From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sinan Kaya <okaya@codeaurora.org>
Subject: Re: [PATCH V4 11/26] iommu/amd: deprecate pci_get_bus_and_slot()
Date: Thu, 4 Jan 2018 11:32:26 -0500
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To: Gary R Hook <gary.hook@amd.com>, linux-pci@vger.kernel.org, timur@codeaurora.org
Cc: linux-arm-msm@vger.kernel.org, "open list:AMD IOMMU (AMD-VI)" <iommu@lists.linux-foundation.org>, linux-arm-kernel@lists.infradead.org, open list <linux-kernel@vger.kernel.org>

On 1/4/2018 11:28 AM, Gary R Hook wrote:
> On 01/04/2018 06:25 AM, Sinan Kaya wrote:
>> On 12/19/2017 12:37 AM, Sinan Kaya wrote:
>>> pci_get_bus_and_slot() is restrictive such that it assumes domain=0 as
>>> where a PCI device is present. This restricts the device drivers to be
>>> reused for other domain numbers.
>>>
>>> Getting ready to remove pci_get_bus_and_slot() function in favor of
>>> pci_get_domain_bus_and_slot().
>>>
>>> Hard-code the domain number as 0 for the AMD IOMMU driver.
> 
> <snip>
> 
>>
>> Any comments from the IOMMU people?
>>
> 
> pci_get_bus_and_slot() appears to (now) be a convenience function that wraps pci_get_domain_bus_and_slot() while using a 0 for the domain value. Exactly what you are doing here, albeit in a more overt way.
> 
> How is this patch advantageous? Seems to me that if other domains need to be enabled, that driver could be changed if and when that requirement arises.
> 
> But perhaps I'm missing a nuance here.
> 
> 

The benefit of the change was discussed here:

https://lkml.org/lkml/2017/12/19/349

I hope it helps.


-- 
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.