Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Message-ID: <8271d551-4034-71fe-5be4-e08e28b6dd6b@linux.intel.com>
Date:   Mon, 26 Sep 2022 10:58:18 +0300
MIME-Version: 1.0
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101
 Firefox/91.0 Thunderbird/91.11.0
Content-Language: en-US
To:     liulongfang <liulongfang@huawei.com>, gregkh@linuxfoundation.org,
        mathias.nyman@intel.com
Cc:     linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org,
        yisen.zhuang@huawei.com
References: <20220915011134.58400-1-liulongfang@huawei.com>
 <6b5a45f1-caf3-4259-77da-e36788f5b8a9@linux.intel.com>
 <2648444c-2f2a-4d9b-8545-6677663adcf0@huawei.com>
From:   Mathias Nyman <mathias.nyman@linux.intel.com>
Subject: Re: [PATCH] xhci: print warning when HCE was set
In-Reply-To: <2648444c-2f2a-4d9b-8545-6677663adcf0@huawei.com>
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 7bit
Precedence: bulk

On 24.9.2022 5.35, liulongfang wrote:
> On 2022/9/22 21:01, Mathias Nyman Wrote:
>> Hi
>>
>> On 15.9.2022 4.11, Longfang Liu wrote:
>>> When HCE(Host Controller Error) is set, it means that the xhci hardware
>>> controller has an error at this time, but the current xhci driver
>>> software does not log this event.
>>>
>>> By adding an HCE event detection in the xhci interrupt processing
>>> interface, a warning log is output to the system, which is convenient
>>> for system device status tracking.
>>>
>>
>> xHC should cease all activity when it sets HCE, and is probably not
>> generating interrupts anymore.
>>
>> Would probably be more useful to check for HCE at timeouts than in the
>> interrupt handler.
>>
> 
> Which function of the driver code is this timeout in?

xhci_handle_command_timeout() will usually trigger at some point,

> 
>> If this is something seen on actual hardware then it makes sense to add it.
>>
> 
> This HCE error is sure to report an interrupt on the chip we are using.

Ok, then makes sense to add this patch.

Thanks
-Mathias