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From: Paul Mackerras <paulus@samba.org>
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Message-ID: <15553.12447.849592.261245@argo.ozlabs.ibm.com>
Date: Sat, 20 Apr 2002 19:10:55 +1000 (EST)
To: "David S. Miller" <davem@redhat.com>
Cc: peterson@austin.ibm.com, anton@au.ibm.com, mj@suse.cz,
        linux-kernel@vger.kernel.org
Subject: Re: PowerPC Linux and PCI
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David S. Miller writes:

>    From: James L Peterson <peterson@austin.ibm.com>
>    Date: Fri, 19 Apr 2002 16:37:03 -0500
> 
>    if (pci_read_config_dword(temp, PCI_VENDOR_ID, &l))
>      return NULL;
>         ....
>      memcpy(dev, temp, sizeof(*dev));
>     dev->vendor = l & 0xffff;
>     dev->device = (l >> 16) & 0xffff;
>    
>    It seems to me this is incorrect for a big-endian machine
>    (like PowerPC).  If we read the two 16-bit parts out of the
>    first 32-bit part, we will end up with:
> 
> pci_read_config_dword should do the byte swapping on &l for
> the caller, fix your pci_{read,write}_config_*() arch implementation.

It does, that's why it all works. :)  James Peterson seems to have
missed this fact, hence his confusion.

Paul.
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