[PATCH 19/22] drm/xe/eudebug: Add read/count/compare helper for eu attention

[Mika Kuoppala <mika.kuoppala@linux.intel.com>]

From: Gwan-gyeong Mun <gwan-gyeong.mun@intel.com>

Add xe_eu_attentions structure to capture and store eu attention bits.
Add a function to count the number of eu threads that have turned on from
eu attentions, and add a function to count the number of eu threads that
have changed on a state between eu attentions.

v2: fix array size calculation (Christoph)

Signed-off-by: Gwan-gyeong Mun <gwan-gyeong.mun@intel.com>
Signed-off-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
---
 drivers/gpu/drm/xe/xe_gt_debug.c       | 65 ++++++++++++++++++++++++++
 drivers/gpu/drm/xe/xe_gt_debug.h       |  7 +++
 drivers/gpu/drm/xe/xe_gt_debug_types.h | 23 +++++++++
 3 files changed, 95 insertions(+)
 create mode 100644 drivers/gpu/drm/xe/xe_gt_debug_types.h

diff --git a/drivers/gpu/drm/xe/xe_gt_debug.c b/drivers/gpu/drm/xe/xe_gt_debug.c
index 314eef6734c3..bf2ca95c7389 100644
--- a/drivers/gpu/drm/xe/xe_gt_debug.c
+++ b/drivers/gpu/drm/xe/xe_gt_debug.c
@@ -3,12 +3,14 @@
  * Copyright © 2023 Intel Corporation
  */
 
+#include <linux/delay.h>
 #include "regs/xe_gt_regs.h"
 #include "xe_device.h"
 #include "xe_force_wake.h"
 #include "xe_gt.h"
 #include "xe_gt_topology.h"
 #include "xe_gt_debug.h"
+#include "xe_gt_debug_types.h"
 #include "xe_gt_mcr.h"
 #include "xe_pm.h"
 #include "xe_macros.h"
@@ -177,3 +179,66 @@ int xe_gt_eu_threads_needing_attention(struct xe_gt *gt)
 
 	return err < 0 ? 0 : err;
 }
+
+static inline unsigned int
+xe_eu_attentions_count(const struct xe_eu_attentions *a)
+{
+	return bitmap_weight((void *)a->att, a->size * BITS_PER_BYTE);
+}
+
+void xe_gt_eu_attentions_read(struct xe_gt *gt,
+			      struct xe_eu_attentions *a,
+			      const unsigned int settle_time_ms)
+{
+	unsigned int prev = 0;
+	ktime_t end, now;
+
+	now = ktime_get_raw();
+	end = ktime_add_ms(now, settle_time_ms);
+
+	a->ts = 0;
+	a->size = min_t(int,
+			xe_gt_eu_attention_bitmap_size(gt),
+			sizeof(a->att));
+
+	do {
+		unsigned int attn;
+
+		xe_gt_eu_attention_bitmap(gt, a->att, a->size);
+		attn = xe_eu_attentions_count(a);
+
+		now = ktime_get_raw();
+
+		if (a->ts == 0)
+			a->ts = now;
+		else if (attn && attn != prev)
+			a->ts = now;
+
+		prev = attn;
+
+		if (settle_time_ms)
+			udelay(5);
+
+		/*
+		 * XXX We are gathering data for production SIP to find
+		 * the upper limit of settle time. For now, we wait full
+		 * timeout value regardless.
+		 */
+	} while (ktime_before(now, end));
+}
+
+unsigned int xe_eu_attentions_xor_count(const struct xe_eu_attentions *a,
+					const struct xe_eu_attentions *b)
+{
+	unsigned int count = 0;
+	unsigned int i;
+
+	if (XE_WARN_ON(a->size != b->size))
+		return -EINVAL;
+
+	for (i = 0; i < a->size; i++)
+		if (a->att[i] ^ b->att[i])
+			count++;
+
+	return count;
+}
diff --git a/drivers/gpu/drm/xe/xe_gt_debug.h b/drivers/gpu/drm/xe/xe_gt_debug.h
index 9dabe9cc1d25..0d03565195b4 100644
--- a/drivers/gpu/drm/xe/xe_gt_debug.h
+++ b/drivers/gpu/drm/xe/xe_gt_debug.h
@@ -9,6 +9,7 @@
 #include <linux/bits.h>
 #include <linux/math.h>
 
+struct xe_eu_attentions;
 struct xe_gt;
 
 #define XE_GT_ATTENTION_TIMEOUT_MS 100
@@ -29,4 +30,10 @@ int xe_gt_eu_attention_bitmap_size(struct xe_gt *gt);
 int xe_gt_eu_attention_bitmap(struct xe_gt *gt, u8 *bits,
 			      unsigned int bitmap_size);
 
+void xe_gt_eu_attentions_read(struct xe_gt *gt,
+			      struct xe_eu_attentions *a,
+			      const unsigned int settle_time_ms);
+
+unsigned int xe_eu_attentions_xor_count(const struct xe_eu_attentions *a,
+					const struct xe_eu_attentions *b);
 #endif
diff --git a/drivers/gpu/drm/xe/xe_gt_debug_types.h b/drivers/gpu/drm/xe/xe_gt_debug_types.h
new file mode 100644
index 000000000000..35a0e822f20a
--- /dev/null
+++ b/drivers/gpu/drm/xe/xe_gt_debug_types.h
@@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: MIT */
+/*
+ * Copyright © 2025 Intel Corporation
+ */
+
+#ifndef __XE_GT_DEBUG_TYPES_
+#define __XE_GT_DEBUG_TYPES_
+
+#include <linux/types.h>
+
+#define XE_GT_EU_ATT_ROWS 2u
+#define XE_GT_EU_ATT_MAX_THREADS 16
+#define XE_GT_EU_MAX_NUM  1024
+
+struct xe_eu_attentions {
+	u8 att[XE_GT_EU_MAX_NUM *
+	       XE_GT_EU_ATT_ROWS *
+	       XE_GT_EU_ATT_MAX_THREADS/8];
+	unsigned int size;
+	ktime_t ts;
+};
+
+#endif
-- 
2.43.0