[PATCH v2] serial: prevent armada-xp-98DX SOC uart buffer loss

[PATCH v2] serial: prevent armada-xp-98DX SOC uart buffer loss

[Joshua Scott]

Switch to the "marvell,armada-38x-uart" driver variant to empty
the UART buffer before writing to the UART_LCR register.

Signed-off-by: Joshua Scott <joshua.scott@alliedtelesis.co.nz>
---
Changes in v2:

Andrew Lunn was able to test on a Marvell 370RD reference design, and
the character loss issue did not occur.

The fix has now been changed to only affect the following SOCs:
 * 98DX323x
 * 98DX3333
 * 98DX4251

Cheers,
Joshua Scott
---
 arch/arm/boot/dts/armada-xp-98dx3236.dtsi | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/arch/arm/boot/dts/armada-xp-98dx3236.dtsi b/arch/arm/boot/dts/armada-xp-98dx3236.dtsi
index 59753470cd34..267d0c178e55 100644
--- a/arch/arm/boot/dts/armada-xp-98dx3236.dtsi
+++ b/arch/arm/boot/dts/armada-xp-98dx3236.dtsi
@@ -336,3 +336,11 @@
 	status = "disabled";
 };
 
+&uart0 {
+	compatible = "marvell,armada-38x-uart";
+};
+
+&uart1 {
+	compatible = "marvell,armada-38x-uart";
+};
+
-- 
2.21.0


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Re: [PATCH v2] serial: prevent armada-xp-98DX SOC uart buffer loss

[Gregory CLEMENT]

Hi Joshua,

> Switch to the "marvell,armada-38x-uart" driver variant to empty
> the UART buffer before writing to the UART_LCR register.
>
> Signed-off-by: Joshua Scott <joshua.scott@alliedtelesis.co.nz>

I agree with the content of this patch, so you can add my
Acked-by: Gregory CLEMENT <gregory.clement@bootlin.com>.

However, could you change the title to something like: "ARM: dts:
armada-xp-98dx3236: Switch to armada-38x-uart for serial node"

Indeed for thearm device tree patch we expect that the title start by
"ARM: dts: ". Also could you add back some part of the explanation you
providee in comment with your first patch. I find it very usefull to se
waht happen and who to reproduce the bug.

Finally, as it is a fix, could you add a "Fixes: " tag as well as the
"Cc: stable@kernel.org" tag.

Thanks,

Gregory

> ---
> Changes in v2:
>
> Andrew Lunn was able to test on a Marvell 370RD reference design, and
> the character loss issue did not occur.
>
> The fix has now been changed to only affect the following SOCs:
>  * 98DX323x
>  * 98DX3333
>  * 98DX4251
>
> Cheers,
> Joshua Scott
> ---
>  arch/arm/boot/dts/armada-xp-98dx3236.dtsi | 8 ++++++++
>  1 file changed, 8 insertions(+)
>
> diff --git a/arch/arm/boot/dts/armada-xp-98dx3236.dtsi b/arch/arm/boot/dts/armada-xp-98dx3236.dtsi
> index 59753470cd34..267d0c178e55 100644
> --- a/arch/arm/boot/dts/armada-xp-98dx3236.dtsi
> +++ b/arch/arm/boot/dts/armada-xp-98dx3236.dtsi
> @@ -336,3 +336,11 @@
>  	status = "disabled";
>  };
>  
> +&uart0 {
> +	compatible = "marvell,armada-38x-uart";
> +};
> +
> +&uart1 {
> +	compatible = "marvell,armada-38x-uart";
> +};
> +
> -- 
> 2.21.0
>
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

-- 
Gregory Clement, Bootlin
Embedded Linux and Kernel engineering
http://bootlin.com

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Re: [PATCH v2] serial: prevent armada-xp-98DX SOC uart buffer loss

[Andrew Lunn]

On Tue, Jun 25, 2019 at 11:49:00AM +1200, Joshua Scott wrote:
> Switch to the "marvell,armada-38x-uart" driver variant to empty
> the UART buffer before writing to the UART_LCR register.
> 
> Signed-off-by: Joshua Scott <joshua.scott@alliedtelesis.co.nz>

Hi Joshua

You can add my 

Tested-by: Andrew Lunn <andrew@lunn.ch>

if you want. Not for the usual sense, but i did do some testing :-)

    Andrew

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