linux-kernel - [PATCH v10 13/15] drm/msm/disp/dpu: wait for extra vsync till timing engine status is disabled

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <1671721502-16587-14-git-send-email-quic_vpolimer@quicinc.com>
Date:   Thu, 22 Dec 2022 20:35:00 +0530
From:   Vinod Polimera <quic_vpolimer@...cinc.com>
To:     <dri-devel@...ts.freedesktop.org>, <linux-arm-msm@...r.kernel.org>,
        <freedreno@...ts.freedesktop.org>, <devicetree@...r.kernel.org>
CC:     Vinod Polimera <quic_vpolimer@...cinc.com>,
        <linux-kernel@...r.kernel.org>, <robdclark@...il.com>,
        <dianders@...omium.org>, <swboyd@...omium.org>,
        <quic_kalyant@...cinc.com>, <dmitry.baryshkov@...aro.org>,
        <quic_khsieh@...cinc.com>, <quic_vproddut@...cinc.com>,
        <quic_bjorande@...cinc.com>, <quic_abhinavk@...cinc.com>,
        <quic_sbillaka@...cinc.com>
Subject: [PATCH v10 13/15] drm/msm/disp/dpu: wait for extra vsync till timing engine status is disabled

There can be a race between timing gen disable and vblank irq. The
wait post timing gen disable may return early but intf disable sequence
might not be completed. Ensure that, intf status is disabled before
we retire the function.

Signed-off-by: Vinod Polimera <quic_vpolimer@...cinc.com>
---
 .../gpu/drm/msm/disp/dpu1/dpu_encoder_phys_vid.c    | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_vid.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_vid.c
index 0f71e8f..685cb44 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_vid.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_vid.c
@@ -526,6 +526,7 @@ static void dpu_encoder_phys_vid_disable(struct dpu_encoder_phys *phys_enc)
 {
 	unsigned long lock_flags;
 	int ret;
+	struct intf_status intf_status = {0};
 
 	if (!phys_enc->parent || !phys_enc->parent->dev) {
 		DPU_ERROR("invalid encoder/device\n");
@@ -570,6 +571,26 @@ static void dpu_encoder_phys_vid_disable(struct dpu_encoder_phys *phys_enc)
 		}
 	}
 
+	if (phys_enc->hw_intf && phys_enc->hw_intf->ops.get_status)
+		phys_enc->hw_intf->ops.get_status(phys_enc->hw_intf, &intf_status);
+
+	/*
+	 * Wait for a vsync if timing en status is on after timing engine
+	 * is disabled.
+	 */
+	if (intf_status.is_en && dpu_encoder_phys_vid_is_master(phys_enc)) {
+		spin_lock_irqsave(phys_enc->enc_spinlock, lock_flags);
+		dpu_encoder_phys_inc_pending(phys_enc);
+		spin_unlock_irqrestore(phys_enc->enc_spinlock, lock_flags);
+		ret = dpu_encoder_phys_vid_wait_for_vblank(phys_enc);
+		if (ret) {
+			atomic_set(&phys_enc->pending_kickoff_cnt, 0);
+			DRM_ERROR("wait disable failed: id:%u intf:%d ret:%d\n",
+				  DRMID(phys_enc->parent),
+				  phys_enc->hw_intf->idx - INTF_0, ret);
+		}
+	}
+
 	phys_enc->enable_state = DPU_ENC_DISABLED;
 }
 
-- 
2.7.4