linux-kernel - [PATCH 5.14 136/334] drm: mxsfb: Clear FIFO

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: <20210913131117.962802327@linuxfoundation.org>
Date:   Mon, 13 Sep 2021 15:13:10 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Marek Vasut <marex@...x.de>,
        Daniel Abrecht <public@...ielabrecht.ch>,
        Emil Velikov <emil.l.velikov@...il.com>,
        Laurent Pinchart <laurent.pinchart@...asonboard.com>,
        Lucas Stach <l.stach@...gutronix.de>,
        Stefan Agner <stefan@...er.ch>,
        Jagan Teki <jagan@...rulasolutions.com>,
        Sam Ravnborg <sam@...nborg.org>,
        Sasha Levin <sashal@...nel.org>
Subject: [PATCH 5.14 136/334] drm: mxsfb: Clear FIFO_CLEAR bit

From: Marek Vasut <marex@...x.de>

[ Upstream commit 5e23c98178eb1a2cdb7c4fee9a39baf8cabf282d ]

Make sure the FIFO_CLEAR bit is latched in when configuring the
controller, so that the FIFO is really cleared. And then clear
the FIFO_CLEAR bit, since it is not self-clearing.

Fixes: 45d59d704080 ("drm: Add new driver for MXSFB controller")
Signed-off-by: Marek Vasut <marex@...x.de>
Cc: Daniel Abrecht <public@...ielabrecht.ch>
Cc: Emil Velikov <emil.l.velikov@...il.com>
Cc: Laurent Pinchart <laurent.pinchart@...asonboard.com>
Cc: Lucas Stach <l.stach@...gutronix.de>
Cc: Stefan Agner <stefan@...er.ch>
Reviewed-by: Jagan Teki <jagan@...rulasolutions.com>
Tested-by: Jagan Teki <jagan@...rulasolutions.com> # i.Core MX8MM
Acked-by: Lucas Stach <l.stach@...gutronix.de>
Signed-off-by: Sam Ravnborg <sam@...nborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210620224946.189524-1-marex@denx.de
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 drivers/gpu/drm/mxsfb/mxsfb_kms.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/mxsfb/mxsfb_kms.c b/drivers/gpu/drm/mxsfb/mxsfb_kms.c
index 5bcc06c1ac0b..54f905ac75c0 100644
--- a/drivers/gpu/drm/mxsfb/mxsfb_kms.c
+++ b/drivers/gpu/drm/mxsfb/mxsfb_kms.c
@@ -243,6 +243,9 @@ static void mxsfb_crtc_mode_set_nofb(struct mxsfb_drm_private *mxsfb)
 
 	/* Clear the FIFOs */
 	writel(CTRL1_FIFO_CLEAR, mxsfb->base + LCDC_CTRL1 + REG_SET);
+	readl(mxsfb->base + LCDC_CTRL1);
+	writel(CTRL1_FIFO_CLEAR, mxsfb->base + LCDC_CTRL1 + REG_CLR);
+	readl(mxsfb->base + LCDC_CTRL1);
 
 	if (mxsfb->devdata->has_overlay)
 		writel(0, mxsfb->base + LCDC_AS_CTRL);
-- 
2.30.2