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Date:   Fri, 26 Jan 2018 08:53:43 +0100
From:   Christoph Hellwig <hch@lst.de>
To:     Florian Fainelli <f.fainelli@gmail.com>
Cc:     Christoph Hellwig <hch@lst.de>, Rob Herring <robh+dt@kernel.org>,
        Jim Quinlan <jim2101024@gmail.com>,
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        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will.deacon@arm.com>,
        Brian Norris <computersforpeace@gmail.com>,
        Russell King <rmk+kernel@armlinux.org.uk>,
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        Mark Rutland <mark.rutland@arm.com>,
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        <devicetree@vger.kernel.org>,
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        <linux-arm-kernel@lists.infradead.org>
Subject: Re: [PATCH v4 4/8] PCI: brcmstb: Add dma-range mapping for inbound
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On Wed, Jan 24, 2018 at 12:04:58PM -0800, Florian Fainelli wrote:
> This looks nicer than the current shape, but this still requires to
> register a PCI fixup to override phys_to_dma() and dma_to_phys(), and it
> would appear that you have dodged my question about how this is supposed
> to fit with an entirely modular PCIe root complex driver? Are you
> suggesting that we split the module into a built-in part and a modular part?

I don't think entirely modular PCI root bridges should be a focal point
for the design.  If we happen to support them by other design choices:
fine, but they should not be a priority.

That being said if we have core dma mapping or PCIe code that has
a list of offsets and the root complex only populates them it should
work just fine.