drm/i915: advertise available metrics via sysfs

Each metric set is given a sysfs entry like:

/sys/class/drm/card0/metrics/<guid>/id

This allows userspace to enumerate the specific sets that are available
for the current system. The 'id' file contains an unsigned integer that
can be used to open the associated metric set via
DRM_IOCTL_I915_PERF_OPEN. The <guid> is a globally unique ID for a
specific OA unit register configuration that can be reliably used by
userspace as a key to lookup corresponding counter meta data and
normalization equations.

The guid registry is currently maintained as part of gputop along with
the XML metric set descriptions and code generation scripts, ref:

 https://github.com/rib/gputop
 > gputop-data/guids.xml
 > scripts/update-guids.py
 > gputop-data/oa-*.xml
 > scripts/i915-perf-kernelgen.py

 $ make -C gputop-data -f Makefile.xml SYSFS=1 WHITELIST=RenderBasic

Signed-off-by: Robert Bragg <robert@sixbynine.org>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Sourab Gupta <sourab.gupta@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161107194957.3385-8-robert@sixbynine.org

1 files changed, 51 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/i915_oa_hsw.c b/drivers/gpu/drm/i915/i915_oa_hsw.c
index 8906380d9177..6af25cfefc22 100644
--- a/drivers/gpu/drm/i915/i915_oa_hsw.c
+++ b/drivers/gpu/drm/i915/i915_oa_hsw.c
@@ -24,6 +24,8 @@
  *
  */
 
+#include <linux/sysfs.h>
+
 #include "i915_drv.h"
 #include "i915_oa_hsw.h"
 
@@ -142,3 +144,52 @@ int i915_oa_select_metric_set_hsw(struct drm_i915_private *dev_priv)
 		return -ENODEV;
 	}
 }
+
+static ssize_t
+show_render_basic_id(struct device *kdev, struct device_attribute *attr, char *buf)
+{
+	return sprintf(buf, "%d\n", METRIC_SET_ID_RENDER_BASIC);
+}
+
+static struct device_attribute dev_attr_render_basic_id = {
+	.attr = { .name = "id", .mode = 0444 },
+	.show = show_render_basic_id,
+	.store = NULL,
+};
+
+static struct attribute *attrs_render_basic[] = {
+	&dev_attr_render_basic_id.attr,
+	NULL,
+};
+
+static struct attribute_group group_render_basic = {
+	.name = "403d8832-1a27-4aa6-a64e-f5389ce7b212",
+	.attrs =  attrs_render_basic,
+};
+
+int
+i915_perf_register_sysfs_hsw(struct drm_i915_private *dev_priv)
+{
+	int mux_len;
+	int ret = 0;
+
+	if (get_render_basic_mux_config(dev_priv, &mux_len)) {
+		ret = sysfs_create_group(dev_priv->perf.metrics_kobj, &group_render_basic);
+		if (ret)
+			goto error_render_basic;
+	}
+
+	return 0;
+
+error_render_basic:
+	return ret;
+}
+
+void
+i915_perf_unregister_sysfs_hsw(struct drm_i915_private *dev_priv)
+{
+	int mux_len;
+
+	if (get_render_basic_mux_config(dev_priv, &mux_len))
+		sysfs_remove_group(dev_priv->perf.metrics_kobj, &group_render_basic);
+}