Re: [PATCH 1/6] dt-bindings: usb: dwc3: add property to disable xhci 64bit support

[Florian Fainelli <f.fainelli@gmail.com>]

On 6/9/2020 7:47 PM, Peter Chen wrote:
> On 20-06-09 19:12:40, Li Jun wrote:
>> Add a property "snps,xhci-dis-64bit-support-quirk" to disable xhci 64bit
>> address support, this is due to SoC integration can't support it but
>> the AC64 bit (bit 0) of HCCPARAMS1 is set to be 1.
>>
>> Signed-off-by: Li Jun <jun.li@nxp.com>
>> ---
>>  Documentation/devicetree/bindings/usb/dwc3.txt | 3 +++
>>  1 file changed, 3 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/usb/dwc3.txt b/Documentation/devicetree/bindings/usb/dwc3.txt
>> index d03edf9..d16cba7 100644
>> --- a/Documentation/devicetree/bindings/usb/dwc3.txt
>> +++ b/Documentation/devicetree/bindings/usb/dwc3.txt
>> @@ -109,6 +109,9 @@ Optional properties:
>>  			When just one value, which means INCRX burst mode enabled. When
>>  			more than one value, which means undefined length INCR burst type
>>  			enabled. The values can be 1, 4, 8, 16, 32, 64, 128 and 256.
>> + - snps,xhci-dis-64bit-support-quirk: set if the AC64 bit (bit 0) of HCCPARAMS1 is set
>> +			to be 1, but the controller actually can't handle 64-bit address
>> +			due to SoC integration.
>>  
>>   - in addition all properties from usb-xhci.txt from the current directory are
>>     supported as well
> 
> Why not adding it at usb-xhci.txt directly? It is more like general
> property, I see Renesas rcar platforms also have this quirk.
> 

Or rather define a compatible string for the specific SoC integration
here and based upon that compatibility string set the xhci->quirks to
have XHCI_NO_64BIT_SUPPORT set.
-- 
Florian