Re: [PATCH] PCI: enable extended tags support for PCIe endpoints

From: Sinan Kaya
Date: Wed Jan 25 2017 - 13:33:49 EST

On 1/25/2017 12:49 PM, Sinan Kaya wrote:
> Hi Bjorn,
> On 11/11/2016 3:58 PM, Bjorn Helgaas wrote:
>>> Is there any other feedback?
>> If this were completely safe to enable for every device that supported
>> it, why would there be an enable bit in Device Control?
>> I don't know anything about extended tags, but it worries me a little
>> when there's a "go-fast" switch and no explanation about when and why
>> we might need to go slow.

I tried to answer your question in the new commit message. All PCIe completers
are required to support 8 bit tags.

Generation of 8 bit tags is optional. That's why, there is a supported and an
enable/disable bit.

> I have v2 posted. Do you feel like applying to linux-next to get some testing
> exposure or do you want to tie it to some DMI so that we enable it only on
> recent HW?
> Sinan

Sinan Kaya
Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.