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From: Sinan Kaya <okaya@codeaurora.org>
Newsgroups: linux.kernel
Subject: Re: [PATCH V3] PCI/ASPM: reconfigure ASPM following hotplug for  POLICY_DEFAULT
Date: Mon, 13 Mar 2017 22:10:04 +0100
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Hi Bjorn,

On 3/9/2017 5:27 PM, Bjorn Helgaas wrote:
> This is an aspect of the ASPM design that I don't like:
> 
>   - pcie_aspm_init_link_state() is called on a *bridge* after we've
>     enumerated any devices below the bridge, and we allocate the
>     link_state.
> 
>   - pcie_aspm_exit_link_state() is called on an *endpoint*, and if
>     we're removing the last endpoint below a bridge, we release the
>     *parent's* link_state.

I just posted V4 a minute ago. I divided ASPM init into two so that the
ASPM registers are captured in device_add path. 

There is a section of the ASPM init code that needs to walk all the devices
under the bridge. 

This section of the code is not working in device_add path as the link list
for child devices has not been set up yet. 

Unless you tell me there is a better way to handle this, I don't see how
we can remove the call from scan_slot. 

After further review, I think I can split PATCH V4 3/3 into two. Before
diving into too much clean up, I wanted to get some feedback as it is
obvious from the messed up cover letter.

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.