Date:   Thu, 9 Feb 2023 01:10:21 +0100
From:   Pali =?utf-8?B?Um9ow6Fy?= <pali@kernel.org>
To:     Michael Ellerman <mpe@ellerman.id.au>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Rob Herring <robh+dt@kernel.org>,
        Sebastian Reichel <sre@kernel.org>
Cc:     linux-pm@vger.kernel.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org
Subject: Re: [PATCH v4 3/3] powerpc: dts: turris1x.dts: Set lower priority
 for CPLD syscon-reboot
Message-ID: <20230209001021.oitnv6x7ilwvy4it@pali>
References: <20220820102925.29476-1-pali@kernel.org>
 <20221226114513.4569-1-pali@kernel.org>
 <20221226114513.4569-3-pali@kernel.org>
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On Monday 26 December 2022 12:45:13 Pali Rohár wrote:
> Due to CPLD firmware bugs, set CPLD syscon-reboot priority level to 64
> (between rstcr and watchdog) to ensure that rstcr's global-utilities reset
> method which is preferred stay as default one, and to ensure that CPLD
> syscon-reboot is more preferred than watchdog reset method.
> 
> Fixes: 0531a4abd1c6 ("powerpc: dts: turris1x.dts: Add CPLD reboot node")
> Signed-off-by: Pali Rohár <pali@kernel.org>

May I ask who can take this 3/3 patch? powersupply or powerpc tree?

> ---
>  arch/powerpc/boot/dts/turris1x.dts | 23 +++++++++++++++++++++++
>  1 file changed, 23 insertions(+)
> 
> diff --git a/arch/powerpc/boot/dts/turris1x.dts b/arch/powerpc/boot/dts/turris1x.dts
> index e9cda34a140e..c9b619f6ed5c 100644
> --- a/arch/powerpc/boot/dts/turris1x.dts
> +++ b/arch/powerpc/boot/dts/turris1x.dts
> @@ -367,11 +367,34 @@
>  			};
>  
>  			reboot@d {
> +				/*
> +				 * CPLD firmware which manages system reset and
> +				 * watchdog registers has bugs. It does not
> +				 * autoclear system reset register after change
> +				 * and watchdog ignores reset line on immediate
> +				 * succeeding reset cycle triggered by watchdog.
> +				 * These bugs have to be workarounded in U-Boot
> +				 * bootloader. So use system reset via syscon as
> +				 * a last resort because older U-Boot versions
> +				 * do not have workaround for watchdog.
> +				 *
> +				 * Reset method via rstcr's global-utilities
> +				 * (the preferred one) has priority level 128,
> +				 * watchdog has priority level 0 and default
> +				 * syscon-reboot priority level is 192.
> +				 *
> +				 * So define syscon-reboot with custom priority
> +				 * level 64 (between rstcr and watchdog) because
> +				 * rstcr should stay as default preferred reset
> +				 * method and reset via watchdog is more broken
> +				 * than system reset via syscon.
> +				 */
>  				compatible = "syscon-reboot";
>  				reg = <0x0d 0x01>;
>  				offset = <0x0d>;
>  				mask = <0x01>;
>  				value = <0x01>;
> +				priority = <64>;
>  			};
>  
>  			led-controller@13 {
> -- 
> 2.20.1
>