[PATCH v3 5/6] powerpc/perf: Generic imc pmu event functions

[Hemant Kumar]

Since, the IMC counters' data are periodically fed to a memory location,
the functions to read/update, start/stop, add/del can be generic and can
be used by all IMC PMU units.

This patch adds a set of generic imc pmu related event functions to be
used  by each imc pmu unit. Add code to setup format attribute and to
register imc pmus. Add a event_init function for nest_imc events.

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/include/asm/imc-pmu.h|   1 +
 arch/powerpc/perf/imc-pmu.c   | 122 ++
 arch/powerpc/platforms/powernv/opal-imc.c |  29 ++-
 3 files changed, 148 insertions(+), 4 deletions(-)

diff --git a/arch/powerpc/include/asm/imc-pmu.h 
b/arch/powerpc/include/asm/imc-pmu.h
index 911d837..ceb6b1f 100644
--- a/arch/powerpc/include/asm/imc-pmu.h
+++ b/arch/powerpc/include/asm/imc-pmu.h
@@ -70,4 +70,5 @@ struct imc_pmu {
 
 #define UNKNOWN_DOMAIN -1
 
+int imc_get_domain(struct device_node *pmu_dev);
 #endif /* PPC_POWERNV_IMC_PMU_DEF_H */
diff --git a/arch/powerpc/perf/imc-pmu.c b/arch/powerpc/perf/imc-pmu.c
index 7b6ce50..f12ece8 100644
--- a/arch/powerpc/perf/imc-pmu.c
+++ b/arch/powerpc/perf/imc-pmu.c
@@ -17,6 +17,117 @@
 struct perchip_nest_info nest_perchip_info[IMC_MAX_CHIPS];
 struct imc_pmu *per_nest_pmu_arr[IMC_MAX_PMUS];
 
+/* Needed for sanity check */
+extern u64 nest_max_offset;
+
+PMU_FORMAT_ATTR(event, "config:0-20");
+static struct attribute *imc_format_attrs[] = {
+   _attr_event.attr,
+   NULL,
+};
+
+static struct attribute_group imc_format_group = {
+   .name = "format",
+   .attrs = imc_format_attrs,
+};
+
+static int nest_imc_event_init(struct perf_event *event)
+{
+   int chip_id;
+   u32 config = event->attr.config;
+   struct perchip_nest_info *pcni;
+
+   if (event->attr.type != event->pmu->type)
+   return -ENOENT;
+
+   /* Sampling not supported */
+   if (event->hw.sample_period)
+   return -EINVAL;
+
+   /* unsupported modes and filters */
+   if (event->attr.exclude_user   ||
+   event->attr.exclude_kernel ||
+   event->attr.exclude_hv ||
+   event->attr.exclude_idle   ||
+   event->attr.exclude_host   ||
+   event->attr.exclude_guest)
+   return -EINVAL;
+
+   if (event->cpu < 0)
+   return -EINVAL;
+
+   /* Sanity check for config (event offset) */
+   if (config > nest_max_offset)
+   return -EINVAL;
+
+   chip_id = topology_physical_package_id(event->cpu);
+   pcni = _perchip_info[chip_id];
+   event->hw.event_base = pcni->vbase[config/PAGE_SIZE] +
+   (config & ~PAGE_MASK);
+
+   return 0;
+}
+
+static void imc_read_counter(struct perf_event *event)
+{
+   u64 *addr, data;
+
+   addr = (u64 *)event->hw.event_base;
+   data = __be64_to_cpu(*addr);
+   local64_set(>hw.prev_count, data);
+}
+
+static void imc_perf_event_update(struct perf_event *event)
+{
+   u64 counter_prev, counter_new, final_count, *addr;
+
+   addr = (u64 *)event->hw.event_base;
+   counter_prev = local64_read(>hw.prev_count);
+   counter_new = __be64_to_cpu(*addr);
+   final_count = counter_new - counter_prev;
+
+   local64_set(>hw.prev_count, counter_new);
+   local64_add(final_count, >count);
+}
+
+static void imc_event_start(struct perf_event *event, int flags)
+{
+   imc_read_counter(event);
+}
+
+static void imc_event_stop(struct perf_event *event, int flags)
+{
+   if (flags & PERF_EF_UPDATE)
+   imc_perf_event_update(event);
+}
+
+static int imc_event_add(struct perf_event *event, int flags)
+{
+   if (flags & PERF_EF_START)
+   imc_event_start(event, flags);
+
+   return 0;
+}
+
+/* update_pmu_ops : Populate the appropriate operations for "pmu" */
+static int update_pmu_ops(struct imc_pmu *pmu)
+{
+   if (!pmu)
+   return -EINVAL;
+
+   pmu->pmu.task_ctx_nr = perf_invalid_context;
+   pmu->pmu.event_init = nest_imc_event_init;
+   pmu->pmu.add = imc_event_add;
+   pmu->pmu.del = imc_event_stop;
+   pmu->pmu.start = imc_event_start;
+   pmu->pmu.stop = imc_event_stop;
+   pmu->pmu.read = imc_perf_event_update;
+   pmu->attr_groups[1] = _format_group;
+   pmu->pmu.attr_groups = pmu->attr_groups;
+
+   return 0;
+}
+
 /* dev_str_attr : Populate event "name" and string "str" in attribute */
 static struct 

[PATCH v3 5/6] powerpc/perf: Generic imc pmu event functions

[Hemant Kumar]

Since, the IMC counters' data are periodically fed to a memory location,
the functions to read/update, start/stop, add/del can be generic and can
be used by all IMC PMU units.

This patch adds a set of generic imc pmu related event functions to be
used  by each imc pmu unit. Add code to setup format attribute and to
register imc pmus. Add a event_init function for nest_imc events.

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/include/asm/imc-pmu.h|   1 +
 arch/powerpc/perf/imc-pmu.c   | 122 ++
 arch/powerpc/platforms/powernv/opal-imc.c |  29 ++-
 3 files changed, 148 insertions(+), 4 deletions(-)

diff --git a/arch/powerpc/include/asm/imc-pmu.h 
b/arch/powerpc/include/asm/imc-pmu.h
index 911d837..ceb6b1f 100644
--- a/arch/powerpc/include/asm/imc-pmu.h
+++ b/arch/powerpc/include/asm/imc-pmu.h
@@ -70,4 +70,5 @@ struct imc_pmu {
 
 #define UNKNOWN_DOMAIN -1
 
+int imc_get_domain(struct device_node *pmu_dev);
 #endif /* PPC_POWERNV_IMC_PMU_DEF_H */
diff --git a/arch/powerpc/perf/imc-pmu.c b/arch/powerpc/perf/imc-pmu.c
index 7b6ce50..f12ece8 100644
--- a/arch/powerpc/perf/imc-pmu.c
+++ b/arch/powerpc/perf/imc-pmu.c
@@ -17,6 +17,117 @@
 struct perchip_nest_info nest_perchip_info[IMC_MAX_CHIPS];
 struct imc_pmu *per_nest_pmu_arr[IMC_MAX_PMUS];
 
+/* Needed for sanity check */
+extern u64 nest_max_offset;
+
+PMU_FORMAT_ATTR(event, "config:0-20");
+static struct attribute *imc_format_attrs[] = {
+   _attr_event.attr,
+   NULL,
+};
+
+static struct attribute_group imc_format_group = {
+   .name = "format",
+   .attrs = imc_format_attrs,
+};
+
+static int nest_imc_event_init(struct perf_event *event)
+{
+   int chip_id;
+   u32 config = event->attr.config;
+   struct perchip_nest_info *pcni;
+
+   if (event->attr.type != event->pmu->type)
+   return -ENOENT;
+
+   /* Sampling not supported */
+   if (event->hw.sample_period)
+   return -EINVAL;
+
+   /* unsupported modes and filters */
+   if (event->attr.exclude_user   ||
+   event->attr.exclude_kernel ||
+   event->attr.exclude_hv ||
+   event->attr.exclude_idle   ||
+   event->attr.exclude_host   ||
+   event->attr.exclude_guest)
+   return -EINVAL;
+
+   if (event->cpu < 0)
+   return -EINVAL;
+
+   /* Sanity check for config (event offset) */
+   if (config > nest_max_offset)
+   return -EINVAL;
+
+   chip_id = topology_physical_package_id(event->cpu);
+   pcni = _perchip_info[chip_id];
+   event->hw.event_base = pcni->vbase[config/PAGE_SIZE] +
+   (config & ~PAGE_MASK);
+
+   return 0;
+}
+
+static void imc_read_counter(struct perf_event *event)
+{
+   u64 *addr, data;
+
+   addr = (u64 *)event->hw.event_base;
+   data = __be64_to_cpu(*addr);
+   local64_set(>hw.prev_count, data);
+}
+
+static void imc_perf_event_update(struct perf_event *event)
+{
+   u64 counter_prev, counter_new, final_count, *addr;
+
+   addr = (u64 *)event->hw.event_base;
+   counter_prev = local64_read(>hw.prev_count);
+   counter_new = __be64_to_cpu(*addr);
+   final_count = counter_new - counter_prev;
+
+   local64_set(>hw.prev_count, counter_new);
+   local64_add(final_count, >count);
+}
+
+static void imc_event_start(struct perf_event *event, int flags)
+{
+   imc_read_counter(event);
+}
+
+static void imc_event_stop(struct perf_event *event, int flags)
+{
+   if (flags & PERF_EF_UPDATE)
+   imc_perf_event_update(event);
+}
+
+static int imc_event_add(struct perf_event *event, int flags)
+{
+   if (flags & PERF_EF_START)
+   imc_event_start(event, flags);
+
+   return 0;
+}
+
+/* update_pmu_ops : Populate the appropriate operations for "pmu" */
+static int update_pmu_ops(struct imc_pmu *pmu)
+{
+   if (!pmu)
+   return -EINVAL;
+
+   pmu->pmu.task_ctx_nr = perf_invalid_context;
+   pmu->pmu.event_init = nest_imc_event_init;
+   pmu->pmu.add = imc_event_add;
+   pmu->pmu.del = imc_event_stop;
+   pmu->pmu.start = imc_event_start;
+   pmu->pmu.stop = imc_event_stop;
+   pmu->pmu.read = imc_perf_event_update;
+   pmu->attr_groups[1] = _format_group;
+   pmu->pmu.attr_groups = pmu->attr_groups;
+
+   return 0;
+}
+
 /* dev_str_attr : Populate event "name" and string "str" in attribute */
 static struct attribute *dev_str_attr(const char *name, const char *str)
 {
@@ -83,6 +194,17 @@ int init_imc_pmu(struct imc_events *events, int idx,
if (ret)
goto err_free;
 
+   ret = update_pmu_ops(pmu_ptr);
+   if (ret)
+