drm/xe/pxp: do not queue unneeded terminations from debugfs

The PXP terminate debugfs currently unconditionally simulates a
termination, no matter what the HW status is. This is unneeded if PXP is
not in use and can cause errors if the HW init hasn't completed yet.
To solve these issues, we can simply limit the terminations to the cases
where PXP is fully initialized and in use.

v2: s/pxp_status/ready/ to avoid confusion with pxp->status (John)

Fixes: 385a801 ("drm/xe/pxp: Add PXP debugfs support")
Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/4749
Signed-off-by: Daniele Ceraolo Spurio <[email protected]>
Cc: John Harrison <[email protected]>
Reviewed-by: John Harrison <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

Author: dceraolo

drivers/gpu/drm/xe/xe_pxp_debugfs.c

@@ -66,9 +66,18 @@ static int pxp_terminate(struct seq_file *m, void *data)
 {
 	struct xe_pxp *pxp = node_to_pxp(m->private);
 	struct drm_printer p = drm_seq_file_printer(m);
+	int ready = xe_pxp_get_readiness_status(pxp);
 
-	if (!xe_pxp_is_enabled(pxp))
-		return -ENODEV;
+	if (ready < 0)
+		return ready; /* disabled or error occurred */
+	else if (!ready)
+		return -EBUSY; /* init still in progress */
+
+	/* no need for a termination if PXP is not active */
+	if (pxp->status != XE_PXP_ACTIVE) {
+		drm_printf(&p, "PXP not active\n");
+		return 0;
+	}
 
 	/* simulate a termination interrupt */
 	spin_lock_irq(&pxp->xe->irq.lock);