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Date: Wed, 13 Jul 2011 10:41:16 +1000
From: Tony Breeds <tony@bakeyournoodle.com>
To: Ayman El-Khashab <ayman@elkhashab.com>
Subject: Re: [PATCH] 4xx: Add check_link to struct ppc4xx_pciex_hwops
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On Tue, Jul 12, 2011 at 05:13:38PM -0500, Ayman El-Khashab wrote:

> Ok, so let me ask the following ... will it cause trouble if
> I swap the sequence of the calls to the following in xxx_port_init
> 
> ppc4xx_pciex_port_init_mapping(...)
> 
> and
> 
> if (ppc4xx_pciex_hwops->check_link)...
> 
> The reason is that at least on the 460SX, the link check is
> done via registers in the config space.  But the init_mapping is 
> needed to setup some of the DCRs to make the config space work.  
> In my check_link, i map the config space do the link checks
> and then unmap since a superset of the space could be mapped
> later.

This is also what I do.  IIRC ppc4xx_pciex_port_init_mapping() required
things that are setup between the 2 calls.

The double Mapping is fugly but I think it should be safe.

Yours Tony