drm/xe/gsc: Define GSC FW for MTL

We track GSC FW based on its compatibility version, which is what
determines the interface it supports.
Also add a modparam override like the ones for GuC and HuC.

v2: fix module param description (John)
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Alan Previn <alan.previn.teres.alexis@intel.com>
Cc: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: John Harrison <John.C.Harrison@Intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

drivers/gpu/drm/xe/xe_module.c

@@ -41,6 +41,10 @@ module_param_named_unsafe(huc_firmware_path, xe_modparam.huc_firmware_path, char
 MODULE_PARM_DESC(huc_firmware_path,
 		 "HuC firmware path to use instead of the default one - empty string disables");
 
+module_param_named_unsafe(gsc_firmware_path, xe_modparam.gsc_firmware_path, charp, 0400);
+MODULE_PARM_DESC(gsc_firmware_path,
+		 "GSC firmware path to use instead of the default one - empty string disables");
+
 module_param_named_unsafe(force_probe, xe_modparam.force_probe, charp, 0400);
 MODULE_PARM_DESC(force_probe,
 		 "Force probe options for specified devices. See CONFIG_DRM_XE_FORCE_PROBE for details.");

drivers/gpu/drm/xe/xe_module.h

@@ -16,6 +16,7 @@ struct xe_modparam {
 	int guc_log_level;
 	char *guc_firmware_path;
 	char *huc_firmware_path;
+	char *gsc_firmware_path;
 	char *force_probe;
 };
 

drivers/gpu/drm/xe/xe_uc_fw.c

@@ -121,6 +121,10 @@ struct fw_blobs_by_type {
 	fw_def(ROCKETLAKE,	no_ver(i915,	huc,		tgl))		\
 	fw_def(TIGERLAKE,	no_ver(i915,	huc,		tgl))
 
+/* for the GSC FW we match the compatibility version and not the release one */
+#define XE_GSC_FIRMWARE_DEFS(fw_def, major_ver)		\
+	fw_def(METEORLAKE,	major_ver(i915,	gsc,	mtl,	1, 0))
+
 #define MAKE_FW_PATH(dir__, uc__, shortname__, version__)			\
 	__stringify(dir__) "/" __stringify(shortname__) "_" __stringify(uc__) version__ ".bin"
 
@@ -155,6 +159,7 @@ XE_GUC_FIRMWARE_DEFS(XE_UC_MODULE_FIRMWARE,
 		     fw_filename_mmp_ver, fw_filename_major_ver)
 XE_HUC_FIRMWARE_DEFS(XE_UC_MODULE_FIRMWARE,
 		     fw_filename_mmp_ver, fw_filename_no_ver)
+XE_GSC_FIRMWARE_DEFS(XE_UC_MODULE_FIRMWARE, fw_filename_major_ver)
 
 static struct xe_gt *
 __uc_fw_to_gt(struct xe_uc_fw *uc_fw, enum xe_uc_fw_type type)
@@ -196,23 +201,19 @@ uc_fw_auto_select(struct xe_device *xe, struct xe_uc_fw *uc_fw)
 				     uc_fw_entry_mmp_ver,
 				     uc_fw_entry_no_ver)
 	};
+	static const struct uc_fw_entry entries_gsc[] = {
+		XE_GSC_FIRMWARE_DEFS(XE_UC_FW_ENTRY, uc_fw_entry_major_ver)
+	};
 	static const struct fw_blobs_by_type blobs_all[XE_UC_FW_NUM_TYPES] = {
 		[XE_UC_FW_TYPE_GUC] = { entries_guc, ARRAY_SIZE(entries_guc) },
 		[XE_UC_FW_TYPE_HUC] = { entries_huc, ARRAY_SIZE(entries_huc) },
+		[XE_UC_FW_TYPE_GSC] = { entries_gsc, ARRAY_SIZE(entries_gsc) },
 	};
 	static const struct uc_fw_entry *entries;
 	enum xe_platform p = xe->info.platform;
 	u32 count;
 	int i;
 
-	/*
-	 * GSC FW support is still not fully in place, so we're not defining
-	 * the FW blob yet because we don't want the driver to attempt to load
-	 * it until we're ready for it.
-	 */
-	if (uc_fw->type == XE_UC_FW_TYPE_GSC)
-		return;
-
 	xe_assert(xe, uc_fw->type < ARRAY_SIZE(blobs_all));
 	entries = blobs_all[uc_fw->type].entries;
 	count = blobs_all[uc_fw->type].count;
@@ -248,6 +249,9 @@ uc_fw_override(struct xe_uc_fw *uc_fw)
 	case XE_UC_FW_TYPE_HUC:
 		path_override = xe_modparam.huc_firmware_path;
 		break;
+	case XE_UC_FW_TYPE_GSC:
+		path_override = xe_modparam.gsc_firmware_path;
+		break;
 	default:
 		break;
 	}