[Intel-xe] [PATCH] drm/xe: Use max wopcm size when validating the preset GuC wopcm size

[Balasubramani Vivekanandan]

When the GuC wopcm base and size registers are populated by BIOS/IFWI,
validate the parameters against the maximum allowed wopcm size.

Bpsec: 44982

Signed-off-by: Balasubramani Vivekanandan <balasubramani.vivekanandan at intel.com>
---
 drivers/gpu/drm/xe/xe_wopcm.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/gpu/drm/xe/xe_wopcm.c b/drivers/gpu/drm/xe/xe_wopcm.c
index 0f2485d9d9af..d55469e941bf 100644
--- a/drivers/gpu/drm/xe/xe_wopcm.c
+++ b/drivers/gpu/drm/xe/xe_wopcm.c
@@ -54,6 +54,8 @@
 						   for MTL, do a proper probe
 						   sooner or later */
 #define GEN11_WOPCM_SIZE		SZ_2M
+
+#define GEN12_MAX_WOPCM_SIZE            SZ_8M
 /* 16KB WOPCM (RSVD WOPCM) is reserved from HuC firmware top. */
 #define WOPCM_RESERVED_SIZE		SZ_16K
 
@@ -226,6 +228,13 @@ int xe_wopcm_init(struct xe_wopcm *wopcm)
 	if (locked) {
 		drm_dbg(&xe->drm, "GuC WOPCM is already locked [%uK, %uK)\n",
 			guc_wopcm_base / SZ_1K, guc_wopcm_size / SZ_1K);
+		/*
+		 * When the GuC wopcm base and size are preprogrammed by
+		 * BIOS/IFWI, check against the max allowed wopcm size to
+		 * validate if the programmed values align to the wopcm layout.
+		 */
+		wopcm->size = GEN12_MAX_WOPCM_SIZE;
+
 		goto check;
 	}
 
-- 
2.34.1