drm/i915: Move i915_gpu_error into its own header

Error state management code was moved into separate .c unit
but we didn't move related definitions into own header.

v2: move also intel_display_error_state forward decl
    fix ("Prefer 'unsigned int' to bare use of 'unsigned'")
    warnings detected by checkpatch in moved code (Michal)
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20180308095037.18264-5-michal.wajdeczko@intel.com

drivers/gpu/drm/i915/i915_drv.h

@@ -72,7 +72,7 @@
 #include "i915_gem_object.h"
 #include "i915_gem_gtt.h"
 #include "i915_gem_timeline.h"
-
+#include "i915_gpu_error.h"
 #include "i915_request.h"
 #include "i915_vma.h"
 
@@ -453,172 +453,6 @@ struct intel_csr {
 	uint32_t allowed_dc_mask;
 };
 
-struct intel_display_error_state;
-
-struct i915_gpu_state {
-	struct kref ref;
-	ktime_t time;
-	ktime_t boottime;
-	ktime_t uptime;
-
-	struct drm_i915_private *i915;
-
-	char error_msg[128];
-	bool simulated;
-	bool awake;
-	bool wakelock;
-	bool suspended;
-	int iommu;
-	u32 reset_count;
-	u32 suspend_count;
-	struct intel_device_info device_info;
-	struct intel_driver_caps driver_caps;
-	struct i915_params params;
-
-	struct i915_error_uc {
-		struct intel_uc_fw guc_fw;
-		struct intel_uc_fw huc_fw;
-		struct drm_i915_error_object *guc_log;
-	} uc;
-
-	/* Generic register state */
-	u32 eir;
-	u32 pgtbl_er;
-	u32 ier;
-	u32 gtier[4], ngtier;
-	u32 ccid;
-	u32 derrmr;
-	u32 forcewake;
-	u32 error; /* gen6+ */
-	u32 err_int; /* gen7 */
-	u32 fault_data0; /* gen8, gen9 */
-	u32 fault_data1; /* gen8, gen9 */
-	u32 done_reg;
-	u32 gac_eco;
-	u32 gam_ecochk;
-	u32 gab_ctl;
-	u32 gfx_mode;
-
-	u32 nfence;
-	u64 fence[I915_MAX_NUM_FENCES];
-	struct intel_overlay_error_state *overlay;
-	struct intel_display_error_state *display;
-
-	struct drm_i915_error_engine {
-		int engine_id;
-		/* Software tracked state */
-		bool idle;
-		bool waiting;
-		int num_waiters;
-		unsigned long hangcheck_timestamp;
-		bool hangcheck_stalled;
-		enum intel_engine_hangcheck_action hangcheck_action;
-		struct i915_address_space *vm;
-		int num_requests;
-		u32 reset_count;
-
-		/* position of active request inside the ring */
-		u32 rq_head, rq_post, rq_tail;
-
-		/* our own tracking of ring head and tail */
-		u32 cpu_ring_head;
-		u32 cpu_ring_tail;
-
-		u32 last_seqno;
-
-		/* Register state */
-		u32 start;
-		u32 tail;
-		u32 head;
-		u32 ctl;
-		u32 mode;
-		u32 hws;
-		u32 ipeir;
-		u32 ipehr;
-		u32 bbstate;
-		u32 instpm;
-		u32 instps;
-		u32 seqno;
-		u64 bbaddr;
-		u64 acthd;
-		u32 fault_reg;
-		u64 faddr;
-		u32 rc_psmi; /* sleep state */
-		u32 semaphore_mboxes[I915_NUM_ENGINES - 1];
-		struct intel_instdone instdone;
-
-		struct drm_i915_error_context {
-			char comm[TASK_COMM_LEN];
-			pid_t pid;
-			u32 handle;
-			u32 hw_id;
-			int priority;
-			int ban_score;
-			int active;
-			int guilty;
-			bool bannable;
-		} context;
-
-		struct drm_i915_error_object {
-			u64 gtt_offset;
-			u64 gtt_size;
-			int page_count;
-			int unused;
-			u32 *pages[0];
-		} *ringbuffer, *batchbuffer, *wa_batchbuffer, *ctx, *hws_page;
-
-		struct drm_i915_error_object **user_bo;
-		long user_bo_count;
-
-		struct drm_i915_error_object *wa_ctx;
-		struct drm_i915_error_object *default_state;
-
-		struct drm_i915_error_request {
-			long jiffies;
-			pid_t pid;
-			u32 context;
-			int priority;
-			int ban_score;
-			u32 seqno;
-			u32 head;
-			u32 tail;
-		} *requests, execlist[EXECLIST_MAX_PORTS];
-		unsigned int num_ports;
-
-		struct drm_i915_error_waiter {
-			char comm[TASK_COMM_LEN];
-			pid_t pid;
-			u32 seqno;
-		} *waiters;
-
-		struct {
-			u32 gfx_mode;
-			union {
-				u64 pdp[4];
-				u32 pp_dir_base;
-			};
-		} vm_info;
-	} engine[I915_NUM_ENGINES];
-
-	struct drm_i915_error_buffer {
-		u32 size;
-		u32 name;
-		u32 rseqno[I915_NUM_ENGINES], wseqno;
-		u64 gtt_offset;
-		u32 read_domains;
-		u32 write_domain;
-		s32 fence_reg:I915_MAX_NUM_FENCE_BITS;
-		u32 tiling:2;
-		u32 dirty:1;
-		u32 purgeable:1;
-		u32 userptr:1;
-		s32 engine:4;
-		u32 cache_level:3;
-	} *active_bo[I915_NUM_ENGINES], *pinned_bo;
-	u32 active_bo_count[I915_NUM_ENGINES], pinned_bo_count;
-	struct i915_address_space *active_vm[I915_NUM_ENGINES];
-};
-
 enum i915_cache_level {
 	I915_CACHE_NONE = 0,
 	I915_CACHE_LLC, /* also used for snoopable memory on non-LLC */
@@ -1146,16 +980,6 @@ struct i915_gem_mm {
 	u32 object_count;
 };
 
-struct drm_i915_error_state_buf {
-	struct drm_i915_private *i915;
-	unsigned bytes;
-	unsigned size;
-	int err;
-	u8 *buf;
-	loff_t start;
-	loff_t pos;
-};
-
 #define I915_IDLE_ENGINES_TIMEOUT (200) /* in ms */
 
 #define I915_RESET_TIMEOUT (10 * HZ) /* 10s */
@@ -1164,102 +988,6 @@ struct drm_i915_error_state_buf {
 #define I915_ENGINE_DEAD_TIMEOUT  (4 * HZ)  /* Seqno, head and subunits dead */
 #define I915_SEQNO_DEAD_TIMEOUT   (12 * HZ) /* Seqno dead with active head */
 
-struct i915_gpu_error {
-	/* For hangcheck timer */
-#define DRM_I915_HANGCHECK_PERIOD 1500 /* in ms */
-#define DRM_I915_HANGCHECK_JIFFIES msecs_to_jiffies(DRM_I915_HANGCHECK_PERIOD)
-
-	struct delayed_work hangcheck_work;
-
-	/* For reset and error_state handling. */
-	spinlock_t lock;
-	/* Protected by the above dev->gpu_error.lock. */
-	struct i915_gpu_state *first_error;
-
-	atomic_t pending_fb_pin;
-
-	unsigned long missed_irq_rings;
-
-	/**
-	 * State variable controlling the reset flow and count
-	 *
-	 * This is a counter which gets incremented when reset is triggered,
-	 *
-	 * Before the reset commences, the I915_RESET_BACKOFF bit is set
-	 * meaning that any waiters holding onto the struct_mutex should
-	 * relinquish the lock immediately in order for the reset to start.
-	 *
-	 * If reset is not completed succesfully, the I915_WEDGE bit is
-	 * set meaning that hardware is terminally sour and there is no
-	 * recovery. All waiters on the reset_queue will be woken when
-	 * that happens.
-	 *
-	 * This counter is used by the wait_seqno code to notice that reset
-	 * event happened and it needs to restart the entire ioctl (since most
-	 * likely the seqno it waited for won't ever signal anytime soon).
-	 *
-	 * This is important for lock-free wait paths, where no contended lock
-	 * naturally enforces the correct ordering between the bail-out of the
-	 * waiter and the gpu reset work code.
-	 */
-	unsigned long reset_count;
-
-	/**
-	 * flags: Control various stages of the GPU reset
-	 *
-	 * #I915_RESET_BACKOFF - When we start a reset, we want to stop any
-	 * other users acquiring the struct_mutex. To do this we set the
-	 * #I915_RESET_BACKOFF bit in the error flags when we detect a reset
-	 * and then check for that bit before acquiring the struct_mutex (in
-	 * i915_mutex_lock_interruptible()?). I915_RESET_BACKOFF serves a
-	 * secondary role in preventing two concurrent global reset attempts.
-	 *
-	 * #I915_RESET_HANDOFF - To perform the actual GPU reset, we need the
-	 * struct_mutex. We try to acquire the struct_mutex in the reset worker,
-	 * but it may be held by some long running waiter (that we cannot
-	 * interrupt without causing trouble). Once we are ready to do the GPU
-	 * reset, we set the I915_RESET_HANDOFF bit and wakeup any waiters. If
-	 * they already hold the struct_mutex and want to participate they can
-	 * inspect the bit and do the reset directly, otherwise the worker
-	 * waits for the struct_mutex.
-	 *
-	 * #I915_RESET_ENGINE[num_engines] - Since the driver doesn't need to
-	 * acquire the struct_mutex to reset an engine, we need an explicit
-	 * flag to prevent two concurrent reset attempts in the same engine.
-	 * As the number of engines continues to grow, allocate the flags from
-	 * the most significant bits.
-	 *
-	 * #I915_WEDGED - If reset fails and we can no longer use the GPU,
-	 * we set the #I915_WEDGED bit. Prior to command submission, e.g.
-	 * i915_request_alloc(), this bit is checked and the sequence
-	 * aborted (with -EIO reported to userspace) if set.
-	 */
-	unsigned long flags;
-#define I915_RESET_BACKOFF	0
-#define I915_RESET_HANDOFF	1
-#define I915_RESET_MODESET	2
-#define I915_WEDGED		(BITS_PER_LONG - 1)
-#define I915_RESET_ENGINE	(I915_WEDGED - I915_NUM_ENGINES)
-
-	/** Number of times an engine has been reset */
-	u32 reset_engine_count[I915_NUM_ENGINES];
-
-	/**
-	 * Waitqueue to signal when a hang is detected. Used to for waiters
-	 * to release the struct_mutex for the reset to procede.
-	 */
-	wait_queue_head_t wait_queue;
-
-	/**
-	 * Waitqueue to signal when the reset has completed. Used by clients
-	 * that wait for dev_priv->mm.wedged to settle.
-	 */
-	wait_queue_head_t reset_queue;
-
-	/* For missed irq/seqno simulation. */
-	unsigned long test_irq_rings;
-};
-
 enum modeset_restore {
 	MODESET_ON_LID_OPEN,
 	MODESET_DONE,
@@ -3589,64 +3317,6 @@ static inline int i915_debugfs_connector_add(struct drm_connector *connector)
 static inline void intel_display_crc_init(struct drm_i915_private *dev_priv) {}
 #endif
 
-/* i915_gpu_error.c */
-#if IS_ENABLED(CONFIG_DRM_I915_CAPTURE_ERROR)
-
-__printf(2, 3)
-void i915_error_printf(struct drm_i915_error_state_buf *e, const char *f, ...);
-int i915_error_state_to_str(struct drm_i915_error_state_buf *estr,
-			    const struct i915_gpu_state *gpu);
-int i915_error_state_buf_init(struct drm_i915_error_state_buf *eb,
-			      struct drm_i915_private *i915,
-			      size_t count, loff_t pos);
-static inline void i915_error_state_buf_release(
-	struct drm_i915_error_state_buf *eb)
-{
-	kfree(eb->buf);
-}
-
-struct i915_gpu_state *i915_capture_gpu_state(struct drm_i915_private *i915);
-void i915_capture_error_state(struct drm_i915_private *dev_priv,
-			      u32 engine_mask,
-			      const char *error_msg);
-
-static inline struct i915_gpu_state *
-i915_gpu_state_get(struct i915_gpu_state *gpu)
-{
-	kref_get(&gpu->ref);
-	return gpu;
-}
-
-void __i915_gpu_state_free(struct kref *kref);
-static inline void i915_gpu_state_put(struct i915_gpu_state *gpu)
-{
-	if (gpu)
-		kref_put(&gpu->ref, __i915_gpu_state_free);
-}
-
-struct i915_gpu_state *i915_first_error_state(struct drm_i915_private *i915);
-void i915_reset_error_state(struct drm_i915_private *i915);
-
-#else
-
-static inline void i915_capture_error_state(struct drm_i915_private *dev_priv,
-					    u32 engine_mask,
-					    const char *error_msg)
-{
-}
-
-static inline struct i915_gpu_state *
-i915_first_error_state(struct drm_i915_private *i915)
-{
-	return NULL;
-}
-
-static inline void i915_reset_error_state(struct drm_i915_private *i915)
-{
-}
-
-#endif
-
 const char *i915_cache_level_str(struct drm_i915_private *i915, int type);
 
 /* i915_cmd_parser.c */

drivers/gpu/drm/i915/i915_gpu_error.c

@@ -32,6 +32,7 @@
 #include <linux/zlib.h>
 #include <drm/drm_print.h>
 
+#include "i915_gpu_error.h"
 #include "i915_drv.h"
 
 static inline const struct intel_engine_cs *

drivers/gpu/drm/i915/i915_gpu_error.h

+/*
+ * SPDX-License-Identifier: MIT
+ *
+ * Copyright � 2008-2018 Intel Corporation
+ */
+
+#ifndef _I915_GPU_ERROR_H_
+#define _I915_GPU_ERROR_H_
+
+#include <linux/kref.h>
+#include <linux/ktime.h>
+#include <linux/sched.h>
+
+#include <drm/drm_mm.h>
+
+#include "intel_device_info.h"
+#include "intel_ringbuffer.h"
+#include "intel_uc_fw.h"
+
+#include "i915_gem.h"
+#include "i915_gem_gtt.h"
+#include "i915_params.h"
+
+struct drm_i915_private;
+struct intel_overlay_error_state;
+struct intel_display_error_state;
+
+struct i915_gpu_state {
+	struct kref ref;
+	ktime_t time;
+	ktime_t boottime;
+	ktime_t uptime;
+
+	struct drm_i915_private *i915;
+
+	char error_msg[128];
+	bool simulated;
+	bool awake;
+	bool wakelock;
+	bool suspended;
+	int iommu;
+	u32 reset_count;
+	u32 suspend_count;
+	struct intel_device_info device_info;
+	struct intel_driver_caps driver_caps;
+	struct i915_params params;
+
+	struct i915_error_uc {
+		struct intel_uc_fw guc_fw;
+		struct intel_uc_fw huc_fw;
+		struct drm_i915_error_object *guc_log;
+	} uc;
+
+	/* Generic register state */
+	u32 eir;
+	u32 pgtbl_er;
+	u32 ier;
+	u32 gtier[4], ngtier;
+	u32 ccid;
+	u32 derrmr;
+	u32 forcewake;
+	u32 error; /* gen6+ */
+	u32 err_int; /* gen7 */
+	u32 fault_data0; /* gen8, gen9 */
+	u32 fault_data1; /* gen8, gen9 */
+	u32 done_reg;
+	u32 gac_eco;
+	u32 gam_ecochk;
+	u32 gab_ctl;
+	u32 gfx_mode;
+
+	u32 nfence;
+	u64 fence[I915_MAX_NUM_FENCES];
+	struct intel_overlay_error_state *overlay;
+	struct intel_display_error_state *display;
+
+	struct drm_i915_error_engine {
+		int engine_id;
+		/* Software tracked state */
+		bool idle;
+		bool waiting;
+		int num_waiters;
+		unsigned long hangcheck_timestamp;
+		bool hangcheck_stalled;
+		enum intel_engine_hangcheck_action hangcheck_action;
+		struct i915_address_space *vm;
+		int num_requests;
+		u32 reset_count;
+
+		/* position of active request inside the ring */
+		u32 rq_head, rq_post, rq_tail;
+
+		/* our own tracking of ring head and tail */
+		u32 cpu_ring_head;
+		u32 cpu_ring_tail;
+
+		u32 last_seqno;
+
+		/* Register state */
+		u32 start;
+		u32 tail;
+		u32 head;
+		u32 ctl;
+		u32 mode;
+		u32 hws;
+		u32 ipeir;
+		u32 ipehr;
+		u32 bbstate;
+		u32 instpm;
+		u32 instps;
+		u32 seqno;
+		u64 bbaddr;
+		u64 acthd;
+		u32 fault_reg;
+		u64 faddr;
+		u32 rc_psmi; /* sleep state */
+		u32 semaphore_mboxes[I915_NUM_ENGINES - 1];
+		struct intel_instdone instdone;
+
+		struct drm_i915_error_context {
+			char comm[TASK_COMM_LEN];
+			pid_t pid;
+			u32 handle;
+			u32 hw_id;
+			int priority;
+			int ban_score;
+			int active;
+			int guilty;
+			bool bannable;
+		} context;
+
+		struct drm_i915_error_object {
+			u64 gtt_offset;
+			u64 gtt_size;
+			int page_count;
+			int unused;
+			u32 *pages[0];
+		} *ringbuffer, *batchbuffer, *wa_batchbuffer, *ctx, *hws_page;
+
+		struct drm_i915_error_object **user_bo;
+		long user_bo_count;
+
+		struct drm_i915_error_object *wa_ctx;
+		struct drm_i915_error_object *default_state;
+
+		struct drm_i915_error_request {
+			long jiffies;
+			pid_t pid;
+			u32 context;
+			int priority;
+			int ban_score;
+			u32 seqno;
+			u32 head;
+			u32 tail;
+		} *requests, execlist[EXECLIST_MAX_PORTS];
+		unsigned int num_ports;
+
+		struct drm_i915_error_waiter {
+			char comm[TASK_COMM_LEN];
+			pid_t pid;
+			u32 seqno;
+		} *waiters;
+
+		struct {
+			u32 gfx_mode;
+			union {
+				u64 pdp[4];
+				u32 pp_dir_base;
+			};
+		} vm_info;
+	} engine[I915_NUM_ENGINES];
+
+	struct drm_i915_error_buffer {
+		u32 size;
+		u32 name;
+		u32 rseqno[I915_NUM_ENGINES], wseqno;
+		u64 gtt_offset;
+		u32 read_domains;
+		u32 write_domain;
+		s32 fence_reg:I915_MAX_NUM_FENCE_BITS;
+		u32 tiling:2;
+		u32 dirty:1;
+		u32 purgeable:1;
+		u32 userptr:1;
+		s32 engine:4;
+		u32 cache_level:3;
+	} *active_bo[I915_NUM_ENGINES], *pinned_bo;
+	u32 active_bo_count[I915_NUM_ENGINES], pinned_bo_count;
+	struct i915_address_space *active_vm[I915_NUM_ENGINES];
+};
+
+struct i915_gpu_error {
+	/* For hangcheck timer */
+#define DRM_I915_HANGCHECK_PERIOD 1500 /* in ms */
+#define DRM_I915_HANGCHECK_JIFFIES msecs_to_jiffies(DRM_I915_HANGCHECK_PERIOD)
+
+	struct delayed_work hangcheck_work;
+
+	/* For reset and error_state handling. */
+	spinlock_t lock;
+	/* Protected by the above dev->gpu_error.lock. */
+	struct i915_gpu_state *first_error;
+
+	atomic_t pending_fb_pin;
+
+	unsigned long missed_irq_rings;
+
+	/**
+	 * State variable controlling the reset flow and count
+	 *
+	 * This is a counter which gets incremented when reset is triggered,
+	 *
+	 * Before the reset commences, the I915_RESET_BACKOFF bit is set
+	 * meaning that any waiters holding onto the struct_mutex should
+	 * relinquish the lock immediately in order for the reset to start.
+	 *
+	 * If reset is not completed successfully, the I915_WEDGE bit is
+	 * set meaning that hardware is terminally sour and there is no
+	 * recovery. All waiters on the reset_queue will be woken when
+	 * that happens.
+	 *
+	 * This counter is used by the wait_seqno code to notice that reset
+	 * event happened and it needs to restart the entire ioctl (since most
+	 * likely the seqno it waited for won't ever signal anytime soon).
+	 *
+	 * This is important for lock-free wait paths, where no contended lock
+	 * naturally enforces the correct ordering between the bail-out of the
+	 * waiter and the gpu reset work code.
+	 */
+	unsigned long reset_count;
+
+	/**
+	 * flags: Control various stages of the GPU reset
+	 *
+	 * #I915_RESET_BACKOFF - When we start a reset, we want to stop any
+	 * other users acquiring the struct_mutex. To do this we set the
+	 * #I915_RESET_BACKOFF bit in the error flags when we detect a reset
+	 * and then check for that bit before acquiring the struct_mutex (in
+	 * i915_mutex_lock_interruptible()?). I915_RESET_BACKOFF serves a
+	 * secondary role in preventing two concurrent global reset attempts.
+	 *
+	 * #I915_RESET_HANDOFF - To perform the actual GPU reset, we need the
+	 * struct_mutex. We try to acquire the struct_mutex in the reset worker,
+	 * but it may be held by some long running waiter (that we cannot
+	 * interrupt without causing trouble). Once we are ready to do the GPU
+	 * reset, we set the I915_RESET_HANDOFF bit and wakeup any waiters. If
+	 * they already hold the struct_mutex and want to participate they can
+	 * inspect the bit and do the reset directly, otherwise the worker
+	 * waits for the struct_mutex.
+	 *
+	 * #I915_RESET_ENGINE[num_engines] - Since the driver doesn't need to
+	 * acquire the struct_mutex to reset an engine, we need an explicit
+	 * flag to prevent two concurrent reset attempts in the same engine.
+	 * As the number of engines continues to grow, allocate the flags from
+	 * the most significant bits.
+	 *
+	 * #I915_WEDGED - If reset fails and we can no longer use the GPU,
+	 * we set the #I915_WEDGED bit. Prior to command submission, e.g.
+	 * i915_request_alloc(), this bit is checked and the sequence
+	 * aborted (with -EIO reported to userspace) if set.
+	 */
+	unsigned long flags;
+#define I915_RESET_BACKOFF	0
+#define I915_RESET_HANDOFF	1
+#define I915_RESET_MODESET	2
+#define I915_WEDGED		(BITS_PER_LONG - 1)
+#define I915_RESET_ENGINE	(I915_WEDGED - I915_NUM_ENGINES)
+
+	/** Number of times an engine has been reset */
+	u32 reset_engine_count[I915_NUM_ENGINES];
+
+	/**
+	 * Waitqueue to signal when a hang is detected. Used to for waiters
+	 * to release the struct_mutex for the reset to procede.
+	 */
+	wait_queue_head_t wait_queue;
+
+	/**
+	 * Waitqueue to signal when the reset has completed. Used by clients
+	 * that wait for dev_priv->mm.wedged to settle.
+	 */
+	wait_queue_head_t reset_queue;
+
+	/* For missed irq/seqno simulation. */
+	unsigned long test_irq_rings;
+};
+
+struct drm_i915_error_state_buf {
+	struct drm_i915_private *i915;
+	unsigned int bytes;
+	unsigned int size;
+	int err;
+	u8 *buf;
+	loff_t start;
+	loff_t pos;
+};
+
+#if IS_ENABLED(CONFIG_DRM_I915_CAPTURE_ERROR)
+
+__printf(2, 3)
+void i915_error_printf(struct drm_i915_error_state_buf *e, const char *f, ...);
+int i915_error_state_to_str(struct drm_i915_error_state_buf *estr,
+			    const struct i915_gpu_state *gpu);
+int i915_error_state_buf_init(struct drm_i915_error_state_buf *eb,
+			      struct drm_i915_private *i915,
+			      size_t count, loff_t pos);
+
+static inline void
+i915_error_state_buf_release(struct drm_i915_error_state_buf *eb)
+{
+	kfree(eb->buf);
+}
+
+struct i915_gpu_state *i915_capture_gpu_state(struct drm_i915_private *i915);
+void i915_capture_error_state(struct drm_i915_private *dev_priv,
+			      u32 engine_mask,
+			      const char *error_msg);
+
+static inline struct i915_gpu_state *
+i915_gpu_state_get(struct i915_gpu_state *gpu)
+{
+	kref_get(&gpu->ref);
+	return gpu;
+}
+
+void __i915_gpu_state_free(struct kref *kref);
+static inline void i915_gpu_state_put(struct i915_gpu_state *gpu)
+{
+	if (gpu)
+		kref_put(&gpu->ref, __i915_gpu_state_free);
+}
+
+struct i915_gpu_state *i915_first_error_state(struct drm_i915_private *i915);
+void i915_reset_error_state(struct drm_i915_private *i915);
+
+#else
+
+static inline void i915_capture_error_state(struct drm_i915_private *dev_priv,
+					    u32 engine_mask,
+					    const char *error_msg)
+{
+}
+
+static inline struct i915_gpu_state *
+i915_first_error_state(struct drm_i915_private *i915)
+{
+	return NULL;
+}
+
+static inline void i915_reset_error_state(struct drm_i915_private *i915)
+{
+}
+
+#endif /* IS_ENABLED(CONFIG_DRM_I915_CAPTURE_ERROR) */
+
+#endif /* _I915_GPU_ERROR_H_ */