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Date:   Thu, 16 Aug 2018 16:26:40 -0700
From:   "Luck, Tony" <tony.luck@intel.com>
To:     Arnd Bergmann <arnd@arndb.de>
Cc:     Bjorn Helgaas <bhelgaas@google.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        jchandra@broadcom.com, Sinan Kaya <okaya@codeaurora.org>,
        Tomasz Nowicki <tn@semihalf.com>,
        Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>,
        Boris Brezillon <boris.brezillon@bootlin.com>,
        Miquel Raynal <miquel.raynal@bootlin.com>
Subject: Re: how to fix acpi_pci_root_remap_iospace?
Message-ID: <20180816232639.GA25889@agluck-desk>
References: <20180816204506.GA21144@agluck-desk>
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On Thu, Aug 16, 2018 at 11:10:33PM +0200, Arnd Bergmann wrote:
> Another way would be to add
> 
>  #include <asm-generic/io.h>
> +#undef PCI_IOBASE
> 
> in your asm/io.h. This is about as ugly as the your version, but
> it would be local to ia64 ;-)

Third way ...


Is "0" actually the right value for PCI_IOBASE for some platform?

#ifndef PCI_IOBASE
#define PCI_IOBASE ((void __iomem *)0)
#endif

Or is this just here to make sure that:

static inline u8 inb(unsigned long addr)
{
        u8 val;

        __io_pbr();
        val = __raw_readb(PCI_IOBASE + addr);
        __io_par();
        return val;
}

etc. Do not throw errors?

Should we really just enclose all of inb, inw, inl, ...
inside of:

#ifdef PCI_IOBASE

... all those static functions that use PCI_IOBASE ...

#endif


-Tony