drm/i915/pxp: Add GSC-CS back-end resource init and cleanup

For MTL, the PXP back-end transport uses the GSC engine to submit
HECI packets through the HW to the GSC firmware for PXP arb
session management. This submission uses a non-priveleged
batch buffer, a buffer for the command packet and of course
a context targeting the GSC-CS.

Thus for MTL, we need to allocate and free a set of execution
submission resources for the management of the arbitration session.
Lets start with the context creation first since that object and
its usage is very straight-forward. We'll add the buffer allocation
and freeing later when we introduce the gsccs' send-message function.

Do this one time allocation of gsccs specific resources in
a new gsccs source file with intel_pxp_gsccs_init / fini functions
and hook them up from the PXP front-end.

Signed-off-by: Alan Previn <alan.previn.teres.alexis@intel.com>
Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: Radhakrishna Sripada <radhakrishna.sripada@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230511231738.1077674-2-alan.previn.teres.alexis@intel.com

1 files changed, 29 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp_gsccs.h b/drivers/gpu/drm/i915/pxp/intel_pxp_gsccs.h
new file mode 100644
index 000000000000..354ea9a8f940
--- /dev/null
+++ b/drivers/gpu/drm/i915/pxp/intel_pxp_gsccs.h
@@ -0,0 +1,29 @@
+/* SPDX-License-Identifier: MIT */
+/*
+ * Copyright(c) 2022, Intel Corporation. All rights reserved.
+ */
+
+#ifndef __INTEL_PXP_GSCCS_H__
+#define __INTEL_PXP_GSCCS_H__
+
+#include <linux/types.h>
+
+struct intel_pxp;
+
+#ifdef CONFIG_DRM_I915_PXP
+void intel_pxp_gsccs_fini(struct intel_pxp *pxp);
+int intel_pxp_gsccs_init(struct intel_pxp *pxp);
+
+#else
+static inline void intel_pxp_gsccs_fini(struct intel_pxp *pxp)
+{
+}
+
+static inline int intel_pxp_gsccs_init(struct intel_pxp *pxp)
+{
+	return 0;
+}
+
+#endif
+
+#endif /*__INTEL_PXP_GSCCS_H__ */