[Intel-gfx] [PATCH 3/3] [v2] drm/i915: Make i915 events part of uapi

[Ben Widawsky]

Make the uevent strings part of the user API for people who wish to
write their own listeners.

v2: Make a space in the string concatenation. (Chad)
Use the "UEVENT" suffix intead of "EVENT" (Chad)
Make kernel-doc (Daniel)

Thanks to Daniel Vetter for a majority of the parity error comments.

CC: Chad Versace <chad.versace at linux.intel.com>
Signed-off-by: Ben Widawsky <ben at bwidawsk.net>
---
 drivers/gpu/drm/i915/i915_irq.c |  8 ++++----
 include/uapi/drm/i915_drm.h     | 22 ++++++++++++++++++++++
 2 files changed, 26 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index 03071d7..3e19ce0 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -812,7 +812,7 @@ static void ivybridge_parity_work(struct work_struct *work)
 
 	mutex_unlock(&dev_priv->dev->struct_mutex);
 
-	parity_event[0] = "L3_PARITY_ERROR=1";
+	parity_event[0] = I915_L3_PARITY_UEVENT "=1";
 	parity_event[1] = kasprintf(GFP_KERNEL, "ROW=%d", row);
 	parity_event[2] = kasprintf(GFP_KERNEL, "BANK=%d", bank);
 	parity_event[3] = kasprintf(GFP_KERNEL, "SUBBANK=%d", subbank);
@@ -1435,8 +1435,8 @@ static void i915_error_work_func(struct work_struct *work)
 						    gpu_error);
 	struct drm_device *dev = dev_priv->dev;
 	struct intel_ring_buffer *ring;
-	char *reset_event[] = { "RESET=1", NULL };
-	char *reset_done_event[] = { "RESET=0", NULL };
+	char *reset_event[] = { I915_RESET_UEVENT "=1", NULL };
+	char *reset_done_event[] = { I915_RESET_UEVENT "=0", NULL };
 	int i, ret;
 
 	/*
@@ -1591,7 +1591,7 @@ void i915_handle_error(struct drm_device *dev, bool wedged)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	struct intel_ring_buffer *ring;
-	char *error_event[] = { "ERROR=1", NULL };
+	char *error_event[] = { I915_ERROR_UEVENT "=1", NULL };
 	int i;
 
 	i915_capture_error_state(dev);
diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h
index 923ed7f..f5fe31b 100644
--- a/include/uapi/drm/i915_drm.h
+++ b/include/uapi/drm/i915_drm.h
@@ -33,6 +33,28 @@
  * subject to backwards-compatibility constraints.
  */
 
+/**
+ * DOC: uevents generated by i915 on it's device node
+ *
+ * I915_L3_PARITY_UEVENT - Generated when the driver receives a parity mismatch
+ *	event from the gpu l3 cache. Additional information supplied is ROW,
+ *	BANK, SUBBANK of the affected cacheline. Userspace should keep track of
+ *	these events and if a specific cache-line seems to have a persistent
+ *	error remap it with the l3 remapping tool supplied in intel-gpu-tools.
+ *	The value supplied with the event is always 1.
+ *
+ * I915_ERROR_UEVENT - Generated upon error detection, currently only via
+ *	hangcheck. The error detection event is a good indicator of when things
+ *	began to go badly. The value supplied with the event is always 1.
+ *
+ * I915_RESET_UEVENT - Event is generated just before an attempt to reset the
+ *	the GPU. Reset has historically been a precarious attempt which the GPU
+ *	may or may not recover from. The value supplied with the event is 1
+ *	before the reset attempt, and a 0 after it has completed.
+ */
+#define I915_L3_PARITY_UEVENT "L3_PARITY_ERROR"
+#define I915_ERROR_UEVENT "ERROR"
+#define I915_RESET_UEVENT "RESET"
 
 /* Each region is a minimum of 16k, and there are at most 255 of them.
  */
-- 
1.8.3.3