From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 213F7CCFA10 for ; Tue, 4 Nov 2025 08:36:54 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id A934A10E56E; Tue, 4 Nov 2025 08:36:53 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=lankhorst.se header.i=@lankhorst.se header.b="As93AkEN"; dkim-atps=neutral Received: from lankhorst.se (lankhorst.se [141.105.120.124]) by gabe.freedesktop.org (Postfix) with ESMTPS id 8056310E56B; Tue, 4 Nov 2025 08:36:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=lankhorst.se; s=default; t=1762245409; bh=Fd7xqMKtI1czeZVZmJUm2zI3Khx3lzpsyMWufRJ+Cw8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=As93AkENGMkbwPoa0FSt5rwfNKyLYT7u89ildkhoN38RkFkgrONr+85xGiXk9TeV5 7XkXMLRfpkiTixfke/eGkDqpF6g1SjxI+Y/0pEMdHvSbkrad2ltmJi48S6Rp1PzFfS 0YzKovgRersgq5aO71TAcXssivkaRAj7VUZyG+ztohv8bv3JFkm5JqQlcr/B6o3CyU g67Cv3w0vOnMtBc/uG/ZVjvYwfGxMSLxhu9liC6IhIx1/WFFzhgJxd4wtpq6Xje/ax fk1mGFiNCU08enwVjiO236gPxxtWc3fxIEp7Z85cf4AdkWA3q6JBR6dmCQn7OeGdXu JqKXKx2EwYU6Q== From: Maarten Lankhorst To: intel-gfx@lists.freedesktop.org, intel-xe@lists.freedesktop.org Cc: linux-rt-devel@lists.linux.dev, Maarten Lankhorst , Mario Kleiner , Mike Galbraith , Thomas Gleixner , Sebastian Andrzej Siewior , Clark Williams , Steven Rostedt Subject: [PATCH v2 6/7] drm/i915/display: Enable interrupts earlier on PREEMPT_RT Date: Tue, 4 Nov 2025 09:36:30 +0100 Message-ID: <20251104083634.670753-7-dev@lankhorst.se> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20251104083634.670753-1-dev@lankhorst.se> References: <20251104083634.670753-1-dev@lankhorst.se> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-BeenThere: intel-xe@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel Xe graphics driver List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-xe-bounces@lists.freedesktop.org Sender: "Intel-xe" The last part of the vblank evasion is about updating bookkeeping, not programming hardware registers. The interrupts cannot stay disabled here on PREEMPT_RT since the spinlocks get converted to mutexes. Signed-off-by: Maarten Lankhorst --- drivers/gpu/drm/i915/display/intel_crtc.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/gpu/drm/i915/display/intel_crtc.c b/drivers/gpu/drm/i915/display/intel_crtc.c index 9d2a23c96c61b..b87f6b4a4f3d7 100644 --- a/drivers/gpu/drm/i915/display/intel_crtc.c +++ b/drivers/gpu/drm/i915/display/intel_crtc.c @@ -688,6 +688,14 @@ void intel_pipe_update_end(struct intel_atomic_state *state, intel_crtc_has_type(new_crtc_state, INTEL_OUTPUT_DSI)) icl_dsi_frame_update(new_crtc_state); +#if IS_ENABLED(CONFIG_PREEMPT_RT) + /* + * Timing sensitive register writing completed, non-deterministic + * locking from here on out. + */ + local_irq_enable(); +#endif + /* We're still in the vblank-evade critical section, this can't race. * Would be slightly nice to just grab the vblank count and arm the * event outside of the critical section - the spinlock might spin for a @@ -735,7 +743,9 @@ void intel_pipe_update_end(struct intel_atomic_state *state, if (!state->base.legacy_cursor_update) intel_vrr_send_push(NULL, new_crtc_state); +#if !IS_ENABLED(CONFIG_PREEMPT_RT) local_irq_enable(); +#endif if (intel_vgpu_active(dev_priv)) goto out; -- 2.51.0