Re: [PATCH 5/9] dt-bindings: mmc: mmci: add delay block base register for sdmmc

[Ludovic BARRE <ludovic.barre@st.com>]

Le 1/16/20 à 3:33 PM, Rob Herring a écrit :
> On Thu, Jan 16, 2020 at 3:21 AM Ludovic BARRE <ludovic.barre@st.com> wrote:
>>
>> Hi Rob
>>
>> Le 1/15/20 à 3:56 PM, Rob Herring a écrit :
>>> On Fri, Jan 10, 2020 at 02:48:19PM +0100, Ludovic Barre wrote:
>>>> To support the sdr104 mode, the sdmmc variant has a
>>>> hardware delay block to manage the clock phase when sampling
>>>> data received by the card.
>>>>
>>>> This patch adds a second base register (optional) for
>>>> sdmmc delay block.
>>>>
>>>> Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
>>>> ---
>>>>    Documentation/devicetree/bindings/mmc/mmci.txt | 2 ++
>>>>    1 file changed, 2 insertions(+)
>>>>
>>>> diff --git a/Documentation/devicetree/bindings/mmc/mmci.txt b/Documentation/devicetree/bindings/mmc/mmci.txt
>>>> index 6d3c626e017d..4ec921e4bf34 100644
>>>> --- a/Documentation/devicetree/bindings/mmc/mmci.txt
>>>> +++ b/Documentation/devicetree/bindings/mmc/mmci.txt
>>>> @@ -28,6 +28,8 @@ specific for ux500 variant:
>>>>    - st,sig-pin-fbclk       : feedback clock signal pin used.
>>>>
>>>>    specific for sdmmc variant:
>>>> +- reg                        : a second base register may be defined if a delay
>>>> +                           block is present and used for tuning.
>>>
>>> Which compatibles have a 2nd reg entry?
>>
>> In fact, mmci driver is ARM Amba driver (arm,primecell) and has only one
>> compatible "arm,pl18x".
>> The variants are identified by primecell-periphid property
>> (discovered at runtime with HW block register or defined by
>> device tree property "arm,primecell-periphid").
>>
>> The defaults "arm,pl18x" variants have only one base register,
>> but the SDMMC need a second base register for these
>> delay block registers.
>>
>> example of sdmmc node:
>>          sdmmc1: sdmmc@58005000 {
>>                  compatible = "arm,pl18x", "arm,primecell";
>>                  arm,primecell-periphid = <0x00253180>;
>>                  reg = <0x58005000 0x1000>, <0x58006000 0x1000>;
>>          };
>>
>> what do you advise?
> 
> I missed that this is a primecell block. Just give some indication
> which variants have this 2nd range.

Thanks Rob.
I will add primecell id(s) concerned by this 2nd range.

> 0
> Rob
>