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Date: Wed, 29 Jul 2015 12:53:04 -0700
Message-ID: <CAE9FiQXC5P3qZC7CS0UBq4=Uz9mcvgguP0EgV7G0x-PnRZn9-w@mail.gmail.com>
Subject: Re: [RFC PATCH v2] PCI: Only enable IO window if supported
From: Yinghai Lu <yinghai@kernel.org>
To: Guenter Roeck <linux@roeck-us.net>
Cc: Bjorn Helgaas <bhelgaas@google.com>,
	"linux-pci@vger.kernel.org" <linux-pci@vger.kernel.org>,
	Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
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On Wed, Jul 29, 2015 at 12:46 PM, Guenter Roeck <linux@roeck-us.net> wrote:
> On 07/29/2015 12:30 PM, Yinghai Lu wrote:
>
>>
>> so PCI_BUS_FLAGS_SUPPORTS_IO will never get set.
>>
>
> excellent catch. Unfortunately, I don't know how to make it
> work with the reversed flag. The idea here was that the flag
> propagates from parent to child. This makes sense for an
> "it doesn't work" flag to be inherited from the child,
> but not for an "it works" flag.
>

also would be better if we can add has_ioport in hostbridge instead.
like has_mem64 in https://patchwork.ozlabs.org/patch/500926/
and use

to_pci_host_bridge(bus->bridge)->has_ioport

to replace pci_root_has_io_resource()

Thanks

Yinghai