1 files changed, 334 insertions, 74 deletions

diff --git a/drivers/gpu/drm/i915/i915_gpu_error.c b/drivers/gpu/drm/i915/i915_gpu_error.c
index 4008bb09fdb5..7582ef34bf3f 100644
--- a/drivers/gpu/drm/i915/i915_gpu_error.c
+++ b/drivers/gpu/drm/i915/i915_gpu_error.c
@@ -28,6 +28,7 @@
  */
 
 #include <linux/ascii85.h>
+#include <linux/debugfs.h>
 #include <linux/highmem.h>
 #include <linux/nmi.h>
 #include <linux/pagevec.h>
@@ -39,8 +40,7 @@
 #include <drm/drm_cache.h>
 #include <drm/drm_print.h>
 
-#include "display/intel_dmc.h"
-#include "display/intel_overlay.h"
+#include "display/intel_display_snapshot.h"
 
 #include "gem/i915_gem_context.h"
 #include "gem/i915_gem_lmem.h"
@@ -57,6 +57,7 @@
 #include "i915_memcpy.h"
 #include "i915_reg.h"
 #include "i915_scatterlist.h"
+#include "i915_sysfs.h"
 #include "i915_utils.h"
 
 #define ALLOW_FAIL (__GFP_KSWAPD_RECLAIM | __GFP_RETRY_MAYFAIL | __GFP_NOWARN)
@@ -520,7 +521,7 @@ __find_vma(struct i915_vma_coredump *vma, const char *name)
 	return NULL;
 }
 
-struct i915_vma_coredump *
+static struct i915_vma_coredump *
 intel_gpu_error_find_batch(const struct intel_engine_coredump *ee)
 {
 	return __find_vma(ee->vma, "batch");
@@ -609,9 +610,9 @@ void i915_error_printf(struct drm_i915_error_state_buf *e, const char *f, ...)
 	va_end(args);
 }
 
-void intel_gpu_error_print_vma(struct drm_i915_error_state_buf *m,
-			       const struct intel_engine_cs *engine,
-			       const struct i915_vma_coredump *vma)
+static void intel_gpu_error_print_vma(struct drm_i915_error_state_buf *m,
+				      const struct intel_engine_cs *engine,
+				      const struct i915_vma_coredump *vma)
 {
 	char out[ASCII85_BUFSZ];
 	struct page *page;
@@ -649,8 +650,6 @@ static void err_print_capabilities(struct drm_i915_error_state_buf *m,
 	struct drm_printer p = i915_error_printer(m);
 
 	intel_device_info_print(&error->device_info, &error->runtime_info, &p);
-	intel_display_device_info_print(&error->display_device_info,
-					&error->display_runtime_info, &p);
 	intel_driver_caps_print(&error->driver_caps, &p);
 }
 
@@ -686,6 +685,74 @@ static void err_print_guc_ctb(struct drm_i915_error_state_buf *m,
 		   ctb->head, ctb->tail, ctb->desc_offset, ctb->cmds_offset, ctb->size);
 }
 
+/* This list includes registers that are useful in debugging GuC hangs. */
+const struct {
+	u32 start;
+	u32 count;
+} guc_hw_reg_state[] = {
+	{ 0xc0b0, 2 },
+	{ 0xc000, 65 },
+	{ 0xc140, 1 },
+	{ 0xc180, 16 },
+	{ 0xc1dc, 10 },
+	{ 0xc300, 79 },
+	{ 0xc4b4, 47 },
+	{ 0xc574, 1 },
+	{ 0xc57c, 1 },
+	{ 0xc584, 11 },
+	{ 0xc5c0, 8 },
+	{ 0xc5e4, 1 },
+	{ 0xc5ec, 103 },
+	{ 0xc7c0, 1 },
+	{ 0xc0b0, 2 }
+};
+
+static u32 print_range_line(struct drm_i915_error_state_buf *m, u32 start, u32 *dump, u32 count)
+{
+	if (count >= 8) {
+		err_printf(m, "[0x%04x] 0x%08x 0x%08x 0x%08x 0x%08x 0x%08x 0x%08x 0x%08x 0x%08x\n",
+			   start, dump[0], dump[1], dump[2], dump[3],
+			   dump[4], dump[5], dump[6], dump[7]);
+		return 8;
+	} else if (count >= 4) {
+		err_printf(m, "[0x%04x] 0x%08x 0x%08x 0x%08x 0x%08x\n",
+			   start, dump[0], dump[1], dump[2], dump[3]);
+		return 4;
+	} else if (count >= 2) {
+		err_printf(m, "[0x%04x] 0x%08x 0x%08x\n", start, dump[0], dump[1]);
+		return 2;
+	}
+
+	err_printf(m, "[0x%04x] 0x%08x\n", start, dump[0]);
+	return 1;
+}
+
+static void err_print_guc_hw_state(struct drm_i915_error_state_buf *m, u32 *hw_state)
+{
+	u32 total = 0;
+	int i;
+
+	if (!hw_state)
+		return;
+
+	err_printf(m, "GuC Register State:\n");
+
+	for (i = 0; i < ARRAY_SIZE(guc_hw_reg_state); i++) {
+		u32 entry = 0;
+
+		while (entry < guc_hw_reg_state[i].count) {
+			u32 start = guc_hw_reg_state[i].start + entry * sizeof(u32);
+			u32 count = guc_hw_reg_state[i].count - entry;
+			u32 *values = hw_state + total + entry;
+
+			entry += print_range_line(m, start, values, count);
+		}
+
+		GEM_BUG_ON(entry != guc_hw_reg_state[i].count);
+		total += entry;
+	}
+}
+
 static void err_print_uc(struct drm_i915_error_state_buf *m,
 			 const struct intel_uc_coredump *error_uc)
 {
@@ -694,6 +761,7 @@ static void err_print_uc(struct drm_i915_error_state_buf *m,
 	intel_uc_fw_dump(&error_uc->guc_fw, &p);
 	intel_uc_fw_dump(&error_uc->huc_fw, &p);
 	err_printf(m, "GuC timestamp: 0x%08x\n", error_uc->guc.timestamp);
+	err_print_guc_hw_state(m, error_uc->guc.hw_state);
 	intel_gpu_error_print_vma(m, NULL, error_uc->guc.vma_log);
 	err_printf(m, "GuC CTB fence: %d\n", error_uc->guc.last_fence);
 	err_print_guc_ctb(m, "Send", error_uc->guc.ctb + 0);
@@ -727,13 +795,6 @@ static void err_print_gt_info(struct drm_i915_error_state_buf *m,
 	intel_sseu_print_topology(gt->_gt->i915, &gt->info.sseu, &p);
 }
 
-static void err_print_gt_display(struct drm_i915_error_state_buf *m,
-				 struct intel_gt_coredump *gt)
-{
-	err_printf(m, "IER: 0x%08x\n", gt->ier);
-	err_printf(m, "DERRMR: 0x%08x\n", gt->derrmr);
-}
-
 static void err_print_gt_global_nonguc(struct drm_i915_error_state_buf *m,
 				       struct intel_gt_coredump *gt)
 {
@@ -833,6 +894,7 @@ static void err_print_gt_engines(struct drm_i915_error_state_buf *m,
 static void __err_print_to_sgl(struct drm_i915_error_state_buf *m,
 			       struct i915_gpu_coredump *error)
 {
+	struct drm_printer p = i915_error_printer(m);
 	const struct intel_engine_coredump *ee;
 	struct timespec64 ts;
 
@@ -841,7 +903,6 @@ static void __err_print_to_sgl(struct drm_i915_error_state_buf *m,
 	err_printf(m, "Kernel: %s %s\n",
 		   init_utsname()->release,
 		   init_utsname()->machine);
-	err_printf(m, "Driver: %s\n", DRIVER_DATE);
 	ts = ktime_to_timespec64(error->time);
 	err_printf(m, "Time: %lld s %ld us\n",
 		   (s64)ts.tv_sec, ts.tv_nsec / NSEC_PER_USEC);
@@ -870,8 +931,6 @@ static void __err_print_to_sgl(struct drm_i915_error_state_buf *m,
 
 	err_printf(m, "IOMMU enabled?: %d\n", error->iommu);
 
-	intel_dmc_print_error_state(m, m->i915);
-
 	err_printf(m, "RPM wakelock: %s\n", str_yes_no(error->wakelock));
 	err_printf(m, "PM suspended: %s\n", str_yes_no(error->suspended));
 
@@ -881,7 +940,6 @@ static void __err_print_to_sgl(struct drm_i915_error_state_buf *m,
 		if (error->gt->uc && error->gt->uc->guc.is_guc_capture)
 			print_guc_capture = true;
 
-		err_print_gt_display(m, error->gt);
 		err_print_gt_global_nonguc(m, error->gt);
 		err_print_gt_fences(m, error->gt);
 
@@ -900,11 +958,10 @@ static void __err_print_to_sgl(struct drm_i915_error_state_buf *m,
 		err_print_gt_info(m, error->gt);
 	}
 
-	if (error->overlay)
-		intel_overlay_print_error_state(m, error->overlay);
-
 	err_print_capabilities(m, error);
 	err_print_params(m, &error->params);
+
+	intel_display_snapshot_print(error->display_snapshot, &p);
 }
 
 static int err_print_to_sgl(struct i915_gpu_coredump *error)
@@ -1037,6 +1094,7 @@ static void cleanup_uc(struct intel_uc_coredump *uc)
 	kfree(uc->huc_fw.file_wanted.path);
 	i915_vma_coredump_free(uc->guc.vma_log);
 	i915_vma_coredump_free(uc->guc.vma_ctb);
+	kfree(uc->guc.hw_state);
 
 	kfree(uc);
 }
@@ -1071,7 +1129,7 @@ void __i915_gpu_coredump_free(struct kref *error_ref)
 		cleanup_gt(gt);
 	}
 
-	kfree(error->overlay);
+	intel_display_snapshot_free(error->display_snapshot);
 
 	cleanup_params(error);
 
@@ -1107,7 +1165,7 @@ i915_vma_coredump_create(const struct intel_gt *gt,
 	}
 
 	INIT_LIST_HEAD(&dst->page_list);
-	strcpy(dst->name, name);
+	strscpy(dst->name, name);
 	dst->next = NULL;
 
 	dst->gtt_offset = vma_res->start;
@@ -1154,7 +1212,7 @@ i915_vma_coredump_create(const struct intel_gt *gt,
 			dma_addr_t offset = dma - mem->region.start;
 			void __iomem *s;
 
-			if (offset + PAGE_SIZE > mem->io_size) {
+			if (offset + PAGE_SIZE > resource_size(&mem->io)) {
 				ret = -EINVAL;
 				break;
 			}
@@ -1234,7 +1292,15 @@ static void engine_record_registers(struct intel_engine_coredump *ee)
 	if (GRAPHICS_VER(i915) >= 6) {
 		ee->rc_psmi = ENGINE_READ(engine, RING_PSMI_CTL);
 
-		if (GRAPHICS_VER_FULL(i915) >= IP_VER(12, 50))
+		/*
+		 * For the media GT, this ring fault register is not replicated,
+		 * so don't do multicast/replicated register read/write
+		 * operation on it.
+		 */
+		if (MEDIA_VER(i915) >= 13 && engine->gt->type == GT_MEDIA)
+			ee->fault_reg = intel_uncore_read(engine->uncore,
+							  XELPMP_RING_FAULT_REG);
+		else if (GRAPHICS_VER_FULL(i915) >= IP_VER(12, 55))
 			ee->fault_reg = intel_gt_mcr_read_any(engine->gt,
 							      XEHP_RING_FAULT_REG);
 		else if (GRAPHICS_VER(i915) >= 12)
@@ -1399,7 +1465,7 @@ static bool record_context(struct i915_gem_context_coredump *e,
 	rcu_read_lock();
 	task = pid_task(ctx->pid, PIDTYPE_PID);
 	if (task) {
-		strcpy(e->comm, task->comm);
+		strscpy(e->comm, task->comm);
 		e->pid = task->pid;
 	}
 	rcu_read_unlock();
@@ -1445,7 +1511,7 @@ capture_vma_snapshot(struct intel_engine_capture_vma *next,
 		return next;
 	}
 
-	strcpy(c->name, name);
+	strscpy(c->name, name);
 	c->vma_res = i915_vma_resource_get(vma_res);
 
 	c->next = next;
@@ -1638,9 +1704,21 @@ capture_engine(struct intel_engine_cs *engine,
 		return NULL;
 
 	intel_engine_get_hung_entity(engine, &ce, &rq);
-	if (rq && !i915_request_started(rq))
-		drm_info(&engine->gt->i915->drm, "Got hung context on %s with active request %lld:%lld [0x%04X] not yet started\n",
-			 engine->name, rq->fence.context, rq->fence.seqno, ce->guc_id.id);
+	if (rq && !i915_request_started(rq)) {
+		/*
+		 * We want to know also what is the guc_id of the context,
+		 * but if we don't have the context reference, then skip
+		 * printing it.
+		 */
+		if (ce)
+			drm_info(&engine->gt->i915->drm,
+				 "Got hung context on %s with active request %lld:%lld [0x%04X] not yet started\n",
+				 engine->name, rq->fence.context, rq->fence.seqno, ce->guc_id.id);
+		else
+			drm_info(&engine->gt->i915->drm,
+				 "Got hung context on %s with active request %lld:%lld not yet started\n",
+				 engine->name, rq->fence.context, rq->fence.seqno);
+	}
 
 	if (rq) {
 		capture = intel_engine_coredump_add_request(ee, rq, ATOMIC_MAYFAIL);
@@ -1713,6 +1791,37 @@ static void gt_record_guc_ctb(struct intel_ctb_coredump *saved,
 	saved->cmds_offset = ((void *)ctb->cmds) - blob_ptr;
 }
 
+static u32 read_guc_state_reg(struct intel_uncore *uncore, int range, int count)
+{
+	GEM_BUG_ON(range >= ARRAY_SIZE(guc_hw_reg_state));
+	GEM_BUG_ON(count >= guc_hw_reg_state[range].count);
+
+	return intel_uncore_read(uncore,
+				 _MMIO(guc_hw_reg_state[range].start + count * sizeof(u32)));
+}
+
+static void gt_record_guc_hw_state(struct intel_uncore *uncore,
+				   struct intel_uc_coredump *error_uc)
+{
+	u32 *hw_state;
+	u32 count = 0;
+	int i, j;
+
+	for (i = 0; i < ARRAY_SIZE(guc_hw_reg_state); i++)
+		count += guc_hw_reg_state[i].count;
+
+	hw_state = kcalloc(count, sizeof(u32), ALLOW_FAIL);
+	if (!hw_state)
+		return;
+
+	count = 0;
+	for (i = 0; i < ARRAY_SIZE(guc_hw_reg_state); i++)
+		for (j = 0; j < guc_hw_reg_state[i].count; j++)
+			hw_state[count++] = read_guc_state_reg(uncore, i, j);
+
+	error_uc->guc.hw_state = hw_state;
+}
+
 static struct intel_uc_coredump *
 gt_record_uc(struct intel_gt_coredump *gt,
 	     struct i915_vma_compress *compress)
@@ -1747,31 +1856,11 @@ gt_record_uc(struct intel_gt_coredump *gt,
 			  uc->guc.ct.ctbs.send.desc, (struct intel_guc *)&uc->guc);
 	gt_record_guc_ctb(error_uc->guc.ctb + 1, &uc->guc.ct.ctbs.recv,
 			  uc->guc.ct.ctbs.send.desc, (struct intel_guc *)&uc->guc);
+	gt_record_guc_hw_state(gt->_gt->uncore, error_uc);
 
 	return error_uc;
 }
 
-/* Capture display registers. */
-static void gt_record_display_regs(struct intel_gt_coredump *gt)
-{
-	struct intel_uncore *uncore = gt->_gt->uncore;
-	struct drm_i915_private *i915 = uncore->i915;
-
-	if (GRAPHICS_VER(i915) >= 6)
-		gt->derrmr = intel_uncore_read(uncore, DERRMR);
-
-	if (GRAPHICS_VER(i915) >= 8)
-		gt->ier = intel_uncore_read(uncore, GEN8_DE_MISC_IER);
-	else if (IS_VALLEYVIEW(i915))
-		gt->ier = intel_uncore_read(uncore, VLV_IER);
-	else if (HAS_PCH_SPLIT(i915))
-		gt->ier = intel_uncore_read(uncore, DEIER);
-	else if (GRAPHICS_VER(i915) == 2)
-		gt->ier = intel_uncore_read16(uncore, GEN2_IER);
-	else
-		gt->ier = intel_uncore_read(uncore, GEN2_IER);
-}
-
 /* Capture all other registers that GuC doesn't capture. */
 static void gt_record_global_nonguc_regs(struct intel_gt_coredump *gt)
 {
@@ -1805,9 +1894,12 @@ static void gt_record_global_nonguc_regs(struct intel_gt_coredump *gt)
 			gt->gtier[i] =
 				intel_uncore_read(uncore, GEN8_GT_IER(i));
 		gt->ngtier = 4;
-	} else if (HAS_PCH_SPLIT(i915)) {
+	} else if (GRAPHICS_VER(i915) >= 5) {
 		gt->gtier[0] = intel_uncore_read(uncore, GTIER);
 		gt->ngtier = 1;
+	} else {
+		gt->gtier[0] = intel_uncore_read(uncore, GEN2_IER);
+		gt->ngtier = 1;
 	}
 
 	gt->eir = intel_uncore_read(uncore, EIR);
@@ -1840,7 +1932,7 @@ static void gt_record_global_regs(struct intel_gt_coredump *gt)
 	if (GRAPHICS_VER(i915) == 7)
 		gt->err_int = intel_uncore_read(uncore, GEN7_ERR_INT);
 
-	if (GRAPHICS_VER_FULL(i915) >= IP_VER(12, 50)) {
+	if (GRAPHICS_VER_FULL(i915) >= IP_VER(12, 55)) {
 		gt->fault_data0 = intel_gt_mcr_read_any((struct intel_gt *)gt->_gt,
 							XEHP_FAULT_TLB_DATA0);
 		gt->fault_data1 = intel_gt_mcr_read_any((struct intel_gt *)gt->_gt,
@@ -1972,7 +2064,7 @@ static void capture_gen(struct i915_gpu_coredump *error)
 	struct drm_i915_private *i915 = error->i915;
 
 	error->wakelock = atomic_read(&i915->runtime_pm.wakeref_count);
-	error->suspended = i915->runtime_pm.suspended;
+	error->suspended = pm_runtime_suspended(i915->drm.dev);
 
 	error->iommu = i915_vtd_active(i915);
 	error->reset_count = i915_reset_count(&i915->gpu_error);
@@ -1985,10 +2077,6 @@ static void capture_gen(struct i915_gpu_coredump *error)
 	memcpy(&error->runtime_info,
 	       RUNTIME_INFO(i915),
 	       sizeof(error->runtime_info));
-	memcpy(&error->display_device_info, DISPLAY_INFO(i915),
-	       sizeof(error->display_device_info));
-	memcpy(&error->display_runtime_info, DISPLAY_RUNTIME_INFO(i915),
-	       sizeof(error->display_runtime_info));
 	error->driver_caps = i915->caps;
 }
 
@@ -2031,7 +2119,6 @@ intel_gt_coredump_alloc(struct intel_gt *gt, gfp_t gfp, u32 dump_flags)
 	gc->_gt = gt;
 	gc->awake = intel_gt_pm_is_awake(gt);
 
-	gt_record_display_regs(gc);
 	gt_record_global_nonguc_regs(gc);
 
 	/*
@@ -2082,6 +2169,7 @@ static struct i915_gpu_coredump *
 __i915_gpu_coredump(struct intel_gt *gt, intel_engine_mask_t engine_mask, u32 dump_flags)
 {
 	struct drm_i915_private *i915 = gt->i915;
+	struct intel_display *display = i915->display;
 	struct i915_gpu_coredump *error;
 
 	/* Check if GPU capture has been disabled */
@@ -2123,12 +2211,12 @@ __i915_gpu_coredump(struct intel_gt *gt, intel_engine_mask_t engine_mask, u32 du
 		error->simulated |= error->gt->simulated;
 	}
 
-	error->overlay = intel_overlay_capture_error_state(i915);
+	error->display_snapshot = intel_display_snapshot_capture(display);
 
 	return error;
 }
 
-struct i915_gpu_coredump *
+static struct i915_gpu_coredump *
 i915_gpu_coredump(struct intel_gt *gt, intel_engine_mask_t engine_mask, u32 dump_flags)
 {
 	static DEFINE_MUTEX(capture_mutex);
@@ -2147,7 +2235,6 @@ i915_gpu_coredump(struct intel_gt *gt, intel_engine_mask_t engine_mask, u32 dump
 void i915_error_state_store(struct i915_gpu_coredump *error)
 {
 	struct drm_i915_private *i915;
-	static bool warned;
 
 	if (IS_ERR_OR_NULL(error))
 		return;
@@ -2161,16 +2248,8 @@ void i915_error_state_store(struct i915_gpu_coredump *error)
 
 	i915_gpu_coredump_get(error);
 
-	if (!xchg(&warned, true) &&
-	    ktime_get_real_seconds() - DRIVER_TIMESTAMP < DAY_AS_SECONDS(180)) {
-		pr_info("GPU hangs can indicate a bug anywhere in the entire gfx stack, including userspace.\n");
-		pr_info("Please file a _new_ bug report at https://gitlab.freedesktop.org/drm/intel/issues/new.\n");
-		pr_info("Please see https://gitlab.freedesktop.org/drm/intel/-/wikis/How-to-file-i915-bugs for details.\n");
-		pr_info("drm/i915 developers can then reassign to the right component if it's not a kernel issue.\n");
-		pr_info("The GPU crash dump is required to analyze GPU hangs, so please always attach it.\n");
-		pr_info("GPU crash dump saved to /sys/class/drm/card%d/error\n",
-			i915->drm.primary->index);
-	}
+	drm_info(&i915->drm, "GPU error state saved to /sys/class/drm/card%d/error\n",
+		 i915->drm.primary->index);
 }
 
 /**
@@ -2199,7 +2278,7 @@ void i915_capture_error_state(struct intel_gt *gt,
 	i915_gpu_coredump_put(error);
 }
 
-struct i915_gpu_coredump *
+static struct i915_gpu_coredump *
 i915_first_error_state(struct drm_i915_private *i915)
 {
 	struct i915_gpu_coredump *error;
@@ -2366,3 +2445,184 @@ void intel_klog_error_capture(struct intel_gt *gt,
 	drm_info(&i915->drm, "[Capture/%d.%d] Dumped %zd bytes\n", l_count, line++, pos_err);
 }
 #endif
+
+static ssize_t gpu_state_read(struct file *file, char __user *ubuf,
+			      size_t count, loff_t *pos)
+{
+	struct i915_gpu_coredump *error;
+	ssize_t ret;
+	void *buf;
+
+	error = file->private_data;
+	if (!error)
+		return 0;
+
+	/* Bounce buffer required because of kernfs __user API convenience. */
+	buf = kmalloc(count, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	ret = i915_gpu_coredump_copy_to_buffer(error, buf, *pos, count);
+	if (ret <= 0)
+		goto out;
+
+	if (!copy_to_user(ubuf, buf, ret))
+		*pos += ret;
+	else
+		ret = -EFAULT;
+
+out:
+	kfree(buf);
+	return ret;
+}
+
+static int gpu_state_release(struct inode *inode, struct file *file)
+{
+	i915_gpu_coredump_put(file->private_data);
+	return 0;
+}
+
+static int i915_gpu_info_open(struct inode *inode, struct file *file)
+{
+	struct drm_i915_private *i915 = inode->i_private;
+	struct i915_gpu_coredump *gpu;
+	intel_wakeref_t wakeref;
+
+	gpu = NULL;
+	with_intel_runtime_pm(&i915->runtime_pm, wakeref)
+		gpu = i915_gpu_coredump(to_gt(i915), ALL_ENGINES, CORE_DUMP_FLAG_NONE);
+
+	if (IS_ERR(gpu))
+		return PTR_ERR(gpu);
+
+	file->private_data = gpu;
+	return 0;
+}
+
+static const struct file_operations i915_gpu_info_fops = {
+	.owner = THIS_MODULE,
+	.open = i915_gpu_info_open,
+	.read = gpu_state_read,
+	.llseek = default_llseek,
+	.release = gpu_state_release,
+};
+
+static ssize_t
+i915_error_state_write(struct file *filp,
+		       const char __user *ubuf,
+		       size_t cnt,
+		       loff_t *ppos)
+{
+	struct i915_gpu_coredump *error = filp->private_data;
+
+	if (!error)
+		return 0;
+
+	drm_dbg(&error->i915->drm, "Resetting error state\n");
+	i915_reset_error_state(error->i915);
+
+	return cnt;
+}
+
+static int i915_error_state_open(struct inode *inode, struct file *file)
+{
+	struct i915_gpu_coredump *error;
+
+	error = i915_first_error_state(inode->i_private);
+	if (IS_ERR(error))
+		return PTR_ERR(error);
+
+	file->private_data  = error;
+	return 0;
+}
+
+static const struct file_operations i915_error_state_fops = {
+	.owner = THIS_MODULE,
+	.open = i915_error_state_open,
+	.read = gpu_state_read,
+	.write = i915_error_state_write,
+	.llseek = default_llseek,
+	.release = gpu_state_release,
+};
+
+void i915_gpu_error_debugfs_register(struct drm_i915_private *i915)
+{
+	struct dentry *debugfs_root = i915->drm.debugfs_root;
+
+	debugfs_create_file("i915_error_state", 0644, debugfs_root, i915,
+			    &i915_error_state_fops);
+	debugfs_create_file("i915_gpu_info", 0644, debugfs_root, i915,
+			    &i915_gpu_info_fops);
+}
+
+static ssize_t error_state_read(struct file *filp, struct kobject *kobj,
+				const struct bin_attribute *attr, char *buf,
+				loff_t off, size_t count)
+{
+
+	struct device *kdev = kobj_to_dev(kobj);
+	struct drm_i915_private *i915 = kdev_minor_to_i915(kdev);
+	struct i915_gpu_coredump *gpu;
+	ssize_t ret = 0;
+
+	/*
+	 * FIXME: Concurrent clients triggering resets and reading + clearing
+	 * dumps can cause inconsistent sysfs reads when a user calls in with a
+	 * non-zero offset to complete a prior partial read but the
+	 * gpu_coredump has been cleared or replaced.
+	 */
+
+	gpu = i915_first_error_state(i915);
+	if (IS_ERR(gpu)) {
+		ret = PTR_ERR(gpu);
+	} else if (gpu) {
+		ret = i915_gpu_coredump_copy_to_buffer(gpu, buf, off, count);
+		i915_gpu_coredump_put(gpu);
+	} else {
+		const char *str = "No error state collected\n";
+		size_t len = strlen(str);
+
+		if (off < len) {
+			ret = min_t(size_t, count, len - off);
+			memcpy(buf, str + off, ret);
+		}
+	}
+
+	return ret;
+}
+
+static ssize_t error_state_write(struct file *file, struct kobject *kobj,
+				 const struct bin_attribute *attr, char *buf,
+				 loff_t off, size_t count)
+{
+	struct device *kdev = kobj_to_dev(kobj);
+	struct drm_i915_private *dev_priv = kdev_minor_to_i915(kdev);
+
+	drm_dbg(&dev_priv->drm, "Resetting error state\n");
+	i915_reset_error_state(dev_priv);
+
+	return count;
+}
+
+static const struct bin_attribute error_state_attr = {
+	.attr.name = "error",
+	.attr.mode = S_IRUSR | S_IWUSR,
+	.size = 0,
+	.read = error_state_read,
+	.write = error_state_write,
+};
+
+void i915_gpu_error_sysfs_setup(struct drm_i915_private *i915)
+{
+	struct device *kdev = i915->drm.primary->kdev;
+
+	if (sysfs_create_bin_file(&kdev->kobj, &error_state_attr))
+		drm_err(&i915->drm, "error_state sysfs setup failed\n");
+}
+
+void i915_gpu_error_sysfs_teardown(struct drm_i915_private *i915)
+{
+	struct device *kdev = i915->drm.primary->kdev;
+
+	sysfs_remove_bin_file(&kdev->kobj, &error_state_attr);
+}