Re: [PATCH v3] mmc: sdhci_am654: Disable HS400 for AM62P SR1.0 and SR1.1

[Judith Mendez <jm@ti.com>]

On 8/19/25 8:21 AM, Adrian Hunter wrote:
> On 18/08/2025 23:38, Andrew Davis wrote:
>> On 8/18/25 3:33 PM, Judith Mendez wrote:
>>> This adds SDHCI_AM654_QUIRK_DISABLE_HS400 quirk which shall be used
>>> to disable HS400 support. AM62P SR1.0 and SR1.1 do not support HS400
>>> due to errata i2458 [0] so disable HS400 for these SoC revisions.
>>>
>>> [0] https://www.ti.com/lit/er/sprz574a/sprz574a.pdf
>>> Signed-off-by: Judith Mendez <jm@ti.com>
>>> ---
>>> This patch was separated from [0] since it will be merged to
>>> different trees anyways.
>>>
>>> Link to v2:
>>> [0] https://lore.kernel.org/linux-mmc/20250807225138.1228333-1-jm@ti.com
>>> ---
>>>    drivers/mmc/host/sdhci_am654.c | 18 ++++++++++++++++++
>>>    1 file changed, 18 insertions(+)
>>>
>>> diff --git a/drivers/mmc/host/sdhci_am654.c b/drivers/mmc/host/sdhci_am654.c
>>> index 8a099508b939..cc8c4145bf2b 100644
>>> --- a/drivers/mmc/host/sdhci_am654.c
>>> +++ b/drivers/mmc/host/sdhci_am654.c
>>> @@ -155,6 +155,7 @@ struct sdhci_am654_data {
>>>      #define SDHCI_AM654_QUIRK_FORCE_CDTEST BIT(0)
>>>    #define SDHCI_AM654_QUIRK_SUPPRESS_V1P8_ENA BIT(1)
>>> +#define SDHCI_AM654_QUIRK_DISABLE_HS400 BIT(2)
>>>    };
>>>      struct window {
>>> @@ -764,6 +765,7 @@ static int sdhci_am654_init(struct sdhci_host *host)
>>>    {
>>>        struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
>>>        struct sdhci_am654_data *sdhci_am654 = sdhci_pltfm_priv(pltfm_host);
>>> +    struct device *dev = mmc_dev(host->mmc);
>>>        u32 ctl_cfg_2 = 0;
>>>        u32 mask;
>>>        u32 val;
>>> @@ -819,6 +821,12 @@ static int sdhci_am654_init(struct sdhci_host *host)
>>>        if (ret)
>>>            goto err_cleanup_host;
>>>    +    if (sdhci_am654->quirks & SDHCI_AM654_QUIRK_DISABLE_HS400 &&
>>> +        host->mmc->caps2 & (MMC_CAP2_HS400 | MMC_CAP2_HS400_ES)) {
>>> +        dev_info(dev, "Disable descoped HS400 mode for this silicon revision\n");
>>
>> Messages to the user do not need to be imperative, maybe:
>>
>> "Disabling HS400 mode not supported on this silicon revision\n"
>>
>> Not a blocker,
>>
>> Reviewed-by: Andrew Davis <afd@ti.com>
> 
> I agree about the message.  Another possibility:
> "HS400 mode is not supported on this silicon revision, disabling it"
> 

Ok, that is no problem, I will fix for v4. Thanks!

~ Judith

> Otherwise:
> 
> Acked-by: Adrian Hunter <adrian.hunter@intel.com>
>