[PATCH v4 2/3] drm/xe/xe_drm_ras: Add error-event support for PVC

[Riana Tauro <riana.tauro@intel.com>]

Report drm_ras error event to userspace when an error occurs.
Add support for core-compute and SoC errors in PVC.

$ sudo ynl --family drm_ras --output-json --subscribe error-report

{
    "name": "error-event",
     "msg": {
         "device-name": "0000:03:00.0",
         "node-id": 1,
         "node-name": "uncorrectable-errors",
         "error-id": 1,
         "error-name": "core-compute",
         "error-value": 1
     }
}

Signed-off-by: Riana Tauro <riana.tauro@intel.com>
Reviewed-by: Raag Jadav <raag.jadav@intel.com>
---
v2: use ynl (Raag)
    use value as function parameter
    move error event call to hw_error_source_handler 

v3: add has_drm_ras check

v4: use drm_err_ratelimited
    initialize node post drm_ras check (Sashiko)
---
 drivers/gpu/drm/xe/xe_drm_ras.c  | 32 ++++++++++++++++++++++++++++++++
 drivers/gpu/drm/xe/xe_drm_ras.h  |  3 +++
 drivers/gpu/drm/xe/xe_hw_error.c |  5 ++++-
 3 files changed, 39 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/xe/xe_drm_ras.c b/drivers/gpu/drm/xe/xe_drm_ras.c
index 7937d8ba0ed9..8e247a8139b1 100644
--- a/drivers/gpu/drm/xe/xe_drm_ras.c
+++ b/drivers/gpu/drm/xe/xe_drm_ras.c
@@ -185,6 +185,38 @@ static int register_nodes(struct xe_device *xe)
 	return ret;
 }
 
+/**
+ * xe_drm_ras_event() - Report drm_ras error event to userspace
+ * @xe: xe device structure
+ * @component: error component (see &enum drm_xe_ras_error_component)
+ * @severity: error severity (see &enum drm_xe_ras_error_severity)
+ * @value: value of error counter
+ * @flags: flags for allocation
+ *
+ * Report an error-event to userspace.
+ */
+void xe_drm_ras_event(struct xe_device *xe, u32 component, u32 severity, u32 value, gfp_t flags)
+{
+	struct xe_drm_ras *ras = &xe->ras;
+	struct xe_drm_ras_counter *info = ras->info[severity];
+	struct drm_ras_node *node;
+	int ret;
+
+	/* Event is supported only if drm_ras is enabled */
+	if (!xe->info.has_drm_ras)
+		return;
+
+	node = &ras->node[severity];
+
+	if (!info || !info[component].name)
+		return;
+
+	ret = drm_ras_nl_error_event(node, component, info[component].name, value, flags);
+	if (ret)
+		drm_err_ratelimited(&xe->drm, "drm_ras error-event failed: %d for %s %s\n", ret,
+				    info[component].name, error_severity[severity]);
+}
+
 /**
  * xe_drm_ras_init() - Initialize DRM RAS
  * @xe: xe device instance
diff --git a/drivers/gpu/drm/xe/xe_drm_ras.h b/drivers/gpu/drm/xe/xe_drm_ras.h
index 365c70e93e82..2a694bf69478 100644
--- a/drivers/gpu/drm/xe/xe_drm_ras.h
+++ b/drivers/gpu/drm/xe/xe_drm_ras.h
@@ -5,11 +5,14 @@
 #ifndef _XE_DRM_RAS_H_
 #define _XE_DRM_RAS_H_
 
+#include <linux/types.h>
+
 struct xe_device;
 
 #define for_each_error_severity(i)	\
 	for (i = 0; i < DRM_XE_RAS_ERR_SEV_MAX; i++)
 
 int xe_drm_ras_init(struct xe_device *xe);
+void xe_drm_ras_event(struct xe_device *xe, u32 component, u32 severity, u32 value, gfp_t flags);
 
 #endif
diff --git a/drivers/gpu/drm/xe/xe_hw_error.c b/drivers/gpu/drm/xe/xe_hw_error.c
index 4a4b363fc844..a833cecc74ec 100644
--- a/drivers/gpu/drm/xe/xe_hw_error.c
+++ b/drivers/gpu/drm/xe/xe_hw_error.c
@@ -432,7 +432,7 @@ static void hw_error_source_handler(struct xe_tile *tile, const enum hardware_er
 	struct xe_drm_ras *ras = &xe->ras;
 	struct xe_drm_ras_counter *info = ras->info[severity];
 	unsigned long flags, err_src;
-	u32 err_bit;
+	u32 err_bit, value;
 
 	if (!IS_DGFX(xe))
 		return;
@@ -495,6 +495,9 @@ static void hw_error_source_handler(struct xe_tile *tile, const enum hardware_er
 			gt_hw_error_handler(tile, hw_err, error_id);
 		if (err_bit == XE_SOC_ERROR)
 			soc_hw_error_handler(tile, hw_err, error_id);
+
+		value = atomic_read(&info[error_id].counter);
+		xe_drm_ras_event(xe, error_id, severity, value, GFP_ATOMIC);
 	}
 
 clear_reg:
-- 
2.47.1