Re: [RFC PATCH v3 2/5] Documentation: synopsys-dw-mshc: add bindings for idmac and edmac

[Shawn Lin <shawn.lin@rock-chips.com>]

在 2015/8/5 16:27, Krzysztof Kozlowski 写道:
> On 05.08.2015 17:17, Shawn Lin wrote:
>> synopsys-dw-mshc supports three types of transfer mode. We add bindings
>> and description for how to use them at runtime. Without idmac and edmac
>> property, pio is the default transfer mode. Make sure that Idmac and emdac
>> should not be used simultaneously.
>>
>> Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
>> ---
>>
>> Changes in v3: None
>> Changes in v2: None
>>
>>   .../devicetree/bindings/mmc/synopsys-dw-mshc.txt   | 41 ++++++++++++++++++++++
>>   1 file changed, 41 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/mmc/synopsys-dw-mshc.txt b/Documentation/devicetree/bindings/mmc/synopsys-dw-mshc.txt
>> index 346c609..30369cb 100644
>> --- a/Documentation/devicetree/bindings/mmc/synopsys-dw-mshc.txt
>> +++ b/Documentation/devicetree/bindings/mmc/synopsys-dw-mshc.txt
>> @@ -75,6 +75,25 @@ Optional properties:
>>   * vmmc-supply: The phandle to the regulator to use for vmmc.  If this is
>>     specified we'll defer probe until we can find this regulator.
>>   
>> +* supports-idmac: Enables support for internal DMAC block within the Synopsys
>> +  Designware Mobile Storage IP block. If supports-idmac property is present, then
>> +  we MUST NOT add supports-edmac property since we'd assume that dw-mshc IP is
>> +  integrated with only one type of dma master.
>> +
>> +* supports-edmac: Enables support for external DMAC block outside the Synopsys
>> +  Designware Mobile Storage IP block. If supports-edmac property is present, then
>> +  we MUST NOT add supports-idmac property since we'd assume that dw-mshc IP is
>> +  integrated with only one type of dma master.
>> +
>> +  (Without "supports-idmac" and "supports-edmac", use PIO as default transfer mode)
> Aren't you breaking here backward compatibility with existing DTB?
>
> Best regards,
> Krzysztof

  Thanks, Krzysztof.
  I guess you mean that I should keep existing DTB w/o these two 
properties work fine using idmac?
>> +
>> +* dmas: List of DMA specifiers with the controller specific format as described
>> +  in the generic DMA client binding. This property should be combined with
>> +  supports-edmac. Refer to dma.txt for details.
>> +
>> +* dma-names: DMA request names. Must be "rx-tx". And This property should be
>> +  combined with supports-edmac. Refer to dma.txt for details.
>> +
>>   Aliases:
>>   
>>   - All the MSHC controller nodes should be represented in the aliases node using
>> @@ -95,6 +114,8 @@ board specific portions as listed below.
>>   		#size-cells = <0>;
>>   	};
>>   
>> +[board specific internal DMA resources]
>> +
>>   	dwmmc0@12200000 {
>>   		clock-frequency = <400000000>;
>>   		clock-freq-min-max = <400000 200000000>;
>> @@ -106,4 +127,24 @@ board specific portions as listed below.
>>   		bus-width = <8>;
>>   		cap-mmc-highspeed;
>>   		cap-sd-highspeed;
>> +		supports-idmac;
>>   	};
>> +
>> +[board specific generic DMA request binding]
>> +
>> +	dwmmc0@12200000 {
>> +		clock-frequency = <400000000>;
>> +		clock-freq-min-max = <400000 200000000>;
>> +		num-slots = <1>;
>> +		broken-cd;
>> +		fifo-depth = <0x80>;
>> +		card-detect-delay = <200>;
>> +		vmmc-supply = <&buck8>;
>> +		bus-width = <8>;
>> +		cap-mmc-highspeed;
>> +		cap-sd-highspeed;
>> +		supports-edmac;
>> +		dmas = <&pdma 12>;
>> +		dma-names = "rx-tx";
>> +	};
>> +
>>
>
>
>


-- 
Shawn Lin