drm/i915/dg2: setup HuC loading via GSC

The GSC will perform both the load and the authentication, so we just
need to check the auth bit after the GSC has replied.
Since we require the PXP module to load the HuC, the earliest we can
trigger the load is during the pxp_bind operation.

Note that GSC-loaded HuC survives GT reset, so we need to just mark it
as ready when we re-init the GT HW.

V2: move setting of HuC fw error state to the failure path of the HuC
auth function, so it covers both the legacy and new auth flows
V4:
1. Fix typo in the commit message
2. style fix in intel_huc_wait_for_auth_complete()
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: Vitaly Lubart <vitaly.lubart@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Reviewed-by: Alan Previn <alan.previn.teres.alexis@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220928004145.745803-11-daniele.ceraolospurio@intel.com

drivers/gpu/drm/i915/gt/uc/intel_huc.c

@@ -125,6 +125,28 @@ void intel_huc_fini(struct intel_huc *huc)
 	intel_uc_fw_fini(&huc->fw);
 }
 
+int intel_huc_wait_for_auth_complete(struct intel_huc *huc)
+{
+	struct intel_gt *gt = huc_to_gt(huc);
+	int ret;
+
+	ret = __intel_wait_for_register(gt->uncore,
+					huc->status.reg,
+					huc->status.mask,
+					huc->status.value,
+					2, 50, NULL);
+
+	if (ret) {
+		drm_err(&gt->i915->drm, "HuC: Firmware not verified %d\n", ret);
+		intel_uc_fw_change_status(&huc->fw, INTEL_UC_FIRMWARE_LOAD_FAIL);
+		return ret;
+	}
+
+	intel_uc_fw_change_status(&huc->fw, INTEL_UC_FIRMWARE_RUNNING);
+	drm_info(&gt->i915->drm, "HuC authenticated\n");
+	return 0;
+}
+
 /**
  * intel_huc_auth() - Authenticate HuC uCode
  * @huc: intel_huc structure
@@ -161,27 +183,18 @@ int intel_huc_auth(struct intel_huc *huc)
 	}
 
 	/* Check authentication status, it should be done by now */
-	ret = __intel_wait_for_register(gt->uncore,
-					huc->status.reg,
-					huc->status.mask,
-					huc->status.value,
-					2, 50, NULL);
-	if (ret) {
-		DRM_ERROR("HuC: Firmware not verified %d\n", ret);
+	ret = intel_huc_wait_for_auth_complete(huc);
+	if (ret)
 		goto fail;
-	}
 
-	intel_uc_fw_change_status(&huc->fw, INTEL_UC_FIRMWARE_RUNNING);
-	drm_info(&gt->i915->drm, "HuC authenticated\n");
 	return 0;
 
 fail:
 	i915_probe_error(gt->i915, "HuC: Authentication failed %d\n", ret);
-	intel_uc_fw_change_status(&huc->fw, INTEL_UC_FIRMWARE_LOAD_FAIL);
 	return ret;
 }
 
-static bool huc_is_authenticated(struct intel_huc *huc)
+bool intel_huc_is_authenticated(struct intel_huc *huc)
 {
 	struct intel_gt *gt = huc_to_gt(huc);
 	intel_wakeref_t wakeref;
@@ -223,7 +236,7 @@ int intel_huc_check_status(struct intel_huc *huc)
 		break;
 	}
 
-	return huc_is_authenticated(huc);
+	return intel_huc_is_authenticated(huc);
 }
 
 void intel_huc_update_auth_status(struct intel_huc *huc)
@@ -231,7 +244,7 @@ void intel_huc_update_auth_status(struct intel_huc *huc)
 	if (!intel_uc_fw_is_loadable(&huc->fw))
 		return;
 
-	if (huc_is_authenticated(huc))
+	if (intel_huc_is_authenticated(huc))
 		intel_uc_fw_change_status(&huc->fw,
 					  INTEL_UC_FIRMWARE_RUNNING);
 }

drivers/gpu/drm/i915/gt/uc/intel_huc.h

@@ -26,8 +26,10 @@ void intel_huc_init_early(struct intel_huc *huc);
 int intel_huc_init(struct intel_huc *huc);
 void intel_huc_fini(struct intel_huc *huc);
 int intel_huc_auth(struct intel_huc *huc);
+int intel_huc_wait_for_auth_complete(struct intel_huc *huc);
 int intel_huc_check_status(struct intel_huc *huc);
 void intel_huc_update_auth_status(struct intel_huc *huc);
+bool intel_huc_is_authenticated(struct intel_huc *huc);
 
 static inline int intel_huc_sanitize(struct intel_huc *huc)
 {

drivers/gpu/drm/i915/gt/uc/intel_huc_fw.c

@@ -3,9 +3,43 @@
  * Copyright © 2014-2019 Intel Corporation
  */
 
+#include "gt/intel_gsc.h"
 #include "gt/intel_gt.h"
+#include "intel_huc.h"
 #include "intel_huc_fw.h"
 #include "i915_drv.h"
+#include "pxp/intel_pxp_huc.h"
+
+int intel_huc_fw_load_and_auth_via_gsc(struct intel_huc *huc)
+{
+	int ret;
+
+	if (!intel_huc_is_loaded_by_gsc(huc))
+		return -ENODEV;
+
+	if (!intel_uc_fw_is_loadable(&huc->fw))
+		return -ENOEXEC;
+
+	/*
+	 * If we abort a suspend, HuC might still be loaded when the mei
+	 * component gets re-bound and this function called again. If so, just
+	 * mark the HuC as loaded.
+	 */
+	if (intel_huc_is_authenticated(huc)) {
+		intel_uc_fw_change_status(&huc->fw, INTEL_UC_FIRMWARE_RUNNING);
+		return 0;
+	}
+
+	GEM_WARN_ON(intel_uc_fw_is_loaded(&huc->fw));
+
+	ret = intel_pxp_huc_load_and_auth(&huc_to_gt(huc)->pxp);
+	if (ret)
+		return ret;
+
+	intel_uc_fw_change_status(&huc->fw, INTEL_UC_FIRMWARE_TRANSFERRED);
+
+	return intel_huc_wait_for_auth_complete(huc);
+}
 
 /**
  * intel_huc_fw_upload() - load HuC uCode to device via DMA transfer

drivers/gpu/drm/i915/gt/uc/intel_huc_fw.h

@@ -8,6 +8,7 @@
 
 struct intel_huc;
 
+int intel_huc_fw_load_and_auth_via_gsc(struct intel_huc *huc);
 int intel_huc_fw_upload(struct intel_huc *huc);
 
 #endif

drivers/gpu/drm/i915/pxp/intel_pxp_tee.c

@@ -15,6 +15,7 @@
 #include "intel_pxp_session.h"
 #include "intel_pxp_tee.h"
 #include "intel_pxp_tee_interface.h"
+#include "intel_pxp_huc.h"
 
 static inline struct intel_pxp *i915_dev_to_pxp(struct device *i915_kdev)
 {
@@ -127,13 +128,24 @@ static int i915_pxp_tee_component_bind(struct device *i915_kdev,
 {
 	struct drm_i915_private *i915 = kdev_to_i915(i915_kdev);
 	struct intel_pxp *pxp = i915_dev_to_pxp(i915_kdev);
+	struct intel_uc *uc = &pxp_to_gt(pxp)->uc;
 	intel_wakeref_t wakeref;
+	int ret = 0;
 
 	mutex_lock(&pxp->tee_mutex);
 	pxp->pxp_component = data;
 	pxp->pxp_component->tee_dev = tee_kdev;
 	mutex_unlock(&pxp->tee_mutex);
 
+	if (intel_uc_uses_huc(uc) && intel_huc_is_loaded_by_gsc(&uc->huc)) {
+		with_intel_runtime_pm(&i915->runtime_pm, wakeref) {
+			/* load huc via pxp */
+			ret = intel_huc_fw_load_and_auth_via_gsc(&uc->huc);
+			if (ret < 0)
+				drm_err(&i915->drm, "failed to load huc via gsc %d\n", ret);
+		}
+	}
+
 	/* if we are suspended, the HW will be re-initialized on resume */
 	wakeref = intel_runtime_pm_get_if_in_use(&i915->runtime_pm);
 	if (!wakeref)
@@ -145,7 +157,7 @@ static int i915_pxp_tee_component_bind(struct device *i915_kdev,
 
 	intel_runtime_pm_put(&i915->runtime_pm, wakeref);
 
-	return 0;
+	return ret;
 }
 
 static void i915_pxp_tee_component_unbind(struct device *i915_kdev,