drm/asahi: add G17 accounting and fix GPU resource lifetimes

Documentation/ABI/testing/sysfs-driver-asahi

@@ -0,0 +1,54 @@
+What:           /sys/devices/platform/.../*.gpu/agx_stats
+Date:           October 2026
+Contact:        Aurora Silicon developers
+Description:
+                Read-only, per-device firmware GPU utilization on T8140 G17P.
+                With asahi.stats_export=0, the file reports unsupported.
+                The default value 1 enables the version 2 export described here.
+                Earlier GPU generations use the separate legacy agx_stats format.
+                Version 2 is a whitespace-delimited key/value format. Readers
+                must check the version and load_valid before using percentages.
+
+                version: 2
+                source: firmware
+                load_valid: 1 if the current utilization is available, else 0
+                busy_percent: firmware aggregate utilization, percent (0..100)
+                util1..util3: firmware engine percentages (0..100); engine labels
+                             are not assigned without independent validation
+                util4: same aggregate as busy_percent; do not sum engine values
+                gpu_power_known: whether a timestamped power state was received
+                gpu_powered: 0 when firmware reports the GPU powered off, else 1
+                samples: accepted primary utilization reports since probe
+                sample_received_ns: host CLOCK_MONOTONIC receive timestamp
+                sample_age_ns: time since the retained utilization report
+                sample_timestamp_ticks: 64-bit firmware utilization timestamp
+                power_timestamp_ticks: newest secondary power-state timestamp
+                clock_hz: 24000000 (timestamp and residency ticks)
+                powered_ticks: completed powered intervals, accumulated from
+                               firmware power-off records since probe
+                unpowered_ticks: completed unpowered intervals, accumulated from
+                                 firmware power-on records since probe
+                invalid_samples: malformed utilization/power records rejected
+
+                A timestamped power-off witness overrides retained utilization
+                with zero. After wake, an old utilization report is unavailable
+                until a report for the new interval arrives. Device loss or
+                shutdown invalidates load until a new device is probed. Receive timestamps
+                do not order events across firmware rings: firmware timestamps
+                determine which state is newer. Suspend can separate the host
+                and firmware clocks; do not subtract values from those domains.
+
+                Power residency is not GPU busy time. Residency counters omit
+                the currently open power interval and saturate at U64_MAX.
+                Neither these counters nor the percentages are per-client DRM
+                engine execution time. No per-client execution counter is
+                synthesized from queue admission, wall time or job spans.
+
+                Reading debugfs asahi-g17/statistics requests two seconds of full
+                raw-payload capture, including undecoded record kinds. Repeat
+                reads to keep diagnostic capture active. It is disabled by
+                default and is not needed for normal utilization reporting.
+                Trace records and uncaptured statistics only read required words.
+                Captured counts exclude records outside the capture window. That diagnostic format is not a
+                stable userspace ABI. Optional telemetry registration failure
+                does not prevent GPU initialization and is logged by the driver.

Documentation/ABI/testing/sysfs-driver-asahi-agx-stats

@@ -2,6 +2,9 @@ What:		/sys/class/drm/card*/device/agx_stats
 Date:		October 2026
 Contact:	Asahi Linux GPU driver maintainers
 Description:
+		Legacy GPU format. For T8140 G17P, see sysfs-driver-asahi
+		for the version 2 format and power-state validity rules.
+
 		Read-only dump of the AGX firmware statistics decoded by the
 		drm/asahi driver. The driver already polls the firmware statistics
 		ring (see `drivers/gpu/drm/asahi/channel.rs::StatsChannel::poll`,

drivers/base/base.h

@@ -222,6 +222,8 @@ typedef void (*dr_node_free_t)(struct devres_node *node);
 
 struct devres_node {
 	struct list_head		entry;
+	/* Device-list membership, cleared under devres_lock before detachment. */
+	struct device			*owner;
 	dr_node_release_t		release;
 	dr_node_free_t			free_node;
 	const char			*name;

drivers/base/devres.c

@@ -41,6 +41,7 @@ void devres_node_init(struct devres_node *node,
 		      dr_node_free_t free_node)
 {
 	INIT_LIST_HEAD(&node->entry);
+	WRITE_ONCE(node->owner, NULL);
 	node->release = release;
 	node->free_node = free_node;
 }
@@ -156,6 +157,7 @@ static void add_dr(struct device *dev, struct devres_node *node)
 	devres_log(dev, node, "ADD");
 	BUG_ON(!list_empty(&node->entry));
 	list_add_tail(&node->entry, &dev->devres_head);
+	WRITE_ONCE(node->owner, dev);
 }
 
 static void replace_dr(struct device *dev,
@@ -164,6 +166,8 @@ static void replace_dr(struct device *dev,
 	devres_log(dev, old, "REPLACE");
 	BUG_ON(!list_empty(&new->entry));
 	list_replace(&old->entry, &new->entry);
+	WRITE_ONCE(old->owner, NULL);
+	WRITE_ONCE(new->owner, dev);
 }
 
 /**
@@ -367,18 +371,14 @@ EXPORT_SYMBOL_GPL(devres_get);
 
 bool devres_node_remove(struct device *dev, struct devres_node *node)
 {
-	struct devres_node *__node;
-
 	guard(spinlock_irqsave)(&dev->devres_lock);
-	list_for_each_entry_reverse(__node, &dev->devres_head, entry) {
-		if (__node == node) {
-			list_del_init(&node->entry);
-			devres_log(dev, node, "REM");
-			return true;
-		}
-	}
-
-	return false;
+	/* A release-all/group pass may own a detached node on its private list. */
+	if (READ_ONCE(node->owner) != dev)
+		return false;
+	list_del_init(&node->entry);
+	WRITE_ONCE(node->owner, NULL);
+	devres_log(dev, node, "REM");
+	return true;
 }
 
 /**
@@ -405,6 +405,7 @@ void *devres_remove(struct device *dev, dr_release_t release,
 	dr = find_dr(dev, release, match, match_data);
 	if (dr) {
 		list_del_init(&dr->node.entry);
+		WRITE_ONCE(dr->node.owner, NULL);
 		devres_log(dev, &dr->node, "REM");
 		return dr->data;
 	}
@@ -500,6 +501,7 @@ static int remove_nodes(struct device *dev,
 			if (&node->entry == first)
 				first = first->next;
 			list_move_tail(&node->entry, todo);
+			WRITE_ONCE(node->owner, NULL);
 			cnt++;
 		}
 	}
@@ -530,7 +532,9 @@ static int remove_nodes(struct device *dev,
 			 * nodes are always before both.
 			 */
 			list_move_tail(&grp->node[0].entry, todo);
+			WRITE_ONCE(grp->node[0].owner, NULL);
 			list_del_init(&grp->node[1].entry);
+			WRITE_ONCE(grp->node[1].owner, NULL);
 		}
 	}
 
@@ -685,7 +689,9 @@ void devres_remove_group(struct device *dev, void *id)
 	grp = find_group(dev, id);
 	if (grp) {
 		list_del_init(&grp->node[0].entry);
+		WRITE_ONCE(grp->node[0].owner, NULL);
 		list_del_init(&grp->node[1].entry);
+		WRITE_ONCE(grp->node[1].owner, NULL);
 		devres_log(dev, &grp->node[0], "REM");
 	} else
 		WARN_ON(1);
@@ -849,6 +855,7 @@ static struct devres_action *remove_action(struct device *dev,
 		return ERR_PTR(-ENOENT);
 
 	list_del_init(&dr->node.entry);
+	WRITE_ONCE(dr->node.owner, NULL);
 	devres_log(dev, &dr->node, "REM");
 
 	return dr;

drivers/gpu/drm/asahi/Makefile

@@ -1,4 +1,4 @@
 # SPDX-License-Identifier: GPL-2.0
 
 obj-$(CONFIG_DRM_ASAHI) += asahi.o
-asahi-y := asahi_core.o sysfs.o
+asahi-y := asahi_core.o sysfs.o asahi_telemetry.o