Add software error classification support and reuse the
common CPER header initialization path.

Populate software error metadata without emitting a CPER
record yet.

Cc: Badal Nilawar <badal.nilawar@intel.com>
Signed-off-by: Mallesh Koujalagi <mallesh.koujalagi@intel.com>
---
v2:
- Move union inside xe_cper_intel_hdr structure. (Badal)

v3:
- Introduce structure where it's used. (Badal)
- Move error-class union inside cper_init_intel_hdr. (Badal)
---
 drivers/gpu/drm/xe/xe_cper.c       | 21 +++++++++++++++++---
 drivers/gpu/drm/xe/xe_cper_types.h | 32 ++++++++++++++++++++++++++++--
 2 files changed, 48 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/xe/xe_cper.c b/drivers/gpu/drm/xe/xe_cper.c
index db3513c59834..10aa10bbf282 100644
--- a/drivers/gpu/drm/xe/xe_cper.c
+++ b/drivers/gpu/drm/xe/xe_cper.c
@@ -14,6 +14,8 @@
 #include <linux/time.h>
 #include <linux/timekeeping.h>
 
+#include "abi/xe_log_abi.h"
+
 #include "xe_cper.h"
 #include "xe_cper_types.h"
 #include "xe_device.h"
@@ -92,11 +94,11 @@ static u64 cper_timestamp_now(void)
 	return ts;
 }
 
-static void cper_init_intel_hdr(struct xe_device *xe, const struct xe_ras_error_class *counter,
+static void cper_init_intel_hdr(struct xe_device *xe, const union xe_cper_error_class *error_class,
 				u64 first_timestamp, u32 sig_id, u32 error_count,
 				struct xe_cper_intel_hdr *ihdr)
 {
-	ihdr->counter = *counter;
+	ihdr->error_class = *error_class;
 	ihdr->validation_bits |= XE_CPER_VALID_LOCATION;
 	ihdr->sig_id = U32_MAX;
 
@@ -219,11 +221,12 @@ void xe_cper_emit_counter(struct xe_device *xe, int cper_sev, enum xe_sigid sigi
 			  const struct xe_ras_error_class *counter,
 			  const struct xe_ras_get_counter_response *response)
 {
+	union xe_cper_error_class error_class = { .counter = *counter };
 	struct xe_cper_intel_hdr ihdr = {};
 
 	xe_assert(xe, is_hw_sigid(sigid));
 
-	cper_init_intel_hdr(xe, counter, response->timestamp,
+	cper_init_intel_hdr(xe, &error_class, response->timestamp,
 			    sigid, response->value, &ihdr);
 	cper_record_emit(xe, cper_sev, &INTEL_CPER_NOTIFY_GPU_ERROR, &ihdr, NULL, 0);
 }
@@ -249,6 +252,18 @@ static void cper_emit_sw_err(struct xe_device *xe, int cper_sev, enum xe_sigid s
 			     u32 component, u32 location, const void *data,
 			     struct va_format *vaf)
 {
+	union xe_cper_error_class error_class = {};
+	struct xe_cper_intel_hdr ihdr = {};
+	struct xe_cper_driver_error_class *driver = &error_class.driver;
+	u64 timestamp = ktime_get_boottime_ns();

Why not ktime_get_real_ns? Also, for readability, initialize it later.

+
+	driver->error_type = cper_sev;
+	driver->error_component = component;
+	driver->tile = location;
+	if (IS_ERR(data))
+		driver->cause = -PTR_ERR(data);
+
+	cper_init_intel_hdr(xe, &error_class, timestamp, sigid, 1, &ihdr);
 }
 
 /**
diff --git a/drivers/gpu/drm/xe/xe_cper_types.h b/drivers/gpu/drm/xe/xe_cper_types.h
index 68e30df0440e..d8581992dc45 100644
--- a/drivers/gpu/drm/xe/xe_cper_types.h
+++ b/drivers/gpu/drm/xe/xe_cper_types.h
@@ -45,6 +45,29 @@
 	GUID_INIT(0xea9d8f84, 0x4258, 0x5227, \
 		  0x80, 0x28, 0xb9, 0xb1, 0x3e, 0x6d, 0x58, 0xb0)
 
+/**
+ * struct xe_cper_driver_error_class - Intel GPU CPER driver-detected error classification
+ */
+struct xe_cper_driver_error_class {
+	/** @error_type: CPER severity: CPER_SEV_* */
+	u8  error_type;
+	/** @reserved0: Reserved, must be zero */
+	u8  reserved0;
+	/** @error_component: Driver component id: CLASS[7:0].TYPE[15:8] */
+	u16 error_component;
+	/** @tile: Driver location id: TYPE[7:0].ID[15:8] ('tile' and 'GT' field region) */
+	u16 tile;
+	/** @reserved1: Reserved, must be zero */
+	u16 reserved1;
+	/** @cause: errno of the failing operation, or 0 if none */
+	u32 cause;
+};
+
+/* Same size as the counter-sourced error_class */
+#define XE_CPER_ERROR_CLASS_SIZE	12
+
+static_assert(sizeof(struct xe_cper_driver_error_class) == XE_CPER_ERROR_CLASS_SIZE);
+
 /**
  * struct xe_cper_intel_hdr - Intel-specific CPER header
  *
@@ -52,8 +75,13 @@
  * All multi-byte fields are little-endian.
  */
 struct xe_cper_intel_hdr {
-	/** @counter: Error class (severity, component, location, cause) */
-	struct xe_ras_error_class counter;
+	/** @error_class: Counter-sourced or driver-detected error classification */

+	union xe_cper_error_class {
+		/** @error_class.counter: Counter-sourced error classification */

Keep the original doc.

Thanks,
Badal

+		struct xe_ras_error_class counter;
+		/** @error_class.driver: Driver-detected error classification */
+		struct xe_cper_driver_error_class driver;
+	} error_class;
 	/** @first_timestamp: First occurrence of this error class, in ticks */
 	u64 first_timestamp;
 	/** @sig_id: Aggregated error class SIG ID; set to U32_MAX if unknown */