[PATCH v3] PCI: Xilinx-NWL-PCIe: Added support for Xilinx NWL PCIe Host Controller

Marc Zyngier marc.zyngier at arm.com
Fri Oct 9 02:02:39 PDT 2015

On 09/10/15 09:51, Bharat Kumar Gogada wrote:
>> On 09/10/15 06:11, Bharat Kumar Gogada wrote:
>>>>>> +struct nwl_msi {                  /* struct nwl_msi - MSI information
>>>> */
>>>>>> +  struct msi_controller chip;     /* chip: MSI controller */
>>>>>> We're moving away from msi_controller altogether, as the kernel now
>>>>>> has all the necessary infrastructure to do this properly.
>>>>> Our current GIC version does not have separate msi controller (we
>>>>> are not using GICv2m or GICv3), so is it necessary to have separate
>>>>> msi controller node ? Please give me clarity on this.
>>>> This has nothing to do with the version of the GIC you are using
>>>> (XGene doesn't have GICv2m or v3 either). This is about reducing code
>>>> duplication and having something that we can maintain. See also
>>>> https://lkml.org/lkml/2015/9/20/193 for yet another example.
>>>> I still plan to kill msi_controller, and I'd like to avoid more
>>>> dependencies with it. MSI domains are the way to do it.
>>> Sorry previously I haven't configured my email client properly so resending.
>> Thanks for doing so, much appreciated.
>>> Since we don't have separate MSI controller, and our PCIe controller
>>> is handling MSI, is it necessary to create a separate MSI controller
>>> node because we don't have any 'reg' space.
>> No, your PCI controller can perfectly be part of the PCIe node.
> You meant 'msi-controller' property to be part of PCIe node?

Yeah, sorry. Too early, not enough coffee.

>>> Please let me know whether we require a separate msi file as suggested
>>> in your previous comments to separate MSI controller and PCIE
>>> controller in two files, if we don't have separate node. If we do not
>>> need a separate node do we need to embed MSI controller child node  in
>>> PCIe controller node itself, and what properties does this child node
>>> will require other than 'interrupts'.
>> If you want to keep them in the same file, please at least have two separate
>> patches. These are two different functions, and they should be reviewed
>> separately.
> What I meant is if we don't have separate msi node do we need separate file? 

That's up to you. Nodes and source code files don't have to match at all.

> If you meant msi controller to be part of same node then we will use single file and will
> try to have two separate patches.

That's fine by me.


Jazz is not dead. It just smells funny...

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