drm/xe/pxp: Fail the load if PXP fails to initialize

The PXP implementation mimics the i915 approach of allowing the load
to continue even if PXP init has failed. On Xe however we're taking an
harder stance on boot error and only allowing the load to complete if
everything is working, so update the code to fail if anything goes wrong
during PXP init.

While at it, update the return code in case of PXP not supported to be 0
instead of EOPNOTSUPP, to follow the standard of functions called by
xe_device_probe where every non-zero value means failure.

Suggested-by: Lucas De Marchi <[email protected]>
Signed-off-by: Daniele Ceraolo Spurio <[email protected]>
Cc: Lucas De Marchi <[email protected]>
Cc: John Harrison <[email protected]>
Reviewed-by: Lucas De Marchi <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]

Author: dceraolo

drivers/gpu/drm/xe/xe_device.c

@@ -864,8 +864,8 @@ int xe_device_probe(struct xe_device *xe)
 
 	/* A PXP init failure is not fatal */
 	err = xe_pxp_init(xe);
-	if (err && err != -EOPNOTSUPP)
-		drm_err(&xe->drm, "PXP initialization failed: %pe\n", ERR_PTR(err));
+	if (err)
+		goto err_fini_display;
 
 	err = drm_dev_register(&xe->drm, 0);
 	if (err)

drivers/gpu/drm/xe/xe_pxp.c

@@ -372,8 +372,8 @@ static void pxp_fini(void *arg)
  * are performed asynchronously as part of the GSC init. PXP can only be used
  * after both this function and the async worker have completed.
  *
- * Returns -EOPNOTSUPP if PXP is not supported, 0 if PXP initialization is
- * successful, other errno value if there is an error during the init.
+ * Returns 0 if PXP is not supported or if PXP initialization is successful,
+ * other errno value if there is an error during the init.
  */
 int xe_pxp_init(struct xe_device *xe)
 {
@@ -382,26 +382,28 @@ int xe_pxp_init(struct xe_device *xe)
 	int err;
 
 	if (!xe_pxp_is_supported(xe))
-		return -EOPNOTSUPP;
+		return 0;
 
 	/* we only support PXP on single tile devices with a media GT */
 	if (xe->info.tile_count > 1 || !gt)
-		return -EOPNOTSUPP;
+		return 0;
 
 	/* The GSCCS is required for submissions to the GSC FW */
 	if (!(gt->info.engine_mask & BIT(XE_HW_ENGINE_GSCCS0)))
-		return -EOPNOTSUPP;
+		return 0;
 
 	/* PXP requires both GSC and HuC firmwares to be available */
 	if (!xe_uc_fw_is_loadable(&gt->uc.gsc.fw) ||
 	    !xe_uc_fw_is_loadable(&gt->uc.huc.fw)) {
 		drm_info(&xe->drm, "skipping PXP init due to missing FW dependencies");
-		return -EOPNOTSUPP;
+		return 0;
 	}
 
 	pxp = drmm_kzalloc(&xe->drm, sizeof(struct xe_pxp), GFP_KERNEL);
-	if (!pxp)
-		return -ENOMEM;
+	if (!pxp) {
+		err = -ENOMEM;
+		goto out;
+	}
 
 	INIT_LIST_HEAD(&pxp->queues.list);
 	spin_lock_init(&pxp->queues.lock);
@@ -448,6 +450,8 @@ int xe_pxp_init(struct xe_device *xe)
 	destroy_workqueue(pxp->irq.wq);
 out_free:
 	drmm_kfree(&xe->drm, pxp);
+out:
+	drm_err(&xe->drm, "PXP initialization failed: %pe\n", ERR_PTR(err));
 	return err;
 }