[Intel-gfx] [PATCH 05/14] drm/i915/perf: expose sseu configuration to userspace on perf fd

[Lionel Landwerlin]

Enables userspace to determine the number of slices & subslices
enabled and also know what specific slices & subslices are enabled.
This information is required, for example, to be able to analyse some
OA counter reports where the counter configuration depends on the HW
slice configuration.

Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin at intel.com>
---
 drivers/gpu/drm/i915/i915_drv.h  | 12 ++++++++++++
 drivers/gpu/drm/i915/i915_perf.c | 14 ++++++++++++++
 include/uapi/drm/i915_drm.h      | 15 +++++++++++++++
 3 files changed, 41 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 10ffbfec3b2e..18e12e61949b 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -2966,6 +2966,18 @@ extern long i915_compat_ioctl(struct file *filp, unsigned int cmd,
 #endif
 extern const struct dev_pm_ops i915_pm_ops;
 
+static inline u64 i915_pack_sseu_to_user(struct sseu_dev_info *sseu)
+{
+	union drm_i915_gem_param_sseu user;
+
+	user.packed.slice_mask = sseu->slice_mask;
+	user.packed.subslice_mask = sseu->subslice_mask;
+	user.packed.min_eu_per_subslice = sseu->min_eu_per_subslice;
+	user.packed.max_eu_per_subslice = sseu->max_eu_per_subslice;
+
+	return user.value;
+}
+
 extern int i915_driver_load(struct pci_dev *pdev,
 			    const struct pci_device_id *ent);
 extern void i915_driver_unload(struct drm_device *dev);
diff --git a/drivers/gpu/drm/i915/i915_perf.c b/drivers/gpu/drm/i915/i915_perf.c
index 5f4eccaa06d6..d20cceef93d0 100644
--- a/drivers/gpu/drm/i915/i915_perf.c
+++ b/drivers/gpu/drm/i915/i915_perf.c
@@ -1618,6 +1618,18 @@ static void i915_perf_disable_locked(struct i915_perf_stream *stream)
 		stream->ops->disable(stream);
 }
 
+static int i915_perf_get_sseu_locked(struct i915_perf_stream *stream,
+				     unsigned long arg)
+{
+	struct drm_i915_private *dev_priv = stream->dev_priv;
+	u64 sseu = i915_pack_sseu_to_user(&dev_priv->perf.oa.sseu);
+
+	if (copy_to_user((void __user *)arg, &sseu, sizeof(sseu)) != 0)
+		return -EFAULT;
+
+	return 0;
+}
+
 /**
  * i915_perf_ioctl - support ioctl() usage with i915 perf stream FDs
  * @stream: An i915 perf stream
@@ -1641,6 +1653,8 @@ static long i915_perf_ioctl_locked(struct i915_perf_stream *stream,
 	case I915_PERF_IOCTL_DISABLE:
 		i915_perf_disable_locked(stream);
 		return 0;
+	case I915_PERF_IOCTL_GET_SSEU:
+		return i915_perf_get_sseu_locked(stream, arg);
 	}
 
 	return -EINVAL;
diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h
index ba722fb343a4..8871c526205b 100644
--- a/include/uapi/drm/i915_drm.h
+++ b/include/uapi/drm/i915_drm.h
@@ -350,6 +350,16 @@ typedef struct drm_i915_irq_wait {
 	int irq_seq;
 } drm_i915_irq_wait_t;
 
+union drm_i915_gem_param_sseu {
+	struct {
+		u8 slice_mask;
+		u8 subslice_mask;
+		u8 min_eu_per_subslice;
+		u8 max_eu_per_subslice;
+	} packed;
+	__u64 value;
+};
+
 /* Ioctl to query kernel params:
  */
 #define I915_PARAM_IRQ_ACTIVE            1
@@ -1399,6 +1409,11 @@ struct drm_i915_perf_open_param {
 #define I915_PERF_IOCTL_DISABLE	_IO('i', 0x1)
 
 /**
+ * Query sseu configuration for a stream.
+ */
+#define I915_PERF_IOCTL_GET_SSEU _IOW('i', 0x2, union drm_i915_gem_param_sseu)
+
+/**
  * Common to all i915 perf records
  */
 struct drm_i915_perf_record_header {
-- 
2.11.0