diff mbox series

arm64: dts: imx8mp: Disable UART4 by default on Data Modul i.MX8M Plus eDM SBC

Message ID 20231220000345.42593-1-marex@denx.de
State Accepted
Commit f03869698bc3bd6d9d2d9f216b20da08a8c2508a
Headers show
Series arm64: dts: imx8mp: Disable UART4 by default on Data Modul i.MX8M Plus eDM SBC | expand

Commit Message

Marek Vasut Dec. 20, 2023, 12:02 a.m. UTC
UART4 is used as CM7 coprocessor debug UART and may not be accessible from
Linux in case it is protected by RDC. The RDC protection is set up by the
platform firmware. UART4 is not used on this platform by Linux. Disable
UART4 by default to prevent boot hangs, which occur when the RDC protection
is in place.

Fixes: 562d222f23f0 ("arm64: dts: imx8mp: Add support for Data Modul i.MX8M Plus eDM SBC")
Signed-off-by: Marek Vasut <marex@denx.de>
---
Cc: Conor Dooley <conor+dt@kernel.org>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>
Cc: NXP Linux Team <linux-imx@nxp.com>
Cc: Pengutronix Kernel Team <kernel@pengutronix.de>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: devicetree@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
---
 arch/arm64/boot/dts/freescale/imx8mp-data-modul-edm-sbc.dts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Fabio Estevam Dec. 29, 2023, 11:01 p.m. UTC | #1
On Tue, Dec 19, 2023 at 9:04 PM Marek Vasut <marex@denx.de> wrote:
>
> UART4 is used as CM7 coprocessor debug UART and may not be accessible from
> Linux in case it is protected by RDC. The RDC protection is set up by the
> platform firmware. UART4 is not used on this platform by Linux. Disable
> UART4 by default to prevent boot hangs, which occur when the RDC protection
> is in place.
>
> Fixes: 562d222f23f0 ("arm64: dts: imx8mp: Add support for Data Modul i.MX8M Plus eDM SBC")
> Signed-off-by: Marek Vasut <marex@denx.de>

Reviewed-by: Fabio Estevam <festevam@gmail.com>
diff mbox series

Patch

diff --git a/arch/arm64/boot/dts/freescale/imx8mp-data-modul-edm-sbc.dts b/arch/arm64/boot/dts/freescale/imx8mp-data-modul-edm-sbc.dts
index 34e9aecc403bd..88e1b76d7d75f 100644
--- a/arch/arm64/boot/dts/freescale/imx8mp-data-modul-edm-sbc.dts
+++ b/arch/arm64/boot/dts/freescale/imx8mp-data-modul-edm-sbc.dts
@@ -491,7 +491,7 @@  &uart3 {	/* A53 Debug */
 &uart4 {
 	pinctrl-names = "default";
 	pinctrl-0 = <&pinctrl_uart4>;
-	status = "okay";
+	status = "disabled";
 };
 
 &usb3_phy0 {