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Message-ID: <f59e7f17-b978-4ff3-86d4-a77191ca66ac@ti.com>
Date: Fri, 12 Apr 2024 10:22:46 +0530
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Subject: Re: [PATCH 7/7] arm64: dts: ti: k3-j784s4-evm: Remove HS400 mode
 support for eMMC
To: Judith Mendez <jm@ti.com>, Rob Herring <robh@kernel.org>,
        Krzysztof
 Kozlowski <krzysztof.kozlowski+dt@linaro.org>
CC: Nishanth Menon <nm@ti.com>, Vignesh Raghavendra <vigneshr@ti.com>,
        Tero
 Kristo <kristo@kernel.org>, Conor Dooley <conor+dt@kernel.org>,
        <linux-arm-kernel@lists.infradead.org>, <devicetree@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, Bhavya Kapoor <b-kapoor@ti.com>,
        Dasnavis
 Sabiya <sabiya.d@ti.com>
References: <20240411225257.383889-1-jm@ti.com>
 <20240411225257.383889-8-jm@ti.com>
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From: "Kumar, Udit" <u-kumar1@ti.com>
In-Reply-To: <20240411225257.383889-8-jm@ti.com>
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Hi Judith

On 4/12/2024 4:22 AM, Judith Mendez wrote:
> From: Udit Kumar <u-kumar1@ti.com>
>
> The eMMC fails to enumerate intermittently on HS400 mode. Also
> observing multiple CQE recovery warnings.
>
> Update the sdhci0 node to disable HS400.
>
> Cc: Vignesh Raghavendra <vigneshr@ti.com>
> Cc: Bhavya Kapoor <b-kapoor@ti.com>
> Cc: Siddharth Vadapalli <s-vadapalli@ti.com>
> Signed-off-by: Udit Kumar <u-kumar1@ti.com>
> Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
> [Judith: Reword commit]
> Signed-off-by: Judith Mendez <jm@ti.com>
> ---
>   arch/arm64/boot/dts/ti/k3-j784s4-evm.dts | 1 +
>   1 file changed, 1 insertion(+)
>
> diff --git a/arch/arm64/boot/dts/ti/k3-j784s4-evm.dts b/arch/arm64/boot/dts/ti/k3-j784s4-evm.dts
> index 81fd7afac8c57..04a241a91e6b8 100644
> --- a/arch/arm64/boot/dts/ti/k3-j784s4-evm.dts
> +++ b/arch/arm64/boot/dts/ti/k3-j784s4-evm.dts
> @@ -791,6 +791,7 @@ &main_sdhci0 {
>   	non-removable;
>   	ti,driver-strength-ohm = <50>;
>   	disable-wp;
> +	no-mmc-hs400;

This is just WA to get rid of CQE errors. I prefer to hold this patch 
under debug from hardware side is not complete.

Moreover, CQE errors are seen with 32GB variant not with 16GB, So we can 
not blame controller for this


>   };
>   
>   &main_sdhci1 {