Parse device tree to detect supported nest pmu units. Traverse
through each nest pmu unit folder to find supported events and
corresponding unit/scale files (if any).
The nest unit event file from Device Tree will contain the offset in the
reserved memory region to get the counter data for a given event.
Kernel code uses this offset as event configuration value.
Device tree parser code also looks for scale/unit in the file name and
passes on the file as an event attr for perf tool to use in the post
processing.
Cc: Michael Ellerman <m...@ellerman.id.au>
Cc: Benjamin Herrenschmidt <b...@kernel.crashing.org>
Cc: Paul Mackerras <pau...@samba.org>
Cc: Anton Blanchard <an...@samba.org>
Cc: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
Cc: Daniel Axtens <d...@axtens.net>
Cc: Stephane Eranian <eran...@google.com>
Signed-off-by: Madhavan Srinivasan <ma...@linux.vnet.ibm.com>
---
arch/powerpc/perf/nest-pmu.c | 137 +++++++++++++++++++++++++++++++++++++++++++
1 file changed, 137 insertions(+)
diff --git a/arch/powerpc/perf/nest-pmu.c b/arch/powerpc/perf/nest-pmu.c
index 48738f9f6426..292fc2b91ed0 100644
--- a/arch/powerpc/perf/nest-pmu.c
+++ b/arch/powerpc/perf/nest-pmu.c
@@ -11,12 +11,140 @@
#include "nest-pmu.h"
static struct perchip_nest_info p8_nest_perchip_info[P8_NEST_MAX_CHIPS];
+static struct nest_pmu *per_nest_pmu_arr[P8_NEST_MAX_PMUS];
+
+static int nest_event_info(char *name, struct nest_ima_events *p8_events)
+{
+ char *buf;
+
+ /* memory for event name */
+ buf = kzalloc(P8_NEST_MAX_PMU_NAME_LEN, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ strncpy(buf, name, strlen(name));
+ p8_events->ev_name = buf;
+
+ /* memory for content */
+ buf = kzalloc(P8_NEST_MAX_PMU_NAME_LEN, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ p8_events->ev_value = buf;
+ return 0;
+}
+
+static int nest_event_info_str(struct property *pp, char *name,
+ struct nest_ima_events *p8_events)
+{
+ if (nest_event_info(name, p8_events))
+ return -ENOMEM;
+
+ if (!pp->value || (strnlen(pp->value, pp->length) == pp->length) ||
+ (pp->length > P8_NEST_MAX_PMU_NAME_LEN))
+ return -EINVAL;
+
+ strncpy(p8_events->ev_value, (const char *)pp->value, pp->length);
+
+ return 0;
+}
+
+static int nest_event_info_val(char *name, u32 val,
+ struct nest_ima_events *p8_events)
+{
+ if (nest_event_info(name, p8_events))
+ return -ENOMEM;
+
+ sprintf(p8_events->ev_value, "event=0x%x", val);
+
+ return 0;
+}
+
+static int nest_pmu_create(struct device_node *dev, int pmu_index)
+{
+ struct nest_ima_events *p8_events;
+ struct nest_pmu *pmu_ptr;
+ struct property *pp;
+ char *buf, *start;
+ u32 val;
+ int idx = 0, ret;
+
+ if (!dev)
+ return -EINVAL;
+
+ /* memory for nest pmus */
+ pmu_ptr = kzalloc(sizeof(struct nest_pmu), GFP_KERNEL);
+ if (!pmu_ptr)
+ return -ENOMEM;
+
+ /* Needed for hotplug/migration */
+ per_nest_pmu_arr[pmu_index] = pmu_ptr;
+
+ /* memory for nest pmu events */
+ p8_events = kzalloc((sizeof(struct nest_ima_events) *
+ P8_NEST_MAX_EVENTS_SUPPORTED), GFP_KERNEL);
+ if (!p8_events)
+ return -ENOMEM;
+
+ /*
+ * Loop through each property
+ */
+ for_each_property_of_node(dev, pp) {
+ start = pp->name;
+
+ if (!strcmp(pp->name, "name")) {
+ if (!pp->value ||
+ (strnlen(pp->value, pp->length) == pp->length) ||
+ (pp->length > P8_NEST_MAX_PMU_NAME_LEN))
+ return -EINVAL;
+
+ buf = kzalloc(P8_NEST_MAX_PMU_NAME_LEN, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ /* Save the name to register it later */
+ sprintf(buf, "Nest_%s", (char *)pp->value);
+ pmu_ptr->pmu.name = (char *)buf;
+ continue;
+ }
+
+ /* Skip these, we don't need it */
+ if (!strcmp(pp->name, "phandle") ||
+ !strcmp(pp->name, "device_type") ||
+ !strcmp(pp->name, "linux,phandle"))
+ continue;
+
+ /*
+ * Strip the prefix from "unit" and "scale" property name
+ * since it is only a marker search
+ */
+ if (strncmp(pp->name, "unit.", 5) == 0) {
+ start += 5;
+ ret = nest_event_info_str(pp, start, &p8_events[idx]);
+ } else if (strncmp(pp->name, "scale.", 6) == 0) {
+ start += 6;
+ ret = nest_event_info_str(pp, start, &p8_events[idx]);
+ } else {
+ of_property_read_u32(dev, pp->name, &val);
+ ret = nest_event_info_val(start, val, &p8_events[idx]);
+ }
+
+ if (ret)
+ return ret;
+
+ /* book keeping */
+ idx++;
+ }
+
+ return 0;
+}
static int nest_ima_dt_parser(void)
{
struct device_node *dev;
struct perchip_nest_info *p8ni;
u32 idx;
+ int ret;
/*
* "nest-ima" folder contains two things,
@@ -39,6 +167,15 @@ static int nest_ima_dt_parser(void)
p8ni->vbase = (u64)phys_to_virt(p8ni->pbase);
}
+ /* Look for supported Nest PMU units */
+ idx = 0;
+ for_each_node_by_type(dev, "nest-ima-unit") {
+ ret = nest_pmu_create(dev, idx);
+ if (ret)
+ return ret;
+ idx++;
+ }
+
return 0;
}
--
1.9.1
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