Re: [PATCH v9 02/12] PCI: OF: Parse and map the IRQ when adding the PCI device.

From: Wei Yang <weiyang@linux.vnet.ibm.com>
To: Catalin Marinas <catalin.marinas@arm.com>
Cc: Liviu Dudau <Liviu.Dudau@arm.com>,
	Wei Yang <weiyang@linux.vnet.ibm.com>,
	Bjorn Helgaas <bhelgaas@google.com>,
	Will Deacon <Will.Deacon@arm.com>,
	Benjamin Herrenschmidt <benh@kernel.crashing.org>,
	Arnd Bergmann <arnd@arndb.de>,
	Russell King <linux@arm.linux.org.uk>,
	Tanmay Inamdar <tinamdar@apm.com>,
	Grant Likely <grant.likely@secretlab.ca>,
	Sinan Kaya <okaya@codeaurora.org>,
	Jingoo Han <jg1.han@samsung.com>,
	Kukjin Kim <kgene.kim@samsung.com>,
	Suravee Suthikulanit <suravee.suthikulpanit@amd.com>,
	linux-pci <linux-pci@vger.kernel.org>,
	linux-arch <linux-arch@vger.kernel.org>,
	LKML <linux-kernel@vger.kernel.org>,
	Device Tree ML <devicetree@vger.kernel.org>,
	LAKML <linux-arm-kernel@lists.infradead.org>
Subject: Re: [PATCH v9 02/12] PCI: OF: Parse and map the IRQ when adding the PCI device.
Date: Tue, 19 Aug 2014 09:44:01 +0800	[thread overview]
Message-ID: <20140819014401.GB9558@richard> (raw)
In-Reply-To: <20140818142550.GN20043@localhost>

On Mon, Aug 18, 2014 at 03:25:50PM +0100, Catalin Marinas wrote:
>...
>> Well, it will become necessary as old code gets dismantled and converted towards
>> this patchset. To give you an example that I'm familiar with, for arch/arm the
>> host bridge drivers have moved into drivers/pci/host, but they still depend/use
>> the bios32 infrastructure that takes care of setting up the irq. When they switch
>> to my version they would have to go and debug the "irq not being assigned" issue
>> and it is quite likely that some of the people doing the conversion will complain
>> about my code rather than understanding the issue. What I'm trying to do is to
>> make switching to my patchset as painless as possible, with a cleanup to remove
>> redundant operations coming after the switchover.
>
>While the goal is fine, until we see a common pattern for what needs to
>go into pcibios_add_device() I think we should have an arm64-specific
>implementation (and probably an arm32 specific one as well). I can see
>powerpc uses it for setting the DMA ops. Would we have a similar need on
>arm64 to choose between coherent and non-coherent dma_ops?

Liviu,

I have the same feeling with Catalin. An arm64-specific implementation of
pcibios_add_device() would be better.

No more other concerns from my side.

>
>Also at some point we'll get ACPI support, so I'm not sure what we do
>with assigning the dev->irq here but definitely of_* functions won't
>work.
>
>-- 
>Catalin

-- 
Richard Yang
Help you, Help me