[PATCH v5 2/8] drm/xe: Add xe_gt_clock_interval_to_ns function

[Aakash Deep Sarkar <aakash.deep.sarkar@intel.com>]

The runtime of a user id in the GPU work period event are required
to be given in nanosec unit. Since we want to use the HW Context
timestamp register to derive the runtime for a context, we need
a way to convert from GT clock ticks to nano seconds.

Signed-off-by: Aakash Deep Sarkar <aakash.deep.sarkar@intel.com>
---
 drivers/gpu/drm/xe/xe_gt_clock.c | 14 ++++++++++++++
 drivers/gpu/drm/xe/xe_gt_clock.h |  1 +
 2 files changed, 15 insertions(+)

diff --git a/drivers/gpu/drm/xe/xe_gt_clock.c b/drivers/gpu/drm/xe/xe_gt_clock.c
index 4f011d1573c6..17c1cc6bff5a 100644
--- a/drivers/gpu/drm/xe/xe_gt_clock.c
+++ b/drivers/gpu/drm/xe/xe_gt_clock.c
@@ -110,3 +110,17 @@ u64 xe_gt_clock_interval_to_ms(struct xe_gt *gt, u64 count)
 {
 	return div_u64_roundup(count * MSEC_PER_SEC, gt->info.reference_clock);
 }
+
+/**
+ * xe_gt_clock_interval_to_ns - Convert sampled GT clock ticks to nanosec
+ *
+ * @gt: the &xe_gt
+ * @count: count of GT clock ticks
+ *
+ * Returns: time in nanosec
+ */
+u64 xe_gt_clock_interval_to_ns(struct xe_gt *gt, u64 count)
+{
+	return div_u64_roundup(count * NSEC_PER_SEC, gt->info.reference_clock);
+}
+
diff --git a/drivers/gpu/drm/xe/xe_gt_clock.h b/drivers/gpu/drm/xe/xe_gt_clock.h
index 3adeb7baaca4..bd87971bce97 100644
--- a/drivers/gpu/drm/xe/xe_gt_clock.h
+++ b/drivers/gpu/drm/xe/xe_gt_clock.h
@@ -12,5 +12,6 @@ struct xe_gt;
 
 int xe_gt_clock_init(struct xe_gt *gt);
 u64 xe_gt_clock_interval_to_ms(struct xe_gt *gt, u64 count);
+u64 xe_gt_clock_interval_to_ns(struct xe_gt *gt, u64 count);
 
 #endif
-- 
2.49.0