit event node from device tree will contain the offset in
the reserved memory region to get the counter data for a given
event. The offsets for the nest events are contained in the "reg"
property of the event "node".

Kernel code uses this offset as event configuration value.

Device tree parser code also looks for scale/unit property in the event
node and passes on the value as an event attr for perf interface to use
in the post processing by the perf tool. Some PMUs may have common scale
and unit properties which implies that all events supported by this PMU
inherit the scale and unit properties of the PMU itself. For those
events, we need to set the common unit and scale values.

For failure to initialize any unit or any event, disable that unit and
continue setting up the rest of them.

Cc: Madhavan Srinivasan 
Cc: Michael Ellerman 
Cc: Benjamin Herrenschmidt 
Cc: Paul Mackerras 
Cc: Anton Blanchard 
Cc: Sukadev Bhattiprolu 
Cc: Michael Neuling 
Cc: Stewart Smith 
Cc: Daniel Axtens 
Cc: Stephane Eranian 
Signed-off-by: Hemant Kumar 
---
 arch/powerpc/platforms/powernv/opal-imc.c | 332 ++
 1 file changed, 332 insertions(+)

diff --git a/arch/powerpc/platforms/powernv/opal-imc.c 
b/arch/powerpc/platforms/powernv/opal-imc.c
index ee2ae45..5ee93402 100644
--- a/arch/powerpc/platforms/powernv/opal-imc.c
+++ b/arch/powerpc/platforms/powernv/opal-imc.c
@@ -32,6 +32,337 @@
 #include 
 
 struct perchip_nest_info nest_perchip_info[IMC_MAX_CHIPS];
+struct imc_pmu *per_nest_pmu_arr[IMC_MAX_PMUS];
+
+static int imc_event_info(char *name, struct imc_events *events)
+{
+   char *buf;
+
+   /* memory for content */
+   buf = kzalloc(IMC_MAX_PMU_NAME_LEN, GFP_KERNEL);
+   if (!buf)
+   return -ENOMEM;
+
+   events->ev_name = name;
+   events->ev_value = buf;
+   return 0;
+}
+
+static int imc_event_info_str(struct property *pp, char *name,
+  struct imc_events *events)
+{
+   int ret;
+
+   ret = imc_event_info(name, events);
+   if (ret)
+   return ret;
+
+   if (!pp->value || (strnlen(pp->value, pp->length) == pp->length) ||
+  (pp->length > IMC_MAX_PMU_NAME_LEN))
+   return -EINVAL;
+   strncpy(events->ev_value, (const char *)pp->value, pp->length);
+
+   return 0;
+}
+
+static int imc_event_info_val(char *name, u32 val,
+ struct imc_events *events)
+{
+   int ret;
+
+   ret = imc_event_info(name, events);
+   if (ret)
+   return ret;
+   sprintf(events->ev_value, "event=0x%x", val);
+
+   return 0;
+}
+
+static int set_event_property(struct property *pp, char *event_prop,
+ struct imc_events *events, char *ev_name)
+{
+   char *buf;
+   int ret;
+
+   buf = kzalloc(IMC_MAX_PMU_NAME_LEN, GFP_KERNEL);
+   if (!buf)
+   return -ENOMEM;
+
+   sprintf(buf, "%s.%s", ev_name, event_prop);
+   ret = imc_event_info_str(pp, buf, events);
+   if (ret) {
+   kfree(events->ev_name);
+   kfree(events->ev_value);
+   }
+
+   return ret;
+}
+
+/*
+ * imc_events_node_parser: Parse the event node "dev" and assign the parsed
+ * information to event "events".
+ *
+ * Parses the "reg" property of this event. "reg" gives us the event offset.
+ * Also, parse the "scale" and "unit" properties, if any.
+ */
+static int imc_events_node_parser(struct device_node *dev,
+ struct imc_events *events,
+ struct property *event_scale,
+ struct property *event_unit)
+{
+   struct property *name, *pp;
+   char *ev_name;
+   u32 val;
+   int idx = 0, ret;
+
+   if (!dev)
+   return -EINVAL;
+
+   /*
+* Loop through each property of an event node
+*/
+   name = of_find_property(dev, "event-name", NULL);
+   if (!name)
+   return -ENODEV;
+
+   if (!name->value ||
+ (strnlen(name->value, name->length) == name->length) ||
+ (name->length > IMC_MAX_PMU_NAME_LEN))
+   return -EINVAL;
+
+   ev_name = kzalloc(IMC_MAX_PMU_NAME_LEN, GFP_KERNEL);
+   if (!ev_name)
+   return -ENOMEM;
+
+   strncpy(ev_name, name->value, name->length);
+
+   /*
+* Parse each property of this event node "dev". Property "reg" has
+* the offset which is assigned to the event name. Other properties
+* like "scale" and "unit" are assigned to event.scale and event.unit
+* accordingly.
+*/
+   for_each_property_of_node(dev, pp) {
+   /*
+* If there is an