From: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@xxxxxxxxx>
Add a helper to capture CTX_TIMESTAMP from the context image so it can
be used to calculate the runtime.
v2: Add kernel-doc to clarify expectation from caller
Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@xxxxxxxxx>
Reviewed-by: Francois Dugast <francois.dugast@xxxxxxxxx>
Signed-off-by: Lucas De Marchi <lucas.demarchi@xxxxxxxxx>
---
drivers/gpu/drm/xe/regs/xe_lrc_layout.h | 1 +
drivers/gpu/drm/xe/xe_lrc.c | 12 ++++++++++++
drivers/gpu/drm/xe/xe_lrc.h | 14 ++++++++++++++
drivers/gpu/drm/xe/xe_lrc_types.h | 3 +++
4 files changed, 30 insertions(+)
diff --git a/drivers/gpu/drm/xe/regs/xe_lrc_layout.h b/drivers/gpu/drm/xe/regs/xe_lrc_layout.h
index e6ca8bbda8f4..045dfd09db99 100644
--- a/drivers/gpu/drm/xe/regs/xe_lrc_layout.h
+++ b/drivers/gpu/drm/xe/regs/xe_lrc_layout.h
@@ -11,6 +11,7 @@
#define CTX_RING_TAIL (0x06 + 1)
#define CTX_RING_START (0x08 + 1)
#define CTX_RING_CTL (0x0a + 1)
+#define CTX_TIMESTAMP (0x22 + 1)
#define CTX_INDIRECT_RING_STATE (0x26 + 1)
#define CTX_PDP0_UDW (0x30 + 1)
#define CTX_PDP0_LDW (0x32 + 1)
diff --git a/drivers/gpu/drm/xe/xe_lrc.c b/drivers/gpu/drm/xe/xe_lrc.c
index 9b0a4078add3..f679cb9aaea7 100644
--- a/drivers/gpu/drm/xe/xe_lrc.c
+++ b/drivers/gpu/drm/xe/xe_lrc.c
@@ -844,6 +844,7 @@ int xe_lrc_init(struct xe_lrc *lrc, struct xe_hw_engine *hwe,
lrc->tile = gt_to_tile(hwe->gt);
lrc->ring.size = ring_size;
lrc->ring.tail = 0;
+ lrc->ctx_timestamp = 0;
xe_hw_fence_ctx_init(&lrc->fence_ctx, hwe->gt,
hwe->fence_irq, hwe->name);
@@ -898,6 +899,8 @@ int xe_lrc_init(struct xe_lrc *lrc, struct xe_hw_engine *hwe,
RING_CTL_SIZE(lrc->ring.size) | RING_VALID);
}
+ xe_lrc_write_ctx_reg(lrc, CTX_TIMESTAMP, 0);
+
if (xe->info.has_asid && vm)
xe_lrc_write_ctx_reg(lrc, PVC_CTX_ASID, vm->usm.asid);
@@ -1576,3 +1579,12 @@ void xe_lrc_snapshot_free(struct xe_lrc_snapshot *snapshot)
xe_bo_put(snapshot->lrc_bo);
kfree(snapshot);
}
+
+u32 xe_lrc_update_timestamp(struct xe_lrc *lrc, u32 *old_ts)
+{
+ *old_ts = lrc->ctx_timestamp;
+
+ lrc->ctx_timestamp = xe_lrc_read_ctx_reg(lrc, CTX_TIMESTAMP);
+
+ return lrc->ctx_timestamp;
+}
diff --git a/drivers/gpu/drm/xe/xe_lrc.h b/drivers/gpu/drm/xe/xe_lrc.h
index e0e841963c23..b9da1031083b 100644
--- a/drivers/gpu/drm/xe/xe_lrc.h
+++ b/drivers/gpu/drm/xe/xe_lrc.h
@@ -66,4 +66,18 @@ void xe_lrc_snapshot_capture_delayed(struct xe_lrc_snapshot *snapshot);
void xe_lrc_snapshot_print(struct xe_lrc_snapshot *snapshot, struct drm_printer *p);
void xe_lrc_snapshot_free(struct xe_lrc_snapshot *snapshot);
+/**
+ * xe_lrc_update_timestamp - readout LRC timestamp and update cached value
+ * @lrc: logical ring context for this exec queue
+ * @old_ts: pointer where to save the previous timestamp
+ *
+ * Read the current timestamp for this LRC and update the cached value. The
+ * previous cached value is also returned in @old_ts so the caller can calculate
+ * the delta between 2 updates. Note that this is not intended to be called from
+ * any place, but just by the paths updating the drm client utilization.
+ *
+ * Returns the current LRC timestamp
+ */
+u32 xe_lrc_update_timestamp(struct xe_lrc *lrc, u32 *old_ts);
+
#endif
diff --git a/drivers/gpu/drm/xe/xe_lrc_types.h b/drivers/gpu/drm/xe/xe_lrc_types.h
index cdbf03faef15..0fa055da6b27 100644
--- a/drivers/gpu/drm/xe/xe_lrc_types.h
+++ b/drivers/gpu/drm/xe/xe_lrc_types.h
@@ -45,6 +45,9 @@ struct xe_lrc {
/** @fence_ctx: context for hw fence */
struct xe_hw_fence_ctx fence_ctx;
+
+ /** @ctx_timestamp: readout value of CTX_TIMESTAMP on last update */
+ u32 ctx_timestamp;
};
struct xe_lrc_snapshot;
--
2.43.0
