drm/amd/display: Improvements in secure display

[Why]
- Need error message when failing to allocating secure_display_ctx.
- Need to check if secure display context in psp is initialized or not
before using it.

[How]
- Add error message when memory allocation fail.
- Add check before accessing psp secure display context.
Acked-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Signed-off-by: Alan Liu <HaoPing.Liu@amd.com>
Reviewed-by: Wayne Lin <Wayne.Lin@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c

@@ -1643,6 +1643,9 @@ static int amdgpu_dm_init(struct amdgpu_device *adev)
 #endif
 #if defined(CONFIG_DRM_AMD_SECURE_DISPLAY)
 	adev->dm.secure_display_ctxs = amdgpu_dm_crtc_secure_display_create_contexts(adev);
+	if (!adev->dm.secure_display_ctxs) {
+		DRM_ERROR("amdgpu: failed to initialize secure_display_ctxs.\n");
+	}
 #endif
 	if (dc_is_dmub_outbox_supported(adev->dm.dc)) {
 		init_completion(&adev->dm.dmub_aux_transfer_done);

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crc.c

@@ -117,6 +117,12 @@ static void amdgpu_dm_crtc_notify_ta_to_read(struct work_struct *work)
 	}
 
 	psp = &drm_to_adev(crtc->dev)->psp;
+
+	if (!psp->securedisplay_context.context.initialized) {
+		DRM_DEBUG_DRIVER("Secure Display fails to notify PSP TA\n");
+		return;
+	}
+
 	stream = to_amdgpu_crtc(crtc)->dm_irq_params.stream;
 	phy_inst = stream->link->link_enc_hw_inst;