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SubjectRe: [PATCH 4/4] mmc: mmci: add hs200 support for stm32 sdmmc
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On 12/16/21 10:44, Yann Gautier wrote:
> On 12/16/21 10:14 AM, Marek Vasut wrote:
>> On 12/15/21 15:17, Yann Gautier wrote:
>>> Use feedback clock for HS200 mode, as for SDR104.
>>> The HS200 mode can be enabled through DT by using mmc-hs200-1_8v.
>>> It is possible to use it on STM32MP13, but not STM32MP15 platforms.
>>
>> HS200 is possible even on the MP15, it just doesn't yield any
>> (performance) benefits due to the slower bus clock (125 MHz or so?),
>> so it isn't worth enabling it on MP15. It is nice to see MP13 can do
>> better.
>
> Hi Marek,
>
> There is a limitation on MP15, please see errata sheet [1], chapter 2.3.19.
> HS200 (and SDR104) shouldn't be enabled on MP15.
>
> Best regards,
> Yann
>
> [1] https://www.st.com/resource/en/errata_sheet/dm00516256.pdf

Oh, I see, so I was lucky to even ever get it working at all.

Thanks for the info.

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