[RFC 2/7] drm/i915/pxp: Refactor mei-teelink checks at init/fini

[Alan Previn <alan.previn.teres.alexis@xxxxxxxxx>]

In preparation of MTL-pxp support, add helper functions to
determine if teelink is required and to determine the type
of teelink for the current gt-pxp subsystem.

Signed-off-by: Alan Previn <alan.previn.teres.alexis@xxxxxxxxx>
---
 drivers/gpu/drm/i915/pxp/intel_pxp.c     |  6 +++---
 drivers/gpu/drm/i915/pxp/intel_pxp_tee.c | 26 ++++++++++++++++++++++++
 drivers/gpu/drm/i915/pxp/intel_pxp_tee.h |  3 +++
 3 files changed, 32 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp.c b/drivers/gpu/drm/i915/pxp/intel_pxp.c
index 58219beecfa4..33f86bb05148 100644
--- a/drivers/gpu/drm/i915/pxp/intel_pxp.c
+++ b/drivers/gpu/drm/i915/pxp/intel_pxp.c
@@ -174,7 +174,7 @@ static void pxp_init_full(struct intel_pxp *pxp)
 	if (ret)
 		return;
 
-	ret = intel_pxp_tee_component_init(pxp);
+	ret = intel_pxp_teelink_init(pxp);
 	if (ret)
 		goto out_context;
 
@@ -197,14 +197,14 @@ void intel_pxp_init(struct intel_pxp *pxp)
 	if (intel_pxp_supported_on_gt(pxp))
 		pxp_init_full(pxp);
 	else if (_gt_needs_teelink(gt))
-		intel_pxp_tee_component_init(pxp);
+		intel_pxp_teelink_init(pxp);
 }
 
 void intel_pxp_fini(struct intel_pxp *pxp)
 {
 	pxp->arb_is_valid = false;
 
-	intel_pxp_tee_component_fini(pxp);
+	intel_pxp_teelink_fini(pxp);
 
 	destroy_vcs_context(pxp);
 }
diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp_tee.c b/drivers/gpu/drm/i915/pxp/intel_pxp_tee.c
index b9198e961cb6..23a848b52c75 100644
--- a/drivers/gpu/drm/i915/pxp/intel_pxp_tee.c
+++ b/drivers/gpu/drm/i915/pxp/intel_pxp_tee.c
@@ -319,3 +319,29 @@ int intel_pxp_tee_cmd_create_arb_session(struct intel_pxp *pxp,
 
 	return ret;
 }
+
+static bool gt_supports_teelink_via_mei(struct intel_gt *gt)
+{
+	return (IS_ENABLED(CONFIG_INTEL_MEI_PXP) && !HAS_ENGINE(gt, GSC0));
+}
+
+int intel_pxp_teelink_init(struct intel_pxp *pxp)
+{
+	struct intel_gt *gt = pxp_to_gt(pxp);
+	int ret = -ENOLINK;
+
+	if (!gt_supports_teelink_via_mei(gt))
+		return -ENODEV;
+
+	ret = intel_pxp_tee_component_init(pxp);
+	if (ret)
+		drm_warn(&gt->i915->drm, "Teelink initialization failed with %d\n", ret);
+
+	return ret;
+}
+
+void intel_pxp_teelink_fini(struct intel_pxp *pxp)
+{
+	intel_pxp_tee_component_fini(pxp);
+}
+
diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp_tee.h b/drivers/gpu/drm/i915/pxp/intel_pxp_tee.h
index aeb3dfe7ce96..62995e95773f 100644
--- a/drivers/gpu/drm/i915/pxp/intel_pxp_tee.h
+++ b/drivers/gpu/drm/i915/pxp/intel_pxp_tee.h
@@ -19,4 +19,7 @@ int intel_pxp_tee_stream_message(struct intel_pxp *pxp,
 				 void *msg_in, size_t msg_in_len,
 				 void *msg_out, size_t msg_out_len);
 
+int intel_pxp_teelink_init(struct intel_pxp *pxp);
+void intel_pxp_teelink_fini(struct intel_pxp *pxp);
+
 #endif /* __INTEL_PXP_TEE_H__ */
-- 
2.34.1