diff --git a/drivers/gpu/drm/i915/gt/uc/intel_gsc_fw.c b/drivers/gpu/drm/i915/gt/uc/intel_gsc_fw.c
index 236673c02f9a..013dfe284a28 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_gsc_fw.c
+++ b/drivers/gpu/drm/i915/gt/uc/intel_gsc_fw.c
@@ -13,6 +13,7 @@
 #define GSC_FW_STATUS_REG			_MMIO(0x116C40)
 #define GSC_FW_CURRENT_STATE			REG_GENMASK(3, 0)
 #define   GSC_FW_CURRENT_STATE_RESET		0
+#define   GSC_FW_PROXY_STATE_NORMAL		5
 #define GSC_FW_INIT_COMPLETE_BIT		REG_BIT(9)
 
 static bool gsc_is_in_reset(struct intel_uncore *uncore)
@@ -31,6 +32,15 @@ bool intel_gsc_uc_fw_init_done(struct intel_gsc_uc *gsc)
 	return fw_status & GSC_FW_INIT_COMPLETE_BIT;
 }
 
+bool intel_gsc_uc_fw_proxy_init_done(struct intel_gsc_uc *gsc)
+{
+	struct intel_uncore *uncore = gsc_uc_to_gt(gsc)->uncore;
+	u32 fw_status = intel_uncore_read(uncore, GSC_FW_STATUS_REG);
+
+	return REG_FIELD_GET(GSC_FW_CURRENT_STATE, fw_status) ==
+	       GSC_FW_PROXY_STATE_NORMAL;
+}
+
 static int emit_gsc_fw_load(struct i915_request *rq, struct intel_gsc_uc *gsc)
 {
 	u32 offset = i915_ggtt_offset(gsc->local);
diff --git a/drivers/gpu/drm/i915/gt/uc/intel_gsc_fw.h b/drivers/gpu/drm/i915/gt/uc/intel_gsc_fw.h
index f4c1106bb2a9..fff8928218df 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_gsc_fw.h
+++ b/drivers/gpu/drm/i915/gt/uc/intel_gsc_fw.h
@@ -13,5 +13,6 @@ struct intel_uncore;
 
 int intel_gsc_uc_fw_upload(struct intel_gsc_uc *gsc);
 bool intel_gsc_uc_fw_init_done(struct intel_gsc_uc *gsc);
+bool intel_gsc_uc_fw_proxy_init_done(struct intel_gsc_uc *gsc);
 
 #endif
diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp.c b/drivers/gpu/drm/i915/pxp/intel_pxp.c
index 8949d4be7882..b600d68de2a4 100644
--- a/drivers/gpu/drm/i915/pxp/intel_pxp.c
+++ b/drivers/gpu/drm/i915/pxp/intel_pxp.c
@@ -291,6 +291,8 @@ static bool pxp_component_bound(struct intel_pxp *pxp)
 
 static int __pxp_global_teardown_final(struct intel_pxp *pxp)
 {
+	int timeout;
+
 	if (!pxp->arb_is_valid)
 		return 0;
 	/*
@@ -300,7 +302,12 @@ static int __pxp_global_teardown_final(struct intel_pxp *pxp)
 	intel_pxp_mark_termination_in_progress(pxp);
 	intel_pxp_terminate(pxp, false);
 
-	if (!wait_for_completion_timeout(&pxp->termination, msecs_to_jiffies(250)))
+	if (HAS_ENGINE(pxp->ctrl_gt, GSC0))
+		timeout = GSCFW_MAX_ROUND_TRIP_LATENCY_MS;
+	else
+		timeout = 250;
+
+	if (!wait_for_completion_timeout(&pxp->termination, msecs_to_jiffies(timeout)))
 		return -ETIMEDOUT;
 
 	return 0;
@@ -308,6 +315,8 @@ static int __pxp_global_teardown_final(struct intel_pxp *pxp)
 
 static int __pxp_global_teardown_restart(struct intel_pxp *pxp)
 {
+	int timeout;
+
 	if (pxp->arb_is_valid)
 		return 0;
 	/*
@@ -316,7 +325,12 @@ static int __pxp_global_teardown_restart(struct intel_pxp *pxp)
 	 */
 	pxp_queue_termination(pxp);
 
-	if (!wait_for_completion_timeout(&pxp->termination, msecs_to_jiffies(250)))
+	if (HAS_ENGINE(pxp->ctrl_gt, GSC0))
+		timeout = GSCFW_MAX_ROUND_TRIP_LATENCY_MS;
+	else
+		timeout = 250;
+
+	if (!wait_for_completion_timeout(&pxp->termination, msecs_to_jiffies(timeout)))
 		return -ETIMEDOUT;
 
 	return 0;
@@ -354,8 +368,13 @@ int intel_pxp_start(struct intel_pxp *pxp)
 	if (!intel_pxp_is_enabled(pxp))
 		return -ENODEV;
 
-	if (wait_for(pxp_component_bound(pxp), 250))
-		return -ENXIO;
+	if (HAS_ENGINE(pxp->ctrl_gt, GSC0)) {
+		if (wait_for(intel_pxp_gsccs_is_ready_for_sessions(pxp), 250))
+			return -ENXIO;
+	} else {
+		if (wait_for(pxp_component_bound(pxp), 250))
+			return -ENXIO;
+	}
 
 	mutex_lock(&pxp->arb_mutex);
 
diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp_cmd_interface_43.h b/drivers/gpu/drm/i915/pxp/intel_pxp_cmd_interface_43.h
index c65ada99e54f..09777719cd84 100644
--- a/drivers/gpu/drm/i915/pxp/intel_pxp_cmd_interface_43.h
+++ b/drivers/gpu/drm/i915/pxp/intel_pxp_cmd_interface_43.h
@@ -11,6 +11,7 @@
 
 /* PXP-Cmd-Op definitions */
 #define PXP43_CMDID_START_HUC_AUTH 0x0000003A
+#define PXP43_CMDID_INIT_SESSION 0x00000036
 
 /* PXP-Packet sizes for MTL's GSCCS-HECI instruction */
 #define PXP43_MAX_HECI_INOUT_SIZE (SZ_32K)
@@ -26,4 +27,24 @@ struct pxp43_start_huc_auth_out {
 	struct pxp_cmd_header header;
 } __packed;
 
+/* PXP-Input-Packet: Init PXP session */
+struct pxp43_create_arb_in {
+	struct pxp_cmd_header header;
+		/* header.stream_id fields for vesion 4.3 of Init PXP session: */
+		#define PXP43_INIT_SESSION_VALID BIT(0)
+		#define PXP43_INIT_SESSION_APPTYPE BIT(1)
+		#define PXP43_INIT_SESSION_APPID GENMASK(17, 2)
+	u32 protection_mode;
+		#define PXP43_INIT_SESSION_PROTECTION_ARB 0x2
+	u32 sub_session_id;
+	u32 init_flags;
+	u32 rsvd[12];
+} __packed;
+
+/* PXP-Input-Packet: Init PXP session */
+struct pxp43_create_arb_out {
+	struct pxp_cmd_header header;
+	u32 rsvd[8];
+} __packed;
+
 #endif /* __INTEL_PXP_FW_INTERFACE_43_H__ */
diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp_gsccs.c b/drivers/gpu/drm/i915/pxp/intel_pxp_gsccs.c
index 16e3b73d0653..4bc276daca16 100644
--- a/drivers/gpu/drm/i915/pxp/intel_pxp_gsccs.c
+++ b/drivers/gpu/drm/i915/pxp/intel_pxp_gsccs.c
@@ -6,13 +6,46 @@
 #include "gem/i915_gem_internal.h"
 
 #include "gt/intel_context.h"
+#include "gt/uc/intel_gsc_fw.h"
 #include "gt/uc/intel_gsc_uc_heci_cmd_submit.h"
 
 #include "i915_drv.h"
+#include "intel_pxp_cmd_interface_42.h"
 #include "intel_pxp_cmd_interface_43.h"
 #include "intel_pxp_gsccs.h"
 #include "intel_pxp_types.h"
 
+static bool
+is_fw_err_platform_config(u32 type)
+{
+	switch (type) {
+	case PXP_STATUS_ERROR_API_VERSION:
+	case PXP_STATUS_PLATFCONFIG_KF1_NOVERIF:
+	case PXP_STATUS_PLATFCONFIG_KF1_BAD:
+		return true;
+	default:
+		break;
+	}
+	return false;
+}
+
+static const char *
+fw_err_to_string(u32 type)
+{
+	switch (type) {
+	case PXP_STATUS_ERROR_API_VERSION:
+		return "ERR_API_VERSION";
+	case PXP_STATUS_NOT_READY:
+		return "ERR_NOT_READY";
+	case PXP_STATUS_PLATFCONFIG_KF1_NOVERIF:
+	case PXP_STATUS_PLATFCONFIG_KF1_BAD:
+		return "ERR_PLATFORM_CONFIG";
+	default:
+		break;
+	}
+	return NULL;
+}
+
 static int
 gsccs_send_message(struct intel_pxp *pxp,
 		   void *msg_in, size_t msg_in_size,
@@ -152,6 +185,103 @@ gsccs_send_message_retry_complete(struct intel_pxp *pxp,
 	return ret;
 }
 
+bool intel_pxp_gsccs_is_ready_for_sessions(struct intel_pxp *pxp)
+{
+	/*
+	 * GSC-fw loading, HuC-fw loading, HuC-fw authentication and
+	 * GSC-proxy init flow (requiring an mei component driver)
+	 * must all occur first before we can start requesting for PXP
+	 * sessions. Checking for completion on HuC authentication and
+	 * gsc-proxy init flow (the last set of dependencies that
+	 * are out of order) will suffice.
+	 */
+	if (intel_huc_is_authenticated(&pxp->ctrl_gt->uc.huc) &&
+	    intel_gsc_uc_fw_proxy_init_done(&pxp->ctrl_gt->uc.gsc))
+		return true;
+
+	return false;
+}
+
+int intel_pxp_gsccs_create_session(struct intel_pxp *pxp,
+				   int arb_session_id)
+{
+	struct drm_i915_private *i915 = pxp->ctrl_gt->i915;
+	struct pxp43_create_arb_in msg_in = {0};
+	struct pxp43_create_arb_out msg_out = {0};
+	int ret;
+
+	msg_in.header.api_version = PXP_APIVER(4, 3);
+	msg_in.header.command_id = PXP43_CMDID_INIT_SESSION;
+	msg_in.header.stream_id = (FIELD_PREP(PXP43_INIT_SESSION_APPID, arb_session_id) |
+				   FIELD_PREP(PXP43_INIT_SESSION_VALID, 1) |
+				   FIELD_PREP(PXP43_INIT_SESSION_APPTYPE, 0));
+	msg_in.header.buffer_len = sizeof(msg_in) - sizeof(msg_in.header);
+	msg_in.protection_mode = PXP43_INIT_SESSION_PROTECTION_ARB;
+
+	ret = gsccs_send_message_retry_complete(pxp,
+						&msg_in, sizeof(msg_in),
+						&msg_out, sizeof(msg_out), NULL);
+	if (ret) {
+		drm_err(&i915->drm, "Failed to init session %d, ret=[%d]\n", arb_session_id, ret);
+	} else if (msg_out.header.status != 0) {
+		if (is_fw_err_platform_config(msg_out.header.status)) {
+			drm_info_once(&i915->drm,
+				      "PXP init-session-%d failed due to BIOS/SOC:0x%08x:%s\n",
+				      arb_session_id, msg_out.header.status,
+				      fw_err_to_string(msg_out.header.status));
+		} else {
+			drm_dbg(&i915->drm, "PXP init-session-%d failed 0x%08x:%st:\n",
+				arb_session_id, msg_out.header.status,
+				fw_err_to_string(msg_out.header.status));
+			drm_dbg(&i915->drm, "     cmd-detail: ID=[0x%08x],API-Ver-[0x%08x]\n",
+				msg_in.header.command_id, msg_in.header.api_version);
+		}
+	}
+
+	return ret;
+}
+
+void intel_pxp_gsccs_end_arb_fw_session(struct intel_pxp *pxp, u32 session_id)
+{
+	struct drm_i915_private *i915 = pxp->ctrl_gt->i915;
+	struct pxp42_inv_stream_key_in msg_in = {0};
+	struct pxp42_inv_stream_key_out msg_out = {0};
+	int ret = 0;
+
+	/*
+	 * Stream key invalidation reuses the same version 4.2 input/output
+	 * command format but firmware requires 4.3 API interaction
+	 */
+	msg_in.header.api_version = PXP_APIVER(4, 3);
+	msg_in.header.command_id = PXP42_CMDID_INVALIDATE_STREAM_KEY;
+	msg_in.header.buffer_len = sizeof(msg_in) - sizeof(msg_in.header);
+
+	msg_in.header.stream_id = FIELD_PREP(PXP_CMDHDR_EXTDATA_SESSION_VALID, 1);
+	msg_in.header.stream_id |= FIELD_PREP(PXP_CMDHDR_EXTDATA_APP_TYPE, 0);
+	msg_in.header.stream_id |= FIELD_PREP(PXP_CMDHDR_EXTDATA_SESSION_ID, session_id);
+
+	ret = gsccs_send_message_retry_complete(pxp,
+						&msg_in, sizeof(msg_in),
+						&msg_out, sizeof(msg_out), NULL);
+	if (ret) {
+		drm_err(&i915->drm, "Failed to inv-stream-key-%u, ret=[%d]\n",
+			session_id, ret);
+	} else if (msg_out.header.status != 0) {
+		if (is_fw_err_platform_config(msg_out.header.status)) {
+			drm_info_once(&i915->drm,
+				      "PXP inv-stream-key-%u failed due to BIOS/SOC :0x%08x:%s\n",
+				      session_id, msg_out.header.status,
+				      fw_err_to_string(msg_out.header.status));
+		} else {
+			drm_dbg(&i915->drm, "PXP inv-stream-key-%u failed 0x%08x:%s:\n",
+				session_id, msg_out.header.status,
+				fw_err_to_string(msg_out.header.status));
+			drm_dbg(&i915->drm, "     cmd-detail: ID=[0x%08x],API-Ver-[0x%08x]\n",
+				msg_in.header.command_id, msg_in.header.api_version);
+		}
+	}
+}
+
 static void
 gsccs_cleanup_fw_host_session_handle(struct intel_pxp *pxp)
 {
diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp_gsccs.h b/drivers/gpu/drm/i915/pxp/intel_pxp_gsccs.h
index bd1c028bc80f..298ad38e6c7d 100644
--- a/drivers/gpu/drm/i915/pxp/intel_pxp_gsccs.h
+++ b/drivers/gpu/drm/i915/pxp/intel_pxp_gsccs.h
@@ -10,14 +10,22 @@
 
 struct intel_pxp;
 
-#define GSC_REPLY_LATENCY_MS 200
+#define GSC_REPLY_LATENCY_MS 210
+/*
+ * Max FW response time is 200ms, to which we add 10ms to account for overhead
+ * such as request preparation, GuC submission to hw and pipeline completion times.
+ */
 #define GSC_PENDING_RETRY_MAXCOUNT 40
 #define GSC_PENDING_RETRY_PAUSE_MS 50
+#define GSCFW_MAX_ROUND_TRIP_LATENCY_MS (GSC_PENDING_RETRY_MAXCOUNT * GSC_PENDING_RETRY_PAUSE_MS)
 
 #ifdef CONFIG_DRM_I915_PXP
 void intel_pxp_gsccs_fini(struct intel_pxp *pxp);
 int intel_pxp_gsccs_init(struct intel_pxp *pxp);
 
+int intel_pxp_gsccs_create_session(struct intel_pxp *pxp, int arb_session_id);
+void intel_pxp_gsccs_end_arb_fw_session(struct intel_pxp *pxp, u32 arb_session_id);
+
 #else
 static inline void intel_pxp_gsccs_fini(struct intel_pxp *pxp)
 {
@@ -30,4 +38,6 @@ static inline int intel_pxp_gsccs_init(struct intel_pxp *pxp)
 
 #endif
 
+bool intel_pxp_gsccs_is_ready_for_sessions(struct intel_pxp *pxp);
+
 #endif /*__INTEL_PXP_GSCCS_H__ */
diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp_session.c b/drivers/gpu/drm/i915/pxp/intel_pxp_session.c
index 7899079e17b0..e4d8242302c5 100644
--- a/drivers/gpu/drm/i915/pxp/intel_pxp_session.c
+++ b/drivers/gpu/drm/i915/pxp/intel_pxp_session.c
@@ -7,6 +7,7 @@
 
 #include "intel_pxp.h"
 #include "intel_pxp_cmd.h"
+#include "intel_pxp_gsccs.h"
 #include "intel_pxp_session.h"
 #include "intel_pxp_tee.h"
 #include "intel_pxp_types.h"
@@ -62,7 +63,10 @@ static int pxp_create_arb_session(struct intel_pxp *pxp)
 		return -EEXIST;
 	}
 
-	ret = intel_pxp_tee_cmd_create_arb_session(pxp, ARB_SESSION);
+	if (HAS_ENGINE(pxp->ctrl_gt, GSC0))
+		ret = intel_pxp_gsccs_create_session(pxp, ARB_SESSION);
+	else
+		ret = intel_pxp_tee_cmd_create_arb_session(pxp, ARB_SESSION);
 	if (ret) {
 		drm_err(&gt->i915->drm, "tee cmd for arb session creation failed\n");
 		return ret;
@@ -106,7 +110,10 @@ static int pxp_terminate_arb_session_and_global(struct intel_pxp *pxp)
 
 	intel_uncore_write(gt->uncore, KCR_GLOBAL_TERMINATE(pxp->kcr_base), 1);
 
-	intel_pxp_tee_end_arb_fw_session(pxp, ARB_SESSION);
+	if (HAS_ENGINE(gt, GSC0))
+		intel_pxp_gsccs_end_arb_fw_session(pxp, ARB_SESSION);
+	else
+		intel_pxp_tee_end_arb_fw_session(pxp, ARB_SESSION);
 
 	return ret;
 }
diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h
index dba7c5a5b25e..b15dd9cc2ffb 100644
--- a/include/uapi/drm/i915_drm.h
+++ b/include/uapi/drm/i915_drm.h
@@ -2096,6 +2096,21 @@ struct drm_i915_gem_context_param {
  *
  * -ENODEV: feature not available
  * -EPERM: trying to mark a recoverable or not bannable context as protected
+ * -ENXIO: A dependency such as a component driver or firmware is not yet
+ *         loaded so user space may need to attempt again. Depending on the
+ *         device, this error may be reported if protected context creation is
+ *         attempted very early after kernel start because the internal timeout
+ *         waiting for such dependencies is not guaranteed to be larger than
+ *         required (numbers differ depending on system and kernel config):
+ *            - ADL/RPL: dependencies may take up to 3 seconds from kernel start
+ *                       while context creation internal timeout is 250 milisecs
+ *            - MTL: dependencies may take up to 8 seconds from kernel start
+ *                   while context creation internal timeout is 1000 milisecs
+ *         NOTE: such dependencies happen once, so a subsequent call to create a
+ *         protected context after a prior successful call will not experience
+ *         such timeouts and will not return -ENXIO (unless the driver is reloaded,
+ *         or, depending on the device, resumes from a suspended state).
+ * -EIO: The firmware did not succeed in creating the protected context.
  */
 #define I915_CONTEXT_PARAM_PROTECTED_CONTENT    0xd
 /* Must be kept compact -- no holes and well documented */
