[PATCH 6/7] drm/xe/guc: Expose engine busyness only for supported GuC version

[Umesh Nerlige Ramappa]

On Wed, Nov 13, 2024 at 10:25:48AM +0530, Riana Tauro wrote:
>Engine busyness is supported only on GuC versions >= 70.32.0
>Allow enabling/reading engine busyness only on supported
>GuC versions. Warn once if not supported.
>
>Signed-off-by: Riana Tauro <riana.tauro at intel.com>
>---
> drivers/gpu/drm/xe/xe_engine_activity.c | 22 ++++++++++++++++++++++
> 1 file changed, 22 insertions(+)
>
>diff --git a/drivers/gpu/drm/xe/xe_engine_activity.c b/drivers/gpu/drm/xe/xe_engine_activity.c
>index 7a2ae09d23de..fc34dcf3057a 100644
>--- a/drivers/gpu/drm/xe/xe_engine_activity.c
>+++ b/drivers/gpu/drm/xe/xe_engine_activity.c
>@@ -236,6 +236,16 @@ static u32 gpm_timestamp_shift(struct xe_gt *gt)
> 	return 3 - REG_FIELD_GET(RPM_CONFIG0_CTC_SHIFT_PARAMETER_MASK, reg);
> }
>
>+static bool guc_engine_activity_supported(struct xe_guc *guc)
>+{
>+	if (GUC_FIRMWARE_VER(guc) >= MAKE_GUC_VER(70, 32, 0))
>+		return true;
>+
>+	drm_WARN_ON_ONCE(&guc_to_xe(guc)->drm,
>+			 "Engine busyness not supported in this GuC version\n");
>+	return false;
>+}
>+
> /**
>  * xe_engine_activity_get_active_ticks - Get engine active ticks
>  * @hwe: The hw_engine object
>@@ -246,6 +256,9 @@ u64 xe_engine_activity_get_active_ticks(struct xe_hw_engine *hwe)
> {
> 	struct xe_guc *guc =  &hwe->gt->uc.guc;
>
>+	if (!guc_engine_activity_supported(guc))
>+		return 0;
>+
> 	return get_engine_active_ticks(guc, hwe);
> }
>
>@@ -259,6 +272,9 @@ u64 xe_engine_activity_get_total_ticks(struct xe_hw_engine *hwe)
> {
> 	struct xe_guc *guc =  &hwe->gt->uc.guc;
>
>+	if (!guc_engine_activity_supported(guc))

Hmm, not sure my response to this landed on the ML. Sending again..

If GuC is an older version and UMDs have implemented the new interface, 
we could return CPU time in ticks here so that UMDs will still be able 
to use something in the denominator instead of a divide by zero. Busy 
value will still be 0. Thoughts?

Umesh

>+		return 0;
>+
> 	return get_engine_total_ticks(guc, hwe);
> }