drm/xe/guc: Fix capture of steering registers

The list of registers to capture on a GPU hang includes some that
require steering. Unfortunately, the flag to say this was being wiped
to due a missing OR on the assignment of the next flag field.

Fix that.

Fixes: b170d69 ("drm/xe/guc: Add XE_LP steered register lists")
Cc: Zhanjun Dong <[email protected]>
Cc: Alan Previn <[email protected]>
Cc: Matt Roper <[email protected]>
Cc: Lucas De Marchi <[email protected]>
Cc: "Thomas Hellström" <[email protected]>
Cc: Rodrigo Vivi <[email protected]>
Cc: [email protected]
Signed-off-by: John Harrison <[email protected]>
Reviewed-by: Matt Roper <[email protected]>
Reviewed-by: Zhanjun Dong <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
(cherry picked from commit 532da44)
Signed-off-by: Lucas De Marchi <[email protected]>

Author: johnharr-intel

drivers/gpu/drm/xe/xe_guc_capture.c

@@ -359,7 +359,7 @@ static void __fill_ext_reg(struct __guc_mmio_reg_descr *ext,
 
 	ext->reg = XE_REG(extlist->reg.__reg.addr);
 	ext->flags = FIELD_PREP(GUC_REGSET_STEERING_NEEDED, 1);
-	ext->flags = FIELD_PREP(GUC_REGSET_STEERING_GROUP, slice_id);
+	ext->flags |= FIELD_PREP(GUC_REGSET_STEERING_GROUP, slice_id);
 	ext->flags |= FIELD_PREP(GUC_REGSET_STEERING_INSTANCE, subslice_id);
 	ext->regname = extlist->name;
 }