Re: [PATCH 0/3] mmc: add support for sdhci 4.0

[Chunyan Zhang]

Hi Adrian,

On 20 March 2018 at 17:18, Adrian Hunter <adrian.hunter@xxxxxxxxx> wrote:
> On 20/03/18 10:36, Chunyan Zhang wrote:
>>>From the SD host controller version 4.0 on, SDHCI implementation either
>> is version 3 compatible or version 4 mode. This patch-set covers those
>> changes which are common for SDHCI 4.0 version, regardless of whether
>> they are used with SD or eMMC storage devices.
>
> Why use v4 mode?
>
> What driver is using v4 mode?  Can you also post those changes?

I believe there must be some out-of-tree driver using v4 mode, at
least Spreadtrum's sd host controller is, as I know, and they're
planning on upstreaming that driver.

Those changes which this patch-set covers are just in the subject of
each patch in this series :)

>
> Are you planning on adding UHS-II support also?

Yes, that's my preliminary plan.

BTW, this patchset should have prefix "RFC", I just forgot to add that.

Thanks for your comments,
Chunyan

>
>>
>> Chunyan Zhang (3):
>>   mmc: sdhci: add sd host v4 mode
>>   mmc: sdhci: made changes for System Address register of SDMA
>>   mmc: sdhci: add ADMA2 64-bit addressing support for V4 mode
>>
>>  drivers/mmc/host/sdhci.c | 66 +++++++++++++++++++++++++++++++++++++-----------
>>  drivers/mmc/host/sdhci.h | 29 +++++++++++++++++----
>>  2 files changed, 75 insertions(+), 20 deletions(-)
>>
>