Re: [PATCH 1/3] doc: dt: bindings: usb: dwc3: Update entries for disabling SS instances in park mode

From: Neil Armstrong
Date: Tue Dec 10 2019 - 03:55:58 EST


Hi,

On 12/11/2019 21:03, Thinh Nguyen wrote:
> Hi,
>
> Jun Li wrote:
>> This bug exists on all current versions per information I got from Synopsys.
>> + Thinh Nguyen <thinhn@xxxxxxxxxxxx>.
>>
>> Li Jun
>
> The GUCTL1.PARKMODE_DISABLE_SS is only available in dwc_usb3 controller
> running in host mode. This should not be set for other IPs.
>
> This can be disabled by default based on IP, but I recommend to have a
> property to enable this feature for devices that need this.

Thanks, so this patchset is the right way to solve this.

Felipe, would it be possible to have it merged for next release ?
Should I resend it ?

Thanks,
Neil

>
>
>>
>> Neil Armstrong <narmstrong@xxxxxxxxxxxx> ä2019å11æ12æåä äå5:00åéï
>>> Hi Li,
>>>
>>> On 11/11/2019 02:58, Jun Li wrote:
>>>> Hi Neil
>>>>
>>>> As I got the information from Synopsys, this bug exists on current IP versions,
>>>> and per my tests with external USB3 hub + 2 Super speed udisks on data
>>>> read by dd, I can reproduce this issue with different kernel versions, also I
>>>> didn't see obvious performance drop by dd tests after disable park mode for
>>>> super speed, so should we just disable it by default so no need a quirk?
>>> I don't have any opinion on this, I think the USB & DWC3 maintainers should decide
>>> how to handle this.
>>>
>>> Did Synopsys specified a range of affected IP version ?
>>>
>>> Neil
>>>
>>>> Li Jun
>>>>
>>>> Tim <elatllat@xxxxxxxxx> ä2019å11æ11æåä äå8:42åéï
>>>>> Thanks for working on this Neil,
>>>>> Is there something that needs doing for this patch to make it into 5.3 or 5.4?
>>>>> As previously mentioned the patch set fixes the issue on affected hardware;
>>>>> https://urldefense.proofpoint.com/v2/url?u=https-3A__patchwork.kernel.org_patch_11164515_&d=DwIFaQ&c=DPL6_X_6JkXFx7AXWqB0tg&r=u9FYoxKtyhjrGFcyixFYqTjw1ZX0VsG2d8FCmzkTY-w&m=BCfRHM9e86039Su0-QvK_yUjNnYrnl_BcvxTtViypT8&s=aV5u7uxNX6oTLB3_-qNuzrNvyiqx_rPC6P9TMqG-LNE&e=
>>>>>
>>>>>
>>>>>
>>>>> On Wed, Oct 23, 2019 at 4:11 PM Rob Herring <robh@xxxxxxxxxx> wrote:
>>>>>> On Mon, Oct 14, 2019 at 04:17:16PM +0200, Neil Armstrong wrote:
>>>>>>> This patch updates the documentation with the information related
>>>>>>> to the quirks that needs to be added for disabling all SuperSpeed XHCi
>>>>>>> instances in park mode.
>>>>>>>
>>>>>>> CC: Dongjin Kim <tobetter@xxxxxxxxx>
>>>>>>> Cc: Jianxin Pan <jianxin.pan@xxxxxxxxxxx>
>>>>>>> Reported-by: Tim <elatllat@xxxxxxxxx>
>>>>>>> Signed-off-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
>>>>>>> ---
>>>>>>> Documentation/devicetree/bindings/usb/dwc3.txt | 2 ++
>>>>>>> 1 file changed, 2 insertions(+)
>>>>>> Sigh, what's one more to the never ending list of quirks...
>>>>>>
>>>>>> Acked-by: Rob Herring <robh@xxxxxxxxxx>
>
> BR,
> Thinh
>