Re: [PATCH v3] xhci: workaround CSS timeout on AMD SNPS 3.0 xHC

[Mathias Nyman <mathias.nyman@intel.com>]

On 27.11.2018 09:44, Kai Heng Feng wrote:
> 
> 
>> On Nov 24, 2018, at 00:24, Singh, Sandeep <sandeep.singh@amd.com> wrote:
>>
>> From: Sandeep Singh <sandeep.singh@amd.com>
>>
>> Occasionally AMD SNPS 3.0 xHC does not respond to
>> CSS when set, also it does not flag anything on SRE and HCE
>> to point the internal xHC errors on USBSTS register. This stalls
>> the entire system wide suspend and there is no point in stalling
>> just because of xHC CSS is not responding.
>>
>> To work around this problem, if the xHC does not flag
>> anything on SRE and HCE, we can skip the CSS
>> timeout and allow the system to continue the suspend. Once the
>> system resume happens we can internally reset the controller
>> using XHCI_RESET_ON_RESUME quirk
>>
>> Signed-off-by: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
>> Signed-off-by: Sandeep Singh <Sandeep.Singh@amd.com>
>> cc: Nehal Shah <Nehal-bakulchandra.Shah@amd.com>
> 
> Tested-by: Kai-Heng Feng <kai.heng.feng@canonical.com>

Thanks, applying

-Mathias