Message-ID: <05ab7b52-190e-048f-3803-7bed51e2b09c@denx.de>
Date:   Thu, 16 Dec 2021 10:13:27 +0100
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Subject: Re: [PATCH 3/4] mmc: mmci: stm32: clear DLYB_CR after sending tuning
 command
Content-Language: en-US
To:     Yann Gautier <yann.gautier@foss.st.com>, linux-mmc@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        linux-stm32@st-md-mailman.stormreply.com,
        linux-arm-kernel@lists.infradead.org
References: <20211215141727.4901-1-yann.gautier@foss.st.com>
 <20211215141727.4901-4-yann.gautier@foss.st.com>
Cc:     Ulf Hansson <ulf.hansson@linaro.org>,
        Russell King <linux@armlinux.org.uk>,
        Maxime Coquelin <mcoquelin.stm32@gmail.com>,
        Alexandre Torgue <alexandre.torgue@foss.st.com>,
        Philipp Zabel <p.zabel@pengutronix.de>,
        Linus Walleij <linus.walleij@linaro.org>,
        Vladimir Zapolskiy <vz@mleia.com>,
        u.kleine-koenig@pengutronix.de,
        Christophe Kerello <christophe.kerello@foss.st.com>,
        Ludovic Barre <ludovic.barre@foss.st.com>
From:   Marek Vasut <marex@denx.de>
In-Reply-To: <20211215141727.4901-4-yann.gautier@foss.st.com>
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Precedence: bulk

On 12/15/21 15:17, Yann Gautier wrote:
> During test campaign, and especially after several unbind/bind sequences,
> it has been seen that the SD-card on SDMMC1 thread could freeze.
> The freeze always appear on a CMD23 following a CMD19.
> Checking SDMMC internal registers shows that the tuning command (CMD19)
> has failed.
> The freeze is then due to the delay block involved in the tuning sequence.
> To correct this, clear the delay block register DLYB_CR register after
> the tuning commands.
> 
> Signed-off-by: Christophe Kerello <christophe.kerello@foss.st.com>
> Signed-off-by: Yann Gautier <yann.gautier@foss.st.com>
> ---
>   drivers/mmc/host/mmci_stm32_sdmmc.c | 2 ++
>   1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/mmc/host/mmci_stm32_sdmmc.c b/drivers/mmc/host/mmci_stm32_sdmmc.c
> index fdaa11f92fe6..a75d3dd34d18 100644
> --- a/drivers/mmc/host/mmci_stm32_sdmmc.c
> +++ b/drivers/mmc/host/mmci_stm32_sdmmc.c
> @@ -441,6 +441,8 @@ static int sdmmc_dlyb_phase_tuning(struct mmci_host *host, u32 opcode)
>   		return -EINVAL;
>   	}
>   
> +	writel_relaxed(0, dlyb->base + DLYB_CR);
> +
>   	phase = end_of_len - max_len / 2;
>   	sdmmc_dlyb_set_cfgr(dlyb, dlyb->unit, phase, false);

Shouldn't this have a Fixes: tag and be CC stable ?
This seems like a bugfix, no ?