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Subject: Re: [PATCH 1/4] PCI: dwc: Add new feature to skip core initialization
To:     Christoph Hellwig <hch@infradead.org>
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References: <20191113090851.26345-1-vidyas@nvidia.com>
 <20191113090851.26345-2-vidyas@nvidia.com>
 <20191127094844.GA21122@infradead.org>
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From:   Vidya Sagar <vidyas@nvidia.com>
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Date:   Fri, 29 Nov 2019 20:10:10 +0530
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On 11/27/2019 3:18 PM, Christoph Hellwig wrote:
> On Wed, Nov 13, 2019 at 02:38:48PM +0530, Vidya Sagar wrote:
>> +	if (ep->ops->get_features) {
>> +		epc_features = ep->ops->get_features(ep);
>> +		if (epc_features->skip_core_init)
>> +			return 0;
>>   	}
>>   
>> +	return dw_pcie_ep_init_complete(ep);
> 
> This calling convention is strange.  Just split the early part of
> dw_pcie_ep_init into an dw_pcie_ep_early and either add a tiny
> wrapper like:
> 
> int dw_pcie_ep_init(struct dw_pcie_ep *ep)
> {
> 	int error;
> 
> 	error = dw_pcie_ep_init_early(ep);
> 	if (error)
> 		return error;
> 	return dw_pcie_ep_init_late(ep);
> }
> 
> or just open code that in the few callers.  That keeps the calling
> conventions much simpler and avoids relying on a callback and flag.
I'm not sure if I got this right. I think in any case, code that is going to be
part of dw_pcie_ep_init_late() needs to depend on callback and flag right?
I mean, unless it is confirmed (by calling the get_features() callback and
checking whether or not the core is available for programming) dw_pcie_ep_init_late()
can't be called right?
Please let me know if I'm missing something here.

- Vidya Sagar
>